Anuraga Jayanegara

Meta-analysis of the relationship between dietary tannin level and methane formation in ruminants from in vivo and in vitro experiments

A meta-analysis was conducted to evaluate the extent to which dietary tannin level is related to methane emissions from ruminants. Data from a total of 30 experiments comprising 171 treatments were entered in a database. In vitro batch culture and in vivo measurements were distinguished as experimental approaches. With any approach, methane declined when dietary tannins increased. The in vitro approach predicted the in vivo response quite accurately. However, in vitro, the response followed a quadratic response pattern (R(2) = 0.66; lower response with increasing tannin level), whereas in vivo, this decline was linear (R(2) = 0.29). This indicates that the in vitro batch culture is of limited accuracy for estimating effects at levels >100 g tannin/kg dry matter. The large variation in methane/digestible organic matter (OM) found at low tannin levels may explain contrasting literature reports. Methane reduction with tannins was associated with a reduced apparent digestion of OM, and especially fibre, but methane/apparently digestible OM declined also. The present findings are helpful as they identified an underlying general antimethanogenic effect of tannins across tannin sources and experimental conditions, thus allowing concentrating the search on sources with satisfactory palatability and low adverse effects on animal performance.

Significance of phenolic compounds in tropical forages for the ruminal bypass of polyunsaturated fatty acids and the appearance of biohydrogenation intermediates as examined in vitro

The purpose of the present study was to assess the influence of phenol-rich tropical ruminant feeds on the extent of ruminal biohydrogenation (BH) of polyunsaturated fatty acids (PUFA). Samples of 27 tropical forages (mainly tree and shrub leaves), characterised by different phenolic profiles, were incubated in vitro (n = 4 replicates) with buffered rumen fluid for 24 h using the Hohenheim gas test method. Linseed oil was added as a rich source of PUFA. In the plants, total extractable phenols (TEP), non-tannin phenols, condensedtannins, and fattyacids were determined. After terminating incubation, the fatty acid profile present in fermentation fluid (total syringe content) was analysed by gas chromatography. The relationship between TEP and the disappearance of a-linolenic acid from the incubation fluid was negative (R 2 = 0.48, P < 0.001), indicating that TEP reduced the ruminal BH of this PUFA. Similarly, TEP were negatively related with the disappearancesoflinoleicacid(R 2 =0.52,P <0.001)andoleicacid(R 2 =0.58,P <0.001).Theappearanceofrumenicacid, an important conjugated linoleic acid isomer, was positively correlated with TEP (R 2 = 0.30, P < 0.01), while the opposite result was seen with stearic acid (R 2 = 0.22,P <0.05). Leaves of avocado (Persea americana) were particularly interesting, because they changed the BH pattern at a moderate TEP content of 73 g/kg DM. It is concluded that, in the tropical feedstuffs investigated, TEP have an impact on ruminal fatty acid BH and are associated with an increased bypass of PUFA and the generation of conjugated linoleic acid.

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.

In vitro indications for favourable non-additive effects on ruminal methane mitigation between high-phenolic and high-quality forages

Feeding plants containing elevated levels of polyphenols may reduce ruminal CH₄ emissions, but at the expense of nutrient utilisation. There might, however, be non-additive effects when combining high-phenolic plants with well-digestible, high-nutrient feeds. To test whether non-additive effects exist, the leaves of Carica papaya (high in dietary quality, low in polyphenols), Clidemia hirta (high in hydrolysable tannins), Swietenia mahagoni (high in condensed tannins) and Eugenia aquea (high in non-tannin phenolics) were tested alone and in all possible mixtures (n 15 treatments). An amount of 200 mg DM of samples was incubated in vitro (24 h; 39°C) with buffered rumen fluid using the Hohenheim gas test apparatus. After the incubation, total gas production, CH₄ concentration and fermentation profiles were determined. The levels of absolute CH₄, and CH₄:SCFA and CH₄:total gas ratios were lower (P< 0·05) when incubating a combination of C. papaya and any high-phenolic plants (C. hirta, S. mahagoni and E. aquea) than when incubating C. papaya alone. Additionally, mixtures resulted in non-additive effects for all CH₄-related parameters of the order of 2-15 % deviation from the expected value (P< 0·01). This means that, by combining these plants, CH₄ in relation to the fermentative capacity was lower than that predicted when assuming the linearity of the effects. Similar non-additive effects of combining C. papaya with the other plants were found for NH₃ concentrations but not for SCFA concentrations. In conclusion, using mixtures of high-quality plants and high-phenolic plants could be one approach to CH₄ mitigation; however, this awaits in vivo confirmation.

