Reproduction Abstracts

The study of the sperm is particularly relevant to reproduction of the species and can promote morphological information necessary for reproduction biotechnologies. The agouti is a rodent found in the South America and represents an excellent source of animal protein. In captivity, the establishment of pubescent occurs at 9 months of age. The aim of this study is to describe the ultrastructure of sperm during sexual development of agoutis kept in captivity. The testes of animals were collected by orchiectomy and weighed. Subsequently, the testes were fixed by immersion in a solution of 2.5% glutaraldehyde for 24 h. Segments of the testis of agouti males at different stages of sexual development (prepubertal, pubescent, and adult) were performed by transmission electron microscopy. During prepubertal stage occurs the formation of pre-acrosome vesicle and headline, in addition to organization of centrioles. Mitochondria migrate to the opposite pole of the cell and arrange themselves to form the flagellum. From the pubescent stage, the spermatozoa are already fully formed: head, neck, body, and tail. This study was the first about ultrastructure of the sperm in the agouti. The sperm is not fully formed during prepubertal stage. During the pubescent stage the sperm is characterized by a tapered head without distinction as of acrosome, unlike other wild species like the cavy, guinea pig, and armadillo.