Abstract
Clinical signs, changes in blood characteristics, plasma estrogen and progesterone levels were investigated during the period of the 7 days before expulsion to the 3 days after expulsion in 5 cows having twins. Values obtained were compared with those of 8 cows with single birth. An average of gestation length of the cows with twins was 8 days shorter than those of the cows with single birth. At expulsion, proper handling at the dystocia was needed in 2/5 twinnings. Retained placenta occurred in all twin calvings, although in 3 cases either of the 2 placentas was discharged within 12 h after the expulsion. In many twinnings, the rectal temperature did not decrease below 38.5C before the expulsion, and increased above 39.6C after expulsion. Ligamentum sacrotuberale latum relaxated at expulsion did not fully resume to the former condition after the expulsion. Maximum values of glucose concentration before and after the expulsion in twinnings were lower than those at the same periods in the single birth. The ratios of segmentcytes to lymphocytes after the expulsion and numbers of eosinophils before and after expulsion were lower in the cows with twins. In some twinnings, a decrease in estrogen levels was slower and a slight increase in progesterone levels was observed after expulsion.
