Modeling Gastrointestinal Tract Wet Pool Size in Small Ruminants.

The gastrointestinal tract (GIT) wet pool size (GITwps) refers to the total amount of wet contents in GIT, which in small ruminants can reach up to 19% of their body weight (BW). This study aimed to develop models to comprehensively predict GITwps in small ruminants using a meta-regression approach. A dataset was created based on 21 studies, comprising 750 individual records of sheep and goats. Various predictor variables, including BW, sex, breed, species, intake level, physiological states, stages and types of pregnancy, dry matter intake, and neutral detergent fiber intake (NDFI), were initially analyzed through simple linear regression. Subsequently, the variables were fitted using natural logarithm transformations, considering the random effect of the study and residual error, employing a supervised forward selection procedure. Overall, no significant relationship between GITwps and BW (p = 0.326) was observed for animals fed a milk-based diet. However, a strong negative linear relationship (p < 0.001) was found for animals on a solid diet, with the level of restriction influencing GITwps only at the intercept. Furthermore, the prediction of GITwps was independent of sex and influenced by species in cases where individuals were fed ad libitum. Pregnant females showed a noticeable reduction in GITwps, which was more pronounced in cases of multiple pregnancies, regardless of species (p < 0.01). The composition of the diet was found to be the primary factor affecting the modulation of GITwps, with NDFI able to override the species effect (p < 0.0001). Overall, this study sheds light on the factors influencing GITwps in small ruminants, providing valuable insights into their digestive processes and nutritional requirements.

Macromineral requirements for maintenance and growth in male and female hair sheep.

A better understanding of the nutritional requirements of sheep, especially in terms of minerals, is crucial for improving production. We estimated the net requirements for Ca, P, K, Mg, and Na for gain (NCag, NPg, NKg, NMgg, and NNag) and maintenance (NCam, NPm, NKm, NMgm, and NNam) in male and female hair sheep. Six datasets with 248 individual records of hair sheep (139 non-castrated males, 75 castrated males and 34 females) were used to estimate the net macromineral requirements for gain. To estimate the net macromineral requirements for maintenance, 52 observations (26 non-castrated and 26 castrated males) were used. A meta-analytical approach was applied, using non-linear mixed effects models and the study as a random effect. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe mineral requirements with a low level of model selection uncertainty. The adopted criteria allowed the choice of the best models to represent the macromineral requirements. The chosen models explained the observed variability in the sex, and the choices were based on a low level of uncertainty (w ≥ 0.90). Irrespective of sex, NCag and NPg decreased with increasing BW from 10 to 30 kg and average daily gain (ADG) of 150 g/day, ranging from 1.71-1.38; 1.83-1.57; 1.82-1.51 of Ca and 0.86-0.66; 0.92-0.78; 0.92-0.75 of P for non-castrated males, castrated males, and females, respectively. The NKg remained constant, with mean values of 0.26 g/day. The NNag range was 0.17 to 0.14 g/day for non-castrated males, 0.20 to 0.25 g/day for females, and constant (0.18 g/day) for castrated males with an increase in BW from 10 to 30 kg and an ADG of 150 g/day. Macromineral requirements for maintenance (mg/kg BW) and retention (%) were 23.70 and 54.30 for Ca, 25.33 and 79.80 for P, 11.74 and 5.00 for K, 2.63 and 8.50 for Mg, and 7.01 and 8.10 for Na for males. The International Committees did not provide inferences about the sex influence on mineral requirements. Our study indicates that sex is one factor that influences the macromineral requirements for gain. The information generated in this study can be used to optimize the mineral management of hair sheep in the growing phase in tropical regions.

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.

Sunflower Cake from the Biodiesel Industry in the Diet Improves the Performance and Carcass Traits of Nellore Young Bulls.

We aimed to determine the optimal inclusion level of sunflower cake (0, 90, 180, and 270 g/kg total DM) as a partial replacement of soybean meal and corn ground in young bulls' diets by examining nutrient intake and digestibility, ingestive behavior, nitrogen balance, metabolic serum profile, growth performance, and carcass traits. Thirty-two intact Nellore bulls (BW 374 ± 42.5) were distributed in a completely randomized design. The experiment lasted 90 days. The final BW of the animals was 515.25 ± 24.7. There was a linear decrease effect in the intake of DM, crude protein and nonfibrous carbohydrates, eating and rumination efficiency, N-urinary, N-total excretion, and blood urea nitrogen. Sunflower cake did not affect the NDF digestibility, nitrogen (N)-fecal excretion, blood metabolites, Longissimus lumborum muscle area, or subcutaneous fat deposition. There were linear and quadratic effects on the eating and rumination time, microbial protein production and efficiency, gamma-glutamyl transferase and cholesterol serum concentrations, and muscle carcass tissue. There was a quadratic effect on ether extract intake, final BW, and total gain with the inclusion of sunflower cake in the young bull's diet. The replacement of soybean meal and corn ground with sunflower cake at the level of 90 g/kg of DM in the diet of young bulls is recommended because it reduces the DM intake and digestibility, increases microbial protein synthesis and muscle tissue deposition, and consequently improves the performance, feed efficiency, and carcass traits.

