Lean Meat Content Research Articles

The influence of housing and feeding systems on selected fattening and slaughter parameters of finishing pigs with different genotypes

The aim of the present study was to demonstrate the influence of housing and feeding systems on selected fattening and slaughter parameters of finishers with different genotypes. The experimental population consisted of 1200 finishers in three genetic variants from the Landrace (L), Large White (LW), Duroc (D) and Pietrain (P) breeds: 400 finishers L × [D × P] genotype, 400 finishers LW × [D × P] genotype and 400 finishers [L × LW] × [D × P] genotype. Subgroups were isolated for each genetic variant with the experimental factors: housing system (slatted floor or deep litter) and feeding system (dry or liquid). Selected fattening parameters were analysed: final liveweight (kg), mortality (%), average daily gain (g/day) and feed conversion ratio (kg/kg gain). Additionally, slaughter parameters were analysed: carcass weight (kg), height of longissimus dorsi (LD) muscle (mm), backfat thickness (mm) and lean meat content (%). The housing system strongly affected the final liveweight, average daily gain and carcass weight. To a lesser degree, this factor determined the mortality, feed conversion ratio, height of LD muscle, backfat thickness and lean meat content. The feeding system substantially affected almost all fattening parameters, except for the mortality. Statistical analysis of slaughter parameters showed that the impact of the feeding system was confirmed statistically only in terms of carcass weight. Genotype largely determined the final liveweight, average daily gain, carcass weight and lean meat content. Taking into account interactions of all factors, the most favourable effect in terms of production was to fattening four-way crossbreeds [L × LW] × [D × P] on slatted floors and fed by liquid feeding.

Fattening Performance of Bulls of three Breeds Fattened Semi-Intensively in the Kostanay Region

The aim of this study was to determine the effect of cattle breed on carcass traits and meat quality of bulls fattened semi-intensively and slaughtered at 18 months of age. The animals were divided into three experimental groups: Group AA - 16 Angus bulls, group WK - 19 Kazakh White headed bulls, group AK - 20 Kazakh Aulie-Ata bulls. All bulls were slaughtered at the end of the fattening period. Angus bulls had the highest (p≤0.05) final body weight (494.9 kg) at 18 months of age. Average daily gain was also highest (p≤0.01 and p≤0.05) in group AA (863 g). Angus bulls were characterized by the highest carcass dressing percentage (56.8%) and the highest fat content (3.4%). Carcass length and thigh circumference were significantly (p≤0.05) higher in AA bulls than in AK bulls. The content of lean meat and fat in the carcass was highest (79.4%, p≤0.05) in AA bulls and lowest in AK bulls. Samples of semitendinosus muscle collected from AA bulls had the highest content of dry matter (24.89%), protein (22.5%) and fat (2.27%, p≤0.05).

Effect of Birth Weight of Piglets on Their Growth Ability, Carcass Traits and Meat Quality

The objective of this study was to investigate the effect of birth weight on growth performance and carcass quality. Data were collected from 80 crossbred piglets. Individual body weight was measured at birth, at the age of 21, 28 and 38 days, 4 weeks before slaughter, 2 weeks before slaughter and one day before slaughter. Average daily weight gains in separate intervals were calculated. Fattening period was finished at the same day for all pigs. Lean meat percentage and pH1 value were measured after slaughter, drip loss and intramuscular fat content were analysed in laboratory. Data were divided into 4 groups according to the birth weight of piglets (I: less than 1000 g, II: 1001 – 1200 g, III: 1201 – 1500 g, IV: 1501 g and more). Increased birth weight resulted in increased daily weight gain from birth to weaning (28 days), after weaning and also from birth to slaughter (P ≤ 0.05, P ≤ 0.01). The high daily weight gain in group IV enabled pigs to reach the slaughter weight one month earlier than pigs from group II. The lowest lean meat content (52.74 ± 2.82 %) was found in group IV. This is connected with high slaughter weight (132.50 ± 7.27 kg). Intramuscular fat content, pH1 value and drip loss were not affected by birth weight of piglets.

A genome-wide association analysis for carcass traits in a commercial Duroc pig population.

