Dietary tannins improve lamb meat colour stability

Effects of intermittent cold stimulation on growth performance, meat quality, antioxidant capacity and liver lipid metabolism in broiler chickens

Intermittent cold stimulation (ICS) enhances broilers' resistance to cold stress. Nonetheless, further research is needed to investigate the underlying mechanisms that enhance cold stress resistance. A total of 160 one-day-old male Ross 308 broilers were randomly divided into 2 groups (CC and CS5), with the CC group managing temperature according to the standard for broiler growth stages, while the CS5 group were subjected to cold stimulation at a temperature 3℃ lower than the CC group for 5 h, every 2 d from 15 to 35 d. Sampling was conducted at 36 d (36D), 50 d (50D) and after acute cold stress for 24 h (Y24). First, we examined the effects of ICS on broiler growth performance, meat quality, antioxidant capacity, and lipid metabolism. The results demonstrated that ICS enhanced the performance of broilers to a certain degree. Specifically, the average weight gain in the CS5 group was significantly higher than that of the CC group, and the feed conversion ratio significantly decreased compared to CC at 4 W and 6 W (P ≤ 0.05). Compared with the CC group, cold stimulation significantly reduced drip loss, shearing force, and yellowness (a* value) of chicken meat, while significantly increased redness (b* value) (P ≤ 0.05). At Y24, the levels of T-AOC and GSH-PX in the serum of the CS5 group were significantly higher than those of the CC group, while the level of MDA was significantly lower (P ≤ 0.05). The content of TG, FFA, and VLDL in the serum of the CS5 group was significantly elevated, whereas the level of TC and HDL was significantly lower (P ≤ 0.05). In addition, we further explored whether AMPK-mTOR pathway is involved in the regulation of changes in lipid metabolism and the possible regulatory mechanisms downstream of the signaling pathway. The results showed that ICS significantly upregulated the expression levels of AMPK mRNA and protein in the liver of the CS5 group at 36D and Y24, while significantly down-regulating mTOR (P ≤ 0.05). Compared with the CC group, ICS significantly down-regulated the mRNA expression levels of lipid synthesis and endoplasmic reticulum stress-related genes (SREBP1c, FAS, SCD, ACC, GRP78 and PERK) at 36D and Y24, while significantly up-regulating the mRNA expression levels of lipid decomposition and autophagy-related genes (PPAR and LC3) (P ≤ 0.05). In addition, at Y24, the protein expression levels of endoplasmic reticulum stress-related genes (GRP78) in the CS5 group were significantly lower, while autophagy-related genes (LC3 and ATG7) were significantly higher (P ≤ 0.05). ICS can affect meat quality and lipid metabolism in broilers, and when broilers are subjected to acute cold stress, broilers trained with cold stimulation have stronger lipid metabolism capacity.

Supplementation of chestnut tannins in diets can improve meat quality and antioxidative capability in Hu lambs

Chestnut tannins (CNT), as a source of hydrolyzable tannins, positively affect the antioxidant status of livestock. In the current study, 90 male Hu lambs were used to investigate the effect of dietary CNT intake on growth performance, nutrient digestibility, meat quality and oxidative stability, rumen microbial, and the transcriptomes of muscle and liver. A completely randomized design with three CNT intake levels (0, 0.3%, and 0.6%) was used. Rumen microbial and nutrient digestibility were not significantly altered by CNT intake. Diets with 0.3% CNT intake significantly reduced the shear force, yellowness at 24 h, and C20:2 polyunsaturated fatty acids of lamb meat and malondialdehyde in serum and longissimus thoracis (LT) muscle. Meanwhile, the 0.3% CNT diet significantly increased average daily gain during the 1- 21 days and 64- 90 days, dry matter intake during the 1- 21 days, the slaughter weight, and liver index of lambs. The 0.3% CNT diet significantly increased C26:0 saturated fatty acids, total antioxidant capacity, glutathione peroxidase, superoxide dismutase, and catalase in LT muscle. The meat shelf life of 0.3% CNT and 0.6% CNT groups was prolonged by 8.7 h and 5.4 h, respectively. Transcriptomic analysis revealed that CNT supplementation can induce the expression of antioxidant enzyme gene (CAT, SOD1), and the differentially expressed genes were mainly involved in antioxidant activity, transferase activity, and adenosine triphosphate binding. These results suggest that 0.3% CNT intake can relieve the oxidative stress of lambs, and improve the stability of meat color and meat tenderness, due to the enhanced antioxidative capacity.

Growth Performance, Rumen Fermentation, In Vivo Digestibility, and Meat Quality of Pelibuey Lambs Fed a Diet with Ensiled Coffee Pulp

Coffee pulp has been included in ruminant diets; but until now, little has been known about how the addition of ensiled coffee pulp (ECP) affects the growth performance of lambs. This study explores the diet's antioxidant capacity, tannins, and caffeine concentration and its effect on water intake, growth performance, rumen variables, in vivo digestibility, nitrogen balance, and carcass and meat characteristics of lambs fed ECP. Thirty-six male Pelibuey lambs were distributed randomly to one of three treatments (n = 12): without ECP0; diet with 10% ECP10, and diet with 20% ECP20. The diets' antioxidant capacity, tannins, and caffeine concentration were similar (p > 0.05) for all treatments. The diets' antioxidant compounds and the blood serum's antioxidant capacity were affected (p < 0.05). Dry matter and water intake, body-weight gain, and feed conversion were not significant (p > 0.05). No differences (p > 0.05) were found in the rumen variables or the nitrogen balance. However, the in vivo digestibility of crude protein was affected (p < 0.05). Carcass and meat quality were not affected (p > 0.05) by the inclusion of ECP, except temperature and redness (a*) at seven days of storage, respectively. Including up to 20% of ECP in the diet of lambs did not affect the growth performance, rumen variables, or nitrogen balance; however, the antioxidant compounds of the diets, the antioxidant capacity in blood serum, and the in vivo digestibility of crude protein were different. There was an increase in the redness (a*) and lower temperature in the Longissimus dorsi muscle, keeping lightness (L*), yellowness (b*), water-holding capacity, and texture at seven storage days.

Effect of age and diet on carcass and meat quality in ewes

This study elucidated the effect of age and diet on carcass characteristics and meat quality parameters of Rambouillet ewes. Forty ewes (n = 20 yearling ewes and n = 20 cull ewes) were fed with alfalfa hay (AH) or a 100 % concentrate diet (CD). Treatments were: a) 10 cull ewes were fed only with AH, b) 10 yearling ewes were fed only with AH, c) 10 cull ewes were fed with CD, d) 10 yearling ewes were fed with CD. Productive performance, carcass and meat quality were analyzed. Animals had ten days for adaptation and 35 days were used to collect data. Dry matter intake was greater (P < 0.05) for CD. Feed conversion rates were not affected by treatments. The pH at 45 min and 24 h, carcass length, leg length, leg width, thorax width, and thorax perimeter were not affected by treatments. Hot carcass weight was heavier (P < 0.05) in cull ewes, cold carcass weight was increased (P < 0.05) with CD. Carcass yield (CY) was heavier in CD (P < 0.05). Cull ewes had greater (P < 0.05) lean CIELAB L*, a*, b*, c*, and h* values compared to yearling ewes. The color changes increased with age at five days (P < 0.05), but a decrease (P < 0.05) with diet was observed at ten days. Cathepsins B, B + L, and Lowry protein content were not affected by treatments. In conclusion, feeding cull ewes with concentrate diets may enhance body weight gain and carcass yield compared to a diet based on 100 % alfalfa hay.

