• Asian-Australasian Journal of Animal Sciences
• /
• 제14권6호
• /
• pp.885-893
• /
• 2001

This review summarizes some recent research into ways of improving the productivity of ruminal fermentation by increasing protein flow from the rumen and decreasing the breakdown of protein that results from the action of ruminal microorganisms. Proteinases derived from the plant seem to be of importance to the overall process of proteolysis in grazing animals. Thus, altering the expression of proteinases in grasses may be a way of improving their nutritive value for ruminants. Inhibiting rumen microbial activity in ammonia formation remains an important objective: new ways of inhibiting peptide and amino acid breakdown are described. Rumen protozoa cause much of the bacterial protein turnover which occurs in the rumen. The major impact of defaunation on N recycling in the sheep rumen is described. Alternatively, if the efficiency of microbial protein synthesis can be increased by judicious addition of certain individual amino acids, protein flow from ruminal fermentation may be increased. Proline may be a key amino acid for non-cellulolytic bacteria, while phenylalanine is important for cellulolytic species. Inhibiting rumen wall tissue breakdown appears to be an important mechanism by which the antibiotic, flavomycin, improves N retention in ruminants. A role for Fusobacterium necrophorum seems likely, and alternative methods for its regulation are required, since growth-promoting antibiotics will soon be banned in many countries.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권4호
• /
• pp.491-500
• /
• 2010

Three experiments were conducted to investigate the effects of polyurethane coated urea on in vitro ruminal fermentation, ammonia release dynamics and lactating performance of Holstein dairy cows fed a steam-flaked corn-based diet. In Exp. 1, a dual-flow continuous culture was run to investigate the effect of polyurethane coated urea on nutrient digestibility, rumen fermentation parameters and microbial efficiency. Three treatment diets with isonitrogenous contents (13.0% CP) were prepared: i) feedgrade urea (FGU) diet; ii) polyurethane coated urea (PCU) diet; and iii) isolated soy protein (ISP) diet. Each of the diets consisted of 40% steam-flaked corn meal, 58.5% forages and 1.5% different sources of nitrogen. PCU and FGU diets had significantly lower digestibility of NDF and ADF (p<0.01) than the ISP diet. Nitrogen source had no significant effect (p = 0.62) on CP digestibility. The microbial efficiency (expressed as grams of microbial N/kg organic matter truly digested (OMTD)) in vitro of the PCU diet (13.0 g N/kg OMTD) was significantly higher than the FGU diet (11.3 g N/kg OMTD), but comparable with the ISP diet (14.7 g N/kg OMTD). Exp. 2, an in vitro ruminal fermentation experiment, was conducted to determine the ammonia release dynamics during an 8 h ruminal fermentation. Three treatment diets were based on steam-flaked corn diets commonly fed to lactating cows in China, in which FGU, PCU or soybean meal (SBM) was added to provide 10% of total dietary N. In vitro $NH_3-N$ concentrations were lower (p<0.05) for the PCU diet than the FGU diet, but similar to that for the SBM diet at all time points. In Exp. 3, a lactation trial was performed using 24 lactating Holstein cows to compare the lactating performance and blood urea nitrogen (BUN) concentrations when cows were fed PCU, FGU and SBM diets. Cows consuming the PCU diet had approximately 12.8% more (p = 0.02) dietary dry matter intake than those consuming the FGU diet. Cows fed the PCU diet had higher milk protein content (3.16% vs. 2.94%) and lower milk urea nitrogen (MUN) concentration (13.0 mg/dl vs. 14.4 mg/dl) than those fed the FGU diet. Blood urea nitrogen (BUN) concentration was significantly lower for cows fed the PCU (16.7 mg/dl) and SBM (16.4 mg/dl) diets than the FGU (18.7 mg/dl) diet. Cows fed the PCU diet had less surplus ruminal N than those fed the FGU diet and produced a comparable lactation performance to the SBM diet, suggesting that polyurethane coated urea can partially substitute soybean meal in the dairy cow diet without impairing lactation performance.

