• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.818-823
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• 2008

The interaction of fibre degrading microbes and methanogens was studied using two forages, lucerne (Medicago sativa) hay and maize (Zea mays) hay, as substrate and 2-bromoethanesulphonic acid (BES) as an additive in an in vitro gas production test. Gas and methane production (ml/g dry matter) were significantly higher (p<0.05) on lucerne as compared to maize hay. Inclusion of BES in the incubation medium significantly suppressed methane emission irrespective of substrate. The population density of total bacteria, fungi, Ruminococcus flavefaciens and Fibrobacter succinogenes was higher, whereas that of methanogens was lower with maize hay as compared to lucerne as substrate. BES suppressed methanogen population by 7 fold on lucerene and by 8.5 fold on maize at 24 h incubation as estimated by real time-PCR. This suppression was accompanied by almost complete (>98% of control) inhibition of methanogenesis. The proportion of acetate decreased, whereas that of propionate increased significantly by inclusion of BES, resulting in narrowing of acetate to propionate ratio. In vitro true digestibility (IVTD) of lucerne was significantly higher as compared to maize but BES inclusion did not affect IVTD.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1705-1711
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• 2014

The objective of this study was to evaluate the effect of ruminally protected amino acids (RPAAs) and ruminally protected fat (RPF) supplementation on ruminal fermentation characteristics (in vitro) and milk yield and milk composition (in vivo). Fourteen mid-lactating Holstein dairy cows (mean weight $653{\pm}62.59kg$) were divided into two groups according to mean milk yield and number of days of postpartum. The cows were then fed a basal diet during adaptation (2 wk) and experimental diets during the treatment period (6 wk). Dietary treatments were i) a basal diet (control) and ii) basal diet containing 50 g of RPAAs (lysine and methionine, 3:1 ratio) and 50 g of RPF. In rumen fermentation trail (in vitro), RPAAs and RPF supplementation had no influence on the ruminal pH, dry matter digestibility, total volatile fatty acid production and ammonia-N concentration. In feeding trial (in vivo), milk yield (p<0.001), 4% fat corrected milk (p<0.05), milk fat (p<0.05), milk protein (p<0.001), and milk urea nitrogen (p<0.05) were greater in cows fed RPAAs and RPF than the corresponding values in the control group. With an index against as 0%, the rates of decrease in milk yield and milk protein were lower in RPAAs and RPF treated diet than those of basal diet group (p<0.05). In conclusion, diet supplemented with RPAAs and RPF can improve milk yield and milk composition without negatively affecting ruminal functions in Holstein dairy cows at mid-lactating.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1598-1603
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• 2018

Objective: The goal of this study was to evaluate kenaf as a roughage source in vitro and its effects on meat quality of Hanwoo (Korean native) cattle. Methods: Three roughage materials, rice straw silage, ryegrass silage, and kenaf silage, were tested in a batch culture and feeding trial. Rumen fermentation parameters, including gas, pH, volatile fatty acid (VFA), and ammonia were analyzed. In the feeding trial, Hanwoo steers ($373.5{\pm}5.1kg$, n = 36, 11 month of age) were divided into three feeding groups (n = 12 each). Animals were fed with each silage and concentrate until the fattening stage. Results: Crude protein, ether extract, and non-structural carbohydrates were greater in kenaf silage. Total gas production was higher in ryegrass silage, followed by kenaf silage and rice straw silage (p<0.05). Total VFA and individual VFA (acetate, propionate, and n-butyrate) were greater in kenaf silage than rice straw silage (p<0.05). In vitro dry matter digestibility showed a similar trend to that of total gas and VFA production; it was higher in ryegrass silage and lower in rice straw (p<0.05). Throughout the feeding trial, the rice straw silage group showed significantly greater average daily gain than did the others (p<0.05). The feed conversion ratio in the group fed kenaf silage was significantly greater than that of others (p<0.05). No significant differences were observed in yield or quality traits, including carcass weight, ribeye area, backfat thickness, and scores for marbling, meat color, and fat color (p>0.05). Conclusion: The results indicated that no negative effects on growth performance and carcass characteristics occurred across treatments. Therefore, kenaf could be substituted for rice straw, which is most widely used as a roughage source in Korea.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.847-853
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• 1999

