Effects of Periparturient Disease on Postpartum Reproduction in Dairy Cattle
The effects of periparturient disease on postpartum reproduction and breeding efficiency were studied in 50 cows during 123 lactations over a 3-year period. The cows with periparturient diseases were 7.7 months older and produced 490 kg more milk than those with normal parturitions (P<0.05). The first ovulation occurred at 18.0 days postpartum in normal cows and at 42.0 days in abnormal cows (P<0.01). The interval from first to second ovulation was 17.7 days in normal cows and 21.9 days in abnormal cows (P<0.01). The interval from second to third ovulation was approximately normal in both groups. There was no significant difference in the occurrence of standing estrus between normal and abnormal cows (P>0.05).
Normal corpora lutea occurred during 61% of the 314 cycles, cystic corpora lutea during 17% and cystic follicles during 22%. There were significantly more corpora lutea in normal than in abnormal cows (P<0.05). The differences in the occurrence of cystic corpora lutea and cystic follicles were not significant (P<0.05). The cows with periparturient disease had a 22-day longer calving interval and required 0.6 more services for each conception (P<0.05).
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