• Asian-Australasian Journal of Animal Sciences
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• 제4권4호
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• pp.369-375
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• 1991

A series of in vitro incubation studies with washed rumen bacteria were conducted to determine the influence of incubation time and concentrations of peptides, alanine, ammonia nitrogen and carbohydrate on the rate of peptide disappearance and on bacterial growth. Disappearance rate of tri-alanine (ala3) under various conditions was between 30.6 and $58.2mg\;hr^-$ per gram bacterial dry matter. Ala3 was removed from the incubation medium in an almost linear fashion as incubation time and ala3 concentration was increased. Washed rumen bacteria utilized ala3 faster than di-l-alanine (ala2) at all concentrations. Adding 9mM carbohydrate significantly increased ala3 disappearance, but level of ammonia nitrogen had no influence on ala3 disappearance. The presence of alanine in the medium significantly lowered ala3 utilization by rumen bacteria. Bacterial dry matter and nitrogen growth yield were not influenced by alanine and peptides when incubation medium already contained a sufficient level of ammonia nitrogen. Increased ammonia nitrogen in the presence of ala3 did not stimulate bacterial growth. Carbohydrate significantly increased bacterial dry matter and nitrogen growth as expected. Results indicate that the rate of peptide utilization by rumen bacteria may be altered by type and concentration of peptides, and energy supply, and this may be mediated through changes in numbers and type of bacteria.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1249-1254
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• 2005

The aim of this study was to determine the effect of maturity stage on the nutritive value of wild mustard straw in terms of chemical composition, in situ, in vitro dry matter degradability and calculated ME. The nutritive values of wild mustard, Sinapsis arvensis hays harvested at three stages were evaluated by chemical composition, in vitro gas production and in situ dry matter degradation methods. Gas production or dry matter (DM) degradation were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h and their kinetics were described using the equation p = a+b(1-e$^{-ct}$). Maturity had a significant effect on both the chemical composition and degradability of wild mustard. Neutral detergent fibre (NDF) and acid detergent fibre (ADF) (p<0.001) increased with increasing maturity whereas the crude protein (CP) (p<0.001) decreased. The gas produced after 96 h incubation ranged between 64.7 and 81.5 ml per 0.200 g of dry matter. The gas production (ml) at all incubation times and estimated parameters decreased with increasing maturity of wild mustard. The gas production at all incubation times and estimated parameters (a, b (a+b), metabolizable energy (ME) and organic matter digestibility (OMD)) were negatively correlated with NDF and ADF. The DM disappearance after 96 h incubation ranged between 50.8 and 76.1%. The in situ DM disappearance at all incubation times and estimated parameters decreased with increasing maturity of wild mustard. The in situ dry matter disappearance at all incubation times and some estimated parameters (c, a, b and effective dry matter degradability (EDMD)) were negatively correlated with NDF and ADF but positively correlated with CP. The nutritive value of wild mustard continually changed as it matured. Wild mustard, harvested at the proper stage of maturity offers considerable potential as a high quality forage for ruminants during the winter feeding period. The present study showed that if higher quality forage is an objective, wild mustard should be harvested at the early flowering stage.

• Asian-Australasian Journal of Animal Sciences
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• 제30권4호
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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.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.207-212
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• 2004

Ruminal digestion of dry matter (DM) and neutral detergent fiber (NDF) of processed (ensiled, deepstacked or composted) broiler litter (BL) was determined in situ and in vitro, and compared with rice straw (RS). DM disappearances at 24 and 48 h and digestion of differently processed BL were higher than those of RS. Compared with RS, processed BL was low in NDF disappearance at 72 h incubation, digestion rate ($K_dB$) and digestibility at 0.025 of passage rate; however, deepstacked BL was similar in these NDF characteristics. Processing of BL affected ruminal digestion of nutrients such as DM and NDF adversely. NDF of composted BL, especially, was the most indigestible. This in situ nutritional evaluation indicated that deepstacked BL, the most widely used form of BL, was superior in DM characteristics (fractions, ruminal disappearance and digestibility) and similar in NDF characteristics (ruminal disappearance and digestibility) to RS.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1120-1126
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• 2006

