RESUMO
Background: Artificial insemination and transport of cooled semen has been routinely used in equine industry in the past 20 years. However, more investigations are needed regarding the methods for long time storage in pony stallion semen. The effect of dilution and cooling temperature on pH, sperm motility, membrane integrity and mitochondrial activity were investigated before and after cooling of stallion semen.Materials, Methods & Results: Two ejaculates each from nine Brazilian ponies were diluted in a nonbuffered powder milk extender cooled at 5°C or 15°C for 48 h using three different dilutions (1:1, 1:2 or 1:3). Data were assessed by analysis of variance and the rate comparison was performed using the Duncan test. Samples diluted 1:1 at 5o C or 15°C showed higher pH values (7.63 ± 0.34 e 7.57 ± 0.27) and lower progressive motility (10.3 ± 11.05, 17.08 ± 9.95). All samples cooled at 15°C also showed lower incidence of morphologically altered spermatozoa (1:1 = 55.84%; 1:2 = 51.84%; 1:3 = 49.95%) [P 0.05) despite time and temperature. The pH, progressive motility, mitochondrial activity and membrane integrity remained similar (P > 0.05) on fresh semen samples independent of the dilution grade used. The best results were obtained when semen was diluted 1:3 and cooled at 15°C. All dilution grades were safe for fresh semen and pH wasincreased when semen was diluted and cooled for 48 h.[...]
Assuntos
Análise do Sêmen/veterinária , Diluição , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Temperatura , CavalosRESUMO
Background: Artificial insemination and transport of cooled semen has been routinely used in equine industry in the past 20 years. However, more investigations are needed regarding the methods for long time storage in pony stallion semen. The effect of dilution and cooling temperature on pH, sperm motility, membrane integrity and mitochondrial activity were investigated before and after cooling of stallion semen.Materials, Methods & Results: Two ejaculates each from nine Brazilian ponies were diluted in a nonbuffered powder milk extender cooled at 5°C or 15°C for 48 h using three different dilutions (1:1, 1:2 or 1:3). Data were assessed by analysis of variance and the rate comparison was performed using the Duncan test. Samples diluted 1:1 at 5o C or 15°C showed higher pH values (7.63 ± 0.34 e 7.57 ± 0.27) and lower progressive motility (10.3 ± 11.05, 17.08 ± 9.95). All samples cooled at 15°C also showed lower incidence of morphologically altered spermatozoa (1:1 = 55.84%; 1:2 = 51.84%; 1:3 = 49.95%) [P < 0.01]. Mitochondrial activity was higher on the 1:3 dilution (0.86 ± 0.19 nm) at 5°C and on the 1:1 (0.89 ± 0.23 nm), 1:2 (0.93 ± 0.2 nm) and 1:3 (0.92 ± 0.2 nm) dilutions at 15°C. Progressive motility was higher when semen was diluted 1:3 and cooled at 15°C (42.22 ± 12.38; P < 0.05). Considering mitochondrial activity, similar results were observed when different dilutions of semen were used (P > 0.05) despite time and temperature. The pH, progressive motility, mitochondrial activity and membrane integrity remained similar (P > 0.05) on fresh semen samples independent of the dilution grade used. The best results were obtained when semen was diluted 1:3 and cooled at 15°C. All dilution grades were safe for fresh semen and pH wasincreased when semen was diluted and cooled for 48 h.[...](AU)
Assuntos
Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Temperatura , Diluição , Análise do Sêmen/veterinária , CavalosRESUMO
Background: N-acetyl-L-cysteine (NAC) is a low molecular weight thiol studied as an antioxidant for stallion semen preservation without changes on sperm viability. Equine seminal plasma is rich in sulfur proteins (cysteine residues) named CRISPS, which, when combined with sulfur-containing antioxidants, can enhance the appearance of DNA lesions. The aim of this study was to assess and compare the effect of different concentrations of NAC by evaluating motility, membrane function and sperm chromatin integrity of equine semen cooled at 5C in 50% of seminal plasma. Materials, Methods & Results: Nine ejaculates from 9 stallions were divided into 4 aliquots, diluted and divided in nonsupplemented skim milk group (0.0 mM), or supplemented with 5.0, 2.5 and 0.5 mM NAC. Evaluations were made at 0 h, 24 h and 48 h of cooling, except for motility which was evaluated only up to 24 h. The 0.5 (59.7 M2) and 5.0 mM NAC (55.5 M2) groups showed similar areas of sperm chromatin dispersion among all groups. However, the area of chromatin dispersion between the non-supplemented group was higher = 65.3 M2 than the group supplemented with 2.5 mM. The percentage of cells with a functional plasma membrane was similar between supplemented and non-supplemented (0.0 mM) groups, but higher (P 0.05) in the 0.5 mM NAC (39.7 and 39.8%, respectively) than that of 2.5 mM (34.5%) and 5.0 mM [...](AU)
Assuntos
Animais , Masculino , Sêmen/fisiologia , Cavalos/fisiologia , Cromatina/fisiologia , Motilidade dos Espermatozoides/fisiologia , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Dano ao DNA/fisiologiaRESUMO
Background: N-acetyl-L-cysteine (NAC) is a low molecular weight thiol studied as an antioxidant for stallion semen preservation without changes on sperm viability. Equine seminal plasma is rich in sulfur proteins (cysteine residues) named CRISPS, which, when combined with sulfur-containing antioxidants, can enhance the appearance of DNA lesions. The aim of this study was to assess and compare the effect of different concentrations of NAC by evaluating motility, membrane function and sperm chromatin integrity of equine semen cooled at 5C in 50% of seminal plasma. Materials, Methods & Results: Nine ejaculates from 9 stallions were divided into 4 aliquots, diluted and divided in nonsupplemented skim milk group (0.0 mM), or supplemented with 5.0, 2.5 and 0.5 mM NAC. Evaluations were made at 0 h, 24 h and 48 h of cooling, except for motility which was evaluated only up to 24 h. The 0.5 (59.7 M2) and 5.0 mM NAC (55.5 M2) groups showed similar areas of sperm chromatin dispersion among all groups. However, the area of chromatin dispersion between the non-supplemented group was higher = 65.3 M2 than the group supplemented with 2.5 mM. The percentage of cells with a functional plasma membrane was similar between supplemented and non-supplemented (0.0 mM) groups, but higher (P 0.05) in the 0.5 mM NAC (39.7 and 39.8%, respectively) than that of 2.5 mM (34.5%) and 5.0 mM [...]