Effect of lipid supplements on ruminal biohydrogenation intermediates and muscle fatty acids in lambs

High-Energy Supplemental Feeding Shifts Gut Microbiota Composition and Function in Red Deer (Cervus elaphus)

Winter supplemental feeding (SF) is commonly used to improve the survival of captive wildlife. To investigate the impact of winter supplementation on the gut microbiota of wildlife, we assessed changes in the gut microbiota of red deer (Cervus elaphus) during the supplementary and non-supplementary feeding (NSF) groups using 16S rRNA sequencing technology. We found no significant differences in the diversity of the gut microbiota between SF and NSF except for the Simpson's index. However, the relative abundance of Bacteroidetes, Lentisphaerae, and Proteobacteria in the gut microbiota was significantly higher during SF. Further, genera such as Intestinimonas, Rikenella, Lawsonibacter, Muribaculum, and Papillibacter were more abundant during SF. Beta diversity analysis showed significant differences between SF and NSF. The microbes detected during SF were primarily associated with lipid metabolism, whereas those detected during NSF were linked to fiber catabolism. High-energy feed affects the gut microbial composition and function in red deer. During SF, the gut microbes in red deer were enriched in microorganisms associated with butyrate and lipid metabolism, such as R. microfusus, M. intestinale, and Papillibacter cinnamivorans. These gut microbes may be involved in ameliorating obesity associated with high-energy diets. In summary, SF is a reasonable and effective management strategy.

Dietary combination of linseed and hazelnut skin as a sustainable strategy to enrich lamb with health promoting fatty acids

This study investigated the effect of the inclusion of extruded linseed and hazelnut skin on fatty acid (FA) metabolism in finishing lambs. Forty lambs were divided into 4 groups and fed for 60 d with: a conventional cereal-based diet, or the same diet with 8% of extruded linseed, or 15% of hazelnut skin, or 4% of linseed plus 7.5% of hazelnut skin as partial replacement of maize. Dietary treatments did not affect growth performances, carcass traits, and ruminal fermentation. The combined effect of linseed and hazelnut skin enriched the intramuscular fat with health promoting FA. Particularly, increases in α-linolenic acid (3.75-fold), and very long-chain n-3 poly-unsaturated FA (+ 40%) were attributed to the supplementation with linseed, rich in α-linolenic acid. In addition, increases in rumenic (+ 33%), and vaccenic (+ 59%) acids were attributed to hazelnut skin tannins modulating ruminal biohydrogenation and accumulating intermediate metabolites. The simultaneous inclusion of linseed and hazelnut skin can be a profitable strategy for enriching the intramuscular fat of lambs with health promoting FA, without adverse effects on ruminal fermentation and animal performance.

Comparison of the gut microbiota and metabolites between Diannan small ear pigs and Diqing Tibetan pigs

Objective

Host genetics and environment participate in the shaping of gut microbiota. Diannan small ear pigs and Diqing Tibetan pigs are excellent native pig breeds in China and live in different environments. However, the gut microbiota of Diannan small ear pigs and Diqing Tibetan pigs were still rarely understood. Therefore, this study aimed to analyze the composition characteristics of gut microbiota and metabolites in Diannan small ear pigs and Diqing Tibetan pigs.

Methods

Fresh feces of 6 pigs were randomly collected from 20 4-month-old Diannan small ear pigs (DA group) and 20 4-month-old Diqing Tibetan pigs (TA group) for high-throughput 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC-MS) non-targeted metabolome analysis.

Results

The results revealed that Firmicutes and Bacteroidetes were the dominant phyla in the two groups. Chao1 and ACE indices differed substantially between DA and TA groups. Compared with the DA group, the relative abundance of Prevotellaceae, and Ruminococcus was significantly enriched in the TA group, while the relative abundance of Lachnospiraceae, Actinomyces, and Butyricicoccus was significantly reduced. Cholecalciferol, 5-dehydroepisterol, stigmasterol, adrenic acid, and docosahexaenoic acid were significantly enriched in DA group, which was involved in the steroid biosynthesis and biosynthesis of unsaturated fatty acids. 3-phenylpropanoic acid, L-tyrosine, phedrine, rhizoctin B, and rhizoctin D were significantly enriched in TA group, which was involved in the phenylalanine metabolism and phosphonate and phosphinate metabolism.

Conclusion

We found that significant differences in gut microbiota composition and metabolite between Diannan small ear pigs and Diqing Tibetan pigs, which provide a theoretical basis for exploring the relationship between gut microbiota and pig breeds.

Effect of dietary pomegranate by-product on lamb flavour

This study evaluated the effect of the dietary inclusion of whole pomegranate by-product (WPB) on lamb flavour. Seventeen Comisana male lambs (body weight 14.82 kg ± 2 kg) were assigned to 2 treatments. During 36-day feeding trial, the control group (n = 8) received a conventional concentrate diet; the other group (n = 9) received a concentrate diet containing 200 g/kg (dry matter) of WPB, replacing part of barley and corn. After slaughter, fatty acids were determined in raw meat, while volatile organic compounds, SMart nose, and sensory traits were analysed in cooked meat. The concentrations of total polyunsaturated fatty acids, vaccenic and rumenic acid were higher in WPB meat. Most of volatile compounds that arise from lipid degradation (i.e., aldehydes, alcohols, ketones, and hydrocarbons) were found at higher concentrations in the WPB meat than in the control, except for 2-pentanone that was greater in control meat. Although SMart nose clearly discriminated between dietary treatments, consumer panel did not detect differences in meat flavour.

Enrichment of Dairy-Type Lamb Diet with Microencapsulated Omega-3 Fish Oil: Effects on Growth, Carcass Quality and Meat Fatty Acids

The hypothesis that adding omega-3 oil to feedlot pellets will improve the meat's favourable n-3 PUFA composition was tested in this experiment. Therefore, we evaluated the productive traits and modification of the composition of n-3 PUFA of Longissimus lumborum (LL) muscle in growing lambs supplemented with microencapsulated omega-3 oil (MEOIL) in pelleted total mixed rations (TMR). Thirty six one month old Valle del Belice male lambs (14.04 ± 0.1 kg) were randomly distributed to one of the three dietary treatments (n = 12 lambs each) and provided the supplemented diets up to 14 weeks of age: 1. control (CON) pelleted TMR without omega-3 oil supplementation; 2. omega-3 oil fortified pelleted TMR at 1% (MEOIL1) supplementation; and 3- Omega-3 oil fortified pelleted TMR at 3% (MEOIL3) supplementation. Supplementing MEOIL at both levels in diet positively impacted (p < 0.05) body weight (BW) and feed efficiency. At the end of feeding period, most carcass quality traits did not vary significantly (p > 0.05) among groups, with the exception of carcass dressing and loin yield at both levels of MEOIL. The color and physical traits of LL muscle were affected by MEOIL supplementation (p < 0.05), with no significant change in chemical characteristics. Fatty acids composition of meat in term of linolenic, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were significantly (p < 0.05) influenced by both levels of MEOIL. It was concluded that the tested microencapsulated omega-3 oil preparation may be included at 1% in lamb diet for increasing unsaturated fatty acids in meat without any detrimental effects on lamb productivity.

