Time filter

Source Type

Khalili B.,Jafar Abad Livestock Central Research Institute | Jafaroghli M.,University of Payam e Noor | Farshad A.,University of Kurdistan | Paresh-Khiavi M.,Jafar Abad Livestock Central Research Institute
Asian-Australasian Journal of Animal Sciences | Year: 2010

Two experiments were designed to evaluate the effects of the amino acids glycine and cysteine on cryopreservation of ram spermatozoa. After primary evaluation of collected ejaculates, the semen samples were pooled and diluted 1:4 before cooling (experiment 1) and freezing (experiment 2) with Tris-Citrate-Fructose-Yolk (TCFY) extender supplemented with different concentrations of glycine and cysteine (5, 10, 15 and 20 mM). As the control, semen was diluted and frozen in the extender without amino acids. Motility, viability and membrane integrity were assessed as the parameters for semen quality in the first experiment. In the second experiment, motility, progressive motility, viability, membranes and acrosome integrity were evaluated after the freezing-thawing process. The results of the first experiment indicated that the addition of 10 and 15 mM cysteine compared to the control (basic) extender significantly increased (p<0.01) the motility, viability and membrane integrity of spermatozoa after cooling. However, further increasing these amino acids up to 20 mM had a significant negative effect (p<0.05). Our results showed no significant differences (p>0.05) between 5 mM glycine compared to 5 mM cysteine and between 20 mM glycine and 20 mM cysteine. The results of experiment 2 showed that the amino acids significantly improved post-thaw motility, progressive motility, viability, membranes and acrosome integrity of ram spermatozoa. These positive effects were observed at concentrations between 5 to 15 mM of glycine and cysteine, with the best results at 15 mM. Further increasing of amino acid concentrations significantly decreased the post-thaw characteristics of spermatozoa, but the results showed that cysteine was better than glycine and control extenders. The data indicated that addition of glycine or cysteine to the freezing extender can be recommended for cryopreservation of ram spermatozoa. However, further studies are still needed to determine the effect of such addition on fertility in farm animals.

Jafaroghli M.,Payame Noor University | Khalili B.,Jafar Abad Livestock Central Research Institute | Farshad A.,University of Kurdistan | Zamiri M.J.,Shiraz University
Small Ruminant Research | Year: 2011

This study was conducted to elucidate the effect of increasing the osmolality of a basic Tris, extender supplemented with sucrose, trehalose or raffinose on post-thawing ram semen quality (sperm motility, viability, acrosome integrity, total sperm abnormalities and membrane integrity). After primary evaluation of the collected ejaculates, only semen samples with more than 70% motile sperm, and a sperm concentration of higher than 3×109sperm/ml were used for cryopreservation. The semen samples were pooled and diluted (1:4) with a Tris-citric acid-fructose-yolk extender, supplemented with different concentrations (50, 70 or 100mM) of sucrose, trehalose or raffinose. As control, semen was diluted and frozen in the base diluent, without additional sugars. Pooled semen samples were aspirated into 0.25ml straws, cooled to 5°C within 90min and frozen by exposure to liquid nitrogen vapor (4-5cm above the liquid nitrogen surface) for 10min - before plunging into liquid nitrogen, for storage. After 24h, straws were thawed in a water bath (37°C) for 30s. The frozen-thawed sperm characteristics were improved significantly (P<0.05) by increasing the level of the sugars. Optimal results being obtained with 70 and 100mM trehalose or raffinose. All extenders containing supplemental sugars were superior in terms of sperm quality to the control (P<0.01) group. The highest sperm motility (60.6±1.9%), viability (60.6±2.5%) and membrane integrity (58.2±2.1%) were recorded using 100mM trehalose and the lowest with 50mM sucrose (48.6±1.9%, 51.4±2.5% and 47.9±2.1%, respectively). All sugar concentrations decreased the percentage of acrosomal and total sperm abnormalities (P<0.05). The extenders containing 100mM trehalose or raffinose significantly (P<0.05) decreased the occurrence of sperm abnormalities, compared to the other treatments. The fertility rates obtained after cervical insemination of the frozen-thawed sperm were 46.8%, 44.1% and 16.7% for 100mM trehalose, 100mM raffinose and the control with supplementation of the diluents, respectively. The study showed that ram sperm can tolerate hyperosmotic diluents, and that a range of sugar concentrations (50-100mM) may successfully be incorporated in the ram semen cryopreservation diluents, although further research is warranted. © 2010 Elsevier B.V.