Improving Nutritional Quality of Cocoa Pod (Theobroma cacao) through Chemical and Biological Treatments for Ruminant Feeding: In vitro and In vivo Evaluation

Cocoa pod is among the by-products of cocoa (Theobroma cacao) plantations. The aim of this study was to apply a number of treatments in order to improve nutritional quality of cocoa pod for feeding of ruminants. Cocoa pod was subjected to different treatments, i.e. C (cocoa pod without any treatment or control), CAm (cocoa pod+1.5% urea), CMo (cocoa pod+3% molasses), CRu (cocoa pod+3% rumen content) and CPh (cocoa pod+3% molasses+Phanerochaete chrysosporium inoculum). Analysis of proximate and Van Soest’s fiber fraction were performed on the respective treatments. The pods were then subjected to an in vitro digestibility evaluation by incubation in rumen fluid-buffer medium, employing a randomized complete block design (n = 3 replicates). Further, an in vivo evaluation of the pods (35% inclusion level in total mixed ration) was conducted by feeding to young Holstein steers (average body weight of 145±3.6 kg) with a 5×5 latin square design arrangement (n = 5 replicates). Each experimental period lasted for 30 d; the first 20 d was for feed adaptation, the next 3 d was for sampling of rumen liquid, and the last 7 d was for measurements of digestibility and N balance. Results revealed that lignin content was reduced significantly when cocoa pod was treated with urea, molasses, rumen content or P. chrysosporium (p<0.01) with the following order of effectiveness: CPh>CAm>CRu>CMo. Among all treatments, CAm and CPh treatments significantly improved the in vitro dry matter and organic matter digestibility (p<0.05) of cocoa pod. Average daily gain of steers receiving CAm or CPh treatment was significantly higher than that of control (p<0.01) with an increase of 105% and 92%, respectively. Such higher daily gain was concomitant with higher N retention and proportion of N retention to N intake in CAm and CPh treatments than those of control (p<0.05). It can be concluded from this study that treatment with either urea or P. chrysosporium is effective in improving the nutritive value of cocoa pod.

Assessment of Anti-nutritive Activity of Tannins in Tea By-products Based on In vitro Rumen Fermentation

Nutritive values of green and black tea by-products and anti-nutritive activity of their tannins were evaluated in an in vitro rumen fermentation using various molecular weights of polyethylene glycols (PEG), polyvinyl pyrrolidone (PVP) and polyvinyl polypyrrolidone as tannin-binding agents. Significant improvement in gas production by addition of PEG4000, 6000 and 20000 and PVP was observed only from black tea by-product, but not from green tea by-product. All tannin binding agents increased NH3-N concentration from both green and black tea by-products in the fermentation medium, and the PEG6000 and 20000 showed relatively higher improvement in the NH3-N concentration. The PEG6000 and 20000 also improved in vitro organic matter digestibility and metabolizable energy contents of both tea by-products. It was concluded that high molecular PEG would be suitable to assess the suppressive activity of tannins in tea by-products by in vitro fermentation. Higher responses to gas production and NH3-N concentration from black tea by-product than green tea by-product due to PEG indicate that tannins in black tea by-product could suppress rumen fermentation more strongly than that in green tea by-product.