Technological Feasibility of Couscous-Algae-Supplemented Formulae: Process Description, Nutritional Properties and In Vitro Digestibility

The aim of this work was to develop functional couscous in a traditional Tunisian manner (hand rolling), enriched in algae biomass (6% w/w). Four Chlorella vulgaris (C. vulgaris) biomasses and one mixture of C. vulgaris and two macroalgae biomasses (Ulva rigida and Fucus vesiculosus) were used. The C. vulgaris strain was subjected to random mutagenesis and different culture conditions (Allmicroalgae), resulting in different pigmentations and biochemical compositions. Couscous samples were characterized in terms of nutritional properties, oscillatory rheology properties and digestibility. All biomasses provided a significant supplementation of nutrients and excellent acceptance. The enrichment resulted in lower firmness, higher viscoelastic functions (G' and G″) and a significant improvement in the cooking quality. Major differences between couscous samples with different microalgae were observed in protein and mineral contents, fully meeting Regulation (EC) No. 1924/2006 requirements for health claims made on foodstuffs. The amount of digested proteins was also higher in algae-containing samples. The fatty acid profile of the enriched couscous varied in a biomass-specific way, with a marked increase in linolenic acid (18:3 ω3) and a decrease in the ω6/ω3 ratio. Sensory analysis revealed that microalgae-containing products could compete with conventional goods with an added advantage, that is, having an ameliorated nutritional value using algae as a "trendy" and sustainable ingredient.

Fatty acid metabolism in lambs supplemented with different condensed and hydrolysable tannin extracts

Five groups of lambs (n = 9 each) were used to test the effect of plant extracts rich in hydrolysable (HT) or condensed tannin (CT) on animal performance, fatty acid composition of rumen content, liver and meat. The control group (CO) received a concentrate-based diet without tannins supplementation. The other groups received the same diet as the control lambs plus 4% chestnut (CH) and tara (TA) extracts as a source of HT and mimosa (MI) and gambier (GA) extracts as a source of CT. One-way ANOVA was used to assess the overall effect of dietary treatments, tannins supplementation (CO vs. CH+TA+MI+GA) and the effect of tannin type (HT vs. CT: CH+TA vs. MI+GA) on animal performance, rumen content, liver and intramuscular FA. Dietary CH negatively affected animal performance. The rumen content of the different groups showed similar levels of 18:3 c9c12c15, 18:2 c9c12, 18:2 c9t11, 18:1 t11 and 18:0, whereas 18:1 t10 was greater in CO. Also, 18:1 t10 tended to be lower in the rumen of HT than CT-fed lambs. These data were partially confirmed in liver and meat, where CO showed a greater percentage of individual trans 18:1 fatty acids in comparison with tannins-fed groups. Our findings challenge some accepted generalizations on the use of tannins in ruminant diets as they were ineffective to favour the accumulation of dietary PUFA or healthy fatty acids of biohydrogenation origin in the rumen content and lamb meat, but suggest a generalized influence on BH rather than on specific steps.

Trans-10 18:1 in ruminant meats: A review

Trans (t) fatty acids (TFA) from partially hydrogenated vegetable oils (i.e., industrial trans) have been phased out of foods in many countries due to their promotion of cardiovascular disease. This leaves ruminant-derived foods as the main source of TFA. Unlike industrial TFA where catalytic hydrogenation yields a broad distribution of isomers, ruminant TFA are enzymatically derived and can result in enrichment of specific isomers. Comparisons between industrial and ruminant TFA have often exonerated ruminant TFA due to their lack or at times positive effects on health. At extremes, however, ruminant-sourced foods can have either high levels of t10- or t11-18:1, and when considering enriched sources, t10-18:1 has properties similar to industrial TFA, whereas t11-18:1 can be converted to an isomer of conjugated linoleic acid (cis(c)9,t11-conjugated linoleic acid), both of which have potential positive health effects. Increased t10-18:1 in meat-producing ruminants has not been associated with negative effects on live animal production or meat quality. As such, reducing t10-18:1 has not been of immediate concern to ruminant meat producers, as there have been no economic consequences for its enrichment; nevertheless at high levels, it can compromise the nutritional quality of beef and lamb. In anticipation that regulations regarding TFA may focus more on t10-18:1 in beef and lamb, the present review will cover its production, analysis, biological effects, strategies for manipulation, and regulatory policy.

Effects of ecotrofin™ on milk yield, milk quality and serum biochemistry in lactating goats

A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega‐6:omega‐3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, p < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed.

Evaluating the Inclusion of Cold-Pressed Rapeseed Cake in the Concentrate for Dairy Cows upon Ruminal Biohydrogenation Process, Ruminal Microbial Community and Milk Production and Acceptability

The aim of this trial was to assess the effect of feeding a concentrate including cold-pressed rapeseed cake (CPRC) on productive performance, milk quality and its sensory properties, ruminal biohydrogenation, and bacterial communities. Eighteen cows were paired, and two experimental diets (control vs. CPRC) were distributed within the pair. Concentrates were iso-energetic and iso-proteic and contained similar amounts of fat. The average days in milk, milk yield, and body weight of the animals were (mean ± SD) 172 ± 112 d, 585 ± 26 kg, and 25.4 ± 6.2 kg/d, respectively. The experiment lasted for 10 wk. Feeding CPRC resulted in lower ruminal saturated (p < 0.001) and higher monounsaturated (p = 0.002) fatty acids. Feeding CPRC increased Ruminococcus, Prevotella, and Entodinium but decreased Blautia; p-75-a5; undefined genera within orders Clostridiaceae and RF39 and within families Christensenellaceae, Lachnospiracease, and Ruminococcaceae; and fungi from the phylum neocallimastigomycota. The milk fatty acid profile was characterized by a lower n6:n3 ratio (p = 0.028). Feeding CPRC did not affect the milk yield, milk quality, or fat corrected milk (p > 0.05). Feeding CPRC improved the overall milk acceptability (p = 0.047). In conclusion, CPRC affected some microbial taxa, modified the biohydrogenation process, and improved the milk fatty acid profile and consumer acceptance without detrimental effects on milk production and composition.

Productive Performance and Meat Characteristics of Kids Fed a Red Orange and Lemon Extract

Simple Summary

Small ruminant farming can potentially adopt low-input strategies by using agro-industrial byproducts as alternative feeding sources. Byproducts are natural, and thus are preferred by consumers because most of them have antioxidant activity that may improve different aspects linked to meat quality and human health. For this reason, a red orange and lemon extract, (RLE) rich in anthocyanins, is tested as an oral additive on kids’ meat. No differences were recorded on animal performance, but on meat, RLE inclusion improves juiciness and reduces color deterioration. Moreover, RLE reduced cooking loss, and meat quality is positively influenced, due to both delaying lipid oxidation and a better fatty acid profile resulting in healthier meat for human consumption.

Abstract

This study evaluates the animal performance and meat characteristics of 60 Saanen suckling kids daily fed a red orange and lemon extract (RLE), rich in anthocyanins. In our methodology, after colostrum administration, animals are randomly assigned to two treatments: Treatment group (Group RLE; n = 30) that received RLE (90 mg/kg live body weight) as oral food additive, and a control group (Group CON; n = 30) that received a standard diet. Animals are slaughtered after 40 days. The RLE administration did not influence daily weight gain, carcass measurements, or incidences (expressed as a percentage) of different anatomical regions on the whole carcass weight. On the contrary, RLE supplementation significantly improved the oxidative profile of the meat seven days after slaughtering, as demonstrated by the reduced levels of thiobarbituric acid reactive substances (TBARS; p < 0.01) and hydroperoxides (p < 0.01) in Group RLE compared to Group CON. A significant influence of RLE administration is observed on day 7 for yellowness (p < 0.01). There are also lower saturated and higher monounsaturated and polyunsaturated fatty acids concentration in Group RLE meat (p < 0.01), which also shows lower atherogenic and thrombogenic indexes (p < 0.01) compared to Group CON. The study demonstrates that the supplementation of a diet with RLE rich in anthocyanins is effective to improve the meat quality.

