Influência das proteínas do plasma seminal sobre a qualidade do sêmen ovino congelado

• Autor(a) principal: Goularte, Karina Lemos
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFPel - Guaiaca
• Texto Completo: http://repositorio.ufpel.edu.br/handle/ri/2530
• topic: Proteínas; Plasma seminal; Sêmen congelado; Ovinos; Proteins; Seminal plasma; Frozen semen; Ram; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA

The expansion of artificial insemination (AI) programs with frozen ram semen has been limited by the need of intrauterine semen deposition and by the inconsistency of the association between the conventional methods used to evaluate semen quality and in vivo fertility. An alternative to improve the efficiency of AI programs would be the profiling of the protein content of the seminal plasma to search for fertility markers. The objective of the present study was to study the protein profile of ram seminal plasma and to evaluate its association with parameters of frozen semen quality. Ejaculates were split in two samples. The first sample was frozen in two extenders: T1 (Tris + egg yolk + glycerol); and T2 (Tris + egg yolk + threalose). The second sample was submitted to unidimensional electrophoresis to identify proteins in the seminal plasma. The presence of the identified proteins was associated with parameters of semen quality: sperm motility and membrane integrity, both prefreezing and post-thawing, and post-thawing acrosome integrity. Post-thawing sperm motility did not differ (P > 0.05) for T1 (18.6 ± 2.3) and T2 (23.4 ± 2.7). Post-thawing sperm membrane integrity was similar (P > 0.05) for T1 (12.6 ± 1.4) and T2 (15.3 ± 1.7). There was also no difference (P > 0.05) between T1 and T2 with regard to postthawing acrosome integrity (23.0 ± 1.5 e 21.3 ± 1.8, respectively). An intra-ram analysis identified 17 proteins associated with the evaluated parameters: 10 of them presented similar associations for distinct rams. In the inter-ram analysis, an 11 kDa band was associated with lower pre-freezing sperm membrane integrity, a 24 kDa band was related to reduced post-thawing sperm motility and membrane integrity, and a 45 kDa band was associated with lower pre-freezing sperm membrane integrity (P < 0.05). Thus, those three protein factors would be potential markers for ram infertility with frozen semen because their absence was associated with improved semen quality, regardless of individual ram effects.