Zamiri M.J.,Shiraz University | Khalili B.,Jafar Abad Livestock Central Research Institute | Jafaroghli M.,Payame Noor University | Farshad A.,University of Kurdistan
Small Ruminant Research | Year: 2010

The aim of the present study was to monitor seasonal variations in semen characteristics, testicular size, and plasma testosterone concentration in Iranian Moghani rams. An artificial vagina was used to collect semen from 10 rams (3-4 years of age), from November (autumn) 2008, to October (autumn) 2009. Testicular circumference was larger (P<0.05) during late summer (September) to early autumn (November). Ejaculate volume, sperm density, progressive motility and the percentage normal sperm on the other hand were higher (P<0.05) during autumn and lowest during winter (P<0.05). The plasma testosterone concentration was higher during autumn (P<0.05) than at any other time of the year, while the testicular circumference was positively correlated with the testosterone concentration, percentage live/normal sperm and semen concentration. The lowest level of lactate dehydrogenase (LDH) in the seminal fluid was recorded during early October (autumn) (1.52U/mL) and the highest level in early spring (2.57U/mL). The lowest levels of K+ and Na+ in the seminal fluid were recorded in spring (72.7 and 70.2mg/dL, respectively). However, the variation of the highest levels was in late autumn (94.1 and 72.4mg/dL, respectively), with the variation in the Na+ concentration being much smaller than that of K+. The correlation coefficient of the percentage live/normal sperm and sperm motility with seminal fluid K+ level (r=0.61 and 0.49, respectively) and Na+ level (r=0.48 and 0.34, respectively) were positive, with the LDH correlation being negative (r=-0.51 and -0.43, respectively) (P<0.01). In spite of monthly variations in sperm quality and testicular measurements, the semen quality of the Moghani rams was within the range regarded as satisfactory for normal fertility. It would seem as if the best quality semen for long-term preservation of Moghani sperm is produced during autumn. © 2010 Elsevier B.V.

Jafaroghli M.,Payame Noor University | Abdi-Benemar H.,University of Mohaghegh | Zamiri M.J.,Shiraz University | Khalili B.,Jafar Abad Livestock Central Research Institute | And 2 more authors.
Animal Reproduction Science | Year: 2014

Sixteen fertile rams were randomly allotted to four groups and fed either of the four diets for 14 weeks: (1) control diet (COD) without fish oil (FO) and vitamin C (VC), (2) diet containing 2.5% FO (FOD), (3) diet containing 300. mg/kg DM VC (VCD), and (4) diet containing 2.5% FO and 300. mg/kg DM VC (FCD). Semen was collected at 14-d intervals from 1 April to 10 July (out of the physiologic breeding season in Iran). Semen volume and percentages of motile and progressively motile sperm were increased by FO and VC feeding. A significant interaction was also found between FOD and VCD on motility and progressive motility percentage (P< 0.05). HOS-test and percentage of sperm with normal acrosome improved significantly by FO and VC. Rams fed FCD had better HOS-test and higher proportion of sperm with normal acrosome than rams in other groups (82.4 and 93.6%, respectively). Diets containing FO and FO and VC increased the proportion of docosahexaenoic acid in sperm (P< 0.05). The activity of lactate dehydrogenase in the seminal fluid was significantly affected by VC and the interaction between FO and VC (P< 0.05). Blood metabolites, except glucose, were affected positively by FO. The results showed that dietary supplementation with FO and VC improved seminal quality and may have beneficial effects on fertility in Moghani rams. © 2014 Elsevier B.V.

Farshad A.,University of Kurdistan | Yousefi A.,Islamic Azad University at Saveh | Moghaddam A.,Razi University | Khalili B.,Jafar Abad Livestock Central Research Institute
Asian-Australasian Journal of Animal Sciences | Year: 2012

This experiment was conducted to study variations of serum testosterone and seminal characteristics of Markhoz male goats. Blood samples were obtained via jugular vein, and semen was collected by using an artificial vagina from 14 fertile male goats (23 years of age), at 15-day intervals starting on 15 July and ending on 30 October 2010 (during breeding and non-breeding season). Semen volume, total sperm (voiume×concentration), live sperm (%), abnormal sperm (%) and semen pH were significantly superior during the late summer and early autumn (breeding season). Variation of sperm density, motility and progressive motility was not significant during the sampling period. The results presented show that the lowest and highest levels of lactate dehydrogenase in the seminal plasma were recorded in late October (2.82 U/ml) and in late August (4.81 U/ml), respectively. Moreover, the study indicated that the serum testosterone concentration was higher during late summer and early autumn (p<0.05) than at any other of sampling period. There were negative correlations between volume and sperm density (-0.135, p<0.05), and positive correlations between volume and percentage live sperm (0.224) and percentage progressive motility (0.194, p<0.01). Sperm density was correlated with live sperm (0.200, p<0.05) and progressive motility (0.202, p<0.01). The correlation between live sperm and progressive motility was 0.554 (p<0.01). Furthermore, the results in this study indicated a significant positive correlation between live sperm and LDH (0.450) and a negative correlation between sperm density and LDH concentration (-0.272) (p<0.01). Significant, but positive correlations were found between sperm motility and LDH (0.542) and testosterone concentration (0.522), respectively (p<0.05). In conclusion, this study demonstrated that the best obtained semen was collected in late summer (during decreasing photoperiod) and early autumn (September and October). This also coincides with the natural breeding season of Markhoz goats in Iran.

Discover hidden collaborations