Lamb Meat Research Articles

Effects of supplementing a feedlot diet with microalgae (Chlorella vulgaris) on the performance, carcass traits and meat quality of lambs

This study evaluated the effect of different levels of fresh microalgae (Chlorella vulgaris) in a feedlot diet on the performance, carcass traits, and meat quality of lambs. Forty-five, four-month-old wether lambs were randomly assigned to one of three dietary treatments: 1) CONTROL, without algae; 2) MEDIUM, with 0.5 % dry matter (DM) algae; or 3) HIGH, with 1 % DM algae added to a basal diet consisting of barley hay and commercial feedlot pellets in a 41:59 ratio. The lambs were fed for 98 days and then slaughtered. Microalgae supplementation did not affect (P ≥ 0.09) growth performance, wool quality, rumen fermentation parameters, carcass weight, dressing percentage, or subcutaneous fat thickness of the lambs. However, microalgae supplementation at 0.5 % DM increased (P ≤ 0.05) the concentration of alpha-linolenic acid (ALA; C18:3n-3), arachidic acid (C20:0), and total omega-3 long-chain (n-3 LC) fatty acids in the longissimus lumborum et thoracis (LTL) muscle of lambs, compared to the CONTROL. Intramuscular fat (%) was similar between the CONTROL and the MEDIUM group (av. 3.65 %), but was lower (P = 0.044) in the HIGH group (3.1 %). Therefore, our results indicate that adding 0.5 % DM microalgae to lamb diets can increase the levels of alpha-linolenic acid and total n-3 LC PUFA in fresh lamb meat without affecting lamb performance or carcass characteristics.

Effects of dietary supplementation with Acaciamearnsii tannin extract on carcass characteristics and meat quality of lambs

BackgroundPlant extracts are used as possible methane mitigants and to replace antibiotic feed supplements previously used prophylactically to improve the adaptation of lambs in intensive feeding systems. This study investigated the effects of Acacia mearnsii tannin extract used as anti-methanogenic feed additives on carcass and meat quality of lambs.MethodsForty Dohne Merino lambs, with an initial mass between 23.90 kg and 37.40 kg, were first stratified according to their initial body weight and thereafter one of the eight lambs with similar body weight were randomly assigned to four treatment groups (n = 10 lambs/treatment). The lambs were fed ad libitum with a basal total mixed ration. Four experimental diets were formulated: TMR diet (control); TMR diet with Rumensin® at a dosage of 75 mg/kg of DM feed (Monensin; Positive control); TMR diet with raw condensed Acacia tannin at 20 g/kg of DM feed (Crude tannin); TMR with addition of encapsulated condensed Acacia tannin at 20 g/kg of DM feed (Encapsulated condensed tannins). The lambs were slaughtered at a live mass of about 50 kg after a 19 week trial period.ResultsDietary tannin additives did not affect the carcass composition or colour aspects of lamb meat. However, there were minor changes in fatty acid profiles, particularly in the intramuscular adipose tissue. The addition of encapsulated tannin extract resulted in a higher proportion of C18:2n6t (0.15% ± 0.03 vs. 0.19% ± 0.03; p < 0.05), C18.3n3 (0.24% ± 0.04 vs. 0.29% ± 0.04; p < 0.05), C22:6n3 (0.02 ± 0.01 vs. 0.05 ± 0.03; p < 0.05), in comparison to monensin. This improvement in fatty acid profiles is presumably beneficial for human health, but it could affect the sensory quality of meat.ConclusionOur results suggest that Acacia mearnsii tannin extracts can be included as anti-methanogenic feed additives in lamb diets without compromising product quality.

Effects of an essential oil blend rich in cinnamaldehyde and carvacrol on rumen biohydrogenation and fatty acid profile in the longissimus lumborum of growing lambs.

