Diet Of Lambs Research Articles

Peanut Cake as an Alternative Protein Source to Soybean Meal on Performance, Nitrogen Utilization, and Carcass Traits in Feedlot Lambs

Substituting soybean meal (SM) with other protein sources can be advantageous in reducing production costs without increasing nitrogen losses in the environment. Peanut cake (PC) might be a strategy in ruminant herds to result in a performance similar to that observed in animals fed SM. This study assessed the PC inclusion at rates of 0, 250, 500, 750, and 1000 g/kg on intake and digestibility, performance, nitrogen balance, microbial protein synthesis, and carcass traits of lambs. Forty-five entire, crossbreed Dorper × Santa Inês lambs (average age = five months and 24.49 ± 5.27 kg of BW) were distributed in a completely randomized design. Only the ether extract intake was not affected by the PC inclusion, and only the crude protein digestibility was affected by the diets. The total weight and average daily gains decreased, and the feed conversion increased. Hot carcass yield was influenced quadratically, the leg depth increased and the loin-eye area decreased. The total replacement of soybean meal with peanut cake in diets for lambs did not compromise nutrient digestibility, microbial protein synthesis, and carcass characteristics. Nevertheless, peanut cake as a protein source in the diet had adverse effects on nutrient intake and growth performance of feedlot lambs.

Characterization of Chestnut Tannins: Bioactive Compounds and Their Impact on Lamb Health

The objective of the present study was to characterize the chestnut (Castanea sativa Mill.) tannin product, Farmatan Plus® (Tanin Sevnica d.d., Sevnica, Slovenia), and to subsequently examine its effects on the blood metabolic parameters of fattening lambs, particularly in relation to their health status. Thirty lambs were randomly divided into three treatment groups: a control group without added tannin and two groups that received 9.46 g of the tannin product/kg of the diet dry matter (DM) and 18.87 g of the tannin product/kg of the diet DM. Metabolic parameters such as contents of total protein, globulin, urea, and liver enzymes (AST and GGT) were measured over a trial period of 60 days to evaluate the effects of tannin supplementation. This study represents the first in-depth characterization of Farmatan Plus®, demonstrating its richness in bioactive compounds such as vescalin and castalagin. The results showed no significant adverse effects on lamb health, with all parameters remaining within normal physiological ranges (p > 0.05). These results support the safe inclusion of chestnut tannins in the diet of lambs and underline their potential as a functional feed additive that can positively influence the health and growth performance of ruminants.

Growth performance and body composition of feedlot lambs fed refused melon fruit.

This study aimed to evaluate the effect of replacing corn grain with refused melon fruit (RMF) in the diet on the intake and digestibility of nutrients, performance, carcass characteristics, and physical-chemical attributes of meat from lambs finished in feedlot. We used 30 male lambs of the Santa Inês breed, not castrated, with 18.3 ± 1.1kg body weight and 120 days of life, feedlot in individual stalls for 71 days. The animals were fed at will with treatment diets containing 0g/kg (control, without RMF), 100, 200, 300, or 400g/kg of RMF in the dry matter of the total diet, in a forage: concentrate ratio of 30:70. There was a significant decrease (P < 0.05) in the intake of dry matter, neutral detergent fiber, non-fibrous carbohydrates, and metabolizable energy of the lambs receiving diets with the inclusion of RMF. The inclusion of RMF significantly decreased (P < 0.05) the final weight, average daily gain, and gross feed efficiency but did not influence (P > 0.05) the carcass weight and tissue composition of the shoulder. There was no significant effect (P > 0.05) of the inclusion of RMF on the physical-chemical characteristics of the meat, but the moisture content of the meat increased significantly (P < 0.05) with increasing RMF in the diet. We recommend including up to 300g/kg of RMF in diets for lambs formulated to gain 0.2kg/day and with a 30:70 forage: concentrate ratio.

