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41.
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Three techniques for the assessment of the integrity of the canine tympanic membrane were evaluated experimentally. Tympanometry, an objective technique, was shown to be very accurate for the evaluation of the integrity of the ear drum. Otoscopic examination by experienced personnel was shown to be moderately accurate under controlled conditions when the external ear canal was not inflammed. However, under field conditions when otitis externa was present, visual inspection of the tympanic membrane was seldom possible even after lavage of the ear. Palpation of the tympanic membrane with a blunt probe was shown to be very inaccurate and led to rupture of the tympanic membrane in a high proportion of cases. These results imply that two widely used techniques for the examination of the canine tympanic membrane are unsatisfactory. Furthermore, they suggest that previous reports of the prevalence of ear drum perforations in dogs may need reappraisal. Tympanometry is a non-invasive, objective and practical technique for the assessment of ear drum integrity which is worthy of further evaluation.  相似文献   
43.
A database of the clinical chemistry results from unwell animals referred to Glasgow University Veterinary School, by general practitioners, was studied. This database contains over 60,000 records, from more than 25,000 animals, obtained over a period of 18 years. A four-year period was selected during which the instruments and methods used for these analyses were unchanged. The biochemical analyses made on plasma from those dogs when first presented to the veterinary school were scrutinised in detail. These data have been summarised in a tabular form using the first, fifth, 10th, 25th, 50th, 75th, 90th, 95th and 99th percentiles. The distributions of these values differ for different analytes and in particular do not conform to a normal curve. These data can be used to provide estimates of rarity to indicate the frequency with which extreme values associated with disease can be expected. Thus an individual datum can be flagged as high*, high**, high***, or high**** depending on whether it lies in the top 25 per cent, top 10 per cent, top 5 per cent or top 1 per cent, respectively, of cases in the hospital database. Low values can be flagged in the same way. This approach can complement the use of reference ranges from healthy animals to aid the interpretation of clinical biochemistry results from a new patient.  相似文献   
44.
Serial sampling of bovine rib is undertaken experimentally to monitor changes in the degree of skeletal mineralisation. The validity of this approach depends on the assumption that the previous sampling of a bone does not influence the composition of a sample obtained subsequently. To test this, the effect of a prior biopsy sampling on phosphorus content of the remaining bone was determined at various times after the initial sampling. A preliminary biopsy sample was taken with a 1.5 cm diameter trephine from the left 12th rib of 40 cattle; experimental samples were taken from the same rib of 10 of the cattle at three, six, nine and 12 months later, for comparison with similar samples taken concurrently from the right 12th rib. The phosphorus content of the second left rib was significantly lower than that of the right (control) rib at the three-month interval, particularly where the sampling site was ventral, rather than dorsal, to the site from which the initial biopsy was obtained. No effects of previous biopsy sampling were observed after six, nine or 12 months.  相似文献   
45.
Effectiveness of post-harvest diphenylamine (DPA) dip treatments for superficial scald (scald) control is dependent on application method, DPA formulation, dip age, quantity of fruit throughput and the inclusion of additives (calcium chloride and fungicides).With bin-immersion systems, throughput up to 100 × 18 kg cases per 561 of dip, caused no loss of DPA. However, with an Australian miscible oil formulation DPA (M.O. Aust.) containing additives there was increased scald and lenticel spot (spot) after 50-case throughput, and with a wettable powder formulation DPA (P) there was increased spot after 50-case throughput, but these limitations were not apparent with an American miscible oil formulation DPA (M.O. U.S.). Replacing lost dip-volume with normal strength DPA after 50-case throughput prevented the occurrence of these disorders with further throughput. Dips which had had prior throughput and were then aged for 1–2 weeks were effective provided they were agitated before use.With bin-flooding systems using DPA (M.O. Aust.) or DPA (P), effective scald control was limited to the case throughput which was treated in 40–75 min. Exceeding this limitation caused the DPA (M.O. Aust.) emulsion to break down due to mechanical agitation in pumping, and DPA (P) to form a surface scum of DPA ingredient in the return tank. The DPA (M.O. U.S.) formulation was stable and effective in this system for at least 100 min pumping.  相似文献   
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REASONS FOR PERFORMING STUDY: Colic is a serious disease syndrome in horses. Much of the mortality is associated with ischaemic-injured intestine during strangulating obstruction, yet there is limited understanding of the associated molecular events. Identification of differentially expressed genes during ischaemic injury should expand our understanding of colic and may lead to novel targeted therapeutic approaches in the future. OBJECTIVE: To isolate and identify differentially expressed genes in equine jejunum following a 2 h ischaemic event compared to normally perfused jejunum. METHODS: Suppressive subtractive hybridisation was used to clone genes that are differentially expressed in equine jejunum injured by 2 h of complete ischaemia as compared to time-matched control jejunal tissues. Expression of selected clones was further evaluated by northern blot analysis. RESULTS: Of the 384 clones selected, 157 were confirmed to possess cDNAs corresponding differentially expressed genes by dot blot analysis. Two genes, fatty acid binding protein 2 and calcium-activated chloride channel 4 were further confirmed to be differentially expressed by northern blot analysis. CONCLUSIONS: Suppressive subtractive hybridisation can be used to detect changes in expression of a broad array of genes, as confirmed by northern blot analysis of selected genes. POTENTIAL RELEVANCE: These initial results have identified a pool of equine intestinal epithelial genes that are differentially expressed following a 2 h ischaemic event. In particular, genes indicative of deranged metabolic activity and those potentially involved in early repair events were identified and may ultimately provide clues as to the nature of epithelial ischaemic injury in horses.  相似文献   
48.