In-depth characterization of the sarcoplasmic muscle proteome changes in lambs fed with hazelnut skin by-products: Relationships with meat color

This study investigated the effect of agro-industrial hazelnut skin by-products supplementation on lamb meat color variation and the changes in the sarcoplasmic muscle proteome during post-mortem storage (0, 4 and 7 days). Gel-based proteomics and bioinformatics approaches were applied to better understand the potential role of feeding strategies in modulating the mechanisms underpinning meat discoloration and post-mortem changes during storage. Therefore, twenty-two Valle del Belice male lambs were randomly assigned to two dietary treatments: control (C), lambs fed with maize-barley diet, and hazelnut skin (H), lambs fed hazelnut skin by-product as maize partial replacer in the concentrate diet. Hazelnut dietary treatment led to better lamb meat color stability as evidenced by the lowest decrease in redness and saturation index values. Proteomics and bioinformatics results revealed changes in the abundance of 41 proteoforms, which were mainly involved in glycolytic processes, responses to oxidative stress, and immune and endocrine system. The proteins allowed revealing interconnected pathways to be behind meat color variation as a consequence of using hazelnut skin by-products to sustainable feed lamb. The proteins can be used as potential predictors of lamb meat color variation. Accordingly, the regression equations developed in this paper revealed triosephosphate isomerase (TPI1) as a reliable candidate biomarker of color stability in lamb meat. SIGNIFICANCE: The use of agro-industrial by-products in animal feeding can be a potential sustainable strategy to reduce the environmental impacts of the food production chain and consequently improve animal welfare and product quality. The inclusion of hazelnut skin by-products in the animal's diet, due to the high concentration of polyphenols, represents an effective strategy to improve the oxidative stability of meat, with significant implications on color. The use of proteomics combined with bioinformatics on the sarcoplasmic proteome is a powerful approach to decipher the underlying mechanism. Accordingly, this approach allowed in this trial a deeper understanding of the molecular mechanisms involved in the post-mortem processes through the discovery of several biological pathways linked with lamb meat color variation. Glycolysis, followed by responses to oxidative stress, and other proteins involved in the immune and endocrine system were found as the major interconnected pathways that could act as potential predictors of lamb meat color stability. Candidate proteins biomarkers were further revealed in this study to be related with multiple meat color traits.

Colour Stability, Fatty Acid Profile, and Lipid Oxidation in Meat Stored in Modified Atmosphere Packaging from Light Lambs Fed with Concentrate with Carob Pulp (Ceratonia siliqua L.)

There is a growing interest in using by-products rich in polyphenols, such as carob pulp (Cp, Ceratonia siliqua L.), as a dietary source of antioxidants for animals. This study assesses the effects of including Cp in lambs' diet and meat display time (0, 7, 9, and 11 days) in modified atmosphere packaging on meat colour, fatty acid (FA) composition, tocopherol levels, and lipid oxidation values in the Semimembranosus muscle of 40 light lambs. The lambs were fed with concentrates supplemented with increasing Cp levels (0, 150, and 300 g/kg) for 45 days before slaughter. Metmyoglobin (MMb) and malondialdehyde (MDA) contents increased linearly with display time (p < 0.05), regardless of diet (p > 0.05). At 11 days of display, MMb (28 ± 0.8%) and MDA (0.6 ± 0.1 mg MDA/kg of meat) contents remained within the acceptable limits. The α-tocopherol content was lower in the 30% Cp group and meat (p < 0.05). Total saturated and monounsaturated FA contents (934 ± 64 and 823 ± 65 mg/100 g of meat, respectively) did not differ significantly among the groups. However, the meat from lambs fed with 30% Cp showed reduced levels of branched-chain FAs, while polyunsaturated FAs increased (p < 0.05) compared to the control lambs. The inclusion of Cp in the lamb's diet, up to 30%, did not lead to meat deterioration and improved certain quality parameters, including a healthier FA profile. These findings highlight Cp's potential as an alternative antioxidant source in animal diets.

Fatty acid and oxidative shelf-life profiles of meat from lambs fed finisher diets containing Acacia mearnsii leaf-meal

Five diets containing Acacia mearnsii leaf-meal (AMLM; 0, 50, 100, 150 and 200 g/kg DM) substituted for Triticum aestivum bran were fed to lambs for 42 days. The effect of diet and retail display period on meat fatty acid (FA) composition (day 1); colour, antioxidant activity, myoglobin and lipid oxidation (day 1, 3, 5, 7 and 9); protein oxidation (1, 3 and 7 d) and instrumental tenderness (day 1, 5 and 10) were evaluated. Dietary AMLM linearly decreased (P ≤ 0.05) individual (14:0, 16:0, 18:0) and total saturated FA and increased (P ≤ 0.05) trans(t)-monounsaturated FA (MUFA) mainly t10/t11-18:1, individual and total conjugated linoleic acids, n-3 and n-6 polyunsaturated FA (PUFA) contents. The contents of cis(c)-MUFA, mainly c9-18:1, exhibited a quadratic response reaching a minimum at 50 g/kg AMLM (P ≤ 0.05). Meat antioxidant on day 9 was higher (P ≤ 0.05) for diets containing ≥100 g/kg DM AMLM compared to the other diet × retail display period interactions. Relative to the other interactions, meat redness values were lowest on day 7 and 9 for AMLM diets containing ≥150 g/kg DM (P ≤ 0.05). Dietary addition of AMLM increased (P ≤ 0.05) meat lightness and oxymyoglobin, and reduced (P ≤ 0.05) TBARS and instrumental tenderness values. However, oxymyoglobin values declined (P ≤ 0.05) over the retail display period, while lightness, metmyoglobin, TBARS and carbonyls increased (P ≤ 0.05). Results indicate that AMLM up to 200 g/kg DM in lamb finisher diets, improves meat fatty acid composition, tenderness, and lipid shelf-life.

Dietary Grape Pomace Supplementation in Lambs Affects the Meat Fatty Acid Composition, Volatile Profiles and Oxidative Stability

The aim of this study was to evaluate the effects of supplementing grape pomace (GP) in lambs’ diets. A total of 30 lambs homogeneous for body weight (13.1 ± 2.1 kg) and age (25–30 days) were randomly allocated into two groups. The control group (CTR) received a standard diet for 45 days, while in the same period the experimental group (GP+) was fed with a diet containing 10% GP on a dry matter (DM) basis. The meat samples from the two groups showed no significant differences in drip loss, cooking loss, meat color and total lipid amount. However, the experimental feeding strategy influenced the meat fatty acid composition, with an increase in the relative percentages of stearic, vaccenic and rumenic acids. In particular, the increase in rumenic acids is associated with several health benefits attributed to its high bioactive properties. In cooked meat samples stored for 5 days at 4 °C, the dietary GP supplementation induced an increase in nonanal and 1-octen-3-ol and a significant reduction of hexanal, an indicator of oxidation; this improved resistance to oxidation in the GP+ samples and was also confirmed by the thiobarbituric acid reactive species (TBARS) test. In summary, the present study showed that the dietary GP supplementation was effective in improving the fatty acid composition and the oxidative stability of lamb meat. The use and valorization of the GP as a matrix of interest for zootechnical nutrition can, therefore, represent a suitable strategy for improving the qualitative aspects of animal production.

Effects of supplementing sweet sorghum with grapeseeds on carcass parameters, and meat quality, amino acid, and fatty acid composition of lambs

OBJECTIVE

Sweet sorghum is an important forage crop for ruminants, especially in low rainfall areas. Grapeseeds are an abundant by-product of wine-making and contain bioactive substances that can improve the antioxidant capacity of meat. We examined the effect of sweet sorghum forage with supplementary grapeseeds on carcass and meat quality in lambs.

METHODS

Twenty-eight Small-tailed Han lambs (body weight = 19.1±1.20 kg), aged 3 to 4 months, were penned, and fed individually. The lambs were divided into four groups (n = 7 each) and were offered one of four diets: i) sweet sorghum silage; ii) sweet sorghum silage + grapeseeds; iii) sweet sorghum hay; and iv) sweet sorghum hay + grapeseeds. The grapeseeds were added to the concentrate at 6% DM and the diets were fed for 100 d.