Targeted metabolomics analysis of fatty acids in lamb meat for the authentication of paper mulberry silage as a substitute for alfalfa silage

BackgroundThe paper mulberry (Broussonetia papyrifera L.) is a valuable source of woody forage that can be used for ruminants, such as goat and lambs. However, there is limited knowledge about how paper mulberry silage affects carcass characteristics, meat physicochemical attributes, amino acid and unsaturated fatty acids in Hu lambs compared to alfalfa silage. The objective of this experiment was to investigate the impact of substituting alfalfa silage with paper mulberry silage on the slaughter performance, meat quality, free amino acid and fatty acid composition in muscles of Hu lambs.ResultsThirty 60-day-old male Hu lambs with 17.13 ± 0.26 kg body weight were randomly allocated into paper mulberry silage (30% of total mixed ration) and alfalfa silage (30% of total mixed ration) treatment, and the feeding trial lasted 70 days. The results indicated no significant differences in all measurements (P > 0.05). However, compared to the group fed with alfalfa silage, the group fed with paper mulberry silage exhibited a reduction in meat drip loss (P < 0.05) without any notable effect on meat nutrients (P > 0.05). Targeted metabolomics analysis revealed that feeding paper mulberry silage led to decreased levels of certain bitter amino acids, such as valine, leucine, isoleucine, tryptophan, and phenylalanine (P < 0.05). Furthermore, the consumption of paper mulberry silage significantly augmented the levels of monounsaturated and polyunsaturated fatty acids, particularly n6-polyunsaturated fatty acids (C18:2n6, C20:3n6, C20:4n6, etc.), in meat.ConclusionsSubstituting paper mulberry silage for alfalfa in the daily diet of Hu lambs not only has no detrimental effect on animal performance but also improves meat unsaturated fatty acid composition.Graphical

Effect of Long-Term Supplementation of AZOMITE (Hydrated Sodium Calcium Aluminosilicate) in Finishing Diets on Growth Performance, Dietary Energy, and Carcass Yield of Hairy Lambs.

The aim of this study was to evaluate growth performance, dietary energy utilization, and carcass characteristics (carcass weight, dressing percentage, and visceral organ mass) of feedlot lambs fed different levels of AZOMITE (AZO), a source of volcanic clay composed of hydrated sodium calcium aluminosilicate, the same as that included in a finishing diet. For this reason, 36 Pelibuey × Katahdin crossbred intact male lambs (18.81 ± 3.04 kg initial weight) were used in a feeding trial lasting 81 d. Lambs were grouped by initial weight and assigned within six weight groupings to 18 pens in a randomized complete block design. Diets, offered ad libitum, were corn-based finishing diets with an 88:12 concentrate-to-forage ratio supplemented as follows: 1) no AZO inclusion (CTRL), 2) AZO inclusion at a 0.75% level (0.75AZO) in diet dry matter, 3) AZO inclusion at a 1.50% level (1.5AZO) in diet dry matter. Cracked corn was replaced by AZO. After the feeding trial was finished, lambs were slaughtered and carcass weight was registered and dressing percentage was calculated. The data were analyzed as a randomized complete block design, with the pen as the experimental unit. Water consumption and dry matter intake were not affected (p ≥ 0.11) by supplemental AZO. The incorporation of AZO into the diet increased gain efficiency and observed dietary net energy (NE), being maximal with 0.75% AZO inclusion (quadratic effect, p = 0.02). The observed-to-expected dietary NE in the control group was as anticipated (1.00) according to the estimated energy based on the ingredient composition in diet, while in the 0.75AZO group, the observed dietary energy was 6% above expected, indicating a greater efficiency in energy utilization destined to growth (quadratic effect, p = 0.006). Lambs that were fed the AZO treatment showed an improvement (linear effect, p = 0.04) in hot carcass weight (HCW), and tended (linear effect, p = 0.06) to improve dressing percentage (DP) as AZO was increased in the diet. Visceral organ mass was not affected by the treatments. It is concluded that AZOMITE clay can be included up to 1.5% in finishing diets for lambs without negative effects on the intake of water and feed. Lambs that received diets supplemented with 0.75% AZO showed greater improvements in feed efficiency and dietary energy utilization, but an inclusion of 1.50% resulted in greater improvements to HCW and DP. This is the first report regarding the effects of AZO supplementation in the dietary energy utilization of fattening hairy lambs. Further research about the effects of AZO supplementation on ruminal and total tract digestion, carcass and meat quality, and the health of lambs is needed in order to more deeply understand the effects of AZO on its productivity performance.

