Uterine involution and reproductive performance of lactating friesian cows treated with oxytocin and prostaglandin (PGF₂α) at calving [electronic resource].

Includes reference.

This study was carried out at Sakha Experimental Station, belonging to Animal Production Research Institute to evaluate the effects of oxytocin (OT) and prostaglandin (PG) administration within 6-12 h of calving on uterine involution and reproductive efficiency of lactating Friesian cows. Total of 15 multiparous Friesian cows with normal parturition averaging 400-650 kg live body weight, 2-7 parities and 2.5-3.5 body condition score were used in this study. Animals were divided into three groups, 5 animals in each. Animals in the 1st group were i.m. injected with saline solution (control). Animals in the 2nd and 3rd groups were administrated with an i.m. injection of 50 IU OT and 3 ml PG (Estromate). Animals in all groups were administrated during the same injection schedule (6-12 h of calving). Routine examination of the genitalia per rectum was conducted once weekly to judge the uterine involution by ultrasonography to determine diameter of uterine horns (gravid and non-gravid), uterine body, length and diameter of cervix and vaginal length. Pregnancy was diagnosed by rectal palpation on day 45 post-insemination, days open (DO) and number of services per conception (NSC) were recorded. Results showed that diameter of non-gravid horns showed insignificantly slight .reduction during postpartum period in each group. Diameter of gravid horns decreased (P<0.05) up to day 35 in control group, versus days 21 and 28 of post-partum in OT and PG groups, respectively. Diameter of the uterine body reduced (P<0.05) in OT and PG up to day 21 of post-partum as compared to day 28 in the control group, thereafter uterine horn diameter showed insignificant reduction in each group. Cervical length and diameter reduced (P<0.05) up to day 28 in the control group versus day 21 in OT and PG groups.

Summary in Arabic.

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