Essential oils extracted from cinnamon bark and oregano are rich in cinnamaldehyde and carvacrol and show potential for promoting animal performance. However, their impact on rumen biohydrogenation and the fatty acid composition of meat has not been reported. The hypothesis of this study was that a blend of essential oils rich in cinnamaldehyde and carvacrol would inhibit rumen biohydrogenation and promote the accumulation of polyunsaturated fatty acids (PUFAs) in lamb meat. The present study evaluated the effect of a blend essential oil (EO) rich in cinnamaldehyde and carvacrol on the nutrient digestibility, rumen biohydrogenation, growth performance, and fatty acid profile of the longissimus lumborum of lambs. Sixty male lambs with an average age of 84 ± 0.98 days and initial body mass of 25.4 ± 0.29 kg (mean ± standard deviation) were assigned randomly to four diets, and supplemented with 0 (EO0), 30 (EO30), 60 (EO60), and 120 (EO120) mg kg-1 dry matter of EO for 60 days. Although dry matter and neutral detergent fiber digestibility all showed a linear decrease (P ≤ 0.02) with increasing quantities of EO, final body mass and average daily gain increased linearly (P = 0.04), and average daily weight gain (ADG)/dry matter intake (DMI) tended to increase linearly (P = 0.07). Increasing EO supplementation resulted in a linear decrease in total volatile fatty acid concentration, acetate molar percentage, and acetate-to-propionate ratio (P ≤ 0.03), with the EO120 treatment being lower than the other EO treatments (P ≤ 0.05). Seven lambs from the EO120 treatment and seven lambs from the EO0 treatment were randomly slaughtered. It was observed that the proportions of C18:2n6c and PUFA in longissimus lumborum were higher in the EO120 treatment than the EO0 treatment (P ≤ 0.05). The relative abundance of Firmicutes in the rumen was decreased by the EO120 treatment in comparison with the EO0 treatment (P ≤ 0.05). Furthermore, the predicted relative abundances of genes encoding for conjugated linoleic acid reductase tended to decrease with the EO120 treatment (P = 0.06). We demonstrated that supplementation of the EO blend rich in cinnamaldehyde and carvacrol can enhance lamb growth performance and promote the deposition of desirable PUFAs in meat. © 2024 Society of Chemical Industry.

Orange (Citrus sinensis) essential oil inclusion in high-energy diets for feedlot lambs: productivity, eating behavior, carcass characteristics, rumen morphometry, and fatty acid profile of the meat

This study evaluated the effect of different orange essential oil (OEO) inclusion rates on live weight gain, eating behavior, carcass characteristics, morphology of the ruminal epithelium, and fatty acid profile in the meat of feedlot lambs. Forty uncastrated Dorper × Santa Inês ram lambs with an initial average body weight of 21.8 ± 4.7 kg and average age of 86 ± 15 days were allocated to one of five dietary treatments in a randomized complete block design. Dietary treatments consisted of a 90:10 concentrate-to-forage ratio total mixed ration supplemented as follows: 1. non-additive supplementation (Control), and 2. additive supplementation with 100, 500, and 1000 mg OEO/kg diet DM (OEO100, OEO500, and OEO1000) or with 25 mg sodium monensin/kg diet DM (MON). The feeding lasted 84 d. Supplementation with OEO increased linearly dry matter intake (DMI), growth rate and feed efficiency (FE). Because of the linear increases in growth rate and the efficiency of energy utilization of the diet, lambs receiving OEO exhibited a greater (increasing linear effect) hot carcass weight (HCW), Longissimus muscle area (LMA), subcutaneous fat thickness (SFT), and body wall thickness (BWT) than lambs fed with Control. Lambs fed MON had lower DMI, growth rate and FE than Control and OEO. Compared to Control and OEO supplemented, lambs that received MON showed lower HCW, LMA, SFT, and BWT. Lambs fed with MON had lower oocyst counts than lambs fed with all other treatments. Lambs fed with MON spent more time eating and ruminating, with higher chewing rates than lambs fed all other diets. Rumen morphometry was unaffected by dietary treatment. The OEO supplementation increased the sum of monounsaturated fatty acids, improved the human health promotion index (HP index), and reduced the thrombogenicity index in the meat relative to lambs fed the MON treatment. Under the conditions in which the experiment was conducted, the inclusion of up to 1000 g/kg diet DM in high-energy finishing diets promotes DMI and improved growth performance and FE. Improvements in the carcass (HCW, LMA, and BTF) with OEO supplementation were mainly due to improvements in growth rate rather than effects on gain composition. Based on growth performance and carcass characteristics, OEO was a superior feed additive to sodium monensin. The OEO supplementation has a discreet effect on the fatty acid profile of the meat, but it is sufficient to improve the HP index. These findings highlight its potential as an effective additive for enhancing lamb productivity.