• 농업과학연구
• /
• 제45권3호
• /
• pp.419-427
• /
• 2018

The present study was conducted to investigate the effect of different levels of Korean corn grain on in vitro ruminal fermentation with total mixed ration (TMR) as a basal feed. Three ruminal cannulated Holstein steers (Body Weight $479{\pm}33.0kg$) were used as rumen fluid donors. Treatments for in vitro fermentation were TMR only (control, 3.0 g), TMR substituted partially with high level (HC, TMR 1.5 and corn 1.5 g), and with low level of Korean corn grain (LC, TMR 2.25 and corn 0.75 g), respectively. To measure in vitro ruminal pH, gas production, ammonia N and volatile fatty acids (VFA), the in vitro fermentation incubation was triplicated at $39^{\circ}C$, 120 rpm for 0, 1, 3, 6, 12, 24 and 48 h, respectively. Mean ruminal pH was significantly lower (p < 0.05) for HC than control. Changes in rumen pH was rather similar between the groups till 6 h after incubation, but the lowest pH for HC (pH 5.10) appeared at 48 h compared with control and LC. Total gas production was tended (p < 0.09) to be higher and ammonia N was significantly lower (p < 0.05) for HC than control and LC. Total VFA was higher (p < 0.05) for HC and LC than control but no differences appeared between HC and LC. Overall, the present data indicate that feeding different levels of Korean domestic corn grain may lead to high and sustainable starch degradation in the rumen.

• Asian-Australasian Journal of Animal Sciences
• /
• 제2권3호
• /
• pp.481-482
• /
• 1989

• Asian-Australasian Journal of Animal Sciences
• /
• 제32권7호
• /
• pp.966-976
• /
• 2019

Objective: The methane mitigating potential of various plant-based polyphenol sources is known, but effects of combinations have rarely been tested. The aim of the present study was to determine whether binary and 3-way combinations of such phenol sources affect ruminal fermentation less, similar or more intensively than separate applications. Methods: The extracts used were from Acacia mearnsii bark (acacia), Vitis vinifera (grape) seed, Camellia sinensis leaves (green tea), Uncaria gambir leaves (gambier), Vaccinium macrocarpon berries (cranberry), Fagopyrum esculentum seed (buckwheat), and Ginkgo biloba leaves (ginkgo). All extracts were tested using the Hohenheim gas test. This was done alone at 5% of dry matter (DM). Acacia was also combined with all other single extracts at 5% of DM each, and with two other phenol sources (all possible combinations) at 2.5%+2.5% of DM. Results: Methane formation was reduced by 7% to 9% by acacia, grape seed and green tea and, in addition, by most extract combinations with acacia. Grape seed and green tea alone and in combination with acacia also reduced methane proportion of total gas to the same degree. The extracts of buckwheat and gingko were poor in phenols and promoted ruminal fermentation. All treatments except green tea alone lowered ammonia concentration by up to 23%, and the binary combinations were more effective as acacia alone. With three extracts, linear effects were found with total gas and methane formation, while with ammonia and other traits linear effects were rare. Conclusion: The study identified methane and ammonia mitigating potential of various phenolic plant extracts and showed a number of additive and some non-linear effects of combinations of extracts. Further studies, especially in live animals, should concentrate on combinations of extracts from grape seed, green tea leaves Land acacia bark and determine the ideal dosages of such combinations for the purpose of methane mitigation.

• Journal of Animal Science and Technology
• /
• 제48권1호
• /
• pp.91-100
• /
• 2006

