Microchip implant (animal)
Implant used in animals
A microchip implant is an identifying integrated circuit placed under the skin of an animal. The chip, about the size of a large grain of rice, uses passive radio-frequency identification (RFID) technology, and is also known as a PIT (passive integrated transponder) tag. Standard pet microchips are typically 11–13 mm long (approximately <templatestyles src="Fraction/styles.css" />1⁄2 inch) and 2 mm in diameter.
Externally attached microchips such as RFID ear tags are commonly used to identify farm and ranch animals, with the exception of horses. Some external microchips can be read with the same scanner used with implanted chips.
Animal shelters, animal control officers and veterinarians routinely look for microchips to return lost pets quickly to their owners, avoiding expenses for housing, food, medical care, outplacing and euthanasia. Many shelters place chips in all outplaced animals.
Microchips are also used by kennels, breeders, brokers, trainers, registries, rescue groups, humane societies, clinics, farms, stables, animal clubs and associations, researchers, and pet stores.
Usage.
Since their first use in the mid-1980s, microchips have allowed innovative investigations into numerous biological traits of animals. The tiny, coded markers implanted into individual animals allow assessment of growth rates, movement patterns, and survival patterns for many species in a manner more reliable than traditional approaches of externally marking animals for identification. Microchips have also been used to confirm the identity of pets and protected species that have been illegally removed from the wild.
Microchips can be implanted by a veterinarian or at a shelter. After checking that the animal does not already have a chip, the vet or technician injects the chip with a syringe and records the chip's unique ID. No anesthetic is required, as it is a simple procedure and causes little discomfort; the pain is minimal and short-lived. In dogs and cats, chips are usually inserted below the skin at the back of the neck between the shoulder blades on the dorsal midline. According to one reference, continental European pets get the implant in the left side of the neck. The chip can often be felt under the skin. Thin layers of connective tissue form around the implant and hold it in place.
Horses are microchipped on the left side of the neck, halfway between the poll and withers and approximately one inch below the midline of the mane, into the nuchal ligament.
Birds are implanted in their breast muscles. Proper restraint is necessary so the operation requires either two people (an avian veterinarian and a veterinary technician) or general anesthesia. Studies on horses show swelling and increased sensitivity take approximately three days to resolve. Humans report swelling and bruising at the time of implant, two to four weeks for scar tissue to form and itching and pinching sensations for up to two years. A test scan ensures correct operation.
Some shelters and vets designate themselves as the primary contact to remain informed about possible problems with the animals they place. The form is sent to a registry, who may be the chip manufacturer, distributor or an independent entity such as a pet recovery service. Some countries have a single official national database. For a fee, the registry typically provides 24-hour, toll-free telephone service for the life of the pet. Some veterinarians leave registration to the owner, usually done online, but a chip without current contact information is essentially useless.
The owner receives a registration certificate with the chip ID and recovery service contact information. The information can also be imprinted on a collar tag worn by the animal. Like an automobile title, the certificate serves as proof of ownership and is transferred with the animal when it is sold or traded; an animal without a certificate could be stolen. There are some privacy concerns regarding the use of microchips.
Authorities and shelters examine strays for chips, providing one of the aforementioned recovery services with the ID number, description and location so that the recovery service may notify the owner, a contact, or veterinarians in the area. If the pet is wearing the collar tag, the finder does not need a chip reader to contact the registry because a rescuer can simply read the ID number and phone number (or website) to provide to the registry. An owner can also report a missing pet to the recovery service, as vets look for chips in new animals and check with the recovery service to see if it has been reported lost or stolen.
Many veterinarians scan an animal's chip on every visit to verify correct operation. Some use the chip ID as their database index and print it on receipts, test results, vaccination certifications and other records.
Some veterinary tests and procedures require positive identification of the animal, and a microchip may be acceptable for this purpose as an alternative to a tattoo.
Some pet doors can be programmed to be activated by the microchips of specific animals, allowing only certain animals to use the door.
Advantages of data collection.
Pets.
There are multiple reasons for the use of the microchips on pets as a documentation device, which are also advantages of microchips regarding information collection. The three major reasons for microchip implantation are , recording, domestication and showing proof of ownership. For example, with a feline microchip, delocalization shows that a registered cat is one that society is aware of and the cat has a position in the social order of animals. Recording shows that the microchip helps authorized people review and monitor cats in a certain region by referring to the database; thus the registry and the implanted microchips transform cats into social objects.
Livestock.
Due to the advantages of microchips, there are many concrete applications of RFID in the agri-food sector covering the majority of usual foods, such as all kinds of meats as well as various vegetables, fruits. The feature of RFID, namely its traceability, makes it possible for the increased security and confidence of customers. As one of the most popular livestock around the world, the health condition of pigs is vital to farmer's income and inevitably influence customers' health. It is challenging to monitor the pigs' health condition individually by using traditional approaches. It is common for diseases to spread from a single pig to nearly all the pigs living in the same pigsty. By adopting the technology of microchips to measure the drinking behavior of individual pigs housed in a group, it is possible to identify a pig's health and productivity state. This kind of behavior is a good indicator of a pig's overall health. Compared to traditional visual observations to determine the pig's health state, RFID-based monitoring of pig drinking behavior is a feasible and more efficient option.
Wildlife.
Using microchips in wild animals in biology began with fisheries studies to determine the efficacy of this method for measuring fish movement. Later, studies that use microchips to track wild animals expanded over the years, including researches on mammals, reptiles, birds, and amphibians. Compared with previous marking and tagging techniques used to identify wild animals before the advent of microchips, such as ear tags and color-coded leg bands, microchips are visually less obvious and less likely to be detected by prey and predators. Due to the fact that traditional identifications are on the exterior of the animal, tags can be lost, scars can heal and tattoos can fade.
Other useful and significant information can be collected by microchips. Chipped wild animals that are recaptured can provide information on growth rate and change of location, as well as other valuable data such as age structure, sex ratios, and longevity of individuals in the wild. Other researches on small mammals like rats and mice also adopt this technology to determine body temperature of terminally ill animals. As microchips are internal, permanent, durable under harsh environments, and have little influence on animals, more scholars have employed microchip implantation to collect useful data on wildlife researches.
Components of a microchip.
A microchip implant is a passive RFID device. Lacking an internal power source, it remains inert until it is powered by the scanner or another power source. While the chip itself only interacts with limited frequencies, the device also has an antenna that is optimized for a specific frequency, but is not selective. It may receive, generate current with, and reradiate stray electromagnetic waves. The radio-waves emitted by the scanner activate the chip, making the chip transmit the identification number to the scanner, and the scanner displays the number on screen. The microchip is enclosed in a biocompatible glass cylinder and includes an identifying integrated circuit placed under the skin of an animal. Relevant standards for the chips are ISO 11784 and ISO 11785.
Most implants contain three elements: a 'chip' or integrated circuit, a coil inductor, possibly with a ferrite core, and a capacitor. The chip contains unique identification data and electronic circuits to encode that information. The coil acts as the secondary winding of a transformer, receiving power inductively coupled to it from the scanner. The coil and capacitor together form a resonant LC circuit tuned to the frequency of the scanner's oscillating magnetic field to produce power for the chip. The chip then transmits its data back through the coil to the scanner. The way the chip communicates with the scanner is a method called backscatter. It becomes part of the electromagnetic field and modulates it in a manner that communicates the ID number to the scanner.
These components are encased in biocompatible soda lime or borosilicate glass and hermetically sealed. Leaded glass should not be used for pet microchips and consumers should only accept microchips from reliable sources. The glass is also sometimes coated with polymers. Parylene C (chlorinated poly-dimethylbenzene) has become a common coating. Plastic pet microchips have been registered in the international registry since 2012 under Datamars manufacturer code 981 and are being implanted in pets. The patent suggests it is a silicone filled polyester sheath, but the manufacturer does not disclose the exact composition.
