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1.
Rust (Tranzscheliu discolor) is the most important disease of French prunes in New South Wales (NSW), Australia. Infection by this fungus occurs only when leaves are wet. The length of time for which the leaves are wet and the temperature during such periods are major determinants of whether infection occurs and its likely severity. The use by prune growers of new rust management strategies depends on knowledge of infection events and therefore requires ready access to environmental data from orchards. To satisfy this need, microprocessor-based device called a Prune Rust Infection Predictor (PRIP) was developed. The instrument measures air temperature, rainfall, and the presence or absence of free water tree canopies. Measurements are taken at 5-min intervals during wet periods. The instrument calculates whether or not conditions have been suitable for rust infection and potential severity of infection. The system has been operated by advisory staff of NSW Agriculture Fisheries since the 1988/1989 growing season. Potential infection period and related environmental data are collected by personal computers via permanently installed telephone lines from PRIPs located within prune orchards. Prune growers are then advised by recorded telephone messages and given appropriate disease mangement advice. Cumulative potential infection period values are used to provide a prognosis of current-season rust epidemic severity. An expert system is also being developed to assist growers in making decisions on specific rust management options.  相似文献   
2.
Objective To compare different methods for assessing the compliance of veterinary clients administering medication to their dogs.
Procedure Thirty-one owners whose dogs were prescribed amoxycillin-clavulanate, twice and thrice daily, for a duration of five to seven days were recruited from three Sydney veterinary hospitals. Compliance was assessed by electronic monitoring devices, return medication counts, client self-reports and veterinarians' estimation of likely compliance.
Results Electronic monitoring showed owners administered on average 84% (range 7 to 104%) of prescribed medication to their dogs. Both return medication counts and client self-reports tended to overestimate therapeutic compliance when compared with electronic monitoring. When questioned, the majority of owners (71%) claimed perfect compliance with the prescribed regimen. No correlation was found between veterinarians' estimates of owner compliance and that assessed electronically.
Conclusion Electronic monitoring provided valuable information on dose timing and variation, but proved costly and difficult to employ in veterinary practice. Simplicity and low cost of return medication counts makes this method attractive for use in veterinary compliance studies. Client self-reports reliably detected some noncompliers and permitted identification of individual problems or errors. For practical purposes a combination of return medication counts and client self-reports may have merit in future veterinary compliance studies.  相似文献   
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Objective To characterise the effects of delmadinone acetate on the pituitary-adrenal axis, glucose tolerance and growth hormone concentration in normal male dogs and dogs with benign prostatic hyperplasia.
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined.  相似文献   
5.
Objective To compare cortisol responses to three corticotrophic preparations in normal dogs.
Animals Eight clinically normal dogs (four intact males, four intact females) of medium size.
Procedures Each dog received four treatments on four separate occasions in a duplicated Latin square pattern. Treatments were two adrenocorticotrophin (ACTH) preparations given intramuscularly at 2.2 U/kg, one of the ACTH preparations given intramuscularly at 1 U/kg and a synthetic polypeptide with ACTH-like activity (tetracosactrin, cosyntropin) given intravenously at 5 μg/kg. Plasma samples were taken for cortisol assay before and at 0.5, 1, 2 and 4 h after treatment.
Results Plasma cortisol concentrations were similar with the two ACTH preparations and at both dose rates. Tetracosactrin produced smaller mean peak cortisol concentrations, which tended to occur earlier than with ACTH, and smaller values for the area under the curve of plasma cortisol concentration from zero time to 4 h.
Conclusion The findings suggest that canine adrenal function can be tested adequately by giving ACTH intramuscularly at 1 U/kg and measuring plasma cortisol in samples taken at 0 and 2 h, or by giving tetracosactrin intravenously at 5 μg/kg and determining cortisol concentration at 0 and 1 h.  相似文献   
6.
VOGELGSANG  WATSON  DITOMMASO  HURLE 《Weed Research》1998,38(3):175-182
The effects of the fungal pathogen Phomopsis convolvulus Ormeno on seedling and established plant performance of Convolvulus arvensis L. were compared under both controlled and field conditions. Under a controlled environment, a granular barley formulation of the fungal inoculum that had been applied on to the soil surface of pots containing pre-germinated C. arvensis seeds resulted in above-ground biomass reductions of up to 87%. However, application of the fungus to established plants that had been cut to ground level produced biomass reductions (43%) that were nearly half of those obtained for seedlings. In a parallel field experiment conducted over two growing seasons, application of P. convolvulus resulted in dramatic above-ground biomass reductions for both seedlings and established plants. In one trial, biomass reductions of up to 100% and 98%, respectively, were obtained. C. arvensis coverage within field plots was closely correlated with above-ground biomass. Findings in this study indicated that P. convolvulus may provide effective control of C. arvensis when applied pre-emergence.  相似文献   
7.
In two experiments conducted with Ayrshire dairy cows in 1974 and 1975 on swards of S23 perennial ryegrass, four systems of continuous grazing were investigated. The leys received 345 and 370 kg ha-1 fertilizer nitrogen in 1974 and 1975 respectively and were stocked at the rate of five cows per ha. In 1974, a comparison was made between two systems which either integrated silage making with, or separated it from, the continuous grazing. The provision of a silage aftermath in late July increased milk yield after that time, but had no significant effect on milk yield over the 19-week experimental period. In 1975, a comparison between weekly and monthly applications of fertilizer N showed no significant differences between milk yields in a 20-week period. The feeding of supplementary concentrates from late July onwards significantly increased milk yield. The treatments in both years had only small and mainly non-significant effects on milk composition. On average, excluding the concentrate treatment, the annual output of milk was 10,800 kg ha-1 using spring-calved cows.  相似文献   
8.
Grass silage made in late May from S24 perennial ryegrass was offered to twelve Ayrshire cows in a 16-week feeding experiment. The silage had a DM content of 25.3%, a pH of 3.91, and contained 16.8% CP and 68.4% digestible organic matter in the DM. The silage was fed ad libitum and was the sole feed in the control treatment. In the other three treatments the silage was supplemented with a cube offered at rates of 0.8, 1.4 and 2.0 kg per 10 kg milk. The cube contained 82.2% groundnut, plus molasses and minerals, and had 37.9% CP in the DM. The daily intake of silage DM was 11.4 kg per cow on average over the four treatments which did not differ significantly. The mean daily milk yields were 14.8 kg per cow in the control treatment, and 16.5, 18.2 and 18.4 kg in the 0.8, 1.4 and 2.0 kg supplement treatments respectively. The SNF, CP and lactose contents of the milk were Wghest on the 1.4 kg supplement treatment. It is concluded that with a high digestibility silage, there is little evidence to support the feeding of more than 1.4 kg of high-protein cubes per 10 kg milk in the declining phase of lactation.  相似文献   
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An 8-year-old, spayed female Labrador Retriever, which had been treated with oestrogens for urinary incontinence, developed non-pruritic, bilaterally-symmetrical alopecia and skin hyperpigmentation, with enlargement of mammary glands and vulva. Skin biopsy changes were consistent with an endocrine alopecia, hypothyroidism and hyperadrenocorticism were excluded by hormonal tests. Oestrogen-induced alopecia was suspected and hormonal treatment withdrawn. Two months later, hair regrowth was almost complete and genital changes were lessened.  相似文献   
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