Effects of tea saponins on in vitro ruminal fermentation and growth performance in growing Boer goat

Effects of allicin on growth performance, antioxidant profile, and microbiota compared to monensin of growing goats

Allicin is a sulfur-containing compound extracted from raw garlic (Allium sativum L.). We compared the effect of allicin addition on growth performance, serum biochemical parameters, and rumen microbiota of goats compared to monensin. Twenty-four Anhui white goats were assigned randomly to one of three dietary treatments: 1) a basal diet (CON); 2) the basal diet with allicin addition at 750 mg per head per day (AC); 3) the basal diet with monensin addition at 30 mg per kg of diet (MS). Animals were fed for 8 weeks. Results showed the average daily gain, and feed efficiency was increased with allicin and monensin addition. Serum levels of IgG, total superoxide dismutase, and glutathione peroxidase were higher in the AC group than those in the CON and MS groups. The microbiota analysis revealed that monensin addition mainly affected genera related to carbohydrate and protein metabolism, and allicin mainly affected genera related to energy metabolism and intestinal health. In conclusion, allicin could improve growth performance and have advantages over monensin in improving the antioxidant capacity and immune function of goats. Allicin may be a potential alternative to monensin.

Dung treated by high-temperature composting is an optimal bedding material for suckling calves according to analyses of microbial composition, growth performance, health status, and behavior

Bedding materials are important for suckling buffalo calves. Treated dung has been used as a bedding material for dairy cows but the lack of an appropriate safety assessment limits its application. In this study, we evaluated the feasibility of treated dung (TD) as a bedding material for suckling calves by comparing TD with rice husk (RH) and rice straw (RS) bedding materials. The TD was prepared through high-temperature composting by Bacillus subtilis. Thirty-three newborn suckling buffalo calves (Bubalus bubalis, 40.06 ± 5.79 kg) were randomly divided into 3 bedding material groups (TD, RH, and RS) and bedded with 1 of the 3 bedding materials for 60 d. We compared cost, moisture content, bacterial counts, and microbial composition of the 3 bedding materials, and investigated growth performance, health status, behavior, rumen fermentation, and blood parameters of bedded calves. The results showed that TD contained the fewest gram-negative bacteria and coliforms on d 1 and 30 and the lowest relative abundance of Staphylococcus throughout the experiment. The RH and TD bedding materials had the lowest cost. Calves in the TD and RS groups showed a higher dry matter intake, and final body weight and average daily gain in the TD and RS groups tended to be higher than in the RH group. Calves in the TD and RS groups had a lower disease incidence (diarrhea and fever), fewer antibiotic treatments, and lower fecal score than calves in the RH group. Higher contents of IgG, IgA, and IgM were observed in calves of the TD and RS groups than in calves of the RH group on d 10, indicating higher immune ability in TD and RS groups. Furthermore, TD bedding increased the butyric acid content in the calf's rumen, whereas RS bedding increased the acetate content, which might be attributed to the longer time and higher frequency of eating bedding material in the RS group. Considering all of the above indicators, we concluded that TD is the optimal bedding material for calves based on economics, bacterial count, microbial diversity, growth performance, and health status. Our findings provide a valuable reference for bedding material choice and calf farming.

Effects of Different Levels of Yucca Supplementation on Growth Rates, Metabolic Profiles, Fecal Odor Emissions, and Carcass Traits of Growing Lambs

Sixty male Awassi lambs were used to investigate the effects of dietary Yucca schidgera extract (YS) on the production, fecal and urinary odor emissions, and carcass traits of growing lambs fed complete pellets. Lambs were fed either a complete pelleted diet without yucca (control) or supplemented with 300 or 600 mg YS/kg dry matter (DM) during the 84-day experiment. The weights and feed consumption of the lambs were measured weekly. Blood samples were taken on days 1, 28, 58, and 84, and ruminal fluid samples were collected on day 70. On day 90, the odor emissions from feces and urine were measured. On day 84, 12 lambs were slaughtered for the evaluation of carcass and meat quality. The final values for bodyweight, bodyweight gain, and feed efficiency of lambs fed the YS₃₀₀ diet were 3.40%, 6.64%, and 6.17%, respectively, higher (p < 0.05) than those fed the YS₆₀₀ diet. Additionally, the percentage of dressing, myofibril fragmentation index, and ruminal isovalerate percentage of lambs treated with YS₆₀₀ were higher than those treated with YS₃₀₀. Compared with the control, the addition of yucca reduced odor emissions from feces and urine. In conclusion, dietary YS₃₀₀ had no additional benefits on growth rate, feed efficiency, and carcass traits, while dietary YS₆₀₀ improved fecal and urinary odors.

Selection of Forage Resources by Juvenile Goats in a Cafeteria Trial: Effect of Browsing Experience, Nutrient and Secondary Compound Content

Simple Summary

Grazing/browsing goats ingest a diverse diet selected from the forage resources available in the range/paddock intending to meet their nutritional requirements. Intake and selection of any given forage can be modified by several factors, such as its nutrient content, including secondary compounds, as well as its biomass availability in the environment. The animal’s previous browsing experience can also be an important factor driving intake and selection. Therefore, the present study evaluated all these factors as well as their interaction. The results showed that the goats’ browsing experience guided the selection and intake towards those forage resources of better nutritional quality when there was no restriction in forage supply, as is the case for cafeteria trials. Goats with browsing experience showed their ability to limit secondary compounds and optimize their selection and intake for plants with better digestibility. This cafeteria protocol made it possible to identify the selection and consumption pattern of plant species with limited availability in the natural vegetation. This methodology could help identifying the forage resources that may be useful for small ruminant feeding, versus those resources that are not consumed by goats despite having a suitable chemical composition and in vitro digestibility or a high abundance.

