Meat quality comparison of Berkshire, Duroc and crossbred pigs sired by Berkshire and Duroc

Comparison of Carcass Characteristics and Meat Quality between Duroc and Crossbred Pigs

This study was conducted to compare the carcass characteristics and meat quality characteristics of Duroc breed and crossbred pigs (Landrace × Yorkshire × Duroc, LYD). Duroc and crossbred pigs did not show differences in carcass characteristics. Crossbred pigs had higher moisture and protein content than Duroc breeds. However, Duroc breeds had a higher fat content than the crossbred pigs. In meat quality characteristics, crossbred pigs showed higher values of drip loss and cooking loss over Duroc breeds, while Duroc breeds showed higher ultimate pH value compared to that of crossbred pigs. However, there were no differences in water holding capacity and shear force value. In myoglobin content, crossbred pigs had higher content compared to that in the Duroc population. In subjective evaluation and sensory characteristics, Duroc breeds showed significantly higher scores in all categories except for tenderness over the crossbred pigs. However, in storage characteristics, Duroc breeds showed reduced tendency relative to crossbred pigs. Crossbred pigs had higher unsaturated fatty acid content than Duroc breeds did. In these results, Duroc breeds showed excellent meat quality characteristics with its higher intramuscular fat content and pH value, lower drip loss and cooking loss and higher juiciness and flavor, compared to the crossbred pigs.

Quality Comparison of Pork Loin and Belly from Three-way Crossbred Pigs during Postmortem Storage

This study was performed to determine the meat quality characteristics of pork loin and belly from 3 different three-way crossbred pigs: Yorkshire × Landrace × Duroc (YLD), Yorkshire × Chester White × Yorkshire (YCY), and Yorkshire × Berkshire × Duroc (YBD). Each of the twenty crossed pigs were randomly selected with their live weights at the range of 110-120 kg. After being slaughtered and cooled at 0℃ for 24 h in a chilling room, the parts of loin and belly on the left side of the cooled carcasses were cut and prepared for analysis. The intramuscular fat contents of the loins from YLD were higher than those of the other crossbreds (p<0.05), and the YCY bellies had the highest moisture contents (p<0.05). Water holding capacity (WHC) of the loins from YCY were higher than the other crossbreds (p<0.05). Shear force values of the YBD loins were higher than the others (p<0.05). The TBARS values of YCY loins were significantly lower than the others at 0 d, but the difference disappeared after 14 d of storage. Sensory scores of YLD were ranked higher than the YCY or YBD in both the loins and bellies (p<0.05). The relatively high sensory values of YLD crossbred pork could be explained by the better WHC, the low shear forces, and the higher fat contents. The results indicated that the meat qualities could be altered by three-way crossbreeding.

Effect of reducing and replacing pork fat on the physicochemical, instrumental and sensory characteristics throughout storage time of small caliber non-acid fermented sausages with reduced sodium content

The effect of pork fat reduction (from 44% to 20% final fat content) and its partial substitution by sunflower oil (3% addition) on the physicochemical, instrumental and sensory properties throughout storage time of small caliber non-acid fermented sausages (fuet type) with reduced sodium content (with partial substitution of NaCl by KCl and K-lactate) and without direct addition of nitrate and nitrite (natural nitrate source used instead) was studied. Results showed that sausages with reduced fat (10% initial fat content) and with acceptable sensory characteristics can be obtained by adding to the shoulder lean (8% fat content) during the grinding, either 3.3% backfat (3% fat content) or 3% sunflower oil, both previously finely comminuted with lean. Furthermore, sunflower oil showed to be suitable for partial pork backfat substitution in very lean fermented sausages, conferring desirable sensory properties similar to those of sausages with standard fat content. The sensory quality of the sausages was maintained after three-month cold storage in modified atmosphere.