RESULTS

Sweet sorghum silage tended (p = 0.068) to increase hot carcass weight, while grapeseeds tended (p = 0.081) to decrease dressing percentage without affecting other carcass parameters. Lambs consuming supplementary grapeseeds increased (p<0.05) meat redness and tended to decrease (p = 0.075) concentration of methionine in meat. Lambs consuming sweet sorghum silage increased (p<0.001) water content of the meat and had a lower (p<0.05) concentration of n-6 polyunsaturated fatty acids (PUFA) and n-6:n-3 PUFA ratio than lambs consuming sweet sorghum hay. Saturated fatty acids content in meat was lowest (p<0.05) in lambs consuming sweet sorghum silage with grapeseeds. Lambs with supplementary grapeseeds tended (p<0.10) to increase eicosapentaenoic acid and docosahexaenoic acid and have a lower thrombogenic index than lambs not consuming grapeseeds.

CONCLUSION

It was concluded that sweet sorghum with supplementary grapeseeds fed to lambs; i) improved the color of the meat to be more appetizing to the consumer; ii) tended to improve the fatty acids composition of the meat; and iii) lowered thrombogenic index of the meat.

Meat quality, metabolic profile and antioxidant status of lambs fed on seedless grape pomace (Vitis vinifera L.)

This study was aiming to research the effect of the seedless grape pomace (GP) added to feed mixture on meat quality, metabolic profile, and antioxidant status of Merinolandschaf lambs. The 90 days old lambs in the control group (C, n=10) were fed feed mixture without GP while in experimental groups were fed with 10% (GP10, n=10) or 20% (GP20, n=10) of GP in feed mixture for 30 days. There was a significant increase in L*, a* values and hue angle as well as a decrease in b* values of lamb carcasses in GP10 and GP20 compared to C group. When lambs were fed GP glucose concentrations decreased, while non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHB) increased on the 30th day in GP10 and GP20 compared with C group. A significant increase in SOD activity on day 30 and GPx activity on day 15 in lambs’ blood of GP10 and GP20 compared with C group was determined. Also, an increase in DPPH in lamb GP10 and GP20 compared with C was determined. The obtained results of the meat quality, metabolic profile and antioxidant status parameters of lamb meat showed that the use of 10% GP in the diet is justified, while 20% of GP was questionable.

Effect of hazelnut skin by-product supplementation in lambs' diets: Implications on plasma and muscle proteomes and first insights on the underlying mechanisms

This study aimed to evaluate the effect of hazelnut skin by-product supplementation on lamb meat quality characteristics and plasma and muscle proteomes. Twenty-two Valle del Belice male lambs were divided into two experimental groups: control (C), fed a maize-barley diet and hazelnut (H), fed hazelnut skin by-product as maize partial replacer in the concentrate diet. The meat of lambs fed hazelnut skin showed greater values of lightness, redness, yellowness, and chroma color parameters together with the highest myofibril fragmentation index. Two-dimensional electrophoresis and mass spectrometry applied on plasma proteome identified 20 protein spots corresponding to 18 unique gene names to be differently expressed due to hazelnut skin by-product substitution. For the early post-mortem muscle, 23 protein spots (42 unique gene names) were significantly up-regulated due to hazelnut skin by-product supplementation. Four proteins these being APOA1, PHB, ACTG1 and ALB, were found to be common to the two proteomes suggesting that these proteins could be candidate biomarkers to monitor in vita and post-mortem lamb meat quality traits. This study evidenced the main mechanisms involved in the supplementation of hazelnut skin by-product in lambs' diet and confirmed the possibility of using plasma proteome as a non-invasive way to predict lamb meat quality. SIGNIFICANCE: Maximizing the use of agro-industrial by-products as replacers of traditional feedstuff for improving animal products is one of the important challenges to preserving natural resources and guaranteeing environmental sustainability. Hazelnut (Corylus avellana L.) skin, obtained as a results of hazelnut roasting, represents a valuable by-products due to its high content in unsaturated fatty acids, tannins, and vitamins. Thus, including hazelnut skin by-product in small ruminant nutrition could reduce the costs of animal feedings for farmers as well as improve meat nutritional and sensorial characteristics. Additionally, monitoring the meat quality characteristics with fast, accurate, and non-invasive tools to find, before slaughter, animals with desired quality characteristics is of growing interest in the last years. In this regard, the objectives of this study were to assess i) the effect of hazelnut skin supplementation on lamb meat quality characteristics and plasma and muscle proteomes, and ii) whether analyzing plasma proteome by using a gel-based proteomic approach could effectively offer a more readily available option for determining lamb meat quality. Taken together, the proteomic approach applied to plasma and muscle proteomes, allowed us to reveal the pathways and the potential candidate plasma biomarkers to predict lamb meat production in the pre-slaughter phase.

Adding of Allium mongolicum regel extracts to lamb feedlot diets influences 4-alkyl-branched fatty acids deposition and the meat quality during storage

The present study aimed to investigate the effect of dietary supplementation with Allium mongolicum Regel extracts on the 4-alkyl-branched fatty acid deposition and meat quality during storage. Small-tailed Han sheep were divided into four groups (n = 15) and fed for 75 days with a basal diet (CK), CK supplemented with A. mongolicum Regel powder (AMR), A. mongolicum Regel water-soluble extract (AWE), or A. mongolicum Regel ethanol-soluble extract (AFE). The results revealed that both AMR and AWE diets decreased the 4-alkyl-branched fatty acids content in longissimus thoracis. Diet × storage time interactions were observed for acid value (AV), peroxidase (POx), glutathione peroxidase (GSH-Px), and total volatile base nitrogen (TVB-N). Patterns of change for AV, POx, and GSH-Px over time leading to the interactions were not readily apparent and changes were more governed by main effects. Dietary supplementation with AMR and AWE increased the total antioxidant capacity, total superoxide dismutase, and inhibited total bacteria counts compared to those in the CK lambs. The AWE diet also decreased the yellowness and hue angle. Overall, A. mongolicum Regel and its extracts could be used as a source of natural bioactive compounds in the lambs' diet to extend the storage time of their meat.

The effect of varying levels of purified condensed tannins on performance, blood profile, meat quality and methane emission in male Bapedi sheep fed grass hay and pellet-based diet

This study determined the effect of purified condensed tannin inclusion levels in a diet on production, haematological indices, blood biochemical components, meat quality and methane emission by yearling indigenous male Bapedi sheep on a grass hay and sheep pellet-based diet in a 28-day trial. The diets contained similar (P > 0.05) nutrients but with different (P < 0.05) purified condensed tannin supplementation levels. A complete randomized design was used. Twenty-four yearling male Bapedi sheep were assigned to four dietary treatments having different purified condensed tannin levels of 0 (GH₈₀P₂₀PCT₀), 30 (GH₈₀P₂₀PCT₃₀), 40 (GH₈₀P₂₀PCT₄₀) and 50 (GH₈₀P₂₀PCT₅₀) g/kg DM. A quadratic type of equation was also used to determine condensed tannin supplementation levels for optimal performance and methane emission reduction by sheep. Supplementing diets with purified condensed tannins did not affect (P > 0.05) diet intake, digestibility and live weight gain of male Bapedi sheep. Supplementing diets with purified condensed tannins did not affect (P > 0.05) blood components of male Bapedi sheep. Inclusion of condensed tannins in the diets did not affect (P > 0.05) Bapedi sheep meat pH and sensory attributes. However, supplementing diets with purified condensed tannins decreased (P < 0.05) methane emission by 51 to 60%. A 49.08 g supplementation level with purified condensed tannins per kg DM diet was calculated, with the use of quadratic equations, to result in the lowest methane emission by male Bapedi sheep. The meat of male Bapedi rams on diets containing 30, 40 or 50 g of purified condensed tannins per kg DM contained higher (P < 0.05) antioxidant activities than those from rams fed a diet without purified condensed tannins. These results indicate that purified condensed tannin supplementation levels of 0, 30, 40 or 50 g/kg DM diet had no adverse effects on growth performance, blood profiles and meat sensory attributes of male Bapedi sheep. However, supplementation levels of 30, 40 or 50 g of purified condensed tannins per kg DM diet reduced methane emission by 51 to 60%, and increased sheep meat antioxidant activity values. Supplementing diets with purified condensed tannins has the potential to reduce methane production and emission by sheep. However, long-term studies are recommended to ascertain the present findings.