Abstract

We evaluated the effect of browsing experience, nutritional quality and secondary compounds of forage resources, and the interaction between these factors on the selection and intake of goats in a cafeteria trial. Twelve juvenile Criollo goats from 7 to 9 months of age, weighing 22 ± 3 kg, were divided into two groups: (a) browser goats group (n = 6, BG), and (b) naïve goats group (n = 6, NG), formed according to their previous browsing experience (with and without, respectively). Animals were housed in individual pens. The cafeteria experiment lasted 21 days considering pen adaptation, foliage adaptation, and measurements, which included the selection index (SI) of experimental forage resources (Chesson’s alpha) and their dry matter intake (DMI/Kg^0.75), using a multiple Latin square design. Furthermore, correlation and regression analyses were used to assess the relationship between the aforementioned factors. The NG did not show any selection pattern, while the BG selected Piscidia piscipula and Senegalia gaumeri (p = 0.0002). The BG consumed smaller amounts of secondary compounds compared to NG (p = 0.0001). In the BG, the flavonoids affected negatively their selection (R² = 97.51, p = 0.0001), while the DMI was affected by in vitro DM digestibility and flavonoids (R² = 99.85; p = 0.0001). For the NG, the crude protein and organic matter contents were associated with DMI, but none had a significant relationship with SI. The BG selected and consumed forages with suitable nutritional quality avoiding those with high content of secondary compounds such as flavonoids. Conversely, NG did not show a clear pattern for their selection or intake.

Evaluating the impact of feeding dried distillers grains with solubles on Boer goat growth performance, meat color stability and antioxidant capacity

A total of 72 male Boer goat kids (21.7 ± 0.5 kg) were fed for 21 d with 3 kids per pen and 12 pens per treatment. Dietary treatments were: 0% inclusion of dried distillers grains with solubles (DDGS; 0% DDGS) or 33% DDGS inclusion (33% DDGS) and were provided ad libitum. Goats and feeders were weighed weekly to collect body weights (BW) and determine feed disappearance in order to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). At the conclusion of the feeding study, a subset (n = 30; 2–3 goats from each pen representing six6 pens per treatment) of goats were harvested, carcasses evaluated, and loins were fabricated into 2.54 cm chops. Goat chop discoloration was evaluated by trained panelists and measured for L*, a*, and b* values on days 0, 4, 7, and 10 under retail display conditions. Samples were collected and analyzed for lipid oxidation, fatty acid profile, and hydrophilic and lipophilic antioxidant capacity. No evidence of differences was observed for final BW, ADFI, G:F, and carcass characteristics (P > 0.05). However, goats fed the 0% DDGS diet had greater ADG compared with those fed a diet containing 33% DDGS (P = 0.05). Overall, visual evaluation of discoloration, L*, a*, and b* as well as lipid oxidation data confirmed that feeding 33% DDGS to goats had no effect on goat chop discoloration and lipid oxidation (P > 0.10). However, all chops demonstrated a display effect, which they increased in visual discoloration and lipid oxidation and decreased in a* and b* values (P < 0.01) over the entirety of the 10-d period of retail display, regardless of the dietary treatments. As expected, feeding 33% DDGS to goats decreased relative percentage of multiple and total monounsaturated fatty acids, but increased relative percentage of multiple and total polyunsaturated fatty acids (PUFA; P < 0.05). The antioxidant capacity measurements showed no treatment difference in the hydrophilic portion (P > 0.10), but chops from the 33% DDGS treatment had greater lipophilic antioxidant activity compared with the 0% DDGS chops (P < 0.05). In conclusion, including 33% DDGS to the diet may negatively impact goat growth performance, but did not impact any carcass characteristics. Feeding a diet with 33% DDGS resulted in an increase in the PUFA content of goat chops but did not appear to impact meat color or lipid oxidation. The supposed negative consequence from increased PUFA is likely counterbalanced by the increased antioxidant capacity in the lipid component of meat, resulting in no difference in meat shelf-life.

Milk Production Responses and Digestibility of Dairy Buffaloes (Bubalus bubalis) Partially Supplemented with Forage Rape (Brassica napus) Silage Replacing Corn Silage

Simple Summary

To develop alternative silage resources, we employed buffaloes as an animal model to evaluate the possibility and effects of forage rape silage in the dairy buffalo diet. We comprehensively assessed the nutrition value of forage rape silage by the apparent total-tract digestibility, rumen fermentation characteristics, blood metabolism and milk composition of lactating buffaloes. Our current results showed that the inclusion of forage rape silage in diets improved the milk quality, such as milk protein, milk fat, and total solid percentage. Furthermore, partial supplementation of forage rape silage also promotes buffaloes’ dry matter intake. These may be related to the favorable physiological and metabolic changes induced by the forage rape silage. Thus, our current data show the applicability of forage rape silage as a good feed resource for ruminants.

