Long‐term effects on the digestive tract of feeding large amounts of resistant starch: A study in pigs

The present study aimed to assess the digestive consequences of the long‐term intake of two starches providing different amounts of resistant starch. Growing pigs were used as the animal model and meal‐fed for 14 weeks on a diet containing a high amount of either raw potato starch (RPS) or corn starch (CS). Digestive adaptation was chronologically evaluated by measuring organic matter (OM), crude protein (CP), neutral detergent fibre (NDF) and starch digestibility. After 97 days, whole‐tract digestibility of OM, CP and NDF was lower for RPS‐ compared to CS‐fed pigs, whereas no differences were observed in faecal starch digestibility. In contrast, starch digestibility was reduced in the proximal compartments (ileum, caecum and proximal colon) of animals fed the RPS diet. The concentration of short‐chain fatty acids (SCFAs; P < 0.05), and purine bases (PBs; P < 0.01) was also higher in distal colon and rectum of animals fed the RPS diet. Changes in bacterial community structure (dendogram analyses) were seen in the rectum. Biodiversity tends to increase more in RPS compared to CS fed animals (34.1 vs. 28.8; P = 0.07). Among SCFAs, the proportion of butyrate was two‐fold higher in proximal colon digesta of RPS compared to CS fed pigs (0.20 vs. 0.11; P < 0.05). Increased butyrate formation in the colon reduced the number of apoptosis per crypt in the proximal colonic mucosa (0.38 vs. 0.62; P < 0.05). RPS fermentation reduced indices associated with damage to intestinal epithelial cells, such as crypt cell hyperproliferation and magnesium excretion. Long‐term ingestion of RPS induces pronounced changes of the digestive tract and their microflora, modifying mineral absorption and colonic morphology for which health benefits are likely to be associated. Copyright © 2007 Society of Chemical Industry     

Cholesterol Content and Fatty Acids Composition of Mangalitsa Pork Meat

The aim of this study was to examine variability in cholesterol content and fatty acid composition in musculuslongissimus (MLLT) of various genotypes of pigs. Out of 30 male castrated animals used in the trial, 20 were Mangalitsa pigs (Swallow Belly - SBM and White - WM) while 10 were of the Swedish Landrace breed – SL. The representative of pig meat breeds, SL had significantly less cholesterol in MLLT compared to SBM and WM pigs. The total monounsaturated fatty acids (MUFA) and unsaturated fatty acids (USFA) content was higher in SBM and WM than in SL pigs (p< 0.001).     

Comparing the histochemical characteristics and meat quality traits of different pig breeds

The purpose of this study was to compare the muscle histochemical characteristics and meat quality traits between Berkshire, Landrace, Yorkshire, and crossbred pigs. A total of 594 pigs were evaluated. A clear difference between histochemical properties was observed from the results for fiber type composition. In Berkshire pigs, the area percentage of type I fibers was higher (P < 0.001) and that of type IIb fibers was lower (P < 0.05) than those of other breeds. The muscle pH_45min and pH_24h were significantly higher in Berkshire pigs. Drip loss and color parameters were significantly different between the breeds (P < 0.001). The Berkshire pigs, which showed the highest muscle pH and lowest drip loss and L^* values, contained a significantly higher percentage of type I fibers than the other breeds. By comparing the fiber type compositions of the different breeds, the results imply that the longissimus dorsi muscle of Berkshire pigs is more oxidative than that of other breeds. A high pH value in Berkshire pigs is due to a high percentage of type I fibers and a low percentage of type IIb fibers. Based on these results, we conclude that muscle fiber composition can explain in parts the variation of meat quality across and within breeds.     

Effect of different condensed tannin‐containing forages,forage maturity and nitrogen fertiliser application on the formation of indole and skatole in in vitro rumen fermentations

