A total of 1,243 records for 585 dairy Friesian cows from 1997–2004 were used to study the factors affecting dystocia and its effects on reproductive performance and milk production. The overall incidence of dystocia was 6.9%. The percentage of dystocia decreased with increasing live body weight, age, and parity of cows (P < 0.05); however, it increased with increasing birth weight of calves (P < 0.05). The highest percentage of dystocia was detected in winter season, but the least percentage was in summer season (P < 0.05). The percentage of incidence of dystocia was significantly (P < 0.05) higher with winter feeding compared to summer ration (8.2% vs. 5.1%). The percentage of incidence of dystocia was significantly (P < 0.05) higher with twinning than single calving (15.5% vs. 6.5%), while not significantly affected by the sex of born calves. Incidence of dystocia had adverse effects on reproductive performance and milk yield. The service interval, service period, days open, and calving interval were significantly (P < 0.05) longer in cows afflicted with dystocia compared to normal cows. The conception rate was lower (P < 0.05), but the number of service per conception was higher (P < 0.05) in cows afflicted with dystocia compared to normal cows (60.5% vs. 73.0% and 3.4 vs. 2.7, respectively). Average daily milk yield was lower (P < 0.05) by 1 kg for cows with incidence of dystocia compared to normal cows.

Application of assisted reproductive technology in camelidea, such as artificial insemination (AI) and embryo transfer, has been slow in comparison to that for other livestock species. In Egypt, there are few attempts to establish in vitro maturation (IVM) and fertilization (IVF) techniques in dromedary camel. The present study was carried out to produce Sudanese camel embryos using in vitro matured oocytes and epididymal spermatozoa. Dromedary camel ovaries were collected from abattoirs and then, the oocytes were aspirated from all the visible follicles on the ovarian surface (~2-8 mm in a diameter). Meanwhile, Fetal Dromedary Camel Serum (FDCS) was obtained from camel fetuses after slaughtering. Thereafter, only Cumulus Oocyte Complexes (COCs) were matured in vitro in the Tissue Culture Medium (TCM-199) complemented with 10% FDCS. Spermatozoa required for in vitro fertilization were collected from testes (epididymal cauda) of the slaughtered camel bulls. The results clearly showed that the maturation rate of oocytes at metaphase II was about 59.5% while the fertilization rate was around 70.4%. Intriguingly, the embryo rates determined were 13.1%, in 2-cell; 0.0%, in 4-cell; 34.7%, in 8-16% cell; 39.1%, in morula and 13.1% in a blastocyst stage. This study represented a successful in vitro production of Sudanese dromedary camel embryos from epididymal sperm cells and in vitro matured oocytes recovered from slaughtered camels.

