Efecto de la suplementación alimenticia con fuentes lipídicas sobre la ganancia de peso y niveles de testosterona sérica en toros bufalinos

ABSTRACT
The aim of the study was to evaluate the effects of dietary supplements based on copra meal or palm kernel cake on body weight, scrotal circumference and testosterone levels of buffalo bulls kept in intensive rotational grazing. Fifteen buffaloes (457.8±98.3 kg and 3.2±1.3 years) grazing areas of Panicum maximum vr. Mombaza received daily supplementation (1% of body weight) in individual feeders. Animals were randomly assigned to three treatments: Control (n = 5; conventional concentrate based on ground corn and soy-bran), T1 (n = 5; concentrate based on copra meal) and T2 (n = 5; concentrate based on palm kernel cake). The experiment was conducted during 252 days, divided in nine periods of 28 days (P1 to P9). The feed intake was monitored daily, the body weight and scrotal circumference every 28 days (P1 to P9) and plasma testosterone levels every 14 days (P7 to P9). The average weight gain varied from 0.92 to 0.97 kg/animal/day. The average body weight and scrotal circumference did not differ between treatments (P>0.05). Animals in T2 had higher average levels of testosterone (2.2 ng/mL) compared to Control (1.8 ng/mL) and T1 (1.6 ng/mL) (P<0.05). Positive correlations were observed between body weight and testosterone levels (r = 0.58; P<0.0001) and between testosterone and scrotal circumference (r = 0.16; P<0.02). In conclusion, the new dietary supplements promoted performance similar to the conventional concentrate, considering the body weight gain and the testicular biometry in young buffalo bulls. However, the use of palm kernel cake was more efficient in raising serum testosterone levels. [...]