The objectives of this work were to establish the effect of seven different forages with a varied condensed tannin (CT) content, plant maturity and nitrogen fertiliser application on the ruminal formation of skatole and indole using an in vitro method designed to mimic rumen fermentation conditions. After 10 h of incubation, the concentration of indole and skatole was highest when incubating white clover (P < 0.05). Polyethylene glycol addition, to inhibit CT, showed that CT significantly reduced the formation of indole and skatole when incubating Lotus corniculatus, sulla, Dorynium rectum and Lotus pedunculatus (P < 0.01). Mature forage growth resulted in a significantly lower concentration of indole and skatole being formed in vitro compared to the incubation of new spring growth (P < 0.001). A higher application of nitrogen fertiliser to perennial ryegrass‐based pasture resulted in a higher crude protein concentration in the plant and a significantly higher concentration of skatole formed in vitro (P < 0.001). Forages containing CT reduced the conversion of endogenous protein to indole and skatole and plants containing a higher CT concentration tended to be more effective, but compositional differences of CT between forages may also have had an influence. New forage growth or swards that had a high application of nitrogen fertiliser promoted the formation of indole and skatole. Copyright © 2007 Society of Chemical Industry     

Comparison of muscle proteome profiles in pure breeds of Norwegian Landrace and Duroc at three different ages

We have used proteomics as a tool to unravel the changes in protein composition between two pure pig breeds and three age groups. Forty two female pigs of Norwegian Landrace and Duroc breed slaughtered at 6, 9 and 12 months age were included in the study. Each of the breeds was raised in separate farms and was slaughtered at the same day in a commercial abattoir. A sample from the adductor muscle was collected approximately 45 min postmortem. Proteome analyses of the water soluble proteins using 2D electrophoresis showed that of the 1125 analyzed protein spots, 94 and 41 proteins are changed in abundance according to breed and age, respectively. A total of 63 changed proteins were identified by mass spectrometry. The identified proteins were classified as structural proteins, metabolic proteins, stress/defense proteins and other proteins. This demonstrates a difference in metabolism and muscle composition between breeds and age groups and shows that proteomics is a useful tool to uncover the molecular basis for physiological differences in muscles between pig breeds and age groups.     

Food intake and live growth performance of pigs measured automatically and continuously from 25 to 115 kg live weight

Continuous automatic measurement and electronic recording provided data for individual pig live weight and food intake on a daily basis for a total of 74 pigs representing three commercially available crossbred types of mixed genetic origin, which were kept under commercial farming conditions to determine practical expectations for food intake and performance characteristics over the whole of the growth range from 25 to 115 kg live weight. The pig types were named as ‘Landrace’ type, ‘Pietrain’ type and ‘Meishan’ type, having been chosen to represent ‘lean’, ‘meaty’ and ‘fatty’ types. The pigs were fed ad libitum and serially slaughtered in groups at 32, 42, 63, 82 and 112 kg live weight (W). Results are presented in the order of pig type as above. Daily live weight gains at 80 kg live weight were 0.93, 0.94 and 0.91 kg day^?1 and at 100 kg were 1.04, 0.81 and 0.75 kg day^?1. Food intake curves differed with respect to both position and shape, with ‘Pietrain’ type pigs showing a lower increase with increasing live weight. Significant differences were found in the levels of fatness, as measured by P2 backfat depth, of the three pig types across the weight range examined (P < 0.001), in order of fatness ‘Pietrain’ type < ‘Landrace’ type < ‘Meishan’ type. Copyright © 2003 Society of Chemical Industry     

不同品种猪肉鲜味特征比较研究

选择商品化猪场养殖的东北民猪、北京黑猪、五指山猪及杜长大外三元杂交猪作为研究对象,对其宰后背最长肌中肌苷酸、肌苷、次黄嘌呤、谷氨酸、天冬氨酸含量及味精当量的差异进行比较研究。结果表明:东北民猪背最长肌肌苷酸含量最高,显著高于杜长大外三元杂交猪、北京黑猪和五指山猪(P<0.05);东北民猪背最长肌次黄嘌呤与肌苷含量最低(P<0.01);北京黑猪背最长肌天冬氨酸含量显著高于其他品种(P<0.05),谷氨酸含量极显著高于东北民猪和五指山猪(P<0.01),五指山猪背最长肌谷氨酸与天冬氨酸含量均显著低于其他品种(P<0.05);东北民猪、北京黑猪和杜长大外三元杂交猪的味精当量极显著高于五指山猪(P<0.01)。     

The effect of age on distribution of skatole and indole levels in entire male pigs in four breeds: Yorkshire, Landrace, Hampshire and Duroc

