Lean Meat Content Research Articles

Effect of the Ser638Arg variation in the cast gene and causal SNP g.1843C>T in the RYR1 gene on carcass traits in crosbreed pigs

The objectives of this investigation was to demonstrate that genotypes of calpastatin (CAST) Ser368Arg and ryadonide receptor 1 (RYR1) g.1843C>T may affect the carcass traits of pigs. Association analysis of the aforementioned SNPs was performed on 518 pigs included eight commercial crossbreeds and one pure pig breed. All pigs were slaughtered at average body weight of 113kg. Genotypes at the SNPs were determined by PCR-RFLP. There were found only two genotypes of RYR1 gene: CC (428 pigs) and CT (90 pigs) in this study. The effect of allele C compared to allele T on the higher fat content of pig carcass was confirmed. The allelic frequencies of allele 638Ser (C) and allele 638Arg (A) were 0.26 and 0.74, respectively. The significant association (P<0.05) was occurred between allele A and higher fat content, and between C allele and higher lean meat content. Our results showed no significant effect of the observed polymorphismSer638Arg on the intramuscular fat content or other indicators of carcass value.

Prediction of primal cuts by using an automatic ultrasonic device as a new method for estimating a pig-carcass slaughter and commercial value

The objective of the present work was to develop regression equations to estimate the percentage, weight (in g) and lean meat content (in %) of the primal cuts of a pig carcass by using Auto-Fom and to estimate the commercial value of the carcass on the slaughter line in a meat-processing plant. The research was conducted on 168 pig carcasses. From the whole pork carcass, only the most valuable cuts (i.e. belly, ham, loin, neck and shoulder) and also meat content in ham and shoulder were weighed at a 100 g accuracy and the percentage of each cut in carcass was calculated. Loin ‘eye’ height and belly-muscle thickness were also measured. The regression equations for the prediction of the primal-cut weights and their percentages in the pig carcasses were derived using the partial least-square procedure. The developed equations include 70 variables that are standard measurements taken with an Auto-Fom device. These equations have a satisfactory accuracy rate and are useful in estimating the yield of the elements, especially for loin, ham and belly content. Belly-muscle thickness (R2 = 0.98) and the percentage of meat in the ham (R2 = 0.93) can be estimated with a high precision. It was confirmed that the developed equations may be used in the current Auto-Fom software.

Muscle fibre composition and meat quality in pigs with different nutrition level

A total of 60 crossbred pigs were divided to 3 feeding groups - ad libitum (AL), restriction (R1) and strong restriction (R2) and the effect of feed restriction on muscle fibre characteristics of musculus longissimus lumborum (MLL) and meat quality traits were evaluated. Muscle fibres were stained and classified as fibre types I, IIA and IIB. For each muscle fibre type, the fibre density, fibre cross-section area (CSA) and fibre proportion were determined. Fibres IIB were divided to small-, medium- and large-sized fibres. From qualitative meat parameters, meat colour, tenderness, water-holding capacity, pH, and electrical conductivity were measured. AL group had significantly lower area percentage of IIB fibres and lower CSA of IIB fibres than restricted groups. R2 group had significantly higher content of large-sized IIB fibres and lower content of medium-sized IIB fibres than AL group. Ad libitum fed group had the highest back fat thickness and the lowest lean meat content and tended to have better meat quality traits compared to other groups. The results of this study showed that strong feed restriction had a negative effect on muscle fibre composition, especially amount of large-sized fibres IIB, which are associated with poor meat quality.

Effects of a Novel p.A41P Mutation in the Swine Myogenic factor 5(MYF5) Gene on Protein Stabilizing, Muscle Fiber Characteristics and Meat Quality.

