The g.4290 C>G Polymorphism in the FADS2 Gene Modifies the Fatty Acid Profile of the Pectoralis Superficialis Muscle of Ross 308 Broiler Chickens

The effect of the g.4290 C>G substitution in the FADS2 gene and g.285 C>T in the FABP4 gene on carcass quality, meat quality, and fatty acid profile of the pectoralis superficialis muscle of 238 male broiler chickens reared up to 45 days of age was analyzed. A significant influence of g.4290 C>G in the FADS2 gene on the pectoralis superficialis muscle fatty acid profile was demonstrated. Chickens with the GG genotype were characterized by the highest content of conjugated linoleic acid, amino acids, eicosapentaenoic acids, docosapentaenoic acid, docosahexaenoic acids. and the lowest value of the linoleic acid/alpha-linolenic acid ratio. The FABP4 polymorphism determined only the content of C18:1n-9, C18:2n-6 and docosahexaenoic acid. There was no effect of the studied genotypes on final body weight, carcass quality traits, or quality of broiler pectoral muscles.

Benzimidazole resistance in the ovine Haemonchus contortus from southern Poland - coproscopical and molecular findings.

UNLABELLED: Anthelmintic resistance within nematodes has become a very common issue, however, the data about its occurrence in the gastrointestinal nematodes of sheep in Poland are very limited. This study was carried out in order to evaluate the presence of benzimidazole resistance in highly pathogenic Haemonchus contortus by means of parasitological and molecular techniques. The research represents the first Polish attempt to confirm the presence of a mutation at codon 200 of the ß-tubulin isotype 1 gene in H. contortus by PCR-RFLP. The occurrence of this mutation indicates the risk of ineffective benzimidazole treatment, nowadays commonly used for parasite control in Poland. The resistant parasites were detected by means of FECRT in a sheep flock (30 individuals) from southern Poland. To confirm the resistance on the molecular level, primers designed according to the sequences available in Genebank were used to detect the mutation. Unfortunately, as the PCR product was shorter than required (403 bp), further analyses are needed. The obtained results may indicate the high variability within the parasite population. Hence, it is essential to adapt the reaction conditions to our geographic strain of the nematode - and further analyses are required. KEY WORDS: Haemonchus contortus, benzimidazole resistance, PCR, Poland.

Identification of a new haplotype within the promoter region of the MSTN gene in horses from five of the most common breeds in Poland.

Myostatin (GDF-8) encoded by the MSTN gene is a negative regulator of muscle growth and development and belongs to the TGF-ß superfamily of secreted growth and differentiation factors. In Thoroughbred horses, an MSTN sequence polymorphism (g.66493737C>T) is associated with optimum race distance. In the present study, a genetic polymorphism of a predicted promoter of the MSTN gene was investigated in 451 horses belonging to five different breeds: Arabian, Thoroughbred, Polish Konik, Hucul and Polish Heavy Draft. Two SNPs located at g.66495826T>C and g.66495696T>C (chr;18 EquCab 2.0) showed three haplotypes previously described: [g.66495826:T, g.66495696:T], [g.66495826:T, g.66495696:C], [g.66495826:C, g.66495696:T] with frequencies 0.877; 0.101; 0.005; respectively. Analysis performed on Polish Heavy Draft indicated the occurrence of a new haplotype [g.6649582626:C, g.66495696:C] with frequency 0.016.

[Stearoyl-CoA desaturase--the lipid metabolism regulator]. / Desaturaza stearylo-CoA--regulator metabolizmu lipidów.

Stearoyl-CoA desaturase is an enzyme from the class of oxidoreductase, which catalyzes the formation of a fatty acid double bond between C9 and C10. It plays a key role in composition of the fatty acid profile in adipose tissue and animal products such as meat and milk. Additionally, it is an important regulator of metabolic processes in the body, and it determines the maintenance of energy homeostasis. This enzyme is encoded by an SCD gene, which, depending on the species, may exist as different isoforms. mRNA expression of stearoyl-CoA desaturase is dependent on many factors, including diet, hormones, and the activity of other genes. In previous studies, several mutations were characterized within the sequence of Δ9-desaturase, which may affect the activity of the protein in the tissues, as well as the value of breeding animals. Effects of particular mutations of the gene encoding the enzyme appears to be particularly important for diseases associated with obesity, diabetes, hypertension, heart diseases or cancer in humans. Also, it seems that using sheep as a potential animal model could be helpful in uncovering and understanding the mechanisms regulated by stearoyl-CoA desaturase.