Fatty acid composition in hybrid pigs as based on local fatty Lithuanian breed and wild boar

The study was designed to investigate the fatty acid composition in longissimus dorsi (LD) and semimembranosus muscles (SM) and subcutaneous tissue of hybrid (1/4 Lithuanian indigenous wattle, 1/4 wild boar and 1/2 Yorkshire or 1/2 Landrace) pigs. The SM showed a tendency to have lower contents of monounsaturated fatty acids (MUFA) and higher contents of polyunsaturated fatty acids (PUFA) than the LD muscle. No statistically significant differences were observed between the muscles in lipid quality indices, i.e., atherogenic (AI) and thrombogenix (TI) indices and the ratio of hypocholesterolemic and hypercholesterolemic fatty acids (h/H). In the SM, the content of PUFA from Yorkshire-sired hybrids was relatively 47.8% higher, including C18:2n-6, C20:4n-6 and DPA (C22:5n-3) that were higher, respectively, by 44.3%, 86.6% and 51.6% in comparison with those from Landrace-sired hybrids. The gilts had a lower content of MUFA, including C18:1 and C20:1n-9 fatty acids in the LD muscle and tended to have a higher content of PUFA in the SM compared to the barrows. Neither the terminal breed in crossing, nor the gender had any significant effects on the proportions of total saturated, MUFA and PUFA in the subcutaneous tissue.

Effect of the type of fat on the physicochemical, instrumental and sensory characteristics of reduced fat non-acid fermented sausages

Four batches of reduced fat non-acid fermented sausages were manufactured with pork-ham lean, and the addition of no fat (Lean), 5% pork backfat (BF), 5% sunflower oil (SO) and 5% diacylglycerols (DAGs). The effect of the type of fat as pork-fat substitute on some physicochemical parameters, instrumental color and texture and sensory attributes of the sausages was studied. Results showed that reduced fat non-acid fermented sausages containing less than 12.5% of fat (BF, SO and DAGs) had a good overall sensory quality. This means a fat reduction of more than 70% compared with the average fat content of standard fermented sausages of similar characteristics. Sausages with SO showed higher sensory ratings in desirable ripened odor and flavor attributes and improved texture defined by lower hardness and chewiness (both sensory and instrumental) and higher crumbliness. Sausages with DAGs showed a similar behavior to that of BF, so they could be a good alternative to produce healthier reduced fat non-acid fermented sausages.

Effects of genotype and dietary oil supplementation on performance, carcass traits, pork quality and fatty acid composition of backfat and intramuscular fat

A 42-day study was conducted to evaluate the effect of genotype: terminal sire line Duroc×F1 (DC×F1); terminal sire line Embrapa MS-115×F1 (MS-115×F1); and MS-115×Moura (MS-115×MO) and three dietary oil sources: soybean; canola; and canola+flax, on performance, carcass traits, pork quality, and fatty acid composition. Genotype affected the technological quality of pork and fatty acid profile. MS-115-sired pigs had better meat color and Duroc-sired pigs had higher intramuscular fat content, more saturated fat and better omega-6/omega-3 ratio. Moura breed influenced positively meat tenderness and intramuscular fat. Diet did not affect the technological quality of the meat. Canola or canola+flax oil diet supplementations increased monounsaturated and C18:3 and decreased C18:2 fatty acids, reducing the omega-6/omega-3 ratio. The best omega-6/omega-3 ratio was obtained through supplementation with canola+flax.

Association of the gene encoding stearoyl-CoA desaturase (SCD) with fatty acid composition in an intercross population between Landrace and Korean native pigs

Fatty acid (FA) composition is one of the most important parameters for the evaluation of meat quality. The stearoyl-CoA desaturase (SCD) gene is considered a positional candidate gene affecting FA composition in SSC14, based on previous quantitative trait loci studies. To evaluate the association of the SCD gene with FA composition in a Korean native pig × Landrace F(2) intercross population, we genotyped six single nucleotide polymorphisms (SNPs) of the SCD gene located in promoter region [2 SNPs (g.-353T>C, g.-233T>C)], exonic region [1 SNP (g.817C>T) in exon 2] and 3' UTR [3 SNPs (g.13311C>G, g.14384G>A, and g.14424C>T)] identified by massively parallel sequencing technology. Eighteen FA composition traits were measured in more than the 950 F(2) animals. A mixed-effect model was used to evaluate associations between these SNPs and FA composition traits in the F(2) intercross population. A detailed investigation detected that the five FA composition traits [palmitoleic acid (C16:1), stearic acid (C18:0), arachidic acid (C20:0), saturated FA, and unsaturated FA] were highly significant (P < 4.7 × 10(-5); C20:0) in association with the SNP g.-233T>C, SNP g.817C>T, SNP g.13311C>G and SNP g.14384G>A in the SCD gene, whereas SNP g.14424C>T was only significantly associated with palmitoleic acid (C16:1, P = 1.4 × 10(-3)). No significant association of FA composition traits with SNP g.-353T>C was detected. In particular, the SNP g.14384G>A accounted for 30.6 % of the additive genetic variance of palmitoleic acid (P = 1.9 × 10(-10)). These results suggest the SCD gene has a strong effect on FA composition in the crossbred pig population.

