Allowing a single electron to hop to next-nearest neighbours (NNN) in addition to the closest atomic sites in the Holstein model, a modified Trugman method is applied to exactly calculate the effect on the polaronic effective mass in one, two, and three dimensions, building on the previous study of the one-dimensional NNN Holstein model. We also present perturbative calculations and a heuristic...

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...

Beef derived from Holstein steers is a significant source of the U.S. beef supply. The nation’s 9.1 million dairy cows in 2003 were 22% of the U.S. cow herd (NASS, 2005). Given the typical breed distribution of dairy cows, calving interval, full-term pregnancy rate, peri-natal calf death loss (NAHMS, 2002), gender distribution, dairy beef placement (80%) and survival to market (94%), it can be ...

Complex vertebral malformation (CVM) is a recently described monogenic autosomal recessive hereditary defect of Holstein dairy cattle that causes premature birth, aborted fetuses and stillborn calves. Guanine is substituted by thymine (G>T) in the solute carrier family 35 member A3 gene (SLC35A3). A valine is changed to a phenylalanine at position 180 of uridine 5'-diphosphate-N-acetyl-glu...

This investigation was conducted to identify polymorphism of the leptin gene in Holstein cows, Mazandarani native cattle and buffaloes by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). The frequencies of A and B alleles were 0.4 and 0. 6 in Holstein cows, 0.56 and 0.44 in Mazandarani native cattle, 0.61 and 0.35 in buffaloes, respectively. The heterozygote genoty...

a pedigree file of 382831 holstein cows and bulls, collected from herds registered by animal breeding center of iran during 1967 to 1999, was used to calculate the inbreeding coefficient. the mean inbreeding coefficient for the whole population (male and female), on a base year of 1946, was 0.184%. the means for cows (94 percent of the whole population) and bulls (6 percent of the whole populat...

Intake and annual performance of Limousin × Holstein-Friesian and Simmental × Holstein-Friesian beef suckler cows, and pre-weaning growth of their calves Beef cross dairy heifers remain a significant source of replacement breeding stock for the suckler herd in Ireland. Previous studies at this centre have compared Hereford × Friesian beef suckler dams with Charolais × Friesian and Limousin × Fr...

The objective of present study was to derive the economic values for number of inseminations to conception, calving interval, milk yield and stillbirth, using economic data of 10 Iranian Holstein herds. The economic values were derived by using the profit function methods and differentiating a profit equation with respect to the traits of interest. The cow fertility costs herd amortization or r...

quantitative traits locus for milk production traits has been described on centromeric end of bovine chromosome 14. reports name the acyl coa: diacylglycerol acyltransferase (dgat1) gene as a potential candidate gene with dinucleotide substitution (aa to gc) in exon viii which causes the change of lysine to alanine in amino acid (k232a).the aim of the present study was to estimate the frequency...

this experiment was aimed to study the association between the dgat1 k232a polymorphism and milk production traits and somatic cell score (scs) in iranian holstein dairy cows. the records of 408 animals from five dairy herds were randomly identified and then genomic dna was extracted from blood using the modified-salting method described by miller. rflp-pcr was performed to obtain all the polym...