PRODUCTIVITY OF CREOLE SHEEP UNDER EXTENSIVE GRAZING SUPPLEMENTED ENERGETICALLY IN A CRITICAL SEASON

Abstract

The productivity of sheep was evaluated with the strategic supplementation with ground maize (Zea mays L.) or glycerin before and during mating and the last third of gestation, as well as the availability of fodder in Ignacio Allende, Mexquitic de Carmona, S. L. P. (101° 07’ W and 22° 16’ N, 2020 m of altitude). Eighteen (18) Creole sheep thoroughbred with Rambouillet and Suffolt (45.6 kg) were assigned to three treatments: T1 (native pasture), T2 (native pasture+ground maize), T3 (native pasture+glycerin). The supplement was offered during nighttime confinement, 15 days before and 15 days during mating and the last 40 days of gestation. The variables were live weight at mating (LWM) and at birth (LWB); body condition when mating (BCM) and at birth (BCB); female weight gain (FWG) and weight of lamb at birth (WB); and dry matter availability (DMA). A completely random design and Tukey test at 0.05 were used. The LWM was higher for the T2 (61.54 kg). The BCM was higher for T2 (3.5). For the LWB, T2 presented the highest value (66.30 kg). In the FWG, T3 showed the highest value (5.66 kg) and the lowest FWG was for T1 (-1.07 kg). The availability of dry matter was higher for winter (1,176.2 kg MS ha^-1); the best nutritional contribution was in spring with RP 18.3% and EB of 4.96 Mcal kg^-1.