Antioxidant status, colour stability and myoglobin resistance to oxidation of longissimus dorsi muscle from lambs fed a tannin-containing diet

Dietary hazelnut skin prevents lipid oxidation in lamb enriched in omega-3 polyunsaturated fatty acids

The aim of this study was to investigate the effect of partially replacing maize with hazelnut skin and linseed, alone or in combination, on the oxidative stability of lamb. Forty lambs were randomly assigned to 4 treatments and fed: a conventional cereal-based diet (C), or the same diet with 15 % of hazelnut skin (HS), or 8 % of extruded linseed (LS), or 7.5 % of hazelnut skin plus 4 % of linseed (H + L) as partial replacement of maize. After 60 days of feeding trial, lambs were slaughtered, and hydrophilic antioxidant capacity and fat-soluble vitamins content were evaluated in fresh meat. Colour stability, lipid and protein oxidation were assessed during 7 days of refrigerated storage. Dietary combination of hazelnut skin and linseed increased the content of tocopherols (P < 0.001) and of n-3 polyunsaturated fatty acids (PUFA n-3; P < 0.001), while reducing lipid oxidation (TBARS value) during 7 days of storage (P < 0.001). Feeding lamb with hazelnut skin and/or linseed did not affect meat hydrophilic antioxidant capacity, colour stability, nor the formation of hydroperoxides, thiols, or carbonyls (P > 0.05). These results suggest that vitamin E provided by hazelnut skin contributed to delay lipid oxidation in meat, despite the higher concentration of n-3 PUFA.

Effects of dietary Allium mongolicum Regel powder supplementation on the growth performance, meat quality, antioxidant capacity and muscle fibre characteristics of fattening Angus calves under heat stress conditions

The aim of this study was to investigate the effects of dietary Allium mongolicum Regel powder (AMRP) supplementation on the growth performance, meat quality, antioxidant capacity and muscle fibre characteristics of fattening Angus calves. Growth performance data and longissimus thoracis (LT) samples were collected from four groups of fattening Angus, which were fed either a basal diet (CON) or a basal diet supplemented with an AMRP dose of 10 (LAMR), 15 (MAMR), or 20 g/animal/day AMRP (HAMR) for 120 days before slaughter. AMRP addition to the feed improved growth performance and meat quality and altered muscle fibre type. Some responses to AMRP supplementation were dose dependent, whereas others were not. Together, the results of this study demonstrated that dietary supplementation with 10 g/animal/day AMRP was the optimal dose in terms of fattening calf growth performance, while 20 g/animal/day AMRP supplementation was the optimal dose in terms of meat quality.

Effects of Bergamot (Citrus bergamia Risso) By-Product on Growth Performance and Meat Quality of Growing Rabbits

This study aimed to investigate the effects of feeding dried bergamot pulp to rabbits on animal performance and meat quality. Thirty rabbits were assigned to two groups (balanced for body weight, 804.4 ± 2.35 g) and fed individually for 60 days a basal diet (control) or the basal diet in which part of the cereals was replaced with 10% of dried bergamot pulp (DBP). There were no effects of DBP on growth performance, carcass yield, or the crude protein and ether extract composition of meat. The concentrations of α-linolenic acid (C18:3 n-3) and eicosapentaenoic acid (C20:5 n-3) increased in the longissimus thoracis et lumborum muscle (p < 0.01 and p = 0.021, respectively) after integrating dried bergamot pulp into the diet, leading to higher levels of total of ω-3 fatty acids (p < 0.01) compared to the control treatment. The inclusion of dried bergamot pulp improved the oxidative stability in meat (p < 0.001), where TBARS values were lower after 4 and 7 days of refrigerated storage (p < 0.001) in the DBP group than in the control group. Finally, feeding dried bergamot pulp to rabbits improves meat quality without negatively influencing growth performance.

Bioaccessibility of condensed tannins and their effect on the physico-chemical characteristics of lamb meat

The bioaccessibility of tannins as antioxidants in meat is essential to maximise their effectiveness in protecting the product. This property determines the amount of tannins available to interact with meat components, inhibiting lipid and protein oxidation and, consequently, prolonging shelf life and preserving the sensory quality of the product. The objective of this study was to evaluate the bioaccessibility of condensed tannins (CT) from Acacia mearnsii extract (AME) and their effect on the physico-chemical characteristics of fattened lamb meat. Thirty-six Dorset × Hampshire lambs (3 months old and 20.8 ± 3.3 kg live weight) were used. The lambs were distributed equally (n = 9) into four treatments: T1, T2, T3 and T4, which included a basal diet plus 0%, 0.25%, 0.5% and 0.75% of CT from AME, respectively. At the end of the fattening period, bioaccessibility was evaluated, the animals were slaughtered and a sample of the longissimus dorsi (LD) muscle was collected to assess colour, lipid oxidation, cooking weight loss and shear force on days 1, 4, 7 and 14 of shelf-life, in samples preserved at -20 °C. In addition, the long chain fatty acid profile was analysed. A completely randomised design was used, and the means were compared with Tukey's test (P < 0.05). The mean lightness (L*), yellowness (b*) and hue (H*) values were higher for T3 and T4. The addition of CT did not affect (P > 0.05) redness (a*), cooking weight loss (CWL) or shear force (SF). T4 decreased (P < 0.05) stearic acid and increased cis-9 trans-12 conjugated linoleic acid (CLA). Bioaccessibility was higher in the supplemented groups (T1 < T2, T3 and T4). In conclusion, supplementing CT from AME in the diet of lambs did not reduce lipid oxidation, but T3 or T4 improved some aspects of meat colour and CLA deposition.

Enhancing Milk Quality and Antioxidant Status in Lactating Dairy Goats through the Dietary Incorporation of Purple Napier Grass Silage

Oxidative stress resulting from an imbalance between oxidants and antioxidants can cause damage to certain cellular components. Purple Napier grass, a semi-dwarf variety, is characterized by its purple leaves and contains anthocyanins, which provide it with antioxidant properties. This study examined the effects of feeding purple Napier grass ("Prince") silage to lactating dairy goats on blood antioxidant activity, milk yield, and milk quality. Eighteen female Saanen crossbred goats, weighing 52.34 ± 2.86 kg and producing milk for 14 ± 2 days, were systematically divided into three groups based on their lactation period in the previous cycle as follows: early, mid, and late lactation. In a randomized complete block design (RCBD), treatments were randomly allocated to six animals in each block. The dairy goats were fed a total mixed ration (TMR) consisting of the three following treatments: control (100% Napier Pakchong 1 grass silage), 50% (a 50% replacement of the control with purple Napier grass silage), and 100% (100% purple Napier grass silage). The results show that goats who were fed a diet including 100% purple Napier grass silage showed higher levels of certain milk contents, especially with regard to lactose, when compared to those who were fed a control diet, as well as a diet with a 50% replacement of purple Napier grass silage. The somatic cell count (SCC) of these goats was reduced. In terms of antioxidant activity, dairy goats who were fed 100% purple Napier grass silage showed higher levels of enzymes in both plasma and milk, including glutathione s-transferase, total antioxidant capacity, superoxide dismutase, and 2,2-diphenyl-1-picrylhydrazyl radical, compared to the control group and the 50% replacement group. The plasma and milk of these goats showed lower levels of malondialdehyde. The dairy goats who were fed a 100% purple Napier grass silage diet showed higher concentrations of anthocyanins, including C3G, P3G, Peo3G, M3G, Cya, Pel, and total anthocyanins in milk, when compared to the control group and the 50% replacement group. The increased replacement of purple Napier grass silage led to significant differences in lactose levels, somatic cell count, glutathione S-transferase, total antioxidant capacity, superoxide dismutase, 2,2-diphenyl-1-picrylhydrazyl radical, and the composition of anthocyanins. This study provides evidence to support the use of purple Napier grass silage as a beneficial source of roughage for lactating dairy goats.