Effects of Supplementing Finishing Goats with Mitragyna speciosa (Korth) Havil Leaves Powder on Growth Performance, Hematological Parameters, Carcass Composition, and Meat Quality

The objective of this study was to see how dried Mitragyna speciosa Korth leaves (DKTL) affected growth, hematological parameters, carcass characteristics, muscle chemical composition, and fatty acid profile in finishing goats. In a randomized complete block design, twenty crossbred males (Thai Native x Boer) weaned goats (17.70 ± 2.50 kg of initial body weight (BW)) were provided to the experimental animals (5 goats per treatment) for 90 days. Individual dietary treatments of 0, 2.22, 4.44, and 6.66 g/d of DKTL on a dry matter basis were given to the goats. The diets were provided twice daily as total mixed rations ad libitum. In comparison to the control diet, DKTL supplementation had no effect on BW, average daily gain (ADG), feed conversion ratio (FCR), carcass composition, meat pH, or meat color (p > 0.05). After DKTL treatment, the hot carcass weight, longissimus muscle area, oleic acid (C18:1n9), monounsaturated fatty acid (MUFA), and protein content increased, but saturated fatty acids (SFA) and ether extract decreased (p < 0.05). To summarize, DKTL supplementation can improve goat meat quality.

Flesh quality of hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) fed with hydrolyzed porcine mucosa-supplemented low fishmeal diet

Iso-nitrogenous and iso-lipidic diets containing 0%, 3%, 6%, 9%, and 12% hydrolyzed porcine mucosa (namely, HPM0, HPM3, HPM6, HPM9, and HPM12) were prepared to evaluate their effects on the growth performance, muscle nutrition composition, texture property, and gene expression related to muscle growth of hybrid groupers (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂). Groupers were fed to apparent satiation at 08:00 and 16:00 every day for a total of 56 days. It was found that the weight gain percentage in the HPM0, HPM3, and HPM6 groups did not differ (P > 0.05). The cooking loss and drip loss of the dorsal muscle in the HPM3 group were lower than those in the HPM6 and HPM9 groups (P < 0.05). The hardness and chewiness of the dorsal muscle in the HPM3 group were higher than those in the HPM0, HPM9, and HPM12 groups (P < 0.05). The gumminess in the HPM3 group was higher than that in the HPM9 and HPM12 groups (P < 0.05). The total essential amino acid content of the dorsal muscle in the HPM12 group was higher than that in the HPM0 group (P < 0.05). The contents of total n-3 polyunsaturated fatty acid and total n-3 highly unsaturated fatty acid, as well as the ratio of n-3/n-6 polyunsaturated fatty acid in the dorsal muscle was higher in the HPM0 group than in all other groups (P < 0.05). The relative expressions of gene myogenic factor 5, myocyte enhancer factor 2c, myocyte enhancer factor 2a, myosin heavy chain, transforming growth factor-beta 1 (TGF-β1), and follistatin (FST) were the highest in the dorsal muscle of the HPM3 group. The results indicated that the growth performance of hybrid grouper fed a diet with 6% HPM and 27% fish meal was as good as that of the HPM0 group. When fish ingested a diet containing 3% HPM, the expression of genes TGF-β1 and FST involved in muscle growth were upregulated, and then the muscle quality related to hardness and chewiness were improved. An appropriate amount of HPM could be better used in grouper feed.

Sainfoin in the Dams’ Diet as a Source of Proanthocyanidins: Effect on the Growth, Carcass and Meat Quality of Their Suckling Lambs

Sainfoin (Onobrychis viciifolia) is a forage legume with a medium content of proanthocyanidins (PAC), which may affect animal performance and product quality. The objective of the present study was to assess the effect of PAC from sainfoin fed to dams, using polyethylene glycol (PEG) as a blocking agent, on the performance and carcass and meat quality of their suckling male lambs. After lambing, twenty lactating dams were fed fresh sainfoin ad libitum plus 200 g per day of barley; ten were orally dosed with water (Sainfoin), and ten were dosed orally with a water dilution of 100 g PEG (Sainfoin + PEG). Their lambs (4.1 ± 0.64 kg at birth) suckled ad libitum until they reached the target slaughter weight of 10–12 kg. The presence of PAC in the dams’ diet did not affect the growth, blood metabolites and carcass weight and fatness of the suckling lambs but decreased the lightness of caudal fat (p < 0.05) and increased the weight of the digestive compartments (p < 0.05). Regarding the meat characteristics, PAC only decreased polyphenols content (p < 0.05). In conclusion, the presence of PAC in the dams’ diet had not significant effects on the performance and product quality of their suckling lambs.

Nitrite Stress Induces Oxidative Stress and Leads to Muscle Quality Decreased in Wuchang Bream (Megalobrama amblycephala Yih) Juveniles

To determine the effects of nitrite exposure on muscle quality and physiological functions in Wuchang bream (Megalobrama amblycephala), we exposed M. amblycephala juveniles to acute nitrite (0, 1, 5, 10, 20 mg/L), and the muscle and blood samples were measured at 12, 24, 48, and 96 h. The results showed that when exposed to nitrite for 12 h, the concentrations of blood glucose, cortisol, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in the 20 mg/L experimental group had the maximum value. The activity of lactate dehydrogenase (LDH) increased significantly in a dose-dependently manner and peaked at 96 h in the 20 mg/L group. During 96 h of exposure to nitrite, the total antioxidant capacity (T-AOC) and catalase (CAT) activity in the liver of the 20 mg/L experimental group were significantly higher than those of the control group, while the concentration of muscle glycogen showed a downtrend. At 12 h and 96 h, the hardness of the four experimental groups were significantly higher than that of the control group. Our research shows that acute sodium nitrite exposure will not only cause oxidative stress and decreased muscle quality in M. amblycephala juveniles but also will be accompanied by changes in serum biochemical index, liver antioxidant capacity, muscle physiological characteristics, and muscle physical characteristics. Preliminary speculation may be that acute nitrite exposure may cause M. amblycephala juveniles to choose to reduce muscle quality and activate antioxidant systems.

Incorporation of Herbal Plants in the Diet of Ruminants: Effect on Meat Quality

The use of herbal plants as food additives in animal nutrition to enhance meat processing efficiency and meat quality has been reviewed. Today, the consumer demand is safety, nutritive value, taste, uniformity, meat variety, and good appearance of meat products. Thus, to meet the consumers' demand, development of product and research should be improved. Studies have been shown that the use of herbs, spices, and their extracts are of the major interventions, which were adopted in the industry of the meat for improving its quality traits. In the present paper, the most recent literature about use of bioactive compounds in herbal plants for evaluating a number of parameters related to meat quality, including fat content and distribution, water content, water holding capacity, collagen content, pH, tenderness color, lipid oxidation and flavor were reviewed.