Assessing the Impact of Sustainable Pasture Systems on Lamb Meat Quality

The global demand for sustainable lamb production is increasing due to the need for high-quality meat with minimal environmental impact, making the choice of feeding systems crucial. This study investigates the effects of supplemented pasture feeding during the last 60 days of rearing on the meat fatty acid profile, pH value, colour characteristics, and mineral composition of lambs, highlighting the benefits of such feeding systems. Ninety lambs (MIS sheep breed) were divided into three distinct feeding regimes: Group I (alfalfa and concentrate feeding), Group II (white clover [Trifolium repens] pasture with concentrate supplementation), and Group III (birds’ foot trefoil [Lotus corniculatus] pasture with concentrate supplementation). The results have shown that supplemented pasture feeding improves the fatty acid profile by increasing n-3 content and desirable fatty acids, while reducing the n-6/n-3 ratio and atherogenic index (p &lt; 0.05), particularly in lambs finished on an L. corniculatus diet. However, forage-supplemented feeding also reduces meat colour lightness and redness (p &lt; 0.05). On the other hand, it enhances the meat’s mineral profile, with higher calcium, selenium, and iron levels, especially in lambs fed L. corniculatus. These findings underscore the benefits of moderate grazing with supplemental concentrates in optimising lamb meat quality. Importantly, they also highlight the potential of forage legumes like T. repens and L. corniculatus to significantly enhance the nutritional profile of lamb meat, offering a promising outlook for the future of sustainable lamb production. Additionally, this research provides valuable insights that could guide the development of future agricultural practices, dietary guidelines, and environmental policies to advance sustainable and nutritious food systems.

Analysis of the physico-chemical characteristics and content of selected bioactive components in lamb meat, depending on the type of muscle and vacum-aging time

Analysis of the physico-chemical characteristics and content of selected bioactive components in lamb meat, depending on the type of muscle and vacum-aging time

Shortwave infrared hyperspectral imaging for the determination of pork adulteration in minced beef and lamb

Meat adulteration raises religious concerns and economic, quality, and safety issues. Therefore, ensuring that no unnecessary meat is added to the labeled primary meat is important. This study used shortwave hyperspectral imaging (SWIR HSI) working at 895–2504 nm to predict the level of pork adulteration in minced beef and lamb samples. Minced beef and lamb meat samples were adulterated with 2%–50% (w/w) minced pork. Unsupervised principal component analysis (PCA) was used to analyze and visualize the spectral data to determine their similarities. Spectral data were used to develop a partial least squares regression (PLSR) model to predict pork adulteration in minced beef and lamb. PLSR, with several spectral preprocessing methods, resulted in R2 0.97 and RMSE 2.47–2.55 for mixed pork and beef (Pork + Beef) model and R2 0.84–0.91 and RMSE 5.07–6.10 for mixed pork and lamb (Pork + Lamb) model. The developed PLSR model was then applied to each pixel in an image to obtain chemical maps to visualize the presence of pork in minced beef and lamb. This study demonstrated the potency of SWIR HSI to be applied in the sorting machine in meat industries to detect adulteration in meat.

Parkia platycephala pods in confined lamb diets: Fatty acid profile, ruminal biohydrogenation, and meat quality

