• Asian-Australasian Journal of Animal Sciences
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• 제19권12호
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• pp.1749-1754
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• 2006

Two slaughter experiments were conducted to determine the effects of rumen escape starch, by altering dietary starch concentration and corn particle size, on ${\alpha}$-amylase activity in the pancreas and the small intestinal digesta of lambs. In experiment 1, 18 wether lambs (28.5${\pm}$1.6 kg) were fed low, medium or high starch diets for 35 d and slaughtered. Dietary starch concentrations linearly increased rumen escape starch (p<0.05). Pancreatic ${\alpha}$-amylase activity was lower (p<0.05) in lambs fed the low starch diet. When expressed per gram of digesta, ${\alpha}$-amylase activity was lower in lambs fed the low starch diet. However, expressed as total activity, ${\alpha}$-amylase in the digesta was greater in lambs fed the medium starch diet. In experiment 2, 12 wether lambs (23.5${\pm}$0.3 kg) were fed diets with finely cracked corn, coarsely cracked corn and whole corn. These dietary treatments continued for 35 d before tissue collection. Rumen escape starch increased with increasing corn particle size (p<0.05). ${\alpha}$-amylase activity in the pancreas and the small intestinal digesta was significantly greater (p<0.05) in lambs fed the coarsely cracked corn. These data suggest that increasing rumen escape starch results in a quadratic increase in total ${\alpha}$-amylase activity in the pancreas and the small intestinal digesta. Maximum ${\alpha}$-amylase activity is reached when rumen escape starch is about 100-120 g/d in 25-30 kg lambs.

• Journal of Animal Science and Technology
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• 제45권3호
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• pp.443-454
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• 2003

본 연구는 불포화지방산원으로서 C18:2n-6이 풍부한 전지대두와 C18:3n-3이 풍부한 아마종실을 반추동물사료에 18% 배합하였을 때 반추위내 건물소실율과 불포화지방산 소실율 및 조성을 조사하기 위해 in vitro 배양장치에서 실시하였다. 배양시간은 0, 3, 6, 12, 24, 48, 72시간에 걸쳐 실시하였고, 배양 종료 후 각각의 medium digesta는 동결 건조하여 건물과 각 지방산 함량을 분석하였다. 배양 3시간까지는 전지대두와 아마종실의 건물소실율에 차이가 없었으나, 배양 6시간이후부터는 아마종실이 전지대두보다 유의한 증가를 나타내었다 (p< 0.01). 하지만, 배양 48시간이후부터는 두 처리구간에 유의차가 나타나지 않았다 (p>0.05). 한편 가스생성량은 건물소실율과 비슷한 양상을 나타내어 아마종실이 전지대두보다 발효산물인 가스를 보다 많이 생성하나 두 처리구간에 유의한 차이는 나타나지 않았다(p>0.05). C18:0 함량은 배양시간이 증가함에 따라 전지대두와 아마종실 공히 증가하였고, 전지대두가 아마종실 보다 유의하게 높았다(p<0.05). C18:1 조성은 전지대두가 아마종실구보다 유의하게 증가하였다(p<0.05). C18:2와 C18:3의 digesta내 조성은 반추위내 수소첨가현상으로 배양시간이 증가함에 따라 감소하였다. Digesta내 C18:2 함량은 C18:2가 풍부한 전지대두가 아마종실에 비하여 유의하게 증가하였고(p<0.05), C18:3 함량은 C18:3이 풍부한 아마종실이 전지대두에 비하여 유의하게 증가하였다 (p<0.001). 순수 C18:0 생산량 (%)은 C18:2n-6 함량이 풍부한 전지대두가 배양종료 후 332.24%로 아마종실의 133.16%보다 유의하게 증가하였다 (p<0.05). C18:1 소실율은 전지대두가 아마종실보다 유의하게 낮았고 (p<0.05), 특히 배양 3, 6, 12, 24시간에서 전지대두 처리구가 음 (-)값을 나타내었다. C18:2의 소실율은 배양시간이 증가함에 따라 증가하였고, 배양 72시간에 두 처리구 평균 93.31%로 광범위하게 소실되었으나, 처리구간 유의차는 나타나지 않았다 (p>0.05). C18:3 소실율은 C18:2 소실율과 마찬가지로 배양시간이 증가함에 따라 증가하였으며, 특히 아마종실이 전지대두에 비하여 배양 6시간이후부터 유의하게 증가하였다(p<0.05). C18계 불포화지방산 소실율은 아마종실이 전지대두보다 유의하게 높았다 (p<0.05). 이상의 결과로부터 전지대두와 아마종실은 반추동물의 식품 내 유익한 불포화지방산이 침착하는데 충분한 가치가 있는 불포화지방산원이었고, C18계 불포화지방산은 반추위내에서 광범위하게 수소첨가되었다. 아울러 전지대두는 아마종실보다 complete biohydrogenation이 증가하였고, digesta 내 불포화지방산 함량은 사료 중 불포화지방산 함량과 밀접한 관계가 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제10권6호
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• pp.671-678
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• 1997

