ASAS/ADSA Ruminant Nutrition: Fat Nutrition/Feed Intake

St. Croix White and Barbados Blackbelly hair sheep ewes were used to evaluate the effect of supplemental nutrition around lambing on ewe and lamb performance during the wet season on St. Croix. Beginning 14 d prior to expected day of lambing (day 0) and for 21 d postpartum, 11 ewes were fed a pelleted complete ration (17% crude protein) at a level to provide 150% of the nutrient requirements, in addition to grazing guinea grass pasture (FEED). Twelve ewes grazed pasture only (CONTROL). This study was conducted during October through January. Total rainfall during this time was 212 mm and forage dry matter ranged from .77 to 2.49 MG/ha. The 24-hr milk production of all ewes was measured on days 7, 21, 35, 49 and 63. Ewes were given 1 IU of oxytocin (i.v.) and milked by hand and separated from their lambs. Four hours later ewes were hand milked again, using oxytocin, and the milk from the second milking was weighed to determine 24-hr milk production. Ewes were exposed to sterile rams equipped with marking harnesses to detect estrus during the postpartum period. Lambs were weaned at 63 d of age. Data were analyzed by SAS using treatment and days postpartum as main effects. The CONTROL ewes lost a higher percentage (P < .05) of their pre-lambing weight during lactation than FEED ewes. There was no difference (P > .10) in milk production between FEED and CONTROL ewes. The time to first postpartum estrus was less (P < .03) in FEED than in CONTROL ewes (33.0 ± 2.5 vs 41.1 ± 2.4 d, respectively). Litter birth weight was similar (P > .10) for FEED and CONTROL ewes (4.2 ± .5 vs 4.9 ± .4 kg, respectively). Lamb weaning weight was not different (P > .10) for lambs raised by FEED or CONTROL ewes (17.3 ± .9 vs 15.8 ± .8 kg, respectively). There was no difference (P > .10) in ADG of lambs in the FEED or CONTROL groups (222.1 ± 13.6 vs 200.4 ± 11.9 g/d, respectively). Supplementation of hair sheep ewes around parturition during the rainy season in the topics does not appear to enhance ewe or lamb production traits.