A Pseudomonas sp. strain that is capable of utilizing dicarboxylic acids as a sole carbon source was isolated from activated sludge by using the enrichment culture technique. This organism accumulated polyhydroxyalkanoates (PHAs) with an unusual pattern of monomer units that depends on the carbon sources used. Polyhydroxybutyrate (PHB) homopolyester was synthesized from glucose or small $C_{-even}$ alkanoic acids, such as butyric acid and hexanoic acid. Accumulation of PHB homopolyester was also observed in the cells grown on $C_{-odd}$ dicarboxylic acids, such as heptanedioic acid and nonanedioic acid as the sole carbon sources. In contrast, a copolyester consisting of 6 mol% 3-hydroxybutyrate (3HB) and 94 mol% 3-hydroxyvalerate (3HV) was produced with a PHA content of as much as 36% of the cellular dry matter. This strain produced PHAs consisting both of the short-chain-length (SCL) and the medium-chain-length (MCL) 3-hydroxyacid units when heptanoic acid to undecanoic acid were fed as the sole carbon sources. Most interestingly, polyester consisting of significant amount of relevant fractions, 3HB, 3HV, and 3-hydroxyheptanoate (3HHp), was accumulated from heptanoic acid. According to solvent fractionation experiments, the polymer produced from heptanoic acid was a blend of poly(3HHp) and of a copolyester of 3HB, 3HV, and 3HHp units. The hexane soluble fractions contained only 3HHp units while the hexane-insoluble fractions contained 3HB and 3HV units with a small amount of 3HHp unit. The copolyester was an elastomer with unusual mechanical properties. The maximum elongation ratio of the copolyester was 460% with an ultimate strength of 10 MPa, which was very different from those of poly(3HB-co-3HV) copolyesters having similar compositions produced from other microorganisms.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.1
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• pp.91-97
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• 1991

Twenty five 75% Holstein Friesian cross bred bullocks fed rice straw (Oryza sativa) of long form, were fed with the following five treatments. 1. Rice straw, untreated (RS) 2. RS + water (1:1), stored for 24 hours (WRS) 3. RS (100 kg) + urea solution (4 kg urea/100 litre water) and dried (USRS) 4. RS (100 kg) + urea solution (as in 3) stored in wet condition for 24 hours (UWRS) 5. RS (100 kg) + urea solution (as in 3) stored in pit for 21 days (UTRS). Potential digestibility of treatments of RS was evaluated by monitoring (in vitro) Simulating Rumen like Fermentation (SRLF). The results indicated that Dry Matter Intake (DMI), digestibility of nutrients, N utilization were of the order UTRS > UWRS > USRS > WRS and RS (p < 0.05 to p < 0.01). SRLF index was high (255.84) for UTRS and least (145.58) for USRS. It was intermediary (199.66) for UWRS. The acetyl content (AC) of UTRS with higher hemicellulose (HCE) digestibility (80.8%) was low compared to UWRS, USRS, RS and WRS. The acetate content was of the order UTRS < UWRS < USRS < WRS and RS thereby indicating that reduction in acetyl content was an index of positive response of urea-treatment of RS. In addition, the ratio of HCE/AC in faeces of UTRS was 0.87 as against the ratios (2.26-2.48) observed in other treatments recording reduction in AC due to urea-treatment. Among the treatments, USRS only supplemented N while UTRS in addition to utilization N, increased the digestibility of structural carbohydrates. Reduction in treatment time from 21 days to 1 day (UWRS) resulted in improvements similar to those of UTRS.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.12
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• pp.1728-1733
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• 2001

