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.

Current Perspectives on Achieving Pronounced Enteric Methane Mitigation From Ruminant Production

Limiting global warming to 1.5°C above pre-industrial levels by 2050 requires achieving net zero emissions of greenhouse gases by 2050 and a strong decrease in methane (CH4) emissions. Our aim was to connect the global need for mitigation of the emissions of greenhouse gases and enteric CH4 from ruminant production to basic research on the biological consequences of inhibiting rumen methanogenesis in order to better design strategies for pronounced mitigation of enteric CH4 production without negative impacts on animal productivity or economic returns. Ruminant production worldwide has the challenge of decreasing its emissions of greenhouse gases while increasing the production of meat and milk to meet consumers demand. Production intensification decreases the emissions of greenhouse gases per unit of product, and in some instances has decreased total emissions, but in other instances has resulted in increased total emissions of greenhouse gases. We propose that decreasing total emission of greenhouse gases from ruminants in the next decades while simultaneously increasing meat and milk production will require strong inhibition of rumen methanogenesis. An aggressive approach to pronounced inhibition of enteric CH4 emissions is technically possible through the use of chemical compounds and/or bromoform-containing algae, but aspects such as safety, availability, government approval, consumer acceptance, and impacts on productivity and economic returns must be satisfactorily addressed. Feeding these additives will increase the cost of ruminant diets, which can discourage their adoption. On the other hand, inhibiting rumen methanogenesis potentially saves energy for the host animal and causes profound changes in rumen fermentation and post-absorptive metabolism. Understanding the biological consequences of methanogenesis inhibition could allow designing strategies to optimize the intervention. We conducted meta-regressions using published studies with at least one treatment with >50% inhibition of CH4 production to elucidate the responses of key rumen metabolites and animal variables to methanogenesis inhibition, and understand possible consequences on post-absorptive metabolism. We propose possible avenues, attainable through the understanding of biological consequences of the methanogenesis inhibition intervention, to increase animal productivity or decrease feed costs when inhibiting methanogenesis.

Sustainable feed resources for optimizing broiler performance in tropical countries

Soybean meal and grain corn are feedstuffs that normally used as the main ingredients in poultry feeds as a source of protein and energy in tropical countries. The availability of these feedstuffs for broiler nutrition nowadays is becoming more competitive. Thus, food security, especially in the developing countries, would be susceptible. Currently, efforts are being made to use alternative feedstuffs as a sustainable feed resources to substitute portion of soybean meal and grain corn in poultry diets due to their high price since both of the raw material were imported. In Malaysia, usage of PKC is common in ruminant diets, but limited in the non-ruminant diets especially in poultry diets due to the high fiber content of PKC. Several works have been conducted to increase the nutritional contents of PKC as one of the measures to reduce and/or eliminate the constraints of utilizing PKC in poultry diets. The method used to achieve this target is either through physical, chemical, biological or combination of these treatments. This paper discusses the use of PKC as the sustainable feed resources that can be incorporated in the poultry feeds. Hence, emphasis should be given to improve nutritional values of PKC in order to reduce feeding cost of poultry.

Measurements of Chemical Compositions in Corn Stover and Wheat Straw by Near-Infrared Reflectance Spectroscopy

Rapid, non-destructive methods for determining the biochemical composition of straw are crucial in ruminant diets. In this work, ground samples of corn stover (n = 156) and wheat straw (n = 135) were scanned using near-infrared spectroscopy (instrument NIRS DS2500). Samples were divided into two sets, with one set used for calibration (corn stover, n = 126; wheat straw, n = 108) and the remaining set used for validation (corn stover, n = 30; wheat straw, n = 27). Calibration models were developed utilizing modified partial least squares (MPLS) regression with internal cross validation. Concentrations of moisture, crude protein (CP), and neutral detergent fiber (NDF) were successfully predicted in corn stover, and CP and moisture were in wheat straw, but other nutritional components were not predicted accurately when using single-crop samples. All samples were then combined to form new calibration (n = 233) and validation (n = 58) sets comprised of both corn stover and wheat straw. For these combined samples, the CP, NDF, and ADF were predicted successfully; the coefficients of determination for calibration (RSQC) were 0.9625, 0.8349, and 0.8745, with ratios of prediction to deviation (RPD) of 6.872, 2.210, and 2.751, respectively. The acid detergent lignin (ADL) and moisture were classified as moderately useful, with RSQC values of 0.7939 (RPD = 2.259) and 0.8342 (RPD = 1.868), respectively. Although the prediction of hemicellulose was only useful for screening purposes (RSQC = 0.4388, RPD = 1.085), it was concluded that NIRS is a suitable technique to rapidly evaluate the nutritional value of forage crops.