Comparison of pork quality and sensory characteristics for antibiotic free yorkshire crossbreds raised in hoop houses

The objective of this study was to compare pork characteristics and to determine consumer acceptability of pork chops from antibiotic free Yorkshire crossbreds sired by Berkshire (BY), Large Black (LBY), Tamworth (TY) or Yorkshire (YY) boars and reared in hoop houses. The experiments were conducted at the North Carolina Agricultural and Technical State University (NCA&TSU) Farm in Greensboro, NC and the Cherry Research Station Center for Environmental Farming Systems (CEFS) Alternative Swine Unit in Goldsboro, NC (source of antibiotic free Yorkshire sows used at both places). Twenty-four sows were artificially inseminated at each location in each of three trials. Litters were weaned at 4 wks old, and reared within deep-bedded outdoor hoop houses. To compare pork characteristics, 104 randomly selected animals were harvested at a USDA-inspected abattoir at approximately 200 d of age. Variables measured included pH, color score, L*, a*, b*, marbling score, drip loss, hot carcass weight, backfat thickness (BF), loin muscle area (LMA), and slice shear force. Sensory panel tests were also conducted at two time periods. The data was analyzed with GLM in SAS 9.01 including location, trial, and sire breed as fixed effects. Backfat thickness, LMA, color score and a* were different among breeding groups (p<0.05). The LBY pigs had thicker backfat and smaller LMA than the other breed types. The TY and YY had less backfat than all other breed groups. Color score was lower for YY than BY and LBY but intermediate for TY. The a* was lower for TY than other breeds except LBY which was intermediate. For one sensory panel test, YY pork was more preferred overall as well as for juiciness and texture compared to BY and LBY (p<0.05), but no impact of breed type was noted for the other test, with values similar for BY, LBY, TY and YY pork. This information may help small farmers make decisions about breed types to use for outdoor production.

Effects of fermented oyster mushroom ( Pleurotus ostreats) by-product supplementation on growth performance, blood parameters and meat quality in finishing Berkshire pigs

The objective of the present study was to investigate the effects of fermented oyster mushroom (Pleurotus ostreats) by-production (FOMP) supplementation on the growth performance, blood parameters, carcass traits and meat quality in finishing Berkshire pigs. FOMP was made by mixing oyster mushroom by-production with rice bran and barley bran and this mixture was fermented for 60 days. The experimental diets were 0, 3, 5 and 7% of FOMP added to C, T1, T2 and T3 in the basis diet for 7 weeks. Average daily gain (kg/day) was higher in C and T1 than in T2 and T3 ( P < 0.05). Average daily feed intake (kg/day) and feed conversion increased by the addition of FOMP ( P < 0.05). Total cholesterol and high-density lipoprotein cholesterol were higher in T3 than other treatments ( P < 0.05). Carcass weight (kg) was higher in C and T1 than in T2 and T3 ( P < 0.05). Dressing (%) was higher in C than in T3 ( P < 0.05). Crude protein was lower in T3 than in other treatments ( P < 0.05). Crude fat was higher in T2 and T3 than in C ( P < 0.05). pH24 was higher in C than in other treatments ( P < 0.05). Cooking loss (%) was higher in T1 than T2 ( P < 0.05). Water-holding capacity (%) was higher in C than in T1 ( P < 0.05). In meat colour, CIE a* was lower by the addition of FOMP ( P < 0.05). CIE b* was higher in C than in other treatments ( P < 0.05). In backfat colour, CIE L* was lower in T3 than other treatments ( P < 0.05). CIE b* was lower by addition of FOMP ( P < 0.05). Palmitoleic and oleic acid were higher in T3 than in other treatments ( P < 0.05). Linoleic and arachidonic acids were higher in T2 than in other treatments ( P < 0.05). The results indicate that 3% of FOMP affected the growth performance, carcass traits, meat quality and fatty acid in contrast to addition of 5% of FOMP for Berkshire pigs during the finishing period.

