• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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• pp.1201-1207
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• 2007

This study compared the recovery rate of intrajugular-administered allantoin in the urine and saliva between swamp buffaloes and zebu cattle to examine whether it could explain the lower excretion rate of urinary purine derivatives (PD) in the buffaloes. Three male swamp buffalo yearlings, with an average body weight of $349{\pm}40.35$ kg, and three Thai native cattle ($154{\pm}3.26$ kg) of similar age and sex were used in the study. Animals were kept in individual pens and fed at a maintenance energy level with a diet containing 65% monk bean husk (Vigna radiata) as roughage and 35% concentrates. Allantoin solution was infused into the jugular vein in four incremental rates equivalent to 0, 5, 10 and 15 mmol/d and urine was collected daily in acidified form. Daily PD excretion was linearly correlated with intrajugular allantoin infusion in both species. The relationship between daily urinary PD excretion (Y, mmol/d) and intrajugular allantoin infused (X, mmol/d) was $Y=0.75{\pm}0.318X+22.45{\pm}2.98$ ($r^2$ = 0.36, n = 12, MSE = 38.02, CV = 21.9, p<0.01) for swamp buffaloes and $Y=0.96{\pm}0.10X+15.93{\pm}0.92$ ($r^2$ = 0.91, n = 12, MSE = 3.60, CV = 8.27, p<0.01) for zebu cattle. The salivary PD concentration was not correlated with intrajugular allantoin infusion in both species, with values for buffaloes numerically lower than those for cattle. The present study reconfirmed previous studies that buffaloes have a lower plasma PD excretion rate via the renal route and a significant proportion (22%) of the plasma PD loss is via the saliva. However, results of our present and previous studies suggest that differences in purine base (PB) metabolism between buffaloes and zebu cattle occur before the purine compounds reach the plasma pool.

• 대한화학회지
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• 제27권4호
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• pp.239-243
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• 1983

퓨린 港代謝物에는 沆癌活性인 것과 非活性인 것이 있는데, 이들을 EHT 方法으로 계산하여 면밀히 검토해 본 결과, 沆癌活性인 것은 DNA 염기의 당이 결합한 위치에 대응되는 위치인 N(9)에서 electron donating ability를 나타내지만, 非活性인 것은 이와 반대임을 알았고 N(9)와 당에 해당되는 위치 (10)간의 overlap population이 가장 작게 나타났다. 이것은 nuclotide level로 전환되어 沆癌活性을 나타낸다는 실험사실과 일치한다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권6호
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• pp.766-773
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• 2011

The objective of the present study was to examine whether yaks possess any adaptive mechanisms of nitrogen (N) metabolism to survive in the harsh foraging environment of the Qinghai-Tibetan Plateau. A grazing experiment on native alpine meadows was conducted to determine availability of herbage biomass and body weight (BW) change of yaks over the year, followed by two indoor feeding trials to investigate adaptation mechanisms of N metabolism in yaks fed at similar intake level to grazing conditions. Three castrated males of each of three genotypes; yak (Bos grunniens), indigenous cattle (Bos taurus) and their crossbred - cattleyak (Bos taurus male${\times}$Bos grunniens female), were used in the housed trials. Results showed that: i) Monthly herbage biomass production and daily grazing intakes by yaks over the year ranged from 220 to 4,664 kg DM per ha, and 1.90 to 8.50 kg DM, respectively. For about seven months each year, yaks suffer from malnutrition as a result of inadequate pasture conditions; ii) Urinary N excretion and N retention by yaks were significantly affected by feeding level, and yaks had a lower (p<0.05) average daily urinary N excretion (0.39 g/kg $BW^{0.75}$) and a greater (p<0.05) N retention (-0.09 g/kg $BW^{0.75}$) than indigenous cattle (0.47 and -0.16 g/kg $BW^{0.75}$, respectively). Fasting daily urinary N excretion was greater (p<0.05) for indigenous cattle than yaks (353 vs. 248 mg/kg $BW^{0.75}$). Purine derivative N excretion and purine derivative N index (PNI) increased with increasing feeding level, while the value of PNI was greater (p<0.05) for yaks and cattleyak (0.11 and 0.12, respectively) than for indigenous cattle (0.09) during the feeding trials. These results suggest that yaks could rely, in part, on the recycling of N to adapt to the harsh forage environment on the Qinghai-Tibetan Plateau.), were used in the housed trials. Results showed that: i) Monthly herbage biomass production and daily grazing intakes by yaks over the year ranged from 220 to 4,664 kg DM per ha, and 1.90 to 8.50 kg DM, respectively. For about seven months each year, yaks suffer from malnutrition as a result of inadequate pasture conditions; ii) Urinary N excretion and N retention by yaks were significantly affected by feeding level, and yaks had a lower (p<0.05) average daily urinary N excretion (0.39 g/kg $BW^{0.75}$) and a greater (p<0.05) N retention (-0.09 g/kg $BW^{0.75}$) than indigenous cattle (0.47 and -0.16 g/kg $BW^{0.75}$, respectively). Fasting daily urinary N excretion was greater (p<0.05) for indigenous cattle than yaks (353 vs. 248 mg/kg $BW^{0.75}$). Purine derivative N excretion and purine derivative N index (PNI) increased with increasing feeding level, while the value of PNI was greater (p<0.05) for yaks and cattleyak (0.11 and 0.12, respectively) than for indigenous cattle (0.09) during the feeding trials. These results suggest that yaks could rely, in part, on the recycling of N to adapt to the harsh forage environment on the Qinghai-Tibetan Plateau.

