Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2007.363.367TowhidiA. MasoumiR. MoeiniM.M. SolgiH. MoravejH. 22007102The aim of this study was to determine the relationship between plasma leptin and FSH concentration in Iranian sheep. Forty female Mehraban and Sanjabi sheep were used. All ewes were cyclic and synchronized with cloprestenol. The ewes were divided into two breed groups: Mehraban breed (n = 20) and Sanjabi breed (n = 20), feeding at maintenance level. On the first and second days of estrus cycle, blood samples were collected from the jugular vein. Ovulation number was determined by endoscopy 7 days after the second injection. Mean Plasma leptin concentrations on second day (4.74±0.15 and 4.68±0.10 ng mL-1) were significantly higher than those on first day (2.64±0.11 and 2.56±0.04 ng mL-1) for Mehraban and Sanjabi sheep, respectively (p<0.01). Mean plasma FSH concentrations on second day (2.75±0.17 and 2.74±015 ng mL-1) were also significantly greater than those on first day (1.19±0.05 and 1.19±0.04 ng mL-1) for Mehraban and Sanjabi ewes, respectively (p<0.01). In the present study, positive relationship has been shown between plasma Leptin and FSH concentrations (p<0.01) in Mehraban and Sanjabi sheep. Ovulation rate had a significant difference between Mehraban (1.20±0.33) and Sanjabi (1.07±0.1) ewes. Significant differences were not observed between concentrations of FSH and leptin with ovulation rate in both breeds (p≤0.01).]]>Ahima, R.S., J. Dushay, S.N. Flier, D. Parbakaran and J.S. Flier,199799391395Barash, I.A., C.C. Cheung, D.S. Weigle, H. Ren and E.B. Kabigting et al.,199613731443147Barb, C.R.,19997712491257Blum, W.F., P. Englaro, S. Hanitsch, A. Juul and N.T. Hertel et al.,199782290429010Castracane, V.D., R.R. Kraemer, M.A. Franken, G.R. Kraemer and T. Gimpel,199870472477Chehab, F.F., M.E. Lim and R. Lu,199612318320Chehab, F.F., K. Mounzih, R. Lu and M.E. Lim,19972758890Cheung, C.C., J.E. Thornton, J.L. Kuijper, D.S. Weigle, D.K. Clifton and R.A. Steine,1997138855858Chu, S.C., Y.C. Chou, J.Y. Liu, C.H. Chen, J.C. Shyu and F.P. Chou,19996422992306Cioffi, J.A., A.W. Shafer, T.A. Zupancic, J. Smith-Gbur, A. Mikhail, D. Platika and H.R. Snodgrass,19962585859Finn, P.D., M.J. Cunningham, K.Y. Pau, H.G. Spies, D.K. Clifton and R.A. Steiner,199813946524662Gruaz, N.M., M. Lalaoui, D.D. Pierroz, P. Englaro, P.C. Sizonenko, W.F. Blum and M.L. Aubert,199810627633Horlick, M.B., M. Rosenbaum, M. Nicolson, L.S. Levine and B. Fedun et al.,20008525092518Hossner, K.L.,199878463472Keisler, D.H., J.A. Daniel and C.D. Morrison,199954425435Kennedy, A., T.W. Gettys, P. Watson, P. Wallace, E. Ganaway, Q. Pan and W.T. Garvey,19978212931300Kiess, W., A. Reich, K. Meyer, A. Glasow and J. Deutscher et al.,1999515563Kosior-Korzecka, U. and R. Bobowiec,200350343343Masuzaki, H., Y. Ogawa, N. Sagawa, K. Hosoda and T. Matsumoto et al.,1997310291033Plant, T.M. and A.R. Durrant,199713845054508Rogol, A.,19838310891091Teirmaa, T., V. Luukkaa, J. Rouru, M. Koulu and R. Huupponen,1998139406411Towhidi, A., H. Khazali, F. Rostami and A.H. Ahadi,20032003Yu, W.H., M. Kimura, A. Walczewska, S. Karanth and S.M. McCann,19979410231028Zhang, Y., R. Proenca, M. Maffei, M. Barone, L. Leopold and J.M. Friedman,1994obese gene and its human homologue.]]>372425432