Research On Animal Production

     The study of milk production and composition curves in buffalo provides key pieces of information about genetic potentials and management-related strategy to both breeders and farmers. The objective of this study was to identify of the non-genetic factors of parameters for fitted Wood function on milk fat content (MFC) and milk fat percentage (MFP) curve of Azari and Khuzestan buffalo. The data were collected from 15065 and 15225 from Khozatani buffalo and 9571 and 9721 lactation period of Azari buffalo on MFC and MFP were used for further analyses. For the first phase, the Wood function for each individual within the investigated population was fitted. Then, environmental factors affected MFC and MFP in both populations were assessed. In the last step, after the estimation of curve parameters, the phenotypic correlation for both populations was estimated. Results of the present study showed the MFP of Khuzestan breed was almost % 0.5 lower than Azari breed and faster reached to the lowest point within MFP curve shape. Furthermore, because of the higher milk production rate of Khuzestan breed, the MFC of this breed showed almost % 25 higher at the peak,  compared to the Azari buffalo. Also, due to higher observation of daily milk production in Khuzestan buffalo, this breed has good potential to produce more daily MFC and less MFP than Azari. Finally, the outputs of the report this research may be effective in help to improving nutritional the feeding formulation and genetics programs of Iranian buffaloes.

    In the present study, phenotypic data including the live bodyweights and the growth rate characteristics of broiler chickens were collected from two offspring generation of 47 and 71 sires of a Commercial Broiler Line respectively and then were separately entered for estimation heritability and statistical calculating the correlation of growth-related traits under conditions routine breeding were used under inducible cold stress for ascites syndrome. Later on, the estimation of heritability for growth related traits was done using UNIVARIATE analyzes and calculation of genetic and phenotypic correlations of these traits with MULTYVARIATE analysis using AREML procedure of WOMBAT software. The heritabilities of growth-related traits varied from low to high in two routine and inducible cold stress condition (from 0.08 to 0.76(and most of it was generally early in the growth period and showed a decreasing trend with age, similar trends were observed in the results in both generations. Phenotypic correlations were lower than genetic correlations at all weeks. With increasing age, genetic and phenotypic correlations for all traits showed a decreasing trend. These results suggest that in addition to the greater influence of non-genetic factors in reducing the share of incremental genetic variance of the total variance, the occurrence of ascites in the last few weeks (especially in cold stress conditions) has reduced the heritability of growth-related traits. The observation of the present report indicated there is no high significant genetic correlation between growth-associated traits between routine temperature conditions and under cold-inducible stress existed, this phenomenon makes messages and conclusion responsible candidate gene for both conditions could not be the same. Outputs about moderate to high estimates for the heritability of the investigated traits indicate that genetic selection can lead to an improvement in such growth characteristics.

Historically, both significant decline of genetic diversity and simultaneously increasingly rate of inbreeding are two serious threaded factors in worldwide dairy industry. With this motivation, the aim of present report was to investigate the intra genetic diversity criteria (linkage disequribrium, observed and expected heterozygosity, F_is statistics, MAF distribution, autozygosity rate and population stratification using principal component analysis) in Holstein cattle population using dense markers. An Illumina Bovine 50k SNP Chip (V2) ready genotyped file for 25 Holstein cows obtained for further investigation. Here, we used Plink software for statistical analysis and measurement of molecular diversity indices. Observed outcomes results addressed average of MAF (0.28), mean frequency of observed and expected heterozygosity (0.38, 0.37), F_is statistic (– 0.032), F_hom statistic (-0.028-0328. In addition, PCA graph showed a significant indicating high population diversity, which was in accordance with all other calculated parameters. As a final conclusion, high-density SNP markers seems be as an accurate tool applicable for high-precision intra-diversity analyses.

Extended Abstract
Introduction and Objective: To date, sex determination technique in domestic animal has economic benefits. Recently, circulating free DNA (cfDNA) highlighted as suitable candidate for non-invasive sex determination in livestock and endangered wild life animals. Based on this motivation, the objective of this report was the potential usefulness of free fetal DNA in maternal blood for prenatal fetal gender determination in pregnant goats.
Material and Methods:  In this respect, a total of 21 animals, including 17 pregnant females with a gestation period of six weeks, unborn goats and 2 males (negative controls) were selected. During the running experiment, estrous synchronization  was performed by intravaginal CIDR. The animals not returned to estrus was considered as an indicator of success in pregnancy. Also in the last months, ultrasound method was used to confirm pregnancy. In the next phase, cffDNA was extracted from the blood plasma of female goats using the available common experimental protocol. The primers in this experiment were designed based on AME gene located on X and Y chromosomes. The polymerase chain reaction was optimized based on available standard methods.
Results: The observation addressed existence of two fragment in the male embryo (171 bp AMELX gene band and 111 bp AMELY gene band) and one fragment in the female embryo (171 bp AMELX gene band). Here, most of findings was in line of similar pervious literatures and sex determination based on AME gene in case of sensitivity, specificity and accuracy indices indicated 0.83, 0.93 and 0.93 respectively.
Conclusion: On this basis, the results opened a new horizon of the potential usefulness of free fetal DNA in maternal blood for prenatal fetal gender determination in pregnant goats.