Adding red propolis to the diet of Lacaune lambs: Effects on animal health, ruminal environment, performance, and meat quality

This study determined the influence of red propolis ethanolic extract in lambs' diets on the ruminal environment, animal health, and growth. Two experiments were carried out to achieve these objectives. Pilot study: Twenty-four female Lacaune lambs were divided into four groups, with three replicates and two animals per replicate (pen): T0 (Control), TP1.3, TP2.7, and TP5.3, representing 0, 1.3, 2.7, and 5.3 mL of propolis extract per animal/day, respectively. The highest daily weight gain was observed in lambs that consumed 2.7 mL of propolis extract per day, and they also had the lowest feed conversion rate compared to the control. Lower total leukocyte counts were observed in lambs that consumed propolis extract compared to control due to lower granulocyte and lymphocyte counts. Ceruloplasmin and C-reactive protein levels were lower in the serum of lambs that consumed propolis compared to the control. Lambs that consumed 1.3 and 2.7 mL of propolis extract had lower TBARS levels than the control. The effect of treatment was observed for ruminal pH, which was higher in lambs that consumed propolis extract than in control. A lower concentration of short-chain fatty acids was observed in lambs that consumed propolis than the control due to lower concentrations of acetic and butyric acid. In experiment II, 36 male Lacaune lambs were selected and divided into two groups: MONENSIN (23.45 ppm of monensin per kg/dry matter (DM)) and PROPOLIS (3.8 mL of propolis per animal/day). The animals that consumed propolis extract had greater body weight, weight gain, and average daily gain. These also had a shorter time to reduce methylene blue, thus demonstrating more significant bacterial activity in the rumen. Furthermore, they had lower counts of Escherichia coli, total coliforms, and Enterobacteria. The meat's fatty acid profile in animals fed the red propolis extract showed higher concentrations of monounsaturated fatty acids. In conclusion, adding red propolis extract to the concentrate increased weight gain, average daily gain, and oxidative balance with an antimicrobial and anti-inflammatory effect.

Effect of replacing Tifton 85 hay with Moringa hay (Moringa oleifera L.) on the nutrient metabolism, metabolic profile, and water balance of sheep.

This study aimed to evaluate the effect of replacing Tifton 85 hay (TH) with Moringa hay (MH) on the intake, apparent digestibility, ingestive behaviour, rumen parameters, serum attributes, nitrogen balance, water balance, and urinary attributes of sheep. Thus, 5 rams, ½ Dorper + ½ Santa Inês, that were 12 ± 4 months of age with an initial body weight of 32.8 ± 2.6kg were distributed in metabolic cages in a Latin square design. The experiment lasted 85 days and was divided into five 17-day periods. The animals received rations with increasing replacement (0, 100, 200, 300, or 400g/kg of dry matter in the total diet) of TH for MH. The forage: concentrate ratio of the diets was 40:60. Replacing TH with MH reduced (P < 0.05) the intake of organic matter, crude protein, neutral detergent fibre (NDFap), and total digestible nutrients by sheep. The apparent digestibility of NDFap and the feeding and rumination efficiencies of NDFap were reduced (P < 0.05) when MH replaced TH in the animals' diet. This replacement did not influence (P > 0.05) serum urea, total protein, creatinine, or aspartate aminotransferase in sheep. Replacing TH with MH decreased water intake and excretion (P < 0.05). In addition, nitrogen excretion via urine, urinary creatinine, and nitrogen absorption decreased (P < 0.05) when TH was replaced with MH. However, there was an increase in the sheep's nitrogen retention and urine pH. We recommend replacing 30% TH with MH in the diet of lambs because it does not compromise nutrient metabolism.