Improved muscle fatty acid composition and oxidative stability in lambs grazing on sainfoin pasture

As a mode of animal management, grazing on pasture has the potential to improve animal performance and provide healthy meat. However, there is little information about the effects of lamb meat quality grazed on sainfoin pasture. Therefore, the present study was conducted to compare the fatty acid composition and oxidative stability of growing lambs. The twenty-four lambs were randomly divided into grazing on sainfoin pasture (GS) or feeding indoors pelleted total mixed ration (FI). The results show that GS had the higher polyunsaturated fatty acids (PUFA), especially n-3 PUFA (P = 0.002), and beneficial for nutritional index of fatty acid. Corresponding that GS had lower the Thiobarbituric acid reactive substance (TBARS) in raw (P = 0.005) and cooked meat (P = 0.008). The GS had higher total phenols (P = 0.021), ferric reducing antioxidant power (FRAP) (P = 0.048) and α-Tocopherol of meat (P = 0.004). In conclusion, grazing on sainfoin pasture in lambs can improve muscle fatty acid composition and oxidative stability than feeding indoors.

Trade-offs between selection of crude protein and tannins in growing lambs

Tannins are phenolic compounds that provide benefits to ruminants due to their protein-binding affinities and antioxidant properties. However, tannins may also have negative orosensorial and postingestive effects that decrease feed intake. This study explored how lambs trade off the ingestion of crude protein (CP) with the ingestion of potentially beneficial and toxic condensed and hydrolyzable tannins, and the ensuing impacts on diet digestibility, animal performance, and blood parameters. Thirty-two lambs were housed in individual pens for 8 wk and had access to 2 isoenergetic diets that varied in the concentration of CP (High-high in protein [HP] or Low-least preferred [LP]) and the presence of a mix of condensed and hydrolyzable tannins (4% DM). Animals were assigned to 4 treatment groups (N = 8 lambs/group) and received a simultaneous offer of: HP and LP (Control); HP and LP + tannins (HP - LP+); HP+ tannins and LP (HP + LP-); and both HP and LP with tannins (HP + LP+). All lambs preferred HP over LP and they avoided tannins in the diets (P < 0.001). Dry matter and CP intake were the lowest in HP + LP- (P < 0.0001), and DMD did not differ between Control and the other groups (P > 0.05), but it was greater for HP - LP + (P < 0.0001). CP digestibility was greater for groups without tannins in HP (P < 0.0001), but average daily gain (ADG) did not differ among treatments (P > 0.05). No differences between Control and HP + LP + were found in plasma antioxidant activity, total phenolic concentration, or haptoglobin concentration (P > 0.05). Intake of tannins was HP + LP+ > HP + LP- > HP - LP + (P < 0.0001), and fecal excretion of nitrogen (N) was HP + LP+ > HP - LP+ = HP + LP- > Control (P < 0.05). In addition, intake of tannins with both diets reduced blood urea nitrogen (BUN) concentration relative to Control (P < 0.05), thus suggesting a shift in the partitioning of N excretion from urine to feces. In summary, lambs prioritized the selection of HP over LP, regardless of the presence of a tannin extract in either or both diets. Nevertheless, lambs modulated their tannin consumption as a function of the specific diet where the tannin extract was added, with increasing levels of intake as tannins were present in just LP, then in just HP, and finally in both diets. Dietary tannins did not constrain ADG and resulted in a shift in the partitioning of N excretion from urine to feces. Such shifts have been found to result in reduced production of environmental pollutants such as ammonia, nitrous oxide, and nitrates.

Influence of Sex on Meat and Fat Quality from Heavy Alentejano Pigs Finished Outdoors on Commercial and High Fiber Diets

This work aimed to examine the effects of sex on meat and fat quality traits from thirty Portuguese Alentejano (AL) pigs reared in outdoor conditions. These pigs were divided into three groups and fed ad libitum. From ~40 to 130 kg LW, castrated (C group) and intact animals (I and IExp) consumed commercial diets. Until slaughter (~160 kg), C and I pigs remained on commercial diets, and IExp changed to a more sustainable experimental diet with locally produced pulses and byproducts. Samples were collected from the Longissimus lumborum (LL), Psoas major (PM), and dorsal subcutaneous fat (DSF). At ~160 kg, the PM muscle of intact pigs presented lower intramuscular fat content than that of C pigs, while total collagen was higher. Additionally, PM myoglobin was lower and lightness (L*) was higher in intact pigs. Regarding DSF, moisture and total protein contents were higher and total lipids were lower in intact than in castrated pigs, while color parameters were not significantly different. Finally, antioxidant capacity measured in the LL muscle showed an overall lower value in intact pigs. However, lipid oxidation values were not significantly different between the experimental groups and only increased with storage time. Outdoor-reared intact AL pigs produced leaner and less saturated pork and fat compared to castrated ones. Despite the lower antioxidant activity observed in the LL muscles of intact pigs, the lipid oxidative stability of cooked meat was not different among the experimental groups.

Feeding hazelnut skin to lambs delays lipid oxidation in meat

This study aimed to investigate the effect of dietary hazelnut skin (HNS), a by-product of confectionery industry, on the oxidative stability of lamb meat. Twenty-two finishing lambs were randomly assigned to 2 groups and fed ad libitum for 56 days on different concentrate-based diets: one control and one experimental, in which 150 g/kg of corn was replaced by HNS. After slaughter, the fat-soluble vitamins content and hydrophilic antioxidant capacity were assessed in fresh meat, as well as color, lipid and protein stability over 7 days of shelf-life trial. Dietary HNS increased (P < 0.001) the tocopherols content of meat and reduced (P < 0.001) lipid oxidation during 7 days of refrigerated storage. Meat from lambs fed HNS showed different (P < 0.05) instrumental color parameters. No diet effect (P > 0.05) was observed on the development of metmyoglobin, hydroperoxides, thiol groups, and carbonyl groups. Feeding HNS to lambs improves the oxidative stability of raw meat by delaying lipid oxidation thanks to the antioxidant molecules (tocopherols and phenolic compounds) contained in this by-product.

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.

