BACKGROUND: Major histocompatibility complex (MHC) encodes for highly variable molecules, most of which are responsible for foreign antigen recognition and activation of immune responses in the host. LEI0258 microsatellite, located in the poultry MHC region, is a suitable genetic marker for determining MHC haplotypes and genetic diversity in poultry.OBJECTIVES: Considering the fact that there is no report on the frequency and types of MHC alleles and population genetic analysis in Ross 308 poultry in Iran, the present study aimed to investigate the diversity of MHC haplotypes of Ross 308 broilers by LEI0258 microsatellite.METHODS: A total of 216 blood samples were collected from two productive herds of Ross 308 broilers. After extracting DNA of the blood samples and amplifying LEI0258 microsatellite alleles, genotyping of MHC haplotypes was performed using agarose gel electrophoresis and fragment analysis techniques.RESULTS: A total of seven alleles and 21 genotypes were identified for LEI0258 microsatellite in these two groups. the highest and the lowest frequencies belonged respectively to allele 385 bp (42.86 %) and allele 300 bp (4.33 %). Heterozygous 207/385 was found to be the dominant genotype in both populations. According to the similarity matrix analysis, there was an 84.56 % similarity between the two groups.CONCLUSIONS: The results obtained in this study revealed a high level of heterozygosity (85.71 % and 91.35 %) and deviation from Hardy–Weinberg equilibrium (P<0.0001) in these two Ross populations. Ross 308 broiler chickens had lower allelic diversity and higher genetic similarity compared to the native ones. These findings provided additional information on the use of MHC as a candidate gene marker in genetic improvement and resource conservation in broiler populations.

BACKGROUND: Chicken major histocompatibility complex region (MHC) is important in the productive traits, immune responses, resistance to infectious diseases and phylogenetic relationships. OBJECTIVES: This study was investigated for single nucleotide polymorphisms of MHC region related to the immune system in commercial broiler and layer chickens. METHODS: One hundred blood samples were taken from commercial broiler and layer chickens and genomic DNA was extracted by salting out method. The allelic polymorphisms were investigated in B-L, B-F and B-G loci using PCR-RFLP and MspI enzyme. RESULTS: For two commercial broiler and laying populations, in the 374 bp locus of B-L, only BB genotype was detected but in the 1048 bp locus of B-F, two genotypes of CG and GG were identified in broiler chickens. The C allele contained four bands of 515, 410, 75 and 47 bp, and the G allele with five bands of 410, 302, 213, 75 and 47 bp. In B-G (401 bp) locus, three genotypes of MM, MN and NN and two alleles of M with one band (401 bp) and N with two bands (350 and 51 bp) were identified. In total populations, the Shannon information index was calculated to be 0.45 and 0.73 in markers loci of B-F and B-G, and the fixation index values were -0.20 and 0.34, respectively. The highest observed heterozygosity index for B-F and B-G loci was 0.34 and 0.23, respectively. CONCLUSIONS: Considering the confirmation of the presence of polymorphism in two loci of the B-F (in commercial broiler population) and B-G (in commercial broiler and layer populations), these sites can be used as genetic marker in breeding programs to increase resistance to diseases.

BACKGROUND: Major histocompatibility complex (MHC) comprises a group of genes, which plays a central role in immune response. The exon 2 of BuLA-DRB3 is part of the MHC class II in buffalo that highly polymorphic, found to be associated with resistance/susceptibility to infections and also with production parameters. OBJECTIVES: The purpose of the present study is to identify BuLA-DRB3 polymorphism in Khuzestan buffaloes and compare this population with other Iranian and world buffalo populations. METHODS: Blood samples were taken from 136 unrelated Khuzestan river buffaloes. After DNA extraction, second exon of BuLA-DRB3 was amplified by the seminested PCR method. Then, the fragments produced by amplifying second exon were cut by RsaI restriction enzyme according to van Eijik method. In the following, allelic frequencies, genotype frequencies, expected and observed homozygosty and heterozygosity were calculated. RESULTS: In restriction fragment analysis 13 and 24 different allelic and genotype patterns were identified for RsaI restriction enzyme, respectively. 10 out of 13 alleles were previously reported. The most frequent genotype was oo)0.1691) and then followed by hh (0.1544) ,ll(0.1103), lw (0.0955), lh (0,0808), ha (0.0661) and lo (0.0514). Also four most frequent alleles were o (0.2721), h (0.2316),l (0.2316)and w (0.1176), respectively. These seven genotypes and four alleles form 72.76% and74.29% overall genotype and allele frequency of population.  In addition, estimation of heterozygosity/homozygosty and deviation from Hardy-Weinberg equilibriumofcorresponding population revealed observed homozygosty is more than heterozygosity and departure of population from Hardy-Weinberg equilibrium. CONCLUSIONS: The results indicated that exon 2 of the BuLA-DRB3 gene is highly polymorphic among Khuzestan buffaloes and although, there is differences between buffalo’s genetic polymorphism of distinct world regions, Khuzestan buffaloes’ population is similar to Egyptian buffaloes’ population.

