melatonin regulates some major physiological processes such as maturation and function of reproductive system, pubertal development, seasonal reproduction and adaptation. the activation of melatonin hormone is mediated by melatonin receptor. previous studies showed melatonin receptor 1a gene (mtnr1a) is highly polymorphic in seasonally breeding species. the aim of the present study was detectio...

The present study was done to evaluate the breed, sex and sampling site influence on fat-tail and visceral fatty acid composition of five pure and cross bred lambs from three Iranian sheep breeds. Particularly, on the content of saturated and unsaturated fatty acids from two cut-able fat depots (fat-tail and visceral). All animals were managed and finished up together and received the same diet....

The present study was performed to study the effect of inbreeding on the pre-weaning growth traits including the birth weight (BW), weaning weight (WW), average daily gain (ADG), Kleiber ratio (KR) and lamb survival from birth to weaning (SUR) in Baluchi, Iran-Black and Zandi sheep. Significant positive inbreeding trends were found only for Baluchi and Iran-Black breeds as 0.038 and 0.278, resp...

The aim of this study was to monitor changes in genetic size of a small-closed population of Iranian Zandi sheep, by using pedigree information from animals born between 1991 and 2005. The genetic size was assessed by using measures based on the probability of identity-by-descend of genes (coancestry, f, and effective population size, N(e) ), as well as measures based on probability of gene ori...

Leptin (LEP), the expression product of the obese gene produced primarily in the adipose tissue, is related to feed intake, growth and lipid metabolism. The aim of this study was to study the possible association between polymorphism of the LEP gene with growth and carcass traits among three Iranian sheep breeds of the Shal, Zandi and Zel varieties. A total of 180 purebred animals of the Shal, ...

In this study, a method based on using image processing and artificial neural network is introduced to determine pelt color and curl size of newborn lambs in Zandi sheep. The data was collected from 300 newborn lambs reared in the Zandi sheep breeding centre of Khojir, Tehran. Primarily, curl size and pelt color of new born lambs was recorded by experienced appraisers, and at the same time, sev...

introduction the mating of related individuals produces an inbred offspring and leads to an increased homozygosity in the progeny, genetic variance decrease within families and increase between families. the ration of homozygosity for individuals was calculated by inbreeding coefficient. inbred individuals may carry two alleles at a locus that are replicated from one gene in the previous genera...