The objective was to evaluate method of feeding (free access or intubation), method of slaughter (carbon dioxide gas or barbiturate) and digesta flushing medium (distilled water or physiological saline), in the development of an ileal amino acid digestibility assay for 4 week-old broiler chickens. Three diets were used (commercial (C), semi-synthetic meat-and bone meal (MBM) or wheat (W)). For the coarser C and W diets but not for the MBM diet, feeding method had a significant effect on concentrations of chromium (Cr), nitrogen (N), acid detergent fibre (ADF) and neutral detergent fibre (NDF) in the crop contents at a set time after a meal. There appeared to be a selection of food particles under free-access feeding. For birds receiving the wheat diet there was an effect (p < 0.05) of sampling time after feeding on the concentrations of Cr, N, ADF and NDF/Cr in the crop contents. Flushing ileal digesta with distilled water or saline led to similar apparent ileal N digestibility coefficients. Birds given the MBM diet, and killed by inhalation of $CO_2$, had significantly (p < 0.05) lower apparent ileal N digestibility coefficients (73 versus 80%) than those killed by barbiturate overdose.

• Asian-Australasian Journal of Animal Sciences
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• 제29권5호
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• pp.659-665
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• 2016

The effects of three different feeding systems on beef cattle production performance, rumen fermentation, and rumen digesta particle structure were investigated by using 18 Limousin (steers) with a similar body weight ($575{\pm}10kg$) in a 80-d experiment. The animals were equally and randomly divided into three treatment groups, namely, total mixed ration group (cattle fed TMR), SI1 group (cattle fed concentrate firstly then roughage), and SI2 group (cattle fed roughage firstly then concentrate). The results showed that the average daily gain was significantly higher in cattle receiving TMR than in those receiving SI1 and SI2 (p<0.05). Consumption per kg weight gain of concentrate, silage, and combined net energy (NEmf) were significantly decreased when cattle received TMR, unlike when they received SI1 and SI2 (p<0.05), indicating that the feed efficiency of TMR was the highest. Blood urea nitrogen (BUN) was significantly decreased when cattle received TMR compared with that in cattle receiving SI1 (p<0.05), whereas there was no difference compared with that in cattle receiving SI2. Ammonia nitrogen concentration was significantly lower in cattle receiving TMR than in those receiving SI1 and SI2 (p<0.05). The rumen area of cattle that received TMR was significantly larger than that of cattle receiving SI1 (p<0.05), but there was no difference compared with that of cattle receiving SI2. Although there was no significant difference among the three feeding systems in rumen digesta particle distribution, the TMR group trended to have fewer large- and medium-sized particles and more small-sized particles than those in the SI1 and SI2 groups. In conclusion, cattle with dietary TMR showed increased weight gain and ruminal development and decreased BUN. This indicated that TMR feeding was more conducive toward improving the production performance and rumen fermentation of beef cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.401-409
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• 2004