The effect of dietary inclusion of Artemisia sieberi leaves on growth performance, feeding behaviors, ruminal fermentation, feed digestibility, and blood hemato-biochemical profile of growing male lambs

The objective of this study was to investigate the impacts of replacing alfalfa hay with Artemisia sieberi leaves (ASL) on growth performance, feeding behaviors, total tract feed digestibility, ruminal fermentation as well as blood cells, and biochemical parameters. A total of 21 Kermani male lambs (average body weight (BW) of 25.2 ± 0.9 kg) were randomly divided into three groups and offered the following treatments: (1) basal diet (65% concentrate and 35% alfalfa hay as forage source), (2) ASL inclusion at 25% of forage source (8.75% of TMR, ASL25), and (3) ASL addition at 50% of forage source (17.5% of TMR, ASL50). The experiment lasted for 64 days, including 14 days of adaptation and 50 days of data collection. Dietary ASL inclusion decreased lambs' feed consumption (6.7 and 2.8% reduction in ASL25 and ASL50, respectively, p < 0.05) without affecting water intake, final BW, daily weight gain, and feed conversion ratio. Moreover, feeding behaviors, including time spent for eating, ruminating, and chewing activities, were uninfluenced by the dietary ASL addition on days 25 and 50 of the experiment. Based on the data provided, the substitution of alfalfa hay with ASL resulted in an increase in the digestibility of dry matter, organic matter, and neutral detergent fiber (p < 0.05). In addition, the ruminal fluid of ASL-fed lambs had a lower molar proportion of acetate and a higher proportion of propionate compared to that of the control animals (p < 0.05), whereas other volatile fatty acids (VFA) and total VFA were not different between the experimental groups. Blood hematocrit, hemoglobin, red cells, white cells, and their differentiation, platelets, glucose, total protein, albumin, globulin, triglyceride, calcium, phosphorus, aspartate aminotransferase, and alanine aminotransferase, urea, total antioxidant capacity, and malondialdehyde remained unchanged when ASL was included in the diet. Regardless of the slight decrease in dry matter intake, the lack of adverse effects of dietary ASL addition on growth performance, feeding behaviors, rumen fermentation, and blood hemato-biochemical parameters, along with positive impacts of ASL on propionate production and total tract feed digestibility, suggest that Artemisia sieberi leaves can be considered as a potential alternative feed resource for small ruminants.

Effect of Feeding System on Muscle Fiber Composition, Antioxidant Capacity, and Nutritional and Organoleptic Traits of Goat Meat

The objective of this study was to evaluate the effect of feeding system on muscle fiber composition, antioxidant capacity, and nutritional and organoleptic traits of goat meat. Goats that grazed on flatland (whole area with about 0% inclination, FG group) and mountain range (whole area with about 40% inclination, MG group) were selected for the analysis. The results showed that grazing on flatland increased oxidized-twitch fiber percentage, the expression of the MyHC IIa gene (p < 0.001), the activity of glutathione peroxidase (GSH-Px) (p < 0.05), total antioxidant capacity (T-AOC) (p = 0.001), and radical scavenging ability (RSA) (p < 0.05); meanwhile, the MyHC IIb gene expression (p < 0.01) and malondialdehyde (MDA) content (p = 0.001) were decreased. Feeding system affected nutritional and organoleptic traits of goat meat, and grazing on flatland increased protein content, total content of monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA), pH45min, a* value, and variety of volatile flavor compounds but decreased the content of saturated fatty acid (SFA), shear force, and b* value. In addition, the key flavor substances were screened using relative odor activity value (ROAV), including hexanal, heptanal, (E)-2-octenal, octanal, nonanal, decanal, (E)-2-nonenal, and 1-octen-3-ol. Among them, 1-octen-3-ol and (E)-2-nonenal were the most contributing flavor compounds in the FG and MG groups, respectively, providing distinctive odor to goat meat.

The Quality of Salted Sun-Dried Meat from Young Nellore Bulls Fed Diets with Lauric Acid

This study aims to evaluate the quality of salted sun-dried meat from young bulls (Nellore cattle) fed with a diet containing 0.0, 0.5, 1.0 and 1.5% of lauric acid in the total dry matter (DM). Thirty-two Nellore bulls with initial body weight of 368 ± 32 kg were used. A linear decrease (p < 0.05) in pH and protein content of the salted sun-dried meat was observed with the inclusion of lauric acid. The moisture, ash, lipid, collagen content, water-holding capacity, cooking loss, color indexes (L*, a*, b*, C*), and shear force were not affected. Lipid oxidation at 7 days of storage increased linearly in the salted sun-dried meat. Most of the fatty acid composition of the salted sun-dried meat from the semimembranosus muscle of young bulls was not influenced (p > 0.05) by the lauric acid inclusion in the bulls’ diet. However, there was a linear increase (p < 0.05) in the SFA lauric acid (C12:0), PUFAn-3 EPA (C20:5n − 3) and DHA (C22:6n − 3), and a quadratic increase in the PUFAn-6 arachidonic (C20:4n − 6) due to lauric acid addition from palm kernel oil in the diet. There was a liner increase (p < 0.05) in the total ∑PUFA, ∑n − 6, ∑n − 3 contents of salted sun-dried meat from the semimembranosus muscle of young bulls and the h:H health index of the level of lauric acid inclusion in bull’s diet. In contrast, the thrombogenicity health index (TI) and ∑n − 6:∑n − 3 ratio content in salted sun-dried meat from the semimembranosus muscle of young bulls presented a linear decrease (p < 0.05) due to lauric acid addition in the bulls’ diet. Lauric acid (C12:0) inclusion up to 1.5% in the diet of young Nellore bull improved the fatty acid composition of the salted sun-dried meat, increasing EPA, DHA, n − 6 and n − 3, TI, and h:H indexes, which are associated with a better lipid quality of meat products, and further improves tenderness at the highest concentration.

Effects of Cherry (Prunus cerasus L.) Powder Addition on the Physicochemical Properties and Oxidation Stability of Jiangsu-Type Sausage during Refrigerated Storage

Effects of different levels (1%, 3% and 5%) of cherry powder on the physiochemical properties and antioxidant activity of Jiangsu-type sausages were investigated at 4 °C for 30 days. The results show that the sensory evaluation values and physicochemical properties of the sausages had no significant differences compared to the control group when cherry powder addition was 1%, and the alcohols, aldehydes and esters were increased after the addition of cherry powder improved the flavor of sausages. However, higher concentration of cherry powder (3% and 5%) exerted adverse influences on sensory evaluation values and physicochemical properties of sausages compared with the control. The addition of cherry powder could better inhibit lipid and protein oxidation of sausages, and the cherry powder concentration has a positive correlation with its effect on the inhibition of lipid and protein oxidation. In addition, cherry powder could effectively control TVB-N values of sausages during chilled storage. All these results indicate that 1% cherry powder could not only guarantee the physicochemical properties of sausages, but also inhibited the oxidation of sausages during chilled storage.

