Journal of Reproduction and Infertility 3 (1): 08-16, 2012 ISSN 2079-2166 © IDOSI Publications, 2012 DOI: 10.5829/idosi.jri.2012.3.1.63186 Corresponding Author: Mohamed M.M. Kandiel, Department of Theriogenology, Faculty of Veterinary Medicine, Benha University. P.O. 13736, Moshtohor, Tokheh, Kaliobia, Egypt. Tel: (002013) 2461-411. Cell: (0020111) 4988-544. Fax: (002013) 2463-074, E-mail: kandiel75@hotmail.com. 8 Ultrasound Imaging of the Testes and Accessory Sex Glands in Buffalo Bulls Treated with Gonadotrophic Releasing Hormone Ahmed R.M. El-Khawaga, Mohamed M.M. Kandiel, Gamal A. Sosa, Mahmoud E.A. Abou El-Roos, Alaa E. Abdel-Ghaffar and Abd El Salam I. El-Azab Department of Theriogenology, Faculty of Veterinary Medicine, Benha University, Benha, Egypt Abstract: The current study was designed to find out the effect of different doses (8, 12 or 16 μg) of GnRH analogue (Buserelin acetate, BA) on the ultrasonographic picture and biometry of buffalo bulls’ reproductive organs. Animals (n=9, aged 15-18 months) were allocated into three groups (n= 3/group) according to the hormonal dose that was administered once weekly for six weeks. Results revealed that the testicular diameter and epididymal tail width did not differ significantly before and after treatment. The epididymal tail length did not differ significantly before and after treatment with the 8μg, while it differed significantly (P<0.05) with doses of 12 and the 16 μg GnRH. The ampulla ductus deference and seminal vesicle heights differed significantly (P<0.05) before and after treatments. The prostatic body differed significantly (P<0.05) after treatments with 8 and 16 μg. The pars disseminate of prostate gland and the bulbourethral gland height did not differ significantly regardless the dose of treatment. The bulbourethral gland length differed significantly after treatment with the 8 μg, while it did not show significant differences with doses of 12 and the 16 μg of GnRH. In conclusion, the present results demonstrated that GnRH injection at a dose of 12 μg efficiently affect buffalo bulls reproductive organs. Moreover, ultrasonography is an affirmative indicator to the response of male reproductive system to exogenous GnRH analogue treatment. Key words: Buffalo bulls %GnRH %Prepubertal %Testosterone %Ultrasonography INTRODUCTION MATERIALS AND METHODS Gonadotrophic releasing hormone (GnRH) agonists Animals: The present study was carried out on a total and antagonists are increasingly used to modulate number of nine puberal Egyptian buffalo bulls belonged the fertility, behavior and productivity of male animals. to the Educational Farm - Faculty of Veterinary Medicine - The integrity of the hypothalamic-pituitary connection is Benha University. Bulls aged 15-18 months with 3-4 body essential for testicular maturation and function [1]. condition score [5] and 400-450 Kg body weight during Administration of estrogenic compounds (estradiol or the period from April to October, 2009. All animals were zeranol), suppressing the episodic release of GnRH via apparently normal, housed in free stall barn and fed a the hypothalamus, delayed the onset of puberty in bull balanced ration (14% crude protein, 15% crude fiber, 9% calves [2,3]. Increased episodic secretion of GnRH ash and 2% fat), as well as free access of the drinking heralds the onset of testicular maturation at puberty. A water and green fodders (clover in winter and corn crops significant correlation between testis volume and serum in summer). testosterone concentration has been indicated after injection of GnRH in Holstein- Friesian bulls [4]. Experimental Design: Animals (n=9) were allocated into The present investigation aimed to studying three groups (n= 3/group) according to the dose of changes in the reproductive organs (testes, epididymis Buserelin acetate (GnRH analogue; Receptal , Intervet and accessory sex glands) after treatment of Egyptian International B.V. European Union (EU)). GnRH was buffalo bulls with GnRH before age of puberty by injected i.m. at a dose of 8, 12 or 16 μg once weekly for six means of ultrasonographic and hormonal evaluation. weeks. Blood sampling and an ultrasound examination of ®