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.

Effect of addition cattle feed supplement on in vitro fermentation, synthesis of microbial biomass, and methane production of rice straw fermentation basal diets

The objective of this study was to evaluate the influence of supplementation of cattle feed supplement (CFS) and concentrate in ruminant diets based on rice straw fermented (R) on in vitro rumen fermentation, microbial biomass synthesis, and enteric methane production. Five experimental diets were evaluated, consist of R = rice straw fermented 100%, RS = R + CFS 10%, RSC1, 2 and 3 = RS + Concentrate levels 10, 20 and 30 (%DM). Supplementation of CFS increased the gas production (P < 0.05) and highest in treatments RSC1 and 2 (44.09 and 44.87 ml/g substrate, respectively) and was decreased proportions of methane by inhibition rate until 49.80%. Ruminal protozoa population increased by CFS dan concentrate supplementation (P<0,05) and was dominated (>80%) of Entodinium genus. The treatments RS dan RSC1 promoted greater (P < 0.01) microbial biomass synthesis (386.32 and 312.39 mg/g substrate, respectively). In conclusion, the supplementation of CFS and concentrate in ruminant diets based on rice straw fermented can promote a greater synthesis of microbial biomass and mitigation of methane production.

330 3-nitrooxypropanol Supplementation of a Forage Diet Decreased Enteric Methane Emissions from Beef Cattle Without Affecting Apparent Total-tract Digestibility

Supplementation of ruminant diets with the investigational methane (CH4) inhibitor 3-nitrooxypropanol (3-NOP; DSM Nutritional Products, Switzerland) is as a promising mitigation strategy. However, most studies have examined high grain or mixed forage-concentrate diets. The objective of this study was to evaluate the effects of supplementing a forage diet with 3-NOP on rumen fermentation, CH4 emissions and apparent total-tract nutrient digestibility. Eight ruminally cannulated beef heifers (BW = 514 kg) were randomly allocated to two treatments in a crossover design with 49-d periods. Dietary treatments were: control, high-forage diet (90% forage DM basis) without 3-NOP; and NOP, control diet supplemented with 150 mg 3-NOP/kg DM. After a 14-d diet adaption, dry matter (DM) intake (DMI) was recorded daily. Rumen contents were collected on days 17 and 28 for volatile fatty acid (VFA) analysis, whereas ruminal pH was continuously monitored from day 20 to 27. Diet digestibility was measured on day 38 to 41 by total collection of feces. Enteric CH4 emissions were measured on days 46 to 49 in chambers. Dry matter intake was lower (P = 0.001) for NOP (10.0 kg/d) as compared with control (10.2 kg/d). However, DM, neutral and acid detergent fiber, and crude protein digestibilities were similar between treatments (P ≥ 0.29). Although total VFA concentration was not affected by treatment (P = 0.19), the reduction in acetate and increase in propionate proportion for NOP lowered (P &lt; 0.001) the acetate to propionate ratio by 18% as compared with control. Mean pH was lower (P = 0.03) for control (6.46) than NOP (6.57). Furthermore, CH4 yield (g/kg DMI) was 21.6% less (P &lt; 0.001) for NOP relative to control (25.5 g/kg DMI). Overall, the results indicate that enteric CH4 emissions were effectively decreased with 3-NOP supplementation of a forage diet without affecting apparent total-tract digestibility of nutrients.

PSXV-6 The effect of ultrafine iron particles on the adaptation of the digestive system of cattle to fat diets

