The effect of testosterone on penis-prepucial adherences and production of fibre was studied in 30 alpacas. Animals were 18 months old and were distributed in three groups: without treatment (T0), treated with testosterone enanthate (0.5 mg/kg/body weight) every two weeks during 12 weeks (T2E), and castrated (C0). The penis-prepucial adherences, testicular size, sexual behavior and body weight were evaluated every two weeks, and fibre samples were collected at the beginning of the study and at the end of three experimental periods. In a 4-week pre-experimental phase all parameters were evaluated for adjusting the data of the experimental phase. Release of penis-prepucial adherences was greater in T2E than in T0 and C0 between weeks 8 (p<0.001) and week 12 (0.006>p<0.001). Higher testicular size (length, width, and thickness) occurred in T0 than in T2E between weeks 4 and 12 (0.0...

Se evaluó el efecto de la testosterona sobre las adherencias pene-prepuciales y producción de fibra. Se usaron 30 alpacas de 18 meses de edad, distribuidas al azar en tres grupos: machos sin tratamiento (T0), machos tratados con enantato de testosterona (0.5 mg/kg/peso vivo) cada dos semanas durante 12 semanas (T2E), y machos castrados (C0). Las adherencias pene-prepuciales, tamaño testicular, comportamiento sexual y peso corporal se evaluaron cada dos semanas, y muestras de fibra se recolectaron al inicio delestudio y al final de tres periodos experimentales. Se tuvo una fase pre-experimental de cuatro semanas donde se evaluaron los parámetros en estudio para ajustar los datos de la fase experimental. La liberación de las adherencias pene-prepuciales fue mayor en T2E que en T0 y C0 entre la semana 8 (p<0.001) y la semana 12 (0.006>p<0.001). El incremento testicular (largo,...