IMPACT OF STARTER FEED AND FIBER COMBINATION ON RUMEN DEVELOPMENT AND PRODUCTIVITY IN NEONATAL LAMBS

Resumen

The feeding of neonatal lambs in the tropics is based on milk and low-quality forages, which limits ruminal development and productivity. The objective of the study was to evaluate the rumen development and productivity of neonatal lambs raised under three dietary regimes: a) a liquid diet based on whole cow’s milk (MILK); b) a solid diet based on fiber from low-quality forage, administrated by star grass (Cynodon nlemfuensis, FIBER); c) a solid diet based on the combination of fiber (40% FIBER and 60% starter feed, F40+SF60). Twelve 15-day-old lambs were evaluated over a 38- day period to assess: initial live weight, final live weight, dry matter intake, and daily weight gain, as well as the length, width, and number of ruminal papillae per cm2 ; the volume of the reticulum, rumen, omasum, abomasum; ruminal pH; and concentration of total bacteria. A completely randomized design was used, with three treatments and four lambs per treatment. Data were analyzed using the PROC GLM procedure in SAS and means were compared using Tukey’s test. In MILK, there was a greater number of rumen papillae in the cranial, ventral sac and ventral blind sac (p < 0.05); The number of papillae in the dorsal sac and dorsal blind sac, length and width of the ruminal papillae, reticulum volume and concentration of total bacteria were greater in F40+SF60 lambs (p < 0.05). Dry matter intake and daily weight gain were similar between the MILK and F40+SF60 dietary treatments (p < 0.05). The consumption of a combination of fiber and starter feed in neonatal lambs stimulated the development of rumen papillae, allowing weaning without affecting daily weight gain.