[MSTN gene polymorphism in livestock animals]. / Polimorfizm genu miostatyny (MSTN) u zwierzat domowych.

Myostatin, also known as GDF8 (growth differentiation factor 8), belongs to one of the biggest groups of proteins, called transforming growth factors (TGF-ß). The protein regulates embryonic development and maintains homeostasis of full-grown individuals. When the process of maturation is over, GDF8 becomes a negative regulator of skeletal muscle growth. The physiological role of myostatin is to prevent overgrowth of muscle tissue in various stages of organism development. It also inhibits the regeneration of skeletal muscles by weakening activation and proliferation of satellite cells and the migration of macrophages and myoblasts to the site of injury. Several mutations within the sequence of MSTN have been described; they may affect the activity of the protein in the tissues, and hence the level of the functional characteristics of the animals, which determine the value of breeding animals. Understanding the impact of individual mutations in the gene encoding the protein is particularly important in relation to production traits of livestock.

Effect of polymorphisms at the ghrelin gene locus on carcass, microstructure and physicochemical properties of longissimus lumborum muscle of Polish Landrace pigs.

The influence of RFLP-BsrI polymorphisms at the ghrelin gene locus on carcass, meat quality parameters and muscle fiber characteristics of longissimus lumborum was studied in 168 barrows of the Polish Landrace breed. Analysis revealed a high frequency of the 1 allele (0.60) with the frequencies of the 11, 12 and 22 genotypes being 0.45, 0.30 and 0.25, respectively. The most favorable parameters of meat traits were characteristic of pigs with the 22 genotype, together with a higher carcass and loin weight and lower thermal loss compared to 12 heterozygotes. The highest fat content was found in pigs with the 11 genotype, which had the highest abdominal fat weight and mean backfat thickness. Meanwhile, the 12 heterozygotes were characterized by the largest loin eye areas, highest lightness (L*) and yellowness (b*) values, and lowest redness (a*) values, as well as the greatest hardness and chewiness and largest diameter of type IIB muscle fibers compared to the other genotypes.

Effect of g.2728g > A and g.3996t > C polymorphisms at the leptin gene locus on microstructure and physicochemical properties of longissimus lumborum muscle of Polish Landrace pigs.

The influence ofHindIII (g.2728G > A) and Bg/II (g.3996 T > C) polymorphisms at the leptin gene locus on muscle fibre characteristics and meat quality of longissimus lumborum muscle was studied in 146 barrows of the Polish Landrace breed. Leptin gene polymorphism was identified by PCR-RFLP. Fibre type percentage, fibre diameter and the following technological parameters ofmeat were also determined: pH45, pH24, L*a*b* colour, drip loss, water holding capacity, shear force and intramuscular fat content. Polymorphism was not detected in the locus studied in the Landrace pig herd analysed with the Bg/II restriction enzyme (g.3996 T > C). For the HindIII enzyme (g.2728G > A), there was a high frequency of GG homozygotes (0.78) and G allele (0.89), but the AA genotype was not present. Moreover, the genotypes ofleptin gene RFLP-HindIII polymorphism had no effect on intramuscular fat content and muscle fibre type percentage, but had a significant effect on muscle fibre size. Heterozygous GA fatteners had a significantly larger (P < 0.05) diameter of type IIB and type I fibres compared to homozygous GG fatteners. Generally, meat quality parameters were comparable among the examined genotypes except for water holding capacity (which was the lowest for the GG genotype) and colour lightness (L*) (which was the lightest for GA genotype). Moreover, regardless of genotype, large differences were observed between each animal in the distribution of intramuscular fat.