Condensed Tannins as Antioxidants in Ruminants-Effectiveness and Action Mechanisms to Improve Animal Antioxidant Status and Oxidative Stability of Products

Condensed tannins (CTs) are widely distributed in plants, and due to their recognized antioxidant activity are considered as possible natural antioxidants for application in ruminant diets. A wide range of CT-rich sources has been tested in ruminant diets, and their effects on animal antioxidant status and oxidative stability of their products are reviewed in the present work. Possible mechanisms underlying the CT antioxidant effects in ruminants are also discussed, and the CT chemical structure is briefly presented. Utilization of CT-rich sources in ruminant feeding can improve the animals' antioxidant status and oxidative stability of their products. However, the results are still inconsistent. Although poorly understood, the evidence suggests that CTs can induce an antioxidant effect in living animals and in their products through direct and indirect mechanisms, which can occur by an integrated and synergic way involving: (i) absorption of CTs with low molecular weight or metabolites, despite CTs' poor bioavailability; (ii) antioxidant action on the gastrointestinal tract; and (iii) interaction with other antioxidant agents. Condensed tannins are alternative dietary antioxidants for ruminants, but further studies should be carried out to elucidate the mechanism underlying the antioxidant activity of each CT source to design effective antioxidant strategies based on the use of CTs in ruminant diets.

Effects of grape pomace supplementation on the diet of lactating ewes as compared to vitamin E on the meat shelf life of suckling lambs

Forty-eight Churra ewes and their suckling lambs were assigned to four dietary treatments: control (CTRL), VIT-E (500 mg kg-1 TMR vitamin E), GP-5 (5% grape pomace) and GP-10 (10% grape pomace). After slaughter (11.5 kg live weight), longissimus muscle of lambs was sliced, packaged under modified atmosphere (80,20%/O 2:CO 2) and stored in retail conditions. At each sampling point (0, 3, 7, 10, 14 days), microbiological, physicochemical and sensory characteristics were analysed. Vitamin E and GP-5 were found to be effective (p < 0.05) at preventing enterobacteria growth as of day 10. After day 10, vitamin E and grape pomace in the ewe's supplementation reduced metmyoglobin (p < 0.05) lipid oxidation (p < 0.05) and sensory spoilage throughout the storage period. An effect of the grape pomace dosage was observed, with the supplementation at 5% being more effective. Therefore, we can conclude that grape pomace was just as effective as vitamin E in preventing spoilage during retail storage.

Tropical grass and legume pastures may alter lamb meat physical and chemical characteristics

The present study assessed the influence of the type of the tropical pastures on lamb body weight (BW) gain and meat quality. Fifty-four lambs were allocated to three grazing pastures: (1) AG - Aruana grass (Panicum maximum cv. IZ-5); (2) PP - pigeon pea legume (Cajanus cajan cv. Anão); and (3) CS - contiguous swards, half of the paddock with AG and half with PP. After 92 days of grazing, the lambs were slaughtered. Carcasses were evaluated and the longissimus muscle was collected to determine color, lipid profile, tocopherol concentrations, and lipid oxidation. Although the pastures present differences in the characteristics of nutritional quality, the animals did not show difference in BW gain. The results show that all forage presented similar concentration of alpha-tocopherol (137 ± 14.37 mg kg^-1 of fresh matter), whereas total and condensed tannin contents were greater in PP, intermediate in CS, and the lowest in AG treatment (P = 0.0001). Meat α-tocopherol content was similar among treatments (P = 0.1392), with an average concentration close to the optimal level to reduce the meat oxidation. Meat from AG treatment had 45 and 25% lower n-6/n-3 ratio than meat from PP and CS treatments, respectively. The legume increases the unsaturated fatty acids and the grass can reduce the n6/n3 ratio. The level of condensed tannin concentration did show to have important effect on meat characteristics. Both tropical pastures studied can provide a high amount of alpha-tocopherol, generating a great potential to increase the concentration of this antioxidant in lamb's meat.

The effect of plant bioactive compounds on lamb performance, intake, gastrointestinal parasite burdens, and lipid peroxidation in muscle

Plant extracts have been widely used in animal production systems due to the benefits promoted by their bioactive components, mainly through their antioxidant effects and positive effects on animal growth, health, and meat quality. We determined whether bioactive compounds (BC) from grape (Vitis vinifera), olive (Olea europaea), and pomegranate (Punica granatum) have beneficial effects on lamb growth while controlling gastrointestinal parasitism and reducing skeletal lipid peroxidation in muscle. Fourteen lambs (4 to 5 mo of age) were housed in individual pens and assigned to two treatment groups (seven animals/group), where they received: 1) a basal diet of beet pulp:soybean meal (90:10) (CONTROL) and 2) the same diet, but containing 0.3% of BC extracted from grape, olive, and pomegranate (BNP). After 21 d of consuming their respective rations (period 1), all lambs were dosed with 10,000 L3 stage larvae of Haemonchus contortus. Intake, production, and physiological parameters were determined before infection (period 1), after oral dosage with L3 (period 2), and during early (period 3) and later (period 4) developmental stages of infection. Groups of animals did not differ in their ration intake or average daily gain, either before or after the infection, or in their parasitic burdens estimated through fecal egg counts (P > 0.05). Lambs under BNP showed greater feed efficiency before infection (P < 0.001), but the pattern reversed after infection. In addition, the inclusion of plant bioactives to the diet did not have an effect (P > 0.05) on blood or lipid peroxidation in muscle or on hemogram, serum concentration of haptoglobin, and immunoglobulin E. These results could be explained by low dietary doses and constrained absorption or ruminal inactivation of these compounds. Changes in feed efficiencies suggest a negative interaction between BC in the diet and parasitism, which warrants further research.

Effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs

Ruminants can tolerate moderate concentrations of dietary tannin, making it feasible to replace corn with sorghum in ruminant diets; however, conditioning temperature of pelleted total mixed ration (PTMR) greatly affects nutrient digestibility. The objective was to determine effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs. This was a 2 × 3 factorial study, with corn and sorghum and three conditioning temperatures (65, 75 and 85 °C) in a randomized complete design, with 36 lambs (120 ± 10.2 d and 24.9 ± 3.3 kg) grouped by weight and randomly allocated. The resulting six PTMRs were referred to as 65-S, 75-S and 85-S for sorghum-based diets, and 65-C, 75-C and 85-C for corn-based diets, for low, medium and high pelleting temperatures, respectively. There was no grain type × conditioning temperature (Grain × Temp) interaction on growth performance and apparent nutrient digestibility. Furthermore, grain type did not affect DM intake (DMI), average daily gain (ADG) or feed conversion ratio (FCR) of fattening lambs. Pelleting at 75 °C improved ADG (P < 0.03) and FCR (P < 0.02) of fattening lambs compared to other temperatures. There was a Grain × Temp interaction (P < 0.01) on ruminal pH (lowest in lambs fed 75-S). There tended (P = 0.07) to be a Grain × Temp interaction for total volatile fatty acid (VFA), and there were Grain × Temp interactions for molar proportions of acetate (P < 0.04), butyrate (P < 0.03) and branch-chained VFA (P < 0.01). Lambs fed sorghum-based PTMR had greater molar proportion of propionate (P < 0.03) and lower acetate to propionate ratio (A:P, P < 0.04). Lambs fed sorghum-based PTMR had higher plasma concentrations of urea nitrogen (N) (P < 0.03), glucose (P < 0.01) and alkaline phosphatase (P < 0.05), whereas other blood metabolites were not affected by treatments. There were Grain × Temp (P < 0.03) interactions for color coordinates of longissimus and mid-gluteal muscle. Lambs fed sorghum-based PTMR had lower (P < 0.01) dressing percentage and meat quality than those fed corn-based PTMR. We concluded that sorghum can replace corn in lamb diets without compromising growth performance and feed efficiency; furthermore, feeding sorghum vs corn improved rumen fermentation, with reduced A:P ratio and enhanced N and glucose utilization. Finally, pelleting at 75 °C increased feeding value of either sorghum- or corn-based PTMR for fattening lambs.

