The effect of postpartum ovarian dysfunction and endometritis on subsequent reproductive performance in high and medium producing dairy cows

Abstract

The incidence of postpartum ovarian dysfunction and endometritis and their effects on subsequent reproductive performance was compared between high and medium milk producing Holstein Friesian cows for 3 years. A total of 125 high producing cows belonged to two herds, with an average milk yield per lactation of about 9,300 to 9,700 kg and 8,600 to 8,800 kg per herd, while 97 medium producing cows belonged to four herds, with an average milk yield between 6,600 and 7,800 kg. All herds were visited every two weeks for reproductive checks. Postpartum ovarian activity was monitored by milk progesterone analysis. Incidence of postpartum ovarian dysfunction indicated by delayed first ovulation, cessation of ovarian cyclicity after the first ovulation or persistence of the corpus luteum was 36.6% in high producing cows and 36.1% in medium producing cows. Postpartum endometritis was diagnosed in 44.0% of high producers and in 32.0% of medium producers. Thus high producing cows did not necessarily show higher incidence of the postpartum reproductive disorders. Cows with postpartum ovarian dysfunction, particularly those with cessation of ovarian cyclicity after the first ovulation, showed a significantly lower first insemination conception rate (P<0.01) and required significantly longer to conceive (P<0.05) compared with cows with normal postpartum ovarian function in both high and medium producing cows. Likewise, cows with postpartum endometritis showed a 13 to 18% lower first insemination conception rate and took 7 to 12 days longer to conceive than cows with normal uterine involution. It appears that the postpartum reproductive dysfunction has adverse effects on the subsequent reproductive performance in high as well as in medium producing cows.