HISTOLOGIC CHARACTERIZATION OF TESTICULAR DEVELOPMENT IN Columba livia (AVES:COLUMBIFORMES)

OLEA, GB.; SANDOVAL, MT.; HERNANDO, AB.; LOMBARDO, DM.

Tandil

Jornada; Primeras Jornadas de Ciencias Morfológicas de las Sierras de Tandil. Universidad del Centro de la Provincia de Buenos Aires (UNCPBA).; 2011

Universidad del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias.

In the birds, the gonads are organized and differentiate to dividing a couple of genital combs, which are constituted by Cells Germinate Primordial (CGPs), of origin extra-gonadal. In this stage they are "indifferent" and it is not possible to differentiate the sexes. Later in the masculine gonad the túbulos seminíferos are organized differentiating the sexual cells from the CGPs. Studies of the development gonadal in birds have been studied in species model as Gallus gallus domesticus. Some authors propose that in this taxon doesn’t exist a state of "indifferent" since the sites of colonization of the CGPs differ between males and females. From these two models, the study of the development gonadal in different species of  birds will help to elucidate variations in the patterns of development gonadal in vertebrates. In this work we describe the histogénesis in Columba livia´s testicles.We analyzed the histological constitution of testicles of embryos from the stage (E.) 21 to 44. And neonatos of 4, 13 and 25 days post-hatching (dpe). We realized prepared histological following the tecnic of coloration with hematoxilina-eosina, tricrómica of Masson and PAS. The histological analysis showed that from E. 21 to 24 the gonad is formed by a loose tissue of cells of support and CGPs distributed uniformly. In E. 27 organize the medullary cords which form the túbulos seminíferos since E.37. At the end of the development the testicle presents túbulos seminíferos clump, formed for espermatogonias and Sertoli´s cells, surrounded by Leydig´s cells. In the neonatos between 13 and 25 dpe the above mentioned constitution is kept and inside the túbulos seminíferos a light is demonstrated. These results allow to infer an initial condition of "undifferentiation" in the development gonadal and contribute information for comparative studies with other species of birds.   Keywords: ontogeny, primordial germ cells, medullary cords.