title: Reproductive development of male goat kids reared with or without permanent contact with adult females until 10 months of age.
abstract: Adult male ruminants that were reared in contact with females display greater sexual behavior than those reared in single male groups. The aim of the experiment was to compare the reproductive development of prepubertal male kids reared with or without direct permanent contact with adult females until they were 10 months old. Seventeen Saanen male kids were maintained in two groups until 44 weeks of age: kids reared in permanent direct contact with four adult goats (group FEM, N = 8) and kids that remained isolated from females (group ISO, N = 9). All goats in the FEM group became pregnant approximately when bucks attained 28 weeks of age. Scrotal circumference and testosterone concentration were measured, and semen was obtained by electroejaculation to avoid female contact in the ISO group. Scrotal circumference was greater in FEM kids at 12 and 14 weeks of age (P < 0.0001) and testosterone when they were 20 and 22 weeks old (P < 0.0001). Testosterone concentration was greater in ISO kids from 28 to 44 weeks of age. All semen characteristics increased with age (P < 0.0001). Individual motility was greater in FEM kids than that in ISO kids at 15 and 17 weeks (P < 0.005); mass motility was greater in ISO than that in FEM kids at 32 weeks (P < 0.05); total number of spermatozoa/ejaculate was greater in ISO kids at 30, 32, and 40 weeks and in FEM kids at 43 weeks (P < 0.005); total number of motile spermatozoa was greater in ISO kids at 32 and 40 weeks, whereas at 43 weeks, it was greater in FEM kids (P < 0.005). It was concluded that permanent contact with adult goats had transient and short-time positive effects in male kids' reproductive traits during prepubertal development. However, positive effects stopped after goats used as stimulus became pregnant.
authors.affiliation: Departamento de Fisiología, Facultad de Veterinaria, Universidad de la República, Montevideo, Uruguay. Electronic address: lacuesta16@gmail.com.
authors.forename: L
authors.initials: L
authors.lastname: Lacuesta
authors.affiliation: Facultad de Ciencias Agropecuarias, Universidad Autónoma del Estado de Morelos, Cuernavaca, México.
authors.forename: A
authors.initials: A
authors.lastname: Orihuela
authors.affiliation: Departamento de Fisiología, Facultad de Veterinaria, Universidad de la República, Montevideo, Uruguay.
authors.forename: R
authors.initials: R
authors.lastname: Ungerfeld
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D005260:Female; D005298:Fertility; D006041:Goats / Q000097:blood / Q000254:growth & development*; D008297:Male; D011247:Pregnancy; D012661:Semen / Q000502:physiology; D012726:Sexual Behavior, Animal / Q000502:physiology*; D012741:Sexual Maturation / Q000502:physiology*; D013737:Testis / Q000033:anatomy & histology / Q000502:physiology; D013739:Testosterone / Q000097:blood
chemical_list: D013739:Testosterone
keywords: Bucks; Puberty; Sexual development; Sociosexual signal; Testosterone