• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1625-1633
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• 2003

This study was conducted to observe effects of dietary acidogenicity value (AV) on rumen fermentation characteristics and nutrients digestibility. The AV of feedstuffs was based on the dissolution of Ca from $CaCO_3$ powder added at the end of a 24 h in vitro fermentation. Three diets were formulated to be iso-energetic and iso-nitrogenous with different AV. Two experiments were involved in this study. In experiment 1, it appears that pH, $NH_3-N$ concentration and A:P ratio tended to decrease, but gas production, VFA production and DM disappearance tended to increase with increasing dietary AV. In experiment 2, the rumen pH tended to decrease in order of high AV>medium AV>low AV treatment, respectively. There were no significant effects of dietary AV on $NH_3-N$ concentration, enzyme activity and nutrient digestibility. In addition, total VFA and individual VFA concentrations tended to increase with increasing dietary AV without significance. In fact, we hypothesized that different dietary AV would affect rumen fermentation and nutrients digestibility because dietary AV was adjusted with fermentable carbohydrate sources. The present results indicate that differences in dietary AV between treatments were too small to affect rumen fermentation and its effects were minimal.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.603-615
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• 2008

Dietary fiber is an inevitable component in pig diets. In non-ruminants, it may influence many physiological processes in the gastrointestinal tract (GIT) such as transit time as well as nutrient digestion and absorption. Moreover, dietary fiber is also the main substrate of intestinal bacteria. The bacterial community structure is largely susceptible to changes in the fiber content of a pig's diet. Indeed, bacterial composition in the lower GIT will adapt to the supply of high levels of dietary fiber by increased growth of bacteria with cellulolytic, pectinolytic and hemicellulolytic activities such as Ruminococcus spp., Bacteroides spp. and Clostridium spp. Furthermore, there is growing evidence for growth promotion of beneficial bacteria, such as lactobacilli and bifidobacteria, by certain types of dietary fiber in the small intestine of pigs. Studies in rats have shown that both phosphorus (P) and calcium (Ca) play an important role in the fermentative activity and growth of the intestinal microbiota. This can be attributed to the significance of P for the bacterial cell metabolism and to the buffering functions of Ca-phosphate in intestinal digesta. Moreover, under P deficient conditions, ruminal NDF degradation as well as VFA and bacterial ATP production are reduced. Similar studies in pigs are scarce but there is some evidence that dietary fiber may influence the ileal and fecal P digestibility as well as P disappearance in the large intestine, probably due to microbial P requirement for fermentation. On the other hand, fermentation of dietary fiber may improve the availability of minerals such as P and Ca which can be subsequently absorbed and/or utilized by the microbiota of the pig's large intestine.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1610-1616
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• 2006

Influence of different levels of corn steep liquor (CSL) on chemical composition of urea treated wheat straw (UTWS), ruminal characteristics, digestion kinetics, nitrogen (N) utilization, and nutrient digestibility by ruminally-cannulated buffalo bulls was studied in a $4{\times}4$ Latin Square Design. The CSL was used to ensile 5% UTWS at the rate of 0, 3, 6, and 9% on a dry matter (DM) basis. Total N and neutral detergent fibre (NDF) were increased with increasing level of CSL. Increased NDF content was attributable to increased neutral detergent insoluble nitrogen. Four diets were formulated to contain 20% concentrate and 80% UTWS ensiled with 0, (control), 3 (CSL3), 6 (CSL6), and 9% CSL (CSL9). All diets were mixed daily and fed at 1.5% of body weight twice daily. Ruminal NH3 concentration decreased with level of CSL used to ensile UTWS at 3 and 6 h post prandial, however, at 9 h post parandial it was similar across all diets and at 12 h post prandial was higher with diets containing UTWS ensiled with CSL. Concentrations of total ruminal volatile fatty acid and acetate were increased with the CSL level used to ensile UTWS. Increased rate of disappearance and reduction in lag time of DM and NDF was recorded with diets containing UTWS ensiled with CSL. Dry matter and NDF digestibilities were higher with CSL diets than on the control diet. Buffalo bulls retained more N with diets containing UTWS ensiled with CSL. The present results indicated that UTWS could be ensiled with CSL to improve its nutritive value and N utilization by ruminants.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.602-608
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• 2010

