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For comparing reproductive performance of sexed versus conventional semen a total of 3573 heifer insemination records collected from five herds in four provinces of Iran were investigated. The studied provinces were classified into three regions: hot semiarid (Tehran and Alborz provinces), temperate semiarid (Khorasan Razavi province) and cold semiarid (Zanjan province). Various parameters including the conception rate, number of services per conception, calf sex ratio, calf birth weight, gestation length, calving ease score, abortion and stillbirth as well as twining rate were investigated. The logistic regression method was deployed for the analysis of categorical variables while the GLM procedure was applied for the analysis of continuous variables. The average conception rate of sex sorted and conventional semen was 48.3 and 63.8%, respectively. The utilisation of sex sorted semen resulted in 91.1% female calves. The conception rate, number of services per conception, gestation length, calf birth weight and the calf sex ratio were among the reproductive variables that were significantly influenced by the semen sexing. A greater number of services per conception and calving ease score were observed in hot and temperate semiarid areas. These climatic regions also provided a lower incidence of female calf births compared to the cold semiarid regions. Our results highly reaffirm the previous findings on the reproductive performance of sex sorted semen. Yet, climatic and management practices of a herd within a special climate have to be considered when deciding for utilisation of sex sorted semen in a dairy farm. [ABSTRACT FROM AUTHOR]

The genealogical data of Cashmere goat breed of South Khorasan province of Iran was analysed in this study. Records from a total of 10,635 animals collected during 1988–2014 from 20 registered flocks were analysed for evaluating pedigree parameters. The reference population was defined as the living reproductive animals born from 2010 till 2014. The average inbreeding coefficient in the studied breed was about 0.07% (ranging from 0 to 25%). In addition, the average inbreeding coefficient for the reference population was about 0.85%. The main reason for the low inbreeding level obtained in Cashmere goat population was related to the extensive production system and lack of sire registration in a large number of animals (about 78% missing sire information). A total of 200 animals were inbred. The inbred animals were all related to the breeding station flock which was acting as a closed nucleus flock and was under the control of Animal Breeding and Milk Improvement Centre of Iran. The result of analysis for gene origin parameters indicated the lack of pedigree depth, which could leads to management problems for conservation of the studied breed. [ABSTRACT FROM PUBLISHER]