The current state of the problem of in vitrogene pool preservation in poultry

This review presents the current progress in and approaches to in vitroconservation of reproductive cells of animals, including birds, such as cryopreservation and freeze-drying, as well as epigenetic conditions for re storing viable spermatozoa and female gametes after conservation. Cryopreservation is an effective way to preserve reproductive cells of various species of animals and birds. In vitrogene pool conservation is aimed primarily to the restoration of extinct breeds and populations and to the support of genetic diversity in populations prone to genetic drift. It is the combination of ex situ in vivoand ex situ in vitromethods that can form the basic principles of the strategy of animal genetic diversity preservation. Also, use of cryopreserved semen allows faster breeding in industrial poultry farming. Despite numerous advances in semen cryobiology, new methods that can more efficiently restore semen fertility after cryopreservation are being sought. The mechanisms underlying the effect of cryopreservation on the semen parameters of cocks are insufficiently understood. The review reflects the results of recent research in the field of cryopreservation of female and male germ cells, embryonic cells, the search for new ways in the field of genetic diversity in vitro (the development of new cryoprotective media and new conservation technologies: freeze-drying). Molecular aspects of cryopreservation and the mechanisms of cryopreservation influence on the epigenetic state of cells are highlighted. Data on the results of studies in the field of male reproductive cell lyophilization are presented. The freeze-drying of reproductive cells, as a technology for cheaper access to the genetic material of wild and domestic animals, compared to cryopreservation, attracts the attention of scientists in Japan, Israel, Egypt, Spain, and France. There is growing interest in the use of lyophilized semen in genetic engineering technologies. Methods of freeze-drying are developed taking into account the species of birds. Organizational and legal ways of solving the problems of in vitroconservation of genetic resources of farm animals, including birds, are proposed

Hepcidin as a Regulator of Iron Metabolism and Mediator of Inflammation in Patients with Chronic Heart Failure and Anemia of Chronic Diseases of the Elderly and Senile Age

Aim. To study the role of hepcidin as a regulator of iron metabolism and a mediator of inflammation in elderly and senile patients with chronic heart failure (CHF) with anemia of chronic diseases (ACD).Material and methods. The levels of hemogram parameters, ferrokinetics (serum iron, ferritin, transferrin, erythropoietin, hepcidin), inflammation [C-reactive protein (CRP), interleukin-6 (IL-6)], as well as correlations between hepcidin and these parameters were studied in patients with CHF with ACD (n=35), with CHF without anemia (n=35) and in elderly and senile patients without CHF and anemia (control group; n=20).Results. Normal levels of hepcidin (9.17±0.97 ng/ml) and the only significant correlation of hepcidin with the ferrokinetic parameter – serum iron [r(S)=0.480, p<0.05] were found in the control group. Normal levels of hepcidin (12.01±1.19 ng/ml) and two significant correlations of hepcidin with the ferrokinetic parameter – ferritin [r(S)=0.525, p<0.05] and transferrin [r(S)=-0.343, p<0.05] were found in the CHF without anemia group. Significantly elevated levels of hepcidin (23.81±3.63 ng/ml) were found in the CHF with ACD group compared to the CHF without anemia group (p=0.008) and the control group (p=0.003). Also, five significant correlations of hepcidin with hemogram parameters – hemoglobin [r(S)=-0.461, p<0.05] and the average concentration of hemoglobin in the erythrocyte [r(S)=-0.437, p<0.05]; with ferrokinetic parameters – ferritin [r(S)=0.596,p<0.05] and transferrin [r(S)=-0.474, p<0.05]; with inflammation parameters – CRP [r(S)=0.561, p<0.05] were found in the CHF with ACD group.Conclusion. The increased level of hepcidin in CHF patients with ACD and the formation of links of hepcidin with indicators of inflammation reflect its role as a mediator of inflammation, and the formation of connections with indicators of hemogram and ferrokinetics – its role as a regulator of iron metabolism involved in the development of ACD in elderly and senile CHF patients

Genetic variability in local and imported germplasm chicken populations as revealed by analyzing runs of homozygosity

