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Locoweed (Astragalus lentiginosus) was fed to ewes from 70 to 100 days of pregnancy. Ewes were killed at 100, 115, 130, and 145 days, and selected tissues were collected from both the dam and the fetus for histologic examination. Neurovisceral cytoplasmic vacuolation and neuroaxonal dystrophy decreased in dam and fetus with time after the feeding of locoweed was discontinued.  相似文献   
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On the basis of worm counts in naturally infected Angora-X goats, albendazole at either 3.8mg/kg repeated after 24 hours or as a single dose at 7.6mg/kg, was >99% effective in removing adult Ostertagia and Trichostrongylus spp. Small numbers of adult Haemonchus contortus, Cooperia sp. and Chabertia ovina were present in control but not treated animals. The single dose of 7.6mg/kg removed > 99% of adult Oesophagostomum venulosum whereas the repeated dose of 3.8mg/kg removed only 96%.  相似文献   
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Land degradation is a major threat to the productivity of agricultural land in Australia, and on the soils used for growing wheat (Triticum aestivum) soil erosion and fertility decline are serious problems. A study financed jointly by NSW Agriculture, Grains Research and Development Corporation (GRDC) and agribusiness looked at the effectiveness of using integrated marketing to increase adoption of dryland lucerne (Medicago sativa) in rotations in northwestern NSW as a means to rehabilitate degraded wheat soils. At the time of the study, average wheat and protein yields were declining. Integrated marketing, with heavy reliance on television advertising, was run during Summer 1992 and Autumn 1993. Approximately 750 wheat growers, located around Moree in NSW comprised the target group. A similar number of comparable farmers from around Dalby in southern Queensland, who were not exposed to the promotional campaign, formed the control group. Farmers were surveyed by mail just before and 18 months after the campaign. While the results were compounded by severe drought during the study time, as well as by other constraints, the data suggest none the less the value of this approach in getting farmers to change their practices. One in six wheat growers in the target area were aware of the free information kit available via the advertised 1800 number or freepost mail coupon; one in twelve obtained the kit. Television was the most influential media in eliciting a response, followed by the Australian Grain Magazine. The results suggested that the campaign did in fact engender the desired change. The study highlights the possible role integrated marketing may play in rural Australia, whether the subject dealt with is agricultural, environmental or other, not because of any novelty value, but because of the technique itself. © 1998 John Wiley & Sons, Ltd.  相似文献   
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Components of the organic matter have been studied in three soils from adjacent sites with different long-term treatments: soil I, prolonged arable cultivation; soil II, 17 years under grass after prolonged arable cultivation; and soil III, old pasture. Contents of total organic C in the top 15cm were 0.9% in soil I. 1.7% in soil II and 4.8% in soil III. The light fraction, comprising partially decomposed materials with a specific gravity < 2.06, represented greater proportions of the organic C in soils II and III (20–23 per cent) than in soil I (8.5 per cent). The light fraction of soil III had a relatively high N content.The proportions of the soil organic C released, by hydrolysis, as neutral sugars, uronic acids, amino sugars, amino acids and phenolic acids were generally similar in the three soils, although uronic acids and phenolic acids constituted somewhat greater proportions in soils II and III than in I.The light fractions contained greater proportions of neutral sugars and phenolic acids, and smaller proportions of amino sugars and amino acids than the whole soils.  相似文献   
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Three groups of 5 pigs each were fed a high selenium (Se) diet by mixing either Astragalus praelongus (31.6 ppm Se in feed), A bisulcatus (31.7 ppm Se in feed), or sodium selenate (26.6 ppm Se in feed) with commercial hog feed. Ten control pigs were fed only commercial hog chow containing trace selenium (0.44 ppm Se). Pigs were fed for 9 weeks and necropsied when they had ataxia or paralysis. Blood was collected for hematologic and serum biochemical determinations, and samples of various tissues were collected and fixed in neutral-buffered 10% formalin for histologic evaluation or frozen for determination of selenium concentration. All forms of selenium induced clinical signs of weight and hair loss, with cracked hooves and inflamed coronary bands developing in all Na2SeO4-fed pigs and 1 A praelongus-fed pig, but not in A bisulcatus-fed pigs. Serum calcium, phosphorus, and albumin concentrations were unchanged or significantly decreased from prefeeding values in groups fed selenium. Serum aspartate transaminase (AST) activities in Astragalus species-fed groups, and amylase activities and PCV in all groups of pigs fed selenium, were increased. Serum alkaline phosphatase and creatine kinase activities were significantly increased in the A praelongus-fed pigs and significantly decreased in Na2SeO4-fed pigs. Terminal tissue and body fluid selenium concentrations were determined in all groups of pigs fed selenium and compared with values in control pigs. Urine and bile concentrations were increased by the greatest factor (40 to 100x), with tissue concentrations of selenium increased by a lesser factor (6 to 17x).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Antibiotic impregnated polymethylmethacrylate beads were surgically implanted into the mandible of an adult Bennett's wallaby (Macropus rufogriseus rufogriseus) suffering from chronic mandibular osteomyelitis that had proven refractory to systemic antibiotic treatment. Although a discrete inflammatory mass remained, clinical signs of inappetance and a discharging sinus were alleviated following implantation of the beads. This procedure resulted in a more satisfactory outcome than other methods of treatment used previously for this condition and avoided the problems associated with regular handling and prolonged medication.  相似文献   
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The use of chloramphenicol in the horse is now prohibited as horses are classified as food-producing animals. However, chloramphenicol has until recently been widely available for oral, intramuscular or intravenous administration. A critical appraisal of the published literature on the use of chloramphenicol in the horse clearly demonstrates that there are sound pharmacokinetic and microbiological reasons for concluding that chloramphenicol is not an appropriate antibiotic for systemic use. The short half-life of chloramphenicol in the horse, together with the broad range of minimum inhibitory concentrations of target pathogens, preclude the use of practical dosage regimens. It can be concluded that the withdrawal of chloramphenicol will have no adverse effects on chemotherapy in the horse.  相似文献   
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