الكلمات المفتاحية
GPG
Dairy Cows
How to Cite
الملخص
This research aims to study the effect of hormonal treatment on the postpartum period, by using a hormonal program called GPG. In this study, 30 heads of dairy cows were used, which had given birth at least once their ages ranged between (3-5) years, which gave birth at least 80 days ago, without any reproductive disorders (normal uterus-normal ovaries). The cows were randomly divided into three groups. The First, group (G1)(n=10): was treated with GPG program (GnRH 50 mcg in day (0) - PGF2α 150 mcg in day (7) - GnRH 50 mcg in day (9) im) then an artificial insemination was performed 16 hours after the end of the hormonal treatment, regardless of estrus signs. The second group (G2) (n=10): was treated as in the first group, but was artificially inseminated twice (16 and 24 hours after the end of the hormonal treatment). third group (G3)(Control)(n=10): were treated with a physiological solution at the same time intervals as the three injections used in the experimental groups, and then an artificial insemination was performed 12 hours after the appearance of estrus signs Ultrasound scan was performed on day 35 after AI in all inseminated cows to diagnose pregnancy. The results showed that there was a significant difference (P≤0.05) between (G1-G2) groups and the control group (G3) regarding the rates of estrus emergence, while no significant difference was observed between (G1and G2) groups immediately after the treatment. The results also showed a significant difference (P≤0.05) between (G1-G2-G3) groups regarding pregnancy rates, as the highest pregnancy rate was recorded in the (G2) group immediately after the treatment and also cumulatively. The results also showed that Insemination index in the two experimental groups (G1-G2) reached (1.4-1.28),respectively, as this number was considered to be a good fertility indicator. It was concluded from this study the importance of administration of GPG program to improve and to increase pregnancy rates in cows during anestrus period due to repeated insemination after the end of hormonal treatment as observed in the second group.
References
2. Alnimer, M.A., Tabbaa, M. J., Ababneh, M.M., and Lubbadeh, W.F. (2009(. Applying variations of the Ovsynch protocol at the middle of the estrus cycle on reproductive performance of lactating dairy cows during summer and winter.Theriogenology;72:731-740.
3. Bhoraniya, H.L., Arjunbhai, J., Dhami, Naikoo, M., Bhupendra, C., Parmar, Nareshbhai, P., and Sarvaiya. (2012). Effect of estrus synchronization protocols on plasma progesterone profile and fertility in postpartum anestrous Kankrej cows. Trop Anim Health Prod 44:1191–1197.
4. Burke, J.H., De La Sota, R.L., Risco, C.A., Staples, C.R., Schmitt, E. J.P., and Thatcher, W W. (1996). Evaluation of timed insemination using a gonadtotropin-releasing hormone agonist in lactating dairy cows. J. Dairy Sci.,79:1385-1393.
5. Crowe, M., Padmanabhan, V., Mihm, M., Beitins, Z., and Roche, F. (1998). Resumption of follicular waves in beef cows is not associated with periparturient changes in follicle-stimulating hormone heterogeneity despite major changes in steroid and luteinizing hormone concentrations. Biol Reprod;58:1445-1450.
6. Dalton, J.C., Nadir, S., Bame, J.H., Noftsinger, M., Nebel, R.L., and Saacke, R.G. (2001). Effect of Time of Insemination on Number of Accessory Sperm,Fertilization Rate, and Embryo Quality in Nonlactating Dairy Cattle. Journal of Dairy Science Vol. 84, No. 11.
7. De Rensis F., Bottarelli E., Battioni F., Capelli T., Techakumphu M., García -Ispierto I., López-Gatius F. (2008). Reproductive performance of dairy cows with ovarian cysts after synchronizing ovulation using GnRH or hCG during the warm or cool period of the year. Theriogenology, 69, 481–484.
8. Divakar, J., and Ambrose. (2015). Postpartum Anestrus and its Management in Dairy Cattle. Bovine Reproduction, Chapter 52;p:457-470.
9. Geary, T.W., Whittier, J.C., Hallford, D.M., and MacNeil, M.D. (2001). Calf removal improves conception rates to the Ovsynch and CO-Synch protocols. Journal of Animal Science, 79(1), 1-4.
10. Ginther, O., Kot, K., Kulick, L., Martin, S., and Wiltbank, M. (1996). Relationships between FSH and ovarian follicular waves during the last six months of pregnancy in cattle. J Reprod Fertil;108:271-278.
11. Gumen, A., Keskin, A., Yilmazbas-Mecitoglu, G., Karakaya, E., Alkan, A., Okut, H., and Wiltbank, M.C. (2012). Effect of presynchronization strategy before Ovsynch on fertility at first service in lactating dairy cows Theriogenology;78: 1830–1838.
12. Hopper, R.M. (2015). Bovine Reproduction First published, Starkville, Mississibbi, USA, ؛pp;819.
13. Lubbadeh, W.F., and Alnimer, M.A. (2003(. Different postpartum hormonal treatments for improving fertility in dairy cows. Dirasat Agricultural Sciences;30:304-310.
14. Nett T. (1987). Function of the hypothalamic–hypophysial axis during the postpartum period in ewes and cows. J Reprod Fertil Suppl;34:201-213.
15. Noakes, D.E., Parkinson, T.J., England, G.C.W., and Arthur'. (2001). Veterinary Reproduction and Obstetrics Eighth Edition published USA,pp 868.
16. Patel, O., Takenouchi, N., Takahashi, T., Hirako, M., Sasaki, N., and Domeki. (1999). Plasma oestrone and oestradiol concentrations throughout gestation in cattle: relationship to stage of gestation and fetal number. Res Vet Sc;66:129-133.
17. Peter, A., Vos, P., and Ambrose, D. (2009). Postpartum anestrus in dairy cattle. Theriogenology;71:1333–1342.
18. Poso Jukka, and Esa Miintysaari, A. (1996). Genetic relationships between reproductive disorders, operational days open and milk yield. Livestock Production Science 46 (1996) 41-48.
19. Pursley, J.R., Meez, M.0., and Wiltbank, M.C. (1995). Synchronization of Ovulation in Dairy Cows Using PGF2α, and GnRH. Theriogenology 44:915-923,1.
20. Pursley, J.R., Roy, W., Silcox., and Wiltbank, M.C. (1998). Effect of Time of Artificial Insemination on Pregnancy Rates, Calving Rates, Pregnancy Loss, and Gender Ratio After Synchronization of Ovulation in Lactating Dairy Cows. Journal of Dairy Science Vol. 81, No. 8.
21. Roelofs, J., López-Gatius, F., Hunter, R.H.F., van Eerdenburg, F.J.C.M., and Hanzen, C.h. (2010). When is a cow in estrus? Clinical and practical aspects. Theriogenology 74 ;327–344.
22. Saacke, R.G. (2008). Sperm Morphology: Its Relevance to Compensable and Uncompensable Traits in Semen. Theriogenology ;70:473-478.
23. Shamoun, A.I., and Alnimer, M.A. (2011). Effect of Different Hormonal Treatments for Synchronizing Estrus on Fertility of Lactating Dairy Cows. Jordan Journal of Agricultural Sciences, Volume 7, No.4.
24. Wiltbank, M., Lopez, H., Sartori, R., Sangsritavong, S., and Gumen, A.M. (2006). Changes in reproductive physiology of lactating dairy cows due to elevated steroid metabolism. Theriogenology;65: 17–29.