Metha Wanapat

A comparison of alkali treatment methods to improve the nutritive value of straw. I. Digestibility and metabolizability

Abstract A comparative study was conducted to evaluate the effects of alkali treatment of barley straw on digestibility and metabolizability. A total of 16 treatments were tested. The treatments may be grouped according to the chemical and the procedure used, as follows: untreated straw; treatments with urea (or urine); treatments with ammonia (anhydrous or aqueous); “dry” treatments with NaOH; wet treatments with NaOH. Crude protein contents were significantly increased by treatments containing N-sources, especially by urine and urea (6- and 7-fold). The addition of a small amount of soya bean meal (0.5 kg −1 straw) as a urease source did not show any improvement in terms of digestibility and energy utilization. Dip-treated (NaOH) straw contained the highest amount of ash (150 g kg −1 DM). Digestibility of OM was enhanced by 4–7 (urea/urine), 12–15 (anhydrous/aqueous ammonia), 20–23 (wet NaOH) and 12–15 (dry NaOH) percentage units. The corresponding figures for crude fiber digestibility were 15, 20, 30 and 25. Nitrogen balances were higher from treatments containing N-sources. Variations occurred from year to year for the chemical compositions and digestibility obtained among the different data for 5 years. Metabolizable energy of Beckmann-treated, dry-treated (NaOH) and wet (NaOH)-treated straws were 10.52, 9.25 and 9.20 MJ kg −1 DM, respectively. Anhydrous/aqueous NH 3 -treated straw, regardless of method, resulted in a similar ME value (7.64 MJ kg −1 DM). It could be concluded from the digestibility and energy utilization studies that the most efficient treatments, ranked from highest to lowest, were: wet treatment with NaOH; dry treatment with NaOH; anhydrous/aqueous NH 3 treatment; urea/urine treatment.

Potential uses of local feed resources for ruminants

Energy and protein sources are of prime importance for ruminants as they stimulate microorganisms in the rumen and enhance the productive functions of the animals. Cassava roots in the form of dry cassava chips or pellets as energy sources and dried cassava leaves and cassava hay as protein sources have been used successfully in ruminant rations. These uses of cassava could provide year-round feed which results in a high yield and good quality of milk and contribute to a more lucrative dairy and beef cattle enterprise, especially for small-holder dairy farming systems. There are many other available feed resources in the tropics of potential use in ruminant feeding and particularly in the development of food-feed-systems that are not only beneficial for human and animals but also for the environment.

Manipulation of rumen ecology by dietary lemongrass (Cymbopogon citratus Stapf.) powder supplementation

This experiment was conducted to investigate the effect of lemongrass [Cymbopogon citratus (DC.) Stapf.] powder (LGP) on rumen ecology, rumen microorganisms, and digestibility of nutrients. Four ruminally fistulated crossbred (Brahman native) beef cattle were randomly assigned according to a 4 x 4 Latin square design. The dietary treatments were LGP supplementation at 0, 100, 200, and 300 g/d with urea-treated rice straw (5%) fed to allow ad libitum intake. Digestibilities of DM, ether extract, and NDF were significantly different among treatments and were greatest at 100 g/d of supplementation. However, digestibility of CP was decreased with LGP supplementation (P < 0.05), whereas ruminal NH(3)-N and plasma urea N were decreased with incremental additions of LGP (P < 0.05). Ruminal VFA concentrations were similar among supplementation concentrations (P > 0.05). Total viable bacteria, amylolytic bacteria, and cellulolytic bacteria were significantly different among treatments and were greatest at 100 g/d of supplementation (4.7 x 10(9), 1.7 x 10(7), and 2.0 x 10(9) cfu/mL, respectively). Protozoal populations were significantly decreased by LGP supplementation. In addition, efficiency of rumen microbial N synthesis based on OM truly digested in the rumen was enriched by LGP supplementation, especially at 100 g/d (34.2 g of N/kg of OM truly digested in the rumen). Based on this study, it could be concluded that supplementation of LGP at 100 g/d improved digestibilities of nutrients, rumen microbial population, and microbial protein synthesis efficiency, thus improving rumen ecology in beef cattle.