Dried distiller’s grains in the diets of feedlot lambs: implications for production, carcass characteristics and rumen morphometrics

Context The demand and production of renewable fuels are boosting the production of biofuels. Agricultural industries have been playing a role in the increase of ethanol production from corn and, consequently, their by-products. Dried distiller’s grain (DDG) is a by-product of corn ethanol and can be used as a source of protein and energy in the diet of feedlot lambs. Aims The objectives of this experiment were to evaluate the effects of including DDG in high-concentrate diets on performance, rumen morpho-histology, and carcass characteristics in feedlot lambs. Methods Forty-five Santa Inês × Dorper male lambs with an initial body weight of 21 ± 3.2 kg (mean ± s.d.) and 82 ± 12 days old (mean ± s.d.) were distributed in a randomised complete-block design (nine blocks and five treatments). The experimental diets contained 900 g/kg of concentrate and 100 g/kg of coastcross hay, and DDG was used in replacement of soybean meal and corn. Lambs were fed one of the following five diets for 112 days: control without DDG (0DDG), or diet with 150 (150DDG), 300 (300DDG), 450 (450DDG) and 600 (600DDG) g/kg DM of DDG. Key results The inclusion of DDG from 150 up to 600 g/kg DM in the diet of the lambs linearly decreased (P &lt; 0.01) dry-matter intake (DMI), net energy of maintenance intake, net energy of gain, average daily gain, final body weight and feed efficiency (P &lt; 0.01). The inclusion of DDG linearly decreased (P ≤ 0.04) hot carcass weight, cold carcass weight, hot carcass yield and cold carcass yield. For ruminal morpho-histology, there was a linear decrease in the area of papillae and absorptive surface area (P &lt; 0.01) Conclusions An increase in the DDG level from 150 to 600 g/kg DM in the diet of lambs negatively affected feedlot performance, with detrimental effects on carcass traits and the development of rumen papillae. The lambs showed low acceptance of DDG, even at the lowest level of dietary inclusion (150g/kg DM) as DMI was impaired. Implications DDG should be used with caution in diets for finishing lambs. Dietary inclusion of DDG up to 150 g/kg DM is recommended. Higher inclusions levels may significantly affect performance and carcass weight and yield.

Soybean oil, linoleic acid source, in lamb diets: carcass traits and meat quality.

We developed a study to determine the ideal level of inclusion of soybean oil (SBOil) in the diet without affecting the quantitative and qualitative parameters of the carcass and meat of lambs in a feedlot system; therefore, determining the ideal level of inclusion. Forty male lambs (Santa Inês breed) were used. The initial body weight and age averaged 34.88 ± 3.19kg and 5months, respectively. Experimental units (lambs) were randomly distributed in 5 different diets: inclusion levels of SBOil: 0, 30, 60, 90, and 120g/kg of dry matter (DM). The SOil inclusion reduced the DM intake (P < 0.001), Total digestible nutrients (P = 0.004), and crude protein (P < 0.001). Total weight gain (P < 0.001) decreased with the SBOil inclusion and subcutaneous fat thickness (P = 0.017) showed the same behaviour. The final body weight decreased by 42.9g/kgDM until the inclusion level of 30g/kgDM; from this level it was reduced by 145g/kgDM. The hot and cold carcass weights (P = 0.013) decreased by 36.6g/kgDM after including 30g/kgDM of SBOil. Meat physicochemical composition was not altered (P > 0.05). Lower meat tenderness values ​​were obtained at the levels of 60 and 90g/kgDM. The inclusion above 30g/kgDM decreased meat tenderness. It is concluded that soybean oil should be included up to 30g/kgDM in diets. It is important to note that with diets with 60% concentrate, SBOil levels greater than 30g/kgDM promote yield losses.