Use by country.
Some countries require microchips in imported animals to match vaccination records. Microchip tagging may also be required for CITES-regulated international trade in certain endangered animals: for example, Asian Arowana are tagged to limit import to captive-bred fish. Birds that are not banded and cross international borders as pets or for trade are microchipped so that each bird is uniquely identifiable.
Australia.
Microchips are legally required in the state of New South Wales, Australia.
Because the ability to trace livestock from property of birth to slaughter is critical to the safety of red meat, the Australian red meat industry has implemented a national system known as National Livestock Identification System to ensure the quality and safety of beef, lamb, sheep meat and goat meat. There are weaknesses in the current microchipping system in Australia. According to several pieces of researches in 2015, reclaim rates were significantly higher for animals with microchips than those without microchips, which is based on the statistical analysis of the raw data of dogs and cats living in Australia as well as microchipped animals. To determine the character and the frequency of inaccurate microchip data used for locating owners of stray pets, the researchers also analyzed admission data for stray dogs and cats entering shelters called RSPCA-Queensland (QLD). The results show that the problem of microchip data may reduce the possibility that a pet's owner will be contacted to reclaim the animal. It is necessary that the current microchipping system in Australia be perfect and that microchip owners update their data frequently.
France.
Since 1999, all dogs older than four months must be permanently identified with a microchip (or a tattoo, though the latter is not accepted if the animal is to leave the country).
Cats are not required to be microchipped, though 2019 recorded increased support for mandatory chipping. Instead, since 1 January 2012, all cats older than seven months require mandatory registration in the European Union database.
Israel.
Dogs and cats imported to Israel are required to be microchipped with an ISO 11784/11785 compliant 15 digit pet microchip.
Japan.
Japan requires an ISO 11784 and 11785 compliant microchip implant for dogs and cats handled by breeders and pet shops, as well as for all imported dogs and cats. Additionally, microchipping is mandatory for certain invasive species that threaten Japan’s ecosystems or agriculture, as well as for special animals classified as dangerous to human life, health, or property.
The Act on Welfare and Management of Animals (Act No. 105 of 1973) requires owners and pet sellers to register microchipped dogs and cats with the Ministry of the Environment database and update registration details as needed. When transferring ownership of a registered dog or cat, the Registration Certificate must accompany the animal. The Act prohibits microchip removal unless it poses a risk to the animal's health or falls under other exceptional cases.
The ISO 11784 standard defines a 15-digit microchip code, split into a 3-digit country code and a 12-digit National ID Code. The Japan Veterinary Medical Association introduced a system in 1995 that includes Japan’s numeric country code (392), followed by a 2-digit animal code, a 2-digit distributor code, and a unique 8-digit identification number.
New Zealand.
All dogs first registered after 1 July 2006 must be microchipped. Farmers protested that farm dogs should be exempt, drawing a parallel to the Dog Tax War of 1898. Farm dogs were exempted from microchipping in an amendment to the legislation passed in June 2006. A National Animal Identification and Tracing scheme in New Zealand is currently being developed for tracking livestock.
United Kingdom.
In April 2012, Northern Ireland became the first part of the United Kingdom to require microchipping of individually licensed dogs.
As of 6 April 2016, all dogs in England, Scotland and Wales must be microchipped.
All pet cats in England must be microchipped by 10 June 2024. Owners found not to have microchipped their cat will have 21 days to have one implanted, or may face a fine of up to £500.
United States.
Microchipping of pets and other animals is voluntary except for some legislation mandating microchipping as a means of identifying animals who have been identified as being dangerous. Though, California law requires any animal control agency, shelter or rescue to only release a cat or dog, including to the owner, if they are microchipped or will be within 30 days. In 1994, the Louisiana Department of Agriculture and Forestry (LDAF) issued a regulation requiring permanent identification (in the form of a brand, lip tattoo or electronic identification) of all horses tested for equine infectious anemia. According to the LDAF and the state veterinarian, this requirement made contributed to better determining the owners of horses displaced during Hurricane Katrina in fall 2005.
The United States uses the National Animal Identification System for farm and ranch animals, which excludes dogs and cats. In most species, except horses, an external eartag is typically used in lieu of an implant microchip. Eartags with microchips or simply stamped with a visible number can be used. Both use ISO fifteen-digit microchip numbers with the U.S. country code of 840.
Cross-compatibility and standards issues.
In most countries, pet ID chips adhere to an international standard to promote compatibility between chips and scanners. In the United States, however, three proprietary types of chips compete along with the international standard. Scanners distributed to United States shelters and veterinarians well into 2006 could each read at most three of the four types. Scanners with quad-read capability are now available and are increasingly considered required equipment. Older scanner models will be in use for some time, so United States pet owners must still choose between a chip with good coverage by existing scanners and one compatible with the international standard. The four types include:
Many references in print state that the incompatibilities between different chip types are a matter of "frequency". One may find claims that early ISO adopters in the United States endangered their customers' pets by giving them ISO chips that work at a "different frequency" from the local shelter's scanner, or that the United States government considered forcing an incompatible frequency change. These claims were little challenged by manufacturers and distributors of ISO chips, although later evidence suggests the claims were disinformation. All chips operate at the scanner's frequency. Although ISO chips are optimized for 134.2 kHz, in practice they are readable at 125 kHz and the "125 kHz" chips are readable at 134.2 kHz. Confirmation comes from government filings that indicate the supposed "multi-frequency" scanners now commonly available are really single-frequency scanners operating at 125, 134.2 or 128 kHz. In particular, the United States HomeAgain scanner didn't change excitation frequency when ISO-read capability was added; it's still a single frequency, 125 kHz scanner.
For users requiring shelter-grade certainty, this table is not a substitute for testing the scanner with a set of specimen chips. One study cites problems with certain Trovan chips on the Datamars Black Label scanner. In general, the study found none of the tested scanners to read all four standards without some deficiency, but it predates the most recent scanner models.
Reported adverse reactions.
Adverse event reporting for animal microchips has been inconsistent. RFID chips are used in animal research, and at least three studies conducted since the 1990s have reported tumors at the site of implantation in laboratory mice and rats. The UK's Veterinary Medicines Directorate (VMD) assumed the task of adverse event reporting for animal microchips there in April 2014. Mandatory adverse event reporting went into effect in the UK in February 2015. The first report was issued for the period of April 2014 through December 2015. Mandatory microchip implant of dogs went into effect in April 2016. Data sets for 2016 through 2018 have become available. Adverse reactions to microchip implants may include infection, rejection, mass and tumor formation or death, but the risk of adverse reactions is very low. Sample sizes, in rodents and dogs in particular, have been small, and so conclusive evidence has been limited.
Noted veterinary associations have responded with continued support for the microchip implant procedures as reasonably safe for cats and dogs, pointing to rates of serious complications on the order of one in a million in the UK, which has a system for tracking such adverse reactions and has chipped over 3.7 million pet dogs. A 2011 study found no safety concerns for microchipped animals with RFID chips undergoing MRI at one Tesla magnetic field strength. In 2011 a microchip-associated fibrosarcoma was reported found in the neck of a 9-year old, neutered-male cat. Histological examination was consistent with postinjection sarcoma, but all prior vaccinations occurred in the hindlegs.
The microchip is implanted in the subcutaneous tissues causing an inflammatory response until scar tissue develops around the microchip. Studies on horses are used as the basis for short inflammatory response claims, while procedures on done on small kittens and puppies. People have reported swelling and bruising at the time of the implant with itching and pinching sensations for up to two years. The broader impacts on inflammatory disorders and cancer have not been determined and most of the health risks that were defined in the FDA Guidance developed for human implants should be considered. Adverse event reporting in the US can be made by the pet owner or a veterinarian to the FDA.
