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Journal of Applied Animal Research |
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Vol.21 No. 2
June 2002 |
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(Abstracted/indexed in
AGRIS Database, Biosis Database, CAB Abstracts,Chemical Abstracts, CURRENT
CONTENTS (AB and ES), Food Science and Technology Abstracts, Indian Science
Abstracts, RESEARCH ALERT, SCISEARCH) |
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TOPIC |
AUTHOR |
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Influence of
tween 80 on the enzyme distribution in rumen liquor and on the growth of
rumen bacteria and fungi |
J.K. Ha, S.S. Lee (Korea), M.
Goto (Japan), Y.H. Moon (Korea)
and K.-J. Cheng (Taiwan) |
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Gastrointestinal tracts of herbivores, particularly the ruminant : anatomy,
physiology and microbial digestion of plants |
Burk A. Dehority (USA) |
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The ruminal
mycoplasmas : A review |
K.N. Joblin and G.E. Naylor
(New Zealand) |
Rumen
microbial responses to antinutritive factors in fodder trees and
shrub legumes |
C.S. McSweeney (Australia), A.
Odenyo (Ethiopia)
and D.O. Krause (Australia) |
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Microbial
eco-system of the gastro-intestinal tract of wild herbivorous animals |
N.P. Sahu and D.N. Kamra
(India) |
Influence of
Tween 80 on the Enzyme Distribution in Rumen Liquor and on the Growth
of Rumen Bacteria and Fungi
J.K. Ha1, S.S. Lee2, M. Goto3,
Y.H. Moon4,
K.-J. Cheng5
1School of Agricultural Biotechnology
Seoul National University
Suweon 441-744, Korea
2Faculty of Animal Science
Gyeong Sang National University
Chinju 660-701, Korea
3Mie University, Tsu, Mie 514, Japan
4Department of Dairy Science, Chinju National
University
Chinju 660-758, Korea
5Institute of BioAgricultural Resources
Academia Sinica, Taipei 115, Taiwan, ROC
(Received November 6, 2001; accepted May 3, 2002)
Abstract
Ha, J.K., Lee, S.S., Goto, M., Moon, Y.H. and Cheng, K.
-J. 2002. Influence of Tween 80 on the enzyme distribution in rumen liquor
and on the growth of rumen bacteria and fungi. J. Appl. Anim. Res., 21:
129-143.
The effect of the surfactant Tween 80 on the enzyme
distribution and growth of pure cultures of rumen anaerobic non-cellulolytic
and cellulolytic bacteria
and monocentric and polycentric fungi was
investigated. When Tween 80 was added to rumen fluid at the level of 0.05
and 0.1 per cent (v/v), the total and specific activities of most of the
cell-free enzymes were significantly (P<0.01) increased, but those of
cell-bound enzymes did not follow a definite trend. The growth rates of
rumen noncellulolytic bacteria (Ruminobacter amylophilus, Megasphaera
elsdenii, Prevotella ruminicola and
Selenomonas ruminantium) were significantly (P<0.01) increased by the
addition of Tween 80 at both the concentrations tested. However, the
growth rate of rumen cellulolytic bacteria (Fibrobacter succinogenes,
Ruminococcus albus, Ruminococcus flavefaciens and Butyrivibrio
fibrisolvens) were generally not affected by Tween 80. In general,
Tween 80 appears to affect gram-negative bacteria more than gram-positive
bacteria; and non-cellulolytic bacteria more than cellulolytic bacteria.
The growth rates of ruminal monocentric fungi (Neocallimastix
patriciarum Piromyces communis) and polycentric fungi (Orpinomyces
joyonii and Anaeromyces mucronatus) were also significantly
(P<0.01) increased by the addition of 0.05 per cent Tween 80. These
results indicate that the addition of 0.05 per cent Tween 80 may greatly
stimulate the release of some enzymes from microbial cells and also
stimulate the growth rates of a range of anaerobic ruminal microorganisms
and thus can be used as a potential feed additive for ruminants.
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Gastrointestinal Tracts of Herbivores, Particularly the Ruminant :
Anatomy, Physiology and Microbial Digestion of Plants
Burk A. Dehority
Department of Animal Sciences
The Ohio Agricultural Research and Development Center
The Ohio State University, Wooster, Ohio 44691 USA
(Received October 11, 2001; accepted April 8, 2002)
Abstract
Dehority, B.A. 2002. Gastrointestinal tracts of
herbivores, particularly the ruminant : anatomy, physiology and microbial
digestion of plants. J. Appl. Anim. Res., 21: 145-160.
The ability of herbivores to utilize forages and plants
as their sole energy source is dependent on microorganisms living at
various sites within their gastrointestinal tract. Essentially two types
of herbivores have evolved, those with a post-gastric (hindgut)
fermentation and those with a pre-gastric (foregut) fermentation. Bacteria
are present in the gastrointestinal tract of all herbivores, and many are
also inhabited by ciliate protozoa and fungi. Ruminants, probably the most
abundant of the herbivores, are foregut fermentors with a four-chambered
stomach (rumen, reticulum, omasum and abomasum). Only the last chamber,
the abomasum, is acidic. The environment within the rumen is anaerobic,
39C, with a pH between 6.0 and 7.0.
