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51.
This report describes a four-day-old, full-term Connemara colt, presented for the evaluation of a progressive inability to rise unassisted. A diagnosis of nutritional muscular dystrophy was made based on muscular weakness, elevated muscle enzymes and low vitamin E, selenium and glutathione peroxidase activity. The foal was treated with intramuscular vitamin E-selenium and made a full recovery.  相似文献   
52.
Objective To survey finches in pet shops for Cochlosoma infection and evaluate the efficacy of antiprotozoal therapy with metronidazole or ronidazole.
Design A survey of pet shop finches and drug efficacy trials.
Procedure Finches in pet shops were randomly selected and their faeces examined microscopically for motile Cochlosoma sp trophozoites. Drug trials were carried out on 60 adult finches with naturally occurring infections. Body weight was measured and the faeces of each bird was examined for trophozoites at the beginning and 7 days after the end of treatment. In some birds, additional daily faecal examinations were done until three consecutive negative results were obtained. Metronidazole was administered at various dose rates by crop gavage or in drinking water to eight groups of five to ten finches each. Ronidazole was given in water for 7 days to ten finches. In addition, six finches whose faeces tested positive were necropsied and their tissues collected for histological examination.
Results Motile flagellates in the faeces were identified as C anatis -like protozoa. Red-headed parrot-finches, Bengalese and Lady Gould finches were found to be most commonly infected. Cochlosoma sp was also found in the blue-faced parrot-finch, zebra finch, painted finch, nutmeg mannikin and double-barred finch. Metronidazole and ronidazole were found to be effective against Cochlosoma sp. Histological findings on infected adult finches were normal, except for the presence of numerous flagellates between the colorectal villi and cloacal mucosal folds.
Conclusions Cochlosoma anatis -like organisms can infect several species of finches and in adult finches are confined to the colorectum and cloaca. Infection in adult finches was mostly subclinical and could be treated effectively with metronidazole or ronidazole.  相似文献   
53.
Haematological and biochemical investigations were performed on 14 koalas with uncomplicated cystitis, 8 with complicated cystitis, 8 with conjunctivitis, 8 with lymphosarcoma, and 14 with miscellaneous diseases. Changes were limited and inconsistent in individual koalas with uncomplicated cystitis and conjunctivitis. In contrast, individual koalas with complicated cystitis were more likely to have anaemia, leukocytosis due to neutrophilia, hypoproteinaemia due to hypoalbuminaemia, and azotaemia due to elevated urea concentration. Although these changes were non-specific they did allow assessment of prognosis for survival and response to treatment. Koalas with lymphosarcoma were invariably anaemic, leukaemic, azotaemic and hypoalbuminaemic. Elevated enzymes (aspartate transaminase [AST]. lactate dehydrogenase [LD] and gamma glutamyl transferase [GGT]) were more common in koalas with lymphosarcoma. Koalas affected by miscellaneous conditions showed variable changes but once again anaemia, leukocytosis, azotaemia, elevated AST and LD, and hypoalbuminaemia were not uncommon. On the basis of these findings a minimal profile is suggested for the investigation of sick koalas and would include haematocrit, total and differential leukocyte counts, urea, total protein and albumin concentrations and AST, GGT and LD activities.  相似文献   
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55.
for wood manufacturers around the world, the single biggest cost factor is known to be its raw material. Maximum volume recovery of this raw material is, therefore, of key importance for the industry. The wood products industry consists of several interrelated manufacturing steps for converting trees into logs and logs into finished lumber. Each operation usually optimises its functionality in isolation from the preceding and following operations. It is a well documented fact that the optimisation of decisions through the whole chain of operations is considerably more profitable than the optimisation of individual operations. The objective of this study was to determine the optimal machine settings for two interrelated operations, namely the sawing and ripping operations which have tradition? ally been optimised individually. A model, having two decision variables, was developed which aims to satisfy market demand at a minimal cost. The first decision was how to saw the log supply into different thicknesses by choosing specific sawing patterns. The second was to decide on a rip saw's priority value settings, which determines how the products from the primary sawing operation are ripped into products of a certain thickness and width. The techniques used to determine the machine settings included static simulation with the SIMSAW software to represent the sawing operation and mixed integer programming to model the ripping operation. A metaheuristic, namely the Population Based Incremental Learning algorithm, was used to link the simulation and mixed integer models and to determine the optimal settings for the combined process. The model's objective function was to minimise the cost of production. This cost included the raw material waste cost and the over or under production cost. The over production cost included the stock keeping costs and the under production cost was estimated as the buy?in cost of under supplied products from another wood supplier. The model performed well against current decision software available, namely the Sawmill Production Planning System package, which combines simulation and mixed integer programming techniques to maximise profit. The model added further value by modelling and determining the ripping priority settings in addition to the primary sawing patterns.  相似文献   
56.
