This study aimed to quantify the variation in individual test - day milk yield and somatic cell count , risk of reproductive failure after first service of dairy cows , and risk of death of calves and heifers according to the BCV and BRSV status of the herd .
Three types of status were defined for BCV and BRSV infections ,
This study aimed to quantify the variation in individual test - day milk yield and somatic cell count , risk of reproductive failure after first service of dairy cows , and risk of death of calves and heifers according to the BCV and BRSV status of the herd .
Three types of status were defined for BCV and BRSV infections , based on 1 ) the dynamics over a 7-mo period of BCV - and BRSV - specific antibody levels in pooled milk of primiparous cows ; 2 ) the possible occurrence of presumably BCV - and BRSV - related clinical outbreaks ; and 3 ) the combination of both pieces of information .