This study was performed to evaluate the effects of replacing ground corn with Parkia platycephala pods (PPs) in lamb diets on the physicochemical characteristics of meat, the fatty acid profile in meat, and ruminal biohydrogenation (RBH). Twenty-eight castrated male lambs (20.05 ± 0.44 kg, 120 ± 10 days old) were distributed in a randomized block design constituting four treatments and seven replications. Four diets were formulated by replacing ground corn with PPs at increasing levels: 0 % PPs and 100 % ground corn (299.4 g/kg dry matter [DM]), 33 % substitution of ground corn (199.5 g/kg DM) with PPs (100.3 g/kg DM), 66 % substitution of ground corn (99.7 g/kg DM) with PPs (200.5 g/kg DM), and 100 % PPs (300.6 g/kg DM) and 0 % ground corn. The PPs resulted in a reduction in C18:1c9 intake; increased C12:0, C15:0, C18:1t9, C18:1t11, and C18:2n6; and reduced C18:0 in ruminal digesta, with a quadratic effect for C4:0 (P < 0.05). The RBH rate of C18:1c9 and C18:2n6 (P < 0.05) decreased as the PP levels in the diets increased. Regarding fatty acids in meat, there was a reduction in C16:1c9, C18:1c9, and cis-monounsaturated fatty acids and a quadratic effect for C14:1c9 and C18:2c9t11 (P < 0.05) as the PP levels in the diets increased. Levels of 66 % and 100 % PPs in the diets provided higher C18:2n6 in meat compared with the control diet (0 % PPs) and the diet containing 33 % PPs (P < 0.05). Under these experimental conditions, the replacement of corn with PPs in diets for lambs changed the fatty acid profile in the rumen digesta and lamb meat, promoting an increase in C18:1t11 in the rumen digesta. PPs can be used as an alternative ingredient in lamb feeding because they provide nutritional characteristics similar to those provided by corn.

Firewood as a tool to valorize meat: A sensory and instrumental approach to grilled veal, lamb, and pork meat

Two firewood species (beech and olive) were used for grilling three meat types (lamb, pork, and veal) to assess their influence on the sensorial properties of meat. A multimethod approach was adopted, including sensory evaluation with consumers and two analytical techniques to characterize the volatile fraction (Solid-Phase Micro-Extraction Gas Chromatography–Mass Spectrometry [SPME-GC/MS] and electronic nose [e-nose]). The sensory session included three pairwise preference tests (one for each type of meat), an overall liking test, a Rate-All-That-Apply test, and a questionnaire on the interest and perceived value of using sustainably certified firewood in food preparation. The firewood species significantly affected the perception of a few crucial attributes. In particular, olive wood increased the roasted meat flavor perception in lamb and veal, while beech wood increased the perceived intensity of a vegetable/herbaceous flavor in veal. No effect of firewood was observed on preference within each pair of meat samples. Lamb was the significantly most liked meat by consumers, followed by pork; veal was the least liked meat type. Positive and negative drivers of preference were discussed. 36 volatile organic compounds were identified from SPME-GC/MS in meats. Congruently with sensory data, the two veal samples showed a greater distance in terms of volatile composition. Relative distances among samples on maps obtained from SPME-GC/MS and the e-nose were similar. This multi-method approach innovatively showed the potential of using firewood as a ‘gastronomic’ tool to sensorially characterize and valorize cooked meat.

Fabrication and characterization of Karaya gum-based films reinforced with bacterial nanocellulose stabilized valerian root extract Pickering emulsion for lamb meat preservation

A novel biodegradable film was fabricated by incorporating bacterial nanocellulose stabilized valerian root extract (VRE) Pickering emulsion into karaya gum with better antioxidant and antibacterial properties for lamb meat preservation. The valerian root extract Pickering emulsion (VPE) exhibited 98 ± 1.84 % encapsulating efficiency and excellent physical stability with an average particle size of 274.6 nm. The incorporation of VPE-5 into the film matrix increased its elongation at break (EAB), and improved water resistance and barrier properties against oxygen, water vapor, and UV light. Moreover, the antioxidant and anti-bacterial properties against S.aerous and E. coli were also improved based on VPE-5 concentration. The SEM images showed a uniform distribution of VPE-5 while FTIR and XRD revealed its compatibility with karaya gum, which improved its thermal stability. The active films showed a significant preservative effect by reducing the pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and total viable count (TVC) value of lamb meat and maintained its texture and color during the storage period of 9 days at 4 °C. These results demonstrated the inclusion of VPE-5 into Karaya gum was a promising technique and offers a great potential application as a bioactive material in food packaging.