• 미생물학회지
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• 제32권1호
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• pp.84-90
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• 1994

Adenosine deaminase (ADA)의 여러 기질과 억제물질의 반응 속도론적 상수가 Aspergillusoryzae의 세포내 효소인 ADA의 활성자리에 어떻게 부착하고 어떤 요인을 필요로 하는지를 알기위해 측적되어졌다. kcat/$K_m$값에 의하면 조사된 기질로 작용하는 화합물 중에 3'-deoxyadenosine이 가장 좋은 기질로 작용하는 것으로 밝혀졌다. 몇 개의 유사체가 억제물질로 조사되었는데 purine riboside가 $3.7{\times}10^{-5}$M의 값 $K_i$값을 가지고 가장 강한 억베물질로 나타났다. Adenine은 기질로도 억제물질로도 작용을 못하므로 adenine의 N-9 위치의 ribose가 효소에 부착하는데 중요하다는 것을 시사하고 있다. 또 ADA는 6-chloropurine riboside(6-CPR)의 dechlorination을 촉매화하여 inosine과 Cl이온을 생성한다. 6-CPR의 ADA에 대한 기질 특이성은 정상 기질인 adenine의 0.86%로 측정되었다. ADA의 경쟁적 억제물질인 purine riboside는 비슷한 $K_i$값을 가지고 dechlorination도 억제하므로 deamination과 dechlorination 반응은 효소의 부착자리를 공유하고 있다고 생각되어진다. SH기에 작용하는 화합물중 수은제인 p-chloromercuribenzoate(PCMB), mersalyl acid, $HgCl_2$는 효소의 deamination 반응을 억제했다. Mersalyl acid에 의해 활성이 억제된 ADA는 thiol reagent인 dithiothreitol이나 2-mercaptoethanol에 의해 활성이 회복되지만 PCMB에 의해 억제된 효소는 회복되지 않았다. 각 수은제들이 억제물질로 작용할 때 $K_i$값과 억제양상이 측정되었는데 모두 경쟁적 방해를 보였다. $K_i$값은 10mM 인산완충용액에서 측정한 것이 100 mM 인산완충용액에서 측정한 것보다 훨씬 낮아 인산기가 기질이 아니어도 효소의 부착에 큰 영향을 미치는 것을 보여주고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.661-672
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• 1998

Two experiments were conducted to examine the effects of a range of concentrations of ruminal fluid ammonia ($NH_3$-N) on forage digestibility, microbial growth efficiency and the mix of microbial species. Urea was either continuously infused directly into the rumen of sheep fed 33.3 glh of oaten chaff (Exp. I) or sprayed onto the oaten chaff (750 g/d) given once daily (Exp. 2). Concentrations of $NH_3$-N increased with incremental addition of urea (p < 0.01). Volatile fatty acids (VFA) concentrations and 24 h in sacco organic matter digestibility in the rumen were higher when supplemental urea was given (p < 0.01). The (C2 + C4) : C3 VFA ratio was lower (p < 0.05) when $NH_3$-N was above 200 mgN/I. The fungal sporangia appearing on oat leaf blades were significantly higher when urea was supplemented, indicating that $NH_3$-N was a growthlimiting nutrient for fungi at levels of $NH_3$-N below 30 mgN/l. The density of protozoa was highest when $NH_3$-N concentrations were adjusted to 30 mgN/I for continuously fed ($4.4{\times}10^5/ml$) and to 168 mgN/1 for once daily feeding ($2.9{\times}10^5/ml$). Thereafter increasing concentrations of $NH_3$-N, were associated with a concomitant decline in protozoal densities. At the concentration of $NH_3$-N above 200 mgN/l, the density of protozoa was similar to the density of protozoa in ruminal fluid of the control sheep ($1.8{\times}10^5/ml$). The efficiency of net microbial protein synthesis in the rumen calculated from purine excretion was 17-47% higher when the level of $NH_3$-N was above 200 mgN/1. The possibilities are that 1) there is less bacterial cell lysis in the rumen because of the concomitant decrease in the protozoal pool and/or 2) microbial growth per se in the rumen is more efficient with increasing $NH_3$-N concentrations.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1273-1273
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• 2001

