Effect of Feeding Protein-Protected Lipid upon Growth and Reproductive Development of Yearling Heifers2,3

Abstract

Sixty prepuberal Brahman × Hereford F-l heifers were fed Coastal bermudagrass hay plus a concentrate containing zero (C) or 50% of a microencapsulated tallow (PL) for 168 days. Growth, as measured by height, length and weight gains, was similar for both feed groups. Controls had increased ruminal concentrations of total volatile fatty acids (P<.05). Protected lipidfed heifers had greater subcutaneous fat deposition (P<.005), greater intramuscular fat deposition (P<.10) and greater gain in body condition score (P<.005). Blood plasma glucose and triglyceride concentrations were similar for both treatments. Protected lipid-fed heifers tended to be more efficient in converting energy to weight gain (7.7 vs 7.9 Meal NEg/kg wt gain) than controls which required 13.7% more total feed/kg weight gain (P<.05). All heifers were bred in an artificial insemination program the last 60 days on test. Less protected lipid heifers reached puberty while on test than did control heifers [Pvs 80% (24/30), respectively]. Conception rates did not differ between groups. Copyright © 1978. American Society of Animal Science . Copyright 1978 by American Society of Animal Science.