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991.
Couacy-Hymann E Bodjo SC Danho T Koffi MY Libeau G Diallo A 《Preventive veterinary medicine》2007,78(1):85-88
We observed 15 goats for 9 days after subcutaneous infection with 10(3) TCID(50) with isolates of peste-des-petits ruminants virus from Africa and India and five concurrent, uninfected control goats. Typical clinical signs of the infection were present in all 15 infected goats by day 8 and in most by day 6 and some signs were present by day 4. However, 6 out of 15 goats already have detectable virus shedding by day 3 and four more were shedding by day 4 and every goat had virus shedding for at least 1 day before the recognition of clinical signs. This experiment indicates that incubatory carriers therefore might play a role in the transmission of PPRV among small ruminants. 相似文献
992.
Emergency preparedness relies on the ability to detect patterns in rare incidents in an early stage of an outbreak in order to implement relevant actions. Early warning of an abortion storm as a result of infection with a notifiable disease, e.g. brucellosis, bovine viral diarrhea (BVD) or infectious bovine rhinotracheitis (IBR), is a significant surveillance tool. This study used data from 507 large Danish dairy herds. A modified two-stage method for detecting an unusual increase in the abortion incidence was applied to the data. An alarm was considered true if an abortion were detected in the month following the alarm month, otherwise false. The total number of abortions that could potentially be avoided if effective action were taken ranged from 769 (22.9%) to 10 (0.3%), as the number of abortions required to set the alarm increased from 1 to 6. The vast majority of abortions could, however, not be predicted, much less prevented, given this early-warning system. The false to true alarm ratio was reduced when the number of abortions that set the alarm increased. The financial scenarios evaluated demonstrated that the value of an abortion, the cost of responding to an alarm and the efficiency of the actions are important for decision making when reporting an alarm. The presented model can readily be extended to other disease problems and multiple-time periods. 相似文献
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996.
Casas E White SN Shackelford SD Wheeler TL Koohmaraie M Bennett GL Smith TP 《Journal of animal science》2007,85(11):2807-2814
The objective of this study was to assess the association of SNP in the thyroglobulin gene, including a previously reported marker in current industry use, with marbling score in beef cattle. Three populations, designated GPE6, GPE7, and GPE8, were studied. The GPE6 population sampled breeds that could be used as alternative germplasm sources in beef cattle production, including Wagyu, Swedish Red and White, Friesian, and Norwegian Red. The GPE7 population sampled 7 popular beef cattle breeds used in temperate climates of the United States: Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental. The GPE8 population sampled Bos indicus-influenced breeds used in subtropical regions of the country and subtropical and tropical regions of the world, including Beefmaster, Bonsmara, Brangus, and Romosinuano. Evaluation of 6 SNP in the thyroglobulin gene, including 5 newly described variations, showed no association (P > 0.10) with marbling score in these populations, except a tendency (P < 0.10) for an association with the previously described marker in GPE6. Closer examination of the GPE6 data revealed that the source of the tendency was an association (P < 0.02) with marbling in animals of Wagyu inheritance. Animals having Wagyu background and inheriting the TT genotype had a greater marbling score (599 +/- 20) than those inheriting the CC (540 +/- 10) or the CT (541 +/- 11) genotype. No association was detected with any other carcass trait for this marker in the 3 populations. Furthermore, none of the 5 newly described markers in the gene displayed an association with marbling score. The data indicate that markers at the thyroglobulin gene may be a useful predictor of marbling performance for producers raising Wagyu-based cattle. Although associations with marbling score in the remaining populations were not large or significant, the TT genotype had the numerically greatest marbling score in each population. 相似文献
997.
The elevated urinary corticoid/creatinine ratios of an 11-year-old Jack Russell terrier with polyuria were suppressible in a high-dose dexamethasone suppression test, which was suggestive of pituitary-dependent hyperadrenocorticism. The absence of physical and routine-laboratory changes compatible with hyperadrenocorticism and the relatively high plasma thyroxine concentration were the impetus for additional studies of thyroid and adrenocortical functions. A high plasma thyroxine concentration (62 nmol/l; 5.0 microg/100 ml) suggested the presence of hyperthyroidism. Radiography, (99m)TcO(4) (-) scintigraphy, ultrasonography, computed tomography and cytology revealed a hyperfunctioning intrathoracic thyroid tumour. In the low-dose dexamethasone suppression test, the plasma cortisol concentration exceeded the reference value of 40 nmol/l (1.4 microg/100 ml) at eight hours after dexamethasone administration (0.01 mg/kg intravenously), a test result compatible with hyperadrenocorticism. In conclusion, this report represents the first case of a dog with an autonomously hyperfunctioning thyroid tumour in the thorax. The elevated urinary corticoid excretion and the positive low-dose dexamethasone suppression test may be explained by alterations in cortisol metabolism, the stress of the hyperthyroid state or both. 相似文献
998.