Manipulation of ruminal fermentation and methane production by dietary saponins and tannins from mangosteen peel and soapberry fruit

Four fistulated Holstein Friesian heifers were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement. The main factors were two roughage-to-concentrate ratios (R:C, 70:30 and 30:70) and two supplementation levels of soapberry fruit-mangosteen peel (SM) pellets (0 and 4% tannins-saponins of total diets). Rice straw was used as a roughage source. The diet was fed ad libitum as a total mixed ration. SM pellets contained crude tannins and saponins at 12.1 and 15.7% of DM, respectively. It was found that at R:C 30:70 the DM intake and the digestibility of DM, CP and NDF were increased (p < 0.05), while SM pellet supplementation reduced the DM digestibility (p < 0.05). Ruminal pH was decreased at R:C 30:70. Total VFA and propionate was increased at high concentrate level and after SM pellet supplementation (p < 0.05); simultaneously, the acetate concentration and the acetate-to-propionate ratios were decreased (p < 0.05). Methane production was decreased at R:C 30:70 and additionally when SM pellets were supplemented (p < 0.05). This was in agreement with the percentage of methanogens in total ruminal DNA. Furthermore, the number of fungal zoospores were reduced at a higher concentrate proportion (R:C 30:70) and by SM-pellet supplementation (p < 0.05). Protozoal populations were diminished when SM pellets were supplemented (p < 0.05). In this study, it was shown that the roughage-to-concentrate ratio, as well as the supplementation of SM pellets containing condensed tannins and saponins, caused changes in ruminal microorganisms and their fermentation end-products.

New aspects and strategies for methane mitigation from ruminants

The growing demand for sustainable animal production is compelling researchers to explore the potential approaches to reduce emissions of greenhouse gases from livestock that are mainly produced by enteric fermentation. Some potential solutions, for instance, the use of chemical inhibitors to reduce methanogenesis, are not feasible in routine use due to their toxicity to ruminants, inhibition of efficient rumen function or other transitory effects. Strategies, such as use of plant secondary metabolites and dietary manipulations have emerged to reduce the methane emission, but these still require extensive research before these can be recommended and deployed in the livestock industry sector. Furthermore, immunization vaccines for methanogens and phages are also under investigation for mitigation of enteric methanogenesis. The increasing knowledge of methanogenic diversity in rumen, DNA sequencing technologies and bioinformatics have paved the way for chemogenomic strategies by targeting methane producers. Chemogenomics will help in finding target enzymes and proteins, which will further assist in the screening of natural as well chemical inhibitors. The construction of a methanogenic gene catalogue through these approaches is an attainable objective. This will lead to understand the microbiome function, its relation with the host and feeds, and therefore, will form the basis of practically viable and eco-friendly methane mitigation approaches, while improving the ruminant productivity.

Enriching nutritive value of cassava root by yeast fermentation

Cassava (Manihot esculenta) is extensively cultivated throughout the tropics and subtropics regions due to its ability to grow in diverse soil conditions and minimal management. Experiments were made to study the cassava root fermentation by yeasts in order to enhance the nutritive value of their products (fresh pulp and chips). Both cassava chip (CC) and fresh cassava root pulp (FCR) samples were fermented by Saccharomyces cerevisiae in solid-liquid media fermentation conditions during 132 hours and dried at 30oC. Products were analyzed for proximate composition, mineral composition, essential aminoacids and antinutrient content. There were increases (p < 0.01) in protein (30.4% in CC and 13.5% in fermented cassava root -FCR) and fat contents (5.8% in CC and 3.0% in FCR). S. cerevisiae fermented cassava products had very low hydrocyanic acid (HCN) contents (CC, 0.5 mg kg-1 and FCR, 47.3 mg kg-1). There was a remarkable increase in lysine content in the fermented cassava chip (FCC). The best acceptability and organoleptic attributes (color, texture and aroma) of enriched cassava chip were achieved after 132h of bioprocessing. The results of this study suggest that FCC can be nutritionally improved with S. cerevisiae for animal feeding.

