Atsan T., Emsen, E., Yaprak, M., Dagdemir, V. and Diaz, C. A. G. (2007). An economic assessment of differently managed sheep flocks in Eastern Turkey. Italian Journal Animal Science. 6:407-414.
Barrett, D. 2004. Ultrasound and endocrine evaluation of the ovarian response to a single dose of 500 IU of eCG following a 12-day treatment with progestogen-releasing intravaginal sponges in the breeding and nonbreeding seasons in ewes. Theriogenology. 61:311-327.
Chemineau, P., malpaux,B., thiery, J. C., Viguie, C., Morello, H., Zarazaga, L. and Pelletier, J. 1995. The control of seasonality: A challenge to small ruminant breeding. Proceeding of Reproduction and Animal Breeding. Advances and Strategy. 225-250.
Chemineau, P., Daveau, A., Pelletier, J., Malpaux, B. J., Karsch, F. and Viguie, C. 2003. Changes in the 5-HT2A receptor system in the pre-mammillary hypothalamus of the ewe are related to regulation of LH pulsatile secretion by an endogenous circannual rhythm.
BMC Neuroscience. 1:4-14.
English, J., Poulton, A. L., Arendt, J. and Symons, A. M. 1986. A comparison of the efficiency of melatonin treatments in advancing estrus in ewes. Journal of Reproduction and Fertility.77:321-327.
Jackson, G. L. Gibson, M. and Kuehl, D. 1988. Photoperiodic Disruption of Photorefractoriness in the Ewe. Biology of Reproduction. 38:127-134.
Karsch, F. J., Bittman, E. L., Foster, D. L., Goodman, R. L., Legan, S. J. and Robinson, J. E. 1984. Neuroendocrine basis of seasonal reproduction. Recent Progress in Hormone Research. 40: 185-232.
Karsch, F. J., Robinson, J. E., Woodfill, C. J. I. and Brown, M. B. (1989). Circannual cycles of luteinizing hormone and prolactin secretion in ewes during prolonged exposure to a fixed photoperiod: evidence for an endogenous reproductive rhythm. Biology of Reproduction. 41:1034-1046.
Kermani M. H. 2011. Ovarian response and pregnancy rate following different doses of eCG treatment in Chall ewes. Small Ruminant Research.
Knights, M., Hoehn, T., Lewise, P. E,. and Inskeep, E. K. (2001). Effectiveness of intravaginal progesterone inserts and FSH for inducing synchronized estrus and increasing lambing rate in anestrous ewes. Journal of Animal Science. 79:1120-1131
Kridli, R. T., Husein, M. Q., H. A. Muhdi and Khazeleh, J. M. 2006. Reproduction performance of hormonally- treated anestrous Awassi ewes. Journal of Animal. Reproduction. 3:347-352.
Luther, J.S., Grazul-Bilska, A. T., Kirsch, J. D., Weigl, R. M., Kraft, K. C., Navanukraw, C., Pant, D., Reynolds, L. P. and Redmer, D. A. 2007. The effect of GnRH, eCG and progestin type on estrous synchronization following laparoscopic AI in ewes. Small Ruminant Research 72: 227-231.
Powell, M. R., Kaps, M., Lamberson, W. R. and Keisler, D. H. (1996). Use of melengestrol acetate-based treatments to induce and synchronize estrus in seasonally anestrous ewes. Journal of Animal Science. 74:2292-2302.
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.
Umberger, S. H. (1996). Profitable Sheep Production through Spring Lambing. Cooperative Extension. Virginia State University.
Umberger, S. H. (1997). Management Strategies for Improved Fall-Lambing . Cooperative Extension. Animal and Poultry Sciences, Virginia State University.
)