Objectives: The objective of this study was to perform a comparative analysis of allelic diversity to reveal population-genetic characteristics of animal breeds, namely Shami (SH), Holstein (HLS), and Aberdeen-Angus (A-A). Materials and Methods: The genetic materials of SH breed animals represented by wool with hair follicles were collected from 39 SH heads in Syria. Also, genetic materials of HLS breed of American selection (n = 55, HLS) and bulls and cows of A-A breed bred at breeding enterprises in Russia (n = 30, A-A) were collected. Genetic differences between the cattle groups were studied using 11 microsatellite markers. Results: The cattle breed in Syria was characterized by high genetic diversity, 107 alleles, while the average number of alleles per microsatellite locus was 9.23, which is significantly higher than that in the animals of HLS (6.18) and A-A (5.00). When analyzing the genetic equilibrium for indi¬vidual locus in SH breed, a deviation from equilibrium at four loci was revealed: TGLA227, SPS115, TGLA122, and ETH225; at one locus in HLS breed: SPS115, for A-A breed: at two loci, i.e., TGLA122 and ETH225. When assessing the level of genetic consolidation, a deficiency of heterozygotes was observed in two of the three studied breeds: 4.8% for SH and 8.0% for A-A. A slight excess of heterozygotes was found in the HLS breed at the level of 0.2%. The average comparative measure¬ment of genetic variation in different populations value for 11 loci for all breeds was 0.069, which indicates that 93.1% of the total variability is due to the intra-breed diversity, and only 6.9% is due to the differences between breeds. Conclusion: The analysis of the animals belonging to their breed has shown a 100% genetic con¬solidation and the compliance of individual animals with the respective breeds. The study of genetic distances, adjusted for small samples, revealed the smallest genetic distance between the SH breed and HLS breed, equaling 0.107. The A-A breed, which has its separate origin and has never been imported into the Syrian Arab Republic, adjoins this cluster as an independent branch. Microsatellites can be used as an essential criterion for assessing the population-genetic charac¬teristics of groups of cattle of various breeds (degree of polymorphism, level of heterozygosity, fixation indices, genetic group membership). [J Adv Vet Anim Res 2021; 8(2.000): 339-345]

Objective: As one of the most valuable genetic resources of Ongole beef cattle globally, the Sumba Ongole (SO) cattle population is being studied in this investigation of myostatin (MSTN) gene polymorphism and its association with growth traits. Materials and Methods: Blood samples from 161 SO cattle were collected and analyzed. Deoxyribonucleic acid (DNA) was isolated. The DNA was electrophoresed and extracted, and finally, the annealing temperature was optimized, followed by amplification and sequencing. Next, we used a Basic local alignment search tool to assess the sequencing data. Results: The analysis revealed 22 single nucleotide polymorphisms (SNPs) in the MSTN gene in this region that showed genetic variation. Two SNPs, c.424 G > A, and c.467 G > C, were found to be significantly associated with SO cattle phenotypes of wither height, heart girth, and hip height (p < 0.05) but not with body weight or body length (p > 0.05). Conclusion: As a result of our findings, the MSTN gene polymorphism and its correlation with growth traits in SO cattle may be employed as a candidate marker in SO cattle and other beef cattle breeds. [J Adv Vet Anim Res 2022; 9(4.000): 565-572]

Genomic DNA polymorphisms obtained by restriction fragment-length polymorphism from healthy horses and horses with hereditary multiple exostoses were analyzed. These DNA were digested by 12 restriction enzymes and were hybridized against 6 isotopically labeled oncogene probes. Hybridization was not detected with the viral oncogene, v-ras, which indicated this oncogene was absent in the equine genome. Oncogenes (c-raf-1, c-fes, c-myb, c-myc, and c-sis) were present and had similar hybridization patterns and signal intensities in DNA from healthy horses and horses with hereditary multiple exostoses. Unique and distinct restriction fragment-length polymorphisms were detected with the c-raf-1 probe only in BamHI- and PstI-digested equine DNA.

