Resumen

ZAMORA-ZEPEDA, Raquel; OLIVA-HERNANDEZ, Jorge  y  HINOJOSA-CUELLAR, José Alfonso. Energy and protein supplemented in Blackbelly x Pelibuey ewe lambs under grazing. Nova scientia [online]. 2015, vol.7, n.15, pp.245-264. ISSN 2007-0705.

The ewe lamb fed under grazing without supplemental feed has low average daily weight gain (ADWG). This situation retarded growth and may influence age and body weight (BW) at puberty as well as the age at a specific slaughter body weight. The objective of this study was to determine the influence of feed supplementation (FS) on post weaning performance of Blackbelly x Pelibuey (Bb x Pb) ewe lambs. Sixteen ewe lambs were used, in a factorial design with two factor and repeated measures on a factor. The factors were the level of FS [low feed supplementation (LFS): 0.26 Mcal ME and 11.7 g CP/lamb/d and increasing feed supplementation (IFS): at beginning as LFS plus increments of 0.13Mcal ME and 5.85 g CP/lamb/d every 40 d] and numer of evaluation period (P). The model included the effects of FS, P and FS x P interaction. The variables studied were BW and ADWG. The FS did not affect (P>0.05) BW and ADWG. However, P and FS x P affected (P<0.05) BW and ADWG. In conclusion, in grazing Bb x Pb ewe lambs the IFS did not improve ADWG with respect to a LFS.

Palabras llave : Hair sheep; post weaning performance; humid tropic; growth.