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61.
The spinal cord of 32 psittacines suffering from proventricular dilatation disease (PDD) was investigated. In six cases, a virus was isolated which upon electron microscopic examination revealed morphological details typical of members of the Paramyxoviridae. All isolates were subsequently characterized as avian paramyxovirus serotype 1 (APMV-1) by type-specific polyclonal antisera. According to their reactivity with APMV-1 specific monoclonal antibodies, the six isolates shared epitopes within the haemagglutinin-neuraminidase spike protein, distinct from pigeon-type paramyxoviruses and the LaSota vaccine strain. This grouping was further corroborated by properties of the haemagglutinin: all isolates showed a very thermosensitive haemagglutination activity and were rapid eluters. Virulence of the APMV-1 isolates in 1-day-old specific pathogen free (spf) chicken was very low, with intracerebral pathogenicity indices between 0 and 0.1. In embryonated spf chicken eggs, psittacine isolates replicated to high titres (10(8.6)-10(10.7) EID50/ml). However, they exhibited a reduced lethality over an observation time of 7 days (10(6.1)-10(8.3) ELD50/ml). In a haemagglutination inhibition test with parrot sera from birds with no history of APMV-1 vaccination, sera reacted preferentially with two isolates compared with APMV-1 vaccine strains LaSota and B1. The other four isolates exhibited a differentiated reaction pattern with the parrot sera, indicating an antigenic inhomogeneity. This is the first report of isolating very low virulent APMV-1 from neuronal tissue of parrots and implications for a possible role in slow progressing disease will be discussed.  相似文献   
62.
This study was designed to develop and characterize a swine pneumonic pasteurellosis model by concurrent introduction of Pasteurella multocida type A and Actinobacillus pleuropneumoniae crude cytotoxin. After a series of preliminary experiments, a combination of 4 x 10(9) P. multocida and 4,000 toxic units of A. pleuropneumoniae crude cytotoxin was determined to produce optimal results. A total of 48 pigs were divided into four groups of 12 pigs each. The control group received buffered saline only. Four pigs from each group were randomly selected for necropsy 3, 7 and 14 days postinoculation (PI). Inoculation of pigs with P. multocida and A. pleuropneumoniae cytotoxin (group 1) resulted in moderate to severe pneumonia. Pasteurella multocida was isolated from pneumonic lesions, grossly normal lung, and bronchial lymph nodes of all group 1 pigs throughout the 14 day experimental period. Pathological changes typical of field cases of swine pneumonic pasteurellosis were produced. Pigs inoculated with P. multocida alone (group 2) had pneumonic lesions and P. multocida was reisolated from lungs at three days PI. Pasteurella multocida was not isolated from these pigs at 7 and 14 days PI, except for one pig in which an abscess developed in the thorax. Pulmonary lesions induced by A. pleuropneumoniae crude cytotoxin alone (group 3) were transient and resolved by seven days PI. Group 1 pigs had significantly greater lung lesion volumes than group 2 and 3 pigs at 3, 7 and 14 days PI. Statistical analysis indicated a significant interactive effect of P. multocida and A. pleuropneumoniae cytotoxin on the development of lung lesion volumes at 7 and 14 days PI (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
64.

Objective

Myxomatous mitral valve disease (MMVD) induces progressive left atrial (LA) enlargement. The LA modulates left ventricular filling and performance through its reservoir, conduit, and contractile function. Assessment of LA size and function may provide valuable information on the level of cardiac compensation. Left atrial function in dogs with naturally occurring MMVD remains largely unexplored. The objective of this study was to evaluate LA volume and function in dogs with naturally occurring MMVD.

Animals

This prospective study included 205 client-owned dogs of different breeds, 114 healthy dogs, and 91 dogs with MMVD of different disease severities.

Methods

Using two-dimensional echocardiography, the biplane area-length method was applied to assess LA volume and calculate volumetric indices of LA reservoir, conduit, and contractile function.

Results

Left atrial volume and LA stroke volume increased, whereas LA reservoir and contractile function decreased with increasing disease severity. A maximal LA volume <2.25mL/kg was the optimal cut off identified for excluding congestive heart failure in dogs with chronic MMVD with a sensitivity of 96% and a specificity of 100%. An active LA emptying fraction <24% and/or a LA expansion index <126% were suggestive of congestive heart failure in dogs with chronic MMVD with a sensitivity of 77% and a specificity of 89% and a sensitivity of 82% and a specificity of 82%, respectively.

Conclusion

Dogs with MMVD appear to have larger LA volumes with poorer LA function. Deteriorating LA function, characterized by a decreasing reservoir and active contractile function, was evident in dogs with MMVD with increasing disease severity.  相似文献   
65.
66.
A survey in Burundi, Rwanda, Tanzania and Uganda was conducted in order to determine the different production systems under which Ankole cattle are currently kept. Additionally, selection criteria of livestock keepers were documented. In Burundi, Rwanda and parts of Uganda, livestock keepers are sedentary and herds are small, whereas in the other areas Ankole cattle are kept in large herds, some of them still under a (semi-)nomadic system. Milk is the main product in all areas, and is partly for home consumption and partly for sale. Although the production systems vary in many aspects, the selection criteria for cows are similar. Productive traits such as milk yield, fertility and body size were ranked highly. For bulls, the trait ‘growth’ was ranked highly in all study areas. Phenotypic features (coat colour, horn shape and size) and ancestral information are more important in bulls than in cows. The only adaptive trait mentioned by livestock keepers was disease resistance. In areas of land scarcity (Burundi, Rwanda, western Uganda), a clear trend from pure Ankole cattle towards cross-bred animals can be observed.  相似文献   
67.

