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991.
P. K. Randleff-Rasmussen A. Leblond J. Cappelle J. Bontemps S. Belluco M. R. Popoff C. Marcillaud-Pitel J. Tapprest P. Tritz I. Desjardins 《Veterinary research communications》2018,42(1):19-27
Equine grass sickness (EGS) (equine dysautonomia) is a neurodegenerative condition of grazing equines. Pre-mortem diagnosis of EGS is a challenge for practitioners as definitive diagnosis requires ileal/myenteric lymph node biopsies. This study aimed to develop a clinical score that could be used by practitioners to improve the detection of acute or subacute EGS cases in the field. Suspected EGS cases were declared by veterinary practitioners. A case was classified as confirmed positive if ileal or rectal biopsy samples showed neuronal degeneration typical of EGS. A semi-quantitative scoring system, including epidemiological and clinical data, was created to attempt to classify suspected EGS horses into confirmed positive or negative cases. Each variable was weighted based on a boosted regression trees model, while taking into account its clinical relevance. Twenty-eight EGS cases were confirmed by biopsy during the entire study period. The best cut-off value for the score to have a high sensitivity while maximizing specificity was 8, with a sensitivity of 100% and a specificity of 53%. In our dataset, 77% of animals would be correctly classified with this cut-off value of 8. Highest sensitivity was chosen in order to detect the highest number of potential cases. Our score represents an inexpensive and useful tool to aid in the identification of suspected EGS cases in the field and selection for further diagnostics procedures to confirm or rule out the disease. Application of the score to larger populations of animals would be required to further adapt and refine the score. 相似文献
992.
T. D. Procter D. L. Pearl R. L. Finley E. K. Leonard N. Janecko R. J. Reid‐Smith J. S. Weese A. S. Peregrine J. M. Sargeant 《Zoonoses and public health》2014,61(3):208-218
An estimated 6 million pet dogs live in Canadian households with the potential to transmit zoonotic pathogens to humans. Dogs have been identified as carriers of Salmonella, Giardia and Campylobacter spp., particularly Campylobacter upsaliensis, but little is known about the prevalence and risk factors for these pathogens in pet dogs that visit dog parks. This study examined the prevalence of these organisms in the faeces of dogs visiting dog parks in three cities in south‐western Ontario, as well as risk factors for shedding Campylobacter spp. and C. upsaliensis. From May to August 2009, canine faecal samples were collected at ten dog parks in the cities of Guelph and Kitchener‐Waterloo, Ontario, Canada. Owners were asked to complete a questionnaire related to pet characteristics and management factors including age, diet and activities in which the dog participates. Faecal samples were collected from 251 dogs, and 189 questionnaires were completed. Salmonella, Giardia and Campylobacter spp. were present in 1.2%, 6.4% and 43.0% of faecal samples, respectively. Of the Campylobacter spp. detected, 86.1% were C. upsaliensis, 13% were C. jejuni and 0.9% were C. coli. Statistically significant sparing factors associated with the shedding of Campylobacter spp. included the feeding of a commercial dry diet and the dog's exposure to compost. Age of dog had a quadratic effect, with young dogs and senior dogs having an increased probability of shedding Campylobacter spp. compared with adult dogs. The only statistically significant risk factor for shedding C. upsaliensis was outdoor water access including lakes and ditches, while dogs >1 year old were at a lower risk than young dogs. Understanding the pet‐related risk factors for Campylobacter spp. and C. upsaliensis shedding in dogs may help in the development of awareness and management strategies to potentially reduce the risk of transmitting this pathogen from dogs to humans. 相似文献
993.
Poxvirus infections are common in domestic birds in Germany, but they are rare in birds of prey. Only species of falconidae imported from Arabian or Asian countries have so far tested positive for poxvirus, and, among these, only raptors kept for falconry. As part of a reintroduction programme in the northern county of Mecklenburg-Western Pomerania, which is adjacent to the Baltic Sea, 21 young peregrine falcons were released into the wild; six of them died and one was examined postmortem, its tissues being examined by light and electron microscopy. In addition, an ELISA for fowlpox, pigeonpox and canarypox was applied. No virus could be isolated and propagation in culture failed, but virus particles were detected by electron microscopy in lesions from its skin and tongue. 相似文献
994.