Effects of Increasing Doses of Condensed Tannins Extract from Cistus ladanifer L. on In Vitro Ruminal Fermentation and Biohydrogenation

Simple Summary

Ruminant edible products have been associated with adverse health effects, due to their high saturated fatty acids and low polyunsaturated fatty acids content, resulting from the extensive biohydrogenation conducted by rumen microbiota. Cistus ladanifer condensed tannins were able to change the lamb ruminal biohydrogenation, increasing the beneficial fatty acids production. The aim of this study was to test the effect of increasing doses of C. ladanifer condensed tannins extract (0, 25, 50, 75 and 100 g/kg dry matter) on in vitro rumen fermentation and biohydrogenation. The increasing doses of condensed tannins led to a moderate decrease of volatile fatty acids production, a pronounced depression in microbial odd and branched fatty acids and of dimethyl acetals production, and a minor effect on the biohydrogenation, which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities. The ability of C. ladanifer condensed tannins extract to modulate the biohydrogenation (BH) was not observed in the present study. However, the results obtained suggest a possible adaptative response of the microbial population to stress stimuli of condensed tannins and lipid supplementation.

Abstract

Cistus ladanifer (rockrose) is a perennial shrub quite abundant in the Mediterranean region, and it is a rich source in secondary compounds such as condensed tannins (CTs). Condensed tannins from C. ladanifer were able to change the ruminal biohydrogenation (BH), increasing the t11–18:1 and c9,t11–18:2 production. However, the adequate conditions of the C. ladanifer CTs used to optimize the production of t11–18:1 and c9,t11–18:2 is not yet known. Thus, we tested the effect of increasing the doses of C. ladanifer CT extract (0, 25, 50, 75 and 100 g/kg dry matter (DM)) on in vitro rumen BH. Five in vitro batch incubations replicates were conducted using an oil supplemented high-concentrate substrate, incubated for 24 h with 6 mL of buffered ruminal fluid. Volatile fatty acids (VFAs) and long chain fatty acids (FA) were analyzed at 0 h and 24 h, and BH of c9–18:1, c9, c12–18:2 and c9, c12, c15–18:3, and BH products yield were computed. Increasing doses of C. ladanifer CTs led to a moderate linear decrease (p < 0.001) of the VFA production (a reduction of 27% with the highest dose compared to control). The disappearance of c9–18:1 and c9,c12–18:2 as well as the production of t11–18:1 and c9, t11:18:2 was not affected by increasing doses of C. ladanifer CTs, and only the disappearance of c9, c12, c15–18:3 suffered a mild linear decrease (a reduction of 24% with the highest dose compared to control). Nevertheless, increasing the C. ladanifer CT dose led to a strong depression of microbial odd and branched fatty acids and of dimethyl acetals production (less than 65% with the highest dose compared to control), which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities, in a possible adaptative response of microbial population to stress induced to CTs and polyunsaturated fatty acids. The ability of C. ladanifer to modulate the ruminal BH was not verified in the current in vitro experimental conditions, emphasizing the inconsistent BH response to CTs and highlighting the need to continue seeking the optimal conditions for using CTs to improve the fatty acid profile of ruminant fat.

Feeding Algae Meal to Feedlot Lambs with Competent Reticular Groove Reflex Increases Omega-3 Fatty Acids in Meat

The aim of this study was to compare the effects of supplementing marine algae as a source of omega-3 fatty acids (FA) in the diet, mixed in the concentrate or bottle-fed, on intramuscular fat FA composition of lambs with competent reticular groove reflex (RGR). Forty-eight feedlot lambs were distributed in three equal groups: one group did not consume marine algae nor had competent RGR, the second group received a daily dose (2.5%) of algae meal in the concentrate and the last group consumed the same dose of algae meal emulsified in milk replacer and bottle-fed. Marine algae raised the contents of EPA, DPA, and mainly DHA in the intramuscular fat, but the increase was significantly higher when algae meal was administered with a bottle via RGR. This strategy could contribute to improvements in the marketing of lamb meat by optimizing its status as a healthier food.

Discrimination of Meat Produced by Bos taurus and Bos indicus Finished under an Intensive or Extensive System

Simple Summary

This research was carried out to investigate the usefulness and reliability of meat quality traits such as physicochemical properties and fatty acid profiles to discriminate between meat produced by taurine and zebu cattle, finished on pasture or grain. This approach is of utmost importance to assess the authenticity of meat products, particularly when beef is certified based on criteria such as breed and finishing system. Our results using discriminant analyses indicate that meats originating from pasture- or grain-finishing can be discriminated with high reliability, essentially on the basis of their fatty acid profile. The global distinction of meat from the two genetic groups is somewhat more difficult to achieve reliably. Still, prior knowledge of the finishing system used to produce meat from a given genetic group enhances the trustworthiness of the assignment procedure, allowing the reliable allocation of meat samples originating from Bos indicus and Bos taurus finished on pasture or grain, with fatty acid profiles being better discriminating factors than physicochemical properties. These results can be adopted as tools to be used in meat certification programs.

Abstract

Meat obtained under commercial conditions shows considerable variability, mostly due to genetic background and production system. In this study, meat physicochemical properties and fatty acid profiles were analysed to investigate the feasibility of using them as tools to discriminate between meats produced by different genetic groups and finishing systems. Samples of the Longissimus thoracis were collected from 160 commercial bulls of the B. taurus (n = 75) and B. indicus (n = 85) groups, finished either on pasture (n = 46) or with grain supplementation (n = 114) and analysed by standard procedures. Data were analysed by discriminant analysis using a stepwise procedure, to select the meat characteristics that better contribute to discriminate the various groups. Our results indicate that fatty acid profiles of meat had better discriminating ability than physicochemical properties, especially to identify meat from animals finished on grain or pasture. The overall discrimination of meat from different genetic groups was achieved with a slightly lower reliability. Nonetheless, our results show that reliability of allocation to genetic group can be improved if prior information on finishing system is considered. These results are of high importance because they can be incorporated as tools to assess the authenticity of beef, particularly in meat certification programs.

Increasing the α-tocopherol content and lipid oxidative stability of meat through dietary Cistus ladanifer L. in lamb fed increasing levels of polyunsaturated fatty acid rich vegetable oils

The aim of this study was to evaluate the effect of the dietary inclusion of Cistus ladanifer L. and vegetable oils on intramuscular fat composition, muscle antioxidant status and lipid oxidative stability, and explore the mechanism by which dietary Cistus ladanifer limits the lipid oxidation. Lambs were assigned 9 diets, corresponding to 3 levels of Cistus ladanifer (50, 100 and 200 g/kg DM) and 3 levels of oil (0, 40 and 80 g/kg DM). Oil supplementation increased highly peroxidizable fatty acid content and the peroxidizability index (P < .05). Muscle phenolic content, reducing ability and radical scavenging ability were not affected by Cistus ladanifer (P > .05). The highest level of Cistus ladanifer enhanced muscle resistance to lipid oxidation (P = .006) and increased α-tocopherol content (P = .005), reducing meat lipid oxidation over 7 days of storage (P < .001). Results showed that Cistus ladanifer has a protective effect against lipid oxidation through increasing α-tocopherol concentration in the muscle.

