Some economically useful signs of the pigs of a Large White breed in OOO “Rossyia”

The researches were carried out in ООО “Rossyia” of the Mozhginsky district of the Udmurt Republic. The object of the research was the sows of the main herd of a Large White pig breed. The reproductive qualities of the sows were studied according to such indicators as: the multiple births, the milkness, the mass of a nest in 2 months. The study of reproductive qualities was carried out using breeding cards of the sows and a book for registering farrowing and offspring of the pigs. The evaluation of the reproductive qualities of sows was carried out by calculating the indicators of a variational statistics: the arithmetic mean, the mean quadrate deviation, the coefficients of the variation, the heritability, the correlation. The indicator of a variational statistics was calculated according to the method of N.A. Plokhinsky. The reliability of the coefficients of the heritability and the correlation was determined using Student's t-test. Then studying the reproductive qualities of the sows of the main herd it was established that the multiple births in the average was 10.61 heads, the milkness — 51.34 kg, and the mass of a nest in 2 months — 156.72 kg. Hereat the coefficient of the variability on the multiple births was 12.95%, on the milkness — 8.41%, and on the mass of a nest in 2 months — 10.02%. The coefficient of heritability on the multiple births was 15.00%, on the milkness — 20.00%, and on the mass of a nest in 2 months — 25.00% (P > 0.999). The coefficients of the correlation between the multiple births and the milkness and the multiple births and the mass of a nest in 2 months, respectively, were r = +0.769 and r = + 0.474, and the coefficient of the correlation between the milkness and the mass of a nest in 2 months — r = + 0.754 under the probability of the infallible prognoses P > 0.999.

TO THE ULTRASTRUCTURAL ORGANIZATION OF EPITHELIOCYTES OF EXOCRINE GLANDS

Pieces of the sublingual multi-duct salivary glands of a domestic sexually mature large white pig were fixed in a 4 % paraform solution in 0.1 M phosphate buffer (pH = 7.4) with addi-tional fixation in a 1 % OsO4 solution, dehydrated in alcohols of increasing concentration. Taking into account the recommendations of G. Gayer, pieces of organs were poured into araldite accord-ing to the standard technique. Contrasting was performed according to Reynolds. In the cytoplasm of the mucocytes of the sublingual multi-duct salivary gland, the agranu-lar endoplasmic reticulum predominates, which gives oxyphilic staining. According to electron microscopic studies of mucous glandulocytes in the acini of the sub-lingual salivary glands of domestic pigs, the secretory vacuoles of the cytoplasm are large, with pro-nounced electron-dense membranes. The content of vacuoles in mucocytes of one acinus is differ-ent.

GENETIC ANALYSIS OF UKRAINIAN LARGE WHITE PIG BREED BY POLYMORPHISMS IN RYR1, ESR1 AND PRLR GENES

Marker-Assisted Selection is getting increasing attention in Ukrainian animal breeding as an effective tool for choosing animals with desirable traits. Identification of molecular markers which are related to major genes is a promising approach for improving economic traits and has to be checked for further gene-trait associations. Single nucleotide polymorphisms are genetic markers that can be associated with production traits. SNP genotyping has to be done additionally for each breed to see if they are polymorphic and have significant associations with certain traits. Among the candidate genes that influence the expression of productive traits, special attention is drawn to RYR1, ESR1 and PRLR genes. Gene RYR1 is associated with muscle hypertrophy and other meat quality defects in pigs. ESR1 and PRLR genes influence reproduction and affect the litter size in pigs. SNPs RYR1 g.1843 C>T, ESR1 SNP c.1227 C>T and PRLR g. 1789 G>A have been receiving increasing attention as potential markers for improving quality and pig performance traits. This study investigated the allele variants in three genes (RYR1, ESR1 and PRLR) in Ukrainian Large White pigs of different inside breed types (ULW-1 and ULW-2). The study was performed on 200 pigs. Genotyping was performed using PCR–RFLP method. SNP RYR1 g.1843 C>T was not polymorphic in ULW-1 and ULW-2 inside breed types, when ESR1 SNP c.1227 C> T and PRLR g. 1789 G>A were highly polymorphic. SNPs in ESR1 and PRLR genes had high PIC and χ2 values which indicates the relevance of further associative studies in ULW-1 and ULW-2. Informativeness of the genetic markers in ESR1 and PRLR genes was optimal for associative studies in Ukrainian Large White pig breed of first and second inside breed type.

