Risk factors associated with exposure to bovine respiratory disease pathogens during the peri-weaning period in dairy bull calves
|Title:||Risk factors associated with exposure to bovine respiratory disease pathogens during the peri-weaning period in dairy bull calves||Authors:||Murray, Gerard M.
More, Simon J.
Clegg, Tracy A.
Cassidy, Joseph P.
|Permanent link:||http://hdl.handle.net/10197/10098||Date:||27-Feb-2018||Online since:||2019-04-24T07:30:23Z||Abstract:||Background: Bovine respiratory disease (BRD) remains among the leading causes of death of cattle internationally. The objective of this study was to identify risk factors associated with exposure to BRD pathogens during the peri-weaning period (day (d)-14 to d 14 relative to weaning at 0) in dairy bull calves using serological responses to these pathogens as surrogate markers of exposure. Clinically normal Holstein-Friesian and Jersey breed bull calves (n=72) were group housed in 4 pens using a factorial design with calves of different breeds and planes of nutrition in each pen. Intrinsic, management and clinical data were collected during the pre-weaning (d-56 to d-14) period. Calves were gradually weaned over 14 days (d-14 to d 0). Serological analysis for antibodies against key BRD pathogens (BRSV, BPI3V, BHV-1, BHV-4, BCoV, BVDV and H. somni) was undertaken at d-14 and d 14. Linear regression models (for BVDV, BPI3V, BHV-1, BHV-4, BCoV and H. somni) and a single mixed effect random variable model (for BRSV) were used to identify risk factors for changes in antibody levels to these pathogens. Results: BRSV was the only pathogen which demonstrated clustering by pen. Jersey calves experienced significantly lower changes in BVDV S/P than Holstein-Friesian calves. Animals with a high maximum respiratory score (≥8) recorded significant increases in H. somni S/P during the peri-weaning period when compared to those with respiratory scores of ≤3. Haptoglobin levels of between 1.32 and 1.60 mg/ml at d-14 were significantly associated with decreases in BHV-1 S/N during the peri-weaning period. Higher BVDV S/P ratios at d-14 were significantly correlated with increased changes in serological responses to BHV-4 over the peri-weaning period. Conclusions: Haptoglobin may have potential as a predictor of exposure to BHV-1. BRSV would appear to play a more significant role at the 'group' rather than 'individual animal' level. The significant associations between the pre-weaning levels of antibodies to certain BRD pathogens and changes in the levels of antibodies to the various pathogens during the peri-weaning period may reflect a cohort of possibly genetically linked 'better responders' among the study population.||Type of material:||Journal Article||Publisher:||BioMed Central||Journal:||BMC Veterinary Research||Volume:||14||Issue:||53||Start page:||1||End page:||11||Copyright (published version):||2018 the Authors||Keywords:||Calves; Antibodies; Bovine respiratory disease; Dairy; Exposure||DOI:||10.1186/s12917-018-1372-9||Language:||en||Status of Item:||Peer reviewed|
|Appears in Collections:||Veterinary Medicine Research Collection|
Show full item record
This item is available under the Attribution-NonCommercial-NoDerivs 3.0 Ireland. No item may be reproduced for commercial purposes. For other possible restrictions on use please refer to the publisher's URL where this is made available, or to notes contained in the item itself. Other terms may apply.