Comparison of Growth Performance of Antibiotic-free Yorkshire Crossbreds Sired by Berkshire, Large Black, and Tamworth Breeds Raised in Hoop Structures

The objective of this study was to compare body weight, ADG, and feed:gain ratio of antibiotic-free pigs from Yorkshire dams and sired by Yorkshire (YY), Berkshire (BY), Large Black (LBY) or Tamworth (TY) boars. All the crossbred pigs in each of three trials were raised as one group from weaning to finishing in the same deep-bedded hoop, providing a comfortable environment for the animals which allowed rooting and other natural behaviors. Birth, weaning and litter weights were measured and recorded. From approximately 50 kg to market weight (125 kg), feed intake and body weights were recorded manually (body weight) or using a FIRE (Feed Intake Recording Equipment, Osborne Industries Inc. Osborne, Kansas) system with eight individual feeding stations. Feed intake data for 106 finishing pigs between 140 and 210 d of age and the resulting weights and feed conversion ratios were analyzed by breed type. Least square means for body weights (birth, weaning and to 240 d) were estimated with Proc Mixed in SAS 9.2 for fixed effects such as crossbreed and days of age within the sire breed. The differences within fixed effects were compared using least significant differences with DIFF option. Individual birth weights and weaning weights were influenced by sire breed (p<0.05). For birth weight, BY pigs were the lightest, TY and YY pigs were the heaviest but similar to each other and LBY pigs were intermediate. For weaning weights, BY and LBY pigs were heavier than TY and YY pigs. However, litter birth and weaning weights were not influenced by sire breed, and average daily gain was also not significantly different among breed types. Tamworth sired pigs had lower overall body weight gain, and feed conversion was lower in TY and YY groups than BY and LBY groups (p<0.05), however, number of observations was somewhat limited for feed conversion and for Tamworth pigs. Overall, no convincing differences among breed types were noted for this study, but growth performance in the outdoor environment was satisfactory.

Analyses of porcine public SNPs in coding-gene regions by re-sequencing and phenotypic association studies

The Porcine SNP database has a huge number of SNPs, but these SNPs are mostly found by computer data-mining procedures and have not been well characterized. We re-sequenced 1,439 porcine public SNPs from four commercial pig breeds and one Korean domestic breed (Korean Native pig, KNP) by using two DNA pools from eight unrelated animals in each breed. These SNPs were from 419 protein-coding genes covering the 18 autosomes, and the re-sequencing in breeds confirmed 690 public SNPs (47.9%) and 226 novel mutations (173 SNPs and 53 insertions/deletions). Thus, totally, 916 variations were found from our study. Of the 916 variations, 148 SNPs (16.2%) were found across all the five breeds, and 199 SNPs (21.7%) were breed specific polymorphisms. According to the SNP locations in the gene sequences, these 916 variations were categorized into 802 non-coding SNPs (785 in intron, 17 in 3'-UTR) and 114 coding SNPs (86 synonymous SNPs, 28 non-synonymous SNPs). The nucleotide substitution analyses for these SNPs revealed that 70.2% were from transitions, 20.0% from transversions, and the remaining 5.79% were deletions or insertions. Subsequently, we genotyped 261 SNPs from 180 genes in an experimental KNP × Landrace F2 cross by the Sequenom MassARRAY system. A total of 33 traits including growth, carcass composition and meat quality were analyzed for the phenotypic association tests using the 132 SNPs in 108 genes with minor allele frequency (MAF)>0.2. The association results showed that five marker-trait combinations were significant at the 5% experiment-wise level (ADCK4 for rear leg, MYH3 for rear leg, Hunter B, Loin weight and Shearforce) and four at the 10% experiment-wise level (DHX38 for average daily gain at live weight, LGALS9 for crude lipid, NGEF for front leg and LIFR for pH at 24 h). In addition, 49 SNPs in 44 genes showing significant association with the traits were detected at the 1% comparison-wise level. A large number of genes that function as enzymes, transcription factors or signalling molecules were considered as genetic markers for pig growth (RNF103, TSPAN31, DHX38, ABCF1, ABCC10, SCD5, KIAA0999 and FKBP10), muscling (HSPA5, PTPRM, NUP88, ADCK4, PLOD1, DLX1 and GRM8), fatness (PTGIS, IDH3B, RYR2 and NOL4) and meat quality traits (DUSP4, LIFR, NGEF, EWSR1, ACTN2, PLXND1, DLX3, LGALS9, ENO3, EPRS, TRIM29, EHMT2, RBM42, SESN2 and RAB4B). The SNPs or genes reported here may be beneficial to future marker assisted selection breeding in pigs.

