Mustafa Kemal SARIBAY, Ramazan SERTKOL

Laktasyondaki İneklerde Tohumlama Anında Azaltılan GnRH Dozunun Gebelik Oranı Üzerine Etkisi

Çalışma laktasyondaki ineklerde tohumlama anında uygulanan GnRH dozunun yarıya indirilmesinin gebelik oranı üzerine etkisini belirlemek amacıyla yapıldı. Araştırmada yaşları 3-6 arasında değişen, postpartum 80-120 günler arasında olan ve klinik olarak herhangi bir reprodüktif probleme rastlanılmayan 50 Holstayn ırkı inek kullanıldı. İneklerin östrüs göstermeleri için herhangi bir hormonal uygulama yapılmadı. Çalışma süresince östrüs belirtileri gösteren ineklerin ovaryum muayeneleri 6-8 MHz lineer problu real-time ultrason ile yapıldı ve ovaryumdaki mevcut foliküllerin çapı kaydedildi. Daha sonra bir gruba (grup I, n=25) suni tohumlama (ST) anında bir gonadotropin salgılatıcı hormon (GnRH) analoğu olan Buserelin asetat (Receptal®, İntervet) 2.5 mL kas içi uygulandı. Diğer gruba (grup II, n=25) ise ST anında 1.25 mL Buserelin asetat kas içi uygulandı. Folikül çapları grup I ve II’de sırasıyla 12.28±0.37 mm, 12.24±0.44 mm olarak kaydedildi. Gebelik oranları grup I ve II’de sırasıyla %80 (20/25), %72 (18/25) olarak belirlendi (P>0.05). Sonuç olarak, ineklerde gebelik oranlarının artırılması amacıyla ST sırasında uygulanan GnRH’nın dozunun yarıya indirilmesinin gebelik oranlarını etkilemediği görüldü.

Anahtar Kelimeler:

İnek, GnRH, Gebelik oran

The Effect of Reduced Dose of GnRH Administered at the Time of Insemination on Pregnancy Rate in Lactating Dairy Cows

This study was carried out to determine the effect of reducing half dose of GnRH performed immediately at the time of artificial insemination on pregnancy rate in lactating dairy cows. The study was conducted on 50 Holstein cows aging between 3-6 years old, and on 80-120 days postpartum without reproductive problems. No hormonal application was carried out for ensuring estrous in cows. The ovarian examinations of the cows showing estrous symptoms were performed by real-time ultrasound with 6–8 MHz lineer probe and the diameters of the follicles were recorded. The cows in Group I (n=25), a gonadotropin releasing hormone (GnRH) analogue, buserelin acetate (Receptal®, İntervet) recieved 2.5 ml of GnRH intramucularly just at the time of artificial insemination. Group II recieved 1.25 mL of GnRH, intramuscularly immediately at the same time. The diameters of follicles at the time of inseminations were detected as 12.28±0.37 mm, 12.24±0.44 mm in the group I and group II respectively. The pregnancy rates were 80% (20/25) and 72% (18/25), in group I and group II respectively (P>0.05). It was concluded that reducing the half dose of GnRH, which is performed to increase the pregnancy rate in cows immediately at the time of insemination, did not affect the pregnancy rate.

Keywords:

Cow, GnRH, Pregnancy rate,

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Alaçam E, T Tekeli, Gökçay Y, 1986: Sütçü ineklerde gonadotropin salgılayıcı hormon (gnrh) enjeksiyonu ile gebelik oranlarının yükseltilmesi üzerinde çalışma. Eurasian J Vet Sci, 2, 1, 27- 35.
Alaçam E, 1999: İnekte infertilite sorunu. Alınmıştır “Evcil Hayvanlarda Doğum ve İnfertilite”, Ed; Alaçam E, Medisan Yayınevi, Ankara.
Anjum IA, Usman RH, Tunıo MT, Abro SH, 2010: Improvement of conception rate in crossbred cattle by using GnRh analogue therapy. Agricultura Tropica et Subtropica, 43, 1, 6-10.
Arthur GH, Noakes DE, Pearson H, 1989: Veterinary Reproduction and Obstetrics (Theriogenology), 6th ed, Bailliere Tindall, London.
Dinç DA, 1990: Döl Tutmayan (Repeat Breeder) Hayvanlar. Alınmıştır “Evcil Hayvanlarda Reprodüksiyon, Suni Tohumlama, Obstetrik ve İnfertilite”, Ed; Alaçam E, Nurol Matbaası, Ankara.
Fricke PM, Guenther JN, Wiltbank MC, 1998: Efficacy of decreasing the dose of GnRH used in a protocol for synchronization of ovulation and timed AI in lactating dairy cows. Theriogenology, 50,1275-1284.
Ginther OJ, Wiltbank MC, Fricke PM, Gibbons JR, Kot K, 1996: Selection of the dominant follicle in cattle. Biol Reprod, 55, 1187-1194.
Grunert E, Tholen I, Goldbeck U, 1978: Influence of synthetic gonadodotrophin releasing hormone on the effectiveness of artificial insemination in cows. Blue Book, 28, 313-324.
Hailu B, Gebrekidan B, Raju S, Birhanu A, Tadesse G, 2015: Effects of gonadotropin releasing hormone analogue in enhancements of pregnancy in repeat breeding dairy cows in and around Mekelle, Tigray, Ethiopia. Anim Vet Sci, 3, 1, 12-17.
Hartıgan PJ, 1995: Cattle breeding and infertlity. In “Animal Breeding and Infertility”, Blackwell Science, London, 86-168.
İleri K, Ak K, Pabuççuoğlu S, Usta S, 1998: Reprodüksiyon ve Suni Tohumlama. İstanbul Üniv. Vet. Fak. Yayınları, No: 84, 139-145.
Jainudeen MR, Wahid H, Hafez ESE, 2000: Reproduction and Farm Animals. In: Reproductive cyles, cattle and water buffalo. 7nd ed., A Wolters Kluver, Company, Philadelphia.
Karaca F, Doğruer G, Sarıbay MK, Ergün Y, Ateş CT, 2009: Laktasyondaki ineklerde ovsink protokolünde azaltılan gnrh dozunun ovulatör follikül çapı, ovulasyon oranı ve gebe kalma oranı üzerine etkisi. V. Ulusal Reprodüksiyon ve Suni Tohumlama Kongresi. pp: 102-103, Elazığ, Türkiye.
Kharche SD, Srivastava SK, 2007: Dose dependent effect of GnRH analogue on pregnancy rate of repeat breeder crossbred cows. Anim Reprod Sci, 99, 1-2, 196-201.
Kimura M, Nakoo T, Moriyoshi M, Kawata K, 1987: Luteal Phase deficiency as apossible cause of repeat breeding in dairy cows. Br Vet J, 143, 6, 560-566.
King WA, 1991: Embryo-mediated pregnancy failure in cattle. Can Vet J, 32, 99-103.
Lafi SQ, Kaneene JB, 1988: Risk factors and associated economic effect of the repeat breeder syndrome in dairy cattle. Veterinary Bulletin, 58, 891-903.
Lee CN, Maurice E, Pennington JA, Hoffman WF, Brown MD, 1983: Efficacy of gonadotropin- releasing hormone administered at the time of artificial insemination of heifers and postpartum and repeat breeder dairy cows. Am J Vet Res, 44, 2160-2163.
Lucy MC, Savio JD, Badinga L, De La Sota RL, Thatcher WW, 1992: Factors that affect ovarian follicular dynamics in cattle. J Anim Sci, 70, 3615-3626.
Macmillan KL, Taufa VK, Day AM, 1986: Effects of an agonist of gonadotrophin releasing hormone (Buserelin) in cattle. III. Pregnancy rates after a post-insemination injection during metoestrus or dioestrus. Anim Reprod Sci, 11, 1-10.
Martin TL, Swanson LV, Appell LH, Rowe KE, Stormshak F, 1990: Response of the bovine corpus luteum to increased secretion of luteinizing hormone induced by exogenous gonadotropin releasing hormone. Dom Anim Endocrinol, 7, 27-34.
Martinez MF, Adams GP, Bergfelt DR, Kastelic JP, Mapletoft RJ, 1999: Effect of LH or GnRH on the dominant follicle of the first follicular wave in beef heifers. Anim Reprod Sci, 57, 23-33.
Mee MO, Stevenson JS, Scoby RK, Folman Y, 1990: Influence of gonadotropin-releasing hormone and timing of insemination relative to estrus on pregnancy rates of dairy cattle at first service. J Dairy Sci, 73, 1500-1507.
Peters AR, 2005: Veterinary clinical application of GnRH - questions of efficacy. Anim Reprod Sci, 88, 155-167.
Phatak AP, Whitmore HL, Brown ND, 1986: Effect of gonodotrpin relasing homone on conception rate in repeat breeder dairy cows. Theriogenology, 26, 5, 605-609.
Pursley JR, Mee MO, Wiltbank MC, 1995: Synchronization of ovulation in dairy cows using PGF2alpha and GnRH. Theriogenology, 44, 915-923.
Pursley JR, Kosorok MR, Wiltbank MC, 1997: Reproductive management of lactating dairy cows using synchronization of ovulation. J Dairy Sci, 80, 301-306.
Rastegarnia A, Niasari-Naslaji A, Hovareshti P, Sarhaddi F, Safaei M, 2004: The effect of different doses of Gonadorelin on ovarian follicle dynamics in river buffalo (Bubalus bubalis). Theriogenology, 62, 7, 1283-1291.
Rodger LD, Stormshak F, 1986: Gonadotropin-releasing hormone-induced alteration of bovine corpus luteum function. Biol Reprod, 35, 149-156.
Rosenberg M, Chun SY, Kaim M, Herz Z, Folman Y, 1991: The effect of GnRH administered to dairy cows during oestrus on plasma LH and conception in relation to the time of treatment and insemination. Anim Reprod Sci, 24, 13-24.
Schneider F, Tomek W, Gründker C, 2006: Gonadotropin-releasing hormone (GnRH) and its natural analogues: A review. Theriogenology, 66(4), 691-709.
Srivastava SK, Kharche SD, 2002: Effect of GnRH on fertility in crossbred cows. Indian J Anim Sci, 72, 6, 428-430.
Taponen J, Katila T, Rodríguez-Martínez H, 1999: Induction of ovulation with gonadotropinreleasing hormone during proestrus in cattle: influence on subsequent follicular growth and luteal function. Anim Reprod Sci, 55, 2, 91-105.
Taponen J, 2003: Ovarian function in dairy cattle after gonadotropin-releasing hormone treatments during perioestrus. Academic Dissertation, University of Helsinki, Finland.
Thatcher WW, Drost M, Savio JD, Macmillan KL, Entwistle KW, Schmitt EJ, de la Sota RL, Morris GR, 1993: New clinical uses of GnRH and its analogues in cattle. Anim Reprod Sci, 33, 27-49.
Yamada K, Nakao T, Nakada K, Matsuda G, 2002: Influence of GnRH analogue (Fertirelin acetate) doses on synchronization of ovulation and fixed-time artificial insemination in lactating dairy cows. Anim Reprod Sci, 74, 27-34.