We performed a genome-wide association study to map the genetic determinants of carcass traits in 350 Duroc pigs typed with the Porcine SNP60 BeadChip. Association analyses were carried out using the gemma software. The proportion of phenotypic variance explained by the SNPs ranged between negligible to moderate (hSNP2=0.01-0.30) depending on the trait under consideration. At the genome-wide level, we detected one significant association between backfat thickness between the 3rd and 4th ribs and six SNPs mapping to SSC12 (37-40Mb). We also identified several chromosome-wide significant associations for ham weight (SSC11: 51-53Mb, three SNPs; 67-68Mb, two SNPs), carcass weight (SSC11: 66-68Mb, two SNPs), backfat thickness between the 3rd and 4th ribs (SSC12: 21Mb, one SNP; 33-40Mb, 17 SNPs; 51-58Mb, two SNPs), backfat thickness in the last rib (SSC12: 37Mb, one SNP; 40-41Mb, nine SNPs) and lean meat content (SSC13: 34Mb, three SNPs and SSC16: 45.1Mb, one SNP; 62-63Mb, 10 SNPs; 71-75Mb, nine SNPs). The ham weight trait-associated region on SSC11 contains two genes (UCHL3 and LMO7) related to muscle development. In addition, the ACACA gene, which encodes an enzyme for the catalysis of fatty acid synthesis, maps to the SSC12 (37-41Mb) region harbouring trait-associated regions for backfat thickness traits. Sequencing of these candidate genes may help to uncover the causal mutations responsible for the associations found in the present study.

The Effect of Crossing the Native Złotnicka Spott Ed Pigs with Other Breeds on Slaughter Value of Fatt Eners and Quality of Dry-Cured Meat Products

Abstract The dry-cured necks and hams produced from the meat of Złotnicka Spotted (ZS) pigs and their crossbreds with Duroc and Polish Large White, were tested. The slaughter value of the fatteners was determined (lean meat content, backfat thickness, area of the loin cross-section). The water, fat, protein and NaCl content was established in the final products. The meat colour (L* a* b*) and pH were measured. The final products were subjected to sensory evaluation and ranked on the scale of 1-5 points. Crossing the Złotnicka Spotted with the PLW resulted in higher lean meat content by approx. 4 percentage points (p.p.) and in thinner back fat thickness by 0.6 cm. Dry-cured ham produced from the meat of different fattener groups did not differ significantly in terms of physico-chemical traits as well as sensory traits. The sensory characteristics of both ham and neck received high scores (on average above 4.5 points). It was found that the tested products differed in terms of chemical content. The dry-cured necks contained approx. 19.45% of fat in the group of the ZS × PLW crossbreds whereas in other groups this figure was 2 to 6 p.p. higher. The dry-cured ham that was produced was based on the meat of purebred pigs containing 3 to 4.6 p.p. less fat compared to the crossbreds with the Duroc. The research proved that crossing the ZS with PLW and Duroc did not make the quality of the dry-cured products deteriorate.

Productivity of pigs of conservation breeds in terms of selected gene polymorphisms

The material for the analyses comprised blood samples collected from 65 Zlotnicka Spotted (Zlp) sows and 43 Zlotnicka White (Zlb) sows born and kept in two herds in Wielkopolska. While analysing reproductive, fattening and slaughter traits, information was collected on 290 litters, including 180 litters of Zlp sows and 110 litters of Zlb sows. Intravital measurements were taken using a Piglog 105 for the evaluation of the mean backfat thickness, lean meat content and loin eye thickness. The aim of the research was to determine the effect of selected genotypes on reproductive, fattening and carcass performance traits of the two indigenous pig breeds (Zlotnicka White and Zlotnicka Spotted), kept and bred in Poland. The frequency of RYR1 genotypes indicates that the number of animals with the RYRTT genotype carrying a mutation in the RYR1 gene was low in the Zlotnicka breeds. In the herd of Zlb sows, a statistically significant negative effect of the RYRCT genotype on piglet wastage up to 21 days of age was found. The highest wastage rate was recorded in the group of heterozygotes. The frequency of the genotypes indicates that the DD genotype typical of animals with polymorphism in the GH/MspI gene occurred rarely in the analysed population of the Zlotnicka breeds. A statistically significant effect of the GH/MspI genotype on litter weight at 21 days of age was observed in the population of the Zlb sows. The heaviest piglets were born to sows with the DD genotype, while the lightest piglets were born to sows with the CC genotype. The frequency of the LEP genotypes indicates that the number of animals with the TT genotype was very low in the population of the Zlb pigs. No animal with the TT genotype was found in the Zlp herd.