Myogenic factor 5 (MYF5) plays an important role in regulating skeletal muscle fiber characteristics, consequently affecting meat production and quality. We identified a novel p.A41P mutation in exon1 of the porcine MYF5 gene by direct sequencing. The mutation was predicted to be destabilizing in protein structure based on the resultant amino acid substitution. We estimated the significant substitution effect of p.A41P on the energy stabilization of Myf5 protein structure. Then, we demonstrated that the mutation in Yorkshire population significantly affected muscle fiber type I composition (p<0.05), loin-eye area of lean meat content (p<0.05) and filter-fluid uptake of meat quality (p<0.01). Furthermore, dominant effects significantly influenced total muscle fiber number (p<0.05). This study suggests that the novel p.A41P mutation in porcine MYF5 may be a valuable genetic marker to affect the muscle fiber characteristics and consequently improve meat production quality and quantity.

Effect of ractopamine on digestible-lysine requirement for finishing barrows under thermoneutral conditions

The purpose of the present study was to determine the digestible-lysine (Lys) requirement in diets supplemented or not with ractopamine (RAC), so as to maximise performance and carcass characteristics for finishing barrows reared at thermoneutral conditions. In total, 128 high-lean commercial hybrid barrows with an initial bodyweight of 78.2 ± 4.3 kg were distributed in a completely randomised block design, in a 4 × 2 factorial arrangement (four Lys concentrations: 0.730%, 0.830%, 0.930% and 1.030% and two RAC inclusions: 0 and 10 mg/kg), with two animals per pen and eight pens per treatment. Lys concentrations tested significantly (P &amp;lt; 0.05) affected digestible-lysine intake, and the absolute (g) and relative (%) lean meat content, regardless of RAC inclusion. When diets were RAC-supplemented, feed conversion rate of animals was improved and, in addition, final bodyweight, daily bodyweight gain, loin eye area, loin eye depth, and absolute (g) and relative (%) carcass lean meat content increased (P &amp;lt; 0.05). RAC inclusion also decreased (P &amp;lt; 0.05) backfat thickness and the colour values a* and b* of finishing pigs. Therefore, on the basis of our results, it can be inferred that the best performance and carcass characteristics for finishing barrows reared at thermoneutral conditions were obtained at 1.030% and 0.730% Lys respectively, corresponding to an estimated daily Lys intake of 34.3 g and 24.2 g, independently of the diet RAC concentration.

Effects of using locally produced protein feed ingredients in low protein diets to single-phase-fed growing-finishing pigs

ABSTRACTIn two trials, 358 female and entire male pigs vaccinated against boar taint (YxH) were single-phase-fed with diets that were planned to contain 0.78 g standardized ileal digestible (SID) lysine/MJ net energy and 14.5 g SID CP/g SID lysine. A reference diet with soya bean meal (SBM) as the protein feed ingredient, was replaced with either cereal by-products (CBP), rapeseed meal (RSM), faba beans (FB) or mixtures of 50% CBP and 50% RSM (CBP + RSM) or 50% FB and 50% RSM (FB + RSM) in the experimental diets. Treatments had no effect (P > 0.05) on daily weight gain, feed efficiency, carcass weight, lean meat content or dressing percentage and carcass value. Single-phase-fed pigs on diets with local protein ingredients can perform as well as single-phase-fed pigs on diets with soya bean meal, and CBP, RSM, FB have the potential to replace soya bean meal in nutritionally well-balanced diets to growing-finishing pigs.

Growth and Meat Quality of Prestice Black-Pied and (Landrace × Large White) × Duroc Pigs

The objective of the performed experiment was to evaluate growth performance and selected carcass traits and meat quality parameters in pigs of a native Czech breed Prestice Black-Pied pig (PB) and a commercial hybrid (H) used for meat production. The observation included 40 pigs, 20 pigs of the native breed PB and 20 pigs of the hybrid combination. The PB piglets showed higher (P ≤ 0.05) birth weight than the H piglets. The lifetime weight gain was higher (P ≤ 0.01) in the H pigs than in the PB pigs. The results also showed higher (P ≤ 0.01) backfat thickness in the PB breed than in the H pigs. Lean meat content was higher (P ≤ 0.01) in the hybrid pigs than in the PB breed. Higher (P ≤ 0.01) values of intramuscular fat content were found in the PB pigs than in the H pigs. Drip loss value was higher (P ≤ 0.01) in the H pigs by 1.3 % than in the PB pigs. The PB pigs showed more favourable (P ≤ 0.05) values of pH45,24 in comparison with the hybrid pigs.