A strategy to increase lamb meat consumption from a relationship marketing perspective

A strategy to increase lamb meat consumption from a relationship marketing perspective

Technological and sensory characteristics in development of innovative symbiotic boneless dry-cured lamb meat snack

Novel shelf-stable and high-protein meat products that are affordable, convenient, and healthy are hot topic in current food innovation trends. To offer technological databases for developing new functional lamb meat products, this study aimed to evaluate the technological and sensory aspects of dry-cured lamb meat snacks incorporated with the probiotic culture Lactobacillus paracasei and the prebiotic lactulose. Four formulations were analyzed: control (without prebiotic or probiotic); PREB (with 2% lactulose); PROB (with 107 CFU/g of L. paracasei); and SYMB (with 2% lactulose and 107 CFU/g of L. paracasei). Fitted curves revealed that weight-loss behavior during snack ripening was not affected (P > 0.05) by treatments. Snack moisture, water activity, pH, titratable acidity, lipid oxidation, and residual nitrite were affected (P < 0.05) only by ripening time. The target probiotic strain stood out against competitive flora and was detected at 107 CFU/g in the snack-supplemented formulations (PROB and SYMB). In snacks supplemented with prebiotics (PREB and SYMB), the lactulose content was maintained at 2.17%. Significant differences were not observed in the chemical composition, texture profiles, and CIE color indices between the proposed functional snacks and the control. In addition to texture, flavor, and overall impression evaluation, only color attributes were positively impacted (P < 0.05) in the acceptance and multiple comparison tests against the control. The proposed formulation and bench process parameters produced potential nutritionally and sensory-appreciated, microbiologically stable, and safe (multi-hurdle perspective) functional high-protein restructured lamb snacks.

Association of CYP2A6 gene related to the characteristic carcass, commercial cuts, quality of meat and cholesterol of lamb meat

Association of CYP2A6 gene related to the characteristic carcass, commercial cuts, quality of meat and cholesterol of lamb meat

Ammonia/pH super-sensitive colorimetric labels based on gellan gum, sodium carboxymethyl cellulose, and dyes for monitoring freshness of lamb meat

This study aimed to develop an ammonia and pH super-sensitive label by incorporating methyl red and bromothymol blue (MR-BTB, MB) into gellan gum/sodium carboxymethyl cellulose (GG/CMC-Na, GC). Furthermore, E-nose as an auxiliary tool combined with the labels to monitor meat freshness. Results showed that MB had more color change than pure MR or BTB, and the detection limit of ammonia about the MR-BTB (1:2) group was only 2.82 ppm. The addition of MB significantly increased tensile strength, moisture content, and water solubility, but decreased elongation at break and transmittance of the GC label (p < 0.05). The result of FTIR and SEM indicated the formation of hydrogen bonds and well compatibility between MB and GC. Furthermore, the color of the GC-10.0MB label was constantly obviously changing during meat storage, indicating that the GC-10.0MB label had great potential for monitoring the freshness of the lamb meat. A high correlation was found between ΔE of GC-10.0MB label and TVB-N (R2 = 0.9092) and pH (R2 = 0.9114) of meat. Interestingly, the high correlation between ΔE of GC-10.0 MB label and the response value of S2 (R2 = 0.7531), S6 (R2 = 0.9921), and S7 sensor (R2 = 0.8325) of E-nose was also found.

Polymorphism of BGN gene (g.77807325 G&gt;C) and its association with fatty acid and carcass characteristics of Indonesian meat lamb

Fatty acid content and carcass characteristics are two meat quality traits consumers choose to ob tain healthy and high-quality lamb. Genetic improvement of fatty acid content and carcass characteris tics in sheep is important to increase the public appeal of lamb meat. The Biglycan gene (BGN) is a gene that functions to regulate the growth and maintenance of connective tissues, such as bone and cartilage. This study examined the polymorphism of the BGN gene to get a deeper understanding of the correlation between fatty acid content and carcass traits in Indonesian sheep. The PCR-RFLP ap proach was used to detect polymorphism in the BGN gene in meat samples obtained from the longissi mus dorsi region of 115 rams aged between 10 and 12 months. The General Linear Model (GLM) was used test to analyze genotyping through association studies between genotypes and phenotypic attrib utes. The results indicated that the carcass' fatty acid composition, including tridecanoic acid (C13:0), arachidonic acid (C20:4n-6), and polyunsaturated fatty acids (PUFA), as well as the BGN gene with SNP point g. 77807325 G&gt;C (GG and CC genotypes), were significantly (P&lt;0.05) related to these traits. Genotype GG was more associated with carcass percentage traits than other genotypes, whereas genotype CC was best associated with carcass length traits. The BGN gene with SNP point g. 77807325 G&gt;C can be a potential genetic marker for selecting fatty acid (tridecanoic acid C13:0), pol yunsaturated fatty acid (PUFA), arachidonic acid), carcass percentage, and carcass length in sheep meat in Indonesia.