The aim of this work was to study the effect of oral administration of whole extract from Moringa oleifera (MO) at levels of 0, 60 and 120 mg/head for 21 days on performance and semen characteristics of rabbit bucks. Total of 12 adult New Zealand rabbit bucks having live body weight (LBW) of 2304-2750 g/h kg and at six menthe of age were divided into three similar groups (n = 4 in each). Bucks in the 1 st group were given 3 ml sterile distilled water (Control, G1), while those in the 2 nd and 3 rd groups were given 3 ml distilled water containing 60 (G2) or 120 (G3) mg from the whole extract of MO. Bucks in all groups were treated as daily oral administration for 21 days before semen collection. All bucks were fed commercial complete feed diet and kept under the same managerial and climatic conditions. Semen was collected twice a week for 8 weeks. On day of semen collection, reaction time (RT) was calculated and semen was evaluated for volume (SV), pH value, mass (MM) and progressive (PM) motility, sperm livability (SL) and abnormality (SA) percentages, sperm cell concentration (SCC), total sperm output/ejaculate (TSOP), damaged acrosome (DA) and response to osmotic test at osmolaity level of 50 mOsm/l for 30 min at 37 o C (curled spermatozoa, CS). The obtained results revealed insignificant effect of MO on LBW of bucks. RT and percentages of MM, PM, SL, SA, SCC, TSO, DA and CS were improved (P<0.05) by MO at both levels. Semen pH value did not differ in G2 or G3 from that in G1, but pH value was higher (P<0.05) in G3 than in G2. SV increased (P<0.05) by about 27% only in G3 as compared to the G1, but did not differ from that in G2. RT and all physical semen characteristics were affected (P<0.05) by collection week, except semen pH value and DA percentage, which showed insignificantly inconsistent trend of changes throughout the collection period. RT and SA decreased (P<0.05), while SV, MM, PM, SCC and TSO increased (P<0.05) by advancing collection week. SV and CS showed inconsistent (P<0.05) trend of change during the collection weeks. The effect of interaction between treatment and collection week was not significant on RT and all semen characteristics studied. Rabbit does mated by bucks in G2 showed the best results reproductive performance, in terms of the highest kindling rate, total number of borns, total and live litter size at birth and viability rate at weaning, but the differences were not significant. Also, does mated by bucks in G2 showed the highest (P<0.05) proportion of females, litter size at weaning, and litter weight at birth and weaning. Rabbit does mated by bucks in G3 showed the highest (P<0.05) average bunny weight at birth. In conclusion, moringa oleifera extract at a level of 60 mg/h as oral administration for 21 days has significant value in improving the antioxidant status and could serve as a supportive treatment in the nutritional management to improve semen production of rabbit bucks, and consequently increasing reproductive performance of rabbit does mated by this semen.

Total of 24 rabbit does (5-7 mo of age, 3-4 kg LBW and 1-2 parities were used to study the effect of superovulation by PMSG on ovarian characteristics, quality and measurements of embryos at different stages (pronucli, morula and blastocyst) of Baladi Red (BR) rabbit does. Also, 3 fertile BR bucks were used for natural mating. All does and bucks were kept under the same conditions of feeding and management. Does in the 1 st group (n=12) were injected with 20 mg GnRH/doe (0.2 ml Receptal) immediately after natural mating (control, G1), while does in the 2 nd group (n=12) were superovulated by injection of 40 IU/kg LBW from PMSG (Foligon), followed by 0. 2 ml receptal immediately after natural mating (treatment, G2). Does in G1 and G2 were sub-divided into 3 sub-groups, 4 does in each. Ovarian characteristics were determined and embryos were recovered by flushing from each treated doe in each sub-group slaughtered after 40-46 h of mating for collection of embryos at pronucli stage (1-16 cell embryos), after 60-64 h of mating for embryo collection at morula stage and after 70-72 h of mating for those at blastocyst stage. Embryos were recovered from each uterine horn and oviduct per doe by flushing and morphologically measured for thickness of mucin coat (MC), zona pellucida (ZP) and interzonal (IZ), as well as total diameter of embryos (TDE) with or without MC at different stages. Results show that average ovarian weight (right and left) and ovarian weight relative to LBW were higher (P<0.05) in G2 than in G1 (0.26 and 0.22; 0.15 vs. 0.33 and 0.27 g/doe; 0.19 g/kg LBW, respectively). Ovulatory response in terms of average number of normal follicles (large and small), hemorrhagic follicles and total follicles and average number of corpora lutea (CLs) were greater (P<0.05) in G2 than in G1