Abstract

Worldwide, silage is considered the main component in dairy animal diets; however, this portion is mainly dominated by corn silage, which raises availability challenges in some agricultural production systems. The present study evaluated a partial replacement of corn silage with forage rape silage (FRS) and its effect on feed intake, nutrient digestibility, rumen fermentation, milk production, and blood metabolites in buffalo. Thirty-six lactating buffaloes were randomly assigned to four different groups, according to supplementation of FRS (only corn silage, FRS₀) or with 15% (FRS₁₅), 25% (FRS₂₅), and 35% (FRS₃₅) of forage rape silage instead of corn silage. The results showed that, compared to corn silage, forage rape silage has a lower carbohydrate but a higher protein concentration. The buffalo intake of dry matter and organic matter were improved linearly with the FRS increasing in the diet. The apparent total-tract digestibility (ATTD) of dry matter, organic matter, nitrogen, neutral detergent fiber, and acid detergent fiber also increased by the FRS supplementation compared with FRS₀. Conversely, FRS supplementation decreased the propionic, butyric, and valeric acid contents and increased the acetic:propionic ratio and microbial protein content. Furthermore, FRS inclusion led to a significantly higher milk urea and non-fat milk solid content, higher blood glucose, total globulins, blood urea nitrogen, and lower blood high-density lipoprotein. These results suggested that FRS has high a nutritional value and digestibility, is a good feed resource, and showed favorable effects when supplemented with dairy buffalo ration.

Effects of Ursolic Acid on Intestinal Health and Gut Bacteria Antibiotic Resistance in Mice

Ursolic acid (UA), a natural pentacyclic triterpenoid, has been widely reported to exert anti-oxidant and anti-inflammatory properties. However, the effects of UA on the intestinal homeostasis and gut microbiota were rarely explored. The aim of the present study was to investigate the effects of UA on intestinal health and gut microflora antibiotic-resistance in antibiotic-exposed mice. Kunming mice (n = 80) were randomly allocated into three groups and fed with one of the following diets, respectively: Cont group (n = 20), the basal diet; UA group (n = 20), the basal diet supplemented with 150 mg/kg UA; Tet group (n = 40), the basal diet supplemented with 659 mg/kg chlortetracycline. After 14 days, 10 mice in each group were euthanatized and the remaining 30 mice in the Tet group were randomly allocated into three sub-groups (n = 10 per group) as follows: the Tet group which were kept feeding a Tet diet for 14 days; the Natural Restoration (NatR) group which received a basal diet for 14 days; and the UA therapy (UaT) group which fed a basal diet supplemented with 150 mg/kg UA for 14 days. Throughout the experiment, the weight and the food intake of each mouse were recorded once weekly. Serum LPS and diamine oxidase (DAO), jejunal morphology, jejunal tight junction proteins and nutrient transporters, colonic inflammatory cytokines, gut microbiota and its antibiotic resistance gene (ARG) were examined at euthanasia. The results showed that UA treatment significantly increased average daily food intake (ADFI) of mice. Notably, UA increased the jejunal villi height, decreased the jejunal crypt depth and promoted the expression of jejunum nutrient transporters. UaT group had higher villi height, lower crypt depth and higher nutrient transporter mRNA expression in jejunum than NatR group. Besides, UA decreased serum DAO content, upregulated mRNA expression of ZO-1, claudin-1 and occludin and downregulated TNF-α and IL-6. The mRNA abundances of ZO-1, claudin-1 and occludin and TNF-α and IL-6 in UaT group were, respectively upregulated and downregulated than NatR group. Furthermore, an analysis of 16S rDNA sequences demonstrated that UA increased the abundance of beneficial bacteria in the gut. And the results of ARG test showed that UA downregulated the expression of antibiotic-induced resistance genes. The UaT group inhibited the increase of harmful bacteria abundance and suppressed the mRNA abundances of ARG compared to the NatR group. In conclusion, considering the positive effects of UA on the growth performance and intestinal mucosal barrier, we anticipate that these findings could be a stepping stone for developing UA as a novel substitute of antibiotics.

Nutritional Aspects of Ecologically Relevant Phytochemicals in Ruminant Production

This review provides an update of ecologically relevant phytochemicals for ruminant production, focusing on their contribution to advancing nutrition. Phytochemicals embody a broad spectrum of chemical components that influence resource competence and biological advantage in determining plant species' distribution and density in different ecosystems. These natural compounds also often act as plant defensive chemicals against predatorial microbes, insects, and herbivores. They may modulate or exacerbate microbial transactions in the gastrointestinal tract and physiological responses in ruminant microbiomes. To harness their production-enhancing characteristics, phytochemicals have been actively researched as feed additives to manipulate ruminal fermentation and establish other phytochemoprophylactic (prevent animal diseases) and phytochemotherapeutic (treat animal diseases) roles. However, phytochemical-host interactions, the exact mechanism of action, and their effects require more profound elucidation to provide definitive recommendations for ruminant production. The majority of phytochemicals of nutritional and pharmacological interest are typically classified as flavonoids (9%), terpenoids (55%), and alkaloids (36%). Within flavonoids, polyphenolics (e.g., hydrolyzable and condensed tannins) have many benefits to ruminants, including reducing methane (CH4) emission, gastrointestinal nematode parasitism, and ruminal proteolysis. Within terpenoids, saponins and essential oils also mitigate CH4 emission, but triterpenoid saponins have rich biochemical structures with many clinical benefits in humans. The anti-methanogenic property in ruminants is variable because of the simultaneous targeting of several physiological pathways. This may explain saponin-containing forages' relative safety for long-term use and describe associated molecular interactions on all ruminant metabolism phases. Alkaloids are N-containing compounds with vast pharmacological properties currently used to treat humans, but their phytochemical usage as feed additives in ruminants has yet to be exploited as they may act as ghost compounds alongside other phytochemicals of known importance. We discussed strategic recommendations for phytochemicals to support sustainable ruminant production, such as replacements for antibiotics and anthelmintics. Topics that merit further examination are discussed and include the role of fresh forages vis-à-vis processed feeds in confined ruminant operations. Applications and benefits of phytochemicals to humankind are yet to be fully understood or utilized. Scientific explorations have provided promising results, pending thorough vetting before primetime use, such that academic and commercial interests in the technology are fully adopted.

