الفهرس 
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Abstract
The present study was carried out in the Department of Animal Reproduction and Artificial Insemination, Veterinary Division, National Research Center, Cairo and Department of Physiology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, to investigate the effect of season, maturation medium and maturation time, on IVM of dromedary camel oocytes, in order to improve the subsequent embryonic development.
For this purpose, a total of 320 camel ovaries were collected from
El-Warraq slaughter house at Giza during breeding and non-breeding season (period from August 2010 to May 2012) and transported to the laboratory within 2 hours. In the laboratory, COCs were recovered by aspiration of 2 - 8 mm follicles. A total of 2096 oocytes were collected from 196 ovaries during breeding season and 801 oocytes from 124 ovaries during non-breeding season. Oocytes were aspirated and the number of recovered oocytes was counted per trial and the number of oocytes/ovary was calculated. The recovered COCs were classified according to their morphological criteria into 4 grades; excellent, good, fair and denuded. The good quality recovered oocytes ( excellent and good ) were selected to undergo in vitro maturation and cultured in different maturation medium.
Three separate experiments were performed to investigate the factors affecting IVM of camel oocytes. In experiment1, the effect of seasons of reproduction (breeding and non-breeding seasons) on oocyte yield and quality, and maturation rate were studied. It was found that there is significant increase (p<0.01) in the average number of the oocyte/ovary during breeding season (10.69) than non- breeding season (6.46). The results showed that there is a significant increase (p<0.01) in the excellent and good quality oocyte collected during breeding season than those collected during non-breeding season. Upon studying that there is a significant increase (p<0.01) in the poor quality (fair and denuded) oocyte during non-breeding season than breeding season. There was a significant increase in maturation rate during breeding season in all media when compared with non-breeding season.
In Experiment 2. Studying the effects of four different types of maturation media (CR1aa+ EGF, CR1aa, TCM-199 + EGF and TCM-199) on IVM of camel oocytes was studied. It was found that TCM-199 was superior to CR1aa. When the media was supplemented with Epidermal growth factor (EGF) on in vitro maturation of camel oocytes, the obtained result showed that there was highly significant increase (p<0.01) in the maturation mean ± SE and maturation rate when EGF was added to maturation medium (CR1aa and TCM-199) compared to (CR1aa and TCM-199) without EGF.
In Experiment 3. Studying the effect of maturatoin time on camel oocytes using four medium CR1aa+ EGF, CR1aa, TCM -199 + EGF and TCM-199. During breeding season, there was a highly significant (p<0.01) increase in the maturation mean ± SE and maturation rate (mature oocyte MII) at 40h comparing with 24h maturation time in all maturation media used, in CR1aa+EGF (28.33±0.99, 83% vs 19.60±0.81, 54%), TCM-199+EGF (26.29±0.52, 87% vs 19.60±0.75, 54%) CR1aa (24.83±1.20, 70% vs 15.17±1.08, 43%) and TCM-199 (23.88±0.50, 75% vs 15.67±1.41, 41%).
However, during non-breeding season , the obtained results showed that the maturation mean ± SE and maturation rate showed a highly significant increase when maturation time was 40h comparing with 24h maturation time in all maturation media, in CR1aa+EGF (14.5±0.76, 70% vs 8.5 ± 0.67, 41% P<0.01), TCM-199+EGF (14.00±0.60, 73% vs 8.00 ± 0. 52, 54%, P<0.01), CR1aa (11.25 ± 0.77, 58% vs 5.67 ± 0.61, 28 % p<0.01) and TCM-199 (11.14 ± 0.84, 58% vs 5.50 ± 0.56, 29% p<0.01).