An experiment was conducted at the experimental duck farm of Cantho University in the Mekong Delta of Vietnam to evaluate the effects of offering pairwise feeds with different crude protein (CP) levels to Cherry Valley broiler ducks from 28-63 days of age on feed intake and performance. Five diets consisting of mixtures of soya bean meal, fish meal, maize meal and fine rice bran, were formulated to give isocaloric diets with 30, 24, 18, 16 and 12% CP. These were offered separately as pellets to growing ducklings in the following combinations: 30+18, 30+12, 24+16 and 18+12. A diet with 20% CP (CP20) was used as control. All the diets were offered ad libitum. Daily feed intakes (g dry matter, DM) were 161, 168, 150, 101 and 143 g for the 30+18, 30+12, 24+16, 18+12 and CP20 treatments, respectively. CP intakes were 29.6, 27.0, 24.8, 17.1 and 22.9% of total DM intake, and the ratio of methionine+cystine to lysine was 0.76, 0.75, 0.75, 0.76 and 0.75 for the 30+18, 30+12, 24+16, 18+12 and CP20 treatments, respectively. Live weights at 63 days of age were 2,937, 3,054, 2,898, 2,200, and 2,811 g (p<0.001), and daily live weight gains 57.8, 61.7, 57.0, 38.5 and 55.7 g (p<0.001) for the 30+18, 30+12, 24+16, 18+12 and CP20 treatments, respectively. The weights and yields of the carcass, breast and thigh muscles, and heart decreased in the order 30+18, 30+12, 24+16, CP20 and 18+12 (p<0.001). The present study suggests that growing broiler offered a combination of high and low protein feeds pairwise will eat excessive amounts of the high protein feed, thus resulting in protein intakes above requirements.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1228-1234
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• 2000

The reported study was conducted on range managed Malpura ewes that were non-breeding empty, were at an advanced stage of pregnancy, and were in early lactation, under a protocol of free grazing with concentrate supplementation at 1.00, 1.25 and 1.50% of their body weight to assess their plane of nutrition and nutrient intake. The biomass yield of pasture plots was 1689, 1820 and 2912 kg/ha in pregnancy, lactation and empty phases, respectively. In addition to natural shrubs and forbs, Cenchrus ciliaris (36.4%) and dead litter (31.6%) were the major component of pasture vegetation during pregnancy. The dead litter disappeared during the lactation and empty phase with a concomitant increase in distribution of Cenchrus ciliaris to 73.0 and 87.2% respectively. The daily dry matter consumption from supplemental concentrate and free grazing was 70.1, 57.3 and 63.5 g/kg $W^{0.75}/d$ with concentrate to roughage ratio of 40:60, 47:53 and 33:67 in pregnancy, lactation and empty phases respectively. Digestibility of DM and OM were similar in the three phases while CP digestibility was higher (p<0.0l) during lactation than other two phases. Digestibility of NDF, ADF and cellulose were higher (p<0.0l) in empty than pregnancy and lactation, while hemicellulose digestibility was similar in lactation and empty and lower in pregnancy phase. The ewes in ~hases of pregnancy, lactation and empty consumed 7.1, 7.7 and 6.1 g DCP and 197.2, 214.6 and 232.5 kcal DE/kg $W^{0.75}/d$ respectively. It is concluded that ewes maintained on semi-arid Cenchrus dominated pasture with concentrate supplementation during pregnancy, lactation and empty phases consumed 45.2, 45.1 and 35.2 g DCP/Mcal ME respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1604-1609
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• 2008

