Efeito da adição da L-carnitina e acetil-L-carnitina sobre a viabilidade espermática na refrigeração do sêmen equino

• Ano de defesa: 2014
• Autor(a) principal: Lisboa, Fernando Paixão [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Equino - Sêmen; Semen - Metabolismo; Carnitina; Preservação do sêmen; Antioxidantes; Cryopreservation
• Link de acesso: http://hdl.handle.net/11449/113913

Over the years, technology for cooling semen has developed. However, despite progress, pregnancy rates are still variable between reproductive programs.Carnitine is a vitamin compound which plays an important role in energy metabolism, since it guarantees the sperm energy production by stimulating metabolic pathways. Furthermore, carnitine has a powerful antioxidant effect, providing greater protection to plasma membrane during storage.However, post-ejaculation use is poorly studied, being none in horses. The aim of experiment 1 was determine optimal concentration of lcarnitine (LC) and acetyl-l-carnitine (AC) in equine semen cooled at 5°C. In experiment 2, the objective was evaluate dose effects between LC, AC and their association on sperm viability by flow citometry. Two ejaculates from 12 stallions were used in both experiments. After dilution with Botu-Semen®to 50 x 106 spermatozoa/ml, each ejaculate was split into seven groups: control (C), treated with 5 mmol/L (LC-1), 10 mmol/L (LC -2), 15 mmol/L (LC-3) of LC, treated with 5 mmol /L (AC-1), 10 mmol/L (AC-2) and 15 mmol/L (AC-3) of ACand then cooled at 5°C for 48 hours. In second experiment, groups were divided in: control (C), treated with 10 mmol /l of LC (LC), treated with 10 mmol /L of AC (AC) and 10 mmol/L of LC + 10 mmol/L of AC (LC+AC).In both experiments,sperm kinetics was evaluated by computerized analysis (CASA) and plasma membrane integrity (IMP) by epifluorescence microscopy.Moreover, in experiment 2 were assessed DNA, ROS and Lipid Peroxidation (PEROX) by flow cytometry.All analysis were performed before cooling (T0), 24 (T24) and 48 hours (T48) after. According to the results of first experiment, LC groups had higher IMP and better values of kinetic than control. Groups treated with AC showed higher results of sperm kinetics after 24 hours of refrigeration and IMP in all analysed times. In second experiment, treated groups were ...