Male calves and culled cows of dairy cattle are used for beef production. However, unlike beef breeds, the genetics of growth performance traits in dairy breeds have not been extensively studied. Here, we performed a genome-wide association study (GWAS) on Holsteins ( = 5,519), Jerseys ( = 1,231), and Red Dairy Cattle ( = 4,410) to identify QTL for growth traits. First, a GWAS was performed wit...

the influence of melatonin receptor 1a gene on litter size was studied in 150 ewes from zel (n=100) and naeini (n=50) sheep breeds. two restriction fragment length polymorphism (rflp) analyses were done to determine all genotypes occurring by variations at mnli and rsai restriction sites. the m and c were the most frequent alleles in both of these breeds. the mm genotype was predominant in zel ...

Selection during the last decades has split some established dog breeds into morphologically and behaviourally divergent types. These breed splits are interesting models for behaviour genetics since selection has often been for few and well-defined behavioural traits. The aim of this study was to explore behavioural differences between selection lines in golden and Labrador retriever, in both o...

Dogs (Canis familiaris) were domesticated from the gray wolf (Canis lupus) at least 14,000 years ago, and there is evidence of dogs with phenotypes similar to those in modern breeds 4000 years ago. However, recent genetic analyses have suggested that modern dog breeds have a much more recent origin, probably <200 years ago. To study the origin of contemporaneous breeds we combined the analysis ...

Selective breeding of dogs by humans has generated extraordinary diversity in body size. A number of multibreed analyses have been undertaken to identify the genetic basis of this diversity. We analyzed four loci discovered in a previous genome-wide association study that used 60,968 SNPs to identify size-associated genomic intervals, which were too large to assign causative roles to genes. Fir...

In order to protect the genetic resource of native horse breeds, the genetic diversity of mitochondrial DNA (mtDNA) D-loop of three native horse breeds in western China were investigated. Forty-three 600 bp mtDNA D-loop sequences were analyzed by PCR and sequencing techniques, 33 unique haplotypes with 70 polymorphic sites were detected in these horses, which account for 11.67% of 600 bp sequen...

The Brazilian cattle population is mainly composed of breeds of zebuine origin and their American derivatives. Comprehensive knowledge about the genetic diversity of these populations is fundamental for animal breeding programs and the conservation of genetic resources. This study aimed to assess the phylogenetic relationships, levels of genetic diversity, and patterns of taurine/zebuine admixt...

Due to its geo-climatic conditions, Algeria represents a biodiversity hotspot, with sheep breeds well adapted to a patchwork of extremely heterogeneous harsh habitats. The importance of this peculiar genetic reservoir increases as climate change drives the demand for new adaptations. However, the expansion of a single breed (Ouled-Djellal) which occurred in the last decades has generated a crit...

9 Dog agility is a rapidly progressing sport worldwide. Consequentially, research and methods 10 to improve technique and performance are becoming highly sought after. Video data were 11 collected of elite agility dogs during a training session, with downstream analysis examining 12 differences in apparent topline angle and jumping speed of large and medium dogs as well as 13 collie breeds and ...

Performance of Dorper sheep was compared to other breeds in pure and cross-breeding evaluations under different production systems. The number of ewes lambed per ewe joint (E(L)/E(J)) varied for the Dorper from 0.68 to 0.91 (average 0.81) and for other breeds and crosses from 0.65 to 0.91 (average 0.82). Average litter size (L(B)/lambing) varied from 1.02 to 1.52 (average 1.28) and from 1.02 to...