• Asian-Australasian Journal of Animal Sciences
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• v.3 no.1
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• pp.21-25
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• 1990

Fructo-oligosaccharides are found in many plants, such as onion, burdock and wheat. They are not well hydrolyzed by digestive enzymes in animals, but are peculiarly assimilated by Bifidobacterium and some useful bacteria. In our previous experiment (Kobayashi et al., 1987) it was suggested that they were effective in decreasing energy loss in the metabolism of dairy calves. In the present study, the effects of fructo-oligosaccharides on body weight, milk-yield and milk-components (fat, protein and solids-not-fat) were investigated in dairy cows. Lactating cows were fed a standard diet containing fructoligo saccharides at 18.70g, 9.35g and 0.0g (control) per 100kg body weight, day for three weeks. Neither treatments significantly affected any of the parameters examined. The fructo-oligosaccharides were assumed to be hydrolyzed by rumen microorganisms and hardly to affect the bacterium florae in the intestines of the lactating cows.

• Animal Bioscience
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• v.34 no.4
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• pp.621-632
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• 2021

Objective: This study was conducted to investigate the effects of supplementation with rumen-protected γ-aminobutyric acid (GABA) on carcass characteristics and meat quality of Hanwoo steers. Methods: Eighteen Hanwoo steers with an average initial weight of 644.83±12.91 kg were randomly allocated into three different groups. Each group consisted of 6 animals that were treated with different diets formulated based on the animals' body weights. The control (C) group was fed a basal diet consisting of concentrate and rice straw with 74% total digestible nutrients (TDNs) and 12% crude protein (CP). The two other groups were treatment groups; one group was fed a basal diet (74% TDNs and 12% CP) supplemented with rumen-protected GABA at a dose of 150 mg/kg feed, and the other group was fed a basal diet (74% TDNs and 12% CP) supplemented with GABA at a dose of 300 mg/kg feed. Results: The GABA supplementation significantly contributed to better growth performance (p<0.05), especially the weight gain and average daily gain. It also contributed to the lower cooking loss (p<0.05), improvements in essential antioxidant enzymes and stable regulation of antioxidant activities in the longissimus lumborum of Hanwoo steers, as represented by the lower formation of malondialdehyde content within the meat, the inhibition of myoglobin oxidation indicated by the retention of the oxymyoglobin percentage, and the suppression of metmyoglobin percentage during cold storage (p<0.05). Conclusion: Higher doses of GABA may not significantly promote better animal performance and meat quality, suggesting that dietary supplementation with GABA at a dose of 100 ppm is sufficient to improve the meat quality of Hanwoo steers.

• Animal Bioscience
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• v.37 no.2_spc
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• pp.396-403
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• 2024

Objective: Monofluoroacetate (MFA) is a potent toxin that blocks ATP production via the Krebs cycle and causes acute toxicity in ruminants consuming MFA-containing plants. The rumen bacterium, Cloacibacillus porcorum strain MFA1 belongs to the phylum Synergistota and can produce fluoride and acetate from MFA as the end-products of dehalorespiration. The aim of this study was to identify the genomic basis for the metabolism of MFA by this bacterium. Methods: A draft genome sequence for C. porcorum strain MFA1 was assembled and quantitative transcriptomic analysis was performed thus highlighting a candidate operon encoding four proteins that are responsible for the carbon-fluorine bond cleavage. Comparative genome analysis of this operon was undertaken with three other species of closely related Synergistota bacteria. Results: Two of the genes in this operon are related to the substrate-binding components of the glycine reductase protein B (GrdB) complex. Glycine shares a similar structure to MFA suggesting a role for these proteins in binding MFA. The remaining two genes in the operon, an antiporter family protein and an oxidoreductase belonging to the radical S-adenosyl methionine superfamily, are hypothesised to transport and activate the GrdB-like protein respectively. Similar operons were identified in a small number of other Synergistota bacteria including type strains of Cloacibacillus porcorum, C. evryensis, and Pyramidobacter piscolens, suggesting lateral transfer of the operon as these genera belong to separate families. We confirmed that all three species can degrade MFA, however, substrate degradation in P. piscolens was notably reduced compared to Cloacibacillus isolates possibly reflecting the loss of the oxidoreductase and antiporter in the P. piscolens operon. Conclusion: Identification of this unusual anaerobic fluoroacetate metabolism extends the known substrates for dehalorespiration and indicates the potential for substrate plasticity in amino acid-reducing enzymes to include xenobiotics.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.479-485
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• 2017