Highly selective isomerization of cottonseed oil into conjugated linoleic acid catalyzed by multiwalled carbon nanotube supported ruthenium

Supported ruthenium (Ru) has the capacity to catalyze the conjugation of double bonds in linoleic acid (LA) into conjugated linoleic acids (CLAs). It has been reported that CLAs have shown a lot of benefits to human health. To enhance the selectivity of cottonseed oil (CSO) to CLAs, various Ru catalysts supported by multiwalled carbon nanotubes (Ru/MWCNTs) were prepared using a microwave-heated ethylene glycol method. All catalysts were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectrometry (ICP-OES). The catalytic efficiency/selectivity of Ru/MWCNTs and two commercially available Ru catalysts (Ru/C and Ru/Al₂O₃) were investigated in a solvent-free system by catalyzing the isomerization of CSO. TEM analysis showed that Ru nanoparticles with average sizes of 1.0 nm to 1.8 nm were uniformly dispersed on the surface of the supports. Among the as-synthesized Ru/MWCNTs, catalyst S1 (diameter < 8 nm, length 0.5–2 μm) and catalyst S4 (diameter < 8 nm, length 10–30 μm) exhibit excellent catalytic performance for isomerization of CSO with high yield of total CLA (15.91% and 11.56%, respectively) and high turnover frequency (TOF) of 10.39 and 11.38 h⁻¹, which is much better than two typical commercial Ru catalysts (Ru/Al₂O₃ and Ru/C). It has been revealed that the average particle size and chemical state of Ru on the surface of MWCNTs have influence on the activity and selectivity of the isomerization reaction.

Ruthenium supported on multiwalled carbon nanotubes is a highly efficient catalyst for the linoleic acid conjugation of cottonseed oil.

Effect of Linseed Supplementation on Total Longissimus Muscle Lipid Composition and Shelf-Life of Beef From Young Maremmana Bulls

Twenty young Maremmana bulls were randomly allotted to two dietary groups during a finishing period (~90 days): C diet (without lipid supplementation), and L diet (with linseed supplementation, 20% concentrate feed). The aim was to investigate the effects of dietary linseed supplementation on the intramuscular fat composition, and the shelf-life of minced beef. The L diet did not alter the dressing rate and daily weight gain, whereas the C18:3n-3 content in the intramuscular fat significantly increased (from 0.85 to 1.78 g/100 g of total fatty acid, +109%), leading to a reduction in a n-6/n-3 ratio below four and an increase in the overall proportion of long chain n-3 fatty acids in beef lipids. These effects were principally related to differences in the distribution of fatty acids between the neutral and polar lipids. The results demonstrated that linseed supplementation modified the lipid composition of beef, without negatively impacting overall productivity, in the period from weaning the bull until its slaughter. However, the total amount of n-3 fatty acids in the beef of young bulls on the L diet, was not sufficient for the aliquot of humans' n-3 fatty acid requirements. This was mainly related to the low levels of fat in the beef. Comparing beef samples from animals on the L diet, with samples from animals on the C diet, the higher levels of n-3 polyunsaturated fatty acids led to a significant reduction of shelf-life starting after 2 days of storage at 4°C, because of fatty acid and cholesterol oxidation. The L diet group samples showed a higher level of TBARS (+80%) and COPs (+73%), two important parameters to estimate the oxidation level of beef. This suggests that enriching beef with n-3 fatty acids should be coupled with packaging techniques that consider the higher susceptibility to lipid oxidation. In conclusion, dietary linseed supplementation led to a higher proportion of n-3 fatty acids in beef lipids, however, the natural content of antioxidant substances was not able to protect intramuscular fat from oxidation during storage at 4°C.

Growth performance, carcass and meat quality of lambs supplemented different vegetable oils

Objective

The purpose of this study was to evaluate the effect of rapeseed and linseed oil supplementations on performance and meat quality of lambs.

Methods

The experiment was conducted on 18 growing (100-day-old) lambs of 19.7±1.9 kg live weight, assigned to 3 groups of 6 animals each. Control lambs were fed meadow hay and concentrate alone. Experimental animals additionally received rapeseed or linseed oils at a dose of 50 g/d. The lambs were slaughtered at an average body weight of 35.7±0.5 kg.

Results

The dressing percentage was higher in lambs fed rapeseed oil. Total saturated fatty acids (SFA) and C15:0, C16:0, C17:0, C21:0, C24:0 were lower in longissimus dorsi muscle (MLD) in lambs fed linseed oil. Supplementation of diet with linseed oil decreased concentrations of total monounsaturated fatty acids and C16:1, C17:1, C18:1 cis-9 in MLD. The concentrations of n-3 polyunsaturated fatty acids (PUFA) and C18:3 n-3, C20:5 n-3 in MLD were higher in lambs fed linseed oil than in other groups. Oils supplementation to diets resulted in increased concentration of C22:6 n-3 in MLD. The inclusion of linseed oil into the diet increased the contents of total PUFA, n-3 PUFA and C18:3 n-3, C20:5 n-3, C22:6 n-3 in semitendinosus muscle in comparison to control. A tendency towards a lower n:6/n:3 ratio in MLD was observed when lambs were supplemented linseed oil.

Conclusion

The supplementation of linseed oil to diets seems to reduce the concentration of SFA and increase the concentration of n-3 PUFA. The n-6/n-3 ratio is an important nutritional factor, and its value has been favorably decreased below 2, thereby achieving an important target related to human health. Due to these changes carcass fatty acid profile was improved, and so enhanced lamb meat healthy properties.

Effect of Diet Supplementation with Quinoa Seed and/or Linseed on Immune Response, Productivity and Meat Quality in Merinos Derived Lambs

Simple Summary

Stressful conditions can play an important role in affecting welfare, productive performances and meat quality of lambs. The relation between nutrition and immune response has been investigated in the livestock production, particularly in dairy cattle and sheep. Due to costs related to animal feed it is useful to evaluate the proper feeding strategy supplementation for improving animal welfare and lamb meat quality. The present study aimed to evaluate the effects of supplementation with linseed, quinoa seed and their combination on metabolic profile, immune system, and cortisol response in blood and on meat quality of merinos derived lambs. Both linseed and quinoa supplementation enhanced the immune responses of lambs, and showed a hypo cholesterol effect on blood of lambs. Moreover, lambs supplemented with linseed resulted in the lowest level of cortisol secretion during the loading test demonstrating the link between stress and the immune system. In addition, data from the present experiment highlighted that linseed supplementation in lambs enhance meat quality producing a better meat tenderness. These findings should be considered for development of specific strategies aimed at improving the quality of meat and sustaining lambs’ welfare.

Abstract

In the last years several studies have investigated the strong relation between nutrition and immune response in the livestock production, particularly in dairy cattle and sheep. The aim of this study was to evaluate the effects of supplementation based on linseed, quinoa seeds and their combination on welfare, productivity and quality of meat from merinos derived lambs. 32 weaned lambs were divided into 4 experimental groups: quinoa (Q), linseed (LS) and combination of quinoa and linseed (LS + Q) that received the respective supplementation and control group (C) without supplementation. Lambs from all supplemented groups showed lower plasma urea, creatinine and cholesterol than control. Both linseed and quinoa supplementation enhanced the cell-mediated immune responses of lambs, furthermore, linseed supplementation resulted in the lowest level of cortisol secretion after handling, loading and transport. Meat from lambs supplemented with linseed and LS + Q showed the highest pH, at 1 and 3 h post-mortem, while, meat from all supplemented groups was more tender than meat from control. Results indicated that linseed and quinoa seeds supplementation can help the animal to cope with stressful events due to the close link between stress responses and the immune system and for improving meat quality in terms of better tenderness.

