Duroc Genotypes Research Articles

Age Evolution of Lipid Accretion Rate in Boars Selected for Lean Meat and Duroc Barrows.

Simple SummaryFat deposition profile and fatty acid biosynthesis in adipose tissues are two relevant metabolic processes for breeding companies as the fat content of meat relates to its technological, organoleptic, and nutritional quality. Age, breed, and sex have a great impact on fat metabolism. Therefore, in the present experiment, a labeled saturated fatty acid was added to the diet of pigs belonging to three different producing types during two growth phases, to define the rate of its incorporation into body fat. In addition, the activity of the enzyme stearoyl-CoA desaturase, which promotes the conversion of some saturated fatty acids into monounsaturated, was analyzed. In the growing phase, direct incorporation of fat from diet was higher than biosynthesis in most adipose tissues, whereas in the fattening phase it was higher only in the liver, revealing the changing roles of organs in fat metabolism with age. The leaner pigs also obtained a higher fat incorporation, denoting higher reliance on dietary fatty acids for fat deposition; overall, real stearoyl-CoA desaturase activity was higher in the fattening phase.Fatty acid (FA) deposition in growing–fattening pigs is mainly based on endogenous lipid synthesis, but also direct FA incorporation from the diet. To evaluate the direct fat incorporation rates and the endogenous desaturation action of the stearoyl-CoA desaturase (SCD) enzyme, a deuterium (D)-labeled saturated FA (d35-C18:0) was added to the diet. Sixteen three-way (3W) crossbred boars, and thirty-two purebred Duroc barrows homozygous for the SCD single nucleotide polymorphism rs80912566 (16 CC/16 TT), were used. Half of the animals of each genotype belonged to the growing and fattening phases. The fractional incorporation rate (FIR) of dietary fat in growing pigs was generally higher in adipose tissues, whereas in fattening pigs it was higher in the liver. Duroc pigs exhibited lower FIRs than 3W pigs, suggesting lower rates of endogenous synthesis by 3W pigs. Real fractional unsaturation rates (FURs) increased with age by the higher FIRs in 3W pigs and the de novo synthesis pathway in Duroc genotypes. Moreover, pigs carrying the SCD_T allele showed more enhanced oleic acid biosynthesis than Duroc CC pigs. In conclusion, suitable feeding protocols should be designed for each pig type to optimize production traits, considering that the metabolic pathway of FA for its deposition may differ.

Meat quality in relation to swine well-being after transport and during lairage at the slaughterhouse

Cortisol and corticosterone in saliva were evaluated as pig stress biomarkers, using pig genotype (Duroc, L62 or Pietrain) and lairage time in the slaughterhouse (0, 2.0, 4.0 or 6.0 h) as controlled variables. Although some pigs were found to be carriers of stress susceptibility, all were healthy heterozygous individuals. Pre-slaughter transport increased cortisol levels in saliva above 3.0 μg/L (medium stress), and 4.0 h of lairage in the slaughterhouse raised them above 6.0 μg/L, whereas corticosterone concentrations exceeded 4 μg/L, which are suggestive of high stress. The highest cortisol levels were detected in the Duroc genotype. Other factors such as food deprivation, background noise, the presence of a large number of animals waiting to be slaughtered, mixing with unfamiliar animals or recent mixing of genders may also influence stress. Corticosterone proved a reliable indicator of high stress only. Meat quality from the pig breeds studied was not affected by lairage in the slaughterhouse for up to 6.0 h.

Survival Analysis of Hungarian Large White, Duroc and Pietrain Sows

The aim of the present study was to perform lifetime performance analysis in three pig breeds; Hungarian Large White (n=295), Duroc (n=76) and Pietrain (n=91) on a commercial farm using analysis of survival sows. We took into consideration the age of sows at the time of their inclusion into breeding, their age at the time of culling, time spent in production, number of mating and parities, parity percentage, intervals between litters, number and mean of piglets born alive and born dead, number of raised piglet litters, number and mean of 21 days old piglets, the weight and mean of raised litter and raise percentage.
 We carried out the analysis by SPSS 22.0. Single factor analysis of variants, Kaplan-Meier analysis and Cox PH model were used. The determination of the significance of risk rates differences was done by Wald chi square test.
 Our results showed that the average culling age were 1056 (±33.52) days for the Hungarian Large White, 735 (±73.56) days for Duroc and 818 (±71.98) days for the Pietrain.
 The log rank test of the survival analysis indicated a significant difference between the three tested genotypes (χ2=16.981, P<0.001), which means that the survival percentage of the individual breeds varied significantly from one another. In comparison with the Hungarian Large White genotype the Duroc genotype has a 1.6 times higher (P<0.001) culling risk while that of the genotype Pietrain was 1.36 times higher (P<0.001).
 Our results can be used to compare the breeds kept under the same conditions and to compare the life span of one genotype under different farming conditions. Factors that increase survival and improve the profitability of pig farming can be determined by this method.

