Effect of Gonadotropin Releasing Hormone Treatment on Semen Characteristics and Enzymatic Activities of Awassi Rams in Breeding and Non Breeding Seasons

Document Type : Research Articles

Authors

1 Department of Surgery and Theriogenology, College of Veterinary Medicine, University of Mosul, Mosul, Iraq

2 Department of Animal Resources,College of Agriculture and Forestry, University of Mosul, Mosul, Iraq

Abstract

This study was aimed to evaluate the effect of GnRH injection on semen ejaculate characteristics in Awassi rams collected in breeding and non breeding seasons. The study was conducted in late summer to early autumn when breeding activity commences, and in winter during the non breeding season. Twelve mature Awassi rams were used in this study. Animals were randomly allocated into two equal groups, the experimental group received 50 µg IM of GnRH weekly andthe control group received 1 ml of saline. Libido was assessed and semen samples were collected from the Awassi rams 24 hours after IM administration. Scrotal circumference (SC) and testicular volume were measured weekly during the study period. Ejaculates were collected 24 hours after each GnRH/saline administration and assessed for volume, sperm concentration, mass and individual motility, live sperm and sperm abnormalities. Seminal plasma was assayed for the estimation of alanine amino transferase (ALT), aspartate amino transferase (AST), acid phosphatase (ACP), alkaline phosphatase (ALP) and lactic dehydrogenase (LDH). Results show that GnRH treatment improves semen volume, total ejaculated sperm and reaction time in both breeding and non-breeding seasons compared to control (P<0.05). However, GnRH treatment reduces the activity of LDH in both seasons. Other seminal traits show similar values for both seasons. In conclusion, GnRH treatment of Awassi rams improved libido, semen volume, sperm numbers, but not sperm viability.