Dietary supplementation with Essential-oils-cobalt for improving growth performance, meat quality and skin cell capacity of goats

Essential oils (EO) are secondary metabolites usually made up of terpenoids and phenylpropanoids and have antimicrobial properties. However, the feeding effects of EO-Cobalt (EOC) on the performance of goats are largely unknown. Herein we investigated and reported the effects of dietary EOC (0, 52, and 91 mg daily) on fiber producing cashmere goats. We determined the resulting phenotypes including live growth, carcass weight, meat quality, and cashmere fiber traits. We show that dietary supplement of EOC significantly promoted average daily gain (P < 0.05), and significantly improved carcass weight, and meat and hair fiber quality (P < 0.05). We further conducted RNA-seq using skin and liver tissues from each group to assess the molecular mechanism conferring these phenotypic changes. A total of 191 differentially expressed genes were found in the skin tissues (0 vs 91 mg), while 1,127 DEGs were found in livers. Analyses of liver samples for differential gene action and functional prediction found that EOC stimulated physiological changes in the body’s immune system at both blood and cell levels. Our results demonstrated the potential of using EO-based feed ingredient to improve animal growth performance, meat quality and fiber quality, and further illustrated the molecular basis that contribute to phenotypes at physiological levels.

Effects of dietary n-6: n-3 polyunsaturated fatty acid ratios on meat quality, carcass characteristics, tissue fatty acid profiles, and expression of lipogenic genes in growing goats

The present study was conducted to investigate the effects of altering the ratio of n-6 to n-3 fatty acids in the diet on meat quality, fatty acid composition of muscle, and expression of lipogenic genes in the muscle of Boer goats. A total of twenty-one Boer goats (5 months old; 31.66±1.07 kg body weight) were randomly assigned to three dietary treatments with n-6:n-3 fatty acid ratios of 2.27:1 (LR), 5.01:1 (MR) and 10.38:1 (HR), fed at 3.7% of body weight. After 100 days of feeding, all goats were slaughtered and the longissimus dorsi muscle was sampled for analysis of fatty acids and gene expression. The dietary treatments did not affect (P>0.05) the carcass traits, and meat quality of growing goats. The concentrations of cis-9,trans-11 conjugated linoleic acid, trans vaccenic acid, polyunsaturated fatty acids, and unsaturated/saturated fatty acid ratios linearly increased (P<0.01) with decreasing dietary n-6:n-3 fatty acid ratios, especially for LR in the longissimus dorsi muscle of goats. In contrast, the mRNA expression level of the PPARα and PPARγ was down-regulated and stearoyl-CoA desaturase up-regulated in the longissimus dorsi of growing goats with increasing dietary n-6:n-3 fatty acid ratios (P<0.01). In conclusion, the results obtained indicate that the optimal n-6:n-3 fatty acid ratio of 2.27:1 exerted beneficial effects on meat fatty acid profiles, leading towards an enrichment in n-3 polyunsaturated fatty acids and conjugated linoleic acid in goat intramuscular fat.

Effects of dietary supplementation with polyphenols on meat quality in Saanen goat kids

Background

Diet supplementation with polyphenols is a novel strategy to improve meat quality in livestock, by preventing oxidative deterioration of lipids and protein. Polyphenols have beneficial effects on both human and animal health and can be obtained from several sources, such as olive mill wastewaters (OMWW). These are severe environmental pollutants and therefore may be recycled and utilized in other sectors. The aim of this study was to evaluate growth performance, meat characteristics, fatty acid composition, antioxidant status, different forms of myoglobin and malondialdehyde formation in kids who received a diet supplemented with polyphenols obtained from OMWW. Weaned goat kids (n = 18) were divided into two homogenous groups: control (C) group (n = 9) received a fattening standard diet while the other group (n = 9) received the same diet, supplemented with 3.2 mg/day of polyphenols powder extract (PE group). Average daily gain (ADG) was calculated 10 days apart throughout the study. After 78 days, the kids were slaughtered and pH and carcass yield were evaluated. Longissimus thoracis et lumborum muscle was collected and utilized for chemical analysis, meat quality evaluation and oxidative stability.

Results

No differences were recorded in ADG, carcass weight, pH and dressing between the two groups. Furthermore a similar meat proximate composition, texture and color was observed. Dietary polyphenols supplementation significantly (P < 0.01) decreased short chains (<C12:0) (2.93 + 0.50 and 0.35 + 0.40 g/100 g of fatty acids, for C and PE Group, respectively), and saturated (49.22 ± 2.39 and 39.51 ± 1.95 g/100 g, in C and PE Group, respectively) fatty acids. Furthermore, a higher (P < 0.05) proportion of monounsaturated (34.35 ± 2.84 and 42.22 ± 2.32 g/100 g, in C and PE Group, respectively) fatty acids was recorded. Malondialdehyde formation was significantly (P < 0.05) lower in PE compared to C Group (0.25 ± 0.005 and 0.15 ± 0.005, in C and PE Group, respectively).

Conclusions

Polyphenols dietary supplementation has positive effects on kid meat, improving fatty acid profile and reducing malondialdehyde contents. Furthermore the utilization of OMWW as the source of polyphenols may represent an innovative strategy to re-utilize agri-food industry wastes.

Dried tomato pomace supplementation to reduce lamb concentrate intake: Effects on growth performance and meat quality

The effect of dried tomato pomace (DTP) was tested on lamb performances, meat fatty acids and oxidative stability. For 36 days, one group of lambs (n = 7; CON) was fed a commercial concentrate, while the other group (n = 7; DTP) received DTP in addition to CON diet. The administration of DTP reduced (P < .05) concentrate intake, with no effect on animal performances. The DTP treatment tended to increase total polyunsaturated fatty acids (PUFA; P = .075), PUFA n-6 (P = .071), α-linolenic acid (P = .096) and increased linoleic acid (P < .05), γ-tocopherol (P < .001) and retinol (P < .001) in meat. In raw meat, DTP treatment increased L* (P = .059), b* (P < .05), C* (P = .052) and H* (P < .05) values compared to CON, while lipid oxidation was not affected. In meat homogenates incubated with pro-oxidants, DTP tended to reduce 2-thiobarbituric acid reactive substances (TBARS; P = .088). Therefore, DTP supplementation decreased the consumption of commercial concentrate without detrimental effects on animal performances and meat quality traits.