The efficiency of the luminal fermentation process influences overall efficiency of luminal production, animal health and reproduction. Ruminant production systems have a significant impact on the global environment, as well. Animal wastes contribute to pollution of the environment as ammonia volatilized to the air and nitrate leached to ground water. Microbial protein synthesis in the rumen satisfies a large proportion of the protein requirements of animals. Quantifying the microbial synthesis is possible by using markers for lumen bacteria and protozoa such as nucleic acids, purine bases, some specific amino acids, or by isotopic $^{15}N,^{32}P,\;and\;^{35}S$ labelled feeds. All those methods require cannulated animals, they are time-consuming and some methods are very expensive as well. Many attempts have been made to find an alternative method for indirect measurement of microbial synthesis in intact animals. The present investigations aimed to assess possibilities of NIRS for prediction of purine nitrogen excretion and ruminal microbial nitrogen synthesis by NIR spectra of urine. Urine samples were collected from 12 growing sheep,6 of them male, and 6- female. The sheep were included in feeding experiment. The ration consisted of sorghum silage and protein supplements -70:30 on dry matter basis. The protein supplements were chosen to differ in protein degradability. The urine samples were collected daily in a vessel containing $60m{\ell}$ 10% sulphuric acid to reduce pH below 3 and diluted with tap water to 4 liters. Samples were stored in plastic bottles and frozen at $-20^{\circ}C$ until chemical and NIRS analysis. The urine samples were analyzed for purine derivates - allantoin, uric acid, xantine and hypoxantine content. Microbial nitrogen synthesis in the lumen was calculated according to Chen and Gomes, 1995. Transmittance urine spectra with sample thickness 1mm were obtained by NIR System 6500 spectrophotometer in the spectral range 1100-2500nm. The calibration was performed using ISI software and PLS regression, respectively. The following statistical results of NIRS calibration for prediction of purine derivatives and microbial protein synthesis were obtained.(Table Omitted). The result of estimation of purine nitrogen excretion and microbial protein synthesis by NIR spectra of urine showed accuracy, adequate for rapid evaluation of microbial protein synthesis for a large number of animals and different diets. The results indicate that the advantages of the NIRS technology can be extended into animal physiological studies. The fast and low cost NIRS analyses could be used with no significant loss of accuracy when microbial protein synthesis in the lumen and the microbial protein flow in the duodenum are to be assessed by NIRS.

• Asian-Australasian Journal of Animal Sciences
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• 제20권10호
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• pp.1567-1574
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• 2007

A study was carried out to study the response of total purine derivatives (PD) excretion in urine to determine microbial N (MN) supply at four fixed levels of feed intake (namely 95, 80, 60 and 40% of voluntary intake). The crossbred (CB) calves were allocated according to a $4{\times}4$ Latin Square Design and fed wheat straw and concentrate (1:1). The rate of PD excretion (mmol/d) as a linear function of feed intake was 15.85/kg DMI and 20.12/kg DOMI. Based on the endogenous and PD excretion rates obtained in this study, a relationship between daily urinary PD excretion (Y, mmol) and daily microbial protein supply (X, mmol) was developed for crossbred calves as Y = 0.83X+0.296 kg $W^{0.75}$. The derived microbial N values using this equation differed (p<0.001) among the 4 groups and was the highest in L-95 followed by L-80, L-60 and L-40. The relationship between urinary nitrogen loss (Y, g/d) and DOMI (X, kg/d) was established as: Y = 6.038X+21.753 ($r^2$ = 0.663, p<0.01). When urinary excretion of PD (Y, mmol/d) was plotted against intake of DM and DOM (X, kg/d), the equations obtained were: Y = 7.1711X+8.674 ($r^2$ = 0.889, p<0.01) and Y = 12.434X+7.683 ($r^2$ = 0.896, p<0.01), respectively. The proportional contribution of allantoin and uric acid to total PD remained stable irrespective of level of feed intake. Similarly, urinary excretion of creatinine did not differ (p>0.05) between animals fed at different levels. The MN supply was the highest to animals at intake levels L-95, and decreased linearly with corresponding decrease in feed intake. However, the MN supply when expressed per kg DOMI remained statistically (p>0.05) similar irrespective of level of intake. The results revealed that the excretion of urinary purine derivatives were positively correlated with the level of feed intake as well as rumen microbial supply and thus it could be a good indicator for measuring the microbial protein supply and nutritional status of animals.

