Lambs supplemented with Amazonian oilseed co-products: Meat quality and fatty acid profile.

The Amazon has a wide variety of oilseeds that generate a huge amount of co-products with potential for use in animal nutrition. The objective was to use alternative resources (oilseed cakes) in the feeding of lambs to assign a sustainable destination to this biomass, and evaluate its influence on the quality and fatty acid (FA) profile of the meat. Twenty-four lambs, male, castrated, crossbred Dorper × Santa Inês, weighing 30 ± 1.3 kg of initial body weight, were distributed in a completely randomized design in 4 treatments (diets) with six replications (animals). The control diet (Control) contained corn and soybean meal as main ingredients, which were partially replaced in the other diets by cupuassu cake diet (Cup), palm kernel cake diet (Palm) and tucuma cake diet (Tuc). The inclusion of Amazon cakes influences the lipid (P = 0.02) and protein (P < 0.01) composition of meat (longissimus lumborum); reduces cooking losses (P < 0.01); influences the colors (L, a, b), chroma, and Hue Angle (P < 0.01); promotes changes in total FA composition and FA profile (P < 0.05); reduces hypocholesterolemic FA (h) (P = 0.01), but does not influence hypercholesterolemic (H) and indices h:H, AI and TI (P > 0.05). The inclusion of oilseed cakes influences the chemical composition, physical parameters, composition and fatty acid profile of the meat, but does not influence the indicators of atherogenicity, thrombogenicity and cholesterolemia.

Large-scale analysis of sheep rumen metagenome profiles captured by reduced representation sequencing reveals individual profiles are influenced by the environment and genetics of the host.

BACKGROUND: Producing animal protein while reducing the animal's impact on the environment, e.g., through improved feed efficiency and lowered methane emissions, has gained interest in recent years. Genetic selection is one possible path to reduce the environmental impact of livestock production, but these traits are difficult and expensive to measure on many animals. The rumen microbiome may serve as a proxy for these traits due to its role in feed digestion. Restriction enzyme-reduced representation sequencing (RE-RRS) is a high-throughput and cost-effective approach to rumen metagenome profiling, but the systematic (e.g., sequencing) and biological factors influencing the resulting reference based (RB) and reference free (RF) profiles need to be explored before widespread industry adoption is possible. RESULTS: Metagenome profiles were generated by RE-RRS of 4,479 rumen samples collected from 1,708 sheep, and assigned to eight groups based on diet, age, time off feed, and country (New Zealand or Australia) at the time of sample collection. Systematic effects were found to have minimal influence on metagenome profiles. Diet was a major driver of differences between samples, followed by time off feed, then age of the sheep. The RF approach resulted in more reads being assigned per sample and afforded greater resolution when distinguishing between groups than the RB approach. Normalizing relative abundances within the sampling Cohort abolished structures related to age, diet, and time off feed, allowing a clear signal based on methane emissions to be elucidated. Genus-level abundances of rumen microbes showed low-to-moderate heritability and repeatability and were consistent between diets. CONCLUSIONS: Variation in rumen metagenomic profiles was influenced by diet, age, time off feed and genetics. Not accounting for environmental factors may limit the ability to associate the profile with traits of interest. However, these differences can be accounted for by adjusting for Cohort effects, revealing robust biological signals. The abundances of some genera were consistently heritable and repeatable across different environments, suggesting that metagenomic profiles could be used to predict an individual's future performance, or performance of its offspring, in a range of environments. These results highlight the potential of using rumen metagenomic profiles for selection purposes in a practical, agricultural setting.

Evaluation of the quality of meat and carcasses from sheep fed diets containing three types of oils.

The objective of this research was to evaluate the quantitative and qualitative characteristics of the carcass and meat of lambs fed with different types of oil. Thirty male, uncastrated, mixed breed (Santa Inês × Dorper) sheep were used in this experiment and were distributed in random blocks with three treatments and 10 replicates per treatment, where each animal represents a replicated experimental unit. The three treatments were the following experimental diets: soybean oil in natura; soybean oil after use in frying, and palm oil (Elaeis guineensis). The oils were incorporated into the sheep diets at a level of 4%. Carcasses were evaluated for hot and cold yield, loss due to cooling, finish, conformation, internal fat concentration, morphometric measurements, tissue composition, and commercial cuts. The addition of soybean oil in natura, residual soybean oil from frying, and palm oil to the sheep diets did not alter any of the evaluated characteristics, which therefore can be interpreted as favoring the use of any of these three oils as a supplement to their diet, and the three oils imparted good characteristics to the carcasses and the meat.

Combining host and rumen metagenome profiling for selection in sheep: prediction of methane, feed efficiency, production, and health traits.