Evaluation of origanum oil, hydrolysable tannins and tea saponin in mitigating ruminant methane: In vitro and in vivo methods

The objective of this study was to investigate the effects of origanum oil (ORO), hydrolysable tannins (HYT) and tea saponin (TES) on methane (CH₄) emission, rumen fermentation, productive performance and gas exchange in sheep by using in vitro and in vivo methods. The ORO, HYT and TES additive levels were normalized per kg dry matter (DM) in both in vitro and in vivo experiments: ORO‐0, 10, 20 and 40 ml/kg; HYT‐0, 15, 30 and 60 g/kg; and TES‐0, 15, 30 and 60 g/kg, respectively. During in vitro incubation, 40 ml/kg ORO linearly decreased CH₄ emission (p < 0.05); 20 and 40 ml/kg ORO cubically decreased carbon dioxide (CO₂) production (p < 0.05), and rumen pH was cubically raised with the increasing ORO additive level (p < 0.01). The 60 g/kg HYT cubically decreased CH₄ production (p < 0.05). The pH of 60 g/kg HYT was higher than that of 15 and 30 g/kg (p < 0.01); the pH of 20 g/kg TES was higher than that of 5 g/kg (p < 0.05). In the in vivo experiments, 40 ml/kg ORO inhibited dry matter intake (p < 0.01) cubically and reduced average daily gain (ADG) and feed conversion ratio (FCR) cubically (p < 0.05), and 20 or 40 ml/kg ORO linearly decreased CH₄ production based on per day or metabolic weight (W^0.75) (p < 0.05). Both 30 and 60 g/kg HYT linearly inhibited CH₄ emission on the bases of per day and W^0.75 (p < 0.05). The 20 g/kg TES improved the apparent digestibility of crude protein (p < 0.05), 10 and 20 g/kg of TES decreased CH₄ emission (p < 0.05), and 5 g/kg of TES reduced O₂ consumption and CO₂ production (p < 0.05). In conclusion, these three plant extracts all showed the abilities on mitigating CH₄ emission of sheep with appropriate additive ranges.

Mitigation of Rumen Methane Emissions with Foliage and Pods of Tropical Trees

Simple Summary

Methane produced by enteric fermentation contributes to the emission of greenhouse gases (GHG) into the atmosphere. Methane is one of the GHG arising from anthropogenic activities with the greater contribution to global warming. This paper provides a brief introduction to the potential use of tropical foliage trees, pods, and secondary metabolites to reduce methane emissions from ruminant supply chains. A better knowledge of the available strategies for efficient foliage use in the tropics is essential in order to ensure increasing livestock production while preserving the environment. The mitigation of rumen methane production through the use of the foliage and metabolites of tropical trees represents an interesting challenge for scientists working in the field of ruminant nutrition.

Abstract

Methane produced by enteric fermentation contributes to the emission of greenhouse gases (GHG) into the atmosphere. Methane is one of the GHG resulting from anthropogenic activities with the greater global warming contribution. Ruminant production systems contribute between 18% and 33% of methane emissions. Due to this, there has been growing interest in finding feed alternatives which may help to mitigate methane production in the rumen. The presence of a vast range of secondary metabolites in tropical trees (coumarins, phenols, tannins, and saponins, among others) may be a valuable alternative to manipulate rumen fermentation and partially defaunate the rumen, and thus reduce enteric methane production. Recent reports suggest that it is possible to decrease methane emissions in sheep by up to 27% by feeding them saponins from the tea leaves of Camellia sinensis; partial defaunation (54%) of the rumen has been achieved using saponins from Sapindus saponaria. The aim of this review was to collect, analyze, and interpret scientific information on the potential of tropical trees and their secondary metabolites to mitigate methane emissions from ruminants.

Productive behavior in growing kid goats and methane production with the inclusion of chokecherry leaf (Prunus salicifolia)

Currently for the reduction of methane (CH4) emissions are using fodder rich in condensed tannins, however, not yet known exactly how they act in the rumen is not yet clear. The objective of this study was to evaluate the effect of the inclusion of leaves of Prunus salicifolia (PS, 0%, 15%, and 30%) on the productive behavior of growing kid goats, methane production, nutritional value, fermentation, and ruminal digestibility through an in vivo and in vitro study was performed. Diets were administered ad libitum to 6 Saanen kids with live weight (LW) of 12.25 ± 2.25 kg. Three levels of inclusion were used in a diet based on ground corn grain, soybean meal, corn stover, and oat hay in substitution with P. salicifolia leaves. The in vivo productive behavior was determined, as well as the fermentation kinetics, in vitro gas production, CH4 and hydrogen (H2) in an in vitro system was determined. For the in vivo study, we used a 3 × 3 Latin square design in in vivo study and an analysis of variance with three replications for in vitro gas production. The inclusion of 30% increased (P = 0.0011) dry matter intake (DMI 589.33 g/day) compared to the control group (418.80 g/day). The highest N excretion (feces and urine) (P < 0.001) was for T0, in addition to presenting a negative nitrogen balance compared with T15 and T30. The production of CH4 (mM)/g DM incubated, and CH4 (mM)/g DM fermented, CH4 (mM/day), and H2 was lower (P < 0.05) in T30 than T0 and T15. CH4 (mM)/day was lower (P < 0.036) in T130 (283 mM/day) compared with T0 (407 mM/day) P. salicifolia is a forage that helps to reduce the production of methane and can be included in the diets of growing kid goats in amounts less than 30% without affecting production performance.