Dietary supplementation of different parts of Andrographis paniculata affects the fatty acids, lipid oxidation, microbiota, and quality attributes of longissimus muscle in goats

The effects of dietary supplementation of different parts of Andrographis paniculata on fatty acids, lipid oxidation, microbiota and quality attributes of Longissimus thoracis et lumborum (LTL) muscle in goats were assessed. Twenty four, entire Boer bucks (4 months old; 20.18 ± 0.19 kg BW) were randomly allotted to either a basal diet without additive (AP0), a basal diet + 1.5% Andrographis paniculata leaves (APL) or a basal diet + 1.5% Andrographis paniculata whole plant (APW). The bucks were fed the diets for 100 d and slaughtered. The LTL muscle was subjected to a 7 d chill storage. The AP0 meat had higher (p < .05) concentration of C16:0 and C18:0 than the APW and APL meat. The concentrations of total C18:1trans, total CLA, C18:1n-9, C18:2n-6, C18:3n-3 and C20:5n-3 were higher (p < .05) in APL and APW meat than the AP0 meat. Diets had no effect (p > .05) on muscle glycogen, pH, drip loss, chemical composition and lactic acid bacteria count. Cooking loss, shear force, and TBARS values were lower (p < .05) in APL (23.98%, 0.76 kg, 0.12 mg MDA/kg) and APW (24.53%, 0.80 kg, 0.15 mg MDA/kg) meat compared with AP0 (26.49%, 1.13 kg, 0.23 mg MDA/kg) meat. Meat redness was higher (p < .05) in APL (13.49) and APW (12.98) than AP0 (10.86). Sensory scores for juiciness, tenderness, and overall acceptability of APL (7.92, 7.88, 7.89) and APW (7.90, 7.08, 7.77) meat were higher (p < .05) than that of the AP0 (5.38, 5.95, 5.41) meat. Total viable counts and populations of Pseudomonas spp, Escherichia coli and Enterobacteriacea were higher (p < .05) in AP0 meat than in APL and APW meat. The APL exhibited higher (p < .05) antimicrobial potential than the APW. Chill storage affected (p < .05) the physicochemical properties, lipid oxidation and microbial counts in chevon. Dietary APL and APW enhanced the beneficial fatty acids, quality attributes and oxidative stability, and reduced microbial counts in chevon.

Does growth path influence beef lipid deposition and fatty acid composition?

Despite the recent advances in transcriptomics, gene expression studies addressing cattle´s skeletal muscle adaptations in response to compensatory growth are warranted, particularly regarding lipid metabolism due to its impact in meat sensory and nutritional traits. In the present study, in comparison to ad libitum feeding, a period of feed restriction was used in order to understand the changes in bull´s lipid metabolism and gene expression of the adipogenic and lipogenic pathways after re-alimentation. Thus, 40 young Alentejana bulls were either fed ad libitum (CG group) from 9 to 18 months of age or subjected to food restriction from 9 to 15 months of age, and fed ad libitum until 24 months of age (DG group). The intramuscular fat (IMF) and total fatty acids (FA) contents were similar between groups. The major FA (>2%) contents were similar (16:0, 16:1c9, 18:1c9 and 18:2n-6) between treatments with the exception of 18:0 content that was 15% lower in DG than in CG and 20:4n-6 that tended to be greater on DG bulls. Regarding minor FA (<2%), the DG group presented greater proportions (P<0.01) of 17:1c9, 18:1t9, 18:1t10 (, 18:1c11), 18:1c13, 18:3n-6, 22:0, 22:4n-6 and 22:6n-3 and lower (P<0.05) proportions of 20:0, 18:1t16+c14, and branched chain FA (iso-15:0, anteiso-15:0, iso-16:0 and anteiso-17:0) than the CG group. Delta-9 desaturase activity indices were consistently greater (P<0.05) in DG, when compared to the CG group. Regarding microarray analysis, differentially expressed genes between CG and DG bulls were grouped in 5 main biological functions: lipid and nucleic acid metabolisms, small molecule biochemistry, molecular transport and translational modification. Discontinuous growth down-regulated the expression of ACACB (FC (fold-change) = 1.32), FABP3 (FC = 1.45), HADHA (FC = 1.41) and SLC37A4 (FC = 1.40) genes, when compared to the CG system (FDR<0.05). In contrast, in the CG bulls, the expression of ELOVL5 (FC = 1.58) and FASN (FC = 1.71) was down-regulated when compared to DG bulls. These results were confirmed to be significant (P<0.05) in the case of ELOVL5, FASN and SLC37A4, and almost significant for FABP3 by qRT-PCR analysis. The SCD1 and SCD5 gene expressions were not found to be affected by growth path. These results contribute to the still scarce knowledge about the mechanisms involved in fatty acid metabolism during compensatory growth which have decisive role on meat quality produced in Mediterranean areas.

Effects of dietary inclusion of citrus pulp and rockrose soft stems and leaves on lamb meat quality and fatty acid composition

Meat from lambs finished with high-starch diets often contains low concentration of vaccenic (t11-18:1) and rumenic (c9,t11-18:2) acids and high concentration of t10-18:1. We hypothesized that replacing cereals by dehydrated citrus pulp (DCP) and the inclusion of tanniferous feed sources in oil supplemented diets might reduce the accumulation of t10-18:1 and increase the t11-18:1 and c9,t11-18:2 in lamb meat, without affecting the productive performance. In total, 32 lambs were assigned to four diets which combine two factors: basal diet (BD) (cereals v. DCP) and Cistus ladanifer (CL) (0 v. 150 g/kg dry matter). Feed intake, average daily weight gain and carcass traits were not affected by treatments, except for dressing percentage that was reduced with DCP (P=0.046). Both DCP and C. ladanifer reduced tenderness and juiciness of meat, and C. ladanifer also reduced (P0.05) by diets. However, DCP increased the proportions of odd-chain FA (P=0.005) and several minor biohydrogenation (BH) intermediates in meat lipids. C. ladanifer had few effects on meat FA profile. The proportions of t11-18:1 and c9,t11-18:2 were high in all diets (5.4% and 1.5% of total FA, respectively) and were not influenced by the treatments. Basal diet and CL showed some significant interactions concerning FA composition of intramuscular fat. In diets without C. ladanifer, replacement of cereals by DCP increased the 18:0 (P<0.05) and decreased t10,c12-18:2 (P<0.05), t10-18:1 (P<0.10) and t10-/t11-18:1 ratio (P<0.10) with a large reduction of the individual variation for t10-18:1 and of t10-/t11-18:1 ratio. Combined with cereals, C. ladanifer increased 18:0 and reduced the BH intermediates in meat. Replacement of cereals by DCP seems to promote a more predictable FA profile in lamb meat, reducing the risk of t10-shifted BH pathways in the rumen.

Can we improve the nutritional quality of meat?

The nutritional value of meat is an increasingly important factor influencing consumer preferences for poultry, red meat and processed meat products. Intramuscular fat content and composition, in addition to high quality protein, trace minerals and vitamins are important determinants of nutritional value. Fat content of meat at retail has decreased substantially over the past 40 years through advances in animal genetics, nutrition and management and changes in processing techniques. Evidence of the association between diet and the incidence of human non-communicable diseases has driven an interest in developing production systems for lowering total SFA and trans fatty acid (TFA) content and enrichment of n-3 PUFA concentrations in meat and meat products. Typically, poultry and pork has a lower fat content, containing higher PUFA and lower TFA concentrations than lamb or beef. Animal genetics, nutrition and maturity, coupled with their rumen microbiome, are the main factors influencing tissue lipid content and relative proportions of SFA, MUFA and PUFA. Altering the fatty acid (FA) profile of lamb and beef is determined to a large extent by extensive plant and microbial lipolysis and subsequent microbial biohydrogenation of dietary lipid in the rumen, and one of the major reasons explaining the differences in lipid composition of meat from monogastrics and ruminants. Nutritional strategies can be used to align the fat content and FA composition of poultry, pork, lamb and beef with Public Health Guidelines for lowering the social and economic burden of chronic disease.

Degummed crude canola oil, sire breed and gender effects on intramuscular long-chain omega-3 fatty acid properties of raw and cooked lamb meat

Background

Omega-3 long-chain (≥C₂₀) polyunsaturated fatty acids (ω3 LC-PUFA) confer important attributes to health-conscious meat consumers due to the significant role they play in brain development, prevention of coronary heart disease, obesity and hypertension. In this study, the ω3 LC-PUFA content of raw and cooked Longissimus thoracis et lumborum (LTL) muscle from genetically divergent Australian prime lambs supplemented with dietary degummed crude canola oil (DCCO) was evaluated.