Carcass characteristics of grass-fed crossbred bulls and steers slaughtered at two different ages

The aim of this study was to evaluate beef production potential and meat quality in young crossbred bulls and steers raised indoors and fed grass-based diets. One half of 96 bull calves were castrated at 2–3 wk of age. The calves were fed standard diets, and starting at 7 mo of age, they received grass silage supplemented with concentrates. At the end of the fattening period (18 and 21 mo of age), the animals were slaughtered, carcass quality was evaluated, and samples of musculus longissimus thoracis were collected to determine the proximate composition and meat quality. The semi-intensive feeding system contributed to higher daily gains (0.835 kg) in Holstein-Friesian (HF) × Hereford (HH) crosses. In comparison with steers, bulls were characterized by a higher dressing percentage (+1.33%), higher weight of five most valuable primal cuts (+6.7 kg), and higher lean meat content of three-rib cuts (+7.54%). Meat from steer carcasses, which had higher fat content was more tender and had desirable aroma, juiciness, and flavor. In semi-intensive production systems, steers performed better than bulls, and HF × HH crosses were more suitable than HF × Limousin (LM) and HF × Charolais (CH) crosses. Dairy-beef crosses should be slaughtered at 21 mo of age to improve carcass quality.

Changes in the content of edible and non-edible components and distribution of tissue components in cockerels and capons

The aim of this study was to determine the effects of castration and age on the content of edible and non-edible components, and the distribution of tissue components in the carcasses of cockerels and capons. The study was conducted on 200 birds (Green-legged Partridge), divided into two sex categories (with 5 replications per group and 20 birds per replication), raised to 28 wk of age. At 8 wk of age, 100 birds were surgically castrated and afterwards at 12 wk of age and at four-wk intervals, 10 intact cockerels and 10 capons were selected randomly and slaughtered. Cockerels, compared with capons, were characterized by a higher proportion of edible components at 24 and 28 wk of age, and a more desirable carcass tissue composition due to a higher content of lean meat in total body weight (BW). Capons had higher abdominal fat content than cockerels, which resulted in a higher percentage of non-edible components in their BW at 24 and 28 wk of age. Differences in the distribution of lean meat in the carcass were noted from 20 wk of age in both castrated and intact birds. The content of breast muscles increased in capons, and the content of leg muscles (thigh and drumstick) increased in cockerels. The results of this study indicate that in view of the optimal lean meat content of the carcass and the optimal distribution of major tissue components, Green-legged Partridge capons should be fattened for a maximum period of 24 wk.

Examining the Genetic Background of Porcine Muscle Growth and Development Based on Transcriptome and miRNAome Data.

Recently, selection in pigs has been focused on improving the lean meat content in carcasses; this focus has been most evident in breeds constituting a paternal component in breeding. Such sire-breeds are used to improve the meat quantity of cross-breed pig lines. However, even in one breed, a significant variation in the meatiness level can be observed. In the present study, the comprehensive analysis of genes and microRNA expression profiles in porcine muscle tissue was applied to identify the genetic background of meat content. The comparison was performed between whole gene expression and miRNA profiles of muscle tissue collected from two sire-line pig breeds (Pietrain, Hampshire). The RNA-seq approach allowed the identification of 627 and 416 differentially expressed genes (DEGs) between pig groups differing in terms of loin weight between Pietrain and Hampshire breeds, respectively. The comparison of miRNA profiles showed differential expression of 57 microRNAs for Hampshire and 34 miRNAs for Pietrain pigs. Next, 43 genes and 18 miRNAs were selected as differentially expressed in both breeds and potentially related to muscle development. According to Gene Ontology analysis, identified DEGs and microRNAs were involved in the regulation of the cell cycle, fatty acid biosynthesis and regulation of the actin cytoskeleton. The most deregulated pathways dependent on muscle mass were the Hippo signalling pathway connected with the TGF-β signalling pathway and controlling organ size via the regulation of ubiquitin-mediated proteolysis, cell proliferation and apoptosis. The identified target genes were also involved in pathways such as the FoxO signalling pathway, signalling pathways regulating pluripotency of stem cells and the PI3K-Akt signalling pathway. The obtained results indicate molecular mechanisms controlling porcine muscle growth and development. Identified genes (SOX2, SIRT1, KLF4, PAX6 and genes belonging to the transforming growth factor beta superfamily) could be considered candidate genes for determining muscle mass in pigs.