Effect of selenium supplementation in pig feed on slaughter value and physicochemical and sensory characteristics of meat

AbstractThe aim of the study was to examine the assimilability of organic and inorganic selenium supplied as an additive to pig feed. The influence of both selenium forms on pig slaughter value as well as on the physicochemical and sensory characteristics of meat was also examined (experiment I). An attempt to establish the distribution of selenium in the body of experimental fatteners was made (experiment II). Experiment I was performed on 20 carcasses of crossbred pigs of (Polish Large White × Polish Landrace) × Duroc genotype and experiment II was carried out on 45 samples of longissimus and semimembranosus muscles taken from fatteners of the same genotype (PLW × PL × Duroc). The results obtained indicated that selenium supplementation in the diet had no impact on slaughter performance, meat quality and most physicochemical and sensory characteristics of meat. Selenium was found to have no significant effect on meat colour. The meat water holding capacity (WHC) was lower in the group of pigs fed organic selenium. The highest selenium concentration was found in the semimembranosus muscle of fatteners receiving the inorganic selenium additive.

Changes in Fatty Acid Composition of two Muscles from Three Different Iberian × Duroc Genotypes After Refrigerated Storage

The changes of the fatty acid (FA) profile of 2 muscles Longissimus dorsi and Biceps femoris from 3 Iberian × Duroc genotypes were studied: GEN1: ♂ Iberian × ♀ Duroc1, GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. GEN1 and GEN2 are reciprocal crosses while the difference between GEN2 and GEN3 is the Duroc sire line. The genotype Duroc1 was selected for the production of dry-cured meat products while the genotype Duroc2 was selected for meat production. Longissimus dorsi and Biceps femoris BF from the reciprocal cross showed similar changes in FAs profile after refrigerated storage. However, the Duroc sire line affected the FA profiles of intramuscular fat (IMF) and lipid fractions since some differences were found between GEN2 and GEN3. Meat from GEN3 had the highest level of polyunsaturated fatty acids (PUFA) in IMF and lipid fractions as well as the lowest rate of plasmalogens in polar lipid fraction. After storage, meat from GEN3 showed an increase of long chain PUFA in free fatty acids fraction and the highest increase in the ratio DMA/FA [(dimethylacetals/FAs) × 100] after the refrigerated storage, which was indicative of a higher deterioration of this genotype. Therefore, the crossbreeding of Iberian pigs with Duroc selected genotypes (Duroc2) could affect the changes in the FAs profile of meat under refrigerated storage.

Effect of Iberian × Duroc genotype on composition and sensory properties of dry‐cured ham

AbstractBACKGROUND: Dry‐cured ham quality from three different Iberian × Duroc genotypes was studied: GEN1, Iberian × Duroc1; GEN2, Duroc1 × Iberian; GEN3, Duroc2 × Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The line Duroc1 (DU1) was selected for the manufacture of dry‐cured meat products, whereas the line Duroc2 (DU2) was selected for meat production with low carcass fat.RESULTS: Dry‐cured hams from all genotypes had similar chemical composition. However, intramuscular fat of dry‐cured hams from GEN3 was more unsaturated than that from GEN2, while GEN1 was intermediate. Lipid oxidation, measured as 2‐thiobarbituric acid‐reactive substances (TBARS) and hexanal content, was similar between genotypes. The colour of hams was affected by genotype; hams from GEN2 showed higher lightness (CIE L*), while those from GEN3 had a less intense colour (lower a* and C*). Texture measured instrumentally did not differ between genotypes; however, in the sensory analysis, panellists considered hams from GEN3 more fibrous, while those from GEN2 were considered juicier. Hams from GEN3 were also perceived as saltier and more acid.CONCLUSION: Genotype affected the quality of Iberian hams, with those from GEN3 being of lower quality, and this genotype was considered less suitable for the manufacture of Iberian dry‐cured ham. Copyright © 2007 Society of Chemical Industry

