This was the second study to apply using of a cytochrome b gene as barcoding tool in distinguishing among chicken strains. We performed polymerase chain reaction (PCR) amplification using universal primer to amplify around 415 bp fragment of cytochrome b gene of mtDNA. The tree reported that both Saudi chicken strains (black and dark brown) are closely related and it might be separated from same origin rather than bronze ones. The phylogenetic tree also, exploited that native chicken strains were closely related to cluster of Ceylon jungle fowl, black Minorca egg chicken and Fayoumi egg chicken. The genetic divergence between these populations or types of chickens in Saudi Arabia was low (0.02) and it was very low (0.011), when compared to other species of Gallus. We confirmed that short fragment of cyt-b gene as a universal DNA barcode region. It was much more accurate and efficient tool to discriminate inter-species than intra-species. Applying cyt-b of mtDNA was successfully distinguished among native strains and other species of Gallus as in a previous study. However, applying this thought on different species of farm animal species is recommended.

β-Lactoglobulin (β-LG) is the dominant non-casein whey protein found in milk of bovine and of most ruminants. The amino acid sequence of β-LG along with its 3-dimensional structure illustrates linkage with the lipocalin superfamily. Preliminary studies in goats indicated that milk yield can be influenced by polymorphism in genes coding for whey proteins. The aim of this study is to identify and evaluate the incidence of functional polymorphisms in the exonic and intronic portions of β-LG gene in native Saudi goat breeds (Ardi, Habsi and Harri). Blood samples were collected from 300 animals (100 for each breed) and genomic DNA was extracted using QIAamp DNA extraction kit. A fragment of the β-LG gene from exon 7 to 3' flanking region was amplified with pairs of specific primers. Subsequent digestion with Sac II restriction endonuclease revealed two alleles (A and B) and three different banding patterns or genotypes, i.e. AA, AB, and BB. The statistical analysis showed that β-LG AA genotype had higher milk yield than β-LG AB and β-LG BB genotypes. Nucleotide sequencing of the selected β-LG fragments was done and submitted to GenBank NCBI (Accession Nos. KJ544248, KJ588275, KJ588276, KJ783455, KJ783456, KJ874959, and KP269078). Two already established SNPs in exon 7 (+4601 and +4603) and one fresh SNP in the 3' UTR region were detected in the β-LG fragments with designated AA genotype. The exonic SNPs, i.e. +4601 (G/A) and +4603 (G/C), were found within the Sac II restriction site and accountable for generating the AA genotypic patterns. Hence, the allele characterized by the substitution G>A has been sub-designated as AA A , while the one characterized by the substitution G>C as AA C . The polymorphisms in exon 7 did not produce any amino acid substitution.

This study was conducted to find out the fraud in chicken-processed meat ingredients to protect consumers from commercial adulteration and authentication through a reliable way: direct amplification of conserved segment of cytochrome b gene of mitochondrial DNA, in addition, using species-specific primer assay for a certain cytochrome b. The results reported that chicken-processed meats were identified as a chicken meat based on amplification of conserved cytochrome b gene of mtDNA, while different fragments sizes were produced after the application of species-specific primer as follows: 227, 157, 274, 331, 389 and 439 bp for raw meat of chicken, goat, cattle, sheep, pig and horse, respectively. The results revealed that all chicken meat products are produced with 227 bp in size. While, an adulteration with pork stuffs was observed in some of the chicken meat products using a species-specific primer of cytochrome b gene, namely, chicken luncheon and chicken burger. This study represents a reliable technique that could be used to provide a promising solution for identifying the commercial adulteration and substitutions in processed meat in retail markets.

The current study was carried out to investigate and estimate the genetic diversity of native breeds based on cytochrome b (cyt-b) gene of mitochondrial DNA information. The obtained sequences of cyt-b gene segment have TAA as a stop codon at 488 position with no insertions or deletion in all individuals of both native chicken strains. The blast results showed that no variation was found among individuals within both native chicken strains, but when a comparison was established among them and other species of genus Gallus the variation is exploring, additionally many mutant sites were detected as single nucleotide polymorphisms (SNPs) in different sites. The phylogenetic trees exhibited three different groups. The results revealed that the native chicken strains were closely related to the cluster of Gallus gallus and subspecies of Gallus, suggesting that they may be separated from the same origin. According to this result and previously studies, the native chicken strains are genetically closer to Gallus gallus and it could be successfully distinguished from the other wild types of Gallus chicken based on cyt-b gene information. We recommended that the governmental concerns for native chicken strain should be enhanced to screen its genetic structure for large scale in the Kingdom of Saudi Arabia.

No abstract