Feeding tannins to dairy cows in different seasons improves the oxidative status of blood plasma and the antioxidant capacity of cheese

The aim of the present study was to assess the dietary supplementation of tannins to grazing dairy cows in 2 seasons characterized by a good quality pasture (spring) or a poor-quality pasture (summer). The effects of dietary tannins were assessed on plasma antioxidant status and cytokines profile and on the antioxidant properties of cheese and cheese in vitro digestates. Fourteen lactating dairy cows were divided into 2 homogeneous groups (n = 7): a control group (CON), and an experimental group (TAN) receiving 150 g/head per day of tannins supplementation. The experiment was performed twice, in spring and in summer. The animals were free to graze on spontaneous pasture (spring) or on dry stubble (summer). Blood was sampled at the beginning (d 0), at the midpoint (d 11), and at the end (d 22) of the trial. Individual cheese was produced before the beginning (d -1) and at the end (d 22) of the trial from the milk collected from each cow. On blood plasma, the reactive oxygen metabolites (ROM), biological antioxidant potential (BAP), nonesterified fatty acids quantification, and cytokines profile in terms of IL-10, IL-8, IL-1β, and IFN-γ were determined. Data on ROM demonstrated that tannins supplementation lowered oxidative stress both in spring and in summer. Accordingly, TAN diet increased BAP levels compared with the CON during summer trial. Thus, feeding tannins resulted in lower ratio between ROM and BAP (oxidative stress index) in both spring and summer. Cytokines' profile showed lower IL-1β values in TAN group at d 22 during spring season, with a concomitant higher IL-10 level, during summer season. Moreover, TAN group had a lower level of IFN-γ in plasma than CON group, both in spring and in summer. On cheese samples, the in vitro digestion was performed and on cheese and cheese digestates (gastric and intestinal digestate) the free radical scavenging antioxidant activity was evaluated. The intestinal digestate fraction registered the highest antioxidant activity compared with cheese and gastric digestate, in both spring and summer seasons. Furthermore, an improvement of the antioxidant property of cheese and cheese digestates was found. Present data demonstrated that tannins supplementation contributed to reduce the oxidative stress of lactating dairy cows and showed an increase of anti-inflammatory cytokines ratio.

Inclusion of Grape Pomace in Finishing Cattle Diets: Carcass Traits, Meat Quality and Fatty Acid Composition

Because of its high content of polyphenolic compounds, dietary inclusion of grape pomace (GP) in finishing cattle diet could possibly enhance product quality and the health value of beef lipids. Therefore, the aim of this study was to evaluate the effects of feeding a high amount of grape pomace in finishing cattle diets on carcass traits, product quality, and fatty acid (FA) composition of beef. Jersey × Holstein crosses (n = 24) were fed either a typical finishing diet (CON) or a finishing diet containing 58% grape pomace (DM basis; HGP). Following the feeding period, animals were harvested, and carcass traits measured. Longissimus lumborum (LL) and semimembranosus (SM) muscle were then collected from each carcass for sensory quality evaluation and FA profile analysis. Hot carcass weight, backfat thickness, and preliminary and final yield grades were greater (p ≤ 0.04) for CON than HGP steers. However, there was no diet effect on rib eye area (REA), kidney, pelvic, and heart (KPH) fat, and marbling. Feeding the HGP compared to CON diet reduced lipid oxidation of LL and SM steaks over time; the malondialdehyde (MDA) concentration, which did not differ on d 0 and 2 of 8-d simulated retail display, was lower on d 4, 6 and 8 for HGP than CON steers (treatment × day of simulated display interaction; p < 0.01). Brightness (L* values) and redness (b*) were greater for LL steaks from HGP than CON steers on most days of simulated display (treatment × day of simulated display interaction; p < 0.01). In addition, the LL and SM muscle content of several FA linked to positive health outcomes in humans including 18:2 n-6, 18:2 c9t11, total conjugated linoleic acid (CLA) and total polyunsaturated fatty acid (PUFA) was also greater (p ≤ 0.02) for steers fed the HGP compared to the CON diet. In summary, current findings suggest that although it could possibly limit growth performance, feeding a high amount of grape pomace to finishing cattle could enhance both the sensory quality and the health value of beef lipids, which are key in increasing consumer acceptability of beef.

Influence of almond hulls in lamb diets on animal performance and meat quality

Almond hulls (AH) were fed to lambs to study effects on performance and meat quality. Thirty Sarda lambs were allotted to three experimental groups and fed for 40 days either a cereal-based concentrate diet (control) or diets in which cereals were replaced with 15% (AH15) or 30% (AH30) almond hulls on a DM basis. Diets did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio or carcass weight. Replacing part of the cereal mix (i.e., barley and maize) with AH did not affect meat fatty acid profiles. After 5 and 7 days of refrigerated storage respectively for cooked and raw meat, AH15 and AH30 treatments reduced meat lipid oxidation (P < 0.001). Our results suggest feeding almond hulls up to 30% in fattening lamb diets can improve meat oxidative stability without compromising growth performance.

Influence of Dietary Inclusion of Exhausted Bergamot By-Product in Pigs on Animal Performance, Fatty Acid Profile and Oxidative Stability of Meat and Meat Products

An investigation was carried out on the effect in pig diet of supplementation with exhausted bergamot by-product, stemming from pharmaceutical industry after extraction of phenolic compounds, on growth performance and on the quality of meat and meat products. Twenty pigs were assigned to two dietary treatments and fed a conventional concentrate (control) or a concentrate including exhausted bergamot by-product at the level of 15% on a DM basis (EB). No significant differences between dietary treatments were found for final weight (p = 0.243), carcass weight (p = 0.679), dry matter intake (p = 0.321). In EB pork, the proportion of docosapentaenoic acid was significantly increased (p < 0.05); it tended to have a greater proportion of n-3 PUFA (p = 0.09), and the n-6/n-3 PUFA ratio was lower in EB treatment (p = 0.01). In salami from EB pigs fed, the proportion of α-linolenic acid and the total n-3 PUFA were higher than in the control group (p < 0.001). In salami, the TBARS value was lower after 5 days of storage (p < 0.001) in the EB group. Therefore, the present results suggest that the inclusion of exhausted bergamot by-product in pig diet resulted in a qualitative improvement of meat and meat products.

Insights into the role of major bioactive dietary nutrients in lamb meat quality: a review

Feed supplementation with α-linolenic acid (ALA) and linoleic acid (LA) increases their content in muscle, ALA increases n-3 polyunsaturated fatty acids and decrease n-6/n-3 ratio in muscle, and LA increases rumenic acid. However, high LA supplementation may have negative effects on lambs’ lipid oxidative stability of meat. When the sources of ALA and LA are fed as fresh forage, the negative effects are counterbalanced by the presence of other bioactive compounds, as vitamin E (mainly α-tocopherol) and polyphenols, which delay the lipid oxidation in meat. There is a wide consensus on the capability of vitamin E delaying lipid oxidation on lamb meat, and its feed content should be adjusted to the length of supplementation. A high dietary inclusion of proanthocyanidins, phenolic compounds and terpenes reduce the lipid oxidation in muscle and may improve the shelf life of meat, probably as a result of a combined effect with dietary vitamin E. However, the recommended dietary inclusion levels depend on the polyphenol type and concentration and antioxidant capacity of the feedstuffs, which cannot be compared easily because no routine analytical grading methods are yet available. Unless phenolic compounds content in dietary ingredients/supplements for lambs are reported, no specific association with animal physiology responses may be established.

