The Effect of the Boar Taint Masking Strategy (Adding Dried Origanum vulgare or Allium sativum) on Sensory Characteristics.

With increasing efforts to ban surgical castration, it is important to find ways to mask the level of boar taint in meat. The aim of this study was to test the possibility of masking boar taint or skatole levels by adding dried Origanum vulgare or Allium sativum and to evaluate consumer sensory preferences towards the skatole concentration in different carcass parts (longissimus lumborum; semimembranosus; neck chop and subcutaneous fat) and the masking strategy (addition of Allium sativum or Origanum vulgare). In the first experiment, the effect of the masking strategy was evaluated at three different skatole concentrations (0.069, 0.269 and 0.463 µg/g). The results showed that the samples with low and medium skatole levels were significantly different between the control group and the groups treated with Origanum vulgare or Allium sativum. In both cases, the addition of Allium sativum and Origanum vulgare had a positive effect on the parameters of abnormal odour and pleasantness of odour (p < 0.05). According to the results of the second experiment, meat samples from leaner parts, such as the neck chop semimembranosus and longissimus lumborum, not treated with Allium sativum and Origanum vulgare for masking, were significantly (p < 0.05) worse in terms of the occurrence of boar taint or abnormal odour than the masked samples. No significant differences were found between the two masking methods.

Eating Quality of Pork from Entire Male Pigs after Dietary Supplementation with Hydrolysable Tannins.

Boar taint is an unpleasant odour and flavour released during heat treatment of pork from uncastrated male pigs. The two main compounds responsible for boar taint are androstenone and skatole. Androstenone is a steroid hormone formed in the testis during sexual maturity. Skatole is a product of microbial degradation of the amino acid tryptophan in the hindgut of pigs. Both of these compounds are lipophilic, which means that they can be deposited in adipose tissue. Several studies have reported heritability estimates for their deposition from medium (skatole) to high magnitudes (androstenone). In addition to efforts to influence boar taint through genetic selection, much attention has also been paid to reducing its incidence using various feeding strategies. From this point of view, research has focused especially on the reduction in skatole content by supplementation of feed additives into the nutrition of entire male pigs. Promising results have been achieved using hydrolysable tannins in the diet. To date, most studies have investigated the effects of tannins on the production and accumulation of skatole in adipose tissue, intestinal microbiota, growth rate, carcasses and pork quality. Thus, the objective of this study was, in addition to determining the effects of tannins on androstenone and skatole accumulation, to assess the effects of tannins on the sensory traits of meat from entire males. The experiment was performed on 80 young boars-progeny of several hybrid sire lines. Animals were randomly assigned to one control and four experimental groups (each numbering 16). The control group (T0) received a standard diet without any tannin supplementation. Experimental groups were supplemented with 1% (T1), 2% (T2), 3% (T3) or 4% (T4) SCWE (sweet chestnut wood extract) rich in hydrolysable tannins (Farmatan). Pigs received this supplement for 40 days prior to slaughter. Subsequently, the pigs were slaughtered, and sensory analysis was applied to evaluate the odour, flavour, tenderness and juiciness of the pork. The results showed a significant effect of tannins on skatole accumulation in adipose tissue (p = 0.052-0.055). The odour and flavour of the pork were not affected by tannins. However, juiciness and tenderness were reduced by higher tannin supplementation (T3-T4) compared to the controls (p < 0.05), but these results were sex-dependent (in favour of men compared to women). Generally, women rated tenderness and juiciness worse than men regardless of the type of diet.

Changes of Androstenone Concentrations in Saliva of Boars with Age.

With the increasing age of boars, the possibility of androstenone (5α-androst-16-en-3-one (AND), 5α-androst-16-en-3α-ol (α-AND), and 5α-androst-16-en-3ß-ol (ß-AND)) occurrence increases as well. The aim of this study was to evaluate concentrations of androstenone compounds in the saliva of boars concerning the age of animals. In total, 72 boars were evaluated (24 boars per replication). The effect of age (three different ages-152, 163, and 172 days) was observed, and (Landrace × Large White) × Pietrain genotypes were used. Chemical analysis of saliva samples was conducted by multidimensional gas chromatography/mass spectrometry (MDGC/MS). Salivary α-AND increased with age (p < 0.05), and positive correlations were found between age and submaxillary salivary gland weight (p < 0.05), age, and salivary AND concentration (p < 0.05), body weight and submaxillary salivary gland weight (p < 0.05), submaxillary salivary gland weight and salivary ß-AND concentration (p < 0.05), as well as submaxillary salivary gland weight and total salivary 5α-androstenone (AND total) concentration (p < 0.001). Nowadays, animal welfare is becoming a more and more discussed topic, and pig breeding is not an exception. Specifically, the castration ban is a current issue, so it is very important to know as much as possible about compounds responsible for boar taint. Androstenone's appearance in boars' saliva could be one of the most important precursors for future early detection of boar taint.

The impact of bisphenols on reproductive system and on offspring in pigs - A review 2011-2020.