Performance, Digestibility, Nitrogen Balance and Ingestive Behavior of Young Feedlot Bulls Supplemented with Palm Kernel Oil.

Vegetable oils can be used to increase energy density in diets; manipulate rumen fermentation; and alter the capacity for degradation, digestion and absorption of nutrients. Two experiments were conducted to evaluate palm kernel oil (PKO) in the diet of confined bulls with the inclusion of 0.0, 11.5, 23.0 and 34.6 g PKO/kg dry matter (DM). The first experiment evaluated nutrient intake, performance, ingestive behavior and carcass characteristics. In the second experiment, steers crossbred with a ruminal cannula were used to evaluate digestibility, nitrogen balance, microbial protein synthesis, short-chain fatty acid levels and protozoal counts. The results showed that the inclusion of PKO linearly reduced intake in kg/day (DM, crude protein-CP, neutral detergent fiber-NDFap, nonfibrous carbohydrates-NFC and total digestible nutrient-TDN) and digestibility (DM, NDFap and TDN). Ether extract intake increased quadratically with the predicted maximum intake of 15.4 g/kg DM. Regarding ingestive behavior, there was a quadratic increase in rumination time and a quadratic reduction in idle time. Nitrogen balance, nitrogen intake, nitrogen retention, microbial protein production, acetate, butyrate, acetate/propionate ratio and protozoa count showed linear decreases due to dietary PKO inclusion. Regarding the carcass characteristics, linear decreases were observed for the final weight, average daily gain, hot carcass weight, cold carcass weight, hot carcass yield, cold carcass yield, loin eye area and subcutaneous fat thickness. The inclusion of PKO at up to 34.6 g/kg DM in diets for confined bulls reduces intake, negatively affecting digestibility, performance and carcass characteristics.

Effect of Dietary Palm Kernel Oil on the Quality, Fatty Acid Profile, and Sensorial Attributes of Young Bull Meat.

Lipid supplementation through vegetable oils in diets for ruminants can be a nutritional strategy to increase energy density, manipulate ruminal fermentation and change the physicochemical composition and sensorial properties of meat. This study evaluated the optimal dietary inclusion of palm kernel oil (PKO) for Nellore bulls on meat quality. The diets consisted of 0.0, 11.5, 23.0, and 34.6 g/kg dry matter (DM) PKO levels. PKO inclusion did not influence the centesimal composition, pH, color indices, water holding capacity, cooking loss, or shear force of the beef. There were linear increases in the concentrations of lauric acid (C12:0) and myristic acid (C14:0) in the bull's meat. However, palmitic acid (C16:0), oleic acid (C18:0), vaccenic acid (t-11-C18:1) and conjugated linoleic acid (CLA), ∑n - 6, ∑n - 3, ∑n - 6/∑n 3, the hypocholesterolemic: hypercholesterolemic ratio of the fatty acid content, and the thrombogenicity index were not affected. There were linear reductions in the oleic acid meat concentration (c-9-C18:1) and elongated enzymatic activity when PKO was added to the bull diet. The atherogenicity index increased linearly due to PKO inclusion in the bull diet. No effect of the inclusion of PKO on meat flavor, perception of tenderness, juiciness, or global acceptance from the sensorial evaluation was recorded. The inclusion of PKO up to 34.6 g/kg DM can be recommended to supplement young bulls with no effects on meat composition and quality characteristics.

Physicochemical Composition and Fatty Acid Profile of Goat Kids' Meat Fed Ground-Corn-Grain Silage Rehydrated with Different Additives.