Dietary supplementation of finishing pigs with the docosahexaenoic acid-rich microalgae, Aurantiochytrium limacinum: effects on performance, carcass characteristics and tissue fatty acid profile.

ObjectiveThe aim of this experiment was to evaluate the effect of dietary supplementation with the docosahexaenoic acid (DHA)-rich microalgae, Aurantiochytrium limacinum (AURA) on pig performance, carcass traits, and the fatty acid composition of pork Longissimus lumborum (LL) and backfat.MethodsA total of 144 Pig Improvement Company (PIC)×Goland finishing pigs (72 females and 72 castrated males) of mean weight 117.1 (±13.1) kg were blocked by sex and body weight and provided with 0% or 1% AURA in isonutritive and isocaloric diets. A total of 24 pens provided 12 replicates per treatment. Animals were weighed on day 0 and 28 with feed and water intake recorded per pen. After 31 days supplementation (28 days of study and 3 days until the slaughtering date) three animals per pen (n = 72) were slaughtered and the LL and backfat thickness, lean meat content and dressing percentage were recorded for the carcasses. The fatty acid (FA) profile of the LL and backfat was established by direct FA methyl ester synthesis.ResultsNo differences were observed for any performance parameters or carcass traits. Supplementation with AURA resulted in significant changes to the FA profiles of both the LL and backfat with male and female pigs responding differently to supplementation in terms of particular FAs. Overall, pork LL samples had significantly higher eicosapentaenoic acid (p<0.001) and DHA concentrations (p<0.001), and higher omega-3 (n-3) FAs (p<0.001), as well as an increased omega3:omega6 (n-3:n-6) ratio (p = 0.001). For backfat, supplementation resulted in significantly higher amounts of DHA (p<0.001) and n-3 FAs (p<0.001).ConclusionThese results indicate that dietary supplementation with 1% AURA over a 31 day period can increase the FA composition of pork LL and backfat, specifically the DHA, with no major impact on growth performance and carcass traits.

Productive performance of Krškopolje pig breed – Review of preliminary results

Local pig breeds are adapted to specific local environment and fed with various locally available feedstuffs. Besides their genetic merit for agro-biodiversity, they represent the basis for sustainable local pork chains. The aim of the present study was to summarize data already available in the literature on production performance of Slovenian autochthonous pig breed - Krskopolje, which is one of the local pig breeds investigated in the project TREASURE. A collection and review of available literature data on productive traits (growth, carcass and meat quality) of Krskopolje pig breed was carried out. Literature review shows that growth rate of Krskopolje pigs from birth to slaughter is in average 492 g/day (339-637 g/day; n=6). In the studies described in the literature, slaughter was performed at the average age of 293 days (230-360 days; n=9) and 118 kg live weight (90-145 kg; n=7). Reported average dressing yield was 77.3% (71.7-80.2%; n=9) and lean meat content 43.5 % (37.5-47.8%; n=7). Backfat thickness measured at the level of the last rib was in average 38 mm (28-53 mm; n=11), whereas loin eye area and loin eye fat area were in average 32.6 and 33.0 cm2, respectively (23.2-41.7; n=5 and 27.7-42.2; n=4; respectively). In the studies reporting meat quality of Krskopolje pigs, pH 24 h post-mortem in Longissimus dorsi muscle was in average 5.46 (5.28-5.60; n=7), drip loss 48 h post-mortem reached 5.1% (3.9-6.7%; n=4) and intramuscular fat content averaged 3.5% (2.7-4.6%; n=6). Although studies on Krskopolje pig are scarce, current review gives the first insight on productive performance of this local pig breed.

