Body Composition and Cold Resistance of the Neonatal Pig from European (Large White) and Chinese (Meishan) Breeds

Abstract

Body composition, plasma parameters and cold resistance were compared in neonatal pigs from Chinese (Meishan, Ms) and European (Large White, Lw) breeds. Newborn Ms pigs weighed less but had a higher (p less than 0.05) percentage of body dry matter and protein than the Lw pigs, whereas both breeds had similar levels of body fat and liver and muscle glycogen. Plasma concentrations of fructose and alpha-fetoprotein were lower (p less than 0.05) in the newborn Ms pigs. Cold resistance test performed in a 6-7 degrees C environment on the same piglets when aged 2 and 24 h, showed that in both breeds, cold resistance was closely dependent upon body weight and significantly improved (p less than 0.01) with age. Despite their 16% lower body weight, Ms piglets were, at both ages studied, as resistant to cold as the Lw ones. Breed had no effect on pretest concentration of plasma glucose and noradrenaline, but pretest concentrations of plasma free fatty acids (FFA) were higher (p less than 0.01) in the Ms than in Lw piglets and those of adrenaline were lower (p less than 0.01) in the Ms Lw piglets and those of adrenaline were lower (p less than 0.01) in the Ms piglets. Breed had no significant effect on the response of plasma glucose, FFA and catecholamines during exposure to cold. At both ages of exposure, plasma concentrations of glucose and catecholamines were significantly increased. Plasma concentrations of FFA were increased (p less than 0.01) at 2 h, but at 24 h a decrease (p less than 0.01) was observed during cold exposure. Colostrum from Ms sows had greater concentration of lipids than that from Lw sows. It is suggested that the similar resistance to cold of the Ms and Lw piglets despite the lower body weight of the former is due, in part, to a greater availability of FFA as an energy source.