Effect of herbal feed additives containing saponins on rumen fermentation pattern

Macrotyloma uniflorum (kulthi) seeds, Asparagus racemosus (shatavari) roots or Acacia concina (shikakai) pods were supplemented to total mixed rations (TMR) @ 0-3% (on DM basis) to assess the impact of herbal feed additives (HFAs) on the in vitro rumen fermentation pattern. The saponin content and 2, 2-diphenyl-1-picrylhydrazyl- hydrate (DPHH) antioxidant activity was highest in A. racemosus than other HFAs. But total phenols, non tannin phenols, true tannins, condensed tannins, vitamin C and flavanoid contents were highest inM. uniflorum and lowest in A. concina. The dose/level of supplementation of HFAs, irrespective of their nature did not affect net gas production (NGP) and availability of metabolizable energy (ME) from TMR, but digestibility of nutrients and partitioning factor (PF) decreased in comparison to the unsupplemented group. The total and individual volatile fatty acids (VFAs) production; and acetate to propionate ratio was improved when the TMR was supplemented with HFAs at 1% level. The methane and ammonia-N production was depressed at 2% level as compared to control group. Irrespective of the dose, the total VFAs, acetate, and propionate production was higher while ammonia-N decreased in M. uniflorum supplemented TMR than other HFAs supplemented groups. Methane production from the TMR was comparable in the diet supplemented with different HFAs, however, diet supplemented with M. uniflorum resulted in lower methane production. Amongst the tested HFAs, M. uniflorum was a richer source of most of the bio-active compounds. Based on in vitro fermentation parameters, M. uniflorum supplemented to TMR @ 2% gave the best results.

Effect of herbal feed additive containing saponins on the performance of goat kids

This study was taken up to assess the effect of supplementing Macrotyloma uniflorum (an herbal feed additive; HFA) on nutrient utilization, productive performance and meat quality of goat kids. Eight male Beetal goat kids (5 months old; body weight 14.05±0.41 kg) divided in to 2 equal groups were either fed a control total mixed ration (TMR) containing concentrate and green fodder in 50: 50 ratio on DM basis or control TMR supplemented with M. uniflorum @ 2.0% of DM intake for 90 days. Simultaneously, rumen studies were conducted on three rumen fistulated male bucks. Higher total-N, trichloroacetic acid precipitable nitrogen (TCA-N) and nonprotein nitrogen (NPN) concentration was observed in strained rumen contents (SRC) of animals fed M. uniflorum supplemented TMR as compared to control. Supplementation of TMR with M. uniflorum increased the production of volatile fatty acids (VFAs) and fermentation efficiency while efficiency of conversion of hexose to methane decreased in M. uniflorum supplemented TMR in comparison to control TMR. Nutrients digestibility, N-retention, urinary excretion of purine derivatives, blood profile and average daily gain were comparable in both the groups. The higher ready to cook (RTC) carcass percentage resulted in higher RTC carcass yield in M. uniflorum supplemented group. Overall, the weight of most of the primal cuts expressed as per cent of dressed weight improved in goat kids fed TMR supplemented with M. uniflorum as compared to those fed control diet. Hence, the higher weight of most of the primal cuts can be achieved in Beetal goat kids by supplementing the TMR with M. uniflorum (kulthi) at 2% of DM intake.

Effect of tree foliage supplementation of tropical grass diet on in vitro digestibility and fermentation, microbial biomass synthesis and enteric methane production in ruminants

The objective of this study was to evaluate the influence of tree foliage species supplemented in ruminant diets based on Pennisetum purpureum on the in vitro digestibility and fermentation, microbial biomass synthesis and enteric methane production. Seven experimental diets were evaluated, including a control treatment based on P. purpureum (PT) grass, and six additional treatments supplemented with 30.0% foliage from Neomillspaughia emargiata (NE), Tabernaemontana amygdalifolia (TA), Caesalpinia gaumeri (CG), Piscidia piscipula (PP), Leucaena leucocephala (LL) and Havardia albicans (HA). A randomised complete block design repeated in two periods (block) was used. The highest gas production (P < 0.05) was recorded in treatments TA and PT (237 and 228 mL g-1, respectively). The highest in vitro digestibility of dry matter (IVDMD) and organic matter (IVOMD) (P < 0.05) was recorded in the control treatment PT (57.9% and 66.1%, respectively). Treatments LL, NE, TA and PP promoted greater microbial biomass synthesis (290, 223, 220 and 213 mg g-1, respectively) (P < 0.05). The proportion of propionic acid also increased in these latter treatments and in treatments CG and HA (P < 0.05). Additionally, treatments LL, PP, NE and TA decreased methane production (25.8, 29.5, 30.6 and 31.8 L kg-1 of digested dry matter, respectively). In conclusion, supplementation with L. leucocephala, P. piscipula, N. emargiata and T. amygdalifolia in ruminant diets based on P. purpureum is one feed alternative that can promote greater efficiency and synthesis of microbial biomass, increase the proportions of propionic and butyric acid and decrease the production of enteric methane by 15.6 to 31.6%.

