embryonic losses, Mexican Altiplano, dairy cattle.
Objective: To determine embryonic losses between the early diagnosis and the confirmation of gestation in dairy cows from different barns for one year.
Design/Methodology/Approach: A total of 3,413 confined Holstein cows from three different dairy barns in the Mexican Altiplano (highlands) were studied. Cows were milked three times a day with an average daily production of 36.5 ± 1.5 L. Gestation diagnosis was performed by ultrasonography at 34 ± 7 d after the artificial insemination, while gestation was confirmed at 60 ± 5 d. Average pregnancy loss was determined and embryonic losses were compared taking into account barn and month.
Results: The overall average of embryonic losses was 18.8%. Neither the month factor nor the month × barn interaction affected the percentage of embryonic losses (p<0.05). Differences per barn (p<0.05) were observed and barns 1, 2, and 3 recorded losses percentages of 4 ± 1.6 %, 11.4 ± 1.6 %, and 22.9 ± 1.6%, respectively.
Study Limitations/Implications: Detailed differences between barns were not studied, since cow management was similar in all three of them. Embryonic losses must be recorded, given their significant impact on the barn.
Findings/Conclusions: There is a high variability among barns regarding embryonic losses between the early diagnosis and the confirmation of gestation. This situation may be the result of management differences, since the breed and environmental conditions were the same in all three barns.