MARGRA Lamb Eating Quality and Human Health-Promoting Omega-3 Long-Chain Polyunsaturated Fatty Acid Profiles of Tattykeel Australian White Sheep: Linebreeding and Gender Effects

Health-conscious consumers increasingly demand healthier, tastier, and more nutritious meat, hence the continuous need to meet market specifications and demand for high-quality lamb. We evaluated the longissimus dorsi muscle of 147 Tattykeel Australian White (TAW) sheep fed on antioxidant-rich ryegrass pastures exclusive to MAGRA lamb brand for meat eating quality parameters of intramuscular fat (IMF) content, fat melting point (FMP) and omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). The aim was to assess the impact of linebreeding and gender on pasture-fed lamb eating quality and to test the hypothesis that variation in healthy lamb eating quality is a function of lamb gender and not its antioxidant status or inbreeding coefficient (IC). After solid-phase extraction and purification, phenolics and antioxidant enzyme activities were analysed by high-performance liquid chromatography and mass spectrometry. IMF and fatty acid composition were determined using solvent extraction and gas chromatography, respectively. IC was classified into low (0-5%), medium (6-10%) and high (>10%) and ranged from 0-15.6%. FMP and IMF ranged from 28 to 39 °C and 3.4% to 8.2%, with overall means of 34.6 ± 2.3 °C and 4.4 ± 0.2%, respectively, and n-3 LC-PUFA ranged from "source" to "good source" levels of 33-69 mg/100 g. Ewes had significantly (P ˂ 0.0001) higher IMF, C22:5n-3 (DPA), C22:6n-3 (DHA), C18:3n-6, C20:3, C22:4n-6, C22:5n-6, total monounsaturated (MUFA), PUFA and Σn-3 fatty acids and lower total saturated fatty acids (SFA) and FMP, than rams. As IC increased, there were no differences in FMP and IMF. Folin-Ciocalteu total phenolics, ferric reducing antioxidant power and antioxidant activities of glutathione peroxidase, catalase and superoxide dismutase enzymes did not differ by either gender or IC. This study provides evidence that IC is inconsequential in affecting antioxidant status, IMF, FMP and n-3 LC-PUFA in linebred and pasture-fed TAW sheep because the observed variation in individual fatty acids was mainly driven by gender differences between ewes and rams, hence the need to accept the tested hypothesis. This finding reinforces the consistent healthy eating quality of MARGRA lamb brand from TAW sheep regardless of its linebred origin.

Volatile Organic Compounds, Oxidative and Sensory Patterns of Vacuum Aged Foal Meat

The study aimed to evaluate the effect of 14-day vacuum aging on the volatile compounds (VOC) profile, oxidative profile, antioxidant enzymes activity, and sensory evaluation in the Longissimusthoracis muscle of foal meat under vacuum aging. Longissimusthoracis (LT) was sampled in 20 mm thick slices, vacuum packed, and stored at 4 °C. Samples were randomly assigned to different aging times (1, 6, 9, 14 days after slaughtering). VOCs, thiobarbituric acid reactive substances (TBARs), hydroperoxides, carbonyl proteins, superoxide dismutase, catalase, and glutathione peroxidase were analyzed, and a sensory test was performed. A nested one-way analysis of variance (ANOVA) was performed for aging time as an independent variable. Significance was set at p < 0.05. The main VOCs originating from cooked steaks were aldehydes, (from 47.18% to 58.81% of the total volatile compounds), followed by hydrocarbons (from 9.32% and 31.99%). TBARs and hydroperoxides did not show variations due to aging (p > 0.05), instead, protein carbonyls showed higher values at the 14th day (p < 0.01). Catalase, superoxide dismutase, and glutathione peroxidase showed increasing values during aging time (p < 0.01). Vacuum aging slowed down lipid oxidation, and protein oxidation was shown to be present. However, the best vacuum aging duration is in the range of 6-9 days from slaughtering, with an improvement of sensory evaluation.

Effects of dietary grapeseed extract on performance, energy and nitrogen balance as well as methane and nitrogen losses of lambs and goat kids

The influence of phenol-rich dietary grapeseed extract on performance, energy and N balance and methane production was determined in sixteen lambs and thirteen goat kids (body weight 20·5 and 19·0 kg, 2 months of age, day 1 of study). Half of the animals received a concentrate containing grapeseed extract, and the others received concentrate without grapeseed extract (total extractable phenols analysed 27 v. 9 g/kg dietary DM; concentrate and hay 1:1). Diets were fed for 7 weeks with 1 week for determining intake, excretion and gaseous exchange in metabolism crates and respiration chambers. Overall, there was an adverse effect of the phenolic diet on apparent N digestibility and body N retention. Faecal N loss as proportion of N intake increased while urinary N loss declined. Relative to N intake, total N excretion was higher and body N retention lower in goat kids than lambs. Diets and animal species had no effect on methane emissions. The saliva of the goat kids had a higher binding capacity for condensed tannins (CT). Goat kids on the phenolic diet had higher CT concentrations in faeces and excreted more CT compared with the lambs (interaction species × diet P < 0·001). The lambs had overall higher (P < 0·001) urinary phenol concentrations than the goat kids (2·19 v. 1·48 g/l). The negative effect on body N retention and lack of effect on methane emissions make the use of the extract in the dosage applied not appealing. Species differences need to be considered in future studies.

Characterization of moisture migration of beef during refrigeration storage by low-field NMR and its relationship to beef quality

BACKGROUND

In this study, low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) were used to investigated the moisture migration of beef during refrigeration storage, and its relationships to some physicochemical quality indicators were analyzed using partial least squares regression.

RESULTS

Three water components ascribed to bound water, immobilized water and free water in beef matrix were revealed by LF-NMR relaxation results. The transverse relaxation time and peak area of immobilized water declined as storage proceeded, as a result of disruption to the microstructure revealed by scanning electron microscope images. MRI images found obvious water migration of beef during refrigeration storage, and scanning electron microscopy images revealed that the integrity of the muscle fiber bundle was destroyed. In addition, increased storage time also led to increases in pH, total volatile basic nitrogen, TBARS (thiobarbituric acid reactive substances) value, weight loss, cooking loss and b* value, and to decreases in water holding capacity (WHC), L* and a* values, and textural properties.

CONCLUSION

The strong correlations between water migration and the physicochemical quality changes suggested the possibility of LF-NMR as a rapid and non-invasive method to evaluate beef quality. © 2019 Society of Chemical Industry.

Influence of tannin-rich pine bark supplementation in the grain mixes for meat goats: Growth performance, blood metabolites, and carcass characteristics

The objective was to evaluate the use of condensed tannin (CT)-rich ground pine bark (PB) in grain mixed diets on meat goat growth performance, blood metabolites, and carcass characteristics. Twenty four Kiko crossbred (Capra aegagrus hircus) growing male kids (BW = 36.9 ± 2.5 kg) at approximately 8 months of age were assigned randomly to 2 treatments with 3 replicates per treatment and 4 goats per replicate. The goats were fed grain mixed diets composed of either 30% bermudagrass hay (BGH) plus concentrate (control) or 30% PB plus concentrate. Diets were fed at 1.2% of BW. In addition, all goats grazed a crabgrass/bermudagrass (CB)-based pasture. The feeding trial lasted for 55 d. Using ground PB as a supplement did not negatively affect BW, average daily gain (ADG), carcass characteristics, meat pH, and meat color compared to the control diet. Plasma gamma-glutamyl transferase (P = 0.03), glucose (P < 0.01) and Ca concentrations (P = 0.04) were higher for PB than for BGH, respectively. The 30% PB supplementation does not negatively affect animal performance, blood metabolites, and carcass parameters.