High skatole and to a lesser degree indole levels in some entire male pigs result in occurrence of off-flavor in meat, called boar taint. In this study, plasma samples from 117 Yorkshire, 134 Landrace, 184 Hampshire and 75 Duroc entire male pigs collected at different ages were analyzed for skatole and slightly fewer samples for indole concentrations. For each breed, a distinct age-related distribution of plasma skatole levels was observed. Skatole levels were increased at approximately 180-200 days of age, reaching very high levels is some individuals. Afterwards, the levels decreased; in Yorkshire and Landrace at approximately 240-260 and in Hampshire and Duroc at 310-360 days of age. The decrease of skatole levels was also observed in samples collected from 15 Landrace boars at two different ages: 16.8 μg/L (SD=17.36) vs. 5.9 μg/L (SD=3.48, p=0.016) in samples taken at the mean age of 210 and 314 days, respectively. Indole levels showed similar age- and breed-related variations to skatole. At the time of increased skatole concentrations (age from 180 to 360 days, depending on breed) 25.5% of Yorkshire, 31.6% of Landrace, 20.3% of Hampshire and 61.1% of Duroc entire male pigs had skatole levels above 12.6 μg/L of plasma, which corresponds to the threshold level of 0.20 μg/g of fat that is used for selecting tainted carcasses. The results indicate that increased levels of skatole in entire male pigs are related to puberty and taking skatole measurements at that age could be advantageous when considering genetic selection to reduce boar taint level in entire male pigs. Breed differences should be also taken into account.     

The effect of supplementation of a white clover or perennial ryegrass diet with grape seed extract on indole and skatole metabolism and the sensory characteristics of lamb

Condensed tannin in the form of a grape seed extract (GSE) was dosed to weaned wether lambs fed white clover (WC) or perennial ryegrass (PRG) over a 9‐week period to determine whether the ‘pastoral’ flavour and odour of meat could be altered. The concentrations of the pastoral flavour compounds indole and skatole were determined in the rumen fluid, blood plasma and intermuscular fat. The odour and flavour of fat and meat from the slaughtered lambs was assessed by a trained panel. The rumen fluid and blood plasma concentrations of indole and skatole were higher in those lambs fed WC compared to PRG (P < 0.05) and the overall meat flavour intensity was greater when feeding WC (P < 0.01). The observed concentration of indole and skatole in the fat between WC and PRG feeding treatments was not statistically different. Power analysis indicated that increasing the number of lambs per treatment group from 20 to 65 would result in a higher fat skatole concentration (P < 0.05) being detected in lambs fed WC compared to PRG. Dosing with GSE gave a small reduction in skatole concentration in the rumen fluid and reduced plasma concentration of indole and skatole (P < 0.001). Odour and flavour scores of the fat and meat samples were not particularly high however, dosing with GSE lowered the overall and sweet odour and the sheepy, camphor, faecal and barnyard flavour (P < 0.05). Although the plasma concentration of indole and skatole suggests that GSE reduced indole and skatole formation, the intermittent supply of the GSE to the rumen environment was not sufficient to reduce their concentration in the fat. Hence, the small difference in the scores for pastoral odour and flavour attributes associated with GSE treatment may arise from other unknown factors. From a primary investigation, there was no difference in the concentration of indole and skatole in fat samples collected from carcasses before and after chilling. Further investigations into meat pastoral flavour are warranted through feeding condensed tannin‐containing forages. Copyright © 2007 Society of Chemical Industry     

Comparisons of longissimus muscle metabolic enzymes and muscle fiber types in Korean and western pig breeds

We compared differentially expressed genes and muscle fiber types in the longissimus muscles of Korean native pigs (KNP) and the western meat-producing breeds Landrace and Yorkshire. The KNP breed exhibited a higher muscle fat content and more red meat color as determined by the a^* (redness) value (P < 0.01) and b^* (yellowness) value (P < 0.05) compared to the western breeds. Using differential display RT-PCR, we detected two genes that were differentially expressed in skeletal muscle among the pig breeds. These genes were identified as NADH dehydrogenase subunit 1 and ATPase subunit 6 by cloning and sequencing analysis. Both of these genes are involved oxidative phosphorylation and therefore energy metabolism. The genes were more highly expressed in the KNP breed than in the other breeds, indicating that KNPs exhibit more oxidative metabolism than do the western breeds. We also analyzed the mRNA levels of myosin heavy-chain isoforms such as type I (oxidative), type IIb (glycolytic), and types IIa and IIx (intermediate) fibers using real-time RT-PCR. The mRNA levels of oxidative and intermediate fibers were elevated in the KNP breed, whereas the glycolytic fibers were more highly expressed in the Landrace and Yorkshire pigs. These results suggest that the elevated expression of the oxidation-related metabolism genes NADH dehydrogenase and ATPase is related to meat quality as indicated by a higher content of oxidative fibers and muscle fat, as well as redder meat color.     