Dry matter (DM) degradation of leaves from Quercus cercis, Quercus libari, Quercus branti, and Quercus coccifera was determined using two different techniques: (i) in vitro gas production and (ii) the nylon bag degradability technique. In vitro gas production in the presence or absence of PEG and in situ DM disappearance were measured at 3, 6, 12, 24, 48, 72 and 96 h. In situ and in vitro DM degradation kinetics were described using the equation y = a+b ($1-e^{-ct}$). At all incubation times leaves from Quercus branti incubated with or without PEG gave significantly higher gas production than the other oak leaves except for 3 and 6 h incubation when leaves from Quercus branti without PEG supplementation only gave higher gas production than Quercus cercis and Quercus coccifera. At all incubation times except at 3, 6 and 12 h the DM disappearance from Quercus branti was significantly higher than the other species. Generally, PEG supplementation considerably increased the gas production at all incubation times and estimated parameters such as gas production rate ($c_{gas}$), gas production (ml) from the quickly soluble fraction ($a_{gas}$), gas production (b) from the insoluble fraction, potential gas production (a+b). However, all oak leaves did not give the same response to the PEG supplementation. Although the increase in gas production at 96 h incubation time was 8.9 ml for Quercus libari the increase was 5.5 ml for Quercus coccifera. It was concluded that except at early incubation times the relationships between the two methodologies seem to be sufficiently strong to predict degradability parameters from gas production parameters obtained in the presence or absence of PEG.

• Asian-Australasian Journal of Animal Sciences
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• 제24권11호
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• pp.1577-1586
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• 2011

This study was carried out to estimate effects of synbiotics containing anaerobic microorganisms and prebiotics on in vitro fermentation characteristics and in situ disappearance rate of fermented total mixed ration (F-TMR). For the in vitro trial, ninety vinyl bags were prepared to analyze temperature, pH, ammonia concentration, microbial growth rate and short chain fatty acid concentration. For the in situ trial, one hundred twenty nylon bags were prepared to analyze dry matter (DM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) disappearance rate. Treatments consisted of a basal diet (US) with prebiotics and probiotics from anaerobic mold (MS), bacteria (BS), yeast (YS) or compound (CS). It was found that temperatures at 14 and 21 days were significantly higher (p<0.05) in the YS and CS than in the others. The pH at 21 days was lower in the CS than in the US. The synbiotic treatments had significantly increased (p<0.05) ammonia concentration at 21 days. The DM disappearance at 72 h was significantly higher (p<0.05) in the MS and CS than in the others. ADF and NDF disappearance rate tended to increase at a rate similar to the DM disappearance rate. Therefore, this study suggests that synbiotics (probiotics with prebiotics) may partially help the quality of fermentation and digestibility of TMR (MS and CS) as fiber disappearance.

• Asian-Australasian Journal of Animal Sciences
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• 제6권4호
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• pp.561-567
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• 1993

Twenty Korean native bulls averaging 181 kg body weight were fed a fixed amount (1.5% of live weight) of concentrate and free choice roughage cubes which had four ratios of rice straw and orchard grass hay; 100:0, 85:15, 70:30 and 55:45 on a weight basis. Five bulls were assigned to each treatment and fed for 98 days in a confinement house. Nutrient digestibility and available energy content of mixed rations (40% concentrate and 60% roughage cubes) was determined in a digestion trial with twelve wethers. In vitro dry matter digestibility (IVDMD) and in situ dry matter disappearance of the roughage cubes were also determined. The ratio of grass hay to rice straw did not influence dry matter intake. Significant improvements in body weight gains and feed/gain ratios were obtained as grass hay levels increased. Average daily gain and feed/gain for each treatment was 0.83, 0.88, 0.98 and 0.99 kg; 7.63m 7.59, 6.83 and 6.41, respectively. Digestibility of the nutrients was improved with increasing levels of grass hay in the cubes. The IVDMD of roughage samples having a ritio of 100:0, 85:15, 70:30 and 55:45 between rice straw and orchard grass hay were 31.0, 37.1, 41.8 and 43.4%, respectively. Grass hay improved the IVDMD of rice straw diets in a linear manner up to 30%. In situ dry matter disappearance rate was also increased as the level of orchard grass hay increased.

• Animal Bioscience
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• 제34권4호
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• pp.584-593
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• 2021

Objective: The objective of this study was to compare fenugreek (FG) with alfalfa (Alf) in ruminal fermentation and methane (CH4) production in vitro. Methods: Whole-plant FG harvested at 11- and 15-wk and Alf harvested at early and mid-bloom maturities, alone or as 50:50 mixture of FG and Alf at the respective maturity, were assessed in a series of 48-h in vitro batch culture incubations. Total fermentation gas and methane gas production, dry matter (DM) disappearance, volatile fatty acids, microbial protein and 16S RNA gene copy numbers of total bacteria and methanogens were determined. Results: Compared to early bloom Alf, FG harvested at 11-wk exhibited higher (p<0.05) in vitro DM and neutral detergent fibre disappearance, but this difference was not observed between the mid-bloom Alf and 15-wk FG. Regardless plant maturity, in vitro ruminal fermentation of FG produced less (p<0.001) CH4 either on DM incubated or on DM disappeared basis than that of Alf during 48-h incubation. In vitro ruminal fermentation of FG yielded similar amount of total volatile fatty acids with higher (p<0.05) propionate percentage as compared to fermentation of Alf irrespective of plant maturity. Microbial protein synthesis was greater (p<0.001) with 11-wk FG than early bloom Alf as substrate and 16S RNA gene copies of total bacteria was higher (p<0.01) with 15-wk FG than mid-bloom Alf as substrate. Compared to mid-bloom Alf, 15-wk FG had lower (p<0.05 to 0.001) amount of 16S RNA methanogen gene copies in the whole culture during 48-h incubation. Conclusion: In comparison to Alf, FG emerges as a high quality forage that can not only improve rumen fermentation in vitro, but can also remarkably mitigate CH4 emissions likely due to being rich in saponins.

