INFLUENCE OF CONTROLLED SUCKLING AND THE MALE EFFECT ON THE RESUMPTION OF POSTPARTUM OVARIAN ACTIVITY IN PELIBUEY SHEEP

Abstract

The effect of suckling and its interaction with the male effect on duration of postpartum anestrus in Pelibuey ewes and on live weight of the ewes and their lambs was determined. Seven days after lambing 56 adult ewes and their lambs were randomly assigned to the treatments: T1) Continuous suckling (CS; n=14); T2) Controlled suckling (RS; n=14); T3) Continuous suckling with ram (CSR; n=14); and T4) Controlled suckling with ram (RSR; n=14). A ram fitted with an apron was introduced with the ewes from day 7 to 60 postpartum for 30 min twice daily. Live weight of ewes and lambs was recorded weekly from lambing until weaning. Ovulation percentage in the first 60 days postpartum was greater in RSR (100 %; P ≤ 0.05) than in RS, CSR and CS (57.1, 64.8 and 35.7 %, respectively). Controlled suckling shortened (P ≤ 0.05) the interval lambing-first ovulation (ILFO) in RSR (42.07±2.8 days) compared with RS, CSR and CS (51.07±3.24, 50.50±3.26 and 56.71±1.73 days, respectively). No differences were found in live weight of ewes and lambs (P > 0.05). The interaction controlled suckling-male effect increased the percentage of ovulation before day 60 postpartum and shortened the ILFO, with no effect on the live weight of ewes and lambs.