Development of feeding systems and strategies of supplementation to enhance rumen fermentation and ruminant production in the tropics

The availability of local feed resources in various seasons can contribute as essential sources of carbohydrate and protein which significantly impact rumen fermentation and the subsequent productivity of the ruminant. Recent developments, based on enriching protein in cassava chips, have yielded yeast fermented cassava chip protein (YEFECAP) providing up to 47.5% crude protein (CP), which can be used to replace soybean meal. The use of fodder trees has been developed through the process of pelleting; Leucaena leucocephala leaf pellets (LLP), mulberry leaf pellets (MUP) and mangosteen peel and/or garlic pellets, can be used as good sources of protein to supplement ruminant feeding. Apart from producing volatile fatty acids and microbial proteins, greenhouse gases such as methane are also produced in the rumen. Several methods have been used to reduce rumen methane. However, among many approaches, nutritional manipulation using feed formulation and feeding management, especially the use of plant extracts or plants containing secondary compounds (condensed tannins and saponins) and plant oils, has been reported. This approach could help todecrease rumen protozoa and methanogens and thus mitigate the production of methane. At present, more research concerning this burning issue - the role of livestock in global warming - warrants undertaking further research with regard to economic viability and practical feasibility.

A comparison of alkali treatment methods used to improve the nutritive value of straw. II. In sacco and in vitro degradation relative to in vivo digestibility

A comparative study was conducted to evaluate the effects of alkali treatment of barley straw (cultivar ‘Pernilla’) on the in sacco dry matter degradability (ISDMD), in vitro dry matter digestibility (IVDMD) and in vivo dry matter digestibility (IVVDMD). The 15 treatments employed included chemicals such as urea, urine, aqueous ammonia, anhydrous ammonia, and dry and wet processes with sodium hydroxide. The rates of ISDMD were markedly enhanced (P < 0.05) by the wet (NaOH), dry (NaOH), NH3 and urea/urine treatments, in the above order from highest to lowest. The ISDMD and IVDMD were both significantly correlated with IVVDMD (r = 0.95, r = 0.90, respectively). The in vitro and the in sacco methods both underestimated the digestibility of untreated straw, whereas the ISDMD estimates resulting from the wet (NaOH) treatments were higher (P < 0.05) than the IVVDMD estimates. The dry matter digestibility estimates by the three methods are summarized below.

Nutrition and feeding of swamp buffalo: feed resources and rumen approach

Abstract Seasonal feed resources are of prime importance for swamp buffaloes to support the efficient production under the prevailing small-holder farming systems. Manipulations of rumen microorganisms, fermentation and subsequent absorption by the animals are essential. Current research work on locally available feed resources such as urea-treated rice straw, cassava hay etc. revealed significant improvement in rumen ecology with higher cellulolytic bacteria and fungal zoospores and subsequent fermentation endproducts. However, investigation of rumen microorganisms diversity of swamp buffalo and their roles in fermentation using molecular technique especially the use of PCR – DGGE/ Real Time- PCR warrant future research undertakings.

Influence of Rain Tree Pod Meal Supplementation on Rice Straw Based Diets Using In vitro Gas Fermentation Technique

The objective of this study was to determine the roughage to concentrate (R:C) ratio with rain tree pod meal (RPM) supplementation on in vitro fermentation using gas production technique. The experiment design was a 6×4 factorial arrangement in a CRD. Factor A was 6 levels of R:C ratio (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100) and factor B was 4 levels of RPM (0, 4, 8 and 12 mg). It was found that gas kinetic, extent rate (c) was linearly increased (p<0.01) with an increasing level of concentrate while cumulative gas production (96 h) was higher in R:C of 40:60. In addition, interaction of R:C ratio and RPM level affected NH3-N and IVDMD and were highest in R:C of 0:100 with 0, 4 mg of RPM and 40:60 with 8 mg of RPM, respectively. Moreover, interaction of R:C ratio and RPM level significantly increased total volatile fatty acids and propionate concentration whereas lower acetate, acetate to propionate ratios and CH4 production in R:C of 20:80 with 8 mg of RPM. Moreover, the two factors, R:C ratio and RPM level influenced the protozoal population and the percentage of methanogens in the total bacteria population. In addition, the use of real-time PCR found that a high level of concentrate in the diet remarkably decreased three cellulolytic bacteria numbers (F. succinogenes, R. flavefaciens and R. albus). Based on this study, it is suggested that the ratio of R:C at 40:60 and RPM level at 12 mg could improve ruminal fluid fermentation in terms of reducing fermentation losses, thus improving VFA profiles and ruminal ecology.