Time filter

Source Type

Tuncer P.B.,Livestock Central Research Institute | Tasdemir U.,General Director of Food and Control | Buyukleblebici S.,Aksaray Technical science Vocational School | Ozgurtas T.,Gulhane Military Medical Academy | And 4 more authors.
Small Ruminant Research | Year: 2013

Few studies have been done on the effects of trehalose supplementation in the cryopreservation of Angora buck semen. The objective of present study was to investigate the effects of the addition of trehalose at different doses in semen extenders, on in vitro semen quality parameters, anti-oxidant enzymes activities and DNA damage after the freeze-thaw process in Angora buck semen. Semen samples from 5 mature Angora bucks (3 and 4 years of age) were used in this study. The bucks, belonging to the Livestock Central Research Institute were maintained under uniform breeding condition. A total number of 40 ejaculates were collected twice a week from the bucks using an artificial vagina, during the breeding season and the semen pooled to minimize individual variation. Each pooled ejaculate was split into 7 equal aliquots and diluted (37. °C) with base extenders supplemented with the trehalose (12.5, 25, 50, 75, 100 and 150. mM), and a base extender with no additives (control). Diluted samples were aspirated into 0.25. ml French straws, and equilibrated at 5. °C for 4. h and then were frozen at a digital freezing machine. The freezing extender supplemented with 50. mM trehalose led to the greatest percentages of CASA motility (53.6. ± 4.69), in comparison to the other groups after the freeze-thawing process (P < 0.05). The addition of different doses of trehalose did not provide any significant effect on the percentages of post-thaw sperm motion characteristics (VAP, VSL and LIN), compared to the control (P > 0.05). The freezing extender with 150. mM trehalose group led to the highest percentages of acrosome abnormalities (P < 0.05) and 50. mM trehalose group had the lowest percentages of total abnormalities (P < 0.001), in comparison to the others. There were no significance differences in the DNA integrity among treatment groups (P > 0.05). The different doses of trehalose did not show any effectiveness on the maintenance GPx, LPO, GSH, CAT and total antioxidant activities, when compared to the control (P > 0.05). Therefore, the additions of 50. mM and 75. mM doses of trehalose will be useful in increasing post thaw motility on Angora buck semen. © 2013 Elsevier B.V. Source

Tasdemir U.,Livestock Central Research Institute | Buyukleblebici S.,Aksaray University | Tuncer P.B.,Livestock Central Research Institute | Coskun E.,Gazi University | And 4 more authors.
Cryobiology | Year: 2013

The objectives of this study was to compare the effects of type and concentration of cryoprotectants glycerol (G), ethylene glycol (EG) and dimethyl sulfoxide (DMSO) on the plasma membrane and DNA integrity as well as antioxidant activity of cryopreserved Eastern Anatolian red bull sperm. Ejaculates were collected from the three bulls using an artificial vagina twice a week. The ejaculates were pooled to increase the semen volume for replication and to eliminate variability among the evaluated samples. The pooled ejaculates were also split into seven equal experimental groups and diluted with the modified base extender to a final spermatozoa concentration of 15×106/ml. The extended samples were cooled slowly to 4°C and equilibrated for 4h. They were then loaded into 0.25ml French straws and frozen using a digital freezing machine at 3 programmed rates: -3°C/min from +4°C to -10°C, -40°C/min from -10°C to -100°C, and -20°C/min from -100°C to -140°C. Thereafter, the straws were plunged into liquid nitrogen at -196°C. Frozen straws were thawed individually at 37°C for 30s in a water bath to analyse progressive motility and sperm motion characteristics as well as membrane integrity using hypo-osmotic swelling test. Biochemical assays were performed in a spectrophotometer using commercial kits. DNA damage was evaluated by Comet Assay using Image Analysis System. 6% G exhibited the greatest percentages of CASA (43.7±2.92%) and progressive (26.4±2.64%) motilities when compared to the other groups (P<0.001). 6% G and 6% EG showed the greatest values of preserved membrane integrity (P<0.001). 6% DMSO and 3% EG + 3% DMSO resulted in greater chromatin damage than the other groups (P<0.001). The antioxidant activities of GPx, GSH, and CAT as well as the total antioxidant activity were affected by the type of cryoprotectant; notably, 2% G+2% EG+2% DMSO yielded the lowest activities when compared to the other groups (P<0.001).In conclusion, no advantages were found in using EG or DMSO to replace G in bull sperm cryopreservation. Freezing with cryoprotectant 6% G yielded the best post-thaw sperm characteristics for Eastern Anatolian Red bull spermatozoa. © 2012 Elsevier Inc. Source

Discover hidden collaborations