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121.
M D Soll I H Carmichael S J Gross 《The Onderstepoort journal of veterinary research》1987,54(1):17-20
The efficacy of ivermectin, administered in a sustained release formulation by intraruminal pumps at approximate daily dose rates of 20, 40 and 60 micrograms/kg, was evaluated in 16 cattle against induced infestations of 3 strains of adult Amblyomma hebraeum. Engorged female ticks were mass-measured and incubated, and reproductive data recorded. There was an increase in mortality of male and female ticks compared to that of controls with increasing daily dose of ivermectin, and a decrease in the number of ticks engorging. Ticks fed on ivermectin-treated cattle had a smaller mass when engorged and laid smaller egg masses, both absolutely and as a proportion of engorged mass. Index of reproduction was reduced 100% at 60 micrograms/kg/day, greater than 99% at 40 micrograms/kg/day and 96% at 20 micrograms/kg/day. Differences occurred between the 3 strains of A. hebraeum used in the study, especially with regard to engorged mass and reproductive variables. Practical implications of the application of sustained release ivermectin for the control of A. hebraeum, specifically with reference to heartwater (Cowdria ruminantium), are discussed. 相似文献
122.
The development and adaptation of a fluorescent immunoassay for determining changes in canine haptoglobin levels is described. Levels of canine haptoglobin determined by the fluorescent immunoassay from a group of healthy dog sera (68.0 mg/dl) compared favorably to the haptoglobin levels determined by a spectrophotometric method (74.5 mg/dl). The fluorescent immunoassay offered several advantages over currently used methods for determining levels of canine haptoglobin in serum. 相似文献
123.
D L Harmon K L Gross C R Krehbiel K K Kreikemeier M L Bauer R A Britton 《Journal of animal science》1991,69(10):4117-4127
Twenty calves (7 mo old) were blocked by breed, sex, and weight into five groups of four calves and randomly assigned to either a 90% forage (alfalfa) or a 90% grain (50% sorghum and 50% wheat) diet fed at one (1M) or two (2M) times NEm for 140 d. Samples of ruminal epithelial tissue were collected from the anterior ventral sac, and papillae were cut free by hand and used for in vitro incubations and acyl-CoA synthetase assays. Substrates were acetate (90 mM), propionate (60 mM), butyrate (30 mM), and glucose (20 mM). Net productions of beta-hydroxybutyrate and acetoacetate from acetate were greater (P less than .01) with the 2M feeding; however, 14CO2 production from acetate was greater (P less than .05) with the grain diet. Net production of lactate (P = .09) and pyruvate (P less than .01) from propionate increased with the 2M feeding, whereas net lactate production from glucose decreased (P less than .01). Uptakes of VFA were similar with 1M and 2M feeding and were about 10-fold greater than uptakes of glucose. Production of 14CO2 from propionate was two- to fivefold greater than from acetate, butyrate, or glucose. Oxygen consumption was greater (P less than .01) with 2M feeding and unaffected by substrate. Activities of butyryl-CoA synthetase (nmol.mg of tissue-1.h-1) were greater (P less than .05) for animals consuming the forage diets. Addition of butyrate inhibited acetyl- and propionyl-CoA synthetase activity by 63 and 92%, respectively for all dietary treatments. Overall, metabolism of ruminal epithelial tissue tended to increase with the 2M feeding. Influence of dietary forage content on metabolism and activity of acyl-CoA synthetases was minimal, but the high-forage diet caused slight increases. 相似文献
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125.
The degradation of chlorotoluron, 1-(3-chloro-4-methylphenyl)-3,3-dimethylurea, was investigated in laboratory and field-grown wheat and soil. Thin-layer cochromatography and, partially, derivatization and mass spectroscopy were used to elucidate the structures of the metabolites. Wheat treated with 4-methyl[14C]-phenyl-labeled chlorotoluron rapidly metabolized the herbicide using two independent mechanisms: (I) oxidation of the 4-methylphenyl group to yield 4-hydroxy-methylphenyl and 4-carboxyphenyl derivatives; and (II) N-demethylation. Mechanism (I) clearly predominated over mechanism (II). Young wheat degraded the herbicide mainly to 4-hydroxy-methylphenyl derivatives with only a small fraction being additionally N-monodemethylated. Most of both metabolites was conjugated, most probably, with glucose. In straw and grains of mature field-grown summer wheat treated postemergence with labeled chlorotoluron at a rate corresponding to 2 kg active ingredient/hectare 2.8 ppm and 0.12 ppm radioactivity equivalent to chlorotoluron were found, respectively. About 50% of this terminal radioactivity was nonextractable by organic solvents. No chlorotoluron or its N-demethylated derivatives were present in either plant part. About 40% of the radioactivity in straw consisted of 4-carboxyphenyl derivatives half of which were N-mono- or didemethylated. The rest of the terminal radioactivity was mainly in form of the 4-hydroxymethylphenyl derivative of chlorotoluron. Less than 20% of the soluble metabolites was present as conjugates. In soil mechanism (II) exceeded mechanism (I). At harvest of the wheat the 0.4 ppm radioactivity of the 0- to 30-cm soil layer was composed of 43% chlorotoluron, 36% N-mono- and 3% N-didemethylated chlorotoluron, as well as 13% 4-carboxyphenyl derivatives partly N-demethylated. 相似文献
126.
127.
Saunders DG 《Clinical Techniques in Small Animal Practice》2007,22(4):155-159
Therapeutic exercise is a key component of any rehabilitation program and should be included as part of the concurrent care of any patient whether that patient has two or four legs. Physical therapists have been utilizing therapeutic exercises with great success since the conception of the profession in the beginning of the twentieth century and it has been demonstrated to be fundamental in improving function, performance and disability. Therapeutic exercise can consist of a variety of exercises inclusive of balance, strengthening, range of motion, endurance, and plyometric activities. The goals of therapeutic exercises include the restoration of movement, improvement of function and strength, improvement in gait and balance, and the prevention and the promotion of health, wellness, and fitness. Specific exercises are aimed at restoring strength, power and work, or endurance, or a combination. Therapeutic exercises are also utilized to increase range of motion, decrease pain, improve balance and proprioception, and restore function. 相似文献
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130.
Ursula Gross Rosio Godomar Galindo Hans Schoeneberger 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,32(2):155-164
To ensure the cultivation of the lupine and improve the nutritional state of the Andean population, products have been developed which are enriched with lupine. The high content of bitter alkaloids in the seed of theLupinus mutabilis may be considerably reduced by washing with water (traditional method, ‘Cuzco method’). Drying the grains makes it possible to store them. The lupine with a moisture content of 4 to 8%, can be milled; the flour obtained is slightly yellowish and suitable for panification, where 10 to 40% of the wheat flour may be substituted by lupin. The Protein Efficiency Ratio (PER) of bread was found to be 28% (casein 100%) and was much higher after the enrichment with 10% lupine flour (76%). Lupine based dishes have been well accepted according to a test of acceptability performed with children from 8 to 15 years of age over a three year period. 相似文献