Effectiveness of machine learning algorithms as a tool to meat traceability system. A case study to classify Spanish Mediterranean lamb carcasses

Establishing the traceability of meat products has been a major focus of food science in recent decades. In this context, recent advances in food nutritional biomarker identification and improvements in statistical technology have allowed for more accurate identification and classification of food products. Moreover, artificial intelligence has now provided a new opportunity for optimizing existing methods to identify animal products. This study presents a comparative analysis of the effectiveness of different machine learning algorithms based on raw data from analyses of organoleptic, sensory and nutritional meat traits to differentiate categories of commercial lamb from an indigenous Spanish breed (Mallorquina breed) obtained from the following production systems: suckling lambs; light lambs from grazing; and light lambs from grazing supplemented with grain. Six machine learning algorithms were evaluated: Artificial Neural Network (ANN), Decision Tree, K-Nearest Neighbours (KNN), Naive Bayes, Multinomial Logistic Regression, and Support Vector Machine (SVM). For each algorithm, we tested three datasets, namely organoleptic traits and sensorial traits (CIELAB colour, water holding capacity, Warner-Bratzler shear force, volatile compounds and trained tasters), and nutritional traits (proximate composition and fatty acid profile). We also tested a combination of all three datasets. All the data were combined into a dataset with 144 variables resulting from the meat characterization, which included 11,232 event records. The ANN algorithm stood out for its high score with each of the three datasets used. In fact, we obtained an overall accuracy of 0.88, 0.83, and 0.88 for the organoleptic-sensory, nutritional, and combined datasets, respectively. The effectiveness of using the SVM algorithm to assign categories of lambs according to its production system performed better with nutritional traits and the full characterization, with performances equal to those obtained with ANN. The KNN algorithm showed the worst performance, with overall accuracies of 0.54 or lower for each of the datasets used. The results of this study demonstrate that machine learning is a useful tool for classifying commercial lamb carcasses. In fact, the ANN and SVM algorithms could be proposed as tools for differentiating categories of lamb production based on the organoleptic, sensory and nutritional characteristics of Mediterranean light lambs' meat. However, in order to improve the traceability methods of lamb meat production systems as a guarantee for consumers and to improve the learning processes used by these algorithms, more studies along these lines with other lamb breeds are required.

The carcass characteristics and quality of meat from lambs grazing perennial wheat with different companion legumes (clover, serradella, lucerne) or a mineral supplement

This study compared carcasses as well as the quality and mineral concentration of meat from lambs extensively grazing perennial wheat with clover (PW + C), serradella (PW + S), lucerne (PW + L), or a mineral salt supplement (PW + Min). A split-plot design was used, wherein 3 crossbred ewe lambs (n = 72 in total) (sub-plots) grazed each of 4 forage types (plots), that were replicated across 6 locations (blocks). The feeding study concluded after 96 d, when all the lambs were slaughtered. The left longissimus lumborum muscles (LL) were collected and wet aged for either 5 or 56 d post-mortem. Lambs grazing PW + Min were found to produce carcasses with lower dressing percentage values to those grazing the other forage types (P = 0.037). The LL of lambs grazing PW + L had the lowest crude protein values (P = 0.015). Forage type by ageing period interactions did not affect meat quality. The 56 d ageing period resulted in higher purge loss (P < 0.001) and TVB-N values (P < 0.001) and a decline in shear force (P < 0.001) compared to the 5 d ageing period. The other carcass and meat quality parameters were not affected by forage type; including hot carcass weight, pH decline parameters, eye muscle area, cooking loss, intramuscular fat, sarcomere length, colour stability, and concentrations of calcium, iron, magnesium, sodium, and zinc in the LL. These findings confirm that perennial cereal production systems, that include legume forages with contrasting protein, energy, and micronutrient profiles, can deliver comparable lamb carcasses and meat quality.