Effect of Physico-chemical Characteristics of Raw Muscles from Three Iberian × Duroc Genotypes on Dry-cured Meat Products Quality

The effect of raw material characteristics (longissimus dorsi and biceps femoris) on dry-cured loin and ham quality from three different Iberian · Duroc genotypes was studied: GEN1: ♂ Iberian · ♀ Duroc1, GEN2: ♂ Duroc1 · ♀ Iberian; GEN3: ♂ Duroc2 · ♀ Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The line Duroc1 (DU1) was selected for the manufacture of dry-cured meat products, whereas the line Duroc2 (DU2) was selected for meat production with low carcass fat. Raw material and dry-cured meat products did not differ between reciprocal crosses (GEN1 vs. GEN2). However, the genotype of the Duroc sire line affected the quality of meat and dry-cured meat products. GEN1 and GEN2 had higher adipogenic nature and higher postmortem pH than GEN3, and as a result, these dry-cured meat products had better instrumental and sensory quality than those from GEN3. By contrast, meat from GEN3 had lower pH, fat content, and oxidative stability which decreased the quality of dry-cured meat products. Therefore, there was a close connection between raw material and dry-cured meat products quality as it was affected by characteristics related to the genotype such as the adipogenic character and meat quality traits associated with pH.

The crossbreeding of different Duroc lines with the Iberian pig affects colour and oxidative stability of meat during storage

Colour and oxidative stability of Longissimus dorsi (LD) and Biceps femoris (BF) muscles from 3 different Iberian × Duroc genotypes (GEN1: ♂ Iberian × ♀ Duroc1, GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian) were analysed during 10 days of refrigerated storage. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The genotype Duroc1 was selected for the manufacture of dry-cured-meat products while the genotype Duroc2 was selected for meat production. BF showed more intense colour and oxidative changes during storage than LD, which is in accordance with their different metabolic pattern, since BF is an intermediate oxidative muscle whereas LD is a glycolytic one. Important differences were found between crosses due to the genotype of the Duroc sire line; however, reciprocal crosses (GEN1 and GEN2) showed a similar pattern. The lowest post-mortem pH of GEN3 could be a deciding factor of the oxidative and colour stability during storage as GEN3 had higher drip and cook loss as well as higher susceptibility to iron-ascorbate-induced oxidation. In addition, chops from GEN3 were paler (lower L ∗) and showed a higher discolouration (higher decrease of a ∗) besides higher lipid (TBA-RS) and protein oxidation (carbonyl content) after the storage.

Volatile Profiles of Dry-Cured Meat Products from Three Different Iberian X Duroc Genotypes

Volatile profiles of two Iberian dry-cured products, dry-cured loin and ham, from three different Iberian x Duroc genotypes, was assessed. Three groups of 10 pigs, each (5 males and 5 females) from different genotypes, were studied: GEN1 = male Iberian x female Duroc1; GEN2 = male Duroc1 x female Iberian; and GEN3 = male Duroc2 x female Iberian. The genotype Duroc1 (DU1) corresponded to pigs selected for the production of dry-cured meat products (hams, loins, and shoulders), with a high level of fattening, while the genotype Duroc2 (DU2) corresponded to animals selected for meat production. Genotype slightly affected the volatile profiles of both dry-cured meat products, although dry-cured loin from GEN3 showed higher hexanal content. Dry-cured loin showed a volatile profile very different to that found in dry-cured ham. Volatile compounds of dry-cured meat products were mainly originated by lipid and protein degradation. Most of the volatile detected in both meat products came from lipid oxidation such as acids, aldehydes, ketones, alcohols, and hydrocarbons. In addition, a high proportion of volatile compounds from the Maillard reaction was found. Branched aldehydes and some sulfur and nitrogen compounds have their origin in the amino acids degradation by the Strecker reaction, while branched alcohols and acids come from the lipid oxidation of branched aldehydes. Dry-cured ham showed a higher number and a higher level of compounds with origin in protein and lipid degradation than dry-cured loin, which agrees with the longer ripening of the hams (24 months) with respect to the loins (4 months). In dry-cured loins, apart from these compounds, seasoning mixture provides high amount of volatiles, such as terpenes (from paprika and oregano) and sulfur compounds (from garlic), which have great importance in the overall aroma of this product.