Effects of Tea Saponin Supplementation on Nutrient Digestibility, Methanogenesis, and Ruminal Microbial Flora in Dorper Crossbred Ewe

Simple Summary

Greenhouse gas emissions are a serious cause of global warming and climate change, and have become a common focus for all countries. Methane has been proven the second most commonly occurring greenhouse gas. Ruminants have been blamed for substantially contributing to methane emissions. Supplementation with tea saponin (TS) effectively decreased methane emissions and nitrogen emissions. It is not only beneficial for environmental protection, but also has potential economic benefits.

Abstract

Two experiments were conducted using Dorper × thin-tailed Han crossbred ewes. In experiment 1, eighteen ewes were randomly assigned to two dietary treatments (a basal diet, or the same basal diet supplemented with 2.0 g tea saponin (TS)/head/day) to investigate the effects of TS supplementation on nutrient digestibility and methane emissions. In experiment 2, six ewes with ruminal cannulae were assigned to the same two dietary treatments as in experiment 1 to investigate the effects of TS supplementation on rumen fermentation and microbial flora. TS supplementation increased the apparent digestibility of organic matter (OM) (p = 0.001), nitrogen (N) (p = 0.036), neutral detergent fibre (NDF) (p = 0.001), and acid detergent fibre (ADF) (p < 0.001). Urinary N (p = 0.001) and fecal N (p = 0.036) output were reduced, and N retention (p = 0.001) and nitrogen retention/nitrogen intake (p = 0.001) were increased. Supplementary TS did not decrease absolute methane emissions (p = 0.519) but decreased methane emissions scaled to metabolic bodyweight by 8.80% (p = 0.006). Ammonia levels decreased (p < 0.001) and total volatile fatty acid levels increased (p = 0.018) in response to TS supplementation. The molar proportion of propionate increased (p = 0.007), whereas the acetate:propionate ratio decreased (p = 0.035). Supplementation with TS increased the population of Fibrobacter succinogenes (p = 0.019), but the population of protozoans tended to decrease (p = 0.054). Supplementation with TS effectively enhanced the apparent digestibility of OM, N, NDF, and ADF, and decreased methane emissions scaled to metabolic bodyweight.

The particulate passage rate, nutrient composition and fermentation characteristics across gastrointestinal tracts in lactating dairy cows fed three different forage source diets

This study was conducted to investigate the particulate passage rate, nutrient characteristics and fermentation parameters across the gastrointestinal tract (GIT) in lactating dairy cows fed cereal straws in comparison with alfalfa hay. Eighteen multiparous Holstein cows were randomly assigned to one of three experimental diets consisting of 55% concentrate, 15% corn silage and 30% different forage sources as follows (% of dry matter [DM]): (i) 23% alfalfa hay and 7% Chinese wild rye hay (AH); (ii) 30% corn stover (CS); and (iii) 30% rice straw (RS). The Cr-mordanted corn silage-neutral detergent fibre was used to estimate the passage flow at week 14. After 14-week feeding, the animals were slaughtered to collect the gastrointestinal digesta. Dietary forage sources had little effect on the fractional passage rates in the rumen (range from 5.05 to 6.25%/hr) or hindgut (range from 4.49 to 5.24%/hr). Total volatile fatty acid (VFA) concentration in the caecum was highest, followed by the rumen, colon and rectum, and the lowest in the abomasum and duodenum, indicating that the large intestines, especially caecum, are the important positions for carbohydrate degradation. Greater proportion of propionate and butyrate and lower acetate were found in the AH compared to CS or RS in colon, but higher acetate in abomasum was found in the cows fed CS or RS compared to AH. In conclusion, cereal straw diets did not change the particulate passage rate in the rumen and hindgut which might be mainly due to the similar DM intake among these three diets. Different forage source diets significantly changed VFA proportion in the abomasum and colon, indicating the existence of different digestion or absorption rates in these tracts among the experimental diets.

Nutrient intake, digestibility and performance of Gaddi kids supplemented with tea seed or tea seed saponin extract

Objective

An experiment was conducted to determine the nutrient intake, digestibility, microbial protein synthesis, haemato-biochemical attributes, immune response and growth performance of Gaddi kids fed with oat fodder based basal diet supplemented with either tea seed or tea seed saponin (TSS) extract.

Methods

Eighteen male kids, 7.03±0.16 months of age and 19.72±0.64 kg body weight, were distributed into three groups, T₀ (control), T₁, and T₂, consisting of 6 animals each in a completely randomized design. The kids were fed a basal diet consisting of concentrate mixture and oat fodder (50:50). Animals in group III (T₂) were supplemented with TSS at 0.4% of dry matter intake (DMI), and group II (T₁) were supplemented with tea seed at 2.6% of DMI to provide equivalent dose of TSS as in T₂. Two metabolism trials were conducted, 1st after 21 days and 2nd after 90 days of feeding to evaluate the short term and long term effects of supplementation.