Burton NJ Comerford EJ Bailey M Pead MJ Owen MR 《The Journal of small animal practice》2007,48(4):220-224
OBJECTIVES: To compare ulnar trochlear notch bone radiopacity in Labrador retrievers with and without fragmented medial coronoid process using quantitative analysis of film density on digitised radiographs. METHODS: Mediolateral view elbow radiographs from Labrador retrievers (n=34) aged between six and 18 months were obtained and digitised. Images from dogs with an arthroscopic diagnosis of fragmentation of the medial coronoid process (n=17) were compared with that of a control population (n=17), and this data subject to statistical analysis. RESULTS: A statistically significant relationship between the presence of increased trochlear notch radiopacity and a fragmented medial coronoid process was identified. Fractional analysis of this area shows the region of greatest difference in radiopacity between normal and fragmented medial coronoid process cohorts to be in the trochlear region of the medial coronoid process of the ulna. A decrease in radiopacity values in the dysplastic group versus the normal cohort was observed for the region of the proximo-caudal ulnar trochlear notch. CLINICAL SIGNIFICANCE: An increase in ulnar trochlear notch radiopacity is a finding associated with fragmentation of the medial coronoid process in Labrador retrievers. 相似文献
999.
OBJECTIVES: To describe the clinical signs, clinicopathological abnormalities and outcome of metaldehyde intoxication in dogs. METHODS: Medical records of dogs presenting between 1989 and 2005 with a diagnosis of metaldehyde toxicity were reviewed retrospectively. Data obtained from the medical record included signalment, history, clinical signs, laboratory tests results, hospitalisation period length, treatments and outcome. RESULTS: Eighteen dogs fulfilled the inclusion criteria. The most prevalent clinical signs were seizures, hyperthermia, tachycardia and muscle tremors. Serum biochemistry abnormalities included increased serum muscle enzymes activities, acidaemia (six dogs) and decreased blood bicarbonate (eight dogs). Treatment was symptomatic and supportive. Hyperbilirubinaemia was observed in two dogs. Diazepam was the most commonly used anticonvulsant followed by phenobarbitone and pentobarbital. General inhalant anaesthesia was required in nine of 18 dogs with seizures unresponsive to anticonvulsants. The survival was 83 per cent (15 of 18 dogs). CLINICAL SIGNIFICANCE: This clinical study recorded, for the first time in the veterinary literature, several clinicopathological abnormalities from severely intoxicated dogs. Metabolic acidosis was common, while acute or delayed hepatotoxicity was an uncommon complication. 相似文献
1000.
Sodium chlorate effectively reduces or eliminates gram-negative pathogenic bacteria in the gastrointestinal tracts of live cattle. Limitations to the in vivo efficacy of chlorate are its rapid absorption from the gastrointestinal tract and its presumed reduction to chloride within the gastrointestinal tract. We hypothesized that chlorate would be reduced via ruminal bacteria in a ruminal in vitro system and that the reduction of chlorate would be influenced by the dietary for-age:concentrate ratio; thus, 4 ruminally cannulated steers were fed 20 or 80% concentrate diets in a crossover design. Ruminal fluid was collected in 2 periods and dispensed into in vitro tubes containing sodium [36Cl]chlorate, which was sufficient for 100 or 300 mg/L final chlorate concentrations. The tubes were incubated for 0, 1, 4, 8, 16, or 24 h; autoclaved, control ruminal fluid, fortified with sodium [36Cl]chlorate, was incubated for 24 h. Chlorate remaining in each sample was measured by liquid scintillation counting after [36Cl]chloride was precipitated with silver nitrate. A preliminary study indicated that chlorite, a possible intermediate in the reduction of chlorate, had a half-life of approximately 4.5 min in freshly collected (live) ruminal fluid; chlorite was, therefore, not specifically measured in ruminal incubations. The chlorate dose did not affect in vitro DM digestion (P > or = 0.11), whereas in vitro DM digestibility was decreased (P < or = 0.05) by 80% forage content. By 24 h, 57.5 +/- 2.6% of the chlorate remained in 100-mg/L incubations, whereas 78.2 +/- 2.6% of the chlorate remained in the 300-mg/L incubations. When the data were expressed on a concentration basis (mg/L), diet had no effect (P > or = 0.18) on chlorate reduction; however, when chlorate reduction was expressed on a percentage basis, chlorate reduction tended to be greater (P > or = 0.09) at 8 and 16 h in the incubations containing the low-concentrate diet. Chlorate remaining in autoclaved controls at 24 h was intermediate (P < 0.01) between chlorate remaining in live ruminal fluid samples incubated for 0 or 24 h. Attempts to isolate chlorate-respiring bacteria from 2 sources of ruminal fluid were not successful. These data indicate that microbial-dependent or chemical-dependent, or both, reduction of chlorate occurs in bovine ruminal fluid and that dietary concentrate had a negligible effect on chlorate reduction. 相似文献