Longitudinal study of humoral immunity to bovine coronavirus, virus shedding, and treatment for bovine respiratory disease in pre-weaned beef calves

Table 2 Summary of sample collection and testing performed

Collection time	Samples collected	Number sampled	Testing
Birth	Blood	Subset^a, n = 169	n = 169 Maternal anti-BCV IgG
Initial vaccination	Blood, NS^b	All study calves^c	n = 60 each herd, 180 total Blood: anti-BCV IgG NS: subclinical virus shedding
Preconditioning	Blood, NS	All study calves	n = 60 each herd, 180 total Blood: anti-BCV IgG NS: subclinical virus shedding
Weaning	Blood, NS	All study calves	n = 60 each herd, 180 total Blood: anti-BCV IgG NS: subclinical virus shedding
At time of treatment for BRD	Blood, NS	n = 234 (including mass treatments)	Blood: anti-BCV IgG NS: detection of viral and bacterial pathogens

^aBlood was collected between 18 and 48 h after birth from a small subset of calves for which both birth and the first nursing episode were observed to ensure chance for colostrum uptake
^bNS, nasal swabs
^c817 calves were sampled for this study, see Table 1

ISSN: 1746-6148