Chemical composition and mineral content of goat milk from four indigenous Portuguese breeds in relation to one foreign breed

Raw goat milk samples from Saanen and indigenous Portuguese breeds were analysed for gross composition, minerals and trace elements. Mean results revealed that some distinction could be seen for the Serrana breed. A significant geographical difference (P < 0.05) between Serrana herds was also observed. Generally, milk from Saanen did not differ significantly (P > 0.05) from that of the indigenous Portuguese breeds. Multivariate analysis showed that goat breeds could be divided into two groups, the ones reared mainly inland and those reared towards the coast. Potentially toxic elements were not detected.     

Effect of different production typologies on chemical,physical and sensory characteristics of Italian commercial pork

BACKGROUND: Slaughter weight could influence some chemical, physical and sensory characteristics of pork production. The aim was to compare loin quality from pigs slaughtered at 120 kg or at 160 kg live weight, representing two different Italian lines of commercial production. RESULTS: Physical and chemical traits were affected by slaughter weight, but lower values of moisture (P < 0.01) and higher fat content (P < 0.05) were found in heavy pork loin; furthermore, increased slaughter weight resulted in redder, yellower and more intense colour (P < 0.05). Slaughter weight did not influence the purchase intent or consumer preference, except for fresh meat colour (P < 0.05) preferred in light pigs. A selected and trained panel carried out a difference‐from‐control test, showing that heavy pig loin was redder, more marbled, moister, sweeter, saltier, and had a more metallic flavour and lower tenderness than the light one (P < 0.05). The colour difference of raw meat is the only parameter detected by the consumers. CONCLUSION: Different production typologies affected chemical and physical characteristics of loin. Moreover sensory evaluation showed substantial differences between the loin samples. However, the purchase intent and consumer preference were not influenced by these two production typologies. Copyright © 2008 Society of Chemical Industry     

The relationship between the chemical composition of the carcass and the fatty acid composition of intramuscular fat and backfat of several pig breeds slaughtered at different weights

Pigs of Belgian Landrace (B), Duroc (D), Hampshire (H), and Pietrain (P) breeds were slaughtered at 90, 110 and 130 kg body weight (BW) and the carcass chemical composition and fatty acid profiles of intramuscular fat of loin and backfat were determined. The carcass of Pietrain pigs had a higher concentration of protein and less fat than of B, D and H breeds. In tissues, the PUFA:SFA ratio was lower in the heavier (130 kg BW) than in lighter pigs (90 and 110 kg BW). This feature was higher in P pigs compared with the other breeds. The backfat had a higher concentration of PUFA:SFA ratio than intramuscular fat. The PUFA n− 6:n− 3 ratio was not affected by the breed and weight of pigs, but it was lower in backfat than in longissimus muscle fat. The protein concentration in the carcass was positively related to PUFA and negatively to SFA concentration in tissues.     

Mitochondrial respiratory activity in porcine longissimus muscle fibers of different pig genetics in relation to their meat quality

The pig genetics of Duroc, Pietrain (MHS homozygote negative, PiNN), Pietrain (MHS homozygote positive, PiPP) and a F2-Duroc-Pietrain cross-breed were analyzed. The animals had comparable (P > 0.05) carcass weights, but the PiPP pigs had higher carcass yield and lean meat values (P < 0.05). Considering the meat quality characteristics, the PiPP showed a faster pH drop and higher electrical conductivity, drip loss, shear force as well as lightness and redness values (P < 0.05). The PiPP animals had less slow-twitch-oxidative (STO) and more fast-twitch-glycolytic (FTG) muscle fibers, whereas the results of the Duroc animals were converse (P < 0.05). The STO and FTG fibers of the PiPP animals were larger than those of the other genetics (P < 0.05). The analysis of the mitochondrial respiratory activity (MRA) using permeabilized longissimus muscle fibers resulted in no differences between the pig genetics before and immediately after slaughter. During chilling the MRA decreased in all pigs but to a higher extent in the PiPP pigs (P < 0.05).     

