INFLUENCE OF A PHOTO-STIMULATION ON OVARY AND EMBRYO RECOVERY IN NULLIPAROUS RABBIT FEMALES Export

@inproceedings{citeulike:5262890, abstract = {The goal of the present experiment was to estimate the effect of a photo-stimulation following previous one month maintenance of the young rabbits within short-day (8L:16D) conditions and applied during 10 days before artificial insemination (AI). Forty 17-weeks old nulliparous rabbit does were divided into four experimental groups (10 does/group). Group L was kept in constant long-day (16L:8D) photoperiod until insemination, imitating commercial situation. Groups S+4, S+6 and S+8 were first submitted to a short photoperiod (8L:16D) then the duration of the light was increased with 4, 6 and 8 hours, respectively, 10 days before insemination. AI was performed with standard techniques using fresh heterospermic pools. Doe rabbits were sacrificed at 48 hours after AI. Ovarian function was evaluated, oviducts were flushed to collect embryos and evaluate them after 48 hours in in vivo conditions. Increasing daylight hours did not influence receptivity, as assessed by the vulva state at the moment of insemination, nor weight of the two ovaries and average ovary length. Only one doe did not ovulate in group S+4. The mean number of corpora lutea in ovulated females was 13.2, 5.7, 10.6, 12.0 in groups L, S+4, S+6, S+8, respectively (P<0.001). Proportion of embryo donor does was different (P<0.10) being 1.0 the highest value in the group S+6 and 0.71 the lowest in the group S+4. The highest number of collected embryos for inseminated does was in group S+6 with 9.2 and the lowest in S+4 with 3.4 per doe (P<0.001). Embryo recovery rate was the highest (0.89) in S+6 group and this was significantly (P<0.001) different from the results of the other groups (0.56, 0.64 and 0.52, respectively for S+4, S+8 and L). Proportion of 96 hours old good quality embryos within the total washed amount was the highest in group L and S+8 (0.84 and 0.87, respectively) and lower in S+4 and S+6 (0.69 and 0.71, P<0.05). Ovarian follicle anomalies (follicle cysts and haemorrhagic follicles) were present in each group: the average value (1.4 per inseminated doe) was the lowest in group S+8 and was more than 3 times higher in group L (4.7 per inseminated doe, P<0.001). Higher proportion of the receptive females gave an embryo and the embryo recovery rate was also higher in these does compared to the non-receptive females. It is concluded that switching light hours from 8 to 14 per day leads to the same proportion of the embryo donor does, embryo recovery rate, number of collected embryos and similar number of blastocysts appropriate for transfer per inseminated female in comparison with the constant long day illumination. Smaller change of daylight hours is probably insufficient. Long days either by 8 hours supplemental lighting or constant however can result in lower embryo recovery rate.}, author = {Virag Gy and G\'{o}cza, E. and Hiripi, L. and B\H{o}sze Zs}, booktitle = {9th World Rabbit Congress – June 10-13, 2008 – Verona – Italy}, citeulike-article-id = {5262890}, citeulike-linkout-0 = {http://world-rabbit-science.com/WRSA-Proceedings/Congress-2008-Verona/Papers/R-Virag.pdf}, day = {10}, keywords = {embryo, ovary, photo-stimulation, rabbit}, month = {June}, pages = {471--476}, posted-at = {2009-07-25 17:41:48}, priority = {0}, title = {INFLUENCE OF A PHOTO-STIMULATION ON OVARY AND EMBRYO RECOVERY IN NULLIPAROUS RABBIT FEMALES}, url = {http://world-rabbit-science.com/WRSA-Proceedings/Congress-2008-Verona/Papers/R-Virag.pdf}, year = {2008} }

TY - CONF ID - citeulike:5262890 L3 - citeulike-article-id:5262890 N2 - The goal of the present experiment was to estimate the effect of a photo-stimulation following previous one month maintenance of the young rabbits within short-day (8L:16D) conditions and applied during 10 days before artificial insemination (AI). Forty 17-weeks old nulliparous rabbit does were divided into four experimental groups (10 does/group). Group L was kept in constant long-day (16L:8D) photoperiod until insemination, imitating commercial situation. Groups S+4, S+6 and S+8 were first submitted to a short photoperiod (8L:16D) then the duration of the light was increased with 4, 6 and 8 hours, respectively, 10 days before insemination. AI was performed with standard techniques using fresh heterospermic pools. Doe rabbits were sacrificed at 48 hours after AI. Ovarian function was evaluated, oviducts were flushed to collect embryos and evaluate them after 48 hours in in vivo conditions. Increasing daylight hours did not influence receptivity, as assessed by the vulva state at the moment of insemination, nor weight of the two ovaries and average ovary length. Only one doe did not ovulate in group S+4. The mean number of corpora lutea in ovulated females was 13.2, 5.7, 10.6, 12.0 in groups L, S+4, S+6, S+8, respectively (P<0.001). Proportion of embryo donor does was different (P<0.10) being 1.0 the highest value in the group S+6 and 0.71 the lowest in the group S+4. The highest number of collected embryos for inseminated does was in group S+6 with 9.2 and the lowest in S+4 with 3.4 per doe (P<0.001). Embryo recovery rate was the highest (0.89) in S+6 group and this was significantly (P<0.001) different from the results of the other groups (0.56, 0.64 and 0.52, respectively for S+4, S+8 and L). Proportion of 96 hours old good quality embryos within the total washed amount was the highest in group L and S+8 (0.84 and 0.87, respectively) and lower in S+4 and S+6 (0.69 and 0.71, P<0.05). Ovarian follicle anomalies (follicle cysts and haemorrhagic follicles) were present in each group: the average value (1.4 per inseminated doe) was the lowest in group S+8 and was more than 3 times higher in group L (4.7 per inseminated doe, P<0.001). Higher proportion of the receptive females gave an embryo and the embryo recovery rate was also higher in these does compared to the non-receptive females. It is concluded that switching light hours from 8 to 14 per day leads to the same proportion of the embryo donor does, embryo recovery rate, number of collected embryos and similar number of blastocysts appropriate for transfer per inseminated female in comparison with the constant long day illumination. Smaller change of daylight hours is probably insufficient. Long days either by 8 hours supplemental lighting or constant however can result in lower embryo recovery rate. EP - 476 TI - INFLUENCE OF A PHOTO-STIMULATION ON OVARY AND EMBRYO RECOVERY IN NULLIPAROUS RABBIT FEMALES T2 - 9th World Rabbit Congress – June 10-13, 2008 – Verona – Italy SP - 471 KW - embryo KW - ovary KW - photo-stimulation KW - rabbit AU - Virag Gy AU - Gócza, E AU - Hiripi, L AU - Bősze Zs PY - 2008/06/10/ UR - http://world-rabbit-science.com/WRSA-Proceedings/Congress-2008-Verona/Papers/R-Virag.pdf ER -