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61.
A questionnaire was sent to 238 members of local pig discussion groups in the West Midlands region of England to identify farm level factors associated with the occurrence of diarrhoea in grower-finisher pigs. The questions related to the occurrence, diagnosis and aetiology of scour problems on the farm, the prevalence of common porcine diseases on the farm, the classes of pigs, staff employment, source of replacement stock and biosecurity measures, the husbandry techniques such as piglet management, use of medication, movement and mixing of pigs, dung removal and pen preparation between batches of pigs, and the physical resources such as floor type, pen divisions, watering, feeding and dung disposal systems. Replies from 105 producers keeping grower-finisher pigs were included in the analysis, 50.5 per cent of which had had a scour problem at some time in the previous three years. The causes of scour had been identified as colitis (34.3 per cent), swine dysentery (10.5 per cent) or porcine enteropathy (3.8 per cent). There was a significant association between the following factors and the occurrence of diarrhoea in grower-finisher pigs: the use of water medication for weaners (odds ratio = 11.8; P = 0.002), the tail-docking of piglets (odds ratio = 8.6; P = 0.003), the use of a wet feeding system for finishers (odds ratio = 5.9; P = 0.009), finishers housed on partially slatted floors (odds ratio = 3.6; P = 0.044), and the use of an isolation procedure for incoming breeding stock involving exposure to dung (odds ratio = 3.5; P = 0.046). The use of disinfectant in the preparation of pens between batches of pigs appeared to be protective (odds ratio = 0.3; P = 0.046).  相似文献   
62.
OBJECTIVE: To describe and compare the distribution of technetium Tc 99m (99mTc) pertechnate following intraosseous or i.v. injection (with or without use of a tourniquet) in the distal portion of the forelimb in standing horses. ANIMALS: 4 horses. PROCEDURE: Each horse received 4 forelimb treatments in random sequence: intraosseous infusion with tourniquet application (IOT), intraosseous infusion without tourniquet application, i.v infusion with tourniquet application (IVT), and i.v. infusion without tourniquet application. Dynamic nuclear scintigraphic imaging of the third metacarpal bone, proximal and middle phalanges, and distal phalanx was performed from the start of each treatment until 1 hour after infusion was completed. Radionuclide activity was compared within and between treatment groups. RESULTS: Tourniquet application was necessary to maintain high levels of radionuclide activity in the distal portion of the forelimb after intraosseous or i.v. infusion with 99mTc pertechnate; IVT and IOT treatments resulted in similar radionuclide activity in the proximal and middle phalanges and distal phalanx. Of the 4 treatments, there was significantly higher radionuclide activity in the distal aspect of the third metacarpal bone after the IOT treatment. CONCLUSIONS AND CLINICAL RELEVANCE: By use of a tourniquet, radionuclide administration via the intraosseous or i.v. routes resulted in effective perfusion of the distal portion of the forelimb and similar distribution of the agent in the phalanges of horses. Further studies are required to ascertain whether these findings apply to delivery of therapeutic agents in infected tissues via IOT or IVT.  相似文献   
63.
Regional suppurative meningoencephalitis and ventriculitis of variable chronicity was diagnosed in three young dogs residing in Colorado. Grass awns were grossly identified in the right occipital cortex of one dog and in the right lateral ventricle of another. Intralesional plant material was microscopically evident in the dura mater overlying the right occipital cortex of the third dog. One grass awn was identified as a floret of Hordeum jabatum. In each case, aerobic culture of brain tissue identified multiple isolates of bacteria. The dogs presented with clinically variable, rapidly progressive neurologic dysfunction, including tetraplegia, depressed mentation, and episodic extensor rigidity, ataxia, circling, stupor, vocalization, and head-pressing. Encephalitis due to bacteria introduced from migrating plant foreign material is a potential sequela of intranasal, periocular, or pharyngeal foreign bodies.  相似文献   
64.
OBJECTIVE: To determine reasons for epidural catheter placement among horses examined at a veterinary teaching hospital, efficacy of epidural administration of analgesics, duration of catheter placement, reasons for catheter removal, and complications encountered. DESIGN: Retrospective study. ANIMALS: 43 horses. PROCEDURE: Medical records were reviewed. RESULTS: A total of 50 epidural catheters were placed in the 43 horses. Underlying conditions included fractures, lacerations, septic arthritis, myositis, perineal injuries, and cellulitis. Horses ranged from 2 to 21 years old and weighed between 365 and 795 kg (803 and 1,749 lb). Median duration of catheter placement was 96 hours (range, 1.5 to 480 hours). The response to epidural drug administration was reported as positive in 34 horses and negative in 4. There was no apparent response in 2 horses, and response could not be determined in 3. Three temporary patient-related complications associated with epidural catheter administration were observed. Technical problems associated with the epidural catheters included dislodgement of the catheter itself (7 catheters) or of the adapter or filter (5), obstruction (5), and leakage (5). Twenty-two catheters were removed because of resolution of the underlying condition, and 10 were removed because of complications. For 6 catheters, the reason for catheter removal was not recorded. The remaining 12 catheters were in place when the horses were euthanatized. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that epidural catheterization can be used successfully for repeated epidural delivery of analgesics and anesthetics in horses with various clinical conditions. Complications associated with epidural catheters or epidural drug administration were infrequent and transient.  相似文献   
65.
66.
Imazapyr owes its importance in Morocco to its success in controlling the perennial weed Solanumelaeagnifolium Cav., which infests the Tadla area. Persistence and mobility of imazapyr has been studied in two Moroccan soils from the Rabat area, with differing organic matter content (red and organic soils), under laboratory conditions at 75% of their field capacities and 25–28 °C. Residue analysis was performed on the basis of a bioassay test using lentil (Lens culinaris Medic.) as indicator species. The residual activity of imazapyr accounted for 69%, 25%, 50% and 62%, 46%, 66% of the initial activity for the red and organic soils at 1, 5 and 10 mg L?1 respectively. The half-lives varied between 25 and 58 days for the red soil and 55 and 58 days for the organic soil. In the organic soil, imazapyr was highly mobile under the irrigation regime applied. Most of the activity was found in the first 3 × 75 mL of the effluents. A following biotest with the leached soil showed low remaining residual activity.  相似文献   
67.
1. Varying degrees of biotin deficiency were induced by adding freeze‐dried, raw egg white to the diet of broiler chicks. Aspects of liver metabolism were studied with reference to fatty liver and kidney syndrome.

