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Corderos Pelibuey (n = 14) nacidos de siete madres con reproducción estacional (E) o de otras siete continuas (C) fueron mantenidos en condiciones intensivas con la finalidad de determinar si existen diferencias en algunos eventos asociados a la pubertad. Los corderos, nacidos en noviembre, fueron pesados cada 15 días, y una vez destetados a los 60 días fueron revisados semanalmente para registrar el momento del completo desprendimiento de adherencias prepuciales (DAP) y el grado de desarrollo de la circunferencia escrotal (CE). Al observarse el DAP, los corderos fueron sometidos semanalmente a electro-eyaculación (7,5 volts). No existieron diferencias (P > 0,05) entre los dos grupos en la edad al DAP (92,29 ± 27,63 vs 95,43 ± 15,69 días para corderos E y C, respectivamente), y en el peso corporal al DAP (24,43 ± 2,98 vs 24,14 ± 1,93 kg) y la CE (17,14 ± 2,17 vs 18,14 ± 1,44 cm) a esta edad. La CE se correlacionó con el DAP (r = 0,59, P = 0,026) y el peso corporal en este momento (r = 0,69, P = 0,007). Por otro lado, los corderos de ambos grupos tampoco mostraron diferencias (P > 0,05) en el momento en que alcanzaron la pubertad, referida como el momento en que se obtuvo un eyaculado con al menos 50 × 10^6 espermatozoides/mL y al menos 50% de motilidad (144,07 ± 8,43 días), el peso corporal (32,60 ± 3,94 kg) la CE (25,86 ± 2,24 cm) y el porcentaje de anormalidades espermáticas (18,33 ± 15,57%). La edad a la pubertad se correlacionó con la CE (r = 0,59, P = 0,027). Los resultados sugieren que los mecanismos fisiológicos que provocan la aparición de la pubertad en corderos Pelibuey son independientes del patrón de reproducción de sus madres. Male Pelibuey lambs (n 14) born from seven ewes with seasonal breeding (S) or seven non-seasonal ewes with continuous oestrus activity (C) were maintained under intensive management conditions to determine if there were any differences between them in events associated with puberty. All lambs, born in November, were weighted every 15 days and as soon as they were weaned (60 days of age), they were examined every week to record complete prepucial release (CPR) and to assess the development of the scrotal circumference (SC). As soon as CPR was observed, the lambs were submitted to electroejaculation (7.5 volts) once a week. There was no statistical difference between groups in the CPR (92.29 ± 27.63 vs 95.43 ± 15.69 days for S and C, respectively), body weight (BW; 24.43 ± 2.98 vs 24.14 ± 1.93 kg) or SC (17.14 ± 2.17 vs 18.14 ± 1.44 cm) at that age. SC was a significantly correlated (P = 0.026) with CPR (r 0.59) and highly correlated (P = 0.007) with BW (r 0.69). There were also no differences (P > 0.05) in age at puberty, considerate as the age when an ejaculate had at least 50 × 10^6 sperms/mL and 50% motility (144.07 ± 8.43 days), BW (32.60 ± 3.94 kg), SC (25.86 ± 2.24 cm) and the percentage of sperm cells abnormalities (18.33 ± 15.57%). Age at puberty was significantly correlated (P = 0.027) with SC (r = 0.59). The results suggested that the physiological mechanisms that induce puberty in the male Pelibuey lambs are independent of the reproduction pattern of their mothers. 437 - 442 Bimestral |