This study summarizes the knowledge about effects of bisphenol A (BPA) and its analogues on reproduction of pigs and some parameters of their offspring during period 2011-2020. Bisphenols are known as one of the most harmful environmental toxicants with endocrine-disrupting properties. One study in the reference period related to male reproductive system. Treatment with an antagonist of G-protein coupled estrogen receptor (GPER) - G15, and bisphenol A and its analogues, tetrabromobisphenol A (TBBPA) and tetrachromobisphenol A (TCBPA) diversely disrupted protein molecules controlling the biogenesis and function of microRNA in Leydig cells. Nine studies examined the effect of BPA, bisphenol S (BPS) or fluorene-9-bisphenol (BHPF) on female reproductive system. From the possible protective effect's point of view seems to be perspective the administration of melatonin in BPA-exposed oocytes. Finally, two studies were found to evaluate the maternal exposure to BPA on offspring's meat quality, muscle metabolism and oxidative stress. Administration of methyl donor improved antioxidant enzymes activity and reduced oxidative stress in piglets.

Association analysis of SNPs in the porcine CYP2E1 gene with skatole, indole, and androstenone levels in backfat of a crossbred pig population.

The occurrence of boar taint in meat from uncastrated males may significantly affect the economics of pork production. The aim of this study was to analyse associations of four single nucleotide polymorphisms (SNPs) in the porcine CYP2E1 gene with skatole, indole, and androstenone levels in the Czech Large White-Czech Landrace commercial crossbreds. The SNPs were: g.2412C>T, c.1422C>T, c.1423G>A and c.*14G>T. Skatole, indole and androstenone levels were estimated by HPLC, and genotypes at the SNPs were determined by PCR-RFLP. SNPs c.1423G>A and c.*14G>T were in complete linkage disequilibrium. In boars, all SNPs were associated with the indole levels (P<0.05; P<0.01). There also were differences in the skatole levels in different genotypes, but these were not significant. No associations with androstenone levels were found. The associations of the SNPs with indole compounds should be studied in other commercial populations of boars to verify the favourable alleles and genotypes, with the prospect for their application in marker-assisted selection.

Porcine EEF1A1 and EEF1A2 genes: genomic structure, polymorphism, mapping and expression.

Eukaryotic translation elongation factor 1 alpha (EEF1A) plays a key role in protein synthesis. In higher vertebrates EEF1A occurs in two isoforms, EEF1A1 and EEF1A2, encoded by distinct genes. The purpose of this study was to compare the two porcine genes as for the genomic sequence, gene organization and mRNA expression in different tissues, as well as to search for polymorphism and chromosomal assignment. Standard methods of DNA and mRNA analysis were used. We determined the complete genomic sequence of the porcine EEF1A1 and EEF1A2 genes. The two genes differ in the lengths of transcription units (3102 and 8588 bp, respectively), but have similar genomic organization and their coding sequences are highly similar (78% identity of coding sequences and 92.4% identity of amino acid sequences). Several polymorphisms in the two genes were detected. EEF1A1 and EEF1A2 were mapped to SSC1p11.1 and SSC17q23.3, respectively. mRNA of EEF1A1 was expressed in all studied tissues (the highest expression was in 44-day fetal muscle and low expression in adult liver and brain), while EEF1A2 was expressed only in skeletal-muscle, tongue, heart, diaphragm and brain tissues. EEF1A2 was not expressed in fetal muscle tissue (44 days). In this paper results are provided on genomic sequences, genomic organization, polymorphism, chromosomal assignment and spatial and temporal expressions of the porcine EEF1A1 and EEF1A2 genes. Novel polymorphisms were described in both genes. Porcine EEF1A2 was studied for the first time.

Association between polymorphism in the FTO gene and growth and carcass traits in pig crosses.

BACKGROUND: Independent studies have shown that several single nucleotide polymorphisms (SNP) in the human FTO (fat mass and obesity associated) gene are associated with obesity. SNP have also been identified in the pig FTO gene, among which some are associated with selected fat-deposition traits in F2 crosses and commercial populations. In this study, using both commercial pig populations and an experimental Meishan × Pietrain F2 population, we have investigated the association between one FTO SNP and several growth and carcass traits. Association analyses were performed with the FTO polymorphism either alone or in combination with polymorphisms in flanking loci. METHODS: SNP (FM244720:g.400C>G) in exon 3 of porcine FTO was genotyped by PCR-RFLP and tested for associations with some growth, carcass and fat-related traits. Proportions of genetic variance of four pig chromosome 6 genes (FTO, RYR1, LIPE and TGFB1) on selected traits were evaluated using single- and multi-locus models. RESULTS: Linkage analysis placed FTO on the p arm of pig chromosome 6, approximately 22 cM from RYR1. In the commercial populations, allele C of the FTO SNP was significantly associated with back fat depth and allele G with muscling traits. In the Meishan × Pietrain F2 pigs, heterozygotes with allele C from the Pietrain sows and allele G from the Meishan boar were more significantly associated with fat-related traits compared to homozygotes with allele G from the Pietrain and allele G from the Meishan breed. In single- and multi-locus models, genes RYR1, TGFB1 and FTO showed high associations. The contribution in genetic variance from the polymorphism in the FTO gene was highest for back fat depth, meat area on the musculus longissimus lumborum et thoracis tissues and metabolite glucose-6-phosphate dehydrogenase. CONCLUSIONS: Our results show that in pig, FTO influences back fat depth in the commercial populations, while in the Meishan × Pietrain F2 pigs with a CG genotype, heterosis occurs for several fat-related traits.