Estimation of genetic parameters for teat number and reproduction and production traits from different data sources for Czech dam breeds

Genetic parameters for total number of teats (TNT), total number of piglets born (TNB), number of weaned piglets (NW), lean meat content, and average daily gain were estimated for the populations of Czech Large White and Czech Landrace pig breeds. TNT was defined as sum of all measurable teats without taking into account of between teats and was counted during the identification of piglets up to 10 days after birth. Two main resources of data for TNT were analyzed: (1) TNT recorded only for breeding pigs in the national performance testing scheme (animals with at least 14 teats in total) as the pre-selected performance data set (PT; 94,500 animals); and (2) TNT recorded in nucleus and multiplier farms (F). In this data set (40,160 animals), whole litter information, including negatively selected piglets, was considered. Only 6.7% of animals from farmers’ data set showed optimal production in the performance test. The average number of piglets evaluated in the PT and F data sets per litter was 2.7 and 9.4, respectively. The TNT was analyzed using single-trait and five-trait animal models by using production and reproduction data to determine heritability and genetic correlations between TNT and production and reproduction traits. As expected, the farmers’ data set was characterized by higher variability of TNT than the performance data set. The estimated heritability for TNT ranged from 0.28 to 0.30 (regarding the data and models used). The genetic correlations of TNT with production and reproduction traits were negligible and varied from −0.096 to 0.080 depending on the datasets and models used. A very high significant genetic correlation (0.782 and 0.793) was found between TNB and NW. Our hypothesis of impact of raw data inclusion on estimated genetic parameters for the trait TNT was rejected. Our findings suggested no significant differences for the estimated heritabilities of TNT among the analyzed datasets and models. The breeding values for TNT can be estimated by using single as well as multi-trait animal models, because no genetic correlations with production and reproduction traits were found.

Identification of genes in longissimus dorsi muscle differentially expressed between Wannanhua and Yorkshire pigs using RNA-sequencing.

Western commercial pig breeds have been intensively selected, resulting in a sizeable, rapid and efficient accretion of muscle but a reduction in meat quality. When compared with Western commercial pig breeds, Chinese indigenous pig breeds exhibited slower growth rates and reduced lean meat content but superior perceived meat quality. To study the factors that determine meat quality, we examined piglets of one Western commercial breed (Yorkshire) and one Chinese indigenous breed (Wannanhua) and sequenced the longissimus dorsi muscle using RNA-sequencing (RNA-seq). We analyzed their transcriptomes, focusing on identifying candidate genes that may influence porcine muscle growth, meat quality and adipose deposition. Gene Ontology functional enrichment and pathway enrichment analyses identified differentially expressed genes (DEGs) primarily associated with glycolytic metabolism, biological processes of muscle development and signaling pathways related to fatty acid metabolism, growth and carcass traits. This finding suggests that the DEGs may play important roles in determining meat quality traits. Quantitative real-time reverse transcription polymerase chain reaction confirmed the differential expression of 12 selected DEG. This study identified a number of novel candidate genes for porcine meat quality and carcass traits that merit further investigation to elucidate the molecular mechanisms responsible for muscle growth and fat deposition.

Accuracy of estimating the technological and economic value of pig carcass primal cuts with an optical-needle device

The aim of this study was to demonstrate the possibility of using CGM-device measurements for the precise estimation of lean-meat content, the real technological and economic value of ham and loin. The experiment was carried out in two stages: the dissection (n = 136) and the industrial cutting (n = 298). Lean-meat content in carcasses was defined with a CGM device, where the thicknesses of the musculus longissimus dorsi (M2) and backfat (with the skin) (T2) were measured. The strongest correlations were achieved for the T2 measurement and the share of skin with fat or muscles in ham and loin. The strongest correlations for M2 were noted for muscle content in ham and loin. Measurements for M2 positively correlated with all the elements of the technological cutting of ham and loin, but negatively with T2 measurements, in terms of commercial value. The highest values, regardless of the point of measurement, were noted for boneless loin (loin) and ham 4D (ham). The highest estimating accuracy was noted for dissection and technological cutting of loin compared with ham. The results of the study suggest that the current classification device should be modified and improved for the evaluation of the real commercial value of the carcass.