The estimate for the total cat and dog population of the UK is 16 million with 8.5 million dogs subject to mandatory microchip implant. The population of dogs implanted prior to mandatory adverse event reporting February 2015 was between 60% (February 2013) and 86% (April 2016). Approximately 95% are reported to be implanted as of April 2017.
Privacy.
Unauthorized reading of microchips can present a risk to privacy and can potentially provide information to identify or track packages, consumers, carriers, or even owners of different animals. Several prototype systems are being developed to combat unauthorized reading, including RFID signal interruption, as well as the possibility of legislation. Hundreds of scientific papers have been published on this matter since 2002. Different countries have responded differently to these issues.
As early as in 1997, some scholars believed that microchip implantation was technically possible, but it was suggested that it was the time to consider strategies for preventing potentially grievous intrusion into personal privacy. It is possible that microchips implanted on animals can also lead to privacy issues or information breaches, which can lead to serious social problems.
A common misconception is that the chip can be used for location tracking of the animal, which is false.
The microchip ownership question.
The widespread adoption of microchip identification may lead to ownership disputes occurring more frequently since sometimes microchip ownership information is irrelevant according to the ownership laws. This can occur when the owner is not the one to whom the microchip ownership information belongs. This is a significant problem because client confidentiality rules generally prohibit veterinarians from divulging information about a pet without the client's permission. Furthermore, veterinarians are required to get permission from the person who registered the chip to perform a surgery on a microchipped animal, even if the animal is experiencing a severe medical emergency. The problem can be more complicated if animals with microchips are abandoned or stolen.
Protecting privacy.
The first method of protecting microchip privacy is by regularly updating information. Stray animals with incorrect microchip details are less likely to be reclaimed and when compared to pets with correct microchip details, the time taken to retrieve the pets is longer, and sometimes reuniting is impossible. Therefore, it is wise to update microchip information regularly, especially when owners move or change their phone numbers. According to research, email reminders may increase the frequency of pet owners updating their microchip information. By increasing the pet owners' updating frequency of the pets' data, the reclaim percentages of stray animals will increase and reduce the number of pets euthanized in shelters every year.
Another method of protection is by using cryptography. Rolling codes and challenge–response authentication (CRA) are commonly used to foil monitor-repetition of the messages between the tag and reader; as any messages that have been recorded would prove to be unsuccessful on repeat transmission. It is possible that some novel RFID authentication protocols for microchip ownership transfer can be adapted to protect users' privacy, which meets three key requirements for secure microchip ownership transfer. The three requirements include: new owner privacy (only the new owner should be able to identify and control the microchip), old owner privacy (past interactions between the microchip and its previous owner should not be traceable by the new owner) as well as authorization recovery (the new owner should be able to transfer its authorization rights to the previous owner in some special cases). These features can protect owners' privacy to some extent.
Manufacturers and registers.
In the United States, the history of some tag manufacturers dates back more than 30 years. Several of the major tag manufacturers are listed below:
Some RFID-USA Registers includes:
References.
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Chips (dog)
US Military dog (1940–1946)
Chips (1940–1946) was a trained sentry dog for United States Army, and reputedly the most decorated war dog from World War II. Chips was a German Shepherd-Collie-Malamute mix owned by Edward J. Wren of Pleasantville, New York. He was bred by C.C. Moore, and was the son of Margot Jute, a half collie, half German shepherd, and Husky, a malamute.
Biography.
C.C. Moore eventually gave Chips to the Wren family. Chips immediately grew attached to Wren's daughter, Gail, that he was often seen following her to school every day and laying underneath her desk. During playtime with other children, Chips was known to intervene, pulling the girls away if he thought they were in danger.
During the war, private citizens like Wren donated their dogs for duty. Chips shipped out to the War Dog Training Center, Front Royal, Virginia, in 1942 for training as a sentry dog. He was one of four dogs assigned to the 3rd Infantry Division in North Africa, Sicily, Italy, France and Germany. His handler was Pvt. John P. Rowell. Chips served as a sentry dog for the Roosevelt-Churchill conference in 1943. On July 10, 1943, Chips and his handler were pinned down on the beach by an Italian machine-gun team. Chips broke from his handler and jumped into the pillbox, attacking the gunners. The four crewmen were forced to leave the pillbox and surrendered to US troops. "There was an awful lot of noise," Rowell said. "Then I saw one fellow come out the door with Chips at his throat. I called him off before he could kill the man." In the fight, he sustained a scalp wound and powder burns. Later that day, he helped take ten Italians prisoner.
For his actions during the war, he was awarded the Distinguished Service Cross, Silver Star and Purple Heart; however, these awards were later revoked due to an Army policy preventing official commendation of animals. His unit unofficially awarded him a theater ribbon with an arrowhead for an assault landing, and battle stars for each of his eight campaigns.
In 2018, Chips was posthumously awarded the PDSA Dickin Medal for his efforts during the war. In 2019, Chips was posthumously awarded the Animals in War & Peace Medal of Bravery.
Notes.
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Dog health
Health of dogs
The health of dogs is a well studied area in veterinary medicine.
Dog health is viewed holistically; it encompasses many different aspects, including disease processes, genetics, and nutritional health, for example. Infectious diseases that affect dogs are important not only from a veterinary standpoint, but also because of the risk to public health; an example of this is rabies. Genetic disorders also affect dogs, often due to selective breeding to produce individual dog breeds. Due to the popularity of both commercial and homemade dog foods, nutrition is also a heavily studied subject.
Diseases.
Some diseases and other health problems are common to both humans and dogs; others are unique to dogs and other animals. Dogs are susceptible to various diseases; similarly to humans, they can have diabetes, epilepsy, cancer, or arthritis.
Timely vaccination can reduce the risk and severity of an infection. The most commonly recommended viruses to vaccinate dogs against are:
Infectious diseases.
An infectious disease is caused by the presence of organisms such as viruses, bacteria, fungi, or parasites (either animalian or protozoan). Most of these diseases are spread directly from dog to dog, while others require a vector such as a tick or mosquito. Certain infectious diseases are a concern from a public health standpoint because they are zoonoses (transmittable to humans)
Viral diseases.
Viral diseases in dogs can be serious, especially in kennels.
Bacterial diseases.
Bacterial diseases in dogs are usually not contagious from dog to dog; instead they are usually the result of wound colonization, opportunistic infections secondary to decreased resistance (often the result of viral infections), or secondary to other conditions (pyoderma secondary to skin allergies or pyometra secondary to cystic endometrial hyperplasia). These examples are not considered infectious diseases because they do not satisfy Koch's postulates – for example "Staphylococcus intermedius", a commonly isolated bacteria from skin infections in dogs, would not cause pyoderma when introduced to a healthy dog. In all likelihood that type of bacteria is already present on the skin of a healthy dog.
There are some bacteria that are contagious from dog to dog. The most notable of these are "Bordetella bronchiseptica", one of the causes of kennel cough, "Leptospira" sp, which cause leptospirosis, and "Brucella canis", cause of brucellosis in dogs. There are also common tick-borne bacterial diseases, including Lyme disease, ehrlichiosis, and Rocky Mountain spotted fever.
Leptospirosis is a zoonotic disease caused by bacteria of the genus "Leptospira". Humans and dogs become infected through contact with water, food, or soil containing urine from infected animals. This may happen by swallowing contaminated food or water or through skin contact, especially with mucosal surfaces, such as the eyes or nose, or with broken skin. In dogs, transmission most commonly occurs by drinking puddle, pond, or ditch water contaminated by urine from infected wildlife such as squirrels or raccoons. The liver and kidney are most commonly damaged by leptospirosis. Vasculitis can occur, causing edema and potentially disseminated intravascular coagulation (DIC). Myocarditis, pericarditis, meningitis, and uveitis are also possible sequelae.