Effect of Iberian × Duroc genotype on dry-cured loin quality

Dry-cured loins from three different pig genotypes were studied: GEN1: ♂ Iberian × ♀ Duroc1, GEN2: ♂ Duroc1 × ♀ Iberian; GEN3: ♂ Duroc2 × ♀ Iberian. GEN1 and GEN2 are reciprocal crosses, while the difference between GEN2 and GEN3 is the Duroc sire line. The genotype of pigs Duroc1 was selected for the manufacture of dry-cured meat products, while the genotype Duroc2 was selected for meat production. The chemical composition of the dry-cured loins was significantly different, especially the intramuscular fat (IMF) content which was highest in GEN2. Dry-cured loins from GEN3 showed lower CIE a ∗ and chroma values. IMF from GEN2 was more saturated whereas GEN3 had higher percentages of PUFA and MUFA. Loins from GEN3 had higher TBA-RS values ( p > 0.05) and hexanal contents. Loins from GEN3 had higher Warner–Bratzler shear force ( p > 0.05) and instrumental hardness than those from GEN2, being intermediate in GEN1. Panellists considered that loins from GEN2 were more marbled, more odorous, juicier, sweeter and less salty than loins from GEN3. Therefore, loins from GEN2 had the best quality, followed by GEN1, while GEN3 had the worst quality.

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.

Comparative Study of the Lifetime Productivity and Performance Characteristics of Meishan and Duroc Cross-bred Pigs

The objective of this study was to examine the potential of Meishan genotypes to improve production efficiency through increased reproductive performance and sow longevity. Sows of White composite, with either 1/4 Meishan, 1/4 Duroc or 1/8 Duroc were kept for up to six parities and reproductive performance and lifetime productivity of each sow breed was recorded. Progeny from these sows were analysed for growth and carcass characteristics. It was noted that Meishan genotype sows were more prolific (+1 pig/litter -1 ; P <0.05) and had greater longevity in the herd than either of the Duroc genotypes. The growth rate of slaughter pigs from 1/4 Meishan sows was slower than that of either 1/8 or 1/4 Duroc (893, 976 and 931 g day -1 , respectively; P <0.05) and they had poorer carcass lean content (56, 59 and 58%, respectively; P <0.05). The study would suggest that 1/4 Meishan sows may be useful for systems with low costs of production, small penalties for fat carcasses and where gilt replacement costs are high.

The influence of the proportion of Duroc genes on growth, carcass and pork eating quality characteristics

AbstractA study was carried out involving 721 pigs, comprising boars and gilts, with either 0, 0.25 , or 0.50 Duroc inclusion level, which were produced by mating Large White boars with Large White × British Landrace sows, Large White boars with Duroc × (Large White × British Landrace) sows, or Duroc boars with Large White × British Landrace sows, respectively. Animals were reared on one of seven different feeding regimens from 30 to 90 kg live weight. Tissue growth rates were determined using a triple sampling procedure based on a combination of full-side and ham joint dissection on subsamples of pigs (127 and 366 pigs, respectively) and P2 backfat thickness on the remainder. Initial body composition was determined at 30 kg on subsamples of the three genotypes. Daily food intakes increased with increasing Duroc inclusion but live-weight gains were similar for the three genotypes. Lean and fat growth rates and food conversion ratios were greatest for the 0·50 Duroc group, although the genotype differences were small. Killing-out proportions and P2 fat depths were higher for the 0.25 and 0·50 Duroc groups. The proportion of lean in the carcass was lower (P &lt; 0·01) for 0·50 Duroc pigs. Japanese colour scores and EEL reflectance indicated that the longissimus muscle was darker for the 0·25 and 0·50 Duroc genotypes. Subcutaneous fat firmness scores and penetrometer readings taken in the mid back indicated softer fat for the 0 Duroc group. Intramuscular fat levels increased (P &lt; 0·01) with increasing Duroc inclusion (10.4, 11.2, and 18·2 g/kg for the 0, 0.25, and 0.50 groups respectively). Cooked longissimus from pigs with 0·50 Duroc had a lower shear force and was judged to have a stronger pork odour and to be more tender and acceptable than that from the 0 Duroc group. The 0.25 Duroc group showed a small improvement in tenderness but a weaker pork odour and similar overall acceptability compared with the 0 Duroc group. This study suggests that the use of the Duroc in crossing systems in the United Kingdom will have limited impact on growth performance but that 0·50 Duroc inclusion will result in fatter carcasses, higher intramuscular fat levels and improved eating quality.