Background

Lagotto Romagnolo (LR) dogs with benign juvenile epilepsy syndrome often experience spontaneous remission of seizures. The long‐term outcome in these dogs currently is unknown. In humans, behavioral and psychiatric comorbidities have been reported in pediatric and adult‐onset epilepsies.

Hypothesis/Objectives

The objectives of this study were to investigate possible neurobehavioral comorbidities in LR with a history of benign familial juvenile epilepsy (BFJE) and to assess the occurrence of seizures after the remission of seizures in puppyhood.

Animals

A total of 25 LR with a history of BFJE and 91 control dogs of the same breed.

Methods

Owners of the LR dogs in the BFJE and control groups completed an online questionnaire about each dog''s activity, impulsivity, and inattention. Principal component analysis (PCA) served to extract behavioral factors from the data. We then compared the scores of these factors between the 2 groups in a retrospective case–control study. We also interviewed all dog owners in the BFJE group by telephone to inquire specifically about possible seizures or other neurological problems after remission of seizures as a puppy.

Results

Lagotto Romagnolo dogs with BFJE showed significantly higher scores on the factors Inattention and Excitability/Impulsivity than did the control group (P = .003; P = .021, respectively). Only 1 of the 25 BFJE LR exhibited seizures after remission of epilepsy in puppyhood.

Conclusions and Clinical Importance

Although the long‐term seizure outcome in BFJE LR seems to be good, the dogs exhibit behavioral abnormalities resembling attention deficit hyperactivity disorder (ADHD) in humans, thus suggesting neurobehavioral comorbidities with epilepsy.  相似文献   
68.
Intravascular pulmonary artery sarcomas in combination with myocardial metastasis are rare in dogs. We describe the radiographic, echocardiographic, and electrocardiographic‐gated (ECG‐gated) computed tomographic angiography (CTA) findings in a dog with pulmonary artery sarcoma. All imaging studies demonstrated severe main pulmonary artery enlargement. Echocardiography and ECG‐gated CTA revealed a mass occluding the lumen of the right pulmonary artery. In addition, CTA revealed focal left ventricular myocardial contrast enhancement and parenchymal lung changes. Postmortem examination confirmed the presence of a large thrombus associated with arteriosclerosis and an intravascular sarcoma in the right pulmonary artery with metastases to the myocardium, lungs and brain.  相似文献   
69.
The effects of health classification and of housing and management on performance and meat inspection findings were studied in 166 all-in-all-out finishing herds in Finland in 1995 and 1998. Producers could buy either health-classified (certified free of certain diseases) or standard-class pigs for their farms. Herds that had attained a certain level of housing and management were eligible to join the LSO 2000 management system for finishing herds. In 1995, none of the study herds were LSO 2000 units. In 1998, 76 of them had become LSO 2000 units, while 90 had remained as non-LSO 2000 units. Continuous outcome variables (daily gain and time in the finishing unit) were analysed with a mixed-model procedure with repeated measurements from the same farms. Discrete variables were analysed either with Poisson regression (mortality, whole- and partial-carcass condemnations, organ condemnations, arthritis, abscesses) or logistic regression (liver condemnations, pneumonia, pleuritis). The models were adjusted for the year, size of the herd and the average slaughter weight of the batch.The benefits obtained by the health classification of the feeder pigs included a substantial increase in daily gain (37g, about 5%) and decrease in time in the finishing unit (4 days, about 4%), decrease in mortality (odds ratio, OR 0.68), a substantial decrease in pneumonia (OR 0.37) and pleuritis (OR 0.60), and a substantial decrease in liver (OR 0.45) and organ (OR 0.72) condemnations. Classification of the pigs did not have an effect on the prevalence of whole-carcass condemnations, arthritis or abscesses. The health-classified pigs had, unexpectedly, more partial-carcass condemnations (OR 1.15) than the standard-class pigs. The obtained benefits of the LSO 2000 units were an increase in daily gain (14g, about 2%), decrease in time in the finishing unit (2 days, about 2%), a decrease in mortality (OR 0.69) and a decrease in whole-carcass (OR 0.69) and partial-carcass (OR 0.81) condemnations. The LSO 2000 units did not have any advantage over the non-LSO 2000 units in their prevalence of liver or organ condemnations, arthritis, abscesses, pneumonia or pleuritis.  相似文献   
70.
A growth trial was carried out to test the effect of organic, trivalent chromium and L-carnitine on the body composition of growing rats. At the same time, an evaluation of different measurement methods (weight of epididymal fat pad, adipocyte morphometry, total body electrical conductivity) was performed. Outbred Wistar rats of 30 days of age were fed diets of different (0, 10 and 20%) protein level. The diets were supplemented with 4 mg/kg Cr as chromium nicotinate, and 100 mg/kg L-carnitine. The experimental feeding lasted 15 days, after a 5-