Brucellosis in dogs is caused by "Brucella canis". It is a sexually transmitted disease, but can also be spread through contact with aborted fetuses. The most common sign is abortion during the last trimester or stillbirth. Other symptoms include inflammation of the intervertebral disc and eye (uveitis), and inflammation of the testicle (orchitis) and prostate (prostatitis) in males.
Tick-borne diseases are common in dogs. Lyme disease, or borreliosis, is caused by "Borrelia burgdorferi" and spread by "Ixodes pacificus" on the West coast of the United States and by "I. scapularis" (deer tick) in the rest of the U.S. Signs and symptoms include fever, joint swelling and pain, lameness, and swelling of the lymph nodes. It has been diagnosed in dogs in all 48 states of the continental U.S. "Ehrlichia canis", which causes canine ehrlichiosis, and "Rickettsia rickettsii", which causes Rocky Mountain spotted fever, are both spread by the American dog tick, "Dermacentor variabilis", and the brown dog tick, "Rhipicephalus sanguineous".
Fungal diseases.
One of the most common fungal diseases in dogs is ringworm, or dermatophytosis, an infection of the skin, hair, or nails. There are three fungal species that cause ringworm in dogs. About 70 percent of infections are caused by "Microsporum canis", 20 percent by "M. gypseum", and 10 percent by "Trichophyton mentagrophytes". Signs include hair loss and scaling of the skin. Treatment for localized ringworm is not always necessary as the disease is self-limiting, but the clinical course can be shortened by using topical miconazole or clotrimazole. Generalized infections, most commonly seen in immunocompromised dogs, can be treated with oral antifungal drugs such as griseofulvin or itraconazole. Infection can spread to humans.
There are several fungal diseases that are systemic in nature, meaning they are affecting multiple body systems. Blastomycosis, caused by "Blastomyces" species including "Blastomyces dermatitidis", is a fungal disease that affects both dogs and humans. It is transmitted through the inhalation of fungal spores. It is found mainly in the United States in the Mississippi River and Great Lakes areas. It has also been reported in four Canadian provinces; Saskatchewan, Manitoba, Ontario and Quebec. Signs include weight loss, cough, fever, enlarged lymph nodes, draining skin lesions, eye inflammation with discharge, blindness, and lameness. Because dogs are ten times more likely to become infected from the environment than humans, they are considered to be sentinels for the disease. Treatment requires a minimum 60–90-day course of oral antifungal medication or in severe cases intravenous antifungal injections.
Histoplasmosis, caused by "Histoplasma capsulatum", is a disease with a worldwide distribution. In the United States it is mainly found in the Mississippi and Ohio River areas, most commonly in bird and bat feces. Signs include weight loss, cough, fever, enlarged lymph nodes, and gastrointestinal symptoms. Coccidioidomycosis, caused by "Coccidioides immitis", is found in arid and semi-arid regions of Central and South America, Mexico, and southwestern United States. Signs include weight loss, fever, cough, enlarged lymph nodes, and lameness.
Parasites.
Veterinary parasitology studies both external and internal parasites in animals. External parasites, such as fleas, mites, ticks and mosquitoes can cause skin irritation and are often carriers of other diseases or of internal parasites.
Genetic diseases.
Genetic conditions are a problem in some dogs, particularly purebreds. For this reason many of the national kennel clubs require that dogs with certain genetic illnesses or who are deemed to be carriers cannot be registered. Some of the most common conditions include hip dysplasia seen in large breed dogs; von Willebrand disease a disease that affects platelets that is inherited in Doberman Pinschers; entropion a curling in of the eyelid seen in Shar Peis and many other breeds; progressive retinal atrophy inherited in many breeds; deafness and epilepsy known to be inherited in Belgian Shepherd Dogs, German Shepherd Dogs, Cocker Spaniels, and St. Bernards.
Subaortic stenosis, or SAS, is a genetic ailment that causes a narrowing of the passage of blood between the heart and the aorta. This leads to heart problems and sometimes sudden death. It affects larger breeds such as the Newfoundland dog and the Golden Retriever. In some dogs, such as collies, the blue merle or harlequin coloring is actually the heterozygote of a partially recessive gene preventing proper development of the nervous system; therefore, if two such dogs are mated, on the average one quarter of the puppies will have severe genetic defects in their nervous systems and sensory organs ranging from deafness to fatal flaws.
Skin diseases.
Skin diseases are very common in dogs. Atopy, a chronic allergic condition, is thought to affect up to 10 percent of dogs. Other skin diseases related to allergies include hot spots and pyoderma, both characterized by secondary bacterial infections, food allergy, ear infections, and flea allergy dermatitis. Canine follicular dysplasia is an inherited disorder of the hair follicles resulting in alopecia (baldness). Mange is an infectious skin disease caused by mites. Endocrine diseases such as hypothyroidism and Cushing's syndrome can also manifest as skin problems like alopecia or recurring bacterial infections. Another class of integumentary malady is hygromas, a swelling typically on or near the elbow joint. Nutrition may also play a role in skin disease, as deficiencies in certain nutrients may result in scaling, redness, oiling, balding, and/or itching of the skin.(See dog skin disorders for specific nutrients that impacts skin)
Physical elements of certain dog breeds also affect susceptibility of individuals to skin problems, such as wrinkled skin or excessive skin folds. For instance, skin-fold dermatitis is a skin infection more prevalent in breeds such as the bulldog, cocker spaniel, and English Springer spaniel.
Orthopedic diseases.
Orthopedic diseases in dogs can be developmental, hereditary, traumatic, or degenerative. Because of the active nature of dogs, injuries happen frequently. One of the most common of these is an anterior cruciate ligament injury, a condition which often requires surgery. Bone fractures are a frequent occurrence in outdoor dogs due to trauma from being hit by cars. Degenerative joint disease is common in older dogs and is one of the most likely reasons for prescription of non-steroidal anti-inflammatory drugs.
Hereditary orthopedic diseases are mainly found in purebred dogs. Hip dysplasia is a common problem that primarily affects larger breeds. Hip dysplasia is a defect in the shape of the hip joint which can, depending on the degree of hip luxation, be quite painful to the dog as it ages. Over time it often causes arthritis in the hips. Dysplasia can also occur in the elbow joint. Luxating patellas can be a problem for smaller breeds. It can cause lameness and pain in the hind legs.
Developmental orthopedic diseases include panosteitis and hypertrophic osteodystrophy. Panosteitis occurs in large and giant breed dogs usually between the age of five and fourteen months and manifests as fever, pain, and shifting leg lameness. Hypertrophic osteodystrophy is also seen in young large and giant breed dogs and is characterized by pain, lameness, fever, and swelling of the long bone metaphysis.
Tumors and cancer.
Both benign and malignant tumors are seen in dogs. Common benign tumors include lipomas, non-viral papillomas, sebaceous gland adenoma, and perianal gland adenomas.
Frequently seen cancers include lymphoma, melanoma, mast cell tumors (which are considered to be potentially malignant, even though they may have benign behavior), and osteosarcoma (bone cancer).
Certain breeds are more likely to develop particular tumors, larger ones especially. The Golden Retriever is especially susceptible to lymphoma, with a lifetime risk of 1 in 8. Boxers and pugs are prone to multiple mast cell tumors. Scottish terriers have eighteen times the risk of mixed breed dogs to develop transitional cell carcinoma, a type of urinary bladder cancer.
Gastrointestinal diseases.
