Abstract. The coat colour of animals is an extremely important trait that affects their behaviour and is decisive for survival in the natural environment. In farm animal breeding, as a result of the selection of a certain coat colour type, animals are characterized by a much greater variety of coat types. This makes them an appropriate model in research in this field. A very important aspect of the coat colour types of farm animals is distinguishing between breeds and varieties based on this trait. Furthermore, for the sheep breeds which are kept for skins and wool, coat/skin colour is an important economic trait. Until now the study of coat colour inheritance in sheep proved the dominance of white colour over pigmented/black coat or skin and of black over brown.

This preliminary study aimed to differentiate domestic pigs from wild boars based on MC1R and NR6A1 polymorphisms and to identify admixture between these genomes. We studied samples obtained from wild boars from two regions of Poland and five pig breeds: Polish Landrace, Polish Large White, Złotnicka White, Pulawska and Duroc. Along the MC1R gene sequence, we identified four polymorphic loci comprising three codons. The “wild type” allele was primarily found in wild boar but also in the Duroc and Złotnicka White breeds. Non-wild type alleles were identified in the vast majority of domestic pig samples and in two wild boar samples. Based on MC1R profiles, we conducted a population study, and revealed admixture between both genomes using STRUCTURE and NETWORK Software. Interestingly, an allelic discrimination assay with NR6A1 g.748C > T TaqMan probes revealed a clear separation of samples into two groups: wild boar samples representing the C allele and domestic breeds representing the T allele. Based on the obtained results, we conclude that NR6A1 g.748C > T is an effective marker for differentiating between wild boars and domestic pigs, where this is supported by MC1R data, to identify admixed profiles. We recommend that a larger sample of genomes is studied to verify this method.

Simple Summary: Identification of mutations in the myostatin gene, affecting the occurrence of the double muscling phenotype in some breeds of beef cattle, was an impetus for further analysis and identification of mutations within this gene in other animal breeds, characterized by increased meat performance parameters. The number of geese in poultry livestock production in Poland is small. The native geese breeds can be successfully used to produce high-quality poultry meat and can be a very good source of goose meat production for regional and organic products. The aim of the study was to identify a mutation in the MSTN (Myostatin) gene and investigate whether this polymorphism can affect body weight in different periods of life in Landes and Kielecka breeds. Measurements of the examined trait were taken with time intervals to demonstrate the putative effect of the identified SNP (Single Nucleotide Polymorphism) on body weight over the course of bird growth. In conclusion, the identified c.1231C>T polymorphism suggests a possible link between the polymorphism and the BW (body weight) of Kielecka geese in the 12th week of life. The most significant factors affecting the BW values in geese are breed and sex.Abstract: Myostatin, also known as growth differentiation factor 8 (GDF8), belongs to the TGF-β superfamily of proteins. MSTN is a highly conserved protein that acts as a negative regulator of skeletal muscle growth. Loss of myostatin functionality causes the phenotype to appear in the form of 'double musculature', among others in cattle, sheep, and house mice. The presented results of the research were carried out on two geese breeds-Landes and Kielecka. The aim of the study was to identify mutations in the MSTN gene and study their impact on body weight in both geese breeds in different periods of life. Analysis of the obtained results showed the existence of polymorphism in exon 3 (c.1231C>T) and suggested a possible association (p < 0.05) between BW and genotype in 12 weeks of life in male Kielecka geese breed. The identified polymorphism may be one of the factors important for improving body weight in the studied Kielecka breed, therefore, it is necessary to conduct further research on a larger population of geese breeds in order to more accurately estimate the effect of the identified SNP c.1231C>T on BW in geese.

Animal fats are considered to be unhealthy, in contrast to vegetable fats, which are rich in unsaturated fatty acids. However, the use of some fats, such as coconut oil, is still controversial. In our experiment, we divided experimental animals (domestic pigs) into three groups differing only in the type of fat used in the diet: group R: rapeseed oil (n = 5); group B: beef tallow (n = 5); group C: coconut oil (n = 6). After transcriptomic analysis of liver samples, we identified 188, 93, and 53 DEGs (differentially expressed genes) in R vs. B, R vs. C, and B vs. C comparisons, respectively. Next, we performed a functional analysis of identified DEGs with String and IPA software. We observed the enrichment of genes engaged in the unfolded protein response (UPR) and the acute phase response among genes upregulated in B compared to R. In contrast, cholesterol biosynthesis and cholesterol efflux enrichments were observed among genes downregulated in B when compared to R. Moreover, activation of the UPR and inhibition of the sirtuin signaling pathway were noted in C when compared to R. The most striking difference in liver transcriptomic response between C and B was the activation of the acute phase response and inhibition of bile acid synthesis in the latest group. Our results suggest that excessive consumption of animal fats leads to the activation of a cascade of mutually propelling processes harmful to the liver: inflammation, UPR, and imbalances in the biosynthesis of cholesterol and bile acids via altered organelle membrane composition. Nevertheless, these studies should be extended with analysis at the level of proteins and their function.

