Effects of Various Postpartum Treatments upon the Reproductive Efficiency of Dairy Cows1,2

Abstract

Summary The effects of postpartum treatments on subsequent reproductive performance were observed on 305 reproductive cycles of 137 Holstein cows from 1953 to 1957. Cows were assigned to treatment lots, as they freshened, within Group A, normal calving, or Group B, abnormal calving (dystocia and/or placenta retained more than 12 hr.). Animals in Group A, Lot I, received no treatment, while those in Lot II received one intrauterine administration of one oblet containing 500mg. Aureomycin HCl within one day after parturition. In Group B, the animals usually were treated daily until cured. Lot I received oblets containing 15g. sulfamethazine (Sulmet) and Lot II received only Aureomycin. A no-treatment lot, Lot III, was added to Group B after the experiment had been in progress about 2 yr. Owing to the few observations and the great variation in the behavior among animals in this lot, the data were evaluated by case studies. Among Group A cows, no significant differences in breeding efficiency due to treatment could be demonstrated between Lots I and II. Cows in Group B responded more favorably to Aureomycin than to Sulmet treatments (P ca . 0.09 for conception interval). The breeding efficieney of cows in Lot B-II approached the level of normal cows. It was shown that some abnormally parturient cows must be treated, to survive.