Abstract: A 2x2 factorial arrangement was used for evaluating performance traits during 16 weeks in 2 groups of 22 Yorkshire x Landrace (YL) and 13 Pelón Mexicano (PM) castrate male and female pigs 63 days old which were allotted at random into 2 rearing systems consisting of total (15 and 7 pigs) or partial confinement (7 and 6 pigs). Partial confinement included rearing animals outdoors in a grass prairie (Brachiaria brizantha) from 9:00-16:00 h. No significant differences (p<0.05) for the interaction rearing system x genotype were found in any measured performance trait. It was observed that treatments involving Yorkshire x Landrace animals had a high significant (p<0.001) live weight at any age, as compared to the PM pigs. It was evident that YL pigs had a higher daily feed intake than PM animals and on the other hand, results from animals in confinement clearly indicated that feed intake in those pigs was higher than in the others, permitted to graze during 8 h every day. Calculated daily gain was 820 and 757 g in YL pigs when reared in total confinement or partially outdoors, whereas this same trait was 414 and 335 g in PM pigs. When a comparison was made between improved and local pigs reared in total confinement, feed conversion was on average, 3.07 kg kg-1 in the YL animals and 5.03 kg kg-1 in the PM pigs.
M. Becerril , C. Lemus , J.G. Herrera , M. Huerta , M. Alonso-Spilsbury , R. Ramirez-Necoechea , D. Mota-Rojas and J. Ly , 2009. Studies on Growth of Pelon Mexicano Pigs: Effect of Rearing Conditions on Performance Traits. Journal of Animal and Veterinary Advances, 8: 208-212.