the aim of the study was to analyse the association of ACACA and SCD1 polymorphism with milk composition, fatty acid profile in milk fat and milking performance of Polish Holstein-Friesian cows. The animals were divided according to criteria: lactation -1st, 2nd, 3rd, 4th; ACACA polymorphism -CC, CG, GG; SCD1 polymorphism -AA, VA, VV. The presence of A293V polymorphism of SCD1 gene in the population of Polish Holstein-Friesian cattle has been confirmed. In the analysed fragment of ACACA gene presence of a novel SNP has been revealed. The SNP AJ312201.1g.1488C>G consists of a substitution G>C in 1488 position. This ACACA polymorphism influenced C13:0, C14:1, C16:1 and CLA, while the analysed SCD1 polymorphism influenced C14:1. Interestingly, C16:0, C18:0 and C14:1 were influenced by fat content; while C16:1 was influenced by lactation stage; and CLA was influenced by both lactation stage and fat content. Although the novel SNP on ACACA gene and A293V on SCD1 showed only slight influence on fatty acid profile in this study, these genes are still potential candidate genes for fat content and composition in milk, but require further research.

Simple SummaryFreemartinism is the most common type of gender developmental disorder, resulting in infertility of heifers from multiple-sex twin pregnancies. The frequency of this syndrome is related to the frequency of multiple pregnancies, the number of which has significantly increased in dairy cattle populations (HF). Therefore, rapid diagnostics is necessary to enable early elimination of heifers with freemartinism from breeding. The aim of the study was to compare and identify the best method for early identification of freemartinism. The use of cytogenetic and molecular methods (PCR, short tandem repeats (STRs), real-time PCR) allowed us to conclude that molecular methods are more effective and guarantee fast and precise diagnosis. An additional advantage of molecular methods is the easy way to collect test material, which can be frozen, unlike blood samples for cytogenetic analysis, which must be fresh and delivered within 24 h to the laboratory, which generates further costs.AbstractFreemartinism in females born from heterosexual multiple pregnancies is characterized by the presence of XX/XY cell lines due to the formation of a shared blood system by anastomoses between fetal membranes of co–twins and leads to disturbed development of the reproductive system, including infertility. The aim of this study was to estimate the most precise and effective diagnostic method, especially useful for early identification of freemartinism in young female calves. The cytomolecular evaluation results of 24 Holstein-Friesian heifers from heterosexual twins was verified by molecular techniques: PCR, short tandem repeats (STRs), and relative quantitative PCR. The molecular analyses have been found to be a more efficient testing strategy, with a higher diagnostic success rate than karyotype evaluation. In 21 heifers, leucocyte chimerism determined by the 60, XX/60, XY karyotype was revealed—the proportion of the 60, XY male cell line in individual animals was in the range of 4–66%. In three cases, a normal karyotype 60, XX was identified, which indicates that anastomoses did not occur in 12.5% of studied twins and suggests that these potentially fertile heifers can be qualified for further breeding. The precise and early identification of freemartinism can be the basis for guidelines and selection recommendations concerning the reproductive performance of heifers born from heterosexual multiple pregnancies.

Scrapie, a fatal transmissible spongiform encephalopathy (TSE) occurs in two phenotypes: classical and atypical. Many authors point out that the polymorphism of three codons (136, 154, 171) of the PRNP (PrP gene) is associated with a sheep susceptibility to classical scrapie. Until now, only one PRNP gene variant coding phenylalanine at codon 141 has been found to be associated with atypical scrapie. Another recently identified and interesting candidate gene for scrapie susceptibility in sheep is an SPRN gene coding for Shadoo protein (Sho). Sho is a highly interspecies conserved protein and an insertion/deletion (indel) found in a sheep Sho gene was associated with classical scrapie occurrence. Here we determined the polymorphism of PRNP and SPRN genes in nine atypical scrapie cases (six in native born sheep and three in imported sheep) and compared these results with a control group of healthy animals comprising six corresponding Polish sheep breeds. In atypical scrapie cases five PRNP diplotypes were identified: A(136)R(154)Q(171)/ARQ, AHQ/ARQ, ARR/ARQ, ARR/AHQ and AHQ/AHQ. The ARR/AHQ diplotype was found only in imported sheep. A previously unobserved SNP in PRNP (E224K) was also found in both atypical scrapie and in a few control animals. In the ORF of the SPRN gene, six SNPs and one indel were identified. None of these variations was exclusive for scrapie animals and they were probably, naturally occurring polymorphisms. Special attention was given to the 6-bp indel SPRN polymorphism which was previously associated with classical scrapie occurrence.

Swine DNA profiling is of high importance for animal identification and parentage verification. The aim of this study was to test a set of 14 microsatellite (STR) markers recommended by ISAG for parentage verification in Polish Landrace (PL, n = 900), Polish Large White (PLW, n = 482), Pulawska (PUL, n = 127), and Duroc pigs (DU n = 108). The studied breeds showed a medium level of genetic differentiation. The average value of heterozygosity and degree of polymorphism (PIC) were above 0.5 for the studied breeds, except for the DU breed (PIC = 0.477). The population inbreeding coefficient indicates an absence of inbreeding in the studied breeds (an average value of FIS = 0.007). The cumulative power of discrimination for all breeds reached high values close to 1.0, while the probability of identity (PID) was low, with PID values ranging between 10−9 (for DU) and 10−12 (for PLW). The cumulative exclusion probability for PE1 and PE2 showed that the parentage can be confirmed with a probability of from 92.75% to 99.01% and from 99.49% to 99.97%, respectively.