Biological Function of Plant Tannin and Its Application in Animal Health

Plant tannins are widely found in plants and can be divided into hydrolyzed tannins and condensed tannins. In recent years, researchers have become more and more interested in using tannin-rich plants and plant extracts in ruminant diets to improve the quality of animal products. Some research results show that plant tannins can effectively improve the quality of meat and milk, and enhance the oxidative stability of the product. In this paper, the classification and extraction sources of plant tannins are reviewed, as well as the biological functions of plant tannins in animals. The antioxidant function of plant tannins is discussed, and the influence of their structure on antioxidation is analyzed. The effects of plant tannins against pathogenic bacteria and the mechanism of action are discussed, and the relationship between antibacterial action and antioxidant action is analyzed. The inhibitory effect of plant tannins on many kinds of pathogenic viruses and their action pathways are discussed, as are the antiparasitic properties of plant tannins. The anti-inflammatory action of tannins and its mechanism are analyzed. The function of plant tannins in antidiarrheal action and its influencing factors are discussed. In addition, the effects of plant tannins as feed additives on animals and the influencing factors are reviewed in this paper to provide a reference for further research.

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.

Biopreservative efficacy of grape (Vitis vinifera) and clementine mandarin orange (Citrus reticulata) by-product extracts in raw ground beef patties

Beef patties were treated with 450 μg/g of extracts from grape (Vitis vinifera) seeds (GSE), pomace (GPE) or orange (Citrus reticulata) pomace (OPE) and compared to negative (no extract; CTR) and positive (sodium metabisulphite; SMB) controls for their effect on colour, lipid and protein oxidation and bacterial growth under simulated retail display conditions (4 °C) for 9 d, and sensory quality. Antioxidant activity and redness of beef patties increased in the order of CTR < OPE = GPE < GSE < SMB. The order of thiobarbituric acid reactive substances and carbonyl values were CTR > GPE = OPE > GSE > SBM, while that of bacterial counts were CTR > GSE = GPE > OPE > SMB. Retail display period had significant effect on all the shelf-life parameters. Overall, intensity of aroma, beef-like aroma and flavour in beef patties were highest in OPE. Results suggested that GSE and OPE could be commercially valorised as natural antioxidants and antibacterials in beef patties, respectively.

Effect of alfalfa (Medicago sativa L.) saponins on meat color and myoglobin reduction status in the longissimus thoracis muscle of growing lambs

The effect of alfalfa saponins (AS) supplementation on the meat quality especially the color for growing lamb was investigated. Fifty Hu male lambs with body weights (BW, 19.21 ± 0.45 kg) were divided into five groups and supplemented AS with 0, 500, 1,000, 2,000, and 4,000 mg/kg of dietary dry matter intake. After 90 days, all lambs were slaughtered. The longissimus thoracis muscle in lamb displayed significant changes in the content of intramuscular fat, especially n-3 polyunsaturated fatty acids, and drip loss within AS treatment (p < .05) between control and treatments groups. Redness (a*) significantly improved in both 0-day and 7-day storage with the AS supplementation coupled with the percentage of met-myoglobin reduction (p < .05). The redness (a*) change may result from improved met-myoglobin reducing activity, antioxidant enzymes, lactate dehydrogenase, and succinate dehydrogenase (p < .05) by AS supplementation in muscle. These enzymes may help to protect mitochondria function and reduce met-myoglobin, which bring a bright and red meat color.

Animal Design Through Functional Dietary Diversity for Future Productive Landscapes

Pastoral livestock production systems are facing considerable societal pressure to reduce environmental impact, enhance animal welfare, and promote product integrity, while maintaining or increasing system profitability. Design theory is the conscious tailoring of a system for a specific or set of purposes. Then, animals—as biological systems nested in grazing environments—can be designed in order to achieve multi-faceted goals. We argue that phytochemical rich diets through dietary taxonomical diversity can be used as a design tool for both current animal product integrity and to develop future multipurpose animals. Through conscious choice, animals offered a diverse array of plants tailor a diet, which better meets their individual requirements for nutrients, pharmaceuticals, and prophylactics. Phytochemical rich diets with diverse arrangements of plant secondary compounds also reduce environmental impacts of grazing animals by manipulating the use of C and N, thereby reducing methane production and excretion of N. Subsequently functional dietary diversity (FDD), as opposed to dietary monotony, offers better nourishment, health benefits and hedonic value (positive reward increasing “liking” of feed), as well as the opportunity for individualism; and thereby eudaimonic well-being. Moreover, phytochemical rich diets with diverse arrangements of plant secondary compounds may translate in animal products with similar richness, enhancing consumer human health and well-being. Functional dietary diversity also allows us to design future animals. Dietary exposure begins in utero, continues through mothers' milk, and carries on in early-life experiences, influencing dietary preferences later in life. More specifically, in utero exposure to specific flavors cause epigenetic changes that alter morphological and physiological mechanisms that influence future “wanting,” “liking” and learning of particular foods and foodscapes. In this context, we argue that in utero and early life exposure to designed flavors of future multifunctional foodscapes allow us to graze future ruminants with enhanced multiple ecosystem services. Collectively, the strategic use of FDD allows us to “create” animals and their products for immediate and future food, health, and wealth. Finally, implementing design theory provides a link between our thoughtscape (i.e., the use of FDD as design) to future landscapes, which provides a beneficial foodscape to the animals, an subsequently to us.

Effects of Algae Meal Supplementation in Feedlot Lambs with Competent Reticular Groove Reflex on Growth Performance, Carcass Traits and Meat Characteristics

There is growing interest in increasing omega-3 fatty acid (FA) contents in ruminant meat by means of dietary manipulation, but the effects of such manipulation on productive results and meat quality need to be ascertained. The aim of the present study was to assess the effects of supplementing lambs with competent reticular groove reflex (RGR) with marine algae as a source of omega-3 fatty acids on growth performance, carcass traits, and meat quality characteristics. Forty-eight feedlot lambs were distributed into three equal groups: the control group neither consumed marine algae nor had competent RGR, the second group received daily 2.5% of algae meal mixed in the concentrate, and the last group consumed the same amount of algae meal, but emulsified in a milk replacer and bottle-fed. Lambs in the second and third groups had competent RGR. There were not any negative effects on performance, carcass or meat quality parameters with algae supplementation. However, the results of the oxidative stability parameters were not conclusive. Ageing for 6 days improved meat tenderness and color, and increased lipid oxidation. In conclusion, algae meal inclusion in the diet of fattening lambs with competent RGR has no detrimental effects on animal performance, carcass traits or meat quality characteristics.