Effetto della somministrazione di maltodestrine e destrosio con la dieta sulle prestazioni in vita e alla macellazione di suini maschi immunocastrati

This study aimed to verify previous research findings showing that feeding maltodextrins (M) and dextrose (D) leads to a reduction of voluntary feed intake in the Italian heavy pig. This may be interesting for immunocastrated pigs fed ad libitum (ad lib.), whose feed intake skyrockets after the 2nd vaccination, causing too fatty carcasses at slaughtering. Thirty-six male pigs (Italian Duroc x Italian Large White crossbred) received a double immunocastrating injection at 90 and 162 days of age. At 120 days, weighing 51.84+4.38 kg, the subjects were evenly housed in 9 boxes, fed ad lib. till the 2nd injection and then given, until slaughtering (197 days of age; 144.51±9.70 kg), one of the experimental diets: control diet, ad lib. (CL); control diet, restricted at 7.5% l.w.0.75 (CR); with MD (3.5 + 3.5%; adjusted for energy and protein), ad lib. (MD). The CR diet was introduced as the alternative choice to avoid too fatty carcasses. Compared to the restricted ones, pigs fed ad lib. (with or without MD) showed statistically higher (P<.01) ADG (1325 and 1325 vs 905 g/d), ADFI (4630 and 4637 vs 2760 g/d), feed:gain ratio (3.53 and 3.52 vs 3.11), and heavier carcasses (125.1 and 124.4 vs 113.2 kg; P<.01) with lower lean meat content (52.21 and 52.09 vs 55.83 %; P<.01). The results point out how immunocastrated pigs fed ad lib. showed similar rearing and slaughtering performance regardless of the inclusion of M and D in the diet.

Comparison of the content of lean meat in pigs on farm and slaughter line

Measurement of lean meat on slaughter line and formation of price on the basis significantly contribute to the overall improvement of the quality and profitability of production and distribution of pork. The content of lean meat on live pigs was measured on farm using ultrasound device PIGLOG 105. While in slaughterhouse, the content of lean meat measured using Fat-O-Meater (FOM), two-point method (TP) and partial dissection. 59.30% of lean meat in vivo was estimated by the apparatus PIGLOG-105 one day before slaughter. It is 0.91% more then partial dissection and when compared to FOM and TP it is more 4.86% and 4.02%. Great deviation between PIGLOG-105 on one side and FOM and TP on other side indicated some error, and then partial dissection solved this mystery. After this study, slaughterhouse constructed new formulas for FOM in pig carcass classification. Regarding that, slaughterhouses which used FOM or similar equipment for measuring percentage of lean meat, should control results of the equipment described in this study, minimum twice a year.

Reliability of breeding values for single and multi trait models of dam pig breed by direct inversion and approximation methods

