The genetic diversity of the Turkish native chicken breeds Denizli and Gerze was evaluated with 10 microsatellite markers. We genotyped a total of 125 individuals from five subpopulations. Among loci, the mean number of alleles was 7.5, expected heterozygosity (H e ) was 0.665, PIC value was 0.610, and Wright's fixation index was 0.301. H e was higher in the Denizli breed (0.656) than in the Gerze breed (0.475). The PIC values were 0.599 and 0.426 for Denizli and Gerze, respectively. A phylogenetic tree was constructed using genetic distance and the neighbor-joining method. Its topology reflects the general pattern of genetic differentiation among the Denizli and Gerze breeds. The present study suggests that Denizli and Gerze subpopulations have a rich genetic diversity. The information about Denizli and Gerze breeds estimated by microsatellite analysis may also be useful as an initial guide in defining objectives for designing future investigations of genetic variation and developing conservation strategies.

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Abstract. Effect of increasing zinc concentration in the diets of brown parent stock layers on various production and hatchability traits was investigated. After hatching, chicks were allocated to different treatment groups whose diets were formulated to contain graded concentrations 60 (control), 90, 120, 150, 180 and 210 mg zinc (Zn) kg−1 throughout 62 weeks. No effect of increasing zinc concentration on egg production, 5% egg production age, livability and hatchability rate was found (P > 0.05). On the other hand, significant differences were obtained with increase in zinc concentration in egg weight, feed conversion rate and hatchability effciency of the fertile eggs (P < 0.05). The results of the present study suggest that the diets of brown parent stock layers should include 180 mg Zn kg−1 for optimal performance and hatchability traits.

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Wingless-2 (wg-2) is an autosomal recessive mutation in chicken that results in an embryonic lethal condition. Affected individuals exhibit a multisystem syndrome characterized by absent wings, truncated legs, and craniofacial, kidney, and feather malformations. Previously, work focused on phenotype description, establishing the autosomal recessive pattern of Mendelian inheritance and placing the mutation on an inbred genetic background to create the congenic line UCD Wingless-2.331. The research described in this paper employed the complementary tools of breeding, genetics, and genomics to map the chromosomal location of the mutation and successively narrow the size of the region for analysis of the causative element. Specifically, the wg-2 mutation was initially mapped to a 7 Mb region of chromosome 12 using an Illumina 3 K SNP array. Subsequent SNP genotyping and exon sequencing combined with analysis from improved genome assemblies narrowed the region of interest to a maximum size of 227 kb. Within this region, 3 validated and 3 predicted candidate genes are found, and these are described. The wg-2 mutation is a valuable resource to contribute to an improved understanding of the developmental pathways involved in chicken and avian limb development as well as serving as a model for human development, as the resulting syndrome shares features with human congenital disorders.

Utilizing RNA-seq data, 1,574 candidate genes with alternative splicing were previously identified between two chicken lines that differ in Marek's disease (MD) genetic resistance under control and Marek's disease virus infection conditions. After filtering out 1,530 genes with splice variants in the first or last exon, 44 genes were screened for possible exon loss or gain using PCR and gel electrophoresis. Consequently, 7 genes exhibited visually detectable differential expression of splice variants between lines 6 (MD resistant) and 7 (MD susceptible), and the resultant PCR products verified by DNA sequencing. Birds from inbred line 6 have transcripts that preferentially retain an exon compared to line 7 chickens for ITGB2, SGPL1, and COMMD5. Birds from inbred line 7 have alleles that preferentially retain an exon compared to line 6 for MOCS2. CCBL2 exon 1a is absent and ATAD1 exon 2 is truncated by 87 nucleotides in transcripts expressed by line 7 compared to those from line 6. For CHTF18, line 6 transcripts have an indel mutation with 7 additional nucleotides in exon 21 compared to line 7. The current study validates 7 genes with alternatively spliced isomers between the two chicken lines, which helps provide potential underlying mechanisms for the phenotypic differences.

