POU1F1 is a positive regulator for GH, PRL and TSHβ and its mutations associate with production traits in ruminant animals. We described a DdeI PCR-RFLP method for detecting a silent allele in the goat POU1F1 gene: TCT (241Ser)>TCG (241Ser). Frequencies of D1 allele varied from 0.600 to 1.000 in Chinese 801 goats. Significant associations of DdeI polymorphism with production traits were found i...

The present study was undertaken to confirm and refine the mapping of a quantitative trait locus in cattle for milk fat percentage that had earlier been reported to be linked to the serum amylase-1 locus, AM1. Five half-sib families from the previous study and 7 new ones were genotyped for nine microsatellite markers spanning chromosome 4. AM1 was mapped between the microsatellite markers BMS64...

The objective of this research was to partition phenotypic variation in calf gain from birth to weaning, and milk production measured, by the weigh-suckle-weigh method, and udder score of cows into genetic and nongenetic components. Data were from the Line 1 Hereford population maintained by USDA-ARS at Miles City, MT, and included observations of pre-weaning gain (n = 6,835) from 2,172 dams, m...

A genome wide association study was conducted using estimated breeding value (EBV) for milk production traits from 1st to 4th lactation. Significant single nucleotide polymorphism (SNP) markers were selected for each trait and the differences were compared by lactation. DNA samples were taken from 456 animals with EBV which are Holstein proven bulls whose semen is being sold or the daughters of...

Quantitative trait loci affecting conformational type traits were studied in seven large grandsire families of US Holsteins using the granddaughter design and 16 microsatellite markers on 10 chromosomes. The most significant marker effect was marker BM203 (chromosome 27) for dairy form in a single grandsire family. A multivariate analysis for dairy form and milk yield was also conducted, and th...

dairy cattle breeding programs have been based in the selection for traits related to milk production. in this research a data set of 63 herds of east azerbaijan province holstein cattle, collected during 2002-2013 by the iranian animal breeding center was used to estimate the repeatability and heritability of three traits of economic importance. genetic parameters for first three lactations of...

Quadratic milk pricing formulas based on total yield with concentration differentials for fat and protein can be linearized to price milk based on yields of carrier, fat, and protein. Selection responses for a quadratic milk revenue function and an equivalent linear milk revenue function were compared in each case using in the selection indices those waits in the corresponding milk revenue func...

Characteristic of the udder, milk traits and their relationship were investigated in 32 Awassi ewes raised in a commercial flock. Commencing one month after lambing milk yield was recorded at monthly intervals until the ewes were dried. Also, the udder traits were measured, including udder width, udder circumference, udder length, distance between teats and length and diameter of both teats. Re...

Many studies highlighted potential associations of β-casein A1 with specific human diseases and a minor digestibility milk, due to the bioactive peptide β-casomorphin 7 (BCM-7) release during digestion. Conversely, ancestral A2 variant seems be favorable trait because it is not associated BMC-7 release. The aim this work was evaluate frequencies variants in offspring previously genotyped cows i...