A Standardbred mare became paralyzed shortly after showing signs of an upper respiratory infection. The mare was euthanized and equine herpesvirus type 1 was isolated from the brain and spinal cord.  相似文献   
49.
Summary An investigation was made of the seasonal incidence of coccidial infection in West African Dwarf (WAD) goats in 2 villages and an on-station situation in the subhumid zone of Nigeria. Faecal samples were obtained from about 70 goats in each village and 160 on-station at 4 times of the year, early and late dry and wet seasons.Six species ofEimeria were found to occur;E. arloingi, E. apsheronica, E. pallida, E. alijevi, E. jolchievi andE. ninakohlyakimovae which accounted for 18, 16, 22, 9, 24, and 11% of infections respectively. Overall rates of infection were very high, averaging approximately 87%, and peaked during the late wet season, when the proportion of heavy infections also increased significantly. At this time the proportion of infections classified as heavy was significantly higher in the village goats than the on-station goats, and was also significantly higher in kids than in adults. Clinical disease only occurred in kids. The potential benefits of controlling such infections in terms of productivity responses appear worthy of further investigation in these farming systems.
Prevalencia De Infecciones Por Coccidia En Cabras Dwarf De Africa Occidental En La Zona Semihumeda De Nigeria
Resumen Se realizó una investigación sobre la incidencia estacional de infecciones por coccidia en cabras Dwarf (CD) en 2 villas y en una estación experimental en la zona semihúmeda de Nigeria. Se obtuvieron muestras fecales de 70 cabras en cada villa y 160 en la estación experimental, 4 veces en el año, al principio y al final de la estación seca y lluviosa.Se encontraron seis especies deEimeria; E. arloingi, E. apsheronica, E. pallida, E. alijevi, E. jolchievi yE. ninakohlyakimovae las que fueron la causa de 18, 16, 22, 9, 24 y 11% de infecciones respectivamente. Las tasas de infección generales fueron altas, promediando 87% aproximadamente, alcanzando el máximo pico al final de la estación lluviosa, cuando la proporción de infecciones se incrementó significativamente. En este momento las infecciones clasificadas como graves se presentaron más en las cabras de villorrio que en aquellas de la estación experimental, siendo también más graves en los cabritos que en los adultos. La enfermedad clinica solo se vió en los cabritos. La posibilidad de controlar la infección en términos de productividad, parece plausible de investigaciones adicionales en aquellas sistemas de crianza.

Prevalence Des Coccidioses Chez La Chevre Naine D'afrique De L'ouest En Zone Subhumide Du Nigeria
Résumé La recherche de l'incidence saisonnière de la coccidiose a été effectuée chez des chèvres naines d'Afrique de l'Ouest dans deux villages et en station dans la zone subhumide du Nigéria. Des prélèvements de fèces provenant de quelque 70 chèvres dans chaque village et 160 en station ont été faits 4 fois par an, en début et fin de saisons sèche et humide. Six espèces d'Eimeria ont été trouvées:E. arloingi, E. apsheronica, E. pallida, E. alijevi, E. jolchievi etE. ninakohlyakimovae qui représentaient respectivement 18, 16, 22, 9, 24 et 11 p. 100 des infections. Le taux global de l'infection était très élevé, environ 87 p. 100 en moyenne, et atteignait son maximum en fin de saison humide, lorsque le taux de parasitisme massif augmentait significativement. A ce moment la proportion des infections considérées comme massives était significativement plus élevée chez les chèvres villageoises que chez celles en station et était aussi significativement plus élevée chez les chevreaux que chez les adultes. La maladie clinique apparaissait seulement chez les chevreaux.
  相似文献   
50.
The case records of 20 horses with tetanus referred to the Ontario Veterinary College-Veterinary Teaching Hospital between 1970 and 1990 were reviewed. The fatality rate was 75%. There was a strong association with previous vaccination and survival ( P = .03). Most of the animals had been injured an average of 9 days (range 2 to 21 days) prior to development of clinical signs. Hyperesthesia and prolapse of the third eyelid were the most common clinical signs. Treatment regimens varied during hospitalization; however, all horses received parenteral penicillin, tranquilizers, tetanus toxoid, and antitoxin. Five of the nonsurviving animals were given intrathecal tetanus antitoxin. One animal had seizures as a complication of intrathecal treatment. The prognosis was best for horses that (1) had been vaccinated prior to the injury, (2) responded to the phenothiazine tranquilizers, and (3) did not rapidly (over 24 to 48 hours) become recumbent. Considering the species susceptibility, potential for contaminated wounds, and the increased survival of vaccinated horses, yearly revaccination is recommended.  相似文献   
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