PSXIII-25 Exploring crude glycerin as an alternative to corn in high-concentrate diets: Effects on performance and ruminal health in feedlot lambs

Abstract The search for increasingly efficient ruminant production systems has led to the utilization of high-concentration diets, with corn frequently serving as the primary ingredient. However, excessive and inappropriate use of corn can predispose animals to rumen acidosis, resulting in nutritional and metabolic disorders. Given this scenario finding safe and effective alternatives to replace corn has become imperative. Glycerin emerges as a promising substitute. The aim of this study was to evaluate the inclusion of glycerin as a total replacement for corn in high-concentrate diets (80%) for feedlot lambs. Lambs (n = 40) were randomly assigned in a randomized complete block design into two treatments, with one group receiving 30% DM crude glycerin in the total mixed diet and the other serving as the control group. The animals remained confined until they reached 35 kg of body weight (BW), at which point they were slaughtered. Performance and papillae data were collected and analyzed. Principal Component Analysis (PCA) was conducted to assess the relationship between days in the feedlot, average daily gain (ADG), rumenitis score, liver abscess incidence, number of papillae, papillae area (cm2), absorptive surface area (cm2), and papillae area (%). The PCA was performed using R Statistical Software (FactoMiner and Factoextra package). The two principal components (Dim1 and Dim2) accounted for 49% of the data variability. The first component (Dim1 = 30.1%) was positively correlated with treatment, days in the feedlot, number of papillae, papillae area, absorptive surface area, and papillae area. However, it was inversely correlated with ADG, rumenitis score, and liver abscess incidence. Animals that did not receive glycerin had greater ADG during the period (0.316 vs 0.272 kg; P = 0.075), spending less time in the feedlot (56 vs 62 d; P = 0.067), but they exhibited greater ruminitis score and liver abscess incidence values (P &amp;lt; 0.05). On the other hand, animals that received glycerin, despite spending more time confined, showed better values (P &amp;lt; 0.05) for number of papillae (62 vs 59 n/cm2), papillae area (0.07 vs 0.06 cm2), absorptive surface area (4.4 vs 3.91 cm2), and papillae area (90.41 vs 88.60%). In conclusion, the findings of this study highlight the potential of glycerin as a viable alternative to corn in high-concentrate diets for feedlot lambs. While animals receiving glycerin spent more time in feedlot, they exhibited improved ruminal health parameters, such as increased papillae development and surface area, suggesting enhanced nutrient absorption. These results underscore the importance of exploring alternative feed ingredients to mitigate the risk of ruminal acidosis and its associated economic and health implications in ruminant production systems. The inclusion of 30% DM crude glycerin in the total mixed diet is recommended for feedlot lambs, however, further studies must be conducted to confirm its effectiveness and safety of use.

Dietary Effects of Black-Oat-Rich Polyphenols on Production Traits, Metabolic Profile, Antioxidative Status, and Carcass Quality of Fattening Lambs

The study aimed to establish the dietary effects of black oat rich in polyphenols on the production traits, metabolic profile, antioxidant status, and carcass quality of fattening lambs, after weaning. In the BO group, in the feed mixture, common oats replaced the black oat compared to the CO group. The research comprehensively investigated production indicators, blood metabolic profile, antioxidant status, and lamb carcass quality. No significant differences were found in the fattening or slaughter characteristics of lamb carcasses, except for lower pH1 values in BO lamb carcasses. Significant increases in RBC, HCT, and MCV levels as well as TP, ALB, and GLOB concentrations and GPx and SOD activities in the blood of BO lambs were found. The glucose and EOS content as well as the activity of the enzymes ALT and ALP were significantly lower in the blood of the BO group than in the CO group. In the liver, the DPPH activity was significantly higher in the BO lambs compared to the CO lambs. The observed changes in glucose, protein metabolism, and antioxidant status in the blood and tissues of lambs indicate that the use of polyphenol-rich black oats in the diet of lambs under stress conditions is justified.

Effects of protein grass hay as alternative feed resource on lamb's fattening performance and meat quality

Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.