Correlations of trained panel sensory values of cooked pork with fatty acid composition, muscle fiber type, and pork quality characteristics in Berkshire pigs

The objective was to examine the relationship of trained panel sensory scores of cooked pork with fatty acid composition, muscle fiber type, and meat quality characteristics from Berkshire pigs. No or few associations were found between the panel sensory scores of cooked meat, especially tenderness attributes, and fatty acid composition; however, intramuscular fat content positively correlated with off-flavor score (r=0.31). On the other hand, the morphological characteristics of muscle fibers were correlated with panel sensory values. Muscles with smaller cross-sectional area and higher density of fibers were more closely associated with softer, more tender panel scores and a lower number of chews than muscles with larger fiber area and lower density of fibers. The water holding capacity test of filter-paper fluid uptake was moderately correlated with panel scores of softness (r=0.33), initial tenderness (r=0.38), chewiness (r=0.40), juiciness (r=-0.27), flavor intensity (r=-0.23), and off-flavor (r=0.30). Panel sensory values of Berkshire pig meat was moderately related to postmortem meat quality, especially water holding capacity. A more thorough understanding of the relationships between fatty acid composition and muscle fiber type with palatability is needed.

The influence of giant fibres on utility for production of massaged products of porcine muscle longissimus dorsi

Musculus longissimus dorsi (L) originating from 6 genotype groups of pigs was examined. Three among these were parental lines: Pietrain (Pi), Duroc (D), Polish Large White x Polish Landrace (PLW x PL), the other three crossbreeds obtained by crossing the aforementioned parental lines: (PLW x PL) x Pi, (PLW x PL) x (PixD) and (PLW x PL) x (D x Pi). It was found that there exists a variety of numbers and sizes of giant fibres and sizes of muscle fibres in the L muscle of the groups of animals, which results in a diversity of quality and susceptibility to massaging. The largest number of giant fibres and the greatest sizes of normal and giant fibres, along with the largest losses after heat treatment, the highest hardness, shear force, the lowest juiciness and attractiveness were found in the L muscle of Pi. Muscle of this breed was characterised by the least change in quality indicators during massaging. The decrease of Pi breed genes in the crossbreed genotype, resulted in reduction in the quantity of giant fibres and fibre sizes in comparison with pure Pi breed, which increased quality of crossbreeds' muscles and their susceptibility to massaging.

