Effect of early tail-docking on luteinizing hormone pulse frequency in fat-tailed Tuj ewe-lambs

The aim of the study was to investigate the effect of tail-docking on the LH pulse frequency in female Tuj lambs. Twelve female lambs were assigned into two equal groups. A rubber ring was applied to the base of the tail for shedding off. Blood samples were collected for 8 h in the 4th and 8th months of age to determine pulsatile secretion of LH. Starting from the age of 6 months، blood samples were taken thrice weekly for progesterone analyses. There was no LH pulse in the first LH analysis but the pulses were observed in both groups in the second LH analysis. However، number of pulses was not different between groups. The plasma progesterone level was less than 1 ng/ml throughout the breeding season. In conclusion، there was no effect of the tail-docking on pulsatility of LH in fat-tailed female lambs.