PSIX-29 Effects of including sprouted barley in the diets of feeder lambs

PSIX-29 Effects of including sprouted barley in the diets of feeder lambs

The assessment of zeolite addition to diets with or without urea on some productive and physiological indicators in Awassi lambs

BackgroundInterest is growing in the search for alternatives to traditional feed additives, so this study aimed to investigate the effect of adding zeolite to the concentrate diets of Awassi lambs with or without urea on growth performance, nutrient digestion, and health status. A total of 45 Awassi lambs similar in weight (24 ± 2 kg) and age (3 months ± 4 days) were divided into three groups: the first group (G1) fed on a concentrate diet supplemented with 1% urea; the second group (G2) fed on the concentrate diet supplemented with 1% urea and 3% zeolite, and the third group (G3) fed on a urea-free diet supplemented with 3% zeolite.ResultsThe results showed a significant increase (P ≤ 0.05) in final live weight, daily and total weight gain for group G2 compared to groups G1and G3, with a significant superiority (P ≤ 0.05) of group G3 over the control group G1. Significant improvement (P < 0.05) was also observed in feed consumption and feed conversion ratio in diets supplemented with zeolite for groups G2 and G3 compared to the control group G1. Additionally, there was a significant increase (P ≤ 0.05) in nutrient digestion and nutritional value in the diet of group G2 containing urea with added zeolite compared to groups G1 and G3. Zeolite did not affect the levels of glucose, triglycerides, cholesterol, and albumin in the blood, but a significant increase (P ≤ 0.05) in total blood protein level and a significant decrease (P ≤ 0.05) in blood urea level were noted for groups G2 and G3 compared to the control group G1.ConclusionsAdding zeolite to urea-containing concentrate diets improved growth rates and nutrient digestion, of Awassi lambs. In diets without urea, zeolite improved growth rates without affecting nutrient digestion coefficients, in both types of diets, zeolite increased total protein levels and decreased blood urea levels, with all physiological indicators in lambs blood remaining within normal limits.

Replacing alfalfa-based total mixed ration with Moringa leaves for improving carcass and meat quality characteristics in lambs

The expected increase in the population will put more pressure on resources, which means there will be a greater demand for food and the need for different ingredients to feed animals. This study aimed to explore the potential benefits of replacing alfalfa-based total mixed ration (TMR) with Moringa spp. On carcass characteristics and meat quality traits in lamb. The experiment involved 60 intact male lambs of the Harri breed, averaging 24 ± 1 kg in weight and approximately 5 months old. Lambs were randomly divided into five feeding groups: T1 (40 % alfalfa-based TMR), T2 (40 % M. oleifera), T3 (40 % M. peregrina), T4 (20 % alfalfa-based TMR + 20 % M. oleifera), and T5 (20 % alfalfa-based TMR + 20 % M. peregrina. The results confirmed that incorporating Moringa spp. Into lamb diets significantly reduced intramuscular fat content. Supplementation also improved tenderness, texture properties, and water-holding capacity. Additionally, the treatment groups exhibited a significant decrease in total non-carcass components compared to the control group. Overall, these findings suggest positive changes and enhancements in lamb carcass traits and meat quality attributes with Moringa spp. Supplementation, without observed adverse effects.

Copaiba oleoresin as a substitute for sodium lasalocid in finishing diets for lambs: carcass characteristics and meat quality

ABSTRACT The aim of this study was to evaluate the effects of copaiba oleoresin (CO) as a substitute for sodium lasalocid on the carcass characteristics and meat quality of feedlot lambs fed a high-concentrate diet. Twenty-four Pantaneiro lambs, aged 152 days and weighing an initial body weight of 21.2 ± 3.9 kg, were distributed in a randomised block design with three treatments and eight replications. The treatments correspond to the additive supplements: LAS (22.5 mg of sodium lasalocid/kg of diet); CO-0.5 (0.5 mL of CO/animal/day); CO-1.0 (1.0 mL of CO/animal/day). The doses of CO were administered to the animals orally with the aid of a graduated syringe. Lambs supplemented with LAS had higher hot carcass weight, cold carcass weight, cold carcass yield, and degree of fattening compared to CO-0.5, while CO-1.0 did not differ from LAS. It can be concluded that daily ingestion of CO up to 1.0 mL/lamb did not negatively affect carcass characteristics when compared to LAS supplementation. However, lower ingestion (0.5 mL/day) can reduce the carcass weight and carcass yield. Although CO supplementation minimally affected the meat quality and FA profiles, both doses reduced crude protein content in meat.

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

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

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

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

Effects of yeast and exogenous fibrolytic enzyme additives on lamb performance and feed efficiency.

