No abstract

To synchronize estrus and ovulation for improving pregnancy rate (PR) of repeat-breeder buffaloes, Controlled Internal Drug Release (CIDR) + prostaglandin (PGF2α) was used before service of repeat breeder buffaloes. Total of 20 cyclic lactating buffalo-cows (4-7 years, 400-500 kg, non-pregnant up to 90postpartum day) and 10 cyclic buffalo-heifers (2.5-4 years, 350-400 kg, not conceived after 3 services) were used in this study. In the 1 st group, a CIDR was inserted for 9 days, regardless reproductive status, and then animals were intramuscularly injected with PGF2α 24 h prior to CIDR removal. In the 2 nd group, control animals were used at the same interval. Animals in heat were naturally served and blood samples were collected on different days post-service for serum P4 determination. Pregnancy was diagnosed on day 25 post-service. Results showed that overall mean of PR was higher (P<0.01), while serum P4 at estrus was lower (P<0.001) in CIDR than in control, but both parameters were not affected significantly by animal type or CIDR x animal type interaction. Serum P4 at estrus was lower (P<0.05) in pregnant than in non-pregnant, regardless treatment or animal type. At the following post-service days, serum P4 showed the same trend of change, being higher (P<0.001) in CIDR than in control animals and in pregnant than in non-pregnant animals, regardless animal type. It could be concluded that the random usage of CIDR device for 9 days and prostaglandin F2α injection 24 h pre-CIDR withdrawal can be applied to improve pregnancy rate of repeat breeder Egyptian buffaloes.

No abstract

Aim of this paper is to find the possibility of in vitro maturation of buffalo oocytes recovered from vitrified whole ovaries. Ovaries from slaughtered buffaloes (n=400) were collected; out of these ovaries, 150 were fresh and 250 buffalo ovaries were vitrified and thawed. Number of all visible follicles was recorded on fresh ovaries and on each ovarian surface pre-and post vitrification, then oocytes recovery rate was calculated in fresh or vitrified ovaries. Oocytes were recovered by aspiration. From the recovered oocytes from fresh ovaries, COCs were vitrified by straw cryodevice. Post-thawing, morphologically normal oocytes from vitrified or fresh ovaries were vitrified. Results showed that numbers of total and normal follicles, and total and normal oocytes per ovary were significantly higher in fresh than in vitrified ovaries. Total number of abnormal follicles showed significantly (P<0.01) an opposite trend, while, the difference in number of abnormal oocytes/ovary was not significant. Oocytes recovered from fresh ovaries showed significantly higher recovery and normality rates than those recovered from vitrified ovaries. Percentage of compact and expanded oocytes was significantly higher, while percentage of denuded and partial denuded oocytes was significantly lower when oocytes were recovered from fresh than from vitrified ovaries. Maturation rate (MIIoocytes percent) was higher (P<0.05) when oocytes were recovered from fresh than from vitrified ovaries and those vitrified after recovery (62.50% vs. 35.90 and 27.50%, respectively). In conclusion, vitrification of the whole buffalo ovaries is a positive tool for genetic sources cryopreservation in term of beneficial effects on in vitro maturation of oocytes when compare with those directly vitrified after recovery from fresh ovaries.

The aims of this study was to evaluate the effect of tonophosphan (TPH), as a phosphorous compound, on resumption of estrus and ovulatory activity of anestrous Egyptian buffalo heifers and anestrous post-partum buffalo cows, in relation with blood phosphorus level. Total of 24 anestrus animals with smooth ovaries and serum progesterone of <1 ng/ml up to 90 days postpartum (12 buffalo cows, weighing 470-530 kg, aging 5-7 years and between 3-4 parities. as well as 12 buffalo heifers, weighing 390-420 kg and 2.5-3 years old) were used in this study. In each of heifer and cow groups (n=12), animals were randomly divided into two subgroups (treated and control, 6 in each). Animals in treatment group (6 heifers and 6 cows) were injected twice at 7 day-interval with 4 ml/100 kg of TPH, while those in control group (6 heifers and 6 cows) were administrated with 4 ml distilled water/100 kg at the same time of TPH treatment. Estrous activity was detected twice daily to detect estrous signs. Blood samples were collected from all animals of each group on days 0, 3, 6, 10, 14, 18, 22, 26, 30, 34 and 38 of treatment. Results revealed that the estrus rate in treated animals was higher (P<0.05) in cows (83.33%) than in heifers (66.67%), while the control animals showed no estrous signs. Intensity, duration and interval from treatment to estrus were nearly similar in both heifers and cows. Concentration of serum P4 was higher (P<0.05) in cows than in heifers only on days 3 and 6 of treatment, while it was higher (P≥0.05) in cows than in heifers on other sampling days. Concentration of P4 was higher (P<0.05) in treated groups than in control on all sampling days, except during the 1 st and six days of treatment. Concentration of P4 was less than 1 ng/ml in control groups on all sampling treatment days, while P4 concentration level was ≥1 ng/ml after 10 days of treatment in treated groups. Concentration of Ca on most sampling days of treatment and P concentration on all sampling days were significantly (P<0.05-P<0.001) higher in heifers than in cows, while Ca:P ratio showed an opposite trend on all sampling days. In conclusion, Based on the foregoing results, twice tonophodphan injection of true anestrous buffalo heifers and cows at a week interval at a level of 4 ml/100 kg LBW has impact on resumption of estrous activity and achieving conception, being more effective for buffalo cows than for buffalo heifers.