Dietary thymol supplementation promotes skeletal muscle fibre type switch in longissimus dorsi of finishing pigs

As one of the key points related to meat quality, skeletal muscle fibre type is determined by energy metabolism and genetic factors, but its transformation could be also greatly influenced by many factors. Thymol, the primary effective ingredients of thyme, is well known for its anti-oxidation and anti-inflammatory, while little is known about its effect on skeletal muscle oxidative metabolism and fibre type switch. Therefore, in order to investigate its effects and possibility to be applied in livestock production, 36 150-day-old fattening Pigs were fed with different diet for six-week experiment. As a result, the drip loss ratio of longissimus dorsi (LD) was significantly reduced (p < .05). Oxidative metabolism-related enzyme activity, the mRNA levels and protein expression of COX5B and PGC1α, mRNA level of myosin heavy chain I (MyHC I) and protein level of MyHC IIa were significantly upregulated (p < .05). While compared with control group, the protein expression of MyHC IIb was significantly decreased (p < .05). The result revealed that thymol could promote the oxidative metabolism in the muscle of pigs and improve the meat quality to a certain extent.

Effects of aging and dietary supplementation with polyphenols from Pinus taeda hydrolysed lignin on quality parameters, fatty acid profile and oxidative stability of beef

Context The inclusion of Pinus taeda hydrolysed lignin (PTHL) in beef diets could improve quality and stability of meat, but effects could vary through the aging period (AP). Aim The aim was to evaluate the effects of the PTHL inclusion in the diet of finishing beef cattle on meat quality, fatty acid composition and oxidative stability at Days 1, 8, 11 and 15 of aging. Methods Forty Limousin bulls (340 ± 42 kg) were fed ad libitum on a total mixed ration (TMR). The control group received exclusively TMR for 120 days, while the experimental group received the same TMR as the control group but supplemented with PTHL (Oxifenol, I-Green, Padua, Italy; 35 g/day per head at 1–90 days and 70 g/day per head at 91–120 days). Key results Diet did not influence the chemical composition, pH, cooking loss, Warner–Bratzler shear force and hydroperoxide content. The Warner–Bratzler shear force (P &lt; 0.001) decreased, while lightness (P &lt; 0.01) and hydroperoxides (P &lt; 0.001) increased through the aging period. Thiobarbituric acid reactive substances were similar for both diets at 1 and 15 days. However, thiobarbituric acid reactive substances at 8 and 11 days were higher for control than for the PTHL diet (P = 0.023 for interaction). Protein carbonyls were higher for control than for the PTHL diet at 8 days (P = 0.003 for interaction), but similar for both diets for the other dates. Saturated, monounsaturated and polyunsaturated fatty acids varied through the AP with PTHL diet, while no changes were observed with control diet (P &lt; 0.01 for interactions). At 11 days, the n-6:n-3 ratio passed from being the minimum value with the PTHL diet to be the maximum with control diet (P &lt; 0.01 for interaction). Conclusions The effects of PTHL inclusion in bull finishing diets depends on the AP but, generally, may result in beef with meat with beneficial effects on human health. Implications Including PTHL in the diet of finishing bulls can be useful to improve meat quality, favouring the use of natural waste substances deriving from vegetal production.

Dietary Supplementation of Tannin-Extracts to Lambs: Effects on Meat Fatty Acids Composition and Stability and on Microbial Characteristics

Two extracts derived from plant material rich in hydrolysable (Tara, T; Caesalpinia spinosa) or condensed (Mimosa, M; Acacia mearnsii) tannins were added to lamb's diet and their effects on meat quality and on microbial population were evaluated; a diet without tannins represented the Control (C). Meat pH, vitamin E, intramuscular fat content and muscle fatty acid composition were determined. Oxidative stability and microbiological analyses were performed on meat samples after 0, 4 and 7 days of refrigerated storage. Psychrotrophic bacteria were identified through MALDI-TOF MS analysis. Regarding meat fatty acids, Tara treatment decreased the percentage of monounsaturated fatty acids. The counts of all microbial groups were similar among dietary treatments at day 0, while a significant reduction of microbial loads was observed in T-group at day 7. Pseudomonas fluorescens group count was significantly affected by T extract supplementation. The MALDI-TOF MS identification revealed the dominance of Pseudomonas fragi species in all samples while Pseudomonas lundensis, Brochothrix thermosphacta and Candida famata were revealed only in control ones. In conclusions, the tannin extract supplementation is a promising dietary strategy to preserve lamb meat quality.

Effect of Chestnut Tannins and Short Chain Fatty Acids as Anti-Microbials and as Feeding Supplements in Broilers Rearing and Meat Quality

Simple Summary

The poultry industry needs to replace antibiotics with natural or synthetic compounds able to overcome problems linked to the development of bacterial resistance. Tannins and short chain fatty acids are valid alternatives to contrast the growth of pathogens. However, tannins may induce detrimental effects on animal performances, especially in monogastrics, causing damage on gut villi. In contrast, short chain fatty acids are very efficient in influencing positively the morphology of small intestine wall. Hence, the aim of this trial was to develop a feeding strategy for broiler rearing, based on the use of chestnut tannins and short chain fatty acids administered as blends. No differences in animal performances or in meat quality were found among feeding groups. The results suggested that the mix of these supplements did not have negative effects on the productive performances, representing a promising alternative to antibiotics. However, further investigation is needed to better understand the effects of these supplements on animals in stress conditions.

Abstract

Chestnut tannins (CT) and saturated short medium chain fatty acids (SMCFA) are valid alternatives to contrast the growth of pathogens in poultry rearing, representing a valid alternative to antibiotics. However, the effect of their blends has never been tested. Two blends of CT extract and Sn1-monoglycerides of SMCFA (SN1) were tested in vitro against the proliferation of Clostridium perfringens, Salmonella typhymurium, Escherichia coli, Campylobacter jejuni. The tested concentrations were: 3.0 g/kg of CT; 3.0 g/kg of SN1; 2.0 g/kg of CT and 1.0 g/kg of SN1; 1.0 g/kg of CT and 2.0 g/kg of SN1. Furthermore, their effect on broiler performances and meat quality was evaluated in vivo: one-hundred Ross 308 male birds were fed a basal diet with no supplement (control group) or supplemented with CT or SN1 or their blends at the same concentration used in the in vitro trial. The in vitro assay confirmed the effectiveness of the CT and SN1 mixtures in reducing the growth of the tested bacteria while the in vivo trial showed that broiler performances, animal welfare and meat quality were not negatively affected by the blends, which could be a promising alternative in replacing antibiotics in poultry production.

Meat quality from pigs fed tomato processing waste

Sixteen Nero Siciliano pigs were used to investigate the effect of dietary tomato processing waste on meat quality. During 86 days one group (CON, n = 8) received a pelleted conventional diet, while another group (TOM, n = 8) received the same diet in which tomato waste replaced 15% of corn. The dietary treatment did not affect growth performances. The TOM diet reduced intramuscular fat, SFA and MUFA content, while increasing the n-6:n-3 ratio in meat (P < .05). The TOM diet increased the concentration of PUFA, PUFA n-3, PUFA n-6 and the n-6:n-3 ratio (P < .01). The instrumental colour descriptors of backfat were unaffected by diet. The TOM diet increased deposition of retinol in meat (P < .001) but did not affect oxidative stability parameters measured in fresh meat and meat homogenates with pro-oxidant catalysts. Concluding, tomato pomace fed to pigs at higher levels compared to previous reports had no adverse effects on the investigated meat quality traits.

