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排序方式: 共有319条查询结果,搜索用时 15 毫秒
11.
Wyse CA Murphy DM Preston T Sutton DG Morrison DJ Christley RM Love S 《Research in veterinary science》2001,71(1):81-83
The aim of this study was to apply the(13)C-octanoic acid breath test for detection of alterations in the rate of solid-phase gastric emptying, induced by changes in test meal composition, in ponies. After a 14 hour fast the ponies (n = 4) ingested a test meal with 0, 35 or 70 ml soya oil, and labelled with 250 mg(13)C-octanoic acid. Each pony was given each of the three test meals on three separate occasions, in a randomised order. Exhaled breath samples were collected for 12 hours after ingestion of the test meal. Breath samples were analysed by continuous flow isotope ratio mass spectrometry. Three indices of breath(13)C-enrichment were computed, half-dose recovery time (t 1/2), gastric emptying coefficient (GEC) and time to peak breath(13)C-excretion t(max). The(13)C-octanoic acid breath test was a reliable means of assessing the significantly decreased rate of gastric emptying in the pony, associated with addition of soya oil to the test meal. 相似文献
12.
R.L.Preston 《饲料广角》2005,(7):21-22
前言大豆作为蛋白质来源已有五千多年的历史。中国首先提倡种植大豆,本世纪初传入美国。起初,人们主要关心大豆的含油量,提出油以后的大豆粕和大豆皮仅仅是副产品。不久,大豆粕中蛋白质的优异品质被人们所认识。从此,大豆粕成了猪、鸡日粮中补充蛋白质的主要来源。大豆加工时可 相似文献
13.
14.
Preston C Richling E Elss S Appel M Heckel F Hartlieb A Schreier P 《Journal of agricultural and food chemistry》2003,51(27):8027-8031
By use of extracts prepared by liquid-liquid separation of the volatiles from self-prepared juices of pineapple fruits (Ananas comosus) (n = 14) as well as commercial pineapple recovery aromas/water phases (n = 3), on-line capillary gas chromatography-isotope ratio mass spectrometry was employed in the combustion (C) and the pyrolysis (P) modes (HRGC-C/P-IRMS) to determine the delta(13)C(VPDB) and delta(2)H(VSMOW) values of selected pineapple flavor constituents. In addition to methyl 2-methylbutanoate 1, ethyl 2-methylbutanoate 2, methyl hexanoate 3, ethyl hexanoate 4, and 2,5-dimethyl-4-methoxy-3[2H]-furanone 5, each originating from the fruit, the delta(13)C(VPDB) and delta(2)H(VSMOW) data of commercial synthetic 1-5 and "natural" (biotechnologically derived) 1-4 were determined. With delta(13)C(VPDB) data of pineapple volatiles 1-4 varying from -12.8 to -24.4 per thousand, the range expected for CAM metabolism was observed. Compound 5 showed higher depletion from -20.9 to -28.6 per thousand. A similar situation was given for the delta(2)H(VSMOW) values of 3-5 from pineapple ranging from -118 to -191 per thousand, whereas 1 and 2 showed higher depleted values from -184 to -263 per thousand. In nearly all cases, analytical differentiation of 1-5 from pineapple and natural as well as synthetic origin was possible. In general, natural and synthetic 1-5 exhibited delta(13)C(VPDB) data ranging from -11.8 to -32.2 per thousand and -22.7 to -35.9 per thousand, respectively. Their delta(2)H(VSMOW) data were in the range from -242 to -323 per thousand and -49 to -163 per thousand, respectively. 相似文献
15.
Wyse CA McLellan J Dickie AM Sutton DG Preston T Yam PS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(5):609-621
Gastric emptying is the process by which food is delivered to the small intestine at a rate and in a form that optimizes intestinal absorption of nutrients. The rate of gastric emptying is subject to alteration by physiological, pharmacological, and pathological conditions. Gastric emptying of solids is of greater clinical significance because disordered gastric emptying rarely is detectable in the liquid phase. Imaging techniques have the disadvantage of requiring restraint of the animal and access to expensive equipment. Radiographic methods require administration of test meals that are not similar to food. Scintigraphy is the gold standard method for assessment of gastric emptying but requires administration of a radioisotope. Magnetic resonance imaging has not yet been applied for assessment of gastric emptying in small animals. Ultrasonography is a potentially useful, but subjective, method for assessment of gastric emptying in dogs. Gastric tracer methods require insertion of gastric or intestinal cannulae and are rarely applied outside of the research laboratory. The paracetamol absorption test has been applied for assessment of liquid phase gastric emptying in the dog, but requires IV cannulation. The gastric emptying breath test is a noninvasive method for assessment of gastric emptying that has been applied in dogs and cats. This method can be carried out away from the veterinary hospital, but the effects of physiological and pathological abnormalities on the test are not known. Advances in technology will facilitate the development of reliable methods for assessment of gastric emptying in small animals. 相似文献
16.