Investigation of porcine FABP3 and LEPR gene polymorphisms and mRNA expression for variation in intramuscular fat content

Porcine chromosome 6 (SSC6) has been reported to have QTL affecting intramuscular fat content (IMF) in multiple populations. The objective of this study was to investigate the effect of FABP3 and LEPR genetic variations as well as their mRNA expression on the IMF trait in a three-generation of Korean native pig and Yorkshire crossed animals. Several polymorphisms of the FABP3 (HinfI, HaeIII and HinfI*) were significantly associated with moisture, tenderness and flavor score (P < 0.05), and were used to construct haplotypes: haplotype 1 (-TCT-) increased the marbling and intramuscular fat content, however, haplotype 2 (-CCT-) decreased tenderness. The LEPR AvaII polymorphism showed significant association with moisture, intramuscular fat, cholesterol and flavor score (P < 0.05). The linkage analyses with six microsatellites mapped FABP3 gene in the interval between the markers Sw1129 and S0228 (Sw1129--11.7 cM--FABP3-9.1 cM--S0228), and the LEPR gene between the markers S0121 and Sw322 (S0121--7.5 cM--LEPR--28.5 cM--Sw322). QTL mapping suggested a significant QTL affecting Moisture (83 cM) and IMF (84 cM) located close to marker S0228. The gene expression results showed that in the loin muscle, both of the FABP3 and LEPR genes showed significantly higher expression in pigs with higher IMF%, however, in the backfat, only FABP3 showed differential expression between these two groups of pigs (significantly higher expression in pigs with lower IMF%) (P < 0.05). In the liver, both of these two genes did not show any difference between the high and low IMF% groups.

Genetic parameters for preweaning and early growth traits in Berkshire pigs when creep feeding is used

The objective of this study was to find optimal traits for inclusion in selection criteria by estimating genetic parameters for direct genetic, maternal genetic, and common environmental effects for growth traits before 60 d of age and for the number of teats under an open breeding population, and to evaluate genetic relationships for traits at 60 d of age. Records of 2,344 male and 2,204 female purebred Berkshire pigs were analyzed. For BW at 14 d of age and for weaning weight, the heritabilities of a direct genetic effect were greater than those of a maternal genetic effect. This result is contrary to previous results showing a gradual decrease in the maternal genetic effect and an increase in the direct genetic effect up to weaning. The positive genetic correlations between direct and maternal genetic effects for BW at 14 d of age and weaning weight are clearly contrary to other reports. This phenomenon seems to be caused by creep feeding begun just after the birth of the piglets and maintained throughout the preweaning period in this Berkshire population.

Influence of early postweaning traits on genetic improvement of meat productivity in purebred Berkshire pigs

The objective of this study was to estimate genetic parameters for growth and body composition traits at 60 d of age and at finish in a population of Berkshire pigs and to evaluate the effectiveness of selection at 60 d of age for meat productivity. A total of 4,548 purebred Berkshire (2,344 males and 2,204 females) pigs born between December 1994 and January 2005 were used in this study. The traits analyzed were BW at 60 d of age; daily BW gain from birth to finish, from weaning to 60 d, from weaning to finish, and from 60 d to finish; age at finish; backfat thickness at 60 d of age and at finish; loin eye area at 60 d of age (LEA60) and at finish; and the number of teats. The heritability estimates for BW at 60 d of age, daily BW gain from weaning to 60 d, backfat thickness at 60 d of age, and LEA60 were 0.22, 0.25, 0.49, and 0.22, respectively. The estimated common environmental effect for BW at 60 d of age, daily BW gain from weaning to 60 d, backfat thickness at 60 d of age, and LEA60 were 0.12, 0.13, 0.18, and 0.21, respectively. Therefore, the common environmental effect should be included in the model to analyze traits at 60 d of age. The positive genetic correlation between LEA60 and loin eye area at finish and the negative genetic correlation between LEA60 and backfat thickness at finish indicated that improvement of the ultrasonic loin eye area at 60 d of age may result in favorable correlated responses to the traits at finish, an increase in loin eye area, and a decrease in backfat thickness. In addition, genetic correlations of backfat thickness at 60 d of age with backfat thickness at finish and loin eye area at finish were found to be favorable, indicating that improvement of ultrasonic backfat thickness at 60 d of age may result in greater correlated responses to the traits at finish: an increase in loin eye area and a decrease in backfat thickness. Therefore, constructing a selection scheme that includes body composition traits at 60 d and traits at finish is practical for gaining a greater selection response.

