Technical note: Productive variables of Pelibuey lambs and ewes induced to estrus with exogenous hormones and with different types of suckling
With the objective of analyzing the productive and reproductive response of lambs and ewes subjected to induced or synchronized estrus and to three different types of suckling, 60 Pelibuey ewes and their lambs were randomly assigned, at seven days postpartum, to one of three groups (n = 20); continuous suckling (AC), restricted suckling (AR) and early weaning (DP). The animals were weighed weekly from birth until the eighth week. At 30 d postpartum, the hormonal treatment applied was intravaginal progestagen (P4) plus 0.05 mg of PGF2á and 300 UI of eCG two days before the removal of P4. The percentage of estrus was higher (95%) in DP and AR groups compared with AC (60%; P < 0.05), as was fertility (DP, 80%; AR 75%) versus 40% in AC (P < 0.05), and prolificacy (lambs/ewe, 1.87 and 1.5; P < 0.05). Weight of lambs at 8 wk of age was higher for AC (16.8) and AR (16.5) than for DP (11.9 kg; P < 0.05). In conclusion, the restriction of suckling and early weaning, improved the reproductive efficiency in Pelibuey ewes. However, DP reduced weight gain of the lambs and increased their mortality rate relative to AC and AR.