The aim of our study was to determine the possibility of using ultrafine Fe particles (2.2 mg/head/day) as modulators of metabolic activity when using vegetable soybean and sunflower oils in ruminant diets. The studies carried out on calves with external duodenal anastomosis (diet – grassland hay (2 kg), a mixture of concentrates (1.5 kg), corn silage (5 kg), wheat straw (1 kg), oil-3% of the dry matter of the diet). The digestibility of the nutritional components of the diet analyzed daily throughout the study period. The collection of pancreatic juice was carried out for 8 hours with an interval of 60 minutes on the 7th day, the determination of the amount and enzymatic activity of the juice carried out “incito.” Introduction of ultrafine Fe particles significantly increased the digestibility of organic matter by 38% (P ≤ 0.05) with the introduction of vegetable soybean oil, crude fat by 28.4% (P ≤ 0.05) with the introduction of sunflower oil. Additional introduction of ultrafine Fe particles significantly increased the level of pancreatic secretion when sunflower oil was introduced by 59.8%, soybean oil by 56% (P ≤ 0.05). Additional inclusion of ultrafine iron particles contributed to the decrease of lipase, protease and amylase activity by 86,8%, 37,4% and 33% (P ≤ 0,05) in the sunflower oil group, by 68,2% of lipase, by 24,6% of amylase in the soybean oil group (P ≤ 0,05). A significant increase in the level of NO-metabolites was recorded in the group receiving soybean oil by 37.5 % (P &lt; 0.05). This study shows the potential use of ultrafine Fe particles as a mineral supplement to regulate the functional activity of digestive and metabolic processes in ruminants, which may play a positive role in increasing the bioavailability of nutritional components of diets. This research performed with financial support from the project 0761-2019-0005.

316 Determination of the Chemical and Phytochemical Composition of the Methanolic Extract of Urochloa Humidicola for Use as a Phytogenic Additive in Ruminant Diets

Plant extract is an excellent alternative to reduce methane emissions and ameliorate ruminal fermentation due the presence of the secondary metabolites, however, there are many studies with plants used on human’s diet that shows a good result but may occur competition and elevate the costs for the system. Plants consumed by animal have secondary metabolites in quantity and diversity, it can be a good strategy. This work aimed to determine the bromatological composition and characterize the Urochloa humidicola methanol extract such as the presence of secondary metabolites. The samples of the leaves of U. humidicola were collected, dried in the shade with temperature below 40°C, ground in a willey mill in 2 mm particles and subjected to cold maceration with methanol. The solution obtained was filtered by filter paper and concentrated in a rotary evaporator and put to finish the process, drying under airflow. The results of bromatological analyses were subjected to ANOVA by comparing averages by Fisher’s test using the 9.1 Saeg software and phytochemical prospecting testes were characterized as the intensity of the presence of each class of metabolites and represented via the cross-system where:(+++) implies a large presence, (++) implies a considerable presence, (+) implies a small presence and (0) implies a no presence. The dry crude methanolic extract was subjected to analysis of chemical composition and phytochemical prospecting. The extract showed 10.20% crude protein and 35% ether extract and traces of fibrous constituents, because the methanol extraction extracted only soluble constituents. A phytochemical prospecting was positive for the presence of saponin. tannin, alkaloids, catechins, non-protein amino acids and saccharides and was negative for the presence of flavonoids and purines. The U. humidicola methanol extract can be used as a phytogenic additive in the feeding of ruminants.

333 Assessment of Spent Hemp Biomass as a Potential Feedstuff in Ruminant Diets

The 2018 Farm Bill removed hemp (Cannabis sativa) from the Controlled Substances Act, classifying it as an agricultural product. The process of cannabidiol extraction from hemp yields large quantities of spent hemp biomass (SHB) that may potentially be included in animal diets. However, the use of SHB in animal diets has not been approved by FDA yet since its effect on animal health, production and product quality is still unknown. Thus, a feeding study was carried out to investigate the effects of varying levels of SHB and a four-week withdrawal period on feed intake and liveweight gains of weaned lambs. A total of 35 weaned, male Polypay lambs kept in single pens were randomly assigned to five feeding treatments (n=7) and fed diets containing either no SHB (CON) or SHB at 10% (LH1) or 20% (HH1) for 4 weeks with 4 weeks withdrawal from SHB, or SHB at 10 (LH2) or 20% (HH2) for 8 weeks. The nutritive analysis of the SHB indicated a high-quality feed, with 20% (DM) crude protein and 27% NDF. Dry matter (DM) intake of lambs was negatively affected by 20% SHB during the first period. In the second period, DM intake was larger in lambs fed 10% SHB vs. CON, with the largest feed intake observed in HH1 lambs. In contrast, none of the performance data, including liveweight gains, were different across the groups and periods. Feeding 20% SHB decreased plasma cholesterol, NEFA, BHBA, Ca, and Cl and increased urea and Mg, while 10% SHB increased glucose, cholesterol, and NEFA. Our findings indicated that 10% SHB can be included in ruminant diets without causing any detrimental effect on performance with a possible positive effect on feed intake. The long-term feeding of 20% SHB strongly affects the metabolism.