M. Šprysl

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

BackgroundIndependent 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.MethodsSNP (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.ResultsLinkage 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.ConclusionsOur 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.

Effects of dietary linseed and corn supplement on the fatty acid content in the pork loin and backfat tissue

The influence of linseed and corn dietary supplements on the fatty acid (FA) composition of pork was evaluated. The effects of their appropriate use and dosage on pork meat and fat technological quality were also investigated. In total 72 pigs fed complete feed mixtures were divided into 4 groups: control (C), corn- (CD), linseed- (LD), and corn + linseed-supplemented (CLD). After slaughter the lean meat share, intramuscular fat content, meat and fat colour, shear force, drip loss, and malondialdehyde content were determined. Subsequently, the FA content and sum of saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) fatty acids, the n-6/n-3 fatty acid ratio, and atherogenic and thrombogenic indexes in the loin and backfat tissue were determined. Corn and lineseed supplementation increases the content of myristic, linoleic, α-linolenic, and eicosapentaenoic acids and reduces the amount of palmitic, palmitoleic, oleic, eicosenoic, and arachidonic acids. Therefore it reduces the PUFA/SFA ratio and improves atherogenic and thrombogenic indexes. No negative effects of linseed and corn supplementation on the technological characteristics of pork meat and backfat were registered. Due to the positive effects on indicators related to human health, linseed and maize supplementation can be recommended in pig diet.

Prediction of Pork Belly Composition Using the Computer Vision Method on Transverse Cross-Sections

Abstract The objective of this study was to identify the pig belly characteristics and to develop regression equations predicting its composition. Based on video image and chemical analysis of 216 bellies, the predictive variables were selected according to their relation to chemically determined belly lipid contents. To estimate the belly fat percentage (BF%), the two best equations constructed were: Equation 1: BF% = 49.960 - 0.7174 × SHME2 + 0.5047 × HE2A (R2 = 0.66, RMSE = 3.22); Equation 2: BF% = 43.888 - 0.6014 × SHME2 + 0.4769 × HE2A + 0.0014 × ARTO2 - 0.2697 × HE3A (R2 = 0.70, RMSE = 2.25), where: SHME2 = lean meat percentage area of the belly 2 from total cut area, HE2A = the Belly2 height at point 1, ARTO2 = the Belly2 total cut area, HE3A = the Belly3 height at point 1. Compared to lean meat, the percentage of belly fat (BF%) appears to be a more appropriate criterion for the objective evaluation of belly composition due to the simplicity and accuracy of the final regression equation (higher R2).

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.

The influence of controlled nutrition intensity on the muscle fiber characteristics in fattening pigs

The aim of this study was to evaluate the influence of controlled nutrition on the selected muscle fibres indicators and carcass value in pork. The test included 72 hybrid pigs of the D x (LWD x L) genotype of a balanced sex (barrows/gilts). Animals were divided into two groups; the 1st (control) group was fed ad libitum, while the nutrition of the 2nd (experimental) group was restricted upon reaching 80 kg of live weight. The nutritional restriction was achieved by feeding the animals with maximum dose of CFM up to 2.8 kg*day-1 (corresponding to 36.4 MJ ME*day-1, 46.76 g NS*day-1 and 23.52 g LYS*day-1). From the obtained results it is evident that the daily feed intake restriction corresponds with greater number of the MLLT muscle fibers as well as with a higher IIB type muscle fibers share, higher lean meat share and a higher shoulder proportion in the carcass.

Factors affecting the fatty acid composition and fat oxidative stability in pigs.

The aim of the study was to evaluate the effect of selected factors affecting fatty acids (FA) composition in pig fat. In the experiment, the influence of nutrition, gender,carcass weight, lean meat proportion (LMP) and intramuscular fat (IMF) were monitored. The effect of diet, specifically the influence of added linseed or corn on the fatty acids composition in the backfat was studied in pigs. From the perspective of the required increase of polyunsaturated fatty acids (PUFA) only the addition of the linseed proved to have a significant effect.Another evaluated aspect concerning the FA spectrum was the gender. While the backfat in barrows showed higher (P≤0.05) amount of monounsaturated fatty acids(MUFA), the backfat in gilts displayed a significantly higher proportion (P≤0.01) of the PUFA and total unsaturated fatty acids (UFA). A significant effect on the PUFA proportion has also been demonstrated for the lean meat proportion (LMP)parameter, which therefore represents not only a qualitative carcass meat parameter but also plays an important role in relation to the FA composition in the fat in pigs.In connection to the FA proportion changes the study also monitored the fat oxidative stability with the use of the TBARS method. Concerning the oxidative stability the effects of nutrition, FA groups, gender, carcass weight and LMP were studied. The relationship between the above mentioned factors and oxidative stability was found to be insignificant.

The repeatability effect to estimate the lean meat share in pigs

The aim of this work was to determine the accuracy of the lean meat share (LM) estimate with FOM instrumentation, in pigs. A total of 720 pigs were measured at slaughterhouses. The tests were carried out to determine the ability to measure the same value with repeated injections in the same point of the pig carcass, taking into account the operator, the equipment and the state. Based on the observed measurements it can be stated that the difference between measurements of the muscle and fat in the first and repeated injections is very low. The estimation in the CR, compared to the SR is, for both punctures, higher. As regards repeatability, it is obvious that the pig measuring in the SR is performed more carefully. Also, CR operators, compared to SR, exhibit, in the case of repeated punctures, a greater variability.

The analysis of the body composition changes during growth in pigs using the visual image analysis

The aim of the study was to estimate the live weight and lean meat percentage (LMP) using image analysis. The image analysis technique is based on finding certain anatomical proportions in pigs. The test was carried out with the use of 72 hybrids pigs. At the age of 120 and 170 days and at an ABW 64 and 110 kg, the animals were individually weighed and photographed. The total of 7 linear and 4 areal dimensions were measured on the live animals. Using correlation analysis, the relationship between average body weight (ABW), carcass quality and body measurements was determined. The study found higher positive correlation coefficients between the measured length dimensions and the weight of the main carcass parts. Video image analysis appears to be a suitable method for the body parts weight determination. However, the presumption of a reliable LMP estimation wasn’t confirmed in any of the measurements.