Monika Okrouhlá

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.

COMPARISON OF DIFFERENT SORTING OF FATTY ACID IN BOVINE MILK IN RELATION TO BODY CONDITION OF CZECH FLECKVIEH DAIRY COWS

Fatty acids in milk are one of the most important components of milk. The aim of this study was to determinate relationships between groups of fatty acids and body condition score change in Czech Fleckvieh cows. Fatty acids were classification along its length of chain and its source of creation. To analysis was included total of 50 Czech Fleckvieh cows with different order of lactation. During the first 4 weeks of lactation, milk samples were collected at a weekly interval and body condition score was assessed. Statistical analyses were performed using Microsoft Office Excel and the procedures MEANS and GLM of SAS 9.1. During the first four week of lactation, the proportions of short- and medium-chain fatty acids as well as de novo synthesised fatty acids increased. Moreover the cows with a greater body condition score change mobilized storage depot fat more intensively, which resulted in higher proportions of dietary and depot fatty acids since week 1 of lactation, and long-chain fatty acids since week 2 of lactation. On the contrary, the animals with only a small body condition score change exhibited high proportions of short- and medium-fatty acids as well as de novo synthesised fatty acids in the most part of the period analysed. This indicates abut negative energy balance in early part of lactation and its compensation. The results also confirm the relationships between different groups of fatty acids, body condition score and negative energy balance. As more accurate for evaluation of intensity of negative energy balance was confirmed rather classification along source of creation. These results further emphasize importance the monitoring of body condition, milk composition and good herd management in first part of lactation.

The relationship between fatty acid and citric acid concentrations in milk from Holstein cows uring the period of negative energy balance

The objective of this study was to determine the relationship between body condition score changes and the dynamics of energy balance indicators - fatty acid and citric acid contents - in milk during a early part of lactation. In addition, the relationship between these two indicators was also evaluated. A total of 27 Holstein cows that calved within three consecutive weeks were included in the analysis. During the first 17 weeks of lactation, milk samples were collected at a weekly interval and body condition score was assessed once a month. Statistical analyses were performed using Microsoft Office Excel and the procedures MEANS and CORR of SAS 9.1. Trend functions describing the development of fatty acid and citric acid contents explained 67.67 to 92.19 % of their variability. Similar relationships between fatty acid and citric acid contents and the changes in body condition score during the first three months of lactation were observed. In addition, a similar decreasing tendency was also determined for the contents of both the dependent variables in this period. Significant correlations (P0.01 – 0.001) were calculated (r = 0.51 – 0.74) for lactation weeks 6 and 7, thus before the subsequent decrease of body condition score by 0.2 points between weeks 8 and 12 after parturition. The results indicate the possibility of using the contents of fatty acids and citric acid as indicators of energy balance in dairy cows. The results also confirm the relationships between these indicators and emphasise the importance of proper herd management with respect to body condition score changes and the contents of fatty acids and citric acid in milk.

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.

Nutritional Effects on Boar Taint in Entire Male Pigs: A Review

Abstract Boar taint is one of topical problems in fattening pigs. It is caused by two main compounds — androstenone and skatole. Androstenone is a steroid feromone, which is synthesized and metabolized in liver and testes. Skatole is produced by intestinal bacteria by metabolization of trypthophan. Both these substances are metabolized by cytochrome P450 and the unmetabolized residues accumulate in adipose tissue. This review describes the possible nutritional effects on boar taint reduction. Skatole is the main component, which could be reduced by nutrition in entire male pigs. The presence in adipose tissue can be reduced by apoptosis of intestinal cells by raw potato starch. Another method is to influence the microbial population in the gastrointestinal tract by organic acids or fructooligosaccharides. Recently, attention has been directed towards the enzymatic system in the liver. There are a few possibilities of reducing skatole as well as androstenone by influencing the liver enzymatic system. They may be particularly affected by secondary plant metabolites and flavonoids. However, more research is required in this area to clarify physiological regularities and all the relationships in the metabolism detoxification from xenobiotic substances.

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 effect of gender on the characteristics of muscle fibers in pork.

The aim of this study was to evaluate the influence of gender on the proportional representation of different types of muscle fibres and their selected characteristics. The experiment was carried out with the use of 72 crossbred pigs of final TOPIGS hybrid combination with balanced gender ratio (24 boars/24 gilts/24 barrows) at an average live weight of 22.5 kg. The average slaughter weight of the animals was 108.7 kg. In order to determine the quantitative (number) and qualitative (area, diameter, length) characteristics of the muscle fibre, samples were obtained from the loin carcass part, specifically the muscle musculus longissimus lumborum et thoracis (MLLT). These samples were used for the manufacture and evaluation of permanent histological slides. There were negative correlations found between the number of muscle fibres and their size. Gilts had the highest number of muscle fibres (208.55) per measured surface (1 mm2) and simultaneously the smallest diameter (66.31 μm) of muscle fibres in comparison with boars and barrows. Statistically significant (P<0.05) differences in the area and diameter of muscle fibres type IIA were detected between gilts and barrows.