Short communicationPostprandial changes in particle associated ruminal bacteria in sheep fed ammoniated rice straw
Introduction
The microorganisms in the rumen comprise the numerically important particle associated microbial population that includes up to 70% of all rumen bacteria (Forsberg and Lam, 1977). Therefore, studies on the mode of their attachment and the subsequent digestion of the plant are essential to better understanding of fiber degradation and its possible improvement.
Over the last decade many experiments have indicated the beneficial aspects of ammonia treatment of straw. Most of the studies on ammonia treatment of straw have concentrated on intake, digestibility and animal performance (Brown et al., 1987) and a few on microbial aspects (Minato et al., 1989). Bae et al. (1997) reported that cuticular damage and loss are more prevalent in ammonia treated than untreated rice straw, then underlying tissues are devoid of silica with extensive colonization of bacteria. There is evidence that ammoniation of rice straw tended to increase the cellulolytic bacterial count, leading to increase in fiber digestion, acetate and butyrate production in the rumen (Cann et al., 1991). However, there is little quantitative information on diurnal variations in the rumen bacteria associated with feed particles in vivo (Craig et al., 1987), especially relating to particle sizes.
In the present experiment, we studied the effect of ammoniated rice straw feeding on postprandial changes in particle attached ruminal bacteria. Moreover, bacterial density on different size of particles were also determined to clarify mode of bacterial colonization relating to the fiber digestion of rice straw by the ruminants.
Section snippets
Experimental design, animals, diets and sample collection
Rice straw was ammoniated by a gaseous method (3 g NH3/100 g DM) under environmental condition (average temperature 17 °C), stored for 4 weeks in a sealed bag, and excess ammonia was removed by opening the bag prior to feeding to the animals.
Three adult ruminally cannulated wethers averaging 68 kg in body weight were fed untreated rice straw (UTS) for 6 weeks followed by ammoniated rice straw (ATS) for 6 weeks twice daily at 08:30 and 20:30 h. The wethers were kept individually in spacious pens with
Results
Chemical analysis of the untreated rice straw indicated 61.1% NDF and 36.3% ADF. The responses due to ammoniation resulted in a decrease to 56.6% NDF and an increase to 37.7% ADF. Ammoniation, however, increased total CP content of rice straw almost three-fold (3.9 versus 10.9%) in the present experiment. DM intake for 2 h restriction was 0.89 and 0.92 kg per day for UTS and ATS, respectively.
Ruminal pH was almost always higher for UTS (7.0–7.6) compared to ATS (6.8–7.4) without a significance.
Discussion
Ammoniation causes a higher CP and a lower NDF in general which is in good agreement with the present results. ATS feeding caused a higher NH3 level (21.7 mg/dl) and lower pH (6.8) without affecting total VFA in the rumen. These all are similar to the preceding results. Accordingly, the prepared ATS is thought to reproduce widely accepted phenomena in ATS feeding. All kinetic parameters of the DM and NDF disappearances in the rumen tended to be higher in ATS (Table 1).
Especially, readily
References (18)
- et al.
Effect of silica on the colonization of rice straw by ruminal bacteria
Anim. Feed Sci. Technol.
(1997) - et al.
Digestion properties of ammoniated rice straw in the rumen and lower tract of sheep
Anim. Feed Sci. Technol.
(1991) - et al.
Quantitation of microorganisms associated with the particulate phase of ruminal ingesta
J. Nutr.
(1987) - et al.
Effects of gaseous ammonia on chemical and structural features of cell walls in spring barley straw
Anim. Feed Sci. Technol.
(1993) - et al.
Methods for dietary fiber, neutral detergent fiber and non-starch polysaccharides in relation to animal nutrition
J. Dairy Sci.
(1991) - Association of Official Analytical Chemists, 1984. Official Methods of Analysis, 14th Edition, AOAC, Washington,...
- et al.
Ammoniation or cane molasses supplementation of low quality forage
J. Anim. Sci.
(1987) - et al.
Use of adenosine 5-triphosphate as an indicator of the microbiota biomass in rumen contents
Appl. Environ. Microbiol.
(1977) - Hamada, T., 1971. Sampling and Analysis for Rumen Contents. In: Experimental Methods of Animal Nutrition. Yokendo,...
Cited by (8)
Rice straw, the role of silica and treatments to improve quality
2006, Animal Feed Science and TechnologyEffect of total mixed ration composition on amino acid profiles of different fractions of ruminal microbes in vitro
2006, Journal of Dairy ScienceEffect of ammonia treatment on physical strength of rice straw, distribution of straw particles and particle-associated bacteria in sheep rumen
2004, Animal Feed Science and TechnologyEffect of different supplement on degradation of dry matter and fiber of untreated and urea treated rice straw in the rumen of sheep
2011, Journal of the Indonesian Tropical Animal AgricultureEffects of ammoniating pressures on structure of stem tissues of rice straw
2009, 2009 1st International Conference on Information Science and Engineering, ICISE 2009