Objective: The effects of particle size of processed barley grain, enzyme addition and microwave treatment on in vitro dry matter (DM) disappearance (DMD), gas production and fermentation pH were investigated for feedlot cattle. Methods: Rumen fluid from four fistulated feedlot cattle fed a diet of 860 dry-rolled barley grain, 90 maize silage and 50 supplement g/kg DM was used as inoculum in 3 batch culture in vitro studies. In Experiment 1, dry-rolled barley and barley ground through a 1-, 2-, or 4-mm screen were used to obtain four substrates differing in particle size. In Experiment 2, cellulase enzyme (ENZ) from Acremonium cellulolyticus Y-94 was added to dry-rolled and ground barley (2-mm) at 0, 0.1, 0.5, 1, and 2 mg/g, while Experiment 3 examined the interactions between microwaving (0, 30, and 60 s microwaving) and ENZ addition (0, 1, and 2 mg/g) using dry-rolled barley and 2-mm ground barley. Results: In Experiment 1, decreasing particle size increased DMD and gas production, and decreased fermentation pH (p<0.01). The DMD (g/kg DM) of the dry-rolled barley after 24 h incubation was considerably lower (p<0.05) than that of the ground barley (119.1 dry-rolled barley versus 284.8 for 4-mm, 341.7 for 2-mm; and 358.6 for 1-mm). In Experiment 2, addition of ENZ to dry-rolled barley increased DMD (p<0.01) and tended to increase (p = 0.09) gas production and decreased (p<0.01) fermentation pH, but these variables were not affected by ENZ addition to ground barley. In Experiment 3, there were no interactions between microwaving and ENZ addition after microwaving for any of the variables. Microwaving had minimal effects (except decreased fermentation pH), but consistent with Experiment 2, ENZ addition increased (p<0.01) DMD and gas production, and decreased (p<0.05) fermentation pH of dry-rolled barley, but not ground barley. Conclusion: We conclude that cellulase enzymes can be used to increase the rumen disappearance of barley grain when it is coarsely processed as in the case of dry-rolled barley. However, microwaving of barley grain offered no further improvements in ruminal fermentation of barley grain.

• Animal Bioscience
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• v.34 no.5
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• pp.867-879
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• 2021

Objective: Fibronectin 3 (FN3) and immunoglobulin like modules (Ig) are usually collocated beside modular cellulase catalytic domains. However, very few researches have investigated the role of these modules. In a previous study, we have sequenced and analyzed bacterial metagenomic DNA in Vietnamese goats' rumen and found that cellulase-producing bacteria and cellulase families were dominant. In this study, the properties of modular cellulases and the role of a FN3 in unique endoglucanase belonging to glycosyl hydorlase (GH) family 5 were determined. Methods: Based on Pfam analysis, the cellulases sequences containing FN3, Ig modules were extracted from 297 complete open reading frames (ORFs). The alkaline, thermostability, tertiary structure of deduced enzymes were predicted by AcalPred, TBI software, Phyre2 and Swiss models. Then, whole and truncated forms of a selected gene were expressed in Escherichia coli and purified by His-tag affinity column for assessment of FN3 ability to enhance enzyme activity, solubility and conformation. Results: From 297 complete ORFs coding for cellulases, 148 sequences containing FN3, Ig were identified. Mostly FN3 appeared in 90.9% beta-glucosidases belonging to glycosyl hydrolase family 3 (GH3) and situated downstream of catalytic domains. The Ig was found upstream of 100% endoglucanase GH9. Rarely FN3 was seen to be situated downstream of X domain and upstream of catalytic domain endoglucanase GH5. Whole enzyme (called XFN3GH5 based on modular structure) and truncate forms FN3, XFN3, FN3GH5, GH5 were cloned in pET22b (+) and pET22SUMO to be expressed in single and fusion forms with a small ubiquitin-related modifier partner (S). The FN3, SFN3 increased GH5 solubility in FN3GH5, SFN3GH5. The SFN3 partly served for GH5 conformation in SFN3GH5, increased modules interaction and enzyme-soluble substrate affinity to enhance SXFN3GH5, SFN3GH5 activities in mixtures. Both SFN3 and SXFN3 did not anchor enzyme on filter paper but exfoliate and separate cellulose chains on filter paper for enzyme hydrolysis. Conclusion: Based on these findings, the presence of FN3 module in certain cellulases was confirmed and it assisted for enzyme conformation and activity in both soluble and insoluble substrate.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.802-810
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• 2007

Fibrobacter succinogenes, a Gram-negative, anaerobic ruminal bacterium is a major fibre digesting species in the rumen. It intensively degrades plant cell walls by an erosion type of mechanism, burrowing its way through the complex matrix of cellulose and hemicellulose with the release of digestible and undigested cell wall fragments. The enzymes involved in this process include a combination of glucanases, xylanases, arabinofuranosidase(s) and esterases. The genome of the bacterium has been sequenced and this has revealed in excess of 100 putative glycosyl hydrolase, pectate lyase and carbohydrate esterase genes, which is greater than the numbers reported present in other major cellulolytic organisms for which genomes have been sequenced. Modelling of the amino acid sequences of two glycanases, CedA and EGB, by reference to crystallized homologs has enabled prediction of the major features of their tertiary structures. Two dimensional gel electrophoresis in conjunction with mass spectroscopy has permitted the documentation of proteins over expressed in F. succinogenes grown on cellulose, and analysis of the cell surfaces of mutant strains unable to bind to cellulose has enabled the identification of candidate proteins with roles in adhesion to the plant cell wall substrate, the precursor to cellulose biodegradation.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.90-101
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• 2004

