The effects of gelatin supplementation prior to cooling on ram semen quality and fertility

The physical and chemical characteristics of gelatin have been used to justify its inclusion in extenders to preserve the sperm quality and improve results of cervical artificial insemination with cooled semen. The objective of this study was to evaluate the effects of gelatin supplementation in cooling extender on the quality and fertility of ram semen stored at 5°C. Semen samples (n = 24) of Santa Inês rams (n = 6) were diluted in Glycine-Yolk-Milk extender without (control) or with 1.5% of gelatin. The samples were loaded into 0.25 mL straws, cooled to 5°C and stored vertically for 48 and 72 hours. Sample quality was evaluated using straw homogeneity tests based on pH, osmolality and the proportion of spermatozoa (PS) in both upper and lower segments of straws (US and LS), analyses of sperm motility, plasma and acrosomal membrane integrity, and by fertility after artificial insemination. Differences between the US and LS of straws were found for pH and PS (%). They were significant only in the control group at both times: pH 5.96 vs. 5.71 at 48 h and 6.13 vs. 5.89 at 72 h; PS 21.66 vs. 78.34 at 48 h and 20.87 vs. 79.13 at 72 h. Storage in gelatin had very little, to no effect on the sperm kinetics or on the sperm membrane integrity evaluations. The addition of gelatin to the extender did not affect the pregnancy rate which ranged from 4.4 to 26.1%. We conclude that gelatin is effective in maintaining the physical and chemical homogeneity of the semen samples. Further research is needed in order to optimize the use of gelatin supplementation and elucidate any potential benefits.(AU)

The effects of gelatin supplementation prior to cooling on ram semen quality and fertility

The physical and chemical characteristics of gelatin have been used to justify its inclusion in extenders to preserve the sperm quality and improve results of cervical artificial insemination with cooled semen. The objective of this study was to evaluate the effects of gelatin supplementation in cooling extender on the quality and fertility of ram semen stored at 5°C. Semen samples (n = 24) of Santa Inês rams (n = 6) were diluted in Glycine-Yolk-Milk extender without (control) or with 1.5% of gelatin. The samples were loaded into 0.25 mL straws, cooled to 5°C and stored vertically for 48 and 72 hours. Sample quality was evaluated using straw homogeneity tests based on pH, osmolality and the proportion of spermatozoa (PS) in both upper and lower segments of straws (US and LS), analyses of sperm motility, plasma and acrosomal membrane integrity, and by fertility after artificial insemination. Differences between the US and LS of straws were found for pH and PS (%). They were significant only in the control group at both times: pH – 5.96 vs. 5.71 at 48 h and 6.13 vs. 5.89 at 72 h; PS – 21.66 vs. 78.34 at 48 h and 20.87 vs. 79.13 at 72 h. Storage in gelatin had very little, to no effect on the sperm kinetics or on the sperm membrane integrity evaluations. The addition of gelatin to the extender did not affect the pregnancy rate which ranged from 4.4 to 26.1%. We conclude that gelatin is effective in maintaining the physical and chemical homogeneity of the semen samples. Further research is needed in order to optimize the use of gelatin supplementation and elucidate any potential benefits.

Qualidade seminal de carneiros alimentados com diferentes níveis de energia

A nutrição é um fator que influencia as características reprodutivas, atuando indiretamente na regulação do eixo hipotalâmico-pituitário, ou por uma ação direta no fornecimento de nutrientes para espermatogênese. O objetivo do estudo foi avaliar a influência de diferentes níveis de energia na dieta sobre os aspectos quanti-qualitativos do sêmen de carneiros, esse estudo foi desenvolvido nas dependências do campo experimental Pedro Arle, da Embrapa Tabuleiros Costeiros, situado em Frei Paulo, Sergipe. Vinte e quatro carneiros da raça Santa Inês foram distribuídos aleatoriamente em quatro grupos alimentados com dietas isoproteicas: G3 sem sais de cálcio de ácidos graxos poliinsaturados (SCAGP) e G6, G9, G12 com SCAGP e teores de 3, 6, 9 e 12% extrato etéreo (EE), respectivamente. O sêmen foi coletado nos momentos: 0 (M0), 30 (M30), 60 (M60) e 90 (M90) dias da administração das dietas. O volume seminal, a porcentagem de espermatozóides viáveis e os parâmetros de cinética espermática não diferiram (P>0,05) entre as dietas. Porém, os grupos diferiram (P<0,05) na concentração espermática e no número total de espermatozóides ejaculados. Entre os momentos, o volume do sêmen apresentou aumento (P<0,05) no M90. A partir do M30 foram observados aumento (P<0,05) dos parâmetros MT, RAP e ALH e redução (P<0,05) da concentração espermática. Entre os momentos M30 e M60 houve aumento (P<0,05) na MP, VCL, VSL, VAP, STR e BCF. O aumento do consumo de energia pela suplementação da dieta com SCAGP não tem influencia sobre a quantidade e qualidade dos espermatozóides produzidos por carneiros