The effects of the replacement of dry ground corn (GC) with corn-grain silage rehydrated with water (RCSwater), cactus pear mucilage (RCSmucilage), and whey (RCSwhey) on the growth, physicochemical composition, and fatty acid profile of goat kids' meat were investigated. Thirty-two crossbred goat kids (16.4 ± 2.50 kg initial weight) were assigned in a randomized block design with four treatments and eight repetitions. The NDF intake of goat kids fed with RCSmucilage was higher in comparison to RCSwater and RCSwhey (p = 0.0009). The dietary replacement of GC by RCSmucilage increased the final weight (p = 0.033) and meat-cooking losses (p = 0.0001) of kids. The concentrations of oleic (p = 0.046), 11,14-eicosadienoic (p = 0.033), and EPA (p = 0.010) were higher in the meat of kids fed with RCSmucilage and RCSwhey, and the α-linolenic concentration was higher (p = 0.019) for animals feeding with RCSmucilage. Meat from kids fed with RCSwhey presented the lowest ∑SFA and the highest ∑MUFA. In contrast, the ∑PUFA (p < 0.012) was higher for goats fed with RCSwater. The ∑ω3 (p < 0.0001) was higher in animals fed with RCSmucilage and RCSwhey. Desirable fatty acids were higher (p = 0.044) in animals fed with RCSmucilage and RCSwhey, and the atherogenicity (p = 0.044) and thrombogenicity (p < 0.0001) indexes were lower for goats fed the RCSwhey diet. The enzymatic activities of Δ9desaturase (C16) were higher (p = 0.027) in goat kids fed with GC and RCSmucilage, and Δ9desaturase (C18) was higher (p = 0.0497) when goats were fed with RCSmucilage and RCSwhey. Elongase activities were higher (p = 0.045) in goat kids fed with GC and RCSwater. The total replacement of GC by RCSmucilage is recommended in the diet of goat kids due to improvements in the weight gain and proportion of desirable fatty acids in the meat. In addition, RCSmucilage promoted better conservation of the silage at a lower cost when compared to commercial additives.

Maintenance and Growth Requirements in Male Dorper × Santa Ines Lambs.

The aim of this study was to estimate the energy and protein requirements for maintenance and growth of lambs. A total of 35 crossbreed Dorper × Santa Ines lambs [31 ± 1.28 kg of initial body weight (BW) and 4 months old] were distributed in a completely randomized design with three treatments groups (ad libitum, 30 and 60% of feed restriction). Five lambs were slaughtered at the beginning of the experimental trial as a reference group to estimate the initial empty BW (EBW) and body composition. When the animals of the ad libitum treatment reached a BW average of 47.2 kg, at day 84 of trial, all lambs were slaughtered. The feed restriction promoted reduction in body fat (P < 0.001) and energy concentration (P < 0.001), while protein showed a quadratic response (P = 0.05). The equations obtained for NEg and NPg requirements were 0.2984 × EBW0.75 × EBWG0.8069 and 248.617 × EBW-0.15546, respectively. The net energy (NEm) and protein (NPm) for maintenance were 71.00 kcal/kg EBW0.75/day and 1.76 g/kg EBW0.75/day, respectively. In conclusion, the NEg and NPg requirement for lambs with 30 kg of BW and 200 g of average daily gain (ADG) were 0.736 Mcal/day and 24.38 g/day, respectively. Our findings indicate that the NEm for crossbreed Dorper × Santa Ines lambs is similar to those recommended by the international committees; however, we support the hypothesis that the requirements for gain are lower.

Physicochemical Quality, Fatty Acid Composition, and Sensory Analysis of Nellore Steers Meat Fed with Inclusion of Condensed Tannin in the Diet.

This study was conducted to test the effect of dietary tannin on the fatty acid profile and sensory attributes of meat from Nellore steers. Thirty-two Nellore bull male were distributed in a completely randomized design and fed diets with condensed tannin extract as follows: 0, 10, 30, and 50 g/kg total DM basis. The physicochemical composition of the meat, lipid oxidation, fatty acid profile, flavor, tenderness, and overall acceptance were evaluated. There was a linear decrease (P ≤ 0.05) on lipid content, tenderness, cooking weight loss, myristic, palmitic, and oleic acids in meat as tannin increased in the diets. The total saturated and monounsaturated fatty acids, the atherogenicity index decreased. However, a linear increase (P ≤ 0.05) was observed for linoleic, linolenic, arachidonic, eicosapentaenoic, and docosapentaenoic acids. The physicochemical characteristic of the meat, such as moisture, ash, and protein contents, water retention capacity, final pH, Warner-Bratzler shear force, collagen, and color indexes (lightness, redness, yellowness, and chrome) did not change with dietary tannin. Also, CLA, n-6:n-3 ratio, Δ9 -desaturase, and elongase activity were not different among diets. In conclusion, condensed tannin linearly increases unsaturated fatty acids and decreases the atherogenicity index of meat; thus, it can be recommended at the highest level (50 g/kg DM) in the diet of Nellore steers. PRACTICAL APPLICATION: Agriculture byproducts plays an important part in the diet of ruminant animals and consequently on food chain and has implications for the composition and quality of the livestock products (milk, meat, and eggs) that people consume. Feeding tannin to steers increases the amount of unsaturated fatty acids and meat tenderness, with a concomitant reduction on saturated fatty acids and the atherogenicity index in meat. Thus, we recommend adding tannin to steer diets to reduce the risk factors for cardiovascular diseases in red meat for human consumption.