Nutritional value of feed grade chickpeas for ruminants and pigs

The feeding value of feed grade chickpeas (Kabuli and Desi type) for ruminants and pigs was determined in two studies. Two ruminally fistulated cows were used in the first study to determine the effects of moist heat treatment (127 °C for 10 min) on the ruminal protein degradability of feed grade chickpeas. Heat treatment reduced (P < 0.05) soluble crude protein and increased (P < 0.05) the amount of crude protein associated with neutral detergent fibre for both types of chickpeas. Ruminal degradability of crude protein for Kabuli and Desi chickpeas was reduced by 39 and 33% (P < 0.05) respectively as a result of heating. In the second study, 64 crossbred pigs were each assigned to one of four dietary treatments in a factorial (4 treatments × 2 sexes) design experiment. The experimental barley/wheat‐based diets were supplemented with either soybean meal (control), Kabuli chickpeas (300 g kg⁻¹), Desi chickpeas (300 g kg⁻¹) or field peas (300 g kg⁻¹). Dry matter and gross energy digestibility coefficients, determined using the indicator method, were lower (P < 0.05) for the Desi‐ than for the Kabuli‐supplemented diet. However, no differences were observed in dry matter or gross energy digestibility between the Kabuli chickpea‐supplemented diet and the control or the field pea‐supplemented diet. Diets supplemented with chickpeas or field peas had a lower (P < 0.05) crude protein digestibility than the control diet. Pigs fed either of the chickpea‐supplemented diets during the growing phase gained less (P < 0.05) than pigs fed the control diet. However, during the finishing phase and over the entire experiment, dietary treatment had no effect on pig performance. There were no significant differences in carcass traits between pigs fed any of the four diets. It was concluded that moist heat treatment is an effective method to increase the rumen escape protein value of chickpeas and that the inclusion of feed grade Kabuli or Desi chickpeas in finishing diets up 300 g kg⁻¹ had no detrimental effects on pig performance. © 2000 Society of Chemical Industry     

Enzyme deactivation treatments did not decrease the beneficial role of oat food in intestinal microbiota and short‐chain fatty acids: an in vivo study

BACKGROUND: Steaming and roasting treatments are widely used enzyme deactivation methods in the oat food industry in China. Whether or not the enzyme deactivation treatments affect the nutritional function of oat foods is unknown. In the current study, we examined the effects of 4‐week ingestion of steamed or roasted oat foods on the intestinal bacteria and short‐chain fatty acids of rats. RESULTS: Compared with rats taking no oat foods, rats taking normal oat foods or enzyme‐deactivated oat foods showed significantly higher (P < 0.05) counts of Lactobacillus spp. and Bifidobacterium spp. in colon, significantly lower (P < 0.05) counts of Enterococcus spp. and coliforms in colon, and significantly higher (P < 0.05) levels of butyrate and acetate in colonic digesta. In addition, rats taking infrared roasting (IR)‐treated oat foods also demonstrated significantly higher (P < 0.05) fecal Lactobacillus spp. counts and significantly lower (P < 0.05) cecal and fecal counts of E. coli, Enterococcus spp. and coliforms than rats taking no oat foods. As for the comparison between the enzyme‐undeactivated oat group and the three enzyme‐deactivated oat groups, there were no significant differences in most of the parameters (P > 0.05), though a few exceptions did exist. CONCLUSION: Enzyme deactivation treatments did not decrease the beneficial role of oat food in the intestinal microbes and short‐chain fatty acids of rats. © 2012 Society of Chemical Industry     

Comparison of muscle proteolytic and lipolytic enzyme levels in raw hams from Iberian and White pigs