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 Astragalus Membranaceus supplementation on oxidative stability of Cashmere goat

Astragalus membranaceus (AM) provides a rich source of polysaccharides that can act as powerful antioxidants, but their potential as feed ingredients in the lamb industry still rarely exploited. The objective of this study was to investigate the effect of dietary astragalus membranaceus supplementation on oxidative stability of goat muscles. Longissimus dorsi (LD) muscles from two groups of Cashmere goat (basal diet, C group; basal diet supplemented with 1% astragalus membranaceus root, AM group) were evaluated for lipid oxidation, myoglobin oxidation, activity of antioxidant enzymes, and antioxidant capacity. The results showed that color parameters in Cashmere goat of two feeding conditions were no significant difference (p > .05). In AM group, myoglobin (Mb) content was higher than C, while metmyoglobin (MMb) (p < .05) and malondialdehyde (MDA) (p < .01) were lower. Additionally astragalus membranaceus supplementation had a significant effect on superoxide dismutase (SOD) and catalase (CAT) (p < .001). In whole, the AM group goats presented a relatively higher antioxidant capacity than C. Especially, RSA and CUPRAC values of AM group goats had significantly higher than C (p < .05). Consequently, the AM group goats ingested abundant astragalus membranaceus, which enhanced the antioxidant capacity. Thus, it can eliminate free radicals and effectively inhibit oxidation.

Dietary supplementation of plant bioactive-enriched aniseed straw and eucalyptus leaves modulates tissue fatty acid profile and nuggets quality of lambs

Utilization of low-input feed resources rich in plant bioactive compounds is a promising strategy for modulating the fatty acid profile in ruminant products. They manipulate microbes involved in rumen biohydrogenation and increase the accumulation of desirable fatty acids at the tissue level. Therefore, the present study was undertaken to assess the effect of dietary supplementation of aniseed straw and eucalyptus leaves on growth performance, carcass traits and fatty acid profile of finisher lambs. Thirty-six Malpura hogget were divided into three treatment groups of 12 each, reared individually in pen (1.6 m × 1.1 m) and fed ad libitum complete feed blocks made up of 55 parts concentrate, 5 parts molasses and 40 parts roughage. Roughage in control (Con) was 20 parts each of ardu (Ailanthus excelsa) leaves and oat (Avena sativa) straw. In test diets, that is, Con-as and Con-el, 10% aniseed (Pimpinella anisum) straw and Eucalyptus rudis leaves, respectively, were added by replacing 5% each of oat straw and eucalyptus leaves. The lambs were weighed weekly; and at the end of 3 months of feeding trial, the lambs were slaughtered to study the carcass traits, composition and product evaluation. Average daily gain (ADG) and DM intake (DMI) was higher (P < 0.05) in Con-as compared to Con and Con-el, while ADG and feed conversion ratio decreased (P < 0.05) by 29.4% and 36.4%, respectively, in Con-el compared to Con. Carcass traits showed lower (P < 0.05) loin eye area and chilling loss in the Con-el group compared to the Con-as and Con, and the total carcass fat compared to Con-as. However, the keeping quality of meat improved in both Con-as and Con-el which was reflected by lower (P < 0.05) thiobarbituric acid-reactive substances values. Nuggets prepared from Con and Con-as meat had superior (P < 0.05) sensory attributes with an overall palatability. Fatty acid profile of longissimus thoracis muscle showed lower (P < 0.05) atherogenic and thrombogenic indices in Con-as and higher (P < 0.05) in Con-el group. Moreover, in Con-as group, the proportion of C16:0 was lower (P < 0.05) and C18:3n-3 was higher (P < 0.05), but no effect was observed on the amount of conjugated linoleic acid (CLA; C18:2 c9t11). In case of adipose tissue, the content of CLA was higher (P < 0.05), and the ratio of n-6:n-3 was more nearer to desirable levels in Con-as group. Therefore, it can be concluded that aniseed straw is a promising feed supplement compared to eucalyptus leaves for improving meat quality and fatty acid profile in lambs.

Natural Phenolic Compounds for the Control of Oxidation, Bacterial Spoilage, and Foodborne Pathogens in Meat

Alternative technologies for long-term preservation, quality assurance, and safety of meat are continuously pursued by the food industry to satisfy the demands of modern consumers for nutritious and healthy meat-based products. Naturally occurring phenolic compounds are considered promising substances by the meat industry for their antioxidant and antimicrobial properties, while consumers seem to embrace them for their claimed health benefits. Despite the numerous in vitro and in situ studies demonstrating their beneficial effects against meat oxidation, spoilage, and foodborne pathogens, wide application and commercialization has not been yet achieved. Major obstacles are still the scarcity of legislative framework, the large variety of meat-based products and targeted pathogens, the limited number of case-specific application protocols and the questionable universal efficiency of the applied ones. The objectives of the present review are i) to summarize the current knowledge about the applications of naturally occurring phenols in meat and meat-based products, emphasizing the mechanisms, determinants, and spectrum of their antioxidant and antimicrobial activity; ii) to present state-of-the-art technologies utilized for the application of phenolic compounds in meat systems; and iii) to discuss relevant regulation, limitations, perspectives, and future challenges for their mass industrial use.

How Dietary Diversity Enhances Hedonic and Eudaimonic Well-Being in Grazing Ruminants

Ruminants evolved in diverse landscapes of which they utilized, by choice, a diverse arrangement of plants (grasses, forbs, and trees) for food. These plants provide them with both primary (carbohydrates, protein, etc.) and secondary (phenolics, terpenes, etc.) compounds (PPC and PSC, respectively). As no one plant could possibly constitute a “balanced-diet,” ruminants mix diets so that they can exploit arrangements of PPC to meet their individual requirements. Diet mixing also allows for ruminants to ingest PSC at levels, acquiring their benefits such as antioxidants and reduced gastrointestinal parasites, without overstepping thresholds of toxicity. Meeting dietary requirements is assumed to provide satisfaction through achieving positive internal status and comfort, thereby a sense of hedonic (happiness through pleasure) well-being. Furthermore, choice including dietary choice is a factor influencing well-being of ruminants in a manner akin to that in humans. Choice may facilitate eudaimonic (happiness through pursuit of purpose) well-being in livestock. Nutritional status plays an integral role in oxidative stress, which is linked with illness. Several diseases in livestock have been directly linked to oxidative stress. Mastitis, metritis, hypocalcaemia, and retained placenta occur in animals transitioning from dry to lactating and have been linked to oxidative stress and such a stress has likewise been linked to diseases that occur in growing livestock as well, such as bovine respiratory disease. The link between physiological stress and oxidative stress is not well-defined in livestock but is evident in humans. As dietary diversity allows animals to select more adequately balanced diets (improved nutrition), take advantage of PSC (natural antioxidants), and allows for choice (improved animal well-being) there is a strong possibility for ruminants to improve their oxidative status and thus health, well-being, and therefor production. The purposes of this review are to first, provide an introduction to oxidative and physiological stress, and nutritional status as effected by dietary diversity, with special attention to providing support and on answering the “how.” Second, to provide evidence of how these stresses are connected and influence each other, and finally discuss how dietary diversity provides a beneficial link to all three and enhances both eudaimonic and hedonic well-being.