Peanut skin in diet alters average daily gain, ruminal and blood metabolites, and carcass traits associated with Haemonchus contortus infection in meat goats

The aim of this study was to determine the effects of tannin-rich peanut skin (PS) supplementation on growth performance, ruminal and blood metabolites, and carcass traits associated with internal parasite infection in meat goats under confined conditions. Twenty-one Kiko crossbred male goats were blocked by body weight (BW) and randomly assigned to one of 3 treatment groups. Experimental diets contained different levels of peanut (Arachis hypogaea) skin replacing alfalfa (Medicago sativa) pellets (ALP) in a control diet. Experimental treatments included: 30% ALP (control), 15% PS and 15% ALP, and 30% PS. Peanut skin was incorporated in the grain mix portion of the diets. Animals were fed once daily, and the intake was adjusted every 3 to 4 d. Each animal was each artificially infected with 5,000 larvae of the 3rd stage of barber's pole worm (Haemonchus contortus). Body weights, dry matter intake (DMI), and fecal samples for fecal egg counts (FEC) were taken at d 0, 12, 23, and 41. Rumen fluid and blood samples were collected at d 45. The performance period lasted 45 d and at the completion of the study, goats were harvested, and carcass characteristics, abomasal worm counts were measured. The results showed that DMI, BW, carcass traits, and meat color were not affected by PS supplementation, whereas average daily gain (ADG, P < 0.01), blood glucose (P < 0.001), phosphorus (P < 0.05), and cholesterol levels (P < 0.001) significantly increased with increasing levels of PS supplementation. There was a linear (P < 0.01) reduction in rumen acetate to propionate ratio, ammonia-nitrogen, FEC, and H. contortus worm counts, with increasing levels of PS supplementation. This study shows that PS supplementation up to 30% of the diet can improve ADG and rumen fermentation while reducing gastrointestinal parasite infection in meat goats.

Improvement of Muscle Quality of Grass Carp (Ctenopharyngodon idellus) With a Bio-Floating Bed in Culture Ponds

Muscle quality and the physiological condition of fish are affected greatly by the culture environment. In aquaculture ponds, a bio-floating bed planted with vegetation is often used to improve water quality. This study investigated the growth and muscle quality of grass carp (Ctenopharyngodon idellus) cultured in ponds equipped with bio-floating beds. Fish were cultured in two replicated pond groups from May to November. Fish in the first group were cultured in experimental ponds equipped with a bio-floating bed planted with Ipomoea aquatica, whereas fish in the other group were reared in control ponds without a bio-floating bed. Compared with control ponds, the experimental ponds had better water quality with significantly lower concentrations of nitrite and ammonia. Grass carp in the experimental group had greater muscle weight gain, a significantly higher content of crude protein, and a significantly lower crude fat level than fish in the control group. The levels of pH, water-holding capacity, and antioxidant capacity of muscle decreased significantly in the control group compared to the experimental group. Texture profile analysis revealed higher values of hardness, springiness, gumminess, and chewiness and lower values of cohesiveness and resilience of white muscle in the experimental group compared to the control group. The filets of fish in the experimental group also received higher grades in the sensory evaluation of springiness, overall acceptability, aroma, and palatability. These results indicate that growth performance and muscle quality of grass carp were improved by the presence of bio-floating beds in the culture ponds.

Effects of flavonoids from Allium mongolicum Regel as a dietary additive on meat quality and composition of fatty acids related to flavor in lambs

Sixty male Small-tailed Han sheep (initial body weight: 42.5 ± 4.1 kg) were assigned randomly and averagely into four groups to evaluate effects of flavonoids extracted from Allium mongolicum Regel (AMR) on meat quality and composition of fatty acids related to flavor in longissimus dorsi muscle of lambs. Lambs of four groups were fed a basal control diet (C), and basal diet + three different amounts of flavonoids extracted from the AMR; those were 11 mg kg−1 (Flav 11), 22 mg kg−1 (Flav 22), or 33 mg kg−1 (Flav 33), respectively. Dressing percentage, loin eye area, cooking loss, and pressing loss were affected by treatments (P < 0.05). Percentage of intramuscular fat, the concentrations of eicosapentaenoic acid, C18:0, total saturated fatty acids, monounsaturated fatty acid, and 4-methyloctanoic acid in longissimus dorsi muscle were changed by treatments (P < 0.05). Addition of AMR to diet improved the meat quality and had favorable effects on fatty acid composition related to meat flavor in longissimus dorsi muscle.

Enhanced oxidative stability of meat by including tannin-rich leaves of woody plants in goat diet

Objective

The aim of this study was to evaluate the effect of dietary incorporation of tannin-rich woody species on meat oxidative stability, carcass traits and meat quality in goats.

Methods

Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat.

Results

Feed intake, liveweight gain, carcass and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups.

Conclusion

The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.

Effects of tannin-containing diets on performance, gut disease control and health in broiler chicks

The emergence of antibiotic-resistant bacteria in the intestinal microbiota of broiler chickens, and the possibility of antibiotic residues in meat and meat products are seen as a threat to animal and human health. The search for alternatives to conventional drugs, including natural compounds, is an interesting approach to prevent the adverse effects of antibiotics. Therefore, the aim of the present study was to evaluate whether the addition of tannin (as a quebracho extract) in the diet of broiler chickens could be used to replace in-feed antimicrobials and coccidiostatic drugs, to exert positive effects on animal health and performance. The use of tannin in the diet of broiler chicks as an additive (at 0.5% for 1–10-day-old birds; and 1.0% for 11–42-day-old broiler chickens) enhanced their bodyweight, weight gain and daily weight gain on Day 42 of life, compared with the untreated control group (P &lt; 0.05). However, these findings were not observed when tannin was added at 0.5%. Moreover, broiler chickens fed with an extract containing tannins showed higher erythrocyte counts, as well as haemoglobin and haematocrit concentrations than did those in the control group, whereas counts of total leukocytes and lymphocytes were lower (P &lt; 0.05). The use of a diet with tannins did not influence meat quality compared with a diet containing zinc bacitracin and salinomycin, which altered some parameters associated with meat colour. Moreover, the diet with tannins reduced (P &lt; 0.05) the number of oocysts of Eimeria sp. (36-day-old broilers) and the total faecal bacterial counts (42-day-old broilers) compared with the control group. Finally, intestinal histopathology showed that the addition of tannins minimised the degree of lesions (Degree 1) compared with the control group (Degree 3). On the basis of these results, we concluded that the use of quebracho extract containing tannins can be a suitable approach to improve the performance of broiler chickens, replacing in-feed antibiotics and coccidiostatic drugs. The use of tannins did not change meat quality; however, it caused positive effects on the immune system, and exerted potent bactericidal and coccidiostatic properties, reinforcing its use as a replacement for conventional drugs.

Physicochemical characteristics and fatty acid composition of the meat of lambs fed cassava silage and dry tamarind (Tamarindus indica)

The objective of the present study was to determine the effect of the addition of dry tamarind (Tamarindus indica L.) residue to cassava (Manihot esculenta, Crantz) silage on the carcass traits, quality and fatty acid profile of lamb meat. Forty 6-month-old (±2 days) castrated lambs (crossbred Santa Ines × mixed breed) with initial bodyweights of 22.1 ± 3.0 kg were used in a completely randomised design with four treatments (0, 100, 200 or 300 g/kg of DM of dry tamarind residue) and 10 replicates (animals). There was a significant increase in hot carcass weight (P &lt; 0.001) and loin weight (P = 0.04); however, there were no effects on final bodyweight, average daily weight gain, slaughter weight, weights of other commercial cuts, shear force, lightness (L*), redness (a*), yellowness (b*), chroma (C*), lipid profile, ash content, initial and final pH value and cooking weight loss. There was a significant (P &lt; 0.001) quadratic reduction in water-holding capacity with an increasing tamarind residue content. The addition of tamarind residue to cassava silage linearly decreased the lauric (C12:0; P = 0.01) and stearic (C18:0; P = 0.01) fatty acid concentrations (total saturated fatty acids, ΣSFA) (P = 0.03) and the ratio of ΣSFA to unsaturated fatty acids (ΣSFA:ΣUFA; P = 0.04). However, there were linear increases in the C18:2 cis9, cis12 concentration (P = 0.04), polyunsaturated fatty acid n-6 concentration (P = 0.05), ΣUFA (P = 0.03) and the Σn-6:Σn-3 ratio (P = 0.01) in the lamb meat. Dry tamarind can be added to cassava up to a level of 300 g/kg of DM without any negative effects on the performance or meat quality, and it increases the yield of the loin cut, polyunsaturated fatty acid n–6 and ΣUFA, which makes the lamb meat healthier.