Extended Abstract
Introduction and Objective: Varroa infestation is undoubtedly the greatest threat and challenge facing Apiculture today. This external parasite inevitably lives in the bee colony and causes irreparable damage to its colony and the subsequent honey production. One of the proposed strategies in this regard is the use of pesticides, which have a negative impact on the health of bees and honey consumers. To avoid these negative consequences, safer alternative methods of controlling mites are needed, including the use of resistant genetic strains and breeding selection programs to establish colonies with relative resistance to mites. In honeybee colonies, there are several physiological and behavioral mechanisms for Varroa resistance that by examining their relationship with identified resistance genes, the genetic basis of Varroa mite resistance in honeybees is identified and can used in breeding programs. The aim of the present study was to identify single nucleotide polymorphisms (SNPs), in a sample of the Iranian honeybee population, in the candidate gene (the dopamine receptor gene (DOP3)) effective on defense behaviors of honeybees against the varroa mite.
Material and Methods: For this purpose, a total of 10 drone bees (5 susceptible and 5 resistant) were selected and their DNA was then isolated using a CTAB-based method. The PCR was carried out based on specific primers in the UTR region sequence of the DOP3 gene. The quantity and quality were then determined using the nanometer method. After a single band (900 bp) of the expected size, product purification and sequencing (Sanger method) were performed. The display of the outputs and the determination of the quality of the raw sequence (phred index) took place with the FinchTV software and the alignment with BLAST and clustering with the MAFTT software.
Results: In this study, differences were observed in several regions of the nucleotide sequence of the UTR region of DOP3 gene, the most important difference in the nucleotide sequence between sensitive and resistant individuals in the two regions. One is in the nucleotide region of 428 to 437 forward readings as many as 9 bp nucleotides and the other is in the nucleotide region of 715 to 720 forward readings as many as 6 bp nucleotides, which in both, mutations of the deletion type have been performed.
Conclusion: Evaluation of the final results showed significant difference, in type of deletion/addition with the size of 6 and 9 bp between two groups (sensitive and resistant to Varroa), respectively which can be used in the molecular identification of resistant colonies and breeding programs to produce Varroa mite resistant colonies. No such deletions from this gene have been reported so far.

 

Extended Abstract
Background: To date, one of the main areas of research is the creation of breeds with inherent resistance to digestive nematodes in sheep. In this context, resistance to digestive nematodes has exhibited significant phenotypic differences within and between sheep breeds, suggesting a genetic basis for these differences. According to the list of effective candidate genes and the identified gene network for parasite resistance in sheep, there are genes involved in the immune system, such as the interferon-γ gene (IFN-γ). Cytokinin is involved in biochemical immune system signaling pathways, parasite resistance, and immunological responses. In addition, certain mutations in this gene impair the ability of specialized cells of the immune system to fight off parasite invasion. One of the most popular approaches to generating gene expression data for genome function studies is DNA microarray technology, which allows the simultaneous expression of thousands of genes. Proteomics and genomics are two application areas of microarray technology. This research aims to identify and categorize some of the genes involved in the relative genetic resistance of sheep to nematode infection using microarray data.
Methods: In this context, the GEO-Bank, part of the NCBI, was searched for access to open-access databases. Downloaded microarray data corresponded to infection with parasitic nematodes with the best replication (e.g., data in two resistant and sensitive groups), and the set of genes with differential expression was identified using R -based appropriate software packages (Biobase, GEOquery, limma, affy, Genfilter, Pheatmap, Plyr, Reshape2, and Ggplot2). Raw data were measured on a logarithmic scale, and the P-value fit statistics were used for expression comparisons between gene groups.
Results: The main analysis was performed after precorrection and processing of the raw data because of the high intragroup variance of the data, as evidenced by the observed quality control results of the raw data and the quality control-related results of the integrated data. After pre-processing of the raw data, correlation analysis revealed a strong relationship between genes in the pre-Inf group (Pre-Inf) and the infected group (Inf) compared to the control group. Three heatmap reference charts, a PCA chart, and a volcano plot were used to verify data quality, and by verifying these charts, samples of unfavorable quality were removed from the next stages of analysis. After a bioinformatics analysis, the results showed significantly increased expression patterns (NACA, RPL4, NAGS, CTCF, GBP1, BHLHE, YTHDF3, PDHA1, and MXI1) and diminished expression patterns of PDHA1 and MXI1 genes. According to the results of this study, these genes play a role in the cellular metabolism process, molecular function, the formation of genetic connections, and cell life. Therefore, they were significant (p-value < 0.05) according to the magnitude of the change. The N-acryl glutamate synthetase (NAGS) gene is the cofactor of the first enzyme involved in the urea cycle in mammals. The functional role of this gene has been identified in many neurological diseases. The CTCF gene has a positive effect on the cells of the immune system and plays a special role in defending against viruses and pathogens that invade the host body. The guanylate binding protein 1 (GBP1) gene plays a role in the body's defense against many infectious pathogens. This gene causes oxidative reactions and autophagy of the host immune system as a barrier to invading pathogens. The methyl adenosine RNA binding 3 gene is more effective in antiviral immunity and is closely linked to the GBP1 gene, which plays a role in the body's resistance to many infectious agents. This gene causes oxidative responses and autophagy of the host immune system against invading pathogens. The PDHA1 pyruvate dehydrogenase gene is involved in immune system metabolism. This gene plays a role in allosteric factor-induced regulation, repair of covalent bonds, and relatively rapid changes in the level of expressed proteins, either through altered gene expression or proteolytic degradation. The MXI1 gene helps control the entry of invading pathogens into the host's body and promotes recovery and healing from infections. The results can be explained by several reasons, including the use of different sample breeds and laboratory techniques, the level of parasite contamination, the age of the test material, the variety of tested nematodes, and inconsistent techniques and tools of the current study with those of previous studies. Other reasons include the climatic differences between the test region and its physical location as well as the use of different RNA and microarray methods. However, the results of the study may be helpful under the related circumstances.
Conclusion: The results of microarrays and differential expression patterns can be of great help to molecularly modify livestock to resist internal parasites. Using more advanced tools, such as next-gene sequencing, will provide more accurate and relevant information.