The undertaken study was planned to investigate the influence of genetic variants of β-lactoglobulin and κ-casein loci on milk composition traits in two autochthonous Arbi and Serti goats raised in Tunisia's continental oasis region. For this purpose, blood and milk from 177 multiparous and unrelated animals were collected and used. Milk samples were analyzed for physical parameters, chemical composition, and mineral concentrations using standard methods. PCR amplification was performed using DNA samples and specific primers targeting exon 7 and 4 of β-lactoglobulin and κ-casein, respectively. To detect genetic variants, amplified products were digested with the restriction enzymes SmaI for β-lactoglobulin and HaeIII for κ-casein. The κ-casein protein had two alleles A and B, as well as two genotypes AA and AB, whereas the β-lactoglobulin showed two alleles C and T, and three genotypes CC, TT, and CT. Allele A of κ-casein occurred at a higher frequency than allele B in Arbi and Serti subpopulations and overall population. The β-lactoglobulin C allele was more common than T allele in Arbi and Serti subpopulations and throughout population. Homozygotes' frequencies were found to be higher than those of heterozygotes in all animals. Genetic polymorphism of β-lactoglobulin has been linked to milk acidity, dry matter, protein, casein, fat, lactose, Ca, P, and k content, with homozygous TT and CC genotypes clearly outperforming CT genotype. The κ-casein locus had a marked influence on the dry matter, protein, casein, and fat components, favoring homozygous AA goats in all traits except fat, which distinguished heterozygous AB goats.

Encephalomyocarditis virus (EMCV) belongs to the genus Cardiovirus within the family Picornaviridae. EMCV has been recognized either as a cause of mortality in young pigs, due to acute myocarditis, or of reproductive failure in sows. An EMCV K3 strain was isolated from the heart and brain in a mummified and aborted swine fetus in 1989. For the molecular characterization of the poly(C)-tract of EMCV Korean isolates, K3 strain, viral RNA was extracted and digested with RNase T1, and analyzed the length of the poly(C)-tract by polyacrylamide gel electrophoresis. The poly(C) regions also were amplified by RT-PCR and sequenced. The present study shows that K3 strain of EMCV had a short polymorphic poly(C) tracts (5 to 30 C's) with sequences consisting of C∧9, C∧10, C∧13, C∧14, C∧16, C∧20, CUC∧11, C∧8UCUC₃UC∧10, C∧9UCUC₃UC∧10, C∧10UCUC₃UC∧10, etc. These polymorphism of poly(C)-tracts of EMCV K3 strain implies the historical information of in vivo and/or in vitro passage.

The duration of the incubation period for scrapie, a fatal transmissible neurodegenerative disorder of sheep and goats, is mainly determined by the Sip gene, which has 2 alleles (sA-susceptible and pA-resistant). A diagnostic test is not available to detect scrapie in live animals. We analyzed genomic DNA extracted from frozen sheep brains collected from Cheviot sheep of the United States that had been inoculated with the SSBP/1 scrapie inoculum. Digestion of the DNA with EcoRI or HindIII followed by the addition of a scrapie-associated fibril protein (PrP)-specific marker probe, yielded fragments of 6.8 (e1) and 4.0 (e3) kb, or 5.0 (h1) and 3.4 (h2) kb, respectively. Fragments e1 and h2 were associated with the histopathologic diagnosis of scrapie, and fragments e3 and h1 were associated with survival. A valine/alanine polymorphism within the PrP coding region that resulted in a BspHI site was further used to determine the genotype of these Cheviot sheep. Digestion of polymerase chain reaction fragments with BspHI resulted in an undigested fragment b- (0.840 kb), digested fragments b+ (0.460 and 0.380 kb), or both types of fragments. Survival time of b+/b+ homozygous sheep was significantly (P < 0.01) shorter (218 +/- 26.0 days) than survival time for b-/b- sheep (> 700 days after inoculation). Results indicated that b+ and b- are markers for the Sip sA and pA alleles, respectively. The intermediate duration of the incubation period for heterozygous sheep (b+/b-; 342.9 +/- 25.3 days) indicated that the Sip sA allele is expressed codominantly to the Sip pA allele.

The Kedah-Kelantan cattle (KK) is an indigenous cattle breed and is mainly kept for meat production in Malaysia. Due to lack of information about polymorphism of growth traits in these cattle, Insulin-like Growth Factor 1 (IGF-1) was chosen to be the candidate gene in this preliminary study. The aim of this study is to investigate the polymorphism of IGF-1 gene in KK and to show that the PCR-RFLP technique can be used as a basis for use as molecular markers in cattle. A total of 46 KK blood samples were collected for DNA extraction performed using a commercial kit. The exon 1 of IGF-1 gene was amplified to produce a 249 bp fragment. The amplified fragments were digested with Eco105I restriction endonuclease and then subjected to electrophoretic separation in Fluorosafe stained 2.5 % agarose gel. The result revealed two alleles, A and B. Threegenotypes were observed: AA, AB and BB. Frequencies were 0.07, 0.13 and 0.80 for AA, AB and BB, respectively. This gives frequencies of 0.13 and 0.87 for A and B alleles. It is concluded that the population is in Hardy-Weinberg disequilibrium (p<0.05). It is possible that this gene has been exposed to selection.