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The Ruminal
Mycoplasmas : A Review
K.N. Joblin*, G.E. Naylor
Rumen Biotechnology
Grasslands Research Centre, AgResearch, Private Bag 11008
Palmerston North, New Zealand
(Received December 28, 2001; accepted March 7, 2002)
Abstract
Joblin, K.N. and Naylor, G.E. 2002. The ruminal mycoplasmas
: a review. J. Appl. Anim. Res., 21: 161-179.
Mycoplasmas, originally believed to be very primitive
microbes but since found to have evolved from Gram-positive bacteria, are of
considerable scientific interest because they are the smallest prokaryotes
capable of self replication. Their unusual phenotype and lack of a cell wall
would seem to make mycoplasmas vulnerable to microbial attack in complex
microbial environments, yet they are present at population densities of at
least 107-108 per gram digesta in the rumen microbial
ecosystem and appear to be a normal part of the rumen microflora. The
ruminal mycoplasmas are unusual in that they are the only known obligately
anaerobic mycoplasmas. The five known species have been classified to two
genera within a new family, the Anaeroplasmataceae, within the class
Mollicutes. Whereas, many mycoplasmas from other environments grow
only as parasites, those isolated from the rumen are fermentative and grow
in the absence of a host. There is no evidence that they parasitise other
rumen inhabitants although often they are co-isolated with fungi, protozoa
and methanogens. Their role in the rumen is largely unknown. This review
outlines the current knowledge on ruminal mycoplasmas including their
isolation and culture, phylogeny, metabolism, genetics, diversity and
putative ecological roles.
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Rumen Microbial
Responses to Antinutritive Factors in Fodder Trees and Shrub Legumes
C.S. McSweeney, A. Odenyo*, D.O. Krause
CSIRO Livestock Industries, Long Pocket Laboratories
120 Meiers Rd., Indooroopilly 4068, Australia
*International Livestock Research Institute (ILRI)
P.O. Box 5689, Addis Ababa, Ethiopia
(Received December 13, 2001; accepted March 20, 2002)
Abstract
McSweeney, C.S., Odenyo, A. and Krause, D.O. 2002. Rumen
microbial responses to antinutritive factors in fodder trees and shrub
legumes. J. Appl. Anim. Res., 21: 181-205.
The major limitation to ruminant production in many
tropical regions of Africa, Asia and Australia is poor nutrition. Annual
growth rates of animals are restricted by the low nitrogen and high fibre
content of the native grasses and crop residues that form the basis of the
diets in these regions. Supplementation of tropical roughages with fodder
trees and shrubs (FTS) is a promising method to alleviate nutrient
deficiencies associated with these basal diets. However, FTS often contain
toxins and anti-nutritional factors (ANFs) that limit their use as
feedstuffs. Selection and breeding for cultivars that are low in toxins/ANFs
has not been successful since the presence of these compounds is strongly
associated with survival in many tropical environments. A solution to the
problem may be the rumen microorganisms from adapted domestic and wild
ruminants that have evolved rumen fermentation mechanisms to transform or
detoxify some of these plant secondary compounds. This review examines the
use in ruminant feeding systems of FTS that contain deleterious secondary
compounds; our current understanding of microbial interactions with these
secondary compounds, and advances in the use of rumen biotechnology to
overcome these limitations.
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Microbial
Eco-system of the Gastro-intestinal Tract of Wild Herbivorous Animals
N.P. Sahu,* D.N. Kamra**
Centre of Advanced Studies in Animal Nutrition
Indian Veterinary Research Institute
Izatnagar - 243 122, India
(Received May 7, 2002; accepted May 20 2002)
Abstract
Sahu, N.P. and Kamra, D.N. 2002. Microbial eco-system of the
gastro-intestinal tract of wild herbivorous animals. J. Appl. Anim. Res.,
21: 207-230.
The microbial eco-system of the gastro-intestinal tract
plays a very significant role in bioconversion of lignocellulosic feeds into
volatile fatty acids. Their role becomes more important when the diet given
to the animals is of poor quality e.g. in the wild animals, which have to
survive on the natural vegetation in the forests and in lean season the
availability of nutritious feed is scarce. Thus the animals have to depend
upon the efficiency of the microbial eco-system of the gastro-intestinal
tract for extracting the maximum possible nutrients from such feeds. The
literature available on the eco-system of wild animals is not much, but
these studies conducted in different laboratories have been compiled and
presented in this review. Most of the microbial groups reported in wild
animals are similar to those found in the domestic animals, but there do
exist some exceptions in which new species of protozoa, bacteria and fungi
have been reported. Some of these microbes are host specific. Therefore, the
studies of the microbial eco-system of the gastro-intestinal tract of wild
animals is very important and interesting.
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