The effect of sex, carcass mass, back fat thickness and lean meat content on pork ham and loin characteristics

Abstract. This study was designed to determine the ratio of ham and loin in half-carcasses and the tissue composition of these cuts. The research material consisted of 140 pig carcasses. The experimental materials were derived from the Polish commercial population of fattener pigs. Genetic material representing the most commonly slaughtered fatteners in Poland. Fatteners for the study came from several suppliers. All fatteners were kept in similar farms complying with principles of animal welfare. The right half-carcasses were divided into different groups, regardless of sex, half-carcass mass, back fat thickness and lean meat content class. Ham and loin obtained from carcasses were subjected to a detailed dissection, and the percentage of ham and loin in the carcass and the overall percentage of of the cuts in relation to the entire half-carcass were calculated. Gilts were characterized by a higher content of ham in half-carcasses than barrows (P ≤ 0.01). The increase in back fat thickness reduced the content of ham in half-carcasses and increased the content of loin (P ≤ 0.01). A similar trend was shown for the lean meat content class parameter. Additionally, interaction (P ≤ 0.01) between back fat thickness and meat content with respect to the percentage content of loin in carcasses was noted. Gilts were characterised by about a 1.38 % higher proportion of muscles in the ham (P ≤ 0.05) and a 0.47 % lower proportion of intermuscular fat (P ≤ 0.01). An average increase of five point in back fat thickness increases the amount of subcutaneous fat with skin (P ≤ 0.01) and intermuscular fat (P ≤ 0.01) and reduces muscle (P ≤ 0.01) and bone (P ≤ 0.05 and P ≤ 0.01) levels. The interaction of percentage content of muscles in ham was observed (P = 0.04). The meat content class of carcasses did not only affect the level of bones in ham. It was confirmed that sex affected all the analysed dissection elements of the loin. Back fat thickness and meat content classes were present in almost identical amounts in loin tissues (P ≤ 0.05 and P ≤ 0.01). Half-carcass mass showed a strong negative correlation with bone content in ham and loin (r = −0.35 and r = −0.21, respectively). Back fat thickness and meat content strongly and inversely correlated with the content of ham and loin in half-carcasses (r = −0.41 and r = 0.59 for back fat thickness; r = 0.66 and r = −0.57 for lean meat content). Close and inverse correlations of back fat thickness and lean meat content were observed with regard to their content in ham and loin (P ≤ 0.01).

The effect of growth rate and lean meat content in Pietrain×Duroc and Duroc×Pietrain hybrid boars on their semen characteristics

The aim of the study was to determine the effect of growth rate and lean meat content in Pietrain×Duroc and Duroc×Pietrain hybrid boars on their semen characteristics. On the basis of the results of performance testing carried out on the 180 day of life, the boars were divided into four groups according to their daily weight gain (I: 750–800 g; II: 801–850 g; III: 851–900 g; and IV: >900 g), and additionally into three groups according to lean meat content (I: 60–61%; II: 62–63%; and III: >63%). Ejaculates were evaluated for the following characteristics: volume, sperm concentration, percentage of sperm with progressive movement, number of sperm with progressive movement per ejaculate and per insemination dose, primary morphological defects and number of insemination doses obtained per ejaculate. Neither high daily weight gain in the hybrid boars during the rearing period nor their high lean meat content had a negative effect on their semen characteristics.

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The aim of this study was to evaluate whether the supplementation of conjugated linoleic acid (CLA) in feed mixtures influences the parameters of production performance in gilts. The experimental work was realized in operating conditions of a production pig farm. Total number of 40 gilts (20 gilts in control group and 20 gilts in experimental group) of hybrid combination Czech Large White x Czech Landrace (CLW x CL) were included in the observation. During the experiment the gilts kept for rearing were fed with a control compound feed and an experimental compound feed suplemented with 2% of CLA for the time of 65 days. At the beginning and the end of the experiment, performance tests were conducted in accordance with the methodology of CSN 466164 on Performance and progeny testing in pigs. The gilts in the experimental group reached higher weight 148.05 ± 15.80 kg versus 135.75 ± 17.60 kg (P < 0.05) at the end of the test. The evaluation of mean achieved daily gain for the time from birth to the end of the test confirmed higher values for the gilts in the experimental group 586.05 ± 66.64 g*day-1 against 539.00 ± 62.19 g*day-1 for the gilts in the control group (P < 0.05). Within other parameters of efficiency in gilts, i.e. lean meat content, backfat thickness and depth of MLLT muscle, no significant influence of CLA on their phenotypic manifestation was found. The results of study indicate, that the supplementation of feed mixture for rearing gilts with conjugated linoleic acid can influence the growth ability of gilts.