Infectious bovine keratoconjunctivitis II. Antibodies in lacrimal secretions of cattle naturally or experimentally infected with Moraxella bovis. 下载免费PDF全文
One or both eyes of 20 calves were inoculated one or more time with variou(s combinations of microorganism (live oor killed Moraxella bovis, infectious bovine rhinotracheitis virus, bovine adenovirus, bovine parainfluenza-3 virus and Mycoplasma bovoculi) by conjunctival instillation or direct inoculation of the conjunctivea or cornea. The eyes of all the calves received natural or artificial ultraviolet irradiation. Neither the adenovirus nor parainfluenza-3 virus became established in the eye or produced keratoconjunctivitis. Both M. bovis and infectious bovine rhinotracheitis virus became established in the bovine eye and produced disease. Subconjunctival or intracorneal inoculation of M. bovis caused a severe disease, simulating natural infectious bovine keratoconjunctivitis. Only the intracorneal inoculation of mycoplasma produced severe keratoconjunctivits. Eyes that on initial exposure to M. bovis became severly inflamed were more resistant to a second or third exposure to M. bovis, presumably by enhanced local defence mechanisms. 相似文献
995.
S Oikawa N Katoh H Itoh T Miyamoto M Konno T Kajita 《Canadian journal of veterinary research》1997,61(3):182-186
Serum apolipoprotein A-I concentrations in cows infected with Salmonella Typhimurium were evaluated to assess its relevance in salmonellosis. Apolipoprotein A-I has been shown in rats to be secreted by the intestine as well as the liver. Clinical symptoms such as diarrhea revealed an outbreak of salmonellosis in 22 cows on a farm, and sera were obtained at 6 (acute phase), 16, 28 (convalescent period) and 42 d (postconvalescent period) after the outbreak. Apolipoprotein A-I concentrations (mean +/- SD, mg/mL), determined by ELISA, were 0.598 +/- 0.497 (day 6), 0.111 +/- 0.060 (day 16), 0.432 +/- 0.311 (day 28) and 0.727 +/- 0.516 (day 42). Compared with the concentration at day 42, those at 16 and 28 d were significantly (P < 0.01, P < 0.05) lower, but that at day 6 was not. The serum concentration of apolipoprotein B-100 (of liver origin in cattle) was unaltered during the course of salmonellosis. The concentration of apolipoprotein A-I was positively correlated with those of serum total cholesterol (r = 0.589, P < 0.01) and phospholipids (r = 0.590, P < 0.01). These results suggest that apolipoprotein A-I in cattle is in part of intestinal origin, and also that its decreased serum concentration in salmonellosis can be attributed to the reduced intestinal synthesis or secretion of this apolipoprotein. Moreover, as a potential carrier for dietary lipids such as cholesterol, determination of serum apolipoprotein A-I concentration is suggested to be useful when assessing the nutritional status of the affected cows. 相似文献
996.
Kazwala R.R. Daborn C.J. Kusiluka L.J.M. Jiwa S.F.H. Sharp J.M. Kambarage D.M. 《Tropical animal health and production》1998,30(4):233-239
A study to determine the secretion of Mycobacterium spp. in milk from indigenous cattle was carried out in pastoral cattle reared in the Southern Highlands of Tanzania. The study was aimed at elucidating the dangers associated with milk-borne zoonoses in a society where milk is normally consumed raw. Out of 805 milk samples, 31 (3.9%) were positive for mycobacteria. There was a preponderance of atypical mycobacteria (87%) whereas only two isolates (6.5%) were confirmed as M. bovis. Atypical mycobacteria included: M. terrae (n=7), M. fortuitum (n=2), M. flavescens (n=13), M. gordonae (n=1) and M. smegmatis (n=4). Although the number of M. bovis positive samples was low, the habit of pooling milk may still pose great public health dangers to milk consumers in this part of the world. Moreover, isolation of atypical mycobacteria should also be considered to be a danger to human health in countries such as Tanzania, where the number of people with lowered immunity due to HIV infection is on the increase. 相似文献
997.
K. M. Pratschke J. M. L. Hughes C. Shelly C. R. Bellenger 《The Journal of small animal practice》1998,39(1):33-38
Three of four cases of chronic diaphragmatic herniation seen over a period of 12 months developed hiatal herniation within five to eight days of corrective surgery for the diaphragmatic herniation. None of the dogs had shown any prior signs referrable to hiatal herniation. The features that developed subsequent to diaphragmatic herniorrhaphy in all cases were dyspnoea, increased intra-abdominal pressure due to decreased abdominal domain and laxity of the oesophageal hiatus as judged subjectively at the time of surgery for hiatal herniation correction. These conditions may be significant underlying factors for the development of hiatal herniation not preceded by diaphragmatic herniation in the dog. Those associated factors accepted as important in humans, including reduced lower oesophageal sphincter tone and gastroesophageal reflux, may not be of similar importance in small animals. 相似文献
998.
