Abstract
This experiment was conducted to evaluate the effect of administering hormonal treatments (melatonin and progestagen/equine chronic gonadotropin (eCG)) on advancing puberty in Awassi ewe lambs. Fifty-one 6-month-old ewe lambs of similar body weights (around 28 kg) were randomly assigned into four treatment groups; control (CON; n = 14), melatonin (MEL; n = 13), melatonin plus progestagen–eCG (MELPP; n = 11), and progestagen–eCG (PP; n = 13). Ewe lambs in the PP and MELPP groups were fitted with intravaginal progestagen sponges containing 60 mg medroxyprogesterone acetate for 14 days; 400 IU eCG were administered to each of these ewe lambs on the day of sponge removal. Ewe lambs in the MEL and MELPP groups received subcutaneous melatonin implants (Regulin®, 18 mg melatonin) 36 days before sponge insertion. Hormonal treatment had no effect on ewe lamb body weight change. Estrous behavior was greater (p < 0.001) in the PP and MELPP groups than in the CON and MEL ewe lambs. The duration from ram introduction to onset of estrus was shorter (p < 0.05) in the CON, PP, and MELPP than in the MEL ewe lambs. The number of ewe lambs showing luteal activity was greater (p < 0.001) in the MELPP and PP than in the CON and MEL groups. Lambing rate from mating during the first cycle following ram introduction differed significantly (p < 0.01) among treatments being greater in the MELPP and PP than in the CON and MEL groups. Based on these results, it can be concluded that progestagen–eCG appears to be more effective than melatonin in inducing reproductive activity. However, the majority of ewe lambs in the current study either failed to cycle or stopped cycling following the induced estrus. Such failure in advancing puberty may be related to body weight of ewe lambs at the time of mating.
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References
Anderson, L.H., McDowell, C.M., and Day, M.L., 1996. Progestin-induced puberty and secretion of luteinizing hormone in heifers, Biology of Reproductions, 54, 1025–1031.
Awawdeh, M.S., Obeidat, B.S., and Kridli, R.T., 2009. Yellow grease as an alternative energy source for nursing Awassi ewes and their suckling lambs. Animal Feed Science and Technology, 152, 165–174.
Chagas e Silva, J., Lopes, D.A., Costa, L., Cidadao, R., and Robalo Silva, J., 2003. Plasma progesterone profiles, ovulation rate, donor embryo yield and recipient embryo survival in native Saloia sheep in the fall and spring breeding seasons, Theriogenology, 60, 521–532.
Epstein, H., 1977. The Awassi sheep in Israel. World Review of Animal Production, 32,19-26.
Flores-Najera, M.J., Meza-Herrera, C.A., Echavarria, F.G., Villagomez, E., Iñiguez, L., Salinas, H., and Gonzalez-Bulnes, A., 2010. Influence of nutritional and socio-sexual cues upon reproductive efficiency of goats exposed to the male effect under extensive conditions. Animal Production Science. 50, 897–901.
Forcada F., Abecia, J.A., Casao, A., Cebrian-Perez, J.A., Muino-Blanco, T., and Palacin, I., 2007. Effects of ageing and exogenous melatonin on pituitary responsiveness to GnRH in ewes during anestrus and the reproductive season, Theriogenology, 67, 855–862
Foster, D.L. and Olster, D.H., 1985. Effect of restricted nutrition on puberty in the lamb: patterns of tonic luteinizing hormone (LH) secretion and competency of the LH surge system. Endocrinology, 116, 375–381.
Gonzalez-Bulnes, A., Meza-Herrera, C.A., Rekik, M., Ben Salem, H., and Kridli R.T., 2010. Limiting factors and strategies for improving reproductive outputs of small ruminants reared in semi-arid environments. In: Semi-arid environments: Agriculture, water supply and vegetation. Ed: K.M. Degenovine. Nova Science Publishers Inc. Hauppauge, NY, USA.
Guerra-García, M., Meza-Herrera, C.A., Sanchez-Torres-Esqueda, M.T., Gallegos-Sanchez, J., Torres-Hernandez, G., and Pro-Martinez, A., 2009. IGF-1 and ovarian activity of goats in divergent body condition and supplemented with non-degradable ruminal protein. Agrociencia. 43, 241–247.
Horoz, H., Kasikci, G., AK, K., Alkan, S. and Sonmez, C., 2003. Controlling the breeding season using melatonin and progestagen in Kivircik ewes, Turkish Journal of Veterinary and Animal Science, 27, 301–305.
Karsch, F.J., Bittman, E.L., Foster, D.L., Goodman, R.L., Legan, S.J., and Robens, J.E., 1984. Neuroendecrine basis of seasonal reproduction, Recent Progress in Hormone Research, 40, 185–223.
Kassem, R., Owen, J.B., and Fadel, I., 1989. The effect of pre-mating nutrition exposure to the presence of rams on the onset of puberty in Awassi ewe lambs under semi-arid conditions. Animal Production, 48, 393–397.
Kennaway DJ, Gilmore, T.A., and Dunstan, E.A., 1985. Pinealectomy delays puberty in ewe lambs, Journal of Reproduction and Fertility, 74, 119 –25.
Kridli, R.T., Abdullah, A.Y., Momani Shaker, M., and Al-Momani, A.Q., 2006a. Age at puberty and some biological parameters of Awassi and its first crosses with Charollais and Romanov rams, Italian Journal of Animal Science, 5, 193–202.