Immunocastrated male pigs: effect of 4 v. 6 weeks time post second injection on performance, carcass quality and meat quality

Immunocastration or vaccination against boar taint can be used as alternative for surgical castration of male piglets. The vaccine is administrated twice. After the second vaccination (V2), the pigs behave like barrows instead of boars and their feed intake increases which may result in a lower lean meat percentage. The timing of V2 is therefore crucial to find the right balance between the advantages of entire males and barrows. In this study, we evaluated the effect of time post second injection within the advised time frame (4 v. 6 weeks before slaughter) on behaviour, performance, carcass and meat quality of immunocastrated male pigs. In total, 180 animals (hybrid sow×Piétrain): 60 gilts, 60 male pigs vaccinated 6 weeks before slaughter (IM-6) and 60 male pigs vaccinated 4 weeks before slaughter (IM-4), all slaughtered at comparable slaughter weights. After 20 weeks of age, IM-6 showed more inactive behaviour at the expense of playing and aggressive behaviour. Daily feed intake (DFI), daily gain (DG) and feed conversion ratio (FCR) did not differ significantly between IM-6 and IM-4. Gilts had a lower DFI and DG in the late finishing phase and a higher FCR overall compared with both IM groups. Gilts showed a higher lean meat content compared with both IM groups. Earlier vaccination increased dressing percentage, which could partly be explained by the lower weight of the gastrointestinal tract, but not by testes weight. Meat quality traits and palatability did not differ significantly between IM-6 and IM-4. Vaccination of immunocastrates at 6 compared with 4 weeks before slaughter improved the calmness in the stable and the dressing percentage, while maintaining performance and carcass characteristics.

Carcass Traits and Meat Quality of Prestice Black-Pied Pig Breed

The objective of the study was to evaluate fattening performance, carcass value and meat quality in pigs of Prestice Black-Pied breed in relation to slaughter weight (SW) and gender (barrows and gilts, resp.). Pigs were divided into weight categories: SW1 (75 to 99.9 kg), SW2 (100 to 109.9 kg) and SW3 (110 to 130 kg) and all individual traits were analyzed by the general linear model procedure (SAS 9.3). Average SW of each weight group was as follows: SW1 94.2 kg, SW2 105.8 kg, and SW3 115.2 kg. Differences among average backfat thickness of 36.07 mm in SW1, 40.16 mm in SW2, and 43.21 mm in SW3 were significant (p<0.01). Lean meat content was 48.94% (SW1), 48.78% (SW2), and 48.76% (SW3). Pigs were slaughtered at average weight of 105.7 kg for barrows and 104.4 kg for gilts. Average backfat thickness for barrows was 40.90 mm and 38.72 mm for gilts (significant difference p<0.05). Lean meat content was 48.75% in barrows and 48.91% in gilts. The values of pH45, characterizing the meat of very good quality. The loin in SW3 was darker than the muscles of SW1 and SW2. Drip loss was the lowest in SW1 (1.96%), compared to the highest drip loss in SW3 (2.59%). Content of intramuscular fat was 2.68% in SW3, 2.79% in SW2, and SW1 had the lowest content 2.47%. The values of pH45, colour lightness and drip loss were similar in both genders. However barrows had higher intramuscular fat content by 0.31% than gilts (p<0.05).

Development of ZP Method for Seurop Pig Carcass Grading in Poland

Abstract In the present study, ZP method for lean meat content (LMC) evaluation in pig carcasses was tested. The experiment was carried out on 141 pigs selected from animals delivered for slaughter to the SKIBA S.A. meat plant located in Chojnice. The selected pigs originated from three country regions, and differed in respect of subcutaneous fat thickness (7-32 mm), carcass weight (60-120 kg) and sex (50% gilts and 50% castrated males). The main result of the study was a rectilinear regression equation for lean meat content assessment. Two linear measurements were used in the equation, i.e. backfat thickness measured on sacral vertebra and thickness of the muscle layer located between the beginning of the cross section of gluteus medius and back edge of the spinal cord. The evaluation error RMSEP was 2.33% and did not exceed the limit defined in EU regulations. Based on the Commission Decision 2011/506/EU the ZP method was approved to be used for pig carcass grading in Poland. A special measuring template was developed for the industrial use of the ZP method.