Keywords


AdamsT. E., Daley C. A., Adams B. M. and Sakuri H. (1996). Testes function and feedlot performance of bulls actively immunized against Gonodotropin-Releasing hormone: Effect of age at immunization. J. Anim. Sci. 72, 950-954.
Almquist J.O. (1973). Effects of sexual preparation on sperm output, semen characteristics and sexual activity of beef bulls with a comparison to dairy bulls. J. Anim. Sci. 36, 331-336.
Azawi O.I., Znad M.M. and Al-Jarrah L.H. (1990a). The correlation between the viability of bovine spermatozoa preserved at ambient temperature and the activity of transferases. Anim. Reprod. Sci. 23, 319-323.
Azawi O.I., Znad M.M. and Al-Jarrah, L.H. (1990b). The effect of preserving bovine spermatozoa at ambient temperature on the release of phosphatases and lactic dehydrogenases enzymes. Indian J. Reprod. 11, 1-5.
Chauhan M.S., Kapila R., Gandhi K.K. and Anand S.R. (1994). Acrosome damage and enzyme leakage of goat spermatozoa during dilution, cooling and freezing. Andrologia.26, 21-26.
Deldar Tajangookeh A., Zare Shahneh A., Moradi Shaherbabak M. and Shakeri M. (2007). Monthly variation of plasma concentrations of testosterone and thyroid hormones and reproductive characteristics in three breeds of Iranian fat-tailed rams throughout one year. Pak. J. Bio. Sci. 10, 3420-3424.
Foote R. H. (1978). Factors influencing the quantity and quality of semen harvested from bulls, rams, boars and stallions. J. Anim. Sci. 47, 1-7.
Gabor G., Sasser R.G., Kastelic J.P., Coulter G.H., Everson D.O., Falkay G., Meezes M., Bozo S., Cook R.B., Volgyi J.C., Barany I. and Szaasz J.F. (1998). Endocrine and thermal responses to GnRH treatment and prediction of sperm output and viability in Holstein-Friesian breeding bulls. Theriogenology. 50, 177-183.
Glover T.D., D’Occhio M.J. and Millar R.P. (1990). Male life cycle and seasonality. In: Marshall’s Physiology of Reproduction. Vol II. Reproduction in the Male. Lamming, G.E. (Ed.), 4th Ed. Churchill Livingstone, London. Pp. 213-378.
Henry J.B. (1974). Clinical diagnosis and management by laboratory method. Am. J. Clin. 61, 108.
Ibrahim S.A.(1997). Seasonal variations in semen quality of local and crossbred rams raised in the United Arab Emirates. Anim. Reprod. Sci. 49, 161-167.
Kafi M., Safdarian M. and Hashemi M. (2004). Seasonal variation in semen characteristics, scrotal circumference and libido of Persian Karakul rams. Small Rumin. Res. 53, 133-139.
Karagiannidis A., Varsakeli S., Alexopoulos C. and AmarantididI.(2000). Seasonal variation in semen characteristics of Chios and Friesian rams in Greece. Small Rumin. Res. 37, 125-130.
King P.R.N. and King E.J. (1954). Estimation of plasma phosphatase by determination of hydrolysed phenol with amino-anti-antipyrine. J. Clin. Pathol. 7, 322-326.
LincolnG.A. and Short R.V. (1980). Seasonal breeding: nature’s contraceptive. Rec. Prog. Horm. Res. 36, 1-52.
Makawi S.A., Elsharif B.A. andBabiker E.A. (2007). Effect of season on freezability of semen from two breed types of desert sheep in the Sudan. J. Anim. Vet. Adv. 6, 846-849.
Maule J.P. (1962). The Semen of Animals and Artificial Insemination. Commonwealth Agricultural Bureaux, Farnham Royal, U.K.
Mekonnen G., Boland M. and Gordon I. (1989). The effect of prostaglandin on semen production and libido in the ram. Irish Vet. J. 2, 56-62.
Perez G.R., Lopez A., Castrillejo A., Bielli A., Laborde D., Gastel T., Agle R., Queirolo D., Franco J., Forsberg M. and Rodriguez-Martinez H. (1997). Reproductive seasonality of Corriedale rams under extensive rearing conditions. Acta. Vet. Scand. 38, 109-117.
Piperelis S.G., Vafiadis D., Boscos C.M., Brozos C., Kiossis E. and Alexopoulos C. (2008). Efficiency assessment of a swift method to enhance substandard viability ram ejaculates. Reprod. Domest. Anim. 43, 111-116.
Pursel V.G., Johnson I.A. and Gerrits P.J. (1968). Glutamic oxaloacetic transaminase and lactic dehydrogenase activities of boar spermatozoa and seminal plasma. J. Reprod. Fertil. 18, 176-177.
Purswell B.J. and Wilcke J.R. (1993). Response to gonadotrophin-releasing hormone by the intact male dog: serum testosterone, luteinizing hormone and follicle stimulating hormone. J. Reprod. Fertil. Suppl. 47, 335-339.
Reitman S. and Frankel S.A. (1957). Colorimetric method for the determination of serum glutamic oxaloacetic and glutamic pyruvic transaminases. Am. J. Clin. Pathol. 28, 56-63.
Roussal J.D. and Stallcup O.T. (1965). Activity of lactic dehydrogenase and its isozymes in bovine semen. J. Dairy Sci. 48, 1506.
Sajjad M., Ali S., Akhter S. and Ullah N. (2007). Effect of gonadotropin releasing hormone on semen characteristics in Nili-Ravi buffalo bulls. Pakistan. Vet. J.27, 153-154.
Sieme H., Bonk A., Hamann H., Klug E. and Katila T. (2004). Effects of different artifi cial insemination techniques and sperm doses on fertility of normal mares and mares with abnormal reproductive history. Theriogenology. 62, 915-928.
Stellflug J.N. (2002). Influence of classification levels of ram sexual activity on spring breeding ewes. Anim. Reprod. Sci. 70, 203-214.
Stellflug J.N. and Lewis G.S. (2007). Effect of early and late exposure to estrual ewes on ram sexual performance classifications.Anim. Reprod. Sci. 97, 295-302.
Tietz N.W. (1999). Text Book of Clinical Chemistry. 3rd Ed. Saunders Co., USA.
Wells M.E. and Awa O.A. (1970). New technique for assessing acrosomal characteristics of spermatozoa. J. Dairy Sci. 53, 227-232.
Yousef M.I. and Zeitoun M.M. (1998). Bovine ovarian follicular fluids modulate the release of transaminases, acrosome reaction and motility of the rabbits sperm in vitro. AlexandriaJ. Agric. Res. 43, 17-26.
Zamiri M.J. and Khodaei H.R. (2005). Seasonal thyroidal activity and reproductive characteristics of Iranian fat-tailed rams. Anim. Reprod. Sci. 88, 245-255.