본 실험은 alcohol 사료 처리에 따른 in vitro 발효 pattern의 변화를 검토하여 alcohol 사료 처리가 반추위내 발효 pattern에 미치는 영향을 규명코자 실시하였다. 시험구 처리는 배합사료를 첨가하는 대조구(control), 배합사료와 1, 3 및 5%의 alcohol 사료(Alcoholic feed; AF)를 첨가하는 처리구를 각각 AF-1구, AF-3구 및 AF-5구로 나누어 실시하였다. 배양 12시간 동안 ammonia 농도는 AF-1, AF-5구에서 대조구에 비해 낮았다(p<0.05). 배양액의 alcohol 농도는 alcohol 첨가 수준이 증가할수록 높았다(p<0.05). 배양 12시간에 TVFA 농도는 AF-1, AF-3 및 AF-5에서 대조구에 비해 현저히 높았다(p<0.05). 배양 8～12시간 사이에 acetate 비율은 대조구에서 빠른 속도로 감소하였으며, AF-1, AF-3 및 AF-5구에서는 일정한 수준을 유지하는 것으로 나타났다. Propionate 비율은 배양 8～12시간 사이에 AF-1, AF-3 및 AF-5에 비해 대조구에서 빠른 속도로 증가하였다(p<0.05). Butyrate 및 valerate 비율은 AF-1, AF-3 및 AF-5에서 대조구에 비해 높았다(p<0.05). Caproate 비율은 배양 8시간에 AF-1구, AF-3구 및 AF-5구에서 각각 0.05, 0.58 및 0.47M%로 나타났으나, 대조구에서는 검출되지 않았다. 본 실험의 결과에서 alcohol 사료의 처리는 in vitro 반추위액의 ammonia, alcohol 및 휘발성지방산 농도와 pH에 긍정적인 영향을 미치는 것으로 판단된다. 또한 본 실험의 결과에서는 5%의 alcohol 첨가 수준이 여타 alcohol 첨가 수준에 비해 반추위 발효에 보다 효과적인 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제21권3호
• /
• pp.392-403
• /
• 2008

Four ruminally fistulated Hanwoo steers were used to determine the effects of level and degradability of dietary protein on ruminal fermentation, blood metabolites and concentration of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). Experiments were conducted in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of treatments. Factors were protein supplements with two ruminal crude protein (CP) degradabilities, corn gluten meal (CGM) that was low in degradability (rumen-degraded protein (RDP), 23.4% CP) or soybean meal (SBM) that was high in degradability (RDP, 62.1% CP), and two feeding levels of CP (12.2 or 15.9% dry matter). Ruminal fermentation rates and plasma metabolite concentrations were determined from the RD collected at 2-h intervals and from the blood taken by jugular puncture, respectively. The SNAN fractions (free amino acid, peptide and soluble protein) in RD and OD collected at 2-h intervals were assessed by ninhydrin assay. Mean ruminal ammonia concentrations were 40.5, 74.8, 103.4 and 127.0 mg/L for low CGM, high CGM, low SBM and high SBM, respectively, with statistically significant differences (p<0.01 for CP level and p<0.001 for CP degradability). Blood urea nitrogen concentrations were increased by high CP level (p<0.001) but unaffected by CP degradability. There was a significant (p<0.05) interaction between level and degradability of CP on blood albumin concentrations. Albumin was decreased to a greater extent by increasing degradability of low CP diets (0.26 g/dl) compared with high CP diets (0.02 g/dl). Concentrations of each SNAN fraction in RD (p<0.01) and OD (p<0.05) for high CP diets were higher than those for low CP diets, except for peptides but concentrations of the sum of peptide and free amino acid in RD and OD were significantly higher (p<0.05) for high CP diets than for low CP diets. Soybean meal diets increased free amino acid and peptide concentrations in both RD (p<0.01) and OD (p<0.05) compared to CGM diets. High level and greater degradability of CP increased (p<0.001) mean concentrations of total SNAN in RD and OD. These results suggest that RDP contents, increased by higher level and degradability of dietary protein, may increase release of free amino acids, peptides and soluble proteins in the rumen and omasum from ruminal degradation and solubilization of dietary proteins. Because SNAN in OD indicates the terminal product of ruminal metabolism, increasing CP level and degradability appears to increase the amount of intestine-available nitrogen in the liquid phase.