Received: 2016-11-09 | Accepted: 2016-12-03 | Available online: 2017-12-31 http://dx.doi.org/10.15414/afz.2017.20.04.90-94 The objective of this study was to predict breeding values for single- and multi-trait animal models and compute their reliabilities using a direct inversion method (DIM), and single‑ (ST-APM) and multi-trait approximate methods (MT-APM). Variance and covariance components of lean meat (LM) content, average daily gain (ADG) from birth until the end of the field test, and number of piglets born alive at first (NBA1) and second and subsequent parities (NBA2), were estimated for the analyses of Czech Large White pigs (390,734 records), using single- and four-trait animal models. The average reliabilities estimated by DIM for all considered animals were 0.514 ±0.069, 0.406 ±0.070, 0.050 ±0.044, and 0.321 ±0.090 for LM, ADG, NBA1, and NBA2, respectively. Values of 0.576 ±0.087, 0.150 ±0.078, 0.228 ±0.078, and 0.323 ±0.099, were obtained for the ST-APM for LM, ADG, NBA1, and NBA2, respectively. The use of MT-APM slightly increases the reliability of breeding values by 4 %, 6 %, 14 %, and 8 % for LM, ADG, NBA1, and NBA2, respectively. In addition, the dependence of the reliability values on the number of offspring of breeding boars is obtained; the reliability increases from 0.215 for less than 5 offspring to 0.989 for more than 400 offspring for the LM trait. Calculated Pearson’s and Spearman’s correlation coefficients between the employed methods were, in general, high, positive, and highly statistically significant. The multi-trait approximation method can be used for the calculation of reliabilities of breeding values as an alternative for direct inversion method that has computational limitations Keywords: pig, breeding value, reliability, direct inversion, approximation References BAUER J., PŘIBYL J. and VOSTRÝ L. (2015) Contribution of domestic and Interbull records to reliabilities of single-step genomic breeding values in dairy cattle. Czech J. Anim. Sci. , 60, 6, pp. 263-267 GROENEVELD, E., M. KOVAC, and N. MIELENZ. (2008) VCE User’s Guide and Reference Manual, Version 6.0. Available from ftp://ftp.tzv.fal.de/pub/latest_vce/doc/ (accessed Aug 1, 2011). GROENEVELD E., KOVAC M. and WANG T. (1990) PEST, a general purpose BLUP package for multivariate prediction and estimation. In: Proc. 4th World Congr. Genet. Appl. Livest. Prod., Edinburgh, 13, pp. 488-491. KRUPA, E. and WOLF, J. (2013) Simultaneous estimation of genetic parameters for production and litter size traits in Czech Large White and Czech Landrace pigs. Czech J. Anim. Sci ., vol. 58, pp. 429–436. KRUPA, E., E. ŽAKOVA, and Z. KRUPOVA. (2015) Evaluation of inbreeding and genetic variability of five pig breeds in Czech Republic. Asian–Australas. J. Anim. Sci . vol. 28, pp. 25–36. MISZTAL, I., T. J. LAWLOR, and T. H. SHORT. (1993) Implementation of single- and multiple-trait animal models for genetic evaluation of Holstein type traits. J. Dairy Sci. , vol. 76, pp. 1421–1432. MISZTAL, I., and WIGGANS, G. R.. (1988) Approximation of prediction error variance in large-scale animal models. J. Dairy Sci., 71(Suppl. 2), pp. 27–32. MISZTAL, I. and PEREZ-ENCISO, P. (1993) Sparse Matrix Inversion for Restricted Maximum Likelihood Estimation of Variance Components by Expectation-Maximization. J. Dairy Sci ., 76, 5, pp. 1479-1483 MISZTAL I. et al. (2013) Methods to approximate reliabilities in single-step genomic evaluation. J. Dairy Sci ., vol. 96, pp. 647–654. MRODE R. A. (2005) Linear Models for the Prediction of Animal Breeding Values . 2nd Edition. Wallingford: CABI. MRODE R. A. (2014) Linear Models for the Prediction of Animal Breeding Values . 3rd Edition. Wallingford: CABI. NEUMAIER A., and GROENEVELD, E.. (1998) Restricted maximum likelihood estimation of covariances in sparse linear models. Genet. Sel. Evol ., vol. 30, pp. 3-26. SANCHEZ, J. P., MISZTAL, I. and J. K. BERTRAND. (2008) Evaluation of methods for computing approximate accuracies in maternal random regression models for growth trait in beef. J. Anim. Sci ., vol. 86, pp. 1057–1066. STRABEL, T., MISZTAL, I. and J. K. BERTRAND. (2001) Approximation of reliabilities for multiple-trait models with maternal effects. J. Anim. Sci., vol. 79, pp. 833–839. TIER, B. and MEYER, K. (2004) Approximating prediction error covariances among additive genetic effects within animals in multiple-trait and random regression models. J. Anim. Breed. Genetics, vol. 121, no. 2, pp. 77-89. VanRADEn P.M. (2008) Efficient methods to compute genomic predictions. J. of Dairy Sci., vol. 91, pp. 4414–4423. VanRADEN, P. M., and WIGGANS, G. R. (1991) Derivation, calculation, and use of national animal model information. J. Dairy Sci ., vol. 74, pp. 2737–2746. WIGGANS, G. R., MISZTAL, I. and van VLECK, L. D. (1988) Animal model evaluation of Ayrshire milk yield with all lactations, herd-sire interaction, and groups based on unknown parents. J. Dairy Sci ., vol. 71, pp. 1319–1329.