Kridli, R.T., Husein, M.Q., Muhdi, H.A., and Al-Khazaleh, J.M., 2006b. Reproductive performance of hormonally-treated anestrous Awassi ewes, Animal Reproduction, 3, 347–352.
Laliotis, V., Vosniakou, A., Lymberopoulos, A., Doney, J.M., and Kouimtzis, S., 1997. The effect of melatonin treatment in combination with progestagen pessaries on reproductive performance of ewes during the anestrous period, Journal of Animal Science 65, 71–74.
Meza-Herrera, C.A. 2008. Regluatory mechanisms of puberty in female goats: Recent concepts. Tropical and Subtropical Agroecosystems, 9, 29–38.
Meza-Herrera, C.A., Gonzalez-Bulnes, A., Kridli, R., Mellado, M., Arechiga-Flores, C.F., Salinas, H., and Luginbhul, J.M. (2010b) Neuroendocrine, metabolic and genomic cues signaling the onset of puberty in females. Reproduction in Domestic Animals, doi:10.1111/j.1439-0531.2009.01355.x
Meza-Herrera, C.A., Veliz-Deras, F.G., Wurzinger, M., Lopez-Ariza, B., Arellano-Rodriguez, G., and Rodriguez-Martinez, R., 2010a. The kiss-1, kisspeptin, gpr-54 complex: A critical modulator of GnRH neurons during pubertal activation. Journal of Applied Biomedicine, 8, 1–9.
Mura, M.C., Luridiana, S., Vacca, G.M., Bini, P.P., and Carcangiu, V., 2010. Effect of genotype at the MTNR1A locus and melatonin treatment on first conception in Sarda ewe lambs. Theriogenology, 74, 1579–1586.
Nowak, R., and Rodway, R.G., 1985. Effect of intravaginal implants of melatonin on the onset of ovarian activity in adult and prepubertal ewes, Journal of Reproduction and Fertility, 74, 287–93.
Oqla, H.M., 2003. The effect of dietary fat inclusion on nutrient intake and reproductive performance in postpartum Awassi ewes. Master’s thesis, Jordan University of Science and Technology. p. 44–45.
Papachristoforou, C., Koumas, A., and Photiou, C., 2007. Initiation of the breeding season in ewe lambs and goat kids with melatonin implants, Small Ruminant Research, 73, 122– 126.
Rajkumar, R.R., Argo, C.M., and Rodway, A.G., 1989. Fertility of ewes given either melatonin or progestagen sponges, The Veterinary Record, 124, 215–217.
Rekik, M., Lassoued, N., and Yacoubi, C., 2002. Reproductive performances in ewe lambs of the Queue Fine de l’Ouest breed and their D’Man crosses following synchronization, Small Ruminant Research, 45, 75–78
Safranski, T.J., Lamberson, W.R., and Keisler, D.H., 1992. Use of melengestrol acetate and gonadotropins to induce fertile estrus in seasonally anestrous ewes, Journal of Animal Science, 70, 2935–2941.
SAS, 1994. Institute-State User’s Guide Release 6.03 Edition. SAS Institute INC, Cary, North Carolina.
Sharafeldin, M.A., Ragab, M.T., and Khalil, I.A., 1969. Sexual behaviour of female lambs as affected by the plane of nutrition. World Review of Animal Production, 5, 83–86.
Stellflug, J.N., LaVoie, V.A., and Glimp, H.A., 1994. Influence of stimulated photoperiod Alteration and induced estrus on reproductive performance of spring-Born Columbia and Targhee ewe lambs, Journal of Animal Science 72, 29–33.
Titi, H.H., and Kridli, R.T., 2008. Reproductive performance of seasonal ewes fed dry fat source during their breeding season. New Zealand Journal of Agricultural Research, 51, 25–32.
Urrutia-Morales, J., Meza-Herrera, C.A., Escobar-Medina, F.J., Gamez-Vazquez, H.G., Ramirez-Andrade, B.M., Diaz-Gomez, M.O., and Gonzalez-Bulnes A., 2009. Relative roles of photoperiodic and nutritional cues in modulating ovarian activity in goats. Reproductive Biology, 9, 283–294.
Vinoles, C., Forsberg, M., Banchero, G., and Rubianes, E., 2001. Effect of long-term and short-term progestagen treatment on follicular development and pregnancy rate in cyclic ewes, Theriogenology, 55, 993–1004.
Zarkawi, M., Al-Merestani, M.R., and Wardeh, M.F., 1999. Induction of synchronized oestrous and early pregnancy diagnosis in Syrian Awassi ewes, outside the breeding season, Small Ruminant Research, 33, 99–102.
Acknowledgments
The authors wish to acknowledge the Deanship of Scientific Research at the Jordan University of Science and Technology and The National Center for Agricultural Research and Extension for funding this project. The assistance of Mr. Isam Shurman in data collection is highly appreciated.
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Sawalha, M.N., Kridli, R.T., Jawasreh, K.I. et al. The use of melatonin and progestagen–eCG to initiate reproductive activity in prepuberal Awassi ewe lambs. Trop Anim Health Prod 43, 1345–1350 (2011). https://doi.org/10.1007/s11250-011-9864-7
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DOI: https://doi.org/10.1007/s11250-011-9864-7