Black Wattle (Acacia mearnsii) Condensed Tannins as Feed Additives to Lactating Dairy Cows

Simple Summary

Plant compounds such as condensed tannins can be used to modulate ruminal fermentation, and to improve feed utilization and the final product quality in dairy cattle. In this study, we evaluated the inclusion of condensed tannins from Black Wattle (Acacia mearnsii) at levels up to 2% of the dry matter in the diets of dairy cows and its effects on feed intake, nutrient digestibility, milk production and composition. Condensed tannin inclusion in the diets did not affect feed or nutrient intake. Digestibility of diet dry matter and neutral detergent fiber was highest at inclusion levels of 1.22% and 1.14%, respectively. There was no effect of tannin inclusion on milk production; however, there was a reduction in milk casein concentration.

Abstract

The objective of this study was to evaluate the effects of five levels of condensed tannins (CT) from black wattle (Acacia mearnsii) in the diets of lactating dairy cows on intake, nutrient digestibility, ruminal microbial protein synthesis, milk production, composition, oxidative profile, and blood metabolites. Five Holstein cows (88 ± 26.8 days in milk) were allocated in a 5 x 5 Latin square design for a period of 20 days (14 days of diet adaptation and six for sampling). Treatments were the inclusion levels of CT at 0, 5, 10, 15 and 20 g/kg of dry matter (DM) in the diet. There was no effect of CT on DM intake. The digestibility of DM and neutral detergent fiber changed quadratically, with the maximum values at 12.2 and 11.4 g/kg of DM, respectively. There was no effect on ruminal microbial protein synthesis and milk production; however, milk casein concentration was reduced linearly. There was no effect on the milk oxidative profile. Inclusion of CT at levels up to 20 g/kg of DM did not affect intake or microbial protein synthesis; however, added CT depressed the production of energy corrected milk and milk casein concentration.

The impact of dietary supplementation with guava (Psidium guajava L.) agroindustrial waste on growth performance and meat quality of lambs

The aim of this study was to evaluate the growth performance and meat quality of lambs (40 animals) fed with increasing levels (0; 7.5; 15.0; 22.5 and 30.0%) of guava agroindustrial waste (GAW). The pH, cooking loss, colour and chemical composition were measured in the Longissimus lumborum (LL) muscle. A sensory analysis was performed with a panel of eight trained testers using a quantitative descriptive method in order to define sensory descriptors and their intensities. The lambs obtained a mean weight gain of 316 g/day consuming 1.32 kg/day of dry matter. The inclusion of GAW in the diet of lambs did not affect pH, L*, a* and b*. However, significant difference (P < .05) among the treatments were obtained for the chemical composition of LL: moisture decreased, while ash increased and intramuscular fat increased until 15% and then decreased at 22.5% with the inclusion of GAW. However, the sensorial characteristics of lamb meat (lamb odour and flavour, tenderness and juiciness) were not affect by the inclusion of GAW. Therefore, GAW can be included up to 30% in lamb feed without compromising the performance, physic-chemical and sensory characteristics of meat.

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

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

Technological Application of Tannin-Based Extracts

Tannins are polyphenolic compounds naturally found in vegetables. Their presence in nature has prompted their historical use in many different ways. The revision of their traditional utilization has allowed their further modification aiming for an industrial application. Sometimes these modifications have implied the addition of harmful substances such as formaldehyde, classified as a carcinogen of category B1. In other cases, these natural tannins have been replaced by synthetic compounds that threaten human and animal health and damage the environment. Therefore, currently, both academy and industry are searching for the substitution of these unsafe complexes by the increasing inclusion of tannins, natural molecules that can be obtained from several and diverse renewable resources, modified using harmless additives. To achieve promising results, cost-efficient and eco-friendly extraction methods have been designed. Once these green alternatives have been isolated, they have been successfully applied to many fields with very assorted aims of utilization such as coagulants, adhesives, floatation agents, tannings, dyes, additives, or biomolecules. Therefore, this review offers a global vision of the full process that involves the tannin’s technological application including an overview of the most relevant tannin sources, effective extraction methods, and their utilization in very diverse fields.

Wine grape pomace flour in broiler diets effects growth and some meat characteristics

Context Grape pomace maybe useful in broiler diets as a source of low cost antioxidants. Aims The objective of this work was to determine the effect of including high concentrations of wine-grape pomace flour (WGPF) in broiler chicken diets on productive parameters and antioxidant capacity of the meat. Methods WGPF of white (WGPF-W) and red (WGPF-R) grape varieties were nutritionally and chemically characterised. Then, 120 broiler chickens were allocated to three isoenergetic and isoproteic feeding treatments: 0% WGPF (Control), 20% WGPF-W and 20% WGPF-R. Key results WGPF-W had no effect on bodyweight, daily weight gain, feed intake or feed conversion ratio (FCR). However, FCR was higher for WGPF-R treatment at the end of the study (Day 42). Meanwhile, breast meat from WGPF-R treatment had the highest content of ether extract (P &lt; 0,05), followed by WGPF-W and by control treatment, due to the addition of higher amounts of soy oil to those diets with WGPF to ensure an isoenergetic composition. Breast and leg meat, respectively, showed greater antioxidant capacity (µM Trolox Eq/g) when WGPF-W (16.7 and 16.4) was fed, than the antioxidant capacity obtained for control (13.8 and 13.8) and WGPF-R (11.9 and 14.2) treatments. Conclusions Inclusion of 20% of WGPF-W increased antioxidant capacity of chicken meat by 17%, without decreasing productive parameters, provided the diets were made isoenergetic and isoproteic by adding soy oil. Implications The grape pomace flour could be useful in the diet of other animals.

Meat Production from Dairy Breed Lambs Due to Slaughter Age and Feeding Plan Based on Wheat Bran

Simple Summary

The sheep meat sector in southern Italy, based mainly on light milk-fed lambs, requires technical innovations to improve the production system, the product quality, and enhance the consumption of lamb meat. To fulfill these requirements, this investigation aimed to implement feeding strategies to reduce the cost and energy level of diets for dairy breed lambs slaughtered at an older age than the light lambs, applying a feed restriction at 75% and/or including an inexpensive and local byproduct, such as durum wheat bran (DWB), as a fiber source. The proposed feeding plans were suitable to increase the slaughter age of lambs up to 120 days and produce lean carcasses that, compared to those from 90-day-old lambs, were heavier and with improved meat quality in terms of major water retention and tenderness. The dietary inclusion of DWB limited the fat content and improved the health properties of lamb meat with regard to its antioxidant capacity and fatty acid profile, whereas it reduced lambs’ growth when associated with feed restriction.