Two experiments were conducted to evaluate the effects of a complex Lactobacilli preparation on performance, resistance to E. coli infection and gut microbial flora of weaning pigs. In exp. 1, twelve pigs (7.65$\pm$1.10 kg BW), weaned at 28 d, were randomly allotted into 2 groups and placed in individual metabolic cages. During the first 7 d, one group of pigs was provided ad libitum access to water containing $10^5$ colony forming units (CFU) Lactobacilli per ml and the control group was provided tap water. The Lactobacilli preparation included Lactobacillus gasseri, L. reuteri, L. acidophilus and L. fermentum, which were isolated from the gastrointestinal (GI) tract mucosa of weaning pigs. On d 8, 20 ml of $10^8$ CFU/ml E. coli solution (serovars K99, K88 and 987P at the ratio of 1:1:1) was orally administered to each pig. Diarrhea scores and diarrhea incidence were recorded from d 7 to 14. On d 14, pigs were euthanized and digesta and mucosa from the stomach, duodenum, jejunum, ileum, cecum and colon were sampled using aseptic technique to determine microflora by culturing bacteria in selective medium. The results showed that Lactobacilli treatment significantly decreased E. coli and aerobe counts (p<0.01) but increased Lactobacilli and anaerobe counts (p<0.01) in digesta and mucosa of most sections of the GI tract. A 66 and 69.1% decrease in diarrhea index and diarrhea incidence, respectively, was observed in the Lactobacilli treated group. In exp. 2, Thirty-six crossbred Duroc$\times$Landrace$\times$Yorkshire piglets, weaned at 28$\pm$2 days, were selected and randomly allocated into 2 groups. There were 18 piglets in each group, 3 piglets in one pen and 6 replicates in each treatment with 3 pens of barrow and 3 pens of female piglet in each treatment. Piglets had ad libitum access to feed and water. The initial body weight of piglet was 7.65$\pm$1.09 kg. Dietary treatments included a non-medicated basal diet with Lactobacilli ($10^5$ CFU/g diet) or carbadox (60 mg/kg) as control. On d 21, six pigs per group (one pig per pen) were euthanized. Ileal digesta was collected to determine apparent amino acid digestibility. Microflora content was determined similarly to exp.1. The results showed that Lactobacilli treatment significantly improved average daily feed intake (ADFI) of pigs compared to carbadox (p<0.05) during the first 2 wks after weaning and average daily gain (ADG) and ADFI increased significantly (p<0.05) from d 8 to 14. Nitrogen and total phosphorus digestibility also increased (p<0.05). Bacterial counts were similar to exp. 1. The results indicate that the complex Lactobacilli preparation improved performance for 2 wks after weaning, enhanced resistance to E. coli infection, and improved microbial balance in the GI tract.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.113-128
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• 1999

Protozoa can represent as half of the total rumen microbial biomass. Around 10 genera are generally present on the same time in the rumen. Based on nutritional aspects they can be divided in large entodiniomorphs, small entodiniomorphs and isotrichs. Their feeding behaviour and their enzymatic activities differ considerably. Many comparisons between defaunated and refaunated animals were carried out during the last two decades to explain the global role of protozoa at the ruminal or animal levels. It is now generally considered that a presence of an abundant protozoal population in the rumen has a negative effect on the amino acid (AA) supply to ruminants and contribute to generate more methane but, nevertheless, protozoa must not be considered as parasites. They are useful for numerous reasons. They stabilise rumen pH when animal are fed diets rich in available starch and decrease the redox potential of rumen digesta. Because cellulolytic bacteria are very sensitive to these two parameters, protozoa indirectly stimulate the bacterial cellulolytic activity and supply their own activity to the rumen microbial ecosystem. They could also supply some peptides in the rumen medium which can stimulate the growth of the rumen microbiota, but this aspect has never been considered in the past. Their high contribution to ammonia production has bad consequences on the urinary nitrogen excretion but means also that less dietary soluble nitrogen is necessary when protozoa are present. Changes in the molar percentages of VFA and gases from rumen fermentations are not so large that they could alter significantly the use of energy by animals. The answer of animals to elimination of protozoa (defaunation) depends on the balance between energy and protein needs of animals and the supply of nutrients supplied through the diet. Defaunation is useful in case of diets short in protein nitrogen but not limited in energy supply for animals having high needs of proteins.

• Asian-Australasian Journal of Animal Sciences
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• 제7권2호
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• pp.273-277
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• 1994

A $3{\times}3$ latin square design experiment was conducted to study eating and rumination behavior in sheep fed rice straw (RS) supplemented with soybean meal (SBM) and barley at three different levels of crude protein: low (40 g CP/d, LCP), medium (67 g/d, MCP) and high (94 g/d, HCP). In addition, all the supplements were formulated to contain the same amount of total digestible nutrients (TDN; 275 g). Daily time spent eating and eating rate of RS were not affected by any supplementation. However, time spent ruminating in sheep fed HCP diet was markedly shorter (p<0.05) than in those fed LCP and MCP diets. Rumination index (ruminating time/100 g DM intake) was also significantly reduced (p<0.05) by increasing level of protein supplementation. Although no significant differences were observed, the daily number of rumination periods tended to be lower, while daily number of boli regurgitated was considerably higher in sheep fed HCP diet than in those fed LCP and MCP diets. Increasing level of protein supplementation did not affect the number of chews per bolus, bolus time and rate of chewing during rumination. It is suggested that increasing level of protein supplementation was associated with more effective microbial reduction of rumen digesta particle size and consequently reduced the time spent ruminating.