Methods

Samples of LTL muscle were sourced from 24 first cross ewe and wether lambs sired by Dorset, White Suffolk and Merino rams joined to Merino dams that were assigned to supplemental regimes of degummed crude canola oil (DCCO): a control diet at 0 mL/kg DM of DCCO (DCCOC); 25 mL/kg DM of DCCO (DCCOM) and 50 mL/kg DCCO (DCCOH). Lambs were individually housed and offered 1 kg/day/head for 42 days before being slaughtered. Samples for cooked analysis were prepared to a core temperature of 70 °C using conductive dry-heat.

Results

Within raw meats: DCCOH supplemented lambs had significantly (P < 0.05) higher concentrations of eicosapentaenoic (EPA, 20:5ω3) and EPA + docosahexaenoic (DHA, 22:6ω3) acids than those supplemented with DCCOM or DCCOC; Dorset sired lambs contained significantly (P < 0.05) more EPA and EPA + DHA than other sire breeds; diet and sire breed interactions were significant (P < 0.05) in affecting EPA and EPA + DHA concentrations. In cooked meat, ω3 LC-PUFA concentrations in DCCOM (32 mg/100 g), DCCOH (38 mg/100 g), Dorset (36 mg/100 g), White Suffolk (32 mg/100 g), ewes (32 mg/100 g) and wethers (33 mg/100 g), all exceeded the minimum content of 30 mg/100 g of edible cooked portion of EPA + DHA for Australian defined ‘source’ level ω3 LC-PUFA classification.

Conclusion

These results present that combinations of dietary degummed crude canola oil, sheep genetics and culinary preparation method can be used as effective management tools to deliver nutritionally improved ω3 LC-PUFA lamb to meat consumers.

Omega-3 Long-Chain Fatty Acids in the Heart, Kidney, Liver and Plasma Metabolite Profiles of Australian Prime Lambs Supplemented with Pelleted Canola and Flaxseed Oils

The objective of the study was to ascertain whether human health beneficial omega-3 long-chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) content in heart, kidney and liver can be enhanced by supplementing prime lambs with graded levels of canola and flaxseed oil. Health status of the lambs, as a consequence of the supplementation, was also investigated by examining their plasma metabolites. Sixty purebred and first-cross lambs were allocated to one of five treatments of lucerne hay basal diet supplemented with isocaloric and isonitrogenous wheat-based pellets without oil inclusion (Control) or graded levels of canola oil at 2.5% (2.5C), 5% (5C), flaxseed oil at 2.5% (2.5F) and 5% (5F) in a completely randomised design. Pre-slaughter blood, post-slaughter kidney, liver and heart samples were analysed for plasma metabolite and fatty acid profiles. Summations of docosapentaenoic acid and docosahexaenoic acid, and total n-3 LC-PUFA were enhanced in the liver and kidney of 5F supplemented lambs with a marked decrease in n-6/n-3 ratio and significant breed differences detected. There were generally no deleterious impacts on animal health status. A combination of 5% oil supplementation and lamb genetics is an effective and strategic management tool for enhancing n-3 LC-PUFA contents of heart, kidney and liver without compromising lamb health.

The reduction of starch in finishing diets supplemented with oil does not prevent the accumulation of trans-10 18:1 in lamb meat

The experiment was conducted to test the hypothesis that the replacement of cereal with low-starch feed ingredients in lambs' finishing diets supplemented with oils could prevent the accumulation of -10-18:1 in meat. Forty lambs were fed 1 of 4 diets supplemented with soybean oil (5.9%) and fish oil (1%) for 6 wk before slaughter. The control (CON) diet contained 43% barley, and in the other diets, barley was completely replaced by dehydrated citrus pulp (DCP), dehydrated sugar beet pulp (DBP), or soybean hulls (SH). Growth performance, feed intake, and carcass and meat quality traits were analyzed. At slaughter, LM samples were collected for gene expression evaluation, and 3 d after slaughter, LM and subcutaneous (s.c.) fat samples were collected for fatty acid analysis. None of the diets affected meat quality, but the DCP diet reduced ADG ( < 0.05) and the DCP and SH diets decreased the feed-to-gain ratio ( < 0.01). The DCP diet increased ( < 0.05) the risk of parakeratosis and the severity of the lesions. Moreover, the DBP treatment led to increased a* (redness) and b* (yellowness) in s.c. fat compared with the CON treatment ( < 0.05). The lipid content of LM did not differ ( > 0.05) with treatment and averaged 34.4 g/kg of meat. Diets had no effect ( > 0.05) on SFA, PUFA, and -MUFA sums and on the -6:-3 ratio in both LM and s.c. fat. A lower expression of fatty acid synthase (FASN) was found with the DCP treatment than with the other treatments ( < 0.001). All treatments showed a high accumulation of -10-18:1, averaging 91 mg/g fatty acid in LM and 147 mg/g fatty acid in s.c. fat. The concentration of -11-18:1 in the tissues was considerably lower than that of -10-18:1, and thus the -10-18:1:-11-18:1 ratio was above 3 with all treatments. Despite this, the SH diet clearly promoted a larger deposition of -11-18:1 and -9,-11-18:2 in tissues compared with the other treatments. () gene expression and SCD activity index in LM were reduced with the SH diet compared with the CON and DCP diets. Overall, these results clearly showed, for the first time, that low-starch/high-NDF diets are not able to prevent the establishment of -10 shifted rumen biohydrogenation pathways, evaluated by the deposition of biohydrogenation intermediates in lamb meat and fat.

Nutritional enhancement of sheep meat fatty acid profile for human health and wellbeing

Dietary fatty acids (FA) consumed by sheep, like other ruminants, can undergo biohydrogenation resulting in high proportions of saturated FA (SFA) in meat. Biohydrogenation is typically less extensive in sheep than cattle, and consequently, sheep meat can contain higher proportions of omega (n)-3 polyunsaturated FA (PUFA), and PUFA biohydrogenation intermediates (PUFA-BHI) including conjugated linoleic acid (CLA) and trans-monounsaturated FAs (t-MUFA). Sheep meat is also noted for having characteristically higher contents of branched chain FA (BCFA). From a human health and wellness perspective, some SFA and trans-MUFA have been found to negatively affect blood lipid profiles, and are associated with increased risk of cardiovascular disease (CVD). On the other hand, n-3 PUFA, BCFA and some PUFA-BHI may have many potential beneficial effects on human health and wellbeing. In particular, vaccenic acid (VA), rumenic acid (RA) and BCFA may have potential for protecting against cancer and inflammatory disorders among other human health benefits. Several innovative strategies have been evaluated for their potential to enrich sheep meat with FA which may have human health benefits. To this end, dietary manipulation has been found to be the most effective strategy of improving the FA profile of sheep meat. However, there is a missing link between the FA profile of sheep meat, human consumption patterns of sheep FA and chronic diseases. The current review provides an overview of the nutritional strategies used to enhance the FA profile of sheep meat for human consumption.