Results

The tea seed (T₁) or TSS (T₂) supplementation did not affect DMI as well as the digestibility of dry matter, organic matter, crude protein, neutral detergent fibre, and acid detergent fibre. Nutritive value of diet and plane of nutrition were also comparable for both the periods. However, the average daily gain and feed conversion ratio (FCR) were improved (p<0.05) for T₁ and T₂ as compared to T₀. The microbial protein supply was also higher (p<0.05) for T₁ and T₂ for both the periods. There was no effect of supplementation on most blood parameters. However, the triglyceride and low density lipoprotein cholesterol levels decreased (p<0.05) and high density lipoprotein-cholesterol level increased (p<0.05) in T₂ as compared with T₀ and T₁. Supplementation also did not affect the cell mediated and humoral immune response in goats.

Conclusion

Tea seed at 2.6% of DMI and TSS at 0.4% DMI can be fed to Gaddi goats to improve growth rate, FCR and microbial protein synthesis.

Effects of tea seed saponin supplementation on physiological changes associated with blood methane concentration in tropical Brahman cattle

A 59-day experiment compared the effects of increasing tea seed (Camellia sinensis L.) saponin (TSS) supplementation on dry matter intake (DMI), liveweight (LW), rumen fermentation, methanogenesis, blood biochemistry and animal tolerance. Six, 10, 15, 20, 25 and 30 g of powder TSS were dissolved during 5, 7, 4, 3, 3 and 2 days, respectively, and infused into the rumen of four rumen-cannulated Brahman steers (234 ± 13.6 kg LW; least-squares means ± s.e.m.) or mixed in the basal diet [BD: 0.15 Rhodes grass (Chloris gayana) hay plus a high-grain feed (0.85)] of two non-cannulated (253 ± 19.3 kg) steers. Overall, DMI was not affected, by the sequential infusion of TSS (5.3 ± 0.15 kg) or addition to the BD (5.4 ± 0.18 kg), but relative to all diets, 6 g of TSS supplementation reduced DMI (P < 0.05), while the administration above 30 g of the supplement was associated with significantly (P < 0.001) reduced DMI, scours and bloat disorders. Clinical symptoms disappeared 8 days after withdrawal of the supplement. LW increased with time (P < 0.05) and the final LW was similar for cannulated (258 ± 13.6 kg) and non-cannulated (276 ± 19.3 kg) steers. Saponin supplementation reduced total volatile fatty acid (VFA) concentration (P < 0.05), modified pattern of individual molar VFA concentrations and moderately increased ruminal pH (P < 0.05). Cannulated and non-cannulated steers fed the BD had similar daily (g) methane or yield (CH4 g/kg DMI) emissions while in respiratory chambers. However, compared with cannulated (8.0 ± 1.20 ng/mL) animals, the addition of 30 g of TSS in the BD increased (P < 0.01) blood CH4 concentration in non-cannulated (15.6 ± 1.74 ng/mL) animals. Diets supplemented with 30 g of TSS were associated with higher chloride (P < 0.01) and alkaline phosphatase (P < 0.05) blood concentrations, and lower serum concentrations of potassium and urea nitrogen (P < 0.01), iron and total lipase (P < 0.05), than was the BD. It was concluded that higher levels of TSS supplement may evoke physiological changes in the animal. However, the potential CH4 mitigation effect of this form of saponin in tropical cattle needs further investigation, alongside the derived response of the rumen microbial ecology to the tested range of supplementation.

Meta-analysis on Methane Mitigating Properties of Saponin-rich Sources in the Rumen: Influence of Addition Levels and Plant Sources

Saponins have been considered as promising natural substances for mitigating methane emissions from ruminants. However, studies reported that addition of saponin-rich sources often arrived at contrasting results, i.e. either it decreased methane or it did not. The aim of the present study was to assess ruminal methane emissions through a meta-analytical approach of integrating related studies from published papers which described various levels of different saponin-rich sources being added to ruminant feed. A database was constructed from published literature reporting the addition of saponin-rich sources at various levels and then monitoring ruminal methane emissions in vitro. Accordingly, levels of saponin-rich source additions as well as different saponin sources were specified in the database. Apart from methane, other related rumen fermentation parameters were also included in the database, i.e. organic matter digestibility, gas production, pH, ammonia concentration, short-chain fatty acid profiles and protozoal count. A total of 23 studies comprised of 89 data points met the inclusion criteria. The data obtained were subsequently subjected to a statistical meta-analysis based on mixed model methodology. Accordingly, different studies were treated as random effects whereas levels of saponin-rich source additions or different saponin sources were considered as fixed effects. Model statistics used were p-value and root mean square error. Results showed that an addition of increasing levels of a saponin-rich source decreased methane emission per unit of substrate incubated as well as per unit of total gas produced (p<0.05). There was a decrease in acetate proportion (linear pattern; p<0.001) and an increase in propionate proportion (linear pattern; p<0.001) with increasing levels of saponin. Log protozoal count decreased (p<0.05) at higher saponin levels. Comparing between different saponin-rich sources, all saponin sources, i.e. quillaja, tea and yucca saponins produced less methane per unit of total gas than that of control (p<0.05). Although numerically the order of effectiveness of saponin-rich sources in mitigating methane was yucca>tea>quillaja, statistically they did not differ each other. It can be concluded that methane mitigating properties of saponins in the rumen are level- and source-dependent.