An atrazine-degrading bacterium, strain KU001, was obtained from a sugarcane field at the Cane and Sugar Research and Development Center at the Kasetsart University, Kamphaeng Saen Campus, Thailand. Strain KU001 had a rod-to-coccus morphological cycle during growth. Biolog carbon source analysis indicated that the isolated bacterium was Arthrobacter histidinolovorans. Sequence analysis of the PCR product indicated that the 16S rRNA gene in strain KU001 was 99% identical to the same region in Arthrobacter sp. The atrazine degradation pathway in strain KU001 consisted of the catabolic genes trzN, atzB, and atzC. Strain KU001 was able to use atrazine as a sole nitrogen source for growth, and surprisingly, atrazine degradation was not inhibited in cells grown on ammonium, nitrate, or urea, as compared with cells cultivated on growth-limiting nitrogen sources. During the atrazine degradation process, the supplementation of nitrate completely inhibited atrazine degradation activity in strain KU001, whereas ammonium and urea had no effect on atrazine degradation activity. The addition of strain KU001 to sterile or nonsterile soils resulted in the disappearance of atrazine at a rate that was 4- to 5-fold more than that achieved by the indigenous microbial community. The addition of citrate to soils resulted in enhanced atrazine degradation, where 80% of atrazine disappeared within one day following nutrient supplementation.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1593-1598
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• 2003

Nutritional evaluation of some agro-industrial byproducts available in Samoa [dry brewers' grains (DBG), cocoa shell (CS), cocoa dust (CD) and desiccated coconut waste meal (DCWM)] available in Samoa was carried out using both the in vivo and in vitro techniques. In the in vivo study 24 Anglo-nubian goats were offered by-products with other feed ingredients to compound four different diets. The goats were randomly allocated to 4 diets on the basis of liveweight (18.7-0.3kg). The ADF content of the byproducts followed a similar trend to NDF. The byproducts have a high content of organic matter (91.0-95.4%). Gross energy (GE) content was higher in DCWM (25.1 MJ/kg DM), closely followed by CD (23.2 MJ/kg DM). Concentrate intake was significantly different (p<0.05) among the goats. Average daily live weight gains were 105, 92, 88 and 97 g/goat/day for DBG, CS, CD and DCWM, respectively. Daily live weight gains were higher (p<0.05) in the goats that received DBG, while the least gain was obtained in the goats that received CS byproduct diet. DM digestibility was significantly higher (p<0.05) in the goats on DBG diet than in the other goats. The least DM digestibility was obtained in the goats that received CD diet (p>0.05). CP digestibility followed a similar pattern to DM digestibility. The digestibility of NDF and ADF was influenced by the nature of the diets. The digestibility of OM and GE were best (p<0.05) in the goats that received DBG, DCWM and CS byproduct diets than in CD. Significant differences (p<0.05) among the byproducts were recorded for net gas production. Potential gas production (a+b) ranged from 7.064 to 42.17 ml. Organic matter digested (OMD) from gas production value at 24 h was higher in DBG (47.6 g/kg DM) and this was followed by DCWM (42.5 g/kg DM). The least OMD was obtained in CD (17.9 g/kg DM). A significant difference (p<0.05) in DM disappearance after 4, 8, 16, 24, 48 and 72 h was recorded. The potential and effective degradability varied significantly (p<0.05) from 85.95-99.6 g/kg DM and from 39.9-65.8%, respectively. The digestibility of the byproducts in both the in vivo and in in vitro techniques demonstrated that they are potential source of feed ingredients for ruminant livestock in Samoa and possibly in the other small Pacific Island countries. On the basis of their potential degradability the byproducts could be ranked in the following order:DCWM>DBG>CD>CS. In conclusion, the results obtained suggest that all the byproducts can contribute to ruminant livestock diets without adverse effects on feed intake, growth rate and apparent nutrient digestibility coefficients.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.781-790
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• 2011

