productive and reproductive traits have great importance in international dairy cattle breeding objectives. production, reproduction (days open and calving interval) and pedigree data of iranian holstein dairy cattles were collected between 2002 and 2012 from 47 herds in isfahan province. the data set consisted of 30179 records from 18837 registered iranianholstein dairy cattles. single trait r...

Heritabilities for milk, fat, and protein yields were estimated from first lactation data used for USDA-Dairy Herd Improvement Association (DHIA) genetic evaluations. Contemporary group assignments and standard deviations within herd-year were determined with the procedure used for national evaluations. Pedigree data were included for animals born since 1970; yield data were included for cows b...

Productive and reproductive traits have great importance in international dairy cattle breeding objectives. Production, reproduction (days open and calving interval) and pedigree data of Iranian Holstein dairy cattles were collected between 2002 and 2012 from 47 herds in Isfahan province. The data set consisted of 30179 records from 18837 registered IranianHolstein dairy cattles. Single trait r...

The present study was conducted to assess the degree of genetic determination of the variability in the mean nocturnal plasma concentration of melatonin in sheep. Three hundred twelve ewes born from 18 males and with known genealogy were sampled at the summer and the winter solstices. The nocturnal plasma melatonin concentration was defined as the mean of four plasma samples taken at hourly int...