Uterine pathologies and fertility of dairy cows treated with two injections of PGF2α within the first 48 hours after calving

Abstract

The objective of this work was to evaluate the effect of two injections of PGF2α within the first 48 hours after calving to decrease the incidence of uterine pathologies and improve reproductive performance in dairy cows. Four hundred and forty five Holstein cows with average milk yield of 10 100 kg per lactation were used. On calving day, cows were assigned in two groups, according to parity. Cows in the PGF2α group (n = 180) received a dose of 500 mcg of cloprostenol sodium by intramuscular injection within the first 12 h of calving and a second injection 48 h later; cows in the control group (n = 265) received nothing. All cows were examined via rectal palpation on day 7 postpartum; the type of pathology [placental reten­tion (PR), haemorrhagic metritis (HM) and purulent metritis (PM)] was recorded. All cows were inseminated under the same reproductive program. Pregnancy diagnosis was carried out on day 45 after insemination by rectal palpation. The percent­age of cows showing PR was lower (P < 0.05) in the PGF2α group (3%) than in the control group (10%); the percentage of cows with HM and PM was similar (P > 0.05) between groups [HM (PGF2α = 28.3% vs control = 31.6%) and PM (PGF2α = 43% vs control = 42.7%)]; the average interval from calving to first estrus was lower (P < 0.05) in cows of the PGF2α group (32.5 ± 1.7 days) than in the control group (42.1 ± 2.3 days); the average interval from calving to fist service was similar (P > 0.05) between groups (PGF2α = 76 ± 1.7 vs control = 80 ± 1.7days); the pregnancy rate on day 90 postpartum was greater (P < 0.05) in PGF2α group (38%) than in the control group (24.3%). It is concluded that PGF2α injection within the first 12 h postpartum and a second one 48 h after, decreases the incidence of placental retention, shortens the calving-first estrus interval and increases pregnancy rate on day 90 postpartum.