Función reproductiva de sementales ovinos importados de Nueva Zelanda durante su primera época reproductiva en México

Veterinaria Mexico (Impact Factor: 0.23). 01/2009;
Source: DOAJ

ABSTRACT La importación de sementales de alto valor genético ha sido una estrategia común en México. Sin embargo, debido a que no se le ha dado seguimiento al desempeño reproductivo de tales sementales se llevó a cabo el presente trabajo para realizarlo en sementales Suffolk durante su primera época reproductiva en México (octubre a febrero). El comportamiento de los valores de la circunferencia escrotal, la cuenta y la morfología espermática, así como las concentraciones circulantes de testosterona de los sementales Suffolk durante su primera época reproductiva en México, coinciden con las que se notifi can en la literatura para esos animales en otras latitudes, aunque en México son de menor magnitud. Los cambios neuroendocrinos-reproductivos derivados de los estímulos ambientales, como las variaciones en la duración de los ciclos luz-oscuridad, han sido ampliamente documentados y se aceptan como responsables de los cambios estacionales en el comportamiento reproductivo de los carneros. En este trabajo, la mayor concentración de testosterona, así como la mayor producción de espermatozoides se observó en diciembre. Estos resultados indican que los sementales Suffolk importados son capaces de mantener su función testicular cíclica, aunque ésta se manifi esta con menor magnitud que en otras latitudes. Se desconocen las causas de este comportamiento, aunque pueden estar relacionadas con los cambios en la duración de los ciclos luz-oscuridad que ocurren en México.

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