Se is essential for a number of enzymes that perform important metabolic functions necessary for good health. However, people in many countries do not appear to consume adequate amounts of Se to support the maximal expression of the selenoproteins and Se retention in the body of animals and humans is dependent on the ingested Se source such as organic and inorganic Se. Therefore, this review was discussed to explore metabolic characterization regarding intestinal absorption, bioavailability and selenoprotein synthesis according to animal species such as monogastrics including human beings and ruminants. Generally, organic Se provided to animals is more effective than inorganic Se in body retention for the animal owing to the difference of manner for intestinal absorption. But, Se absorption in ruminants depending on its chemical form still remained questioned by several microbial actions and feeding regimen in the rumen. And Se absorbed through small intestine is utilized for the synthesis of selenoproteins and/or retained as selenoamino acids in the body. Retained Se in the body may be recycled to synthesize selenoproteins as lacked of dietary Se. In conclusion, desirable forms of Se ingestion in the animal may be useful for Se fortification in animal products as well as well being for humans and animals.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.763-772
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• 2004

The patterns of fungal growth and fiber digestion under the microscope, and tile productions of fibrolytic enzyme were studied in an in vitro culture with Neocallimastix frontalis SA when either filter paper or rice straw was provided as sole energy source. Under the microscopic observation, active zoospores attachment, sporangium development and complex rhizoidal system were founded on the surface and at the edge of filter paper. After 7 days of incubation, a reduced fiber mass, a decreased fiber cohesion and a weakened fiber structure by fungal digestion were clearly observed. Similar fungal development was observed with rice straw, but fungal growth and digestion took place mostly on the damaged and exposed portion of rice straw. Although there were some differences in absolute concentration and pattern, the concentration of both cellulase and xylanase increased with incubation time with the higher activity being obtained with filter paper. Their differences were large especially after 48 and 96hr of incubation(P< 0.05). The filter paper was more good inducer of cellulolytic and xylanolytic enzymes compared with complex substrate, rice straw. These findings suggest that the filter paper is the better energy source for N frontalis than the complex substrate, and structural disintegration by physical process is able to help rumen fungal growth on the lignified roughage although anaerobic rumen fungi have mechanical and enzymatic functions for fiber digestion.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.10
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• pp.1425-1434
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• 2008

The study was conducted to evaluate and compare the effects of feed additives on ruminal fermentation, nutrient digestibility and performance of lambs fed diets containing 60% wet brewers grains (WBG). In Experiment 1, two simultaneous trials were conducted. Fifty intact ($20.2{\pm}0.8kg\;BW$) lambs were used in a feedlot trial and 10 (rumen cannulated; $32{\pm}1kg\;BW$) in a digestion trial. The pH, volatile fatty acids (VFA) and ammonia-N in lambs were also estimated. Lambs were randomly assigned to one of five diets: i) without additives (Con), ii) with 1% bicarbonate (Bic), iii) with 1% bentonite (Ben), iv) with 33 mg/kg monensin (Mon) and v) with 200 mg/kg fibrolityc enzymes (Enz). In Experiment 2, 120 RambouilletPelibuey intact male lambs ($19.5{\pm}1.5kg\;BW$) were used in a feedlot trial and randomly assigned to four diets: i) without additives (control), ii) with 1% Bic, iii) with 33 mg/kg Mon and iv) with 1% Bic and 33 mg/kg Mon. In Experiment 1, lambs fed diets containing Bic or Mon had significantly higher final weight, DMI, ADG than other lambs. However, apparent DM, OM, CP, NDF and ADF digestibilities and ruminal individual VFA content were similar (p>0.05) among treatments. Conversely, treatmentcollection period interaction was significant for ruminal pH and NH3. In Experiment 2, lambs fed diets containing a Bic and Mon combination had significantly higher final weight, DMI and ADG. It is concluded lambs fed Bic or Mon or Bic and Mon combination had better performance characteristics than lambs on Ben or Enz.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1110-1115
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• 2005

To study the effect of feeding lactic acid producing bacteria on the performance of cattle calves, twenty four, day old male crossbred cattle calves (Bos indicus${\times}$Bos taurus), were distributed into two groups of 12 animals each. The animals were fed on calf starter containing wheat bran and green berseem ad libitum and milk as per requirement upto 8 weeks of age. The diet of calves of Group 2 was supplemented with 500 ml culture of Lactobacillus acidophilus-15. Total duration of the experiment was 31 weeks. There was no significant difference in intake and digestibility of dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF) and crude protein (CP) between the groups. The rumen pH, protozoa numbers, concentration of volatile fatty acids (VFA), ammonia nitrogen ($NH_3-N$), trichloroacetic acid precipitable nitrogen (TCA-ppt N) and activity of microbial enzymes (carboxymethylcellulase, xylanase, amylase and protease) were not affected due to probiotic supplementation. Average live weight gain of the calves was improved (about 10%) and feed:gain ratio was reduced (about 5%) in the animals given Lactobacillus culture. The data indicated that crossbred calves could be reared on a diet devoid of cereal grain and addition of Lactobacillus culture in the diet resulted in an added advantage in growth performance of the animals.