Simple Summary To maintain the uniqueness of conserved chicken populations of local and imported breeds is of great importance. In this study, we genotyped small populations belonging to 14 breeds and 7 crossbreds using an Illumina Chicken 60K SNP (Single Nucleotide Polymorphisms) BeadChip and looked for appropriate methods to characterize their purity/variability. It was not straightforward to identify crossbred individuals, and the best approach was based on calculating the length and number of homozygous regions, or runs of homozygosity (ROH), in the populations studied. The latter enabled most accurate identification of crossbreds and can be served as an effective tool in testing genome-wide purity of chicken breeds. Abstract Preserving breed uniqueness and purity is vitally important in developing conservation/breeding programs for a germplasm collection of rare and endangered chicken breeds. The present study was aimed at analyzing SNP genetic variability of 21 small local and imported purebred and F1 crossbred populations and identifying crossbreeding events via whole-genome evaluation of runs of homozygosity (ROH). The admixture models more efficiently reflected population structure, pinpointing crossbreeding events in the presence of ancestral populations but not in their absence. Multidimensional scaling and FST-based analyses did not discriminate properly between purebred populations and F1 crossbreds, especially when comparing related breeds. When applying the ROH-based approach, more and longer ROHs were revealed in purebred individuals/populations, suggesting this as an effective implement in genome-wide analysis of germplasm breed purity

Haplotype structure and copy number polymorphism of the beta-defensin 7 genes in diverse chicken breeds

Beta-defensins is a family of avian peptides related to the innate immune system. Copy number variation was recently reported for the avian beta-defensin 7 gene (AvBD7) between the highly inbred Leghorn and Fayoumi lines. Here, we examined copy number variants in 35 different chicken breeds and found that 31 of them have at least the same representation of the duplicated AvBD7 allele. We also found haplotypes upstream of the AvBD6 regions that are strongly linked to the AvBD7 duplication. We observed a strong linkage disequilibrium spanning of the upstream region of the AvBD6 gene, with two SNPs being flanking markers to detect duplication of the AvBD7

Genome-wide association studies targeting the yield of extraembryonic fluid and production traits in Russian White chickens

Background: The Russian White is a gene pool breed, registered in 1953 after crossing White Leghorns with local populations and, for 50 years, selected for cold tolerance and high egg production (EL). The breed has great potential in meeting demands of local food producers, commercial farmers and biotechnology sector of specific pathogen-free (SPF) eggs, the former valuing the breed for its egg weight (EW), EL, age at first egg (AFE), body weight (BW), and the latter for its yield of extraembryonic fluid (YEF) in 12.5-day embryos, ratio of extraembryonic fluid to egg weight, and embryo mass. Moreover, its cold tolerance has been presumably associated with day-old chick down colour (DOCDC) white rather than yellow, the genetic basis of these traits being however poorly understood. Results: We undertook genome-wide association studies (GWASs) for eight performance traits using single nucleotide polymorphism (SNP) genotyping of 146 birds and an Illumina 60KBeadChip. Several suggestive associations (p <5.16*10(-5)) were found for YEF, AFE, BW and EW. Moreover, on chromosome 2, an association with the white DOCDC was found where there is an linkage disequilibrium block of SNPs including genes that are responsible not for colour, but for immune resistance. Conclusions: The obtained GWAS data can be used to explore the genetics of immunity and carry out selection for increasing YEF for SPF eggs production.Peer reviewe

Study of the effectiveness of a combination of laser curettage and injections of hyaluronic acid-based gel (experiment on laboratory animals)

Study of the effectiveness of a combination of laser curettage and injections of hyaluronic acid-based gel (experiment on laboratory animals

Participation of UGMU dental students in the faculty's volunteer movement

In 2017, the Happy Smile project was developed at the dental faculty of Ural State Medical University and its active implementation began, during which teachers and students conduct preventive measures in educational institutions shopping centers, and hospitals in the city. Studied the involvement of students in the implementation of this, and identified factors affecting the development of this activit

On the results of the Second Scientific Forum “Genetic Resources of Russia”

The Second Scientific Forum “Genetic Resources of Russia” was held in St. Petersburg, June 26-28, 2023. Thе Forum comprised nine associated scientific conferences and conference schools dedicated to the establishment, formation, conservation, development, studying and utilization of biological (bioresource) collections as well as to the activities of bioresource centers, and a round table entitled “Statutory Legal Regulation and Standards for the Work with Bioresource Collections”. More than 700 researchers representing over a hundred scientific institutions and universities from Russia and other countries participated in the Forum. In total, more than 200 oral presentations were made during those events (including 16 talks at the Forum’s Plenary Session). The participants of the Forum events thoroughly discussed the results of the Federal Scientific and Technical Program for the Development of Genetic Technologies for 2019-2030 associated with the establishment and development of bioresource collections for research in the field of genetic technologies, the prospects for the promotion of this sector, and the regulatory legal framework in the sphere of ensuring conservation and development of biological (bioresource) collections, establishment and functioning of bioresource centers, and their sustainable and rational utilization in scientific research and development activities. The outcome of those discussions is presented in this publication in the form of the Forum’s Resolution. Upon reviewing the results of the Federal Scientific and Technical Program for the Development of Genetic Technologies for 2019-2030 pertaining to the establishment and development of bioresource collections for research in the field of genetic technologies, the Forum recognized them as successful. The Forum approved the draft of the legal act “On Bioresource Centers and Biological (Bioresource) Collections”, which is currently under consideration in the State Duma of the Russian Federation and emphasized the need for its soonest adoption

Risk of sperm disorders and impaired fertility in frozen–thawed bull semen: a genome-wide association study

Simple Summary This study tackles the genetic aspects of the risk of sperm damage and related impaired fertility when handling frozen–thawed bull semen for artificial insemination. To this end, we performed genomic association analysis to identify relevant genetic markers and candidate genes associated with various abnormalities in frozen–thawed Holstein cattle sperm. The results provide important insights into the molecular mechanisms underlying sperm morphology and abnormalities after cryopreservation. Further research is needed to explore causative genetic variants and implement these findings to improve animal reproduction and breeding. Abstract Cryopreservation is a widely used method of semen conservation in animal breeding programs. This process, however, can have a detrimental effect on sperm quality, especially in terms of its morphology. The resultant sperm disorders raise the risk of reduced sperm fertilizing ability, which poses a serious threat to the long-term efficacy of livestock reproduction and breeding. Understanding the genetic factors underlying these effects is critical for maintaining sperm quality during cryopreservation, and for animal fertility in general. In this regard, we performed a genome-wide association study to identify genomic regions associated with various cryopreservation sperm abnormalities in Holstein cattle, using single nucleotide polymorphism (SNP) markers via a high-density genotyping assay. Our analysis revealed a significant association of specific SNPs and candidate genes with absence of acrosomes, damaged cell necks and tails, as well as wrinkled acrosomes and decreased motility of cryopreserved sperm. As a result, we identified candidate genes such as POU6F2, LPCAT4, DPYD, SLC39A12 and CACNB2, as well as microRNAs (bta-mir-137 and bta-mir-2420) that may play a critical role in sperm morphology and disorders. These findings provide crucial information on the molecular mechanisms underlying acrosome integrity, motility, head abnormalities and damaged cell necks and tails of sperm after cryopreservation. Further studies with larger sample sizes, genome-wide coverage and functional validation are needed to explore causal variants in more detail, thereby elucidating the mechanisms mediating these effects. Overall, our results contribute to the understanding of genetic architecture in cryopreserved semen quality and disorders in bulls, laying the foundation for improved animal reproduction and breeding

Assessing the effects of rare alleles and linkage disequilibrium on estimates of genetic diversity in the chicken populations

Phenotypic diversity in poultry has been mainly driven by artificial selection and genetic drift. These led to the adaptation to the environment and the development of specific phenotypic traits of chickens in response to their economic use. This study evaluated genetic diversity within and between Russian breeds and populations using Illumina Chicken 60 K SNP iSelect BeadChip by analysing genetic differences between populations with Hudson's fixation index (FST statistic) and heterozygosity. We estimated the effect of rare alleles and linkage disequilibrium (LD) on these measurements. To assess the effect of LD on the genetic diversity population, we carried out the LD-based pruning (LD < 0.5 and LD < 0.1) for seven chicken populations combined (I) or separately (II). LD pruning was specific for different dataset groups. Because of the noticeably large sample size in the RussianWhite RG population, pruningwas substantial for Dataset I, and FST valueswere only positivewhen LD< 0.1 pruning was applied. For Dataset II, the LD pruning results were confirmed by examining heterozygosity and alleles' frequency distribution. LD between single nucleotide polymorphisms was consistent across the seven chicken populations, except the RussianWhite RG populationwith the smallest r2 values and the largest effective population size. Our findings suggest to study variability in each population LD pruning has to be carried separately not after merging to avoid bias in estimates