Due to the indiscriminate nature of a dog's appetite, gastrointestinal upset is a frequent occurrence in dogs. The most common symptoms are anorexia, vomiting, and diarrhea. Foreign body ingestion can lead to acute obstruction of the gastrointestinal tract, a very dangerous condition. Acute pancreatitis can also result from dietary indiscretion.
Bloat and gastric torsion.
Gastric dilatation volvulus, or gastric torsion and bloat, primarily affects breeds with deep, narrow chests, such as Great Danes, St. Bernards, German Shepherds, Standard Poodles and Irish Setters. The stomach twists on its supporting ligaments, sealing off the exits, and the contents begin to generate gas pressure which is very painful and rapidly causes shock and necrosis of large areas of stomach tissue. It can be fatal within a few hours. Dogs who have experienced bloat are very susceptible to recurrences. Treatment involves stabilization and abdominal surgery to tack the dog's stomach down to prevent recurrence (gastropexy).
Eye diseases.
Eye diseases are common in dogs. Cataracts, canine glaucoma, and entropion are seen in dogs. Canine-specific eye diseases include progressive retinal atrophy, Collie eye anomaly, sudden acquired retinal degeneration, and cherry eye. Injury to the eye can result in corneal ulcers.
The frequency of bilateral glaucoma with a genetic base in purebred dogs is higher than in any species except humans. Cataracts in dogs either have a genetic base or can also be caused by diabetes. Nuclear sclerosis resembles a cataract but is actually a normal age-related change.
Vestibular disease.
Signs of vestibular disease include head tilt, circling, nystagmus (an abnormal movement of the eyes), and difficulty or inability to stand. These clinical signs are similar to those seen in humans experiencing vertigo. Vestibular disease may have many causes. Elderly dogs are susceptible to an idiopathic (meaning due to unknown causes) form of vestibular disease commonly called "old dog vestibular disease" or idiopathic peripheral vestibular disease. The signs may improve rapidly or take a few days. Less commonly, vestibular signs can also be caused by inner ear disease, a brain tumor, a stroke, or other causes. The major risk with idiopathic peripheral vestibular disease is that the dog is often unable to eat, drink, or go outside to urinate or defecate. These cases must receive supportive therapy of intravenous fluids and nutrition; a light sedative is sometimes administered, as the dog may be very stressed by the experience.
Heart disease.
Older, small breeds of dogs are prone to congestive heart failure due to degeneration of the mitral valve. This condition is known to be inherited in Cavalier King Charles Spaniels. Degenerative valve disease is the most common form of heart disease in dogs. Mitral regurgitation leads to turbulent blood flow and increased pressure in the left atrium. This causes increased pressure in the pulmonary blood vessels and pulmonary edema (a build-up of fluid in the lungs). Decreased output of blood by the left ventricle causes the body to compensate by increasing sympathetic tone and activating the renin–angiotensin–aldosterone system (RAAS). Increased sympathetic tone leads to increased peripheral vascular resistance and increased heart rate and contractility of the heart muscle. Chronic elevation of sympathetic tone damages the heart muscle. Activation of the RAAS results in increased retention of water and sodium by the kidneys, blood vessel constriction, and other effects that result in increased blood volume. It also results in an increase in diastolic pressure and leads to pulmonary edema. Treatment for congestive heart failure has historically focussed on two types of drugs that address these concerns: diuretics (especially furosemide), which decrease blood volume, and ACE inhibitors, which interrupt the RAAS. Recently, pimobendan – which increases the force with which the heart muscle contracts, and is also a vasodilator – is being more widely used in the treatment of congestive heart failure caused by valvular disease. A major veterinary study, called the QUEST study (QUality of life and Extension of Survival Time), published in September 2008 found that dogs with congestive heart failure receiving pimobendan plus furosemide had significantly better survival outcomes than those receiving benazepril (an ACE inhibitor) plus furosemide. However, ACE inhibitors and pimobendan have different mechanisms of action, and many veterinary cardiologists recommend they be used concurrently. Within the past decade, a new surgical technique has been developed for mitral valve repair that replaces or strengthens the mitral valve chords with polytetrafluoroethylene (PTFE) prostheses and tightens the mitral valve ring to reduce or eliminate regurgitation.
Cardiomyopathy, or disease of the heart muscle, is also seen in dogs and is associated with large breeds (the exception being Cocker Spaniels, a medium-sized breed). Dilated cardiomyopathy is seen in Great Danes, Irish Wolfhounds, St. Bernards, Dobermanns, Boxers, and other large breeds. Dobermanns, in addition to heart muscle failure, are prone to ventricular arrhythmias. Boxer dogs are predisposed to a unique cardiomyopathy with clinical and histological changes analogous to human arrhythmogenic right ventricular cardiomyopathy (ARVC). The disease has been termed "Boxer cardiomyopathy" or "Boxer ARVC", and is characterized by development of ventricular tachyarrhythmias. Affected dogs are at risk of syncope and sudden cardiac death. Myocardial failure and congestive heart failure are rare manifestations of this disease.
In 2018, the U.S. Food and Drug Administration (FDA) issued a report citing a possible link between certain diets and canine dilated cardiomyopathy (DCM) in dog breeds without the genetic predisposition. Researchers at University of California, Davis School of Veterinary Medicine announced the results of their own study in early 2019, confirming the connection and identifying a particular concentration found among Golden Retrievers. Diet-related DCM is associated with grain-free and/or legume-rich diets, as well as "boutique" dog foods containing exotic ingredients (such as bison or kangaroo meat). In the treatment of dietary DCM, food change and taurine supplementation is typically indicated, in addition to traditional medical treatments as needed.
Other diseases and psychological issues.
Other diseases affecting dogs include endocrine diseases, immune-mediated diseases, and reproductive diseases. Diabetes mellitus, Cushing's syndrome, Addison's disease, and hypothyroidism are the most common endocrine diseases. Immune-mediated hemolytic anemia is a devastating disease that causes severe anemia in dogs through red blood cell destruction by the immune system. It has been associated with vaccinations and certain drugs, although many cases are idiopathic. A similar but less severe immune disease is immune-mediated thrombocytopenia, characterized by destruction of platelets by the immune system. Clinical signs include bruising and petechiae (pinpoint bruising, often seen in the mouth). Common reproductive diseases include pyometra (distension of the uterus with pus), mammary tumors, and benign prostatic hyperplasia.
Psychological anxieties affecting dogs include noise phobia and separation anxiety.
Toxic substances.
Some common sources of toxins that pets encounter include some plants, human medications and cosmetics, cleaning products, and even some foods.
Dangerous foods.
Some foods consumed safely by humans are harmful to dogs:
Chocolate.
Cocoa within chocolate contains theobromine, a chemical stimulant that, together with caffeine and theophylline, belongs to the group of methylxanthine alkaloids. Dogs are unable to metabolize theobromine effectively. If they eat chocolate, the theobromine can remain in their bloodstreams for days, and dogs may experience fast heart rate, severe diarrhea, epileptic seizures, heart attacks, internal bleeding, and eventually death. One ounce (oz) of milk chocolate contains 44 - 55 milligrams (mg) of theobromine, and baker's chocolate contains 393 mg of theobromine. The lethal dose for 50% of dogs (LD50) is 100 – 200 mg per kilogram (kg) of body weight, yet some dogs will exhibit signs of toxicosis after ingesting as little as 20 mg per kg. In case of accidental intake of chocolate, especially involving a smaller dog, contact a veterinarian or animal poison control immediately; it is commonly recommended to induce vomiting within two hours of ingestion. Treatment protocol also includes intravenous fluid therapy and/or administration of activated charcoal. Large breeds are less susceptible to chocolate poisoning, but can still die after eating four ounces of chocolate.
Carob treats are often available as dog treats; these are unrelated to chocolate and are safe.
Grapes and raisins.