Effect of dietary inclusion of urea encapsulated in low-trans vegetable fat microspheres on fatty acids intake, carcass traits, quality, and fatty acid composition of lamb meat

This study evaluated the effect of including slow-release urea (SRU) coated from the low-trans vegetable fat (LTFV) microspheres in the diet of lambs on fatty acids intake, carcass traits, meat quality, and fatty acid composition of meat. Thirty-two non-castrated Santa Inês lambs (17.98 ± 2.01 kg of initial weight) were used in a randomized complete block design. Experimental treatments included a control which contained 5 g/kg urea (U0.5%) and three other treatments in which SRU (60% LTFV and 40% urea) was incorporated at 1.25% (SRU1.25%); 2% (SRU2.0%) and 3% (SRU3.0%) of total diet dry matter (DM). The inclusion of SRU in lamb diets increased linearly (P < 0.05) the intake of ether extract, metabolizable energy, and fatty acids. Carcass traits and physical-chemical composition of the Longissimus muscle were not changed by protected urea addition in lamb diet (P > 0.05). The addition of the protected urea in lamb diet linearly increased proportions of CLA and the 18:1 isomer (cis-12, cis-15, and cis-16) compared to U0.5%. There was a linear increase in branched-chain fatty acid (BCFA) content (P = 0.048) in Longissimus muscle due SRU inclusion. There were a quadratic increases for the sums of trans-MUFA (P = 0.003) and n-6 PUFA (P = 0.046) and total PUFA (P = 0.037) as SRU was added to lambs diet. Adding urea coated into low-trans vegetable fat microspheres increased the lamb intake of most FA and energy dietary, however, without affecting carcass traits and meat physicochemical composition. The inclusion of protected urea (SRU) in the lamb diet quadratically increases trans-MUFA, n-6 PUFA, and total PUFA concentrations in meat, and lambs fed with SRU at level 1.25% in DM total diet presented greater CLA and trans-MUFA concentrations compared free urea (U0.5%), which is beneficial from the point of view of the lipid quality of the meat and its relationship with consumer health.

Exercise influences fatty acids in the longissimus dorsi muscle of Sunit lambs and improves dressing percentage by affecting digestion, absorption, and lipid metabolism

The transition from grazing to captive rearing resulted in a significant decline in meat quality. To enhance the quality of meat from captive sheep, we examined the impact of exercise on Sunit lambs. The lambs, with similar body weight and aged 3 months underwent a 90-day period of thought-driven exercise. At the end of the exercise period, we collected colonic contents, epithelial tissues, and the longissimus dorsi muscle, and recorded slaughter performance. Exercise was found to have a significant impact on the content of short-chain fatty acids in the colon. Additionally, it generally reduced the mRNA expression of fatty acid absorption transporter genes in the colonic epithelium and lipid metabolism-related genes in the longissimus dorsi muscle. Furthermore, exercise significantly affected the content of fatty acids in the longissimus dorsi muscle of Sunit lambs, and increased its dressing percentage. Exercise influences the composition of fatty acids of the longissimus dorsi muscle and improves dressing percentage by affecting the digestion, absorption, and metabolism of lipids in Sunit lambs. This could be profitable for the livestock industry, and could alter the nutrition and flavor of lamb meat.

Lamb meat colour is minimally affected under reduced oxygen concentration in modified atmosphere packaging

This study investigated how modified atmosphere packaging (MAP) with lower oxygen concentrations affects meat surface redness compared to standard 80% oxygen MAP for sheepmeat. Colour measuring instruments assessed redness (oxymyoglobin to metmyoglobin ratio and a*) in M. longissimus lumborum (loin) and M. semimembranosus (topside) from 50 Merino lambs. After 5 or 20 days of vacuum storage, meat samples were re-packaged into one of five MAP treatments (0, 20, 40, 60, or 80% oxygen), and colour was measured after 2, 6, or 10 days of retail display. Decreasing oxygen from 80% to 40% showed no negative impact on loin redness during retail display. Topside samples under 40% oxygen exhibited lower oxy/met values than 80% oxygen MAP at 2 and 6 days, with no difference after 10 days. This finding highlights the potential to reduce MAP oxygen content to 40% without compromising surface redness, potentially mitigating adverse effects on eating quality.