Parâmetros reprodutivos em bodes da raça Alpina do nascimento à maturidade sexual

• Ano de defesa: 2012
• Autor(a) principal: Bustamante, Lina Rosa Carazo
• Orientador(a): Guimarães, José Domingos
• Banca de defesa: Torres, Ciro Alexandre Alves
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Medicina Veterinária
• Departamento: Biotecnologia, diagnóstico e controle de doenças; Epidemiologia e controle de qualidade de prod. de
• País: BR
• Palavras-chave em Português: Sêmen; Ecotextura testicular; Biometria testicular
• Palavras-chave em Inglês: Semen; Testicular echotexture; Testicular biometrics
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA
• Link de acesso: http://locus.ufv.br/handle/123456789/5120

The objective of this study was evaluate the quantitative and qualitative parameters of semen and testicular development of Alpine goats during the first 13 months of age, and verify the effect of climate on reproductive characteristics. Four steers with similar age were used were from the first month, raised in Viçosa-MG and managed intensively. Testicular samples were collected weekly between the first and thirteenth month of age. The semen collection was performed twice a week starting at six months of age, when the animals had approximately 25 kg body weight, to assess the seminal characteristics and analysis of plasma membrane integrity by hypo-osmotic swelling test (HOST) for membrane integrity evaluation. The testes were evaluated every two weeks through ultrasound images to assess testicular echotexture. The growth was monitored weekly by measuring the height and body weight. To characterize micro-climate a maximum and minimum thermometer and a dry bulb and wet bulb, was placed in the stalls to determine the temperature and humidity index (THI). The readings were taken once a week at four different times. Body weight and scrotal circumference (SC) showed a linear course (P<0.05), and the latter varied from 9.9±1.2 cm in the first month to 25.7±1.3 cm at thirteenth months, and the changes of greater magnitude were between the first and fifth months. The length, width and testicular volume increased progressively until the eighth month to become unstable for the next ones. Similar behavior was observed in testicular echotexture, which was largest in the eighth month, indicating that in this age structuring and stabilization of the testicular parenchyma occurred, and the changes in testicular measurements may be due to the increased length of the seminiferous tubules and changes in the photoperiod region. The beginning of the seminal evaluations at six months of age showed that the animals were in transition between teenage and sexual maturity, reaching sexual maturity at nine months of age. The HOST was an important tool to evaluate the integrity of goat sperm plasma membrane. The animals have not heated to thermic stress as seen by the THI index and the reproductive characteristics were not influenced by seasonal variations of the environment parameters. The testicular ultrasonography was an effective exam, capable of detecting changes in testicular parenchyma over time and as a alternative tool to differentiate normal and pathological conditions in goats.