Forty three koalas in a captive colony were investigated for the presence of Chlamydia psittaci infection and associated disease. Swabs were taken from conjunctivae and urogenital sites for cell culture isolation of C psittaci and for cytological examination (direct smears) for chlamydial inclusions and evidence of inflammation. On the basis of cell culture isolation, 28 samples from 25 koalas were positive for C psittaci (that is, infected). Three koalas were positive from both sites, 5 from conjunctivae alone and 17 from urogenital sites alone. Seven of the 8 koalas with positive conjunctival swabs had overt signs of conjunctivitis, but only 3 of the 20 koalas with positive urogenital swabs had overt signs of 'wet bottom' (continual urine soiling due to cystitis) or purulent discharge. However, 5 of the 20 with positive urogenital swabs had past episodes of 'wet bottom'. Moreover, examination of direct cytological smears showed evidence of inflammation (neutrophils) in 7 of 8 koalas with positive conjunctival swabs and 17 of 20 with positive urogenital swabs. Chlamydial inclusions were rarely identified with surety on direct cytological smears. In the 18 koalas without chlamydia, one had overt conjunctivitis while 2 had past episodes of conjunctivitis. The koala with conjunctivitis at the time of sampling had a prior history of 'wet bottom'. Examination of direct cytological smears revealed 2 of the chlamydial negative koalas had high numbers of neutrophils in urogenital smears. It was concluded that C psittaci infection may cause overt or sub-clinical disease, with the former developing when the koalas were stressed through management procedures or concomitant disease.  相似文献   
57.
The toxicity of pindone, a rabbit poison, to horses, cattle, goats, chickens, dogs and cats was investigated, using extension of prothrombin time (PT) as an index of poisoning. The daily dose of pindone, administered for 5 days, ranged from 0.3 mg/kg for dogs to 2.5 mg/kg for chickens. This range of dose rates was considered to be indicative of the worst possible case that could arise following a campaign of baiting for rabbits. Although significant elevations in PT (more than double baseline values) were noted in all species other than horses, clinical signs of anticoagulant poisoning were not observed in any of the species tested. From the observed PT, cattle and cats appeared to be the most susceptible, and horses the least susceptible, to pindone toxicity. The half-lives of the elevated PT were calculated as 3.1 days for cattle, 2.8 days for goats and chickens, 1.9 days for horses and dogs and less than one day for cats. It is proposed that these half-lives can be used as a guide for determining the duration of treatment of pindone-affected animals.  相似文献   
58.
Objective   To determine the efficacy of triclabendazole (TCBZ) against 28-day-old, early immature liver fluke in cattle and its pharmacokinetics following administration by the oral or topical (pour-on) route.
Procedures   Cattle (n = 18) were infected with 500 TCBZ-susceptible liver fluke metacercariae and randomly allocated to three groups. At 28 days after infection, the groups were: (1) untreated controls; (2) treated with oral TCBZ at 12 mg/kg in combination with oxfendazole and selenium (TOS); (3) treated with pour-on TCBZ at 30 mg/kg in combination with abamectin (TA). Blood samples were taken immediately prior to treatment and serially after treatment to assess the plasma profile of TCBZ metabolites. Ten weeks after treatment all animals were slaughtered and total liver fluke counts, fluke egg counts and liver pathology were assessed.
Results   Both the TOS and TA treatments resulted in significant reductions of 28-day-old liver fluke, as assessed by fluke counts and fluke egg counts at slaughter, and the reductions following TOS treatment were significantly greater than those following TA treatment. The blood profile of TCBZ metabolites in TOS-treated animals showed a significantly greater area under the plasma concentration time curve and a higher maximum observed concentration than those treated with TA. There was significantly less liver pathology in TOS-treated animals than in the TA-treated animals.
Conclusion   TCBZ administered orally at 12 mg/kg resulted in greater efficacy against 28-day-old, early immature liver fluke than was achieved by topical administration at 30 mg/kg. Plasma metabolites of TCBZ were higher and liver pathology was less in TOS-treated animals than in TA-treated animals.  相似文献   
59.
Haematological investigation is an important part of disease diagnosis. This is particularly so when investigating individual animal disease. It may also be important when investigating diseases in groups of animals, but the opportunity to perform necropsies to directly detect disease processes often diminishes its usefulness. Haematological investigation is essentially similar for all species. The presence of nucleated erythrocytes and thrombocytes in nonmammals requires alteration of haemoglobin measurement and cell counting. In addition, it may cause some confusion in identification of cells in peripheral blood films. Examination of blood films is an important component of haematological investigation and provides useful information on erythroid, leukocytic and platelet/thrombocytic alterations. Interpretation of alterations is essentially similar for all species. However, cell identification can at times be difficult. There are five basic leukocytes in all species: neutrophil (mammals) or heterophil (nonmammals), eosinophil, basophil, lymphocyte and monocyte. In nonmammals it may be difficult at times to distinguish between heterophils and eosinophils. In addition, lymphocytes may be confused with thrombocytes. However, a common-sense approach to the examination of the peripheral blood film will minimise this confusion.  相似文献   
60.
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