A series of in vitro and in vivo experiments were conducted to investigate the effects of the mixture of Tween 80 and cellulolytic enzymes (xylanase and cellulase) on total tract nutrient digestibility and rumen cellulolytic bacterial adhesion rates in Holstein steers. Ground timothy hay sprayed with various levels of Tween 80 and cellulolytic enzymes was used as substrates in an in vitro experiment to find out the best combinations for DM degradation. The application level of 2.5% (v/w) Tween 80 and the combination of 5 U xylanase and 2.5 U cellulase per gram of ground timothy hay (DM basis) resulted in the highest in vitro dry matter degradation rate (p<0.05). Feeding the same timothy hay to Holstein steers also improved in vivo nutrient (DM, CP, CF, NDF and ADF) digesibilities compared to non-treated hay (p<0.05). Moreover, Tween 80 and enzyme combination treatment increased total ruminal VFA and concentrations of propionic acid and isovaleric acid with decreased acetate to propionate ratio (p<0.001). However, adhesion rates of Fibrobacter succinogenes and Ruminococcus flavefaciens determined by Real Time PCR were not influenced by the treatment while that of Ruminococcus albus was decreased (p<0.05). The present results indicate that a mixture of Tween 80 and cellulolytic enzymes can improve rumen environment and feed digestibility with variable influence on cellulolytic bacterial adhesion on feed.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.4
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• pp.502-510
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• 2015

The objective of this study was to assess the use of peach pomace in total mixed ration (TMR) silages and clarify the differences in aerobic stability between TMR and TMR silages caused by lactic acid bacteria (LAB). The TMR were prepared using peach pomace, alfalfa hay or Leymus chinensis hay, maize meal, soybean meal, cotton meal, limestone, a vitamin-mineral supplement, and salt in a ratio of 6.0:34.0:44.4:7.0:5.0:2.5:1.0:0.1 on a dry matter (DM) basis. Fermentation quality, microbial composition, and the predominant LAB were examined during ensiling and aerobic deterioration. The results indicated that the TMR silages with peach pomace were well fermented, with low pH and high lactic acid concentrations. The aerobic stability of TMR silages were significantly higher than that of TMR. Compared with TMR silages with alfalfa hay, TMR silage with Leymus chinensis hay was much more prone to deterioration. Although the dominant LAB were not identical in TMR, the same dominant species, Lactobacillus buchneri and Pediococcus acidilactici, were found in both types of TMR silages after 56 d of ensiling, and they may play an important role in the aerobic stability of TMR silages.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.984-992
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• 2009

The objective of this study was to determine the effects of milk supplemented with Sel-Plex on thyroid hormones, rectal temperature, plasma glucose and cholesterol concentrations, and body weight in suckling calves. Ten Holstein suckling male calves of approximately 1 month of age were selected and randomly allocated to one of two groups and fed either unsupplemented milk (control) or milk supplemented with 0.3 mg/kg DM Se from Sel-Plex (treated). The animals received treated milk and free choice starter for two months. Dry matter intake for each individual animal was recorded daily throughout the study. The calves were weighed and blood samples were taken weekly. Plasma concentrations of triiodothyronine ($T_{3}$), thyroxin ($T_{4}$) and $T_{3}$-Uptake were determined using radioimmunoassay kits. Plasma cholesterol and glucose concentrations were determined by enzymatic-colorimetric methods. Rectal temperature was recorded at blood sampling time. During the experiment, ambient temperature and relative humidity were recorded at the time of blood sampling and every four hours. Treatment significantly (p<0.01) affected the concentration of $T_{3}$, free $T_{3}$ index ($FT_{3}I$) and ratio of $T_{3}$:$T_{4}$ in plasma. The plasma concentrations of $T_{3}$ in treated calves were 33% higher than in the control. The plasma concentrations of $T_{4}$ (p<0.05), glucose (p<0.01) and cholesterol (p<0.01) were decreased in the treated group. Calves fed Sel-Plex had higher rectal temperature (p<0.01). Plasma free $T_{4}$ index (FT4I) did not differ significantly between the two groups. An increase in body weight was observed (p<0.09) in the treated group. The results indicated that milk fortified with Sel-Plex could increase tissue conversion of $T_{4}$ to $T_{3}$ and therefore improve thermometabolism in suckling calves.