Reza Ijab; Esmail Ayen; Amir Khaki; Ali Soleimanzadeh
Volume 13, Issue 1 , March 2022, , Pages 61-70
Abstract
Heat stress (HS) has caused relative hypoxia, oxidative stress and high level of homocysteine, which contributes significantly to fertility failures in bulls. The aim of present study was to evaluate the role of dietary betaine (BET) in improving dual purpose Simmental (Fleckvieh) post-thawed semen quality ...
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Heat stress (HS) has caused relative hypoxia, oxidative stress and high level of homocysteine, which contributes significantly to fertility failures in bulls. The aim of present study was to evaluate the role of dietary betaine (BET) in improving dual purpose Simmental (Fleckvieh) post-thawed semen quality especially during the hottest summer days. A total number of 16 mature bulls were randomly assigned to three equal groups including: 1) Control condition (without betaine), 2) BET1: 57.00 mg of betaine kg-1 per day and 3) BET2: 114 mg of betaine kg-1 per day, through daily intakes for 90 days in summer. Plasma levels of homocysteine, seminal plasma antioxidants levels and sperm parameters such as DNA fragmentation, chromatin integrity, motility, viability, morphology and membrane integrity were evaluated. Under maximal HS, serum homocysteine concentrations were reached 16.67 ± 0.09 µmol L-1. Dietary betaine supplementation influenced DNA fragmentation of sperm and was higher in the control group compared to BET2 group. There were significant decreases in seminal plasma superoxide dismutase (SOD), glutathione peroxidase (GPx) activity and sperm viability and motility in bulls treated with betaine. The activity of GPx and SOD in the control group was increased up to 0.08 ± 0.00 U mg-1 protein and 0.52 ± 0.01 U mg-1 protein in seminal plasma. There were no significant differences between groups in the percentage of swollen spermatozoa, membrane integrity, sperm morphology, abnormal head morphology and percentage of spermatozoa stained with aniline blue. In conclusion, BET supplements improved semen parameters in sperm motility, sperm viability and influenced DNA fragmentation during HS with reduction in serum homocysteine concentrations.
Theriogenology
Amir Khaki; Atefeh Araghia; Mehdi Lotfi; Alireza Nourian
Volume 10, Issue 4 , December 2019, , Pages 333-341
Abstract
Artificial insemination is a well-established and widely used method for genetic improvement in cattle breeding industry. Recently, researchers have shown an increased interest in the cryoprotective effects of minerals and antioxidants on semen. Previous studies on calcium (Ca) and magnesium (Mg), two ...
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Artificial insemination is a well-established and widely used method for genetic improvement in cattle breeding industry. Recently, researchers have shown an increased interest in the cryoprotective effects of minerals and antioxidants on semen. Previous studies on calcium (Ca) and magnesium (Mg), two main macro-minerals, have mainly investigated their roles in mammalian spermatogenesis and fertility. In addition, the experimental data examining the semen content regarding these minerals and antioxidants from different animal species are rather controversial and there is no general agreement about their associations with semen quality. Therefore, this study was conducted to assess the seminal plasma concentrations of Ca, Mg and total antioxidant capacity (TAC) in first and second ejaculations of dual-purpose Fleckvieh bulls and to link them to the sperm characteristics of fresh and frozen-thawed semen. Sperm progressive motility after thawing was used to classify the data into three groups: < 40.00%, 40.00 to 50.00% and > 50.00%. The measurements of two minerals and TAC were carried out using spectrophotometry and enzyme-linked immunosorbent assays, respectively. The results showed that there were significant differences in several parameters of semen quality between first and second ejaculations. No significant differences were also found on Ca and Mg concentrations and Ca/Mg ratio. The TAC level was significantly higher in the first ejaculation than the second one. The findings of this study suggest that TAC is a potential marker for bull semen quality assessment in the frozen semen production industry.
Sadegh Mayahi; Morteza Mamouei; Saleh Tabatabaei; Khalil Mirzadeh
Volume 5, Issue 3 , July 2014, , Pages 201-205
Abstract
High ambient temperature is the major constraint on Buffalo productivity. The aim of this study was to evaluate the reproductive performance and thyroid gland function in winter and summer seasons in Khuzestan buffalo bulls. Six male indigenous buffaloes of Khuzestan with nearly the same age (2-3 years ...
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High ambient temperature is the major constraint on Buffalo productivity. The aim of this study was to evaluate the reproductive performance and thyroid gland function in winter and summer seasons in Khuzestan buffalo bulls. Six male indigenous buffaloes of Khuzestan with nearly the same age (2-3 years old) and weight were used. Semen and blood samples through jugular vein were collected, every two weeks throughout the summer and winter seasons. The thyroid hormones and thyrotropin stimulating hormone (TSH) concentration in blood serum were measured by radioimmunoassay method. Semen quality was determined, using computer assisted sperm analyzer (CASA) and routine methods. The concentration of thyroxin (T4) was lower in winter than summer (p ≤ 0.05). The level of T3 uptake was higher in cold season than that of in hot season (p ≤ 0.05). The differences of tri-iodotyronine (T3) and TSH concentrations, as well as free thyroxin index were not significant between seasons. The semen volume and spermatozoa parameters including concentration, progressive motility, linear velocity, mean velocity, beat cross frequency, linear coefficient and straightness coefficient were higher in winter than summer (p ≤ 0.05). Semen pH and amplitude of lateral head displacement of spermatozoa were higher in summer than winter (p ≤ 0.05). In winter, there was positive correlation between spermatozoa concentration and T3 value of blood serum (p ≤ 0.05). There were positive correlations between values of semen volume and T4, progressive spermatozoa motility percent and TSH, as well as, total motility of spermatozoa and TSH in summer (p ≤ 0.05). In general, thyroid function and semen quality of Khuzestan buffaloes may be affected by seasons.
Reza Asadpour; Razi Jafari; Hossein Tayefi-Nasrabadi
Volume 2, Issue 4 , December 2011, , Pages 218-221
Abstract
The objective of this study was to evaluate effect of different concentrations of catalase in two extenders on motility, viability and lipid peroxidation bull spermatozoa during semen freezing process. Thirty ejaculates collected from ten Holstein bulls were pooled and evaluated at 37 °C. Pool ejaculated ...
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The objective of this study was to evaluate effect of different concentrations of catalase in two extenders on motility, viability and lipid peroxidation bull spermatozoa during semen freezing process. Thirty ejaculates collected from ten Holstein bulls were pooled and evaluated at 37 °C. Pool ejaculated was split into two main experimental groups, 1 and 2. In experiment 1, specimen was diluted to a final concentration of 30 × 106 spermatozoa with citrate-egg yolk and in experiment 2; specimen was diluted with tris-egg yolk extender to the same concentration. In both experiments diluted semen was divided into three aliquots, including a control and two test groups. Each aliquot was rediluted with an equal volume of extender either without (control) or with one of the antioxidants contained one of the following antioxidants: catalase (CAT; 100 IU mL-1) catalase (CAT; 200 IU mL-1) and control group. No significant differences were observed in sperm viability and motility following addition of catalase enzyme at concentration of 100 IU mL-1 and 200 IU mL-1 to citrate-egg yolk extender. But the highest sperm viability was achieved by addition of 100 IU mL-1 and 200 IU mL-1 catalase to tris-egg yolk semen extender compared with the control group (P < 0.05). Malondialdehyde levels did not change with addition of catalase in both extenders compared with the control group. The obtained results provide a new approach to the cryopreservation of bull semen, and could positively contribute to intensive cattle production.