Cherax albidus (A) and Cherax destructor (D) male juveniles (mean weight 0.95 ± 0.03 g) were reared for 20 weeks on isoenergetic diets containing 150 g kg?1 protein (A 15, D15) or 300 g kg?1 protein (A30, D30). Mean weight, percentage weight gain, and specific growth rate (%) were substantially higher for both species on the 300 g kg?1 protein diet. Mean percentage weight gain ranged from 2.39% day?1 (D15) to 17.59% day?1 (A30). A maximum weight of 33.81 g was attained by C. albidus on the higher protein diet. The most effective utilization of food was observed in C. albidus when fed the higher protein diet (food conversion ratio, 0.79; protein efficiency ratio, 4.21; apparent net protein utilization, 44.64%). Carcass composition was influenced by feed type. The higher protein diet resulted in an increase in carcass protein and ash and a decrease in carcass lipid and energy relative to the low-protein diet (150 g kg?1 protein diet –C. albidus: 37.15% protein, 15.00% lipid, 25.20% ash, 15.55kJ g?1 energy; C. destructor: 38.10% protein, 15.43% lipid, 25.70% ash, 15.65kJ g?1 energy; 300 g kg?1 protein diet –C. albidus: 46.10% protein, 8.71% lipid, 27.36% ash, 14.94kJ g?1 energy; C. destructor: 42.99% protein, 8.56% lipid, 26.44% ash, 14.71kJ g?1 energy). Carcass moisture and calcium were not affected by feed type. The time spent in the intermoult phase of growth was highly dependent on the premoult weight and varied according to diet and to species. A comparison of animals of similar weight (< 8 g) revealed that elevated dietary protein caused a reduction in the intermoult period by 11 days in C. albidus and 7 days in C. destructor. The moult increment, however, was independent of animal weight, and the highest percentage weight increment occurred for C. albidus fed the 300 g kg?1 protein diet (per cent weight increase; A15, 33.1%; A30, 61.3%; D15, 31.2%; D30, 56.5%). Dietary induced morphological changes were also recorded. Animals of a standard carapace length had significantly larger abdomens (both species) and larger claws (C. albidus) when fed the higher protein diet. 相似文献
999.
Yazawa M Okuda M Setoguchi A Iwabuchi S Nishimura R Sasaki N Masuda K Ohno K Tsujimoto H 《American journal of veterinary research》2001,62(10):1539-1543
OBJECTIVE: To measure telomere length and telomerase activity in naturally occurring canine mammary gland tumors. SAMPLE POPULATION: 27 mammary gland tumor specimens obtained during resection or necropsy and 12 mammary gland tissue specimens obtained from healthy (control) dogs. PROCEDURE: Telomere length in tissue specimens was measured by use of restriction endonuclease digestion and Southern blot analysis. Telomerase activity was measured by use of a telomeric repeat amplification protocol assay. RESULTS: Telomere length in mammary gland tumors ranged from 11.0 to 21.6 kilobase pairs (kbp; mean +/- SEM, 14.5+/-0.5 kbp) but did not differ among tumor types. Telomeres in mammary gland tumors were slightly shorter than in normal tissue specimens, but telomere length could not be directly compared between groups, because mean age of dogs was significantly different between groups. Age was negatively correlated with telomere length in control dogs but was not significantly correlated with length in affected dogs. Telomerase activity was detected in 26 of 27 mammary gland tumors and in 4 of 12 normal tissue specimens. However, telomerase activity and telomere length were not correlated in tumor specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Telomere length is maintained in canine mammary gland tumors regardless of the age of the affected dog. Measurement of telomere length may be a useful tool for monitoring the in vivo effects of telomerase inhibitors in dogs with tumors. 相似文献
1000.
K. Shiomitsu E. Sajo X. Xia D. W. Hunley G. E. Mauldin S. Li G. N. Mauldin 《Veterinary and comparative oncology》2008,6(3):193-200
The p53 gene is one of the important tumour suppressor genes that are involved with the cell survival signal pathway. One of the major functions of the p53 protein is to organize cell cycle regulation and induction of apoptosis for cellular genetic stability. It has been documented that more than 50% of all human cancers include a p53 mutation. We evaluated the difference in radiosensitivity between upregulating the expression of canine wild‐type p53 (cp53) in cultured osteosarcoma (D17) cells and naive D17 cells in vitro. We found that upregulating transfected cp53 D17 cells increased their radiation sensitivity in vitro, and there was a significant decrease (P < 0.009) in survival between cp53‐transfected D17 cells and naive D17 cells. In this experiment, a p53 enhancement ratio (p53ER) reached approximately 3.0 at high doses. The transfected cp53 D17 cells were significantly more radiosensitive at all doses evaluated than naive D17 cells, except at 1 Gy where too few data points were available. The p53ER increased rapidly at doses less than 4 Gy, achieving a maximum of about 3.0 for doses of 4 Gy and above. This study shows the enhanced radiosensitivity of the transfected p53 at clinically relevant doses. 相似文献