The objective of this study was to assess post-gastric processing of octanoic acid (OA) by comparing the rate of recovery of 13C in breath with the rate of recovery of 2H in saliva following ingestion of [2H/13C]OA. A test meal with 100mg [13C]OA and 750 mg [2H]OA was ingested on two separate occasions by one dog. Exhaled breath and saliva samples were collected at set time points for 6h following ingestion of the test meal. Two indices were computed, half recovery time (t(1/2)) and the time of peak excretion (t(max)). Recovery of 2H in saliva was quicker than recovery of 13C in breath as determined by the difference in the indices for each isotope; 1.33 and 1.59 h for t(1/2) and t(max), respectively. These findings suggest that the post-gastric processing of OA imposes a delay on the recovery of 13C in breath in the dog, as occurs in man and in the horse. 相似文献
17.
Villarino MA Garcia O Fussell W Preston K Wagner GG 《Preventive veterinary medicine》2003,61(4):333-338
After the civil war and the Hurricane-Mitch disaster, cattlemen in Nicaragua were forced to transport their cattle from lowland areas to higher, dryer areas of the country. These areas are natural ecological niches for the cattle grub Dermatobia hominis (L. Jr.) (Diptera: Cuterebridae). To determine the importance of this infestation, the Agricultural and Livestock-Forestry Ministry selected a central area of Nicaragua to run a pioneer survey program to acquire information about hosts involved, number of cases, treatments applied and general knowledge of 42 farmers about the life cycle of the parasite. The subjects were either farm owners or farm managers. Ninety-five percentage of the farms indicated cases of D. hominis infestation in their animals, with cattle being the most affected host (100% of the affected farms). There was poor understanding of the D. hominis life cycle, vectors and control methods. A misuse of insecticides for the treatment of larval infestation by D. hominis was indicated. 相似文献
18.
The objective of this study was to compare restricted suckling of tropical cows by their own or another cow's calf with artificial rearing of the calves and no suckling. In Exp. 1, cows were mechanically milked twice daily, after which for 15 min they were either suckled by their own calf (Treatment O) or multiple-suckled by other cows' calves (Treatment M) or unsuckled, with the calves reared artificially (Treatment A). Machine milk yield was similar for the three treatments, but in the two suckling treatments the additional milk consumed by the calf increased (P = 0.02) total production (2,682, 2,634, and 2,336 kg/lactation for Treatments O, M, and A, respectively). Machine milk fat concentration was reduced (P = 0.05) by suckling (2.90, 3.07, and 3.20% for Treatments 0, M, and A, respectively), but the milk sampled just before suckling (to represent that taken by the calves) had a high fat concentration (mean 7.9%). Machine milk somatic cell count was also reduced (P = 0.05) by suckling, from 106,000/mL (Treatment A) to 85,000/mL (Treatment M) and 95,000 (Treatment O). Cows suckling their own calf lost more weight and body condition than cows whose calves were reared artificially, with multiple-suckled calves intermediate. Cows suckling their own calf had postpartum interval to first estrus increased (P = 0.01) by 31 d and conception rates to first service of 44% compared to 77% for the other two treatments (P = 0.01). The growth of the suckled calves was compared with that of the artificially reared calves, which were given recommended milk allowances. The artificially reared calves consumed more milk and concentrates, which were available ad libitum to all calves, and gained (P = 0.03) 0.07 kg/d more weight than suckled calves. A second experiment determined that suckling once daily did not reduce reproductive performance compared to artificial rearing. We conclude that suckling cows twice daily increases total milk production but reduces body weight in early lactation. Cows suckling their own calves have reduced reproductive performance compared to those suckling other calves or reared artificially. 相似文献
19.
OBJECTIVE: To evaluate areas of articular contact of the proximal portions of the radius and ulna in normal elbow joints of dogs and the effects of axial load on size and location of these areas. SAMPLE POPULATION: Forelimbs obtained from cadavers of 5 adult mixed-breed dogs. PROCEDURE: After forelimbs were removed, liquid-phase polymethyl methacrylate was applied to articular surfaces of the elbow joint, and limbs were axially loaded. Articular regions void of casting material were stained with water-soluble paint. Relative articular contact areas were determined by computer-assisted image analyses of stained specimens. Repeatability of the technique was evaluated by analyses of casts from bilateral forelimbs of 1 cadaver. Incremental axial loads were applied to left forelimbs from 4 cadavers to determine effects of load on articular contact. RESULTS: Specific areas of articular contact were identified on the radius, the craniolateral aspect of the anconeus, and the medial coronoid process. The medial coronoid and radial contact areas were continuous across the radioulnar articulation. There was no articular contact of the medial aspect of the anconeus with the central trochlear notch. Coefficients of variation of contact areas between repeated tests and between contralateral limbs was < 20%. Significant overall effects of axial load on contact area or location were not identified. CONCLUSIONS: Three distinct contact areas were evident in the elbow joint of dogs. Two ulnar contact areas were detected, suggesting there may be physiologic incongruity of the humeroulnar joint. There was no evidence of surface incongruity between the medial edge of the radial head and the lateral edge of the medial coronoid process. 相似文献
20.
在很多饲料原料中,非降解食入蛋白(UIP)的值都没有检测分析出来,而且也很难对此值作出合理的估测。通常日粮中7%左右的粗蛋白(CP)可以由可降解食入蛋白(DIP)提供;如果日粮中的CP水平超过干物质(DM)的7%,那么超出部分的则为UIP。换句话来说,如果日粮中总共含有13%粗蛋白,那么其中的6%,或者说所有粗蛋白中46%都是以不可降解蛋白(UIP)形式存在的。 相似文献