Culinary and technological suitability of pork obtained from three-way cross fatteners (Landrace x Yorkshire) x Duroc and (Landrace x Yorkshire) x Hampshire

The aim of the study was to evaluate the culinary and technological value of meat obtained from three-way cross fattening pigs, i.e. [Landrace (L) x Yorkshire (Y)] x Duroc (D) and [Landrace (L) x Yorkshire (Y)] x Hampshire (H). The study was carried out in spring and summer on 60 pigs divided in 2 genetic groups: (LxY) x D and (LxY) x H. The rearing and pre- and post-slaughter conditions were the same for all animals. Slaughter and post-slaughter handling of the carcasses was in accordance with the procedure in use at the meat plant. The research material was similar in terms of hot carcass weight (85.14 ±2.90 kg and 85.31 ±3.29 kg) and lean meat content (56.50 ±2.71% and 56.98 ±1.99%) within each genetic group, i.e. (LxY) x D and (LxY) x H. The significant, highly unfavourable means obtained for meat quality traits in the case of the (LxY) x H pigs, in terms of both culinary and technological suitability for processing, clearly indicates that the Hampshire breed should not be used as a paternal component in mass production of fatteners. In the case of the (LxY) x D fatteners, the highly favourable values for meat quality traits, of importance to both the consumer and the meat industry, clearly support the use of the Duroc breed as a paternal component.

Carcass characteristics and meat quality of bulls and steers slaughtered at two different ages

This study was conducted to evaluate animal performance, carcase characteristics and meat quality of young bulls and steers (Charolais × Holstein-Friesian), fattened until 15 and 18 months of age. One half of 40 young bulls were castrated at 2 or 3 weeks of age. Starting at 7 months of age, they received grass silage supplemented with concentrates. At the end of the fattening period, the animals were slaughtered, and carcase quality and the quality of meat from Musculus longissimus thoracis (MLT) were evaluated. Bulls had a higher carcase dressing percentage, and their carcases had higher lean meat content than steers. MLT from steers had higher intramuscular fat (IMF) content (by 0.89%); it was less tough, more tender and palatable. IMF from bulls had higher concentrations of polyunsaturated fatty acids (PUFAs) and a higher n-6/n-3 PUFA ratio than IMF extracted from steer meat. Older animals had higher carcase quality than those slaughtered at 15 months of age, and slaughtering at a later age had no negative influence on meat quality.

Meat Quality and Fatty Acid Profile of Pork and Backfat from an Indigenous Breed and A Commercial Hybrid of Pigs