Grapes and raisins can cause acute kidney failure in dogs The exact mechanism is unknown, nor is there any means to determine the susceptibility of an individual dog. While as little as one raisin can be toxic to a susceptible dog, some other dogs have eaten as much as a pound of grapes or raisins at a time without ill effects. The affected dog usually vomits a few hours after consumption and begins showing signs of kidney failure three to five days later. A mycotoxin is suspected to be involved, but one has not been found in grapes or raisins ingested by affected dogs. Salicylate, tartaric acid, or potassium bitartrate have also been implicated. The reason some dogs develop kidney failure following ingestion of grapes and raisins is not known. The most common pathological finding is proximal renal tubular necrosis.
Onions.
Onions cause hemolytic anemia in dogs and cats. Allyl propyl disulfide has been reported as being considered to be the main cause of onion poisoning in dogs. Alkyl thiosulfate and N-propyl disulfide have also been implicated. Thiosulfate levels are not affected by cooking or processing. Occasional exposure to small amounts is usually not a problem, but continuous exposure to even small amounts can be a serious threat.
Plants in the genus "Allium" (onions, scallions, garlic, leek, chives, etc.) in general contain varying levels of organosulfoxides compounds including the two mentioned above. These chemicals are responsible for their signature spicyness, but also causes oxidative damage to red blood cells of dogs and cats. Poisoning have been reported from many such plants, with symptoms ranging from diarrhea and vomiting to pale gums and hemolysis.
Nutmeg.
Nutmeg is highly neurotoxic to dogs and causes seizures, tremors, and nervous system disorders which can be fatal. Nutmeg's rich, spicy scent is attractive to dogs which can result in a dog ingesting a lethal amount of this spice. Eggnog and other food preparations which contain nutmeg should not be given to dogs.
Macadamia nuts.
Macadamia nuts can cause non-fatal stiffness, tremors, hyperthermia, and abdominal pain. The exact mechanism is not known. Most dogs recover with supportive care when the source of exposure is removed.
Hops.
Hops, a plant used in making beer, can cause malignant hyperthermia in dogs, usually with fatal results. Certain breeds, such as Greyhounds, seem particularly sensitive to hop toxicity, but hops should be kept away from all dogs. Even small amounts of hops can trigger a potentially deadly reaction, even if the hops are "spent" after use in brewing. The precise causative chemical is unknown: for now it is presumed that one of the chemicals in hops acts as a uncoupling agent in dogs.
Yeast.
Ingestion of yeast, for example in uncooked bread dough, can cause intestinal obstruction. The yeast can also cause fermentation internally, resulting in ethanol (alcohol) poisoning.
Xylitol.
Xylitol is a sugar substitute used in chewing gum, chewable vitamins, candy, toothpaste, and other products. Although a small preliminary study indicated xylitol may be safe for dogs, other studies show significant toxicity. There have been cases of foods, candies and gums containing xylitol causing toxic or even fatal liver damage in dogs. Ingestion may cause hypoglycemia.
Avocado.
Avocado leaves, bark, skin, and pit are known to be harmful to a wide range of animals, including dogs and cats. Death can occur from a sufficiently high dose. The flesh of the fruit is not generally considered toxic to the two animals.
Common household substances.
Some common household chemicals are particularly dangerous to dogs:
 Toxic in humans, dogs, and cats alike. Extremely dangerous to dogs (and children) due to its sweet taste. The antifreeze itself is not toxic, but is metabolized via the liver to the toxins glycolate and oxalate, which cause intoxication and vomiting, metabolic acidosis, and finally acute kidney failure leading to seizures and death. By the time clinical signs are observed, the kidneys are usually too damaged for the dog to survive, so acting quickly is important. Immediate treatments include inducing vomiting by using apomorphine or dilute hydrogen peroxide solution (if this can be done shortly after ingestion), but these merely reduce the amount absorbed – immediate veterinary treatment is still usually imperative due to the high toxicity of the compound. Medical treatments may include fomepizole (preferred treatment) which competes favorably with the toxin in the body, ethanol which competes favorably in the liver long enough to allow excretion to take place, activated charcoal to further reduce uptake of undigested product, and hemodialysis to remove toxins from the blood. Dogs should not be allowed access to any place in which an antifreeze leak or spill has happened until the spill is completely cleaned out. Some brands of antifreeze contain propylene glycol instead of ethylene glycol for lower toxicity. Others are marketed as being less attractive to animals.
 Isopropanol, methanol (common in household products), and ethanol (common in alcoholic beverages and rotten fruits) are all toxic to dogs. Isopropanol found in rubbing alcohol has twice the toxicity of ethanol; however, methanol found in windshield washer fluid does not have the same retinal and neuronal toxicity on dogs as it does to humans and primates due to the differences in the way its metabolite formic acid is processed.
 The effect of ethanol on dogs and cats is similar to its effect on humans, also causing intoxication. Death is unlikely given supportive care (only one death is known). Ethanol is also an antidote for ethylene glycol poisoning.
 Rodenticide is commonly found in the house or garage. This anticoagulant class of poison works by depleting stores of Vitamin K in the body; without these stores, blood cannot clot properly. Clinical signs of poisoning include depression, weakness, difficulty breathing, bruising, and bleeding from any part of the body. These clinical signs often take 3 to 4 days to appear. A blood test will confirm that the blood is not clotting properly. If the poison has only recently been ingested (within 2 to 3 hours), the dog should be given apomorphine or hydrogen peroxide to induce vomiting. Activated charcoal can be given to absorb any remaining poison in the gastrointestinal tract. Then the dog is given Vitamin K supplementation for 3 to 4 weeks, depending on the type of poison. At the end of treatment, the clotting times should be tested again. The prognosis is good in these cases. However, if the dog is already showing signs of poisoning, it is too late to try to remove the poison from the body. A whole blood transfusion or plasma is given to treat the anemia and to try to control bleeding. Vitamin K is also given. The prognosis is poor in these cases.
 Mouse and rat poisons containing cholecalciferol cause hypercalcemia and hyperphosphatemia in dogs. Clinical signs include depression, loss of appetite, vomiting blood, weakness, and shock. Treatment is as above for recent exposure. When hypercalcemia occurs (which can take 1 to 2 weeks), treatment is with intravenous fluids (saline), diuretics, corticosteroids, and calcitonin. Long term prognosis is good once the dog is stabilized.
 Ingestion can cause anxiety, muscle twitching, seizures, rapid heart rate, dilated pupils, hypersalivation, vomiting, diarrhea, and high fever due to the metaldehyde present. Treatment involves gastric lavage, intravenous fluid administration, and/or administration of activated charcoal.
Over-the-counter medications.
Poisoning with pain medications is common. Aspirin, paracetamol/acetaminophen (Tylenol), ibuprofen (Advil), and naproxen (Aleve) can all cause severe clinical signs in dogs, including vomiting blood, diarrhea, and abdominal pain. Specifically, aspirin can cause metabolic acidosis and bleeding disorders, acetaminophen can cause liver disease at high doses (the toxic dose is 150 mg per kilogram of body weight), ibuprofen can cause kidney disease, and naproxen can cause ulcers in the stomach, which can perforate. Treatment depends on the clinical signs and often involves inducing vomiting, gastric lavage, intravenous fluid diuresis, and supportive care. The antidote for acetaminophen toxicity is N-acetylcysteine.
Public health risks.
Most diseases that affect dogs or humans are not transferable between the two species. Diseases that can be transmitted from animals to humans are termed zoonoses. A well-known zoonosis is rabies, a viral infection transmitted through a bite. A common bacterial zoonosis is leptospirosis, transmitted through urine. Some of the most important zoonoses are parasitic. Zoonotic intestinal parasites transmitted through contact with feces include "Toxocara canis" (the canine roundworm), which causes toxocariasis, visceral larva migrans, and ocular larva migrans, and hookworms, which can cause cutaneous larva migrans. Zoonotic skin parasites include scabies, caused by the mite "Sarcoptes scabiei". The most common zoonotic fungal disease is ringworm, caused in this case by "Microsporum canis".