A combination of octanoate and oleate promotes in vitro differentiation of porcine intramuscular adipocytes

To understand the relationship between intramuscular adipogenesis in the pig and the supply fatty acids, we established a clonal porcine intramuscular preadipocyte (PIP) line from the marbling muscle tissue of female Duroc pig. Confluent PIP cells exhibited a fibroblastic appearance. Their adipogenic ability was investigated using confluent PIP cells after exchanging growth medium for adipogenic medium containing 50 ng/mL insulin, 0.25 microM dexamethasone, 2 mM octanoate, and 200 microM oleate. Appropriate concentrations of octanoate and oleate for the induction of adipogenesis were determined from the ability of cells to accumulate lipid and the toxicity of fatty acids. When cells were cultured in differentiation medium for 8 days, large numbers of lipid droplets were observed in differentiated PIP cells, and their cytosolic TG content increased in a time-dependent manner. While oleate only induced the expression of PPARgamma mRNA, but not that of C/EBPalpha, octanoate significantly induced the expression of both PPARgamma and C/EBPalpha mRNA. Octanoate and oleate accelerated the inducing effect of insulin and dexamethasone on the expression of aP2 mRNA. These results indicate that a combination of octanoate and oleate synergistically induced PIP adipogenesis, and that the stimulation of octanoate was essential to the trigger for the adipogenesis in PIP cells.

Effects of breed, sex, and halothane genotype on fatty acid composition of pork longissimus muscle1

The objective of this study was to estimate the effects of breed, sex, and halothane genotype on fatty acid composition and several fatty acid indices of lipid extracted from porcine LM. Purebred Yorkshire (n = 436), Duroc (n = 353), Hampshire (n = 218), Spotted (n = 187), Chester White (n = 173), Poland China (n = 124), Berkshire (n = 256), and Landrace (n = 187) pigs (n = 1,934; 1,128 barrows and 806 gilts) from 1991, 1992, 1994, and 2001 National Barrow Show Sire Progeny Tests were used. Pigs were classified as the HAL-1843 normal (NN) genotype (n = 1,718) or the HAL-1843 carrier (Nn) genotype (n = 216). For statistical analysis, a mixed model was used that included fixed effects of breed, sex, halothane genotype, test, slaughter date, interaction of breed x sex, and random effects of sire and dam within breed. Breed significantly affected the concentration of individual fatty acids, total lipid content, and the values of several fatty acid indices of LM. Duroc pigs had the greatest (P < 0.01) content of total SFA. Total MUFA concentration in Poland China pigs was greater (P < 0.05) than in all other breeds except the Spotted (P > 0.05). The concentrations of total PUFA were greater (P < 0.01) in Hampshire, Landrace, and Yorkshire pigs compared with those of other breeds. Significant sex differences for individual fatty acids were detected. Compared with gilts, barrows had greater (P < 0.01) concentrations of SFA and MUFA but lower (P < 0.01) total PUFA. Halothane genotype was a significant source of variation for the percentages of some fatty acids. Pigs with the carrier (Nn) genotype had lower concentrations of SFA (P < 0.05) and MUFA (P < 0.01) but a greater concentration of PUFA (P < 0.01) compared with NN pigs. There were significant negative correlations between total lipid content and individual PUFA and significant positive correlations between lipid concentration and most individual SFA and MUFA. In conclusion, the results suggest that breed and sex are important sources of variation for fatty acid composition of LM.

Carcass composition and meat quality of three different Iberian×Duroc genotype pigs