The effect of grapeseed oil on performance, rumen fermentation, antioxidant status and subcutaneous adipose fatty acid profile in lambs

This experiment was carried out to examine the effect of grapeseed oil (GSO) on performance, rumen fermentation, antioxidant status and subcutaneous adipose fatty acid (FA) profile in lambs. Eighteen Baluchi lambs, 196 ± 14 days of age and 39.8 ± 1.7 kg body weight, were randomly assigned to three experimental diets: (i) diet without GSO (control), (ii) diet containing 2% of GSO (GSO2) and (iii) diet containing 4% of GSO (GSO4) for 42 days. Results showed that the experimental diets had no significant effect on dry matter intake and performance (p > 0.05). The supplemented diets with GSO had no effect on pH and NH₃ -N of rumen fluid (p > 0.05), but GSO4 increased (p = 0.003) the concentration of propionic acid and reduced (p = 0.002) the concentration of acetate acid compared to the control. Inclusion 4% of GSO to the diet increased total antioxidant activity and decreased malondialdehyde in serum and muscle (p < 0.001). The level of blood glutathione peroxidase in diets containing GSO was higher than control diet (p = 0.02), but diets had no effect on superoxide dismutase in blood and muscle tissues (p > 0.05). The concentration of vaccenic acid, rumenic acid and linoleic acid and thus polyunsaturated fatty acid in subcutaneous fat was affected by experimental diets (p < 0.001), as control had the lowest amount of these FAs and GSO4 had the highest amount of them. Therefore, it can be concluded that the use of GSO up to 4% improves the antioxidant status and adipose fatty acid profile in lambs without effects on performance.

Dietary n-6:n-3 Fatty Acid Ratios Alter Rumen Fermentation Parameters and Microbial Populations in Goats

Revealing the ruminal fermentation patterns and microbial populations as affected by dietary n-6:n-3 PUFA ratio would be useful for further clarifying the role of the rumen in the lipid metabolism of ruminants. The objective of the present study was to investigate the effects of dietary n-6:n-3 PUFA ratios on fermentation characteristics, fatty acid (FA) profiles, and microbial populations in the rumen of goats. A total of twenty-one goats were randomly assigned to three dietary treatments with different n-6:n-3 PUFA ratios of 2.27:1 (low ratio, LR), 5.01:1 (medium ratio, MR), and 10.38:1 (high ratio, HR). After 100 days of feeding, all goats were slaughtered. Dietary n-6:n-3 PUFA ratios had no effect (P > 0.05) on rumen pH and NH₃N concentration. Goats fed HR diet had lower (P < 0.05) propionate and total volatile fatty acids and higher (P < 0.05) butyrate compared with those fed the MR and LR diets. The proportion of C18:0 decreased (P < 0.05) as dietary n-6:n-3 PUFA ratios increased. The proportions of C18:1 trans-11, C18:2n-6, cis-9 trans-11 CLA, and C20:4n-6 were greater in the HR goats compared with the MR and LR goats. Lowering dietary n-6:n-3 PUFA ratios enhanced (P < 0.05) the proportion of C18:3n-3 and total n-3 PUFA in the rumen fluid of goats. The populations of R. albus and R. flavefaciens decreased (P < 0.05) as the n-6:n-3 PUFA ratios increased in diet. Diet had no effect (P > 0.05) on the ruminal populations of F. succinogenes, total bacteria, methanogens, total protozoa, Entiodinium, and Holotrich. The population of B. fibrisolvens was lower (P < 0.05) in the LR goats compared with the MR and HR goats. It was concluded that HR would increase the concentration of cis-9 trans-11 CLA and C18:1 trans-11 in the rumen. However, LR whould decrease the B. fibrisolvens population, which is involved in the BH process in the rumen. Further research is needed to evaluate the potential role and contribution of rumen microbiome in the metabolism of FA in the rumen.

Effect of supplementation with linseed or a blend of aromatic spices and time on feed on fatty acid composition, meat quality and consumer liking of meat from lambs fed dehydrated alfalfa or corn

Cross-bred lambs (n=72) were fed finishing diets using a factorial arrangement of treatments: BASAL DIET (alfalfa pellets or corn), SUPPLEMENT (none, linseed or aromatic spices), TIME ON FEED (41 or 83days). Carcass and meat quality traits, fatty acid composition, color stability and consumer liking were determined. Feeding alfalfa improved sensory ratings and fatty acid composition of lamb. However, corn or longer alfalfa feeding would be recommended if heavier and fatter carcasses are sought. Consumer liking and fatty acid composition of lamb were improved with addition of spices and linseed, respectively. But additional antioxidant strategies should be considered to delay meat color deterioration during storage if lambs are fed corn-linseed for 83days. Although alfalfa basal diet and linseed supplementation improved fatty acid composition, feeding the basal diets for at least 41days resulted in low n-3 fatty acid concentrations in muscle.

Influence of Diet and Postmortem Ageing on Oxidative Stability of Lipids, Myoglobin and Myofibrillar Proteins and Quality Attributes of Gluteus Medius Muscle in Goats

This study appraised the effects of dietary blend of 80% canola oil and 20% palm oil and postmortem ageing on oxidative stability, fatty acids and quality attributes of gluteus medius (GM) muscle in goats. Twenty-four Boer bucks were randomly allotted to diet supplemented with 0, 4 and 8% oil blend, fed for 100 days and slaughtered, and the GM muscle was subjected to a 7 d chill storage (4±1°C). Diet had no effect (P> 0.05) on the colour, drip loss, thiobarbituric acid-reactive substances (TBARS) value, free thiol, carbonyl, myoglobin and metmyoglobin contents, metmyoglobin reducing activity (MRA), antioxidant enzyme activities and abundance of myosin heavy chain (MHC) and actin in the GM muscle in goats. The meat from goats fed 4 and 8% oil blend had higher (P< 0.05) concentration of α and γ-tocopherol and abundance of troponin T compared with that from the control goats. The GM muscle from the oil-supplemented goats had lower (P< 0.05) concentration of C16:0 and greater (P< 0.05) concentration of C18:1n-9, C18:3n-3 and C20:5n-3 compared with that from the control goats. Nonetheless, diet did not affect (P< 0.05) the total fatty acid in the GM muscle in goats. Regardless of the diet, the free thiol and myoglobin contents, concentration of tocopherol and total carotenoids, MHC and MRA in the GM muscle decreased (P< 0.05) while carbonyl content, TBARS, drip loss and metmyoglobin content increased over storage. Dietary blend of 80% canola oil and 20% palm oil beneficially altered tissue lipids without hampering the oxidative stability of chevon.

Effects of dietary oil blend on fatty acid composition, oxidative stability and physicochemical properties of Longissimus thoracis et lumborum muscle in goats

This study examined the effects of dietary blend of 80% canola oil and 20% palm oil (BCPO) on the physicochemical properties, antioxidant status, oxidative stability and fatty acid composition of Longissimus thoracis et lumborum (LTL) muscle from goats during chill storage. Over a 14-week feeding trial, 24 Boer bucks were randomly assigned to and supplemented with diets containing 0, 4 or 8% BCPO on a dry matter basis, slaughtered and the LTL was subjected to a 7 day chill storage. Neither diet nor post mortem ageing influenced (P > 0.05) antioxidant enzyme activities, chemical composition and cholesterol. Diet had no effect on the carbonyl content, free thiol content, water-holding capacity, tenderness, pH and glycogen. Oil-supplemented goats had higher (P < 0.05) C18:1 trans-11, C18:3n-3 and C20:5n-3, carotenoid, tocopherol and redness, and lower thiobarbituric acid reactive substances values than the control goats. Post mortem ageing decreased (P < 0.05) shear force and oxidative stability of chevon. No significant (P > 0.05) changes were found in the proportion of individual fatty acids throughout storage. Total polyunsaturated fatty acids (PUFA) decreased while total saturated fatty acids increased as storage progressed. Dietary BCPO enhanced n-3 PUFA without compromising the quality attributes of chevon.