2. Mortality was low with 11 .8 g egg white/kg diet, or less, but with 17.7 g/kg or more, mortality was very high. High mortality was observed with less than 0.33 μg biotin/g liver.

3. Associated with low concentrations of liver biotin were substantial increases in liver weight and lipid content in starved birds. The increased liver lipid content was not observed in birds fed ad libitum.

4. The increased liver lipid content in biotin‐deficient, starved birds was not reflected in the specific activities of hepatic lipogenic enzymes or hepatic lipogenesis in vivo measured by the incorporation of tritium from 3H‐labelled water into liver lipid.

5. Biotin deficiency affected the specific activities of the biotin‐requiring enzymes, pyruvate carboxylase and acetyl CoA carboxylase, differently; the latter was unaffected whereas the former decreased concomitantly with liver biotin concentration.  相似文献   

68.
Residues of DDT were detected in 76 of 101 samples of rainwater collected during spring and summer at several sites in the Province of New Brunswick in 1967 and 1968, and at one site in the Magdalen Islands, Quebec, in 1968. The dominant residue was p,p'-DDT. Levels of DDT and metabolites combined ranged from less than 0.01 to 1.33 microgram/kg. Levels of DDT and metabolites in the pollen of four species of forest trees in New Brunswick ranged from 0.544 to 1.01 mg/kg; such contaminated pollen possibly contributed to residues in rainwater. Residue data for rainwater from two sites were used to estimate the amount of DDT aerially transported into the Gulf of St. Lawrence during July to October 1968.  相似文献   
69.
Organochlorine and mercury concentrations are reported for 252 eggs of Leach's storm-petrel (Oceanodroma leucorhoa), double-crested cormorant (Phalarocorax auritus), common eider (Somateria mollissima), common tern (Sterna hirundo), razorbill (Alca torda), common murre (Uria aalge) black guillemot (Cepphus grylle), and Atlantic puffin (Fratercula arctica) from the Bay of Fundy, the Gulf of St. Lawrence, and the open Atlantic shore of Canada during 1970-76. Concentrations of all organochlorines except DDE and polychlorinated biphenyls (PCBs) were low. DDE, PCBs, and mercury residues were highest in cormorant and petrel, intermediated in alcids, and lowest in eider and tern. Temporal and spatial aspects of contamination patterns are discussed. Authors conclude that only in cormorants were DDE residues high enough to cause, through eggshell thinning, local population declines.  相似文献   
70.
Severe combined immunodeficiency disease (SCID) of horses is an autosomal, recessive hereditary disease occurring among Arabian or crossbred Arabian horses. The genetic defect responsible was previously identified as a 5‐base pair deletion in the gene encoding the catalytic subunit of the DNA dependant protein kinase (DNA‐PKcs). This study was carried out to determine the frequency of SCID and identify horses carrying the gene for SCID among Arabian and Arabian crossbred stallions and mares in Morocco using a DNA‐based test. Twenty‐one horses were SCID carriers: 14 (7%) Arabians, 6 (4%) Arab‐Barbs and one (3.3%) Anglo‐Arab. After analysing their genealogy, 3 imported stallions were identified that disseminated the mutant gene of DNA‐PKcs in Morocco.  相似文献   
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