Effects of quantitative feed restriction and sex on carcass traits, meat quality and meat lipid profile of Morada Nova lambs.

BACKGROUND: An experiment was conducted to evaluate the effects of feed restriction (FR) and sex on the quantitative and qualitative carcass traits of Morada Nova lambs. Thirty-five animals with an initial body weight of 14.5 ± 0.89 kg and age of 120 d were used in a completely randomized study with a 3 × 3 factorial scheme consisting of three sexes (11 entire males, 12 castrated males and 12 females) and three levels of feeding (ad libitum - AL and 30% and 60% FR). RESULTS: Entire males presented greater hot and cold carcass weights (P < 0.05), followed by castrated males and females. However, the hot carcass yield was higher for females and castrated males than for entire males. Luminosity values were influenced (P < 0.05) by sex, with entire males presenting higher values than castrated males and females. Females showed higher (P < 0.05) concentrations of linoleic acid and arachidonic acid in the meat of the longissimus thoracis muscle. The meat of animals submitted to AL intake and 30% FR showed similar (P > 0.05) concentrations, and the concentrations of palmitic acid, palmitoleic acid, stearic acid, oleic acid and conjugated linoleic acid were higher (P < 0.05) than those of animals with 60% FR. The meat of females had a higher ω6/ω3 ratio and lower h/H ratio, and females had greater levels of feeding. The meat of animals on the 60% FR diet had a greater ω6/ω3 ratio, lower h/H ratio and lower concentration of desirable fatty acids in addition to a greater atherogenicity index (AI) and thrombogenicity index (TI). CONCLUSION: Lambs of different sexes had carcasses with different quantitative traits without total influence on the chemical and physical meat characteristics. The lipid profile of the meat was less favorable to consumer health when the animals were female or submitted to 60% feed restriction.

Supplementation with Cashew Nut and Cottonseed Meal to Modify Fatty Acid Content in Lamb Meat.

This study evaluates the effect of cashew nut meal (CNM), whole cottonseed (WCS), and calcium salts of long-chain fatty acids (Ca-LCFA) on the fatty acid profiles of meat from hair lambs. Thirty-five 60-d-old, male, noncastrated Santa Ines lambs with an initial average body weight of 13.00 ± 1.80 kg were used in a randomized complete-block design with 7 blocks and 5 treatments. The experimental treatments consisted of a control diet (CON) without supplemental lipids and 4 test diets with different lipid supplements that were selected according to the degree of protection from ruminal hydrogenation and their polyunsaturated fatty acid richness. The tests diets included the following modifications: supplementation with WCS, supplementation with CNM, supplementation with both cottonseed and CNM (CSCNM), and supplementation with Ca-LCFA. The C18:1n9c content was highest in the meat of the animals fed the CNM diet (42.00%). The meat from lambs fed the WCS and Ca-LCFA diets had higher C18:0 contents (25.23 and 22.80%, respectively). The C16:1 content was higher in the meat from the animals fed the CNM and CON diets (1.54 and 1.49%, respectively). C18:2c9t11 concentration was higher in the meat from the animals fed the Ca-LCFA and CNM diets. The estimated enzyme activity of Δ9-desaturase C18 was highest in the muscles of the lambs fed the CON, CNM, and CSCNM diets. The use of cashew nuts in the diet resulted in an increase in the C18:2c9t11 content of the lamb meat, which improved the nutritional characteristics of the fat.

Color, sensory and physicochemical attributes of beef burger made using meat from young bulls fed levels of licuri cake.

BACKGROUND: Licuri cake is a biodiesel byproduct and has been tested as an alternative feed additive for use in cattle production. This study analyzed the color, sensory and chemical attributes of burger meat from bovines. Thirty-two young Nellore bulls were used, housed in individual pens and distributed in a randomized experimental design with four treatments: no addition or the addition of 7, 14 or 21% (w/w) licuri cake in the dry matter of the diet. RESULTS: Interactions between the licuri cake level and the physicochemical variables (P > 0.05) were observed. Additionally, an interaction was observed between the licuri cake level and the burger beef color parameter lightness index (L*) (P = 0.0305). The L* value was positively and linearly correlated with the proportion of licuri cake in the diet of young bulls. The level of inclusion of licuri cake did not affect (P > 0.05) the sensory characteristics; the variables were graded between 6 and 7, indicating good overall acceptance. CONCLUSION: Up to 21% (w/w) licuri cake can be included in the diet of young bulls without negatively impacting on beef burger quality. © 2015 Society of Chemical Industry.