Effects of reduced glutathione and catalase on the kinematics and membrane functionality of sperm during liquid storage of ram semen

AbstractThe objective of this study was to evaluate the effects of reduced glutathione (GSH) and catalase (CAT) supplementation on the kinematics and membrane functionality of sperm during the liquid storage of ram semen, cooled at 5°C, for up to 24h. Semen samples from four rams were pooled, diluted with Tris-egg yolk extender without antioxidants (control) or supplemented with either CAT (100, 200, and 400U/mL) or GSH (100, 200, and 400mM) at a final concentration of 50×106sperm/mL. Sperm kinematics, which was analyzed by computer-assisted sperm analysis (CASA), and membrane functionality, which was analyzed using the hypo-osmotic swelling test (HOST), were determined after the addition of the semen samples at different processing times (fresh/diluted, 1.5, 6, 12, and 24h, at 5°C). No significant differences were recorded in the kinematics or membrane functionality between treatments at different times. The supplementation of diluents with 100 and 200U/mL of CAT prevented the harmful effects of cooling on total sperm motility. No significant differences were observed in progressive sperm motility throughout processing, regardless of the treatment and time of evaluation. Supplementation with 400mM GSH resulted in an earlier reduction (P<0.05) of total sperm motility, a decrease in rapid sperm rate and a reduction in curvilinear velocity during incubation, at 5°C. The cooling induced a reduction (P<0.05) in the percentage of sperm with a functional plasma membrane (HOST), especially after 1.5h of incubation. Based on the results of the present study, the addition of CAT (100 and 200U/mL) reduced the deleterious effects of cooling on total motility in ram sperm maintained at 5°C for 24h, although it did not affect the functionality of the sperm membranes. However, the addition of 400mM GSH caused negative effects on the velocity parameters of the sperm

Desempenho produtivo de tambacus alimentados com dietas suplementadas com vitamina E

O objetivo deste trabalho foi avaliar os efeitos da suplementação da dieta de tambacus com concentrações de vitamina E sobre variáveis de desempenho e hematológicas, bem como determinar a relação da atividade da glutationa peroxidase com a inclusão de vitamina E e selênio na dieta. Foram utilizados 250 juvenis de tambacu, divididos em 25 aquários. A dieta basal constituiu-se de ração peletizada com 32% de proteína bruta e 3.300 kcal kg-1 de energia digestível, e inclusão de 0,40 mg kg-1 de Se. As dietas-teste - isoprotéicas e isoenergéticas - foram compostas da dieta basal com diferentes concentrações de vitamina E (0, 100, 200, 300, 400 mg kg-1), em delineamento inteiramente ao acaso, com cinco tratamentos e cinco repetições. Não foi observado efeito significativo da suplementação com vitamina E sobre o comprimento total, volume corpuscular médio, concentração de hemoglobina corpuscular média e número de eritrócitos, nem sobre a atividade da glutationa peroxidase. Peso final e conversão alimentar aparente, no entanto, sofreram efeito dos tratamentos suplementados. O teor de 400 mg kg-1 de vitamina E melhorou o comprimento padrão e ganho de peso. A suplementação da dieta com vitamina E resulta em melhor desempenho produtivo de tambacus