Dynamic of weight and corporal score and reproductive efficiency of the Santa Ines breed and crossbreed Suffolk ewes submited to two feeding systems and lambing of 8 months

摘要

This study was carried out with the objective of comparing the productive and reproductive efficiency of ewes in two productive systems. Ninety eight Santa Ines ewes and thirty nine crossbred Suffolk were divide in two treatments: T1- maintained on pasture, with supplementation of Pennisetum purpureum silage in dry winter, T2- maintained on pasture, with supplementation of Pennisetum purpureum silage in winter and grain ration for three weeks before and during the mating, three weeks before lambing and during the lactation. There was difference (P0.05) between initial weight (IW); (52.50 and 54.33kg) and final weight (FW); (53.53 and 55.76kg) for T1 and T2 respectively; and breed effect (P0.05): the IW was 51.46 for SI and 55.38 to crossbreed SF, and the FW was 52.36 for SI and 56.78kg for crossbreed SF. The pre-lambing weight (PL) was different only among the seasons (65.23kg for Season I, 58.15kg for Se II and 59.73kg to Se III). The after lambing weight (AL) was also different (P0.05) between breeds (SI 53.59kg and crossbreed SF 57.05 kg), and so the weight 30 days after (W30d) when SI presented 52.94 kg and crossbreed SF 55.45kg. The ewe weights 70 days (W70d) after birth were for SI 50.83 and 53.22 for crossbreed SF and the weights in the 100th day (W100d) were 51.55 and 53.61kg for SI and crossbreed SF, respectively. The initial corporal score (ICS) was higher for T2 (2.47) when compared to T1 (2.16). The final corporal scores (FCS) were 2.19 and 2.60, respectively to T1 and T2 (P0.05), but there was not difference between treatments in the pre- lambing corporal score (PCS). The ICS of 2.40 for crossbreed SF was (P0.05) higher than for SI (2.22). In the three reproductive seasons, only in Se I the SCI (2.55), SCF (2.80) and SCB (3.03) were significantly higher. However, the PCS was slower in Se III (2.10) than in II (2.47). The ewes in Se I and T1 had 72.5 % of fertility and in the T2 they had 82.5%; in Se II the females from T1 had 40.0 % and those from T2 had 53.0 %. The fertility in the Se III was 57.0% for T1 and had 81.5 % for T2. The prolificity in the Se I was 1.20 and 1.55 for T1 and T2 respectively; in the Se II 0.90 and 1.03 and for Se III, 1.11 and 1.14. It was concluded that the supplementation had increased the productive performance of ewes.