Preventive medicine.
Vaccinations.
Vaccinations are an important preventive animal health measure. The specific vaccinations recommended for dogs varies depending on geographic location, environment, travel history, and the activities the animal frequently engages in. In the United States, regardless of any of these factors, it is usually highly recommended that dogs be vaccinated against rabies, "canine parvovirus", canine distemper, and infectious canine hepatitis (using "canine adenovirus type 2" to avoid reaction). The decision on whether to vaccinate against other diseases, including leptospirosis, Lyme disease, "Bordetella bronchiseptica", "parainfluenza virus", and "canine coronavirus", should be made between an owner and a veterinarian, taking into account factors specific to the dog.
Dentistry.
Dental disease is one of the most common diseases in dogs. Accumulation of plaque, and subsequently tartar, leads to gingivitis, and then periodontitis (gum disease). Periodontitis leads to loss of the bony attachment of the teeth, and tooth loss. Preventive measures include tooth brushing, providing an appropriate diet (avoiding tinned and other soft foods, and providing dental chew treats), and dental scaling and polishing. Cavities are uncommon in dogs.
Heartworm, flea or tick preventives.
Once-a-month topical products and oral medications are the most commonly used products to kill and prevent heartworm infection and flea or tick infestations.
Nutrition and obesity.
Feeding table scraps to a dog is generally not recommended, at least in excess. Just as in humans, a dog's diet must consist of the appropriate mix of nutrients, carbohydrates, and proteins to give them the minerals and vitamins that they need. Dogs get ample correct nutrition from their natural, normal diet; wild and feral dogs can usually get all the nutrients needed from a diet of whole prey and raw meat. In addition, a human diet is not ideal for a dog: the concept of a "balanced" diet for a facultative carnivore like a dog is not the same as in an omnivorous human. Dogs will usually eat all the scraps and treats they are fed: usually too much food. While not all human delicacies are acutely toxic to dogs (see above), many have the same chronically unfortunate results as they do for humans.
Obesity is an increasingly common problem in dogs in Western countries. As with humans, obesity can cause numerous health problems in dogs (although dogs are much less susceptible to the common cardiac and arterial consequences of obesity than humans are). According to a study published in the "Journal of Veterinary Internal Medicine", the prevalence of obesity in dogs is between 22 and 40 percent.
Obesity may also be caused by some diseases, such as Cushing's disease or hypothyroidism.
Dog treats.
Dog treats are often given to pets as a reward or just to let them chew on a bone, which works their jaw muscles and helps keep their teeth clean. Although dog treats carry high benefits for dogs' teeth, they can also be a source of problems like obesity when given excessively, especially human table scraps.
The type of food given directly affects the tendency of a dog to become overweight. Table scraps, treats, and even premium high-energy dog foods can contribute to obesity. Therefore, it is highly important to closely monitor the quantity of treats that a dog gets especially when the dog's activity is diminished. Dog treats are more likely to be linked to obesity in old dogs, since in their old age they are less likely to be active and exercising. Active dogs require and use more calories.
Coprophagia.
Some dogs may attempt to consume feces. Some consume their own or other dogs' feces; others seem to prefer cat feces (which, due to the feline digestive system, are high in protein and consumed by many animals in the wild.) This can be harmful if the feces has any pathogens or parasites or contain excreted drugs.
Vitamins and supplements.
It is not yet clear whether or not vitamins and supplements should be administered in dogs—opinions among veterinarians vary widely. While some think that vitamins and supplements are necessary and can improve the health of a dog, others believe that they are unnecessary and may harm the dog. According to the U.S. Food and Drug Administration (FDA), dogs receive a complete and balanced diet from the commercially processed dog food alone. Pet owners who give their dogs homemade diets may incorporate extra vitamins and supplements.
Between approximately 10 and 30 percent of dogs in the United States receive nutritional supplements. A survey of U.S. pet owners in 2006 found that the most commonly used supplements were multivitamins and chondroprotective agents.
Overdoses of vitamins can be harmful in dogs. As an example, calcium in excess can cause bone problems, especially in the large-breed dogs. Over-supplementation of vitamins A and D can cause vitamin toxicity in dogs. Excess vitamin A can cause dehydration, joint pain and can also harm the blood vessels, while too much vitamin D can cause muscular atrophy, loss of appetite and many other health-related problems.
Reproductive health.
Spaying and neutering.
Spaying (females) and neutering (males) refers to the sterilization of animals, usually by removal of the male's testicles or the female's ovaries and uterus, to eliminate the ability to procreate and reduce sex drive. Neutering has also been known to reduce aggression in male dogs, but has been shown to occasionally increase aggression in female dogs.
Animal control agencies in the United States and the ASPCA advise that dogs not intended for further breeding should be spayed or neutered so that they do not have undesired puppies.
Because of the overpopulation of dogs in some countries, puppies born to strays or as the result of accidental breedings often end up being killed in animal shelters. Spaying and neutering can also decrease the risk of hormone-driven diseases such as mammary cancer, as well as undesired hormone-driven behaviors. However, certain medical problems are more likely after surgery, such as urinary incontinence in females and prostate cancer in males. The hormonal changes involved with sterilization are likely to somewhat change the animal's personality, however, and some object to spaying and neutering as the sterilization could be carried out without the excision of organs.
It is not essential for a female dog to either experience a heat cycle or have puppies before spaying, and likewise, a male dog does not need the experience of mating before neutering.
Female cats and dogs are seven times more likely to develop mammary tumors if they are not spayed before their first heat cycle. The high dietary estrogen content of the average commercial pet food may be contributing factors in the development of mammary cancer, especially when these exogenous sources are added to those normal estrogens produced by the body. Dog food containing soybeans or soybean fractions have been found to contain phytoestrogens in levels that could have biological effects when ingested longterm.
References.
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Sergeant Chip
"Sergeant Chip" is a science fiction novella by American writer Bradley Denton, originally published in "The Magazine of Fantasy & Science Fiction" issue of September 2004. It was the winner of the 2005 Sturgeon Award, and was nominated for the 2005 Hugo Award for Best Novella.
Plot summary.
The story is told from the point of view of Chip, a specially trained military dog that has been implanted with a microchip that allows him to communicate with his trainer, Captain Dial. The two of them put on many military demonstrations until they are called to active duty in the war. In the war they are caught in an unexpected ambush and eventually come to realize who the "real" enemy is.
References.
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Champ (dog)
Pet dog of the Biden family (2008–2021)
Champ (November 11, 2008 – June 19, 2021) was a German Shepherd owned by Joe Biden's family. He joined them in living at the White House in 2021. Champ was the older of the two German Shepherds the Bidens owned at the start of his presidency. The younger German Shepherd was Major.
Biography.
Biden promised his wife he would purchase a dog after the 2008 presidential election, irrespective of whether he and Barack Obama won the race. Jill Biden taped different pictures of dogs on seats of Biden's campaign plane for him to see. He purchased the dog as a puppy from a breeder in Pennsylvania, born November 11, 2008. It was named Champ by his granddaughters. Champ's name reminded Biden of advice given to him by his father, who said, "Any time you get knocked down, champ, get up!" Biden has an affinity for German Shepherds, having trained them in the past. Biden would give children small plush toys of Champ during his vice presidency.
Champ lived at Number One Observatory Circle during Biden's tenure as vice president. On January 24, 2021, four days after Biden's inauguration as president, Champ and Major, the Bidens' younger German Shepherd, moved into the White House.
