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991.
We aimed to investigate the ratio of accompanying diseases in cows suffering from clinical hypocalcaemia and their influence on cure rate. In five veterinary practices in different regions of Germany, all recumbent cows around parturition were included in the study for a period of 1 year. After recording the case history a clinical examination was done and a serum sample was taken to measure the concentrations of calcium and phosphorus magnesium, beta-hydroxybutyrate, total bilirubin, cholesterol, urea, and the activities of ASAT, CK, and GLDH. Only cows with hypocalcaemia entered the statistical analysis. Hypocalcaemia was the major cause of recumbency in cows of the second lactation or elder. Muscle damage was the second frequent diagnose in recumbent cows and the major concomitant disease in hypocalcaemic cows. The overall cure rate was between 89.4% and 94.8%. Calcium and phosphorus concentrations did not have an influence on cure rate. Non-cured cows had higher serum activities of CK (p<0.043) and ASAT (p<0.006). Nevertheless, the activities of CK and ASAT were no good predictors of treatment failure because of their low specificity and the high cure rate of the cows in the five practices.  相似文献   
992.
The incidence of canine rabies has been widely reported in Brazil, and new rabies virus (RV) variants, genetically similar to canine RV, have recently been isolated from foxes. In order to derive the epidemiological characteristics of Brazilian Carnivora RV, Brazilian RVs isolated from dogs, cats, and foxes were genetically analyzed. Brazilian Carnivora RV isolates were divided into 2 main lineages. The predominant lineage was found in dogs and cats, which included the Argentinean and Bolivian Carnivora RV isolates, and was extensively distributed throughout Brazil and surrounding countries. The other lineage consisted of three sublineages containing Brazilian dog and fox RV isolates, with the dog sublineages located on an internal branch of 2 fox sublineages, suggesting that RV transmission events might have occurred between foxes and dogs in the past. These results suggest that contact between dogs and wildlife has the potential to generate new rabies variants and that it is important to control RV infection cycles in both dogs and wildlife to prevent spread of rabies infection.  相似文献   
993.
A dynamic optimization model was developed and used to evaluate alternative foot-and-mouth disease (FMD) control strategies. The model chose daily control strategies of depopulation and vaccination that minimized total regional cost for the entire epidemic duration, given disease dynamics and resource constraints. The disease dynamics and the impacts of control strategies on these dynamics were characterized in a set of difference equations; effects of movement restrictions on the disease dynamics were also considered. The model was applied to a three-county region in the Central Valley of California; the epidemic relationships were parameterized and validated using the information obtained from an FMD simulation model developed for the same region. The optimization model enables more efficient searches for desirable control strategies by considering all strategies simultaneously, providing the simulation model with optimization results to direct it in generating detailed predictions of potential FMD outbreaks.  相似文献   
994.
In Burkina Faso, we assessed the efficacy of treating cattle with a footbath containing aqueous formulations of pyrethroids to control two tsetse-fly species, Glossina tachinoides Westwood, 1850 (Diptera, Glossinidae) and Glossina palpalis gambiensis Vanderplank 1949. Legs were the most targeted parts of the body for tsetse-fly blood meals: 81% (95% CI: 73, 89) for G. tachinoides and 88% (81, 95) for G. palpalis.

The in-stable efficacy of footbath treatments was compared with manual full spraying with a 0.005% alphacypermethrin (Dominex, FMC, Philadelphia, USA) formulation (250 mL versus 2 L). The proportions of knocked-down flies were the same with footbath and full spray but the latter was more protective against fly bites. In field use, the efficacy of both methods should be similar given the recommended treatment frequency: 3 days for footbath versus 7 days for full spray.

Among 96 cattle drinking at the same water point in Dafinso (Burkina Faso), 68 (71%) were treated with a footbath containing a 0.005% deltamethrin formulation (Vectocid, CEVA SA, Libourne, France). We observed the effect of this live-bait technique on the one hand on released cohorts of reared, irradiated flies, and on the other hand on wild tsetse flies. In both cases, the footbath treatment was associated with a reduction of the apparent fly density probably related to an increased mortality.  相似文献   