BACKGROUND: Rumen microbes break down complex dietary carbohydrates into energy sources for the host and are increasingly shown to be a key aspect of animal performance. Host genotypes can be combined with microbial DNA sequencing to predict performance traits or traits related to environmental impact, such as enteric methane emissions. Metagenome profiles were generated from 3139 rumen samples, collected from 1200 dual purpose ewes, using restriction enzyme-reduced representation sequencing (RE-RRS). Phenotypes were available for methane (CH4) and carbon dioxide (CO2) emissions, the ratio of CH4 to CH4 plus CO2 (CH4Ratio), feed efficiency (residual feed intake: RFI), liveweight at the time of methane collection (LW), liveweight at 8 months (LW8), fleece weight at 12 months (FW12) and parasite resistance measured by faecal egg count (FEC1). We estimated the proportion of phenotypic variance explained by host genetics and the rumen microbiome, as well as prediction accuracies for each of these traits. RESULTS: Incorporating metagenome profiles increased the variance explained and prediction accuracy compared to fitting only genomics for all traits except for CO2 emissions when animals were on a grass diet. Combining the metagenome profile with host genotype from lambs explained more than 70% of the variation in methane emissions and residual feed intake. Predictions were generally more accurate when incorporating metagenome profiles compared to genetics alone, even when considering profiles collected at different ages (lamb vs adult), or on different feeds (grass vs lucerne pellet). A reference-free approach to metagenome profiling performed better than metagenome profiles that were restricted to capturing genera from a reference database. We hypothesise that our reference-free approach is likely to outperform other reference-based approaches such as 16S rRNA gene sequencing for use in prediction of individual animal performance. CONCLUSIONS: This paper shows the potential of using RE-RRS as a low-cost, high-throughput approach for generating metagenome profiles on thousands of animals for improved prediction of economically and environmentally important traits. A reference-free approach using a microbial relationship matrix from log10 proportions of each tag normalized within cohort (i.e., the group of animals sampled at the same time) is recommended for future predictions using RE-RRS metagenome profiles.

Nutrient intake, digestibility, performance, carcass traits and sensory analysis of meat from lambs fed with co-products of Amazon oilseeds.

Introduction: The increase in availability and nutritional composition of oilseed co-products has made it essential to study the use of this biomass. Methods: The objective of this work was to investigate the effects of including oilseed cakes on intake and digestibility, performance, carcass characteristics and meat sensory in feedlot lambs. Twenty-four crossbred Dorper × Santa Inês lambs, with initial body weight of 30 ± 1.3 kg, male, castrated, aged 4-5 months, were distributed in a completely randomized experimental design with four treatments (diets) and six replications (animals), confined in individual stalls for 70 days. Results: The inclusion of tucuma cake (Tuc) reduced dry matter intake (p < 0.01) and diets with cupuassu cake (Cup) and palm kernel cake (Palm) reduced dry matter digestibility (p < 0.05). The Tuc diet also provided the lowest final body weight (p = 0.02); lower average daily gain (p = 0.03); lower feed efficiency (p = 0.03) and lower carcass weight (p < 0.01). However, diets did not influence carcass yield (%), fat thickness (mm) and loin eye area (cm2; p > 0.05). Meat from lambs on the control diet was rated as less fibrous and more tender (p < 0.05). Conclusion: The inclusion of tucuma cake does not influence digestibility, but reduces intake, performance and influences carcass characteristics and meat texture. Diets with cupuassu cake or palmiste cake reduced digestibility, however, intake, performance and carcass characteristics were similar to the control diet.

Methane emission, intake, digestibility, performance and blood metabolites in sheep supplemented with cupuassu and tucuma cake in the eastern Amazon.

The use of co-products as a feed supplement for ruminants makes livestock sustainable and optimizes the use of available areas and animal performance. Furthermore, when cakes are used, the residual fat composition can influence ruminal metabolism and methane (CH4) production. This study aimed to assess the effects of a diet containing cupuassu (CUP; Theobroma grandiflorum) and tucuma (TUC; Astrocaryum vulgare Mart.) cakes on intake, digestibility, serum metabolites, performance, and CH4 emissions in confined sheep in the Amazon. Approximately 28 animals, Dorper-Santa Inês, castrated, with an average initial live weight (ILW) of 35 ± 2.3 kg, were distributed in metabolic cages, in a completely randomized design, with four treatments and seven replications: (1) Control (C40), without the addition of Amazonian cake and with 40 g of ether extract (EE)/kg of dietary dry matter (DM); (2) CUP, the inclusion of the CUP cake and 70 g of EE/kg; (3) TUC, the inclusion of the TUC cake and 70 g of EE/kg; and (4) Control (C80), without the addition of Amazonian cake and with 80 g of EE/kg of dietary DM, with roughage to concentrate ratio of 40:60. The use of the TUC cake as a feed supplement reduced the intake of DM, crude protein (CP), and EE compared to the inclusion of the CUP cake (p < 0.05); however, it increased the intake of neutral detergent fiber (NDF) by 32% (p < 0.01). The highest averages of DM (732 g/kg) and CP (743 g/kg) digestibility were presented in C40, while the highest digestibility of NDF was presented in TUC (590 g/kg). Albumin levels stayed above and protein levels were below the reference values, and the C40 diet also obtained below results for cholesterol, triglycerides and High Density Lipoprotein (HDL) (P < 0.05). Sheep fed CUP (91 g) and TUC (45 g) had lower daily weight gains (DWGs) than those fed with diets without the inclusion of cakes (C40 = 119 g; C80 = 148 g), and feed efficiency (FE) was also lower in CUP (84) and TUC (60) diets than in C40 (119) and C80 (137) diets. CH4 emissions were lower in animals fed TUC (26 L/day) and higher in C40 (35 L/day); however, TUC resulted in higher CH4 emissions in grams/body live weight (BW) gain/day (353 g/BW/day) vs. 183 g/BW/day (C40), 157 g/BW/day (C80), and 221 g/BW/day (CUP). The supplementation with cakes did not improve intake, digestibility and performance, did not compromise blood metabolites and did not reduce the enteric CH4 emission in confined sheep in the Amazon; however, the use of CUP cake showed similar results to the control treatments and did not increase CH4 emissions, as occurred with the inclusion of TUC cake.

