Crecimiento pre y posdestete de corderos Pelibuey en clima cálido húmedo

Abstract: Introduction: In Mexico, there is an unmet demand for sheep meat. To remedy this, it is necessary to study production systems and determine the factors affecting them. The objectives of this study were 1) to evaluate the effect of birth year (BY), type of birth (TB), lambing season (LS), lamb sex (LSX) and parity number (PN) on growth characteristics of pre-and postweaning of Pelibuey lambs and 2) to estimate the relationship among pre and postweaning growth characteristics. Method: The study was retrospective observational with productive data of a sheep farm located in Tabasco, Mexico. The dataset include records from 389 Pelibuey ewes corresponding 941 lambs and 629 lambing. The statistical model included fixed effects of BY (2005 to 2008), TB (single and multiple), LS (dry, rainy and windy), LSX (female and male), PN (primiparous and multiparous), and as well as random effects dam within BY and experimental error. Partial correlation coefficients of Pearson for all response variables were analized. The pre-weaning dependent variables were: weight at birth (BW), average daily gain of adjusted pre-weaning weight to 60 (ADG1) and adjusted weight at weaning to 60 d of age (WWa). Postweaning dependent variables were: average daily gain of adjusted postweaning weight (ADG2) and adjusted final weight to 106 d (FWa). The final weight corresponds to the last weight recorded in productive records, taken at an average age of 165±49 d. Results: With exception of TB and LS on ADG2 and FWa, all independent variables affected (P≤0.05) the preweaning dependent variables. TB and LS affected the preweaning lamb performance (P0.05). The correlation coefficients more high (P 0.05). Los coeficientes de correlación más altos (P<0.01) fueron observados entre Gan1 con Pda y Gan2 con Pfa. Los coeficientes de correlación variaron de 0.27 a 0.88 entre las variables dependientes estudiadas (P