The effects of seedtime and maturity stage on nutritive value of five maize stover varieties, including conventional maize (Kexiangyu 11, CM), fodder maize (Huqing 1, FM), high oil maize (Gaoyou 115, HOM), sweet maize (Kexiangtianyu 1, SM) and waxy maize (Kexiangluoyu 1, WM), were examined based on chemical composition, in vitro gas production and in situ incubation techniques. Maize stover was sampled at d 17 and d 30 after tasseling, and designated as maturity stage 1 and stage 2, respectively. The average dry matter (DM) organic matter (OM), crude protein (CP) and fiber contents were the greatest for HOM, SM and FM, respectively. CM had the highest in vitro organic matter disappearance (IVOMD) and volatile fatty acid (VFA) concentration. The highest ammonia nitrogen ($NH_3$-N) concentration in the incubation solution, and effective degradability of DM ($ED_{DM}$) and neutral detergent fiber ($ED_{NDF}$) were observed in SM. Advanced maturity stage increased (p<0.05) DM content, $ED_{DM}$ and $ED_{NDF}$, but decreased (p<0.05) OM and CP contents, and decreased (p<0.05) b and a+b values, IVOMD and molar proportion of valerate in the incubation solution for maize stover. Maize sown in summer had greater (p<0.05) OM content, but lower DM, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) content compared with maize sown in spring. Maize sown in summer had greater (p<0.001) IVOMD, $NH_3$-N concentration in the incubation solution and $ED_{NDF}$, but lower (p<0.01) ratio of acetate to propionate compared to maize sown in spring. The interaction effect of variety${\times}$seedtime was observed running through almost all chemical composition, in vitro gas production parameters and in situ DM and NDF degradability. The overall results suggested that SM had the highest nutrient quality, and also indicated the possibility of selecting maize variety and seedtime for the utilization of maize stover in ruminants.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1092-1099
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• 2011

To evaluate the effects of replacing concentrate with urea molasses treated fermented wheat straw (FWS) ensiled with cattle manure (CM) on ruminal characteristics, in situ digestion kinetics and nitrogen (N) metabolism was studied in Nili Ravi cannulated buffalo bulls in a $4{\times}4$ Latin Square Design. Wheat straw treated with urea (4%) and molasses (6%) was ensiled with cattle manure (CM) (70:30) and fermented for 40 days. Four iso-nitrogenous and iso-caloric diets were formulated. In the FWS0, FWS10, FWS20 and FWS30 diets 0, 10, 20 and 30% of the concentrate was replaced with FWS, respectively. Daily intake by bulls was restricted to 1.5% dry matter (DM) of body weight. Ruminal ammonia nitrogen concentration was greater (p<0.05) in bulls fed FWS diet than for those fed FWS0 diet at 3, 6, 9 and 12 h post-parandial. Bulls fed FWS 20 and FWS 30 diets had higher ruminal pH at 3 and 6 h post-parandial than bulls fed FWS10 and FWS0. Ruminal total volatile fatty acid (VFA) concentrations 3 h post-parandial were greater (p<0.05) in bulls fed FWS0 than those fed FWS diets. However ruminal VFA tended to increase at 6, 9 and 12 h post-parandial as the level of FWS increased. In situ ruminal DM and neutral detergent fiber (NDF) degradation, rates of disappearance and extent of digestion were higher (p<0.05) for bulls fed FWS30 diet than those fed FWS0. Ruminal DM and NDF lag time tended to decrease (p<0.05) as FWS concentration in the diet increased. Feed intake, nitrogen intake, N-balance and blood urea-N did not differ (p>0.05) in buffalo bulls fed different diets. Wheat straw treated with urea and molasses and ensiled with CM enhanced the nutritive value of wheat straw and improved nutrient utilization in buffalo bulls when up to 30% of the concentrate was replaced with FWS; no adverse effects on ruminal characteristics and nutrients digestibilities were detected.