There are several known hereditary diseases in Arabian horses. Many studies have been conducted on molecular diagnostic methods of the mutations that cause these hereditary defects in horses. A five-base deletion in the short arm (ECA9p12) of the equine chromosome 9, starting with codon 9480, which occurs in the catalytic subunit gene of the DNA-dependent protein kinase (DNA-PKcs) results in severe combined immunodeficiency (SCID) hereditary disorder. SCID is an autosomal recessive disorder wherein the immune system of the affected foal is very weak. Purebred Turkish Arabian horses reared in the Eskişehir region have contributed greatly to Turkish Arabian horse breeding and racing. The aim of this study was to detect the SCID mutant allele by using DNA sequencing analysis in Turkish Arabian horses, raised in nine different private farms in Eskişehir. It was determined that none of the horses evaluated in this study carried the SCID mutant allele.

Avian leukosis viruses (ALV) are retroviruses that can induce tumors in chicken. Typically, ALV is controlled through husbandry. However, genetic improvement and/or, selective breeding techniques, offer the unique possibility of true resistance. The tumor virus B (TVB) locus transcribes the cellular receptor that mediates an infection through B, D, and E subgroups of avian leukosis virus. Two single nucleotide polymorphisms (SNPs) at nucleotide positions 172 and 184 of the TVB locus account for the three major alleles, TVB*S1, TVB*S3, and TVB*R. The receptor encoded by TVB*R allele prevents viral entry into the cell of ALVB, ALVD, or ALVE subgroups. In this study, both SNPs at the TVB locus of Turkish native chicken breeds were investigated using a PCR-RFLP technique to detect. In both Gerze and Denizli breeds, the TVB*S1 allele was common and TVB*S3 was rare, respectively. The TVB*R allele was rare in the Gerze population and absent in the Denizli population. Allele frequencies of TVB*S1, TVB*S3, and TVB*R were evaluated as 0.96, 0.02, and 0.02 in Gerze chickens and 0.98, 0.02, and 0.00, in Denizli chickens, respectively. Keywords: Denizli cocks, Gerze fowls, PCR-RFLP, Tumor virus B locus Türkiye Yerli Tavuk Irklarında Tümör Viral B Lokusunun Belirlenmesi ÖzAvian leukosis virusleri (ALV), tavuklarda tümör oluşturan retrovirüslerdir. Tipik olarak, ALV hayvan yetiştirme yöntemleri ile kontrol edilir. Bununla birlikte, genetik gelişme ve/veya selektif ıslah teknikleri, hastalığa direnç için benzersiz olanaklar sunmaktadır. Tümör viral B (TVB) lokusu ALV üç alt grubunun (B, D ve E) viral girişine ortam sağlayan/engelleyen veya aracı olan gruplara özgü yüzey reseptörlerini kodlar. Bu lokusun 172. ve 184. bazlarındaki iki adet tek nükleotit polimorfizmleri TVB*S1, TVB*S3 ve TVB*R allellerini ayırt edilmesine imkan sağlar. TVB*R'nin kodladığı reseptör ALVB, ALVD veya ALVE alt gruplarının hücreye viral girişini engeller. PCR-RFLP yöntemi kullanılarak Türkiye yerli tavuk ırkları olan Denizli ve Gerze tavuklarındaki TVB genotipleri belirlenmiştir. Hem Gerze hem de Denizli ırkında, TVB*S1 alleli yaygın ve TVB*S3 alleli nadir olarak görülmüştür. TVB*R alleli, Gerze popülasyonunda seyrek olarak görülürken Denizli horozu popülasyonlarında tespit edilememiştir. TVB*S1, TVB*S3 ve TVB*R'nin allel frekansları sırasıyla Gerze tavuklarında 0.96, 0.02 ve 0.02, Denizli horozlarında sırasıyla 0.98, 0.02 ve 0.00 olarak hesaplanmıştır.