• Journal of Animal Science and Technology
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• 제46권3호
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• pp.355-372
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• 2004

식물성유 첨가시 배양시간에 따른 지방산염의 형성 정도와 발효성상 및 NDF 소실율에 미치는 영향을 규명하고자 in vitro 시험을 실시 하였다. 기질은 알팔파 건초로 하고 1) oil 무첨가구, 2) 대두유 10%첨가구 및 3) 옥수수유 10%첨가구로 하였으며, oil 첨가 수준은 기질중량 건물 기준으로 첨가하였다. 발효성상 및 NDF 소실율을 위한 시험에서는 120ml serum bottle을 사용하여 3반복 실시하여 pH, $NH_3-N$, VFA농도 및 건물과 NDF 소실율을 분석하엿다. 지방산 분획을 위한 시험에서는 60ml serum bottle을 사용하요 3반복 실시하여 NEFA, EFA 및 FAS의 형성 정도를 분석하였다. pH는 배양시간이 증가함에 따라 유읭적으로 감소하였고, $NH_3-N$ 농도는 유의하게 증가하였다(P<0.0001). 건물 및 NDF 소실율은 처리구, 배양시간 및 oil간 유의하게 차이를 보여주었다(P<0.05). 총 휘발성 지방산 농도는 배양시간이 증가함에 따라 유의하게 증가하였다(P<0.0001). Acetate는 시험구 모두 배양시간이 증가함에 따라 유의적으로 감소하였고(P<0.0001), 대조구에 비해 oil 첨가구가 유의적으로 낮아졌다(P<0.05). Propionate는 시험구 모두 배양시간이 증가함에 따라 유의적으로 증가하였지만(P<0.0001), 처리구 및 oil간 효과는 없었다. Oil 첨가구에서 A/P비율이 유의하게 낮아졌다(P<0.05). EFA는 배양시간이 증가함에 따라 유의하게 감소하였고(P<0.0001), NEFA는 EFA의 가수분해로 인하여 증가하였다. 배양시간 48시간에서는 NEFA가 양이온과 결합하여 FAS의 형성 비율이 유의적으로 증가하였다(P<0.0001). 특히 $C_{18:0)$의 FAS 형성은 배양시간 48시간에서 대두유 및 옥수수유 첨가구에서 각각 12.53 및 15.17mg/g DM으로 0시간에 비해 각각 27.5 및 32.5배 증가하였다(P<0.0001). 배양시간이 증가할수록 칼슘을 포함한 양이온 함량이 높은 알팔파가 분해되면서 양이온이 용해되어 유리된 지방산과 결합하여 지방산염을 형성하게 된다. 이때 불포화지방산보다는 포화지방산이 양이온과 반응하여 지방산염을 형성하기 쉽다. 또한 $C_{16:0}$ 이상의 장쇄지방산이 주로 지방산염을 형성하였다. 이러한 특성 때문에 배양액내에 유리된 지방산이 염을 형성하기 쉽고 oil 첨가시 발생하는 발효성상 및 NDF소실율에 미치는 부의 영향을 최소화 한 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1606-1613
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• 2015

This study was carried out to investigate the effects of Yerba Mate (YM) supplementation on nutrients' degradation, in vitro dry matter disappearance, gas production and rumen ammonia concentration. Three rumen-fistulated Holstein Friesian cows were used for the in situ incubations and provided rumen liquor for in vitro incubations. The inclusion of YM in a control diet (pasture+pellets) affected some in sacco degradation parameters. YM supplementation decreased the effective degradability and degradation rate of pasture crude protein (CP), and it seems to slow down the degradation of pasture neutral detergent fiber. A significant increase of degradation of pasture acid detergent fiber (ADF) was detected after YM inclusion in the control diet. YM supplementation reduced in vitro gas production of pasture and ammonia concentration of pellets. The addition of YM in ruminant diet could decrease ammonia production and increase protein availability for productive purposes. The moderate presence of tannins in YM could have affected the degradation kinetics of pasture CP and ADF and the ammonia production of pellets.