The effect of three levels of inclusion of cotton seed meal (PA) of low level of gossypol in the concentrate of 36 replacement Holstein calves was evaluated. Three treatments were used: T0: 0% PA; T1: 10% PA and T2: 20% PA with 0, 150 and 300 ppm of free gossypol respectively. The diets were supplied from birth to weaning (60 days). No significant differences were observed between treatments for feed consumption, body weight gain, final body weight or size. On the contrary, the activity of the serum sorbitol dehydrogenase enzyme was 29.5, 44.7 and 59.5 U/l for T0, T1 and T2, respectively (p<0.001), exceeding the value considered normal (14.7 ± 1.3 U/l); however, there were no visible negative effects on calves.

Se evaluó el efecto de tres niveles de inclusión de pasta de algodón (PA) de nivel bajo de gosipol en el concentrado de 36 terneras Holstein de reemplazo, Se trabajó con tres tratamientos: T0: 0% PA; T1: 10% PA y T2: 20% PA con 0, 150 y 300 ppm de gosipol libre, respectivamente. Las dietas fueron suministradas dese el nacimiento hasta el destete (60 días). No se observaron diferencias significativas entre tratamientos para consumo de alimento, ganancia de peso, peso vivo final ni altura a la cruz. Por el contrario, la actividad de la enzima sorbitol deshidrogenasa sérica fue de 29.5, 44.7 y 59.5 U/l para T0, T1 y T2, respectivamente (p<0.001), superando el valor considerado como normal (14.7 ± 1.3 U/l); no obstante, no hubo efectos negativos visibles en las terneras.

The aim of this study was to determine the differences between three class intervals obtained from the levels of blood urea nitrogen (BUN) and the pregnancy rate in alpacas during the reproductive season. The study was conducted in a community cooperative in Cerro de Pasco, Peru at an altitude of 4318 m in February 2017. Fifty-two adult alpacas with more than two parturitions were evaluated. Blood samples were taken on the day of the single mount. BUN levels were determined using a commercial colorimetry kit and pregnancy was determined by ultrasonography 35 days post- mounting. The BUN levels varied between 15.07 and 46.88 mg/dl and the pregnancy rate was 59.6%. The pregnancy rate was associated with lower and higher levels of blood urea nitrogen.

The aim of this study was to know the levels of phosphorus and its effects on feed intake and body weight in female alpacas during the breeding season (January-February) and weaning (August-September). In the first phase, serum phosphorus levels were determined in 200 11-13-month-old alpacas, located in four alpaca regions of Peru. P levels were 8.25 ± 1.63, 5.25 ± 1.46, 6.42 ± 1.84 and 4.8 ± 1.61 mg/dl for the regions of Pasco, Junín, Cuzco and Puno, respectively, with significant differences (p<0.05) between regions. P values in one region were below the reference limit (5-11.5 mg/dl) and the another near the lower limit, which could be considered as deficient in P. In the second phase, a controlled experiment was carried out with three concentrations of P in the diet: 0.16% (T1), 0.25% (T2) and 0.34% (T3), using 16 weaned female alpacas per group (7-8 months, 25.25 ± 1.62 kg)...

El objetivo del estudio fue determinar las diferencias entre tres intervalos de clase obtenidos a partir de los niveles de nitrógeno ureico sanguíneo (NUS) y la tasa de preñez en alpacas durante la estación reproductiva. El estudio se realizó en una cooperativa comunal de Cerro de Pasco, Perú a una altitud de 4318 msnm en febrero de 2017. Se evaluaron 52 alpacas adultas con más de dos partos. Las muestras de sangre se tomaron en el día de la monta única. Los niveles de NUS se determinaron mediante un kit comercial por colorimetría y la preñez fue determinada mediante ultrasonografía a los 35 días de la monta. Los niveles de NUS variaron entre 15.07 y 46.88 mg/dl y la tasa de preñez fue de 59.6%. La tasa de preñez estuvo asociada a los niveles más bajos y más altos de nitrógeno ureico sanguíneo.

The aim of this study was to know the levels of phosphorus and its effects on feed intake and body weight in female alpacas during the breeding season (January-February) and weaning (August-September). In the first phase, serum phosphorus levels were determined in 200 11-13-month-old alpacas, located in four alpaca regions of Peru. P levels were 8.25 ± 1.63, 5.25 ± 1.46, 6.42 ± 1.84 and 4.8 ± 1.61 mg/dl for the regions of Pasco, Junín, Cuzco and Puno, respectively, with significant differences (p<0.05) between regions. P values in one region were below the reference limit (5-11.5 mg/dl) and the another near the lower limit, which could be considered as deficient in P. In the second phase, a controlled experiment was carried out with three concentrations of P in the diet: 0.16% (T1), 0.25% (T2) and 0.34% (T3), using 16 weaned female alpacas per group (7-8 months, 25.25 ± 1.62 kg)...