Exploring causal networks underlying fat deposition and muscularity in pigs through the integration of phenotypic, genotypic and transcriptomic data.

BackgroundJoint modeling and analysis of phenotypic, genotypic and transcriptomic data have the potential to uncover the genetic control of gene activity and phenotypic variation, as well as shed light on the manner and extent of connectedness among these variables. Current studies mainly report associations, i.e. undirected connections among variables without causal interpretation. Knowledge regarding causal relationships among genes and phenotypes can be used to predict the behavior of complex systems, as well as to optimize management practices and selection strategies. Here, we performed a multistep procedure for inferring causal networks underlying carcass fat deposition and muscularity in pigs using multi-omics data obtained from an F2 Duroc x Pietrain resource pig population.ResultsWe initially explored marginal associations between genotypes and phenotypic and expression traits through whole-genome scans, and then, in genomic regions with multiple significant hits, we assessed gene-phenotype network reconstruction using causal structural learning algorithms. One genomic region on SSC6 showed significant associations with three relevant phenotypes, off-midline10th-rib backfat thickness, loin muscle weight, and average intramuscular fat percentage, and also with the expression of seven genes, including ZNF24, SSX2IP, and AKR7A2. The inferred network indicated that the genotype affects the three phenotypes mainly through the expression of several genes. Among the phenotypes, fat deposition traits negatively affected loin muscle weight.ConclusionsOur findings shed light on the antagonist relationship between carcass fat deposition and lean meat content in pigs. In addition, the procedure described in this study has the potential to unravel gene-phenotype networks underlying complex phenotypes.

The influence of compound feed enrichment with rapeseed and linseed cake on the meat characteristics and fatty acids composition of beef bulls

The trial was conducted with Lithuanian Black-and-White bulls of 10 to 16 months age. The bulls were divided into analogous groups according to their origin, age and weight. During the trial the bulls in both groups were offered the same amount of maize silage, clover-oat-pea mixture silage and compound feed, the only difference being the composition of compound feeds. The aim of the study was to investigate the effects of compound feeds containing rapeseed and linseed cake and different amounts of n-6 and n-3 fatty acids on the fatty acid pattern in the longest muscle of the back (Musculus longissimus dorsi) meat of Lithuanian Black-and-White fattening bulls. Fatty acids n-6:n-3 ratio in rapeseed cake was 2.75, and that in linseed cake 0.25. More favourable ratio in linseed cake was determined by higher content of linolenic acid (C18:3n-3). Different feeding of bulls as regards rapeseed and linseed cake, fatty acid content and n-6:n-3 ratio had no significant influence on the weight of bulls prior to slaughter, carcass weight and yield, lean meat content and fatness grades. According to the SEUROP carcass classification system, the carcasses in both groups of bulls met the requirements for lean meat content O and fatness 2 grades. The study indicated that ground beef contained 49.93% higher (P < 0.05) content of linolenic acid (C18:3n-3) when the animals were fed compound feed with linseed cake and, therefore, higher n-6:n-3 ratio was influenced by a higher content of this acid in the feed. The study also indicated that total n-3 fatty acid content was 1.3 times greater and n-6 to n-3 fatty acid ratio was found 1.5 times lower (P < 0.05) in M. longissimus dorsi when feeding bulls linseed cake.