Use of 3-nitrooxypropanol as feed additive for mitigating enteric methane emissions from ruminants: a meta-analysis

Abstract This study aimed to perform a meta-analysis on the effect of 3-nitrooxypropanol (3-NOP) on enteric methane (CH4) emissions from ruminants. A total of 12 in vivo studies from 10 articles were integrated into a database. Ruminant species included were dairy cows, beef cattle and sheep. Concentration of 3-NOP in diets varied from 0 to 280 mg/kg dry matter intake (DMI). Parameters included were CH4 emissions, rumen fermentation, microbial population, nutrient digestibility and animal performance. Meta-analysis of data was performed by using mixed model methodology in which different studies were treated as random effects whereas 3-NOP addition levels in diets of ruminants were treated as fixed effects. Results showed that increasing level of 3-NOP addition in diets of ruminants decreased enteric CH4 emissions per unit of body weight, CH4/DMI, CH4/milk produced, CH4/digested organic matter or CH4/gross energy intake (p < .05). Production of H2 was higher with increasing level of 3-NOP addition (p < .001). Addition of 3-NOP decreased total VFA concentration (p < .01), and decreased and increased proportions of C2 and C3, respectively (p < .001). Addition of 3-NOP decreased archaea population (p < .01) but it did not change total bacteria and protozoa populations. The substance had minor effect on digestibility of nutrients. Production performance of dairy cows and beef cattle was limitedly influenced by the addition of 3-NOP in the diets, and it had no negative effect on DMI of ruminants. It is concluded that 3-NOP is an effective feed additive to mitigate enteric CH4 emissions without compromising productive performance of ruminants.

Fermentation Characteristics, Tannin Contents and In vitro Ruminal Degradation of Green Tea and Black Tea By-products Ensiled at Different Temperatures

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at 10°C, 20°C, and 30°C. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at 10°C. The GTS stored at 20°C and 30°C showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on NH3-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and NH3-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and NH3-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin’s activity in the rumen.

In vitro gas production kinetics and digestibility of king grass (Pennisetum hybrid) added by organic mineral and natural crude tannin

ABSTRACT This research was conducted to compare kinetics of gas production, methane emission, and in vitro digestibility between organic mineral (OM) and inorganic mineral (IM) in king grass (Pennisetum hybrid), in combination with natural crude tannin from neem (Azadirachta indica, AI) leaves. Treatments were as follows: T0 (king grass as a control), T1 (T0 + 3% IM), T2 (T0 + 3% OM), T3 (T0 + 2% AI), T4 (T0 + 3% IM + 2% AI), T5 (T0 + 3% OM + 2% AI), and T6 (T0 + 40 ppm monensin), and these were arranged on a completely randomized design. Data were analysed using ANOVA and orthogonal contrast test was used for comparing among treatment means. Results showed that either OM or IM supplementation significantly increased (P < .05) gas production. Total gas productions from T0, T3, T5, and T6 were lower than those of T1, T2, and T4. Total VFA, acetate, and propionate were similar in all treatments; however butyrate concentration was higher in T2 and T4 than the others. In vitro organic matter digestibility, protozoa cells number, and ammonia and methane concentrations were not influenced (P > .05) by treatments. In summary, either OM or IM improved fermentability of king grass while their combination with tannin-containing leaves reduced the fermentability without affecting methane production.

Identification and Pathogenicity of Fungal Dieback Disease on Sengon (Paraserianthes falcataria (L.) Nielsen) Seedling and Rice (Oryza sativa)

BACKGROUND AND OBJECTIVE Sengon (Paraserienthes falcataria (L.) Nielsen) is a plant species in forestry plantation while rice (Oryza sativa) is an agricultural crop which potentially used in the agroforestry system. Both species are susceptible to dieback disease. This study aimed to isolate and identify the dieback disease on sengon seedlings to understand the pathogenicity of fungal dieback disease on the seedlings of both sengon and rice and to observe the symptom of dieback disease both macroscopically and microscopically. MATERIALS AND METHODS Pathogenicity test was conducted in a factorial completely randomized design (CRD). The treatments were control, wounded by carborundum, inoculated with pathogen as well as inoculated with pathogen and wounded by carborundum. RESULTS Results revealed that the greatest percentage of dieback disease on sengon and rice was occurred on the treatment of inoculation with wound both100%. While, the greatest percentage of dieback disease intensity of sengon and rice was obtained on the treatment of inoculation with wound by 98.2 and 40.6%, respectively. The PCR result identified that the pathogen was Ceratobasidium ramicola that form imperfect state as Rhizoctonia sp. CONCLUSION This species of fungal pathogen is the major cause of dieback disease on sengon and rice seedlings due to seedlings death.