Carcass composition and meat quality of Longissimus dorsi (LD) and Biceps femoris (BF) muscles from three different Iberian×Duroc genotype pigs were studied: GEN1: ♂ Iberian×♀ Duroc1; GEN2: ♂ Duroc1×♀ Iberian; GEN3: ♂ Duroc2×♀ Iberian. Duroc1 (DU1) were selected for the manufacture of dry-cured meat products while Duroc2 (DU2) were pigs selected for meat production, with high percentages of meat cuts and low carcass fat. Genotype had a significant effect on the differences found while sex had not. GEN2 showed the highest weights at days 180 and 238 of weaning and the highest slaughter weights (day 316) followed by GEN3, while the lowest weights were found in GEN1. GEN3 had well conformed carcasses in comparison with GEN1 and GEN2, since GEN3 showed the highest percentages of ham and loin and the highest weight of loin as well as the lowest back and ham fat thickness. However, the use of DU2 pigs in the cross with Iberian had negative effects on meat quality, as GEN3 gave the worst meat quality in both muscles, postmortem pH, cook and drip loss, and colour and the lowest percentages of intramuscular fat (IMF). In subcutaneous fat (SCF), GEN3 had higher percentages of polyunsaturated fatty acids (PUFA) than GEN2, while GEN2 had higher saturated fatty acids (SFA) levels. In LD, IMF from GEN3 showed the highest percentage of MUFA and PUFA; while the fatty acid profile of GEN2 was more saturated. BF muscle showed similar trends, but not significantly so. On the other hand, few differences were found between reciprocal crosses (GEN1 vs. GEN2). GEN2 showed higher IMF in LD than GEN1, agreeing with their carcass weight. As a result, GEN1 had a fatty acid profile of IMF in the LD that was more unsaturated.

Quantitative trait loci mapping for fatty acid composition traits in perirenal and back fat using a Japanese wild boar x Large White intercross

Here, we analysed quantitative trait loci (QTL) for fatty acid composition, one of the factors affecting fat quality, in a Japanese wild boar x Large White cross. We found 25 significant effects for 17 traits at 13 positions at the 5% genome-wise level, of which 16 effects for 12 traits at 10 positions were significant at the 1% level. QTL for saturated fatty acids (SFA) in back fat were mapped to swine (Sus scrofa) chromosomes (SSC) 1p, 9 and 15. QTL for unsaturated fatty acids in back fat were mapped to SSC1p, 1q, 4, 5, 9, 15 and 17. Using a regression model that fits back fat thickness as a covariate, two of the QTL for linoleic acid content on SSC4 and SSC17 were not significant, but one QTL for total SFA composition was detected on SSC5 with correction for back fat thickness. Wild boar alleles at six of seven QTL tended to increase SFAs and to decrease unsaturated fatty acids. QTL for fatty acid composition in perirenal fat were mapped on SSC2, 3, 4, 5, 6, 14, 16 and X. QTL for melting point (in back fat samples) were mapped on SSC1, 2 and 15. Wild boar alleles in QTL on SSC1 and SSC15 were associated with elevated melting points whereas those on SSC2 were associated with lower melting point measurements.

Genetic correlations among fatty acid compositions in different sites of fat tissues, meat production, and meat quality traits in Duroc pigs

This study estimated genetic parameters for fatty acids of different sites of fat tissue, meat production, and meat quality traits of Duroc pigs selected during 7 generations for ADG, LM area, backfat thickness (BF), and intramuscular fat (IMF). For this study, 394 barrows and 153 gilts were slaughtered at 105 kg of BW. High heritabilities for C18:0 of outer and inner subcutaneous fat tissue were estimated, respectively, as 0.54 and 0.51; those of intermuscular and intramuscular fat were 0.40 and 0.51, respectively. Genetic and phenotypic correlations of ADG and BF with saturated fatty acids of outer and inner subcutaneous fat were positive, but those with C16:1 and C18:2 were negative, and those with C18:1 were nearly zero. Genetic and phenotypic correlations between LM area and respective fatty acids showed opposite results. Respective genetic and phenotypic correlations of melting points with C18:0 and C18:1 were positive and high, and negative and high, respectively. Genetic correlations between cooking loss and SFA (C14:0, C16:0, and C18:0) of IMF were positive and moderate: 0.56, 0.47, and 0.47, respectively. On the other hand, monosaturated fatty acid of C18:1 was highly and negatively correlated with cooking loss (-0.61). Moreover, high genetic correlation between meat color (pork color standard and lightness) and fatty acid compositions of IMF suggest that the SFA (C14:0, C16:0, and C18:0) were correlated genetically with meat lightness and that unsaturated fatty acid compositions (C18:1 and C18:2) were correlated with meat darkness. Results of this study suggest that the fatty acid composition of adipose tissue is correlated genetically with meat production and meat quality traits.