| Autor: |
Roche SM; ACER Consulting, Guelph, ON N1G 2W1, Canada., Ross JA; Chinook Contract Research Inc., Airdrie, AB T4A 0C3, Canada., Schatz C; Chinook Contract Research Inc., Airdrie, AB T4A 0C3, Canada., Beaugrand K; Chinook Contract Research Inc., Airdrie, AB T4A 0C3, Canada., Zuidhof S; Sjoert Zuidhof Consulting, Calgary, AB T1S 0M3, Canada., Ralston B; Lakeland College, 282075 TWP RD 262, Rocky View County, AB T4A 2L6, Canada., Allan N; Chinook Contract Research Inc., Airdrie, AB T4A 0C3, Canada., Olson M; Alberta Veterinary Laboratories Ltd., Calgary, AB T2C 5N6, Canada. |
| Abstrakt: |
This study investigated the effects of dystocia on milk production, somatic cell count, reproductivity, disease, and milk production. A total of 2159 cows across 21 dairy farms in Alberta, Canada were enrolled in this study. Multivariable models were created to explore associations between outcome variables and calving ease score. In total, 89.5% of calvings were unassisted, 6.1% were an easy pull, and 4.3% were a moderate-hard pull. Cows that had a moderate-hard pull produced 4.01 kg less milk, 0.12 kg less volume of milk fat, and 0.12 kg less milk protein per day than those that had an unassisted calving. No difference was found between calving ease groups with respect to SCC. Cows with a moderate or hard pull produced 510 kg less milk per lactation than unassisted cows. Cows with a moderate to high level of assistance at birth had a higher hazard of being culled over the duration of their lactation. Cows with an easy pull had increased odds of developing a retained placenta. It is evident that assistance at calving, particularly a moderate-hard pull, is associated with significant impacts on future milk production and risk of being culled; therefore, efforts should be made to minimize dystocia and prevent these impacts. |