• 농업과학연구
• /
• 제29권2호
• /
• pp.35-42
• /
• 2002

본 시험은 목탄 및 활성탄의 첨가가 사료의 반추위내 pH 발효성상 건물 및 영양소 소실율 가스 생산량에 미치는 영향을 조사하기 위하여 in vitro 조건에서 실시되었다. 활성탄과 목탄의 첨가 수준은 0.50% 및 1.0%의 수준이었으며, 사료의 조농비율은 오차드 건초와 농후사료 비율을 2:8로 하였다. 그리고 처리간 유의성은 5% 수준에서 검정하였다. 시험 결과를 요약하면, 위액의 pH는 활성탄의 첨가로 유의하게 높아졌다. 그리고 암모니아태 질소는 활성탄 첨가에 의하여 유의하게 높아졌으며, 목탄첨가구는 무첨가구와 비교할 때 유의한 차이가 인정되지 않았다. 또한 VFA molar ratio에서는 전구간에 유의한 차이가 인정되지 않았으며, C2/C3 비율은 유의한 차이는 아니지만 활성탄구가 다소 낮아지는 경향을 나타내었다. 그러나 목탄 첨가구에서는 대조구와 유의한 차이가 인정되지 않았다. 건물 조단백질 조지방 NDF ADF 및 hemicellulose의 소실율은 활성탄 첨가에 의하여 유의하게 증가되는 경향을 나타냈다. 목탄첨가구에 있어서는 0.5%구보다는 1.0%구가 유의하게 높은 성적을 나타내었다. 그러나 hemicellulose의 소실율은 전구간에 유의한 차이가 없었다. 가스 생산량에 미치는 영향은 활성탄 및 목탄 첨가구가 대조구에 비하여 유의하게 많은 양을 나타내었으며, 활성탄 첨가구와 목탄 첨가구를 비교하면 유의한 차이는 아니지만 활성탄 첨가구가 높은 경향을 나타내었다. 위 결과에서 보듯이 활성탄은 가축의 생산성 향상에 유리한 조건을 제공하는 경향이 있지만, 이것을 좀 더 명확히 밝히기 위해서는 활성탄의 흡착능력 위내의 세균총에 대한 연구 및 많은 생체실험도 병행되어야 할 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권2호
• /
• pp.181-188
• /
• 2006

The objective of this research was to determine the effects of synchronizing the rate of dietary energy and nitrogen release on: ruminal fermentation, microbial protein synthesis, blood urea nitrogen, and nutrient digestibility in beef cattle. Four, two-and-a-half year old Brahman-Thai native crossbred steers were selected for the project. Each steer was fitted with a rumen cannula and proximal duodenal cannula. The steers were then randomly assigned in a $4{\times}4$ Latin square design to receive four dietary treatments. Prior to formulation of the dietary treatments, feed ingredients were analyzed for chemical composition and a nylon bag technique was used to analyze the treatments various ingredients for degradability. The treatments were organized in four levels of a synchrony index (0.39, 0.50, 0.62 and 0.74). The results showed that dry matter digestibility trend to be increased (p<0.06), organic matter and acid detergent fiber digestibility increased linearly (p<0.05), while crude protein and neutral detergent fiber digestibility were not significantly different (p>0.05). Higher concentration and fluctuation of ruminal ammonia and blood urea were observed in the animal that received the lower synchrony index diets. As the levels of the synchrony index increased, the concentrations of ruminal ammonia nitrogen and blood urea nitrogen, at the 4 h post feeding, decreased linearly (p<0.05). Total volatile fatty acid and bacteria populations at the 4 h post feeding increased linearly (p<0.05). Microbial protein synthesis trend to be increase (p<0.08). The results of this research indicate that synchronizing the rate of degradation of dietary energy and nitrogen release improves ruminal fermentation, microbial protein synthesis and feed utilization.

• Asian-Australasian Journal of Animal Sciences
• /
• 제6권3호
• /
• pp.395-400
• /
• 1993

Four sheep per treatment were fed either control or 3% calcium salts of long-chain fatty acids (Ca-LCFA) in a total mixed ration (TMR). Feed and free water intakes were not different, but digestibilities of crude protein and crude fiber were lower (p<0.05) and that of crude fat was higher (p<0.05) for sheep fed Ca-LCFA than for control sheep. Dry matter digestibility, ruminal pH and microbial protein yield were not different between treatments and ammonia-N concentration in the rumen was higher for sheep fed Ca-LCFA than for control sheep. A 60-day milk production trial was conducted with thirty lactation Holstein cows. Fifteen cows per treatment were fed TMR containing either control or 3% Ca-LCFA ad libitum. Feed intake was not different between treatments, but milk yield was significantly higher (p<0.05) for cows fed Ca-LCFA than for control cows. Milk fat percentage was slightly higher and milk protein was lower for cows fed Ca-LCFA than for control cows. Lactose and total solid contents in milk were not different between treatments.