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The aim of this study was to evaluate the effect of different periods of ovary preservation at 25-30 °C for 5, 6, 7, 9, 12 and 24 h on recovery rate and oocyte categories of dromedary camel oocytes. Camel ovaries were collected from El-Bassatein slaughterhouse, Cairo. The collected ovaries were placed immediately after slaughtering into thermos in saline solution (0.9% NaCl) supplemented with antibiotics (100 IU penicillin and 100 μg streptomycin/ml) at 25-30 °C and transported to the laboratory within 4-5 h. Ovaries were washed three times with warmed (30 °C) phosphate buffer solution (PBS) and one time with ethanol (70%). All visible follicles on the ovarian surface (2-8 mm in diameter) were counted. Oocytes were aspirated using a 20-gauge hypodermic needle. Oocyte yield was recorded and the number of oocytes/ovary was calculated. Oocytes were classified into five categories (compact, partial denuded, denuded, shrunken and cleaved oocytes). Results show that average number of follicles on each ovary was not significantly affected by preservation period, although tended to reduce only after 5 h of ovary preservation. However, this number was insignificantly reduced by increasing period of ovary preservation more than 5 up to 24 h. Average number of oocytes on each ovary was significantly (P < 0.05) reduced only between 5 and 6 h of ovary preservation. Average number of oocytes showed higher reduction rate between 5 and 6 h from 12.4 to 9.3/ovary as well as between 9 and 12 h. Oocyte recovery rate showed insignificant decrease from 88.1% at 5 h to 78.6% at 9 h of preservation. However, it showed significant (P < 0.05) reduction to 62.0% between 9 and 12 h, then insignificantly decreased to 58.6 at 24 h of preservation of the ovaries. Frequency distribution and recovery rate of each category was the highest for compact oocytes and the lowest for cleaved oocytes at all periods of preservation. Increasing preservation period significantly (P < 0.05) decreased frequency distribution of compact and cleaved oocytes, while increased frequency distribution of partial denuded, denude and shrunken oocytes. It might be concluded from the present results that the preservation of dromedary camel ovaries at 25-30 °C for 5-6 h was effective for maintaining the oocytes quality and recovery rate compared with the other preservation periods.

The aim of this study was to evaluate the effect of cryopreservation by conventional straws on viability and normality, in vitro maturation and fertilization and blastocyst production rate of cryopreserved immature buffalo oocytes. Oocytes were recovered from ovaries of slaughtered buffaloes, cryopreserved in tissue culture medium and thawed. Thereafter, oocytes were in vitro matured, fertilized and cultured. The obtained results indicated that viability rate (89.2 vs. 92.7%) and normality percentage (67.7 vs. 80.3%) was lower (P<0.05) for the cryopreserved than fresh oocytes. Percentage of oocytes at stage (in vitro maturation rate) was lower (P<0.05) for cryopreserved than fresh oocytes (40.8 vs. 61.7%). Fertilization rate was lower (P<0.05) for cryopreserved than fresh oocytes (38.5 vs. 75.3%). Blastocyst rate relative to total oocytes was lower (P<0.05) for cryopreserved than fresh oocytes (5.2 vs. 23.6%). This study indicated the possibility of cryopreserved immature buffalo oocytes collected from ovaries of slaughtered buffaloes to in vitro mature, fertilize and develop to embryos at blastocyst stage, but at a little extend of that in fresh case.

Conventional semen analysis are not sufficient to evaluate bull's fertility, however it might be used as a preliminary evaluation for predicting fertility potential. Sperm DNA integrity may give a better evaluation of bull fertility potential. In the current study, six mature buffalo bulls were divided into two groups (based on a threshold of 70% motility; as high or low potential fertility). The first objective of the current study was to evaluate DNA fragmentation (measured as Comet value) in the two groups of bulls (three bulls/group) in relation to its potential fertility. The results showed that low potential fertility bulls had significantly (P<0.05) more sperm DNA damage, higher (P<0.05) sperm abnormal morphology and lower (P<0.05) sperm viability than that of sperm from the high potential fertility bulls. Our second objective was to assess whether a relationship exists between bull's sperm DNA damage and bull in vitro fertility. A significant variations (P<0.05) in the developmental competence of the embryos to the morula and blastocyst stages were observed. The results also showed a clear negative correlation between bull's potential fertility and DNA integrity at and the ability of the fertilized ova to sustain its development to the morula (r=-0.756) and blastocyst stage (r=-0.643). These results indicate that measuring DNA integrity could be a powerful marker of bull's fertility. Therefore, screening bulls for DNA damage should be emphasized along with routine semen analysis in selecting bulls either for natural mating or artificial insemination.