• Asian-Australasian Journal of Animal Sciences
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• 제19권6호
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• pp.857-864
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• 2006

The aim of this study was to apply the Cornell net carbohydrate and protein system (CNCPS) in subtropical Taiwan. This was done by means of 3 trials, viz, in situ, lactation and metabolic trials, the latter using the urinary purine derivatives (UPD) to estimate the ruminal microbial yield. Dietary treatments were formulated according to different nutrient requirement systems including, (1) a control NRC78 group on NRC (1978), (2) a NRC88 group on NRC (1988), and (3) a CNCPS group on Cornell Net carbohydrate and protein system model. Results from the lactation trial showed that DM intake (DMI) was higher (p<0.05) in the NRC78 than the other treatment groups. The treatments did not significantly influence milk yield, but milk yield after covariance adjustment for DMI was higher in the CNCPS group (p<0.05). The FCM, milk fat content and yield were greater in both the NRC78 and the NRC88 group over the CNCPS group (p<0.05). The treatments did not significantly influence the DMI adjusted FCM. The solid-non-fat and milk protein contents were higher in the CNCPS group (p<0.05) with or without DMI covariance adjustment. Lactating efficiency was higher in the CNCPS group (p<0.05) compared to the other groups. The significantly lowest milk urea-N (MUN) with better protein utilization efficiency in the CNCPS group (p<0.05) suggested that less N would be excreted into the environment. Cows in the CNCPS group excreted significantly more and the NRC88 group significantly less urinary purine derivatives (UPD) implying that more ruminal microbial protein was synthesized in the CNCPS over the NRC88 group. The CNCPS could become the most useful tool in predicting the trends in milk yield, microbial yield and MUN.

• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.479-482
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• 2005

The nutritional worth of Sarson Saag Waste (SSW), a cannery waste, was assessed in comparison with conventional complete diet as a total mixed ration (TMR), and a conventional green fodder, Avena sativa. Each diet was offered ad libitum, supplemented with mineral mixture and common salt, to 4 male murrah buffaloes. The control TMR was made iso-nitrogenous to SSW. Simultaneously, each diet was offered to 3 rumen fistulated male buffaloes for assessing the biochemical changes in the rumen. The nutrient digestibility of unconventional SSW was comparable to that of conventional green fodder-A. sativa but significantly (p<0.05) higher than that of control TMR. The tri-chloro acetic acid (TCA) precipitable-N in the strained rumen liquor of animals fed SSW was considerably higher than that of animals fed A.sativa. The urinary excretion of total purine derivatives was comparable in animals fed SSW and conventional green fodder but significantly (p<0.05) higher than those fed conventional control TMR. The significantly (p<0.05) lower purine nitrogen index (PNI) in animals fed control TMR resulted in significantly (p<0.05) lower microbial protein synthesis than that in animals fed SSW and conventional green fodder. The N-excretion as per cent of nitrogen intake was significantly (p<0.05) lower in animals fed SSW as compared to either of the conventional feeds tested, resulting in significantly (p<0.05) higher Nretention and apparent biological value. SSW supplemented with mineral mixture could serve as an excellent source of nutrients for ruminants.

• 대한화학회지
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• 제36권5호
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• pp.679-684
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• 1992

$trans-[Pd(en)_2Cl_2](ClO_4)-2$ (en = ethylenediamine)와 purine 염기인 Guanine, Adenine 또는 pyrimidine 염기인 Uracil anion을 반응시켜 새로운 팔라듐(IV) 착물을 얻었다. 착물의 중심금속과 각 리간드의 조성비는 $C{\cdot}H{\cdot}N$ 원소 분석으로써 확인하였으며 리간드의 배위자리 등 착물의 구조는 적외선 흡수 스펙트럼 및 $^1H-NMR,\; ^{13}C-NMR$로써 조사하였다. Guanine 또는 Adenine 착물을 purine계 염기가 N7 자리에 배위되었고 출발물질로부터 하나의 en 리간드가 이탈하고 두 $ClO_4^-$가 배위된 $[Pd(en)L_2(ClO_4)_2](ClO_4)_2{\cdot}(en)$ (L = Guanine, Adenine) 구조이다. Uracil 착물은 en과 $ClO_4^-$의 이동없이 Uracil anion의 N1 자리가 배위된 $[Pd(en)_2(Urac)_2](ClO_4)_2$ (Urac = Uracil anion) 구조의 착물로 추정되었다.