Yeast and fibrolytic enzymes serve as additives incorporated into the nutrition of ruminants to regulate rumen fermentation and increase the digestibility of fiber, thereby enhancing the efficiency of rumen fermentation. Two experiments were conducted to assess the impact of five diets: a control diet without additives, diets with yeast (Saccharomyces cerevisiae) or exogenous fibrolytic enzymes (EFE), and diets with a blend of 0.7yeast + 0.3EFE or 0.7EFE + 0.3Yeast (based on recommended levels in g/kg of total DM). In the first experiment, 40 five-month-old Santa Ines lambs (mean weight 25.0 ± 1.3kg) were distributed in a completely randomized design (5 treatments and 8 lambs) for 81 days to evaluate performance, ingestive behaviour, and serum metabolites. In the second experiment, 25 Santa Ines male lambs weighing 25.7 ± 4.1kg were housed in metabolic cages, in a randomized design with 5 treatments and 5 lambs, evaluating digestibility, nitrogen balance, and rumen pH. EFE supplementation increased intakes of dry matter (DM), total digestible nutrients (TDN), and apNDF (mean of 38.1, 5.26, and 27%, respectively) compared to yeast or the 0.7yeast-0.3EFE blend. Feed conversion was most efficient (mean of 27.1%) in lambs fed Yeast, 0.7EFE + 0.3yeast, and the control diet. Lambs fed 0.7yeast + 0.3EFE spent less time eating (mean of 16.5%) and more time idling (mean of 10.75%), whereas EFE-fed lambs spent more time eating (mean of 19.73%), and 0.7EFE + 0.3yeast-fed lambs spent more time ruminating (mean of 20.14%). Control group lambs chewed and ruminated less (means of 24.64 and 17.21%, respectively) compared to other treatments. Lambs on the 0.7yeast + 0.3EFE blend had higher eating and rumination efficiency rates for DM and apNDF (mean of 19.11 and 17.95%, respectively) compared to other additive treatments or individual additives. They also exhibited lower (means 7.59g/d) urinary N excretion, with improved N retention (mean 3185g/d) compared to the control group. There were significant effects on serum albumin and cholesterol concentrations, with the 0.7yeast + 0.3EFE blend showing higher albumin (mean 4.08g/dL) levels, while diets without additives and yeast-EFE blends had higher cholesterol (mean of 62.51g/dL) concentrations. Including Saccharomyces cerevisiae yeast along with 0.7 yeast + 0.3 EFE blend is recommended when feeding similar lamb diets to those used herein because it improves the efficiency of intake, rumination of DM and NDF, and nitrogen utilization without affecting the lamb performance.

Inclusion of the Cistus ladanifer L. plant and its condensed tannin extract in lamb diets - Effects on animal antioxidant status and oxidative stability of meat

This study evaluated whether the incorporation of condensed tannin (CT) extract from Cistus ladanifer in lamb diets induces the same antioxidant protection as the C. ladanifer plant. How dietary CT can enhance the antioxidant status of animals and the oxidative stability of their products was also explored. Thirty-six lambs were used to evaluate the effect of three levels of C. ladanifer CT (without CT enrichment, medium, and high level of CT) and two ways of CT supply (C. ladanifer plant or C. ladanifer CT extract) on meat lipid and colour stability, and antioxidant status of muscle, rumen, abomasum, and faeces. The presence of CT monomers in muscle and CT content in digestive contents and faeces was evaluated. Cistus ladanifer plant and CT extract did not improve the lipid stability and antioxidant status of meat, but both CT sources enhanced the meat colour stability over storage time. Condensed tannin monomers were not identified in muscle. Intake of α-tocopherol decreased with inclusion of CT sources in diets. However, muscle α-tocopherol content was not affected by diets, suggesting that CT increase the α-tocopherol availability in muscle. Both CT sources increased antioxidant activity in the digestive contents, although, in the abomasum, C. ladanifer plant resulted in higher antioxidant activity than CT extract for the same CT level in the diet. No CT were detected in the faeces and both CT sources had a minor effect on the antioxidant activity, which could indicate the CT transformation in the gastrointestinal tract.