Muscle enzyme activities in Biceps femoris from Iberian and White crossbreeds were quantified in vitro to determine possible differences due to crossbreed and the different slaughtering age (12-month-old Iberian pigs and 6-month-old White pigs). Large differences were found between proteolytic and lipolytic enzyme levels from the skeletal muscle of Iberian pig breed and White pig crossbreed. In raw hams from Iberian pig, calpain and cathepsin (B, L and H) were significantly lower, while cathepsin D was significantly higher than in White pigs. Significantly lower dipeptidyl peptidase (II and IV), aminopeptidase B, leucyl and pyroglutamyl aminopeptidase activities were found in Iberian pig breed compared with White pig crossbreed. Significantly higher levels of dipeptidyl peptidase III and alanyl aminopeptidase and lower activities of acid lipase and neutral esterase were found in Iberian breed. It was concluded that lower muscle enzyme activities and in consequence slower proteolysis and lipolysis should be desirable to obtain higher quality in dry-cured products. © 1998 SCI     

Effect of breed type,housing and feeding system on performance of growing pigs managed under organic conditions

BACKGROUND: There is a need for information on the performance and carcass quality of pigs under different organic management systems. This study compared Duroc‐sired progeny from three maternal breed types when kept either at pasture or in housing with an outdoor run and offered ad libitum concentrate either alone or with fodder beet or grass/clover silage as additional forage. RESULTS: Liveweight gain, feed intake and the proportion of forages consumed did not differ between genotypes. Carcass fatness of progeny was lowest for a ‘modern’ genotype (Camborough 12) and highest for a ‘traditional’ purebred genotype (Saddleback), with a ‘crossbred traditional’ genotype (Saddleback × Duroc) being intermediate (11.4, 14.3 and 13.4 mm P₂ respectively, standard error of mean (SEM) 0.27, P < 0.001). With a cereal‐based concentrate available ad libitum, intake of forages was low (<2% of dry matter intake). Although growth rate did not differ between housing systems, daily feed intake was greater at pasture (2.47 vs 2.22 kg meal equivalent, SEM 0.05, P < 0.001), giving poorer feed efficiency (P < 0.01). Pastured animals consumed less additional forage and had a higher killing‐out % but similar carcass fatness. CONCLUSION: For organic pig production to be financially sustainable, disadvantages arising from the genotype and/or rearing system chosen need to be offset by a market premium for the pigs produced. Copyright © 2007 Society of Chemical Industry     

Surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry: A tool to predict pork quality

Expression of water soluble proteins of fresh pork Longissimus thoracis from 4 pure breed pigs (Duroc, Large White, Landrace, and Piétrain) was studied to identify candidate protein markers for meat quality. Surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (SELDI-TOF-MS) was used to obtain the soluble protein profiles of Longissimus thoracis muscles. The pure breeds showed differences among the studied meat quality traits (pH_u, drip loss, androstenone, marbling, intramuscular fat, texture, and moisture), but no significant differences were detected in sensory analysis. Associations between protein peaks obtained with SELDI-TOF-MS and meat quality traits, mainly water holding capacity, texture and skatole were observed. Of these peaks, a total of 10 peaks from CM10 array and 6 peaks from Q10 array were candidate soluble protein markers for pork loin quality. The developed models explained a limited proportion of the variability, however they point out interesting relationships between protein expression and meat quality.     

Evaluation of barley and triticale as feed ingredients in growing Iberian pigs: amino acid and carbohydrate ileal digestibility

BACKGROUND: Iberian pig production is linked to the use of the Mediterranean woodland, where the use of local feed resources is of paramount importance for the sustainability of the system. The aim of the present work was to explore the potential of triticale cv. Camarma as compared to barley cv. Esgueva in Iberian pig feeding by studying their respective ileal digestibilities of amino acids and carbohydrates in animals cannulated at the end of the ileum. RESULTS: Leu, Met and Tyr had (P < 0.05) greater standardised ileal digestibilities (SID) in pigs fed triticale diet. There was a trend (P = 0.07) towards greater SID of Thr in pigs fed the barley diet. The least digestible indispensable amino acids were Ile (74.6% SID) for barley and Thr (78.9% SID) for triticale. Except for β‐glucans, apparent ileal digestibilities (AIDs) of individual non‐starch polysaccharide (NSP), sugars and starch were greater in pigs fed triticale (P < 0.05). Nevertheless, total amounts of NSP digested were greater in pigs fed the barley diet (P < 0.05). CONCLUSION: Overall, triticale cv. Camarma had greater amino acid and carbohydrate AID than barley cv. Esgueva and may represent a valuable grain for Iberian pig feeding. Copyright © 2008 Society of Chemical Industry