Abstract The aim of this study was to verify the hypothesis that carcass traits, quality and oxidative stability of meat, and fatty acids profile in intramuscular fat (IMF) of M. longissimus lumborum et thoracis (MLLT) and backfat (BF) are different between the observed genotypes of pigs. A total of 64 animals were included in the experiment, 32 pigs of native breed Prestice Black-Pied breed (PBP) and 32 pigs of hybrid combination Large White × Landrace sows × Duroc × Pietrain boars (LWLDP). PBP pigs showed higher values of IMF (P≤0.01) and BF, lower lean meat content and drip loss value (P≤0.001) than the LWLDP hybrid. The value of pH45,24 was higher (P≤0.05) in PBP pigs. The analysis of fatty acid profile in MLLT showed higher content of C8:0 (P≤0.01), C10:0 (P≤0.01), C15:0 (P≤0.01), C22:0 (P≤0.05), C18:1 n-9 (P≤0.01), C18:3 n-6 (P≤0.001), C20:3 n-3 (P≤0.05), C20:4 n-6 (P≤0.01), C22:4 n-6 (P≤0.05), C22:5 n-3 (P≤0.01) and C22:6 n-3 (P≤0.01) in LWLDP than in PBP pigs. The opposite trend was observed in C18:1 n-9 (P≤0.01) and C20:5 n-3 (P≤0.01). Higher content of MUFA as well as the MUFA/SFA ratio were found in PBP breed (P≤0.01). Higher levels of C10:0 (P≤0.01), C12:0 (P≤0.01), C14:0 (P≤0.001), C16:0 (P≤0.001), C14:1 n-5 (P≤0.01), C16:1 n-7 (P≤0.05), C18:1 n-7 (P≤0.001), C20:5 n-3 (P≤0.01) and C22:6 n-3 (P≤0.05) in BF were found in LWLDP pigs, however the content of C24:1 n-9 (P≤0.01), C18:2 n-6 (P≤0.05), C18: n-3 (P≤0.05), C20:4 n-6 (P≤0.01) and C22:5 n-3 (P≤0.01) was higher in PBP pigs. SFA content was higher (P≤0.001) in LWLDP hybrid, but PUFA (P≤0.01), n-6 PUFA (P≤0.05) and mainly n-3 PUFA (P≤0.01) were higher in PBP pigs. In BF, the MUFA/SFA (P≤0.05) and PUFA/SFA (P≤0.001) ratios were higher in PBP pigs; on the contrary the MUFA/PUFA (P≤0.05) ratio was higher in LWLDP pigs.

Usefulness of pork meat quality classes criteria in assessing of its culinary value

The aim of the study was to determine the usefulness of criteria (pH, R1 and EC) used to determine pork quality classes (RFN, PSE, DFD and AM) in assessing culinary value characteristics of pork. The study was carried out on 320 fatteners from the mass population in the spring-autumn season. Rearing conditions, pre-slaughter handling and carcass handling were the same for all animals. The fatteners were similar in terms of hot carcass weight (87.09 ±4.05 kg) and lean meat content (56.68 ±3.01%). The statistically significant correlations found confirmed that basic pork quality criteria are suitable for assessment of selected parameters of culinary value that are important to the consumer. To obtain more precise conclusions regarding the suitability of basic pork quality criteria (pH1, pH24, pH48, R1, EC2 and EC24) for estimation of characteristics of culinary value, canonical analysis should be used to determine the relationships between two sets of variables: independent (basic criteria of pork quality classes) and dependent (basic culinary values of pork).

Analysis of the lifetime and culling reasons for AI boars

BackgroundThe aim of the study was to analyze the lifetime and culling reasons for boars used in insemination centers (AI centers).MethodsThe data collected from 355 culled boars from 1998 to 2013 included: age at start of semen collection, boar herd life, culling reason, daily gain and lean meat content, and number of ejaculates not meeting sales requirements after dilution. Culling reasons were divided into 7 groups: low semen value (LSV), low or lack of libido (LL), leg problems (LP), infectious diseases (ID), old age (OA), reduced demand for semen from the given boar (RD), and others (OT).ResultsThe most common culling reasons for boars were LSV (23.7%) and RD (22.5%). It was observed that the lowest daily gains were noted in boars culled due to OA. Boars culled due to OA and RD were maintained in production for the longest time (over 1000 d), for LSV and ID retention was about 700 d, and due to LL below 400 d. The survival probability was over 0.9 until 1.5 yr, and just over 0.2 until 4 yr. The highest relative frequency was observed in the 36th and 42nd mo of life (over 16%). Hazard risk analysis revealed a more than 10 times higher risk of culling in the case of LL, ID or OT, in comparison to OA.ConclusionsThe results can be used as a direct point of reference for the identification of emerging problems in AI boar exploitation and the development of an appropriate culling policy in AI centers.