On June 19, 2021, the White House announced that Champ had died in Wilmington, Delaware. "In our most joyful moments and in our most grief-stricken days, he was there with us, sensitive to our every unspoken feeling and emotion". the statement read. "We love our sweet, good boy and will miss him always." According to the White House statement, Champ "passed away peacefully at home".
References.
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Champ and Major
Dogs owned by Jill and Joe Biden

Small Dog Electronics
Small Dog Electronics is an American consumer electronics and information technology consulting business based in Burlington, Vermont. Founded and operated by Don Mayer, the business has grown from a small computer repair and reselling business into an Apple Premier Partner and manufacturer of iPod accessories like speakers and headphones. Most of the firm's employees bring their pet dogs to work each day.
In November 2019, Small Dog Electronics closed its original Waitsfield location, moving to a new location in Burlington, Vermont.
References.
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Japanese Chin
The Japanese Chin (, ), also known as the Japanese Spaniel, is a toy dog breed, being both a lap dog and a companion dog, with a distinctive heritage.
History.
While most believe that the source breed for the Japanese Chin originated in China, the route by which the Chin arrived in Japan is a widely debated topic. One story claims that the dogs were given to the Japanese royalty in AD 732 as gifts brought by Kim Jangson (), an envoy from the kingdom of Silla on the Korean peninsula. Others maintain that they were given as gifts to the Empress of Japan as early as the middle of the sixth century or by the seventh century. Still others claim that the Chin first arrived in Japan around the year AD 1000.
In 1613, the Japanese Chin was brought to England. In 1853 one was acquired by American naval officer, Matthew Calbraith Perry. Since 1868 they have been lap dogs to ladies of the upper class and today are companion dogs.
Appearance.
The Japanese Chin stand about approximately in height at the withers for male dogs, with bitches being slightly taller. The Fédération Cynologique Internationale gives no weight requirement for the Chin. Its distinctive expression is characterized by a large rounded broad head, large wide-set dark eyes, a very short broad muzzle, ear feathering, and evenly patterned facial markings.
Coat and color.
Japanese Chin are very cat-like in both appearance and traits.
Most dogs have two types of hair in their coat: an under and over coat. However, the Japanese Chin only has an over coat. An adult coat can take up to two years to completely grow in and can be either black and white, red and white (including all shades of sable, lemon, or orange), or tricolour (black and white with reddish tan points) As of 11 November 2011, the colors not listed in the breed standard are grounds for disqualification in competitions.
The dogs have a dot or a line on their forehead, which is believed in Japanese history to be the touch of Buddha.
Temperament.
This breed's attitude has been compared to that of cats more often than other breeds: it is alert, intelligent, and independent, and it uses its paws to wash and wipe its face. Other cat-like traits include their preference for resting on high surfaces, their good sense of balance, and their tendency to hide in unexpected places. Japanese Chin are loyal to their owners and are typically a friendly breed. While Japanese Chin prefer familiar surroundings, they also do well in new situations. This, alongside their friendly demeanor, makes them good therapy dogs. Early socialization of Japanese Chin puppies leads to a more emotionally well-balanced Chin that is more accepting of different situations and people.
Japanese Chin are defensive animals and thus although they are usually quiet, they will bark to alert the arrival of a visitor or to draw attention to something out of the ordinary.
Japanese Chin were also bred for the purpose of entertaining their owners. While typically calm, they are well known for performing many tricks such as the "Chin Spin", in which they turn around in rapid circles; dancing on their hind legs while pawing their front feet, clasped together, in the air; and some even "sing", a noise that can range from a low trill to a higher, almost operatic noise.
Health.
A 2024 UK study found a life expectancy of 12.5 years for the breed compared to an average of 12.7 for purebreeds and 12 for crossbreeds.
Common health issues in the Japanese Chin include luxating patellas (slipping kneecaps), cataracts, and early-onset heart murmurs.
References.
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Happy Dog Monument
Statue in Warsaw, Poland
The Happy Dog Monument (Polish: "Pomnik Szczęśliwego Psa") is a statue of a Golden Retriever dog in Warsaw, Poland, placed in the Mokotów Field park complex, within the district
of Ochota. It was designed by Bogna Czechowska, and unveiled on 2 October 2004.
History.
The monument was designed by Bogna Czechowska, and proposed by "Cztery Łapy" pet magazine. It was unveiled on 2 October 2004, during the Warsaw Dog Parade organised by the magazine, in commemoration of the World Animal Day.
Characteristics.
The statue is placed in the Mokotów Field park complex. It depicts a sitting Golden Retriever dog, based on an individual named Lokat that was a therapy dog. The idea behind the monument was to depict a happy animal, which came from a loving household.
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Chippiparai
The Chippiparai is a breed of sighthound from the State of Tamil Nadu in southern India.
The Chippiparai has typical streamlined sighthound features with long legs and a lean and lithe frame built for speed. The breed is usually white in colour, although other colours can be found. It averages in height at the withers, dogs averaging and bitches . A hardy breed, the Chippiparai is reputed to prefer a single master, shunning food and pats from anyone except its handler. The Chippiparai is often regarded as the most intelligent and biddable of India's native dog breeds.
The Chippiparai is most frequently found in the regions of Virudhunagar, Tirunelveli, Thenkasi, Thoothukudi, and Madurai, thought to be descended from Salukis the breed was historically kept by royalty in southern India, its name derived from a village name of Sippipparai in Vembakottai Taluk of Virudhunagar District. The Chippiparai was traditionally used to hunt small game, predominantly hare. Due to its intelligence and biddable nature, the breed has successfully been trained as police dogs.
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Pet recovery service
Service to reunite lost pets with their owners
The goal of a pet recovery service is to reunite owners with their lost or stolen pets.
Pet recovery.
Without identification tags.
A wide variety of pet recovery services exist, including online services to search for lost pets. Less traditional services for searching for lost pets include the use of a bloodhound, a pet detective, or sites that offer a bulk-calling computer that can quickly alert neighbors by phone.
With identification tags.
External identification.
Forms of external identification include collar tags with identifying information, or QR codes with pet information or pet recovery service information. The pet could be tracked through a service toll-free number or web address on the tag; the service accesses the pet and owner information in a database via a number or QR code. Some pet identification tags include the owner's address or phone number, which can be used to reunite the pet with its owner. There are also registry database services based on tattoo registries.
Electronic tracking devices.
Recovery service providers use collar-attached electronic tracking devices to reunite the pet with its owner. The contract may also include recovery services, which eliminates any need to rely on a stranger encountering the pet. However, at least one device also calls for help from anyone nearby. This depends on whether the device is GPS, radio, or Bluetooth.
Microchip implant.
Since the early 1990s, advocates have promoted the under-skin I.D. tag or microchip implant as a collar-free solution for pet recovery. Veterinary services, animal shelters, and some individuals have chip scanners. In the U.S., such services are unregulated, and several types of chips have emerged with only some adhering to the pertinent ISO standards, ISO 11784 and ISO 11785. Originally, each type had its own scanner with no ability to read or even detect other types. However, there is a trend toward universal scanners that can read all types. Unlike the identifying collar tags mentioned above, the appropriate database keeper cannot always be determined from the ID number, complicating the task of returning the pet to its owner.
Metasearch engines.
As an aid to the pet finder in this situation, chip registry metasearch engines have been established. Two that have been available at least since 2003 are Europetnet, which has a large number of participating European registries, and Petmaxx, a worldwide registry service. In 2009, the metasearch engine, sponsored by the American Animal Hospital Association, was put online. Most of the major U.S. registries are now participants.
Pets are reunited with their owners by the stray pet's code, whose information is accessed via a database. The services are only accessed where chip registry services have decided to interface with metasearch engine services.
Successful metasearch engines connect to all the available regist