The economic and environmental value of genetic improvements in fattening pigs: An integrated dynamic model approach1

The selection of animals for improved performance affects the profitability of pig fattening and has environmental consequences. The goal of this paper was to examine how changes in genetic and market parameters impact the biophysical (feeding patterns, timing of slaughter, nitrogen excretion) and economic (return per pig space unit) results describing pig fattening in a Finnish farm. The analysis can be viewed as focusing on terminal line breeding goals. An integrated model using recursive stochastic dynamic programming and a biological pig growth model was used to estimate biophysical results and economic values. Combining these models allowed us to provide more accurate estimates for the value of genetic improvement and, thus, provide better feedback to animal breeding programs than the traditional approach, which is based on fixed management patterns. Besides the benchmark scenario, the results were simulated for 5 other scenarios. In each scenario, genotype was improved regarding daily growth potential, carcass lean meat content, or the parameters of the Gompertz growth curve (maturing rate [], adult weight of protein [α], and adult weight of lipid mass []). The change in each parameter was equal to approximately 1 SD genetic improvement (ceteris paribus). Increasing , , daily growth potential, or carcass lean meat content increased the return on pig space unit by €12.60, €7.60, €4.10, or €2.90 per year, respectively, whereas an increase in decreased the return by €3.10. The genetic improvement in and resulted in the highest decrease in nitrogen excretion calculated in total or per kilogram of carcass gain but only under the optimal feeding pattern. Simulated changes in the Gompertz growth function parameters imply greater changes in ADG and lean meat content than changes in scenarios focusing on improving ADG and lean meat content directly. The economic value of genetic improvements as well as the quantity of nitrogen excreted during the fattening period largely depends on feeding. Improved genotypes can require changes in pig management pattern. Estimating the influence of the genotype on the nitrogen excretion without considering changes in the management pattern can result in flawed conclusions. To improve overall economic performance and to decrease the environmental footprint of fattening pig production, the pig producer can adjust the herd management pattern according to the pigs' genetics.

Development Of An Econometric Model Case Study: Romanian Classification System

Abstract The purpose of the paper is to illustrate an econometric model used to predict the lean meat content in pig carcasses, based on the muscle thickness and back fat thickness measured by the means of an optical probe (OptiGrade PRO).The analysis goes through all steps involved in the development of the model: statement of theory, specification of the mathematical model, sampling and collection of data, estimation of the parameters of the chosen econometric model, tests of the hypothesis derived from the model and prediction equations. The data have been in a controlled experiment conducted by the Romanian Carcass Classification Commission in 2007. The purpose of the experiment was to develop the prediction formulae to be used in the implementation of SEUROP classification system, imposed by European Union legislation. The research methodology used by the author in this study consisted in reviewing the existing literature and normative acts, analyzing the primary data provided by and organization conducting the experiment and interviewing the representatives of the working team that participated in the trial.

Meat alternatives: life cycle assessment of most known meat substitutes

Food production is among the highest human environmental impacting activities. Agriculture itself accounts for 70–85 % of the water footprint and 30 % of world greenhouse gas emissions (2.5 times more than global transport). Food production’s projected increase in 70 % by 2050 highlights the importance of environmental impacts connected with meat production. The production of various meat substitutes (plant-based, mycoprotein-based, dairy-based, and animal-based substitutes) aims to reduce the environmental impact caused by livestock. This article outlined the comparative analysis of meat substitutes’ environmental performance in order to estimate the most promising options. The study considered “cradle-to-plate” meal life cycle with the application of ReCiPe and IMPACT 2002+ methods. Inventory was based on literature and field data. Functional unit (FU) was 1 kg of a ready-to-eat meal at a consumer. The study evaluated alternative FU (the equivalent of 3.75 MJ energy content of fried chicken lean meat and 0.3 kg of digested dry matter protein content) as a part of sensitivity analysis. Results showed the highest impacts for lab-grown meat and mycoprotein-based analogues (high demand for energy for medium cultivation), medium impacts for chicken (local feed), and dairy-based and gluten-based meat substitutes, and the lowest impact for insect-based and soy meal-based substitutes (by-products allocated). Alternative FU confirmed the worst performance of lab-grown and mycoprotein-based analogues. The best performing products were insect-based and soy meal-based substitutes and chicken. The other substitutes had medium level impacts. The results were very sensitive to the changes of FU. Midpoint impact category results were the same order of magnitude as a previously published work, although wide ranges of possible results and system boundaries made the comparison with literature data not reliable. The results of the comparison were highly dependable on selected FU. Therefore, the proposed comparison with different integrative FU indicated the lowest impact of soy meal-based and insect-based substitutes (with given technology level development). Insect-based meat substitute has a potential to be more sustainable with the use of more advanced cultivation and processing techniques. The same is applicable to lab-grown meat and in a minor degree to gluten, dairy, and mycoprotein-based substitutes.