Abstract

This experiment aimed to investigate the possibility to increase the carcass weight of dairy breed lambs and produce moderate-fat meat by applying inexpensive feeding strategies based on restriction and through the use of a fibrous byproduct such as the durum wheat bran (DWB). Sixty-five 45-day-old lambs of the Valle del Belice breed, divided into 6 groups, were fed alfalfa hay supplemented with concentrate feeds including DWB at 0% or 20% (DWB0, DWB20), supplied ad libitum (L) or restricted at 75% (R), and slaughtered at 90 or 120 days of age. The groups were as follows: DWB0-90L (n = 14), DWB20-90L (n = 14), DWB0-120R (n = 10), DWB20-120R (n = 9), DWB0-120L (n = 9), DWB20-120L (n = 9). The diet did not affect feed intake, growth or carcass weight of lambs fed ad libitum, whereas 120-day-old lambs fed DWB associated to restriction showed the lowest weight gain (105 vs. 170, 185 and 190 g/day in DWD20-120R, DWB0-120R, DWB0-120L and DWB20-120L; p = 0.04). The incidence of fat tissue in the hind leg increased (p < 0.0001) from 90L (5.82 and 5.45% with DWB0 and DWB20) to 120R (8.80 and 8.43% with DWB0 and DWB20) and 120L lambs (10.7 and 11.8% with DWB0 and DWB20). Older lambs’ meat, compared to that of 90L lambs, showed analogous levels of intramuscular fat, higher water retention, tenderness and lightness, and a more intense red colour. In meat from 120-day-old lambs, DWB intake tended to reduce the fat level (p = 0.009) and increased polyphenol content (1.10 vs. 1.62, and 1.02 vs. 1.65 g GAE/kg dry matter (DM) in 120R and 120L lambs; p = 0.02), antioxidant capacity (12.8 vs. 14.9, and 12.8 vs. 15.7 mmol trolox eq/kg DM in 120R and 120L lambs; p = 0.02), and the presence of n-3 polyunsaturated fatty acids (FA) (1.61 vs. 2.81, and 1.43 vs. 2.61 g/100 g FA in 120R and 120L lambs; p = 0.007), thereby improving the meat’s health properties. The panelists perceived the effects of DWB inclusion as well as the feeding level with triangle tests.

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.

Feeding lambs with silage mixtures of grass, sainfoin and red clover improves meat oxidative stability under high oxidative challenge

This study investigated the oxidative stability of meat from lambs fed silages in which timothy grass was totally or partially replaced by sainfoin and/or red clover. Five groups of 8 lambs were fed the following silages: timothy grass (T), mixture (50:50) of timothy with either sainfoin (T-SF) or red clover (T-RC), mixture of timothy, sainfoin and red clover (50:25:25; T-SF-RC), or mixture (50:50) of sainfoin and red clover (SF-RC). Feeding the silages containing red clover (T-RC, T-SF-RC and SF-RC) decreased the deposition of vitamin E in muscle relative to the highly unsaturated fatty acids (P < .001), did not affect the oxidative stability of fresh meat, but reduced oxidative deterioration in cooked meat and in meat homogenates incubated with pro-oxidant catalysts (P < .001). The results of this study demonstrated that feeding lambs with silages containing sainfoin and red clover improve the oxidative stability of meat subjected to strong pro-oxidant conditions and suggest that these effects should be further clarified.

Antioxidant capacity, lipid oxidation status and expression of specific selenoprotein mRNA in Longissimus dorsi muscle of lambs (Ovies aries) supplemented with supranutritional selenium

Selenium is known to play a key role in maintenance of redox status of tissues, immunity, reproduction, thyroid and muscle functions. The present investigation was carried out to understand the effect of supranutritional dietary Se supplementation on antioxidant capacity, lipid oxidation and expression of specific selenoprotein mRNA in Longissimus dorsi muscles of growing lambs. Twenty male lambs of 5–6 months of age were fed basal diet supplemented with 0.5, 1.5 or 4.5 ppm Se-yeast (organic Se) or without Se (control) for 90 days. The antioxidant capacity, lipid oxidation of meat during different days of storage and the mRNA expression of GPX1, GPX2, GPX3, TXNRD1, TXNRD3, DIO1, DIO2, DIO3, SEPP1, SEP15 and SEPW1 were studied in Longissimus dorsi muscles of sheep. The results indicated improvement in antioxidant status by supplementation of 1.5 and 4.5 ppm Se, and reduction in meat lipid oxidation status on day 0 without any further reduction after 3 and 7 days of storage in all the Se supplemented lambs. A selective change in expression of GPX2, GPX3, TXNRD1, DIO2, DIO3, SEPP1, SEP15 and SEPW1 mRNA was observed by supranutritional Se while GPX1, TXNRD3, DIO1 and expressions remained unaffected by supplementation. In conclusion, supranutritional Se supplementation in lambs increased antioxidant status, reduced lipid oxidation status with limited effect on oxidative stability of meat during storage and regulated Longissimus dorsi muscle selenoprotein mRNA expression differentially depending on the Se feeding levels. Our results thus provided new insights into the regulation of selenoprotein gene expression by supranutritional levels of dietary Se.

Improvement of Oxidative Status, Milk and Cheese Production, and Food Sustainability Indexes by Addition of Durum Wheat Bran to Dairy Cows' Diet

Durum wheat bran (DWB) is a by-product mostly used in feeding ruminants, contributing to decrease in the utilization of feeds suitable as foods for human consumption, thus improving the sustainability of livestock production. However, the potential benefits of DWB, due to its content in phenolic acids, mainly consisting of ferulic acid with antioxidant properties, have not been well clarified yet. Accordingly, in this experiment, 36 lactating cows divided into three groups received, over a period of 100 days, one of three concentrates including DWB at 0% (DWB0), 10% (DWB10), or 20% (DWB20). The concentrates were formulated to be isoproteic and isoenergetic and, to balance the higher fiber content of the concentrates with DWB, the hay in the diets was slightly reduced. During the trial, the group feed intake and the individual milk production were monitored, and cheese was made with bulk milk from each group. Milk yield and microbiological characteristics of milk and cheese were similar among groups, indicating no DWB effect on cows performance and fermentation process. Milk from DWB20 group resulted slightly higher in casein and curd firmness (a_2r). In cows fed DWB, the higher polyphenol intake was responsible for higher blood contents of these bioactive compounds, that seemed to have contributed in reducing the level of reactive oxygen metabolites (ROMs), which were higher in DWB0 cows. DWB20 cheeses showed a higher polyphenol content, lower number of peroxides, and higher antioxidant capacity than DWB0 cheeses. DWB20 and DWB10 diets resulted less expensive. In addition, the DWB20 group showed the best indexes heFCE (human edible feed conversion efficiency = milk/human edible feed) and NFP (net food production = milk - human edible food), expressed as crude protein or gross energy. In conclusion, the DWB fed to dairy cows at 12% of diet dry matter (DM) can lead to benefits, such as the improvement of oxidative status of cows, milk quality, shelf-life, and functional properties of cheese, and might contribute to reduce the feeding cost and limit the human-animal competition for feeding sources.

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.