995.
996.
The effects of increasing fetal numbers and their distribution between the left and right uterine horns on calf survival, calf BW at birth and weaning, gestation length, dystocia, and calf sex ratio were evaluated for single (n = 1,587), twin (n = 2,440), and triplet calves (n = 147) born to primiparous and multiparous females in the Twinner population at the US Meat Animal Research Center between 1994 and 2004. Cattle were distributed equally between the spring and fall breeding seasons. Fetal number and distribution in utero were determined by real-time ultrasonography at 40 to 70 d postbreeding. For cows and heifers combined, number of calves per parturition increased from 1.34 in 1994 to 1.56 in 2004. Gestation length was 6.8 d shorter (P < 0.01) for twins compared with singles (277.5 +/- 0.2 vs. 284.3 +/- 0.2 d) and 12.7 d shorter for triplets (271.6 +/- 0.8 d). Survival and BW of individual calves at birth decreased (P < 0.01) but total calf BW per dam increased (P < 0.01) as fetal number increased from single to triplet births. Twins resulting from bilateral twin ovulations had increased (P < 0.01) survival and BW at birth, a longer (P < 0.01) gestation length, and less (P < 0.01) dystocia than twins resulting from unilateral twin ovulations. Calf survival and BW at birth were 97.2 +/- 0.3% and 48.0 +/- 0.1 kg for singles, 92.0 +/- 0.4% and 39.0 +/- 0.2 kg for bilateral twins, 83.2 +/- 0.4% and 36.7 +/- 0.2 kg for unilateral twins, 73.8 +/- 1.4% and 30.6 +/- 0.7 kg for bilateral triplets, and 51.9 +/- 3.2% and 31.7 +/- 1.6 kg for unilateral triplets. Birth weight of single calves increased by 0.51 kg/d for each additional day of gestation length vs. 0.38 kg/d for individual twins. Calf BW at birth increased (P < 0.01) with age of dam from 2 to 4 yr. Twin and triplet births had a greater (P < 0.01) incidence of dystocia than single births. The ratio of male:female calves (0.52:0.48) at birth was not affected by type of birth. Postnatal calf survival was similar for all 3 types of birth. Total progeny BW at weaning for single, twin, and triplet births was 217.7 +/- 2.5, 328.3 +/- 3.2, and 378.4 +/- 15.0 kg, respectively (P < 0.01). Although most bovine females have the uterine capacity to gestate twin calves, decreased survival and BW of unilateral twins and of all triplets indicate that their growth and development may have been compromised by uterine crowding.  相似文献   
997.
Pseudogout, the acute form of calcium pyrophosphate deposition disease, is a common condition in elderly human beings and is characterised by the sudden onset of intense joint pain and synovitis. It is rarely identified in animals but was diagnosed in two dogs that presented with acute lameness and pyrexia. Cytology of the synovial fluid showed a mildly elevated cell count with both non-degenerate neutrophils and mononuclear cells present. Many of the mononuclear cells and occasional neutrophils contained square or rhomboid-shaped crystals that were variable in shape and size and weakly birefringent on examination under polarised light. Clinical signs resolved following treatment with prednisolone.  相似文献   
998.
An 11-year-old, female, spayed cocker spaniel was presented with dysphonia caused by a solitary laryngeal mass. Excisional biopsy was performed, and a diagnosis of plasmacytoma was made on the basis of histological examination. Further investigations showed no signs of systemic involvement. Coarse fractionated radiation therapy failed to control the tumour. Therapy was successfully instituted with a conventional combination chemotherapy protocol over a period of 14 months. The dog remains disease free 30 months after diagnosis. Most solitary, extramedullary plasmacytomas in dogs arise in the gastrointestinal tract, with fewer reports in other sites. The larynx is an uncommon sight of involvement in any species, and to the authors' knowledge, this is the first report of this tumour type in the canine larynx. In contrast to the therapeutic benefits reported in humans, the combination of surgery and radiation therapy was unsuccessful in this case, although sustained remission was gained following chemotherapy.  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.
Spirocerca lupi is a nematode mainly affecting dogs but has been found in other animals, particularly carnivores. Anatomical areas of typical and aberrant migration vary. This report describes four cases of Spirocerca lupi causing neurological symptoms, similar to thoracolumbar disc syndrome, as a result of aberrant migration of the nematode into the spinal canal. In two of the cases, the nematode could be demonstrated intraoperatively. The third was discovered on post-mortem examination, while the fourth case displayed compelling evidence of Spirocerca lupi involvement. Surgical removal of the Spirocerca lupi nematode would be the treatment of choice in cases of spinal migration, with therapeutic and preventive treatment with doramectin instituted to treat remote sites and prevent re-infection. In areas endemic for spirocercosis, Spirocerca lupi should be considered as an important differential diagnosis in cases that are presented with clinical signs suggestive of a spinal cord lesion.  相似文献   
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