Effect of supplementation with saponins from Yucca schidigera on ruminal methane production by Pelibuey sheep fed Pennisetum purpureum grass

The aim of the work was to determine the effect of increasing concentrations of saponins from Yucca schidigera in the diet on voluntary intake, rumen fermentation and methane (CH4) production in Pelibuey sheep fed a tropical grass Pennisetum purpureum. Five male sheep (32.2 ± 1.1 kg liveweight) were fed chopped P. purpureum grass in a 5 × 5 Latin square design. Sheep were supplemented with 0.0, 1.5, 3.0, 4.5 or 6.0 g per day of saponins from Y. schidigera mixed with ground corn, before the grass was offered. Feed intake, feed refusal and total faecal output were recorded for 20 days of the adaptation period and 5 days of the experimental period. Apparent digestibility of dry matter (DMD), organic matter (OMD), neutral detergent fibre (NDFD) and acid detergent fibre (ADFD) were determined. Ruminal methane emission was estimated using stoichiometric balance and the molar proportion of volatile fatty acids was determined by gas chromatography. Voluntary intake, DMD, OMD, NDFD, ADFD, volatile fatty acids and CH4 emission were not affected (P > 0.05) by increasing inclusion levels of saponins in the ration of sheep. Nonetheless, CH4 production increased as the voluntary intake of NDF augmented. Addition of 6 g of saponins per day as a supplement to Pelibuey sheep fed a tropical grass did not affect voluntary intake and digestibility of DM, OM, NDF and ADF, or ruminal methane production.

Effects of tea saponins on rumen microbiota, rumen fermentation, methane production and growth performance--a review

Reducing methane emission from ruminant animals has implications not only for global environmental protection but also for efficient animal production. Tea saponins (TS) extracted from seeds, leaves or roots of tea plant are pentacyclic triterpenes. They have a lasting antiprotozoal effect, but little effect on the methanogen population in sheep. There was no significant correlation between the protozoa counts and methanogens. The TS decreased methanogen activity. It seems that TS influenced the activity of the methanogens indirectly via the depressed ciliate protozoal population. The TS addition decreased fungal population in the medium containing rumen liquor in in vitro fermentation, but no such effect was observed in the rumen liquor of sheep fed TS. Tea saponins had a minor effect on the pattern of rumen fermentation and hence on nutrient digestion. When added at 3 g/day in diets, TS could improve daily weight gain and feed efficiency in goats. No positive associative effect existed between TS and disodium fumarate or soybean oil on methane suppression. Inclusion of TS in diets may be an effective way for improving feed efficiency in ruminants.

Prevention of rotavirus infections in vitro with aqueous extracts of Quillaja Saponaria Molina

BACKGROUND

Rotavirus is the leading cause of severe diarrhea disease in newborns and young children worldwide, estimated to be responsible for over 300,000 childhood deaths every year, mostly in developing countries. Rotavirus-related deaths represent approximately 5% of all deaths in children younger than 5 years of age worldwide. Saponins are readily soluble in water and are approved by the US FDA for inclusion in beverages intended for human consumption. The addition of saponins to existing water supplies offers a new form of intervention into the cycle of rotavirus infection. We believe that saponins will 'coat' the epithelium of the host's small intestine and prevent attachment of rotavirus.

DISCUSSION

This experiment provides in vitro data for the possibility of including saponin in drinking water to prevent infections of rotavirus. We demonstrate that microgram amounts of extract, while exhibiting no cell cytotoxicity or direct virucidal activity, prevent rotavirus from infecting its host cells. In addition, the presence of residual amounts of extract continue to block viral infection and render cells resistant to infection for at least 16 h after the removal of the extract from the cell culture media.

CONCLUSION

We demonstrate that two Quillaja extracts possess strong antiviral activity at concentrations more than 1000-fold lower than concentrations exhibiting cell cytotoxicity. Extract concentrations as high as 1000 μg/ml are not cytotoxic, but concentrations as low as 1.0 μg/ml are able to block rotavirus and reovirus attachment and infection.

A new perspective on the use of plant secondary metabolites to inhibit methanogenesis in the rumen

Recently, greenhouse gas emissions have been of great concern globally. Ruminant livestock due to production of methane during normal fermentation in the rumen contributes substantially to the greenhouse effects. During the recent decade, a paradigm shift has been initiated whether plant secondary metabolites (PSM) could be exploited as natural safe feed additives alternative to chemical additives to inhibit enteric methanogenesis. More than 200,000 defined structures of PSM have been known. Some plants or their extracts with high concentrations of bioactive PSM such as saponins, tannins, essential oils, organosulphur compounds, flavonoids and many other metabolites appear to have potential to inhibit methane production in the rumen. The possible mechanisms and effects of many PSM on rumen methanogenesis are not clearly understood. Saponins may decrease methanogenesis through the inhibition of rumen protozoa and in turn may suppress the numbers and activity of methanogens. Although the direct effect of saponins on methanogens has not been demonstrated, saponins might inhibit methanogens at high doses. Tannins may inhibit the methanogenesis directly and also via inhibition of protozoal growth. Essential oils, organosulphur compounds and flavonoids appear to have direct effects against methanogens, and a reduction of protozoa associated methanogenesis probably plays a minor role for these metabolites. The chemical structure and molecular weight of the PSM and chemical composition of diets dependent upon the different feeding regimes may influence the effects of PSM on methane production. Although PSM may negatively affect nutrient utilization, there is evidence that methanogenesis could be suppressed without adversely affecting rumen fermentation, which could be exploited to mitigate methane emission in ruminants.