Low-cost sample preservation methods for high-throughput processing of rumen microbiomes.

BACKGROUND: The use of rumen microbial community (RMC) profiles to predict methane emissions has driven interest in ruminal DNA preservation and extraction protocols that can be processed cheaply while also maintaining or improving DNA quality for RMC profiling. Our standard approach for preserving rumen samples, as defined in the Global Rumen Census (GRC), requires time-consuming pre-processing steps of freeze drying and grinding prior to international transportation and DNA extraction. This impedes researchers unable to access sufficient funding or infrastructure. To circumvent these pre-processing steps, we investigated three methods of preserving rumen samples for subsequent DNA extraction, based on existing lysis buffers Tris-NaCl-EDTA-SDS (TNx2) and guanidine hydrochloride (GHx2), or 100% ethanol. RESULTS: Rumen samples were collected via stomach intubation from 151 sheep at two time-points 2 weeks apart. Each sample was separated into four subsamples and preserved using the three preservation methods and the GRC method (n = 4 × 302). DNA was extracted and sequenced using Restriction Enzyme-Reduced Representation Sequencing to generate RMC profiles. Differences in DNA yield, quality and integrity, and sequencing metrics were observed across the methods (p < 0.0001). Ethanol exhibited poorer quality DNA (A260/A230 < 2) and more failed samples compared to the other methods. Samples preserved using the GRC method had smaller relative abundances in gram-negative genera Anaerovibrio, Bacteroides, Prevotella, Selenomonas, and Succiniclasticum, but larger relative abundances in the majority of 56 additional genera compared to TNx2 and GHx2. However, log10 relative abundances across all genera and time-points for TNx2 and GHx2 were on average consistent (R2 > 0.99) but slightly more variable compared to the GRC method. Relative abundances were moderately to highly correlated (0.68 ± 0.13) between methods for samples collected within a time-point, which was greater than the average correlation (0.17 ± 0.11) between time-points within a preservation method. CONCLUSIONS: The two modified lysis buffers solutions (TNx2 and GHx2) proposed in this study were shown to be viable alternatives to the GRC method for RMC profiling in sheep. Use of these preservative solutions reduces cost and improves throughput associated with processing and sequencing ruminal samples. This development could significantly advance implementation of RMC profiles as a tool for breeding ruminant livestock.

Meat quality of buffaloes finished in traditional or silvopastoral system in the Brazilian Eastern Amazon.

BACKGROUND: The present study aimed to assess the physical, chemical and sensory characteristics of meat from buffaloes finished in a Traditional System (TS) or Traditional + Silvopastoral System (TSPS) with dietary supplementation. Crossbred Murrah × Mediterranean buffaloes were raised from weaning to slaughter in the TS (n = 15) or were raised in the traditional system and finished in the TSPS (n = 15). After finishing, animals were slaughtered and their carcasses refrigerated for 24 h. The right side of each half-carcass was cut between the 12th and 13th ribs and the Longissimus thoracis muscle was removed. The cranial part underwent analyses of pH, color, weight loss as a result of cooking, water holding capacity, texture and sensory characteristics, whereas the rest of the muscle underwent microbiological analyses and determination of the chemical composition, fatty acid profile and mineral content. RESULTS: No major difference between finishing systems was found (P > 0.05) in the physical analyses and chemical composition of meat. The percentage of myristic acid (C14:0) and the sum of polyunsaturated fatty acids differed between treatments. The TS meat had the best 'characteristic meat aroma'. CONCLUSION: Considering the quality of meat produced in the TS or TSPS, it is concluded that finishing buffaloes in the pasture still represents the best alternative. © 2016 Society of Chemical Industry.