Фактори, що впливають на мертвонародження поросят у свиноматок великої білої породи

This study considers signs of a sow that affect the stillborn piglets number in the nest and the likelihood of stillbirth. The animals that were used for this study were kept on the pig farm of «Tavriys’ki svyni» LLC, located in the Skadovsky district (Kherson region, Ukraine). The experimental materials used for this study consisted of 100 animals from productive parent sows of the Large White pig. The reproductive indicators of each animal included in this study were evaluated. The total number of piglets at birth (both live and dead), i.e. total litter size and and sow farrowing number were monitored for the first eight farrows during the period of eleven years (2007–2017). Stillborn piglets were observed in 63.3 ± 1.7% of litter, and their average proportion in the nest was 11.5 ± 0.4%. The proportion of piglets born dead of the total piglets at birth obtained in this study is within the range of 5 to 15%, which has been previously noted for commercial pig farms in other countries. With an increase in the age of the sow (the number of farrowing’s), there was a gradual decrease in the proportion of the litter in which no stillborn piglet was observed (χ2 = 51.35; P < 0.001), and, conversely, the proportion of nests in which 2–4 stillborn piglets were recorded gradually increased (χ2 = 46.32; P < 0.001). The number of stillborn piglets and the frequency of stillborn piglets in the litter tended to increase in sows that had a large litter size at birth (in both cases: P < 0.001).The binary logistic regression analyses indicated that the probability of a piglet being stillborn was significantly associated with the farrowing number of the sow and the total number of piglets in the litter (χ2 = 155.00; P < 0.001). This model predicted well the presence of at least one stillborn piglet per litter (in 86.6% of cases) and more or less adequately predicted its absence (in 42.9%). Our results indicate that there is a significant interaction between the number of farrowing and the total size of the litter when determining the estimate of the proportion of stillborn piglets in the litter. The same predicted estimates can be obtained for a small litter in an older sow, or, conversely, for a large litter in a first-farrowing sow.

Mitochondrial DNA Diversity in Large White Pigs in Russia

The Large White pig is the most commonly raised commercial pig breed in the world. The aim of this work was to investigate D-loop mtDNA in Large White pigs (n = 402) of various selections bred in the Russian Federation from 2000 to 2019. The general sample consisted of three groups: Old (n = 78) (Russian selection, 2000–2010); Imp (n = 123) (imported to Russia in 2008–2014); New (n = 201) (2015–2019). The synthesized score (Fz) was calculated by analyzing the main PCA (principal component analysis components). An affiliation to Asian or European haplogroups was determined according to the NCBI (National Center for Biotechnology Information). In the study, we defined 46 polymorphic sites and 42 haplotypes. Significant distinctions between groups Old, Imp and New in frequencies of haplotypes and haplogroups were established. The distribution of Asian and European haplotypes in the groups was Old: 50%/50%, Imp: 43%/57%, New: 75%/25%, respectively. The variety of haplotypes and haplogroups in the pigs of the group New is related to the farms in which they breed. Haplotype frequencies significantly differ between the clusters Old_Center, Old_Siberia and Old_South. This study will provide information on the genetic diversity of Large White breed pigs. The results will be useful for the conservation and sustainable use of these resources.

A 63-bp insertion in exon 2 of the porcine KIF21A gene is associated with arthrogryposis multiplex congenita

SummaryArthrogryposis multiplex congenita (AMC) is a recessively inherited fatal disease detected almost 20 years ago in the Swiss Large White pig population. A diagnostic marker test enabled the identification of carrier animals, but the underlying causal mutation remains unknown. To identify the mutation underlying AMC, we collected whole-genome genotyping and sequencing data for 11 affected piglets and 23 healthy pigs. Haplotype-based case-control association testing using 47,829 SNPs confirmed that AMC maps to SSC5 (P = 9.4 ×10−13). Subsequent autozygosity mapping revealed a common 6.06 Mb region (from 66,757,970 to 72,815,151 bp) of extended homozygosity in 11 piglets affected by AMC. We detected a 63-bp insertion in the second exon of KIF21A gene encoding Kinesin Family Member 21A using whole-genome sequences of a carrier boar, two of its affected and two heterozygous piglets. This insertion was compatible with the recessive inheritance of AMC. The 63-bp insertion likely represents a loss-of-function allele because it is predicted to introduce a premature stop codon in KIF21A gene (p.Val41_Phe42insTer) that truncates 1,614 amino acids (∼ 97%) from the protein. Lack of KIF21A protein is lethal in mice, thus providing additional evidence that a loss-of function allele of KIF21A might cause fatal AMC in pigs. We found that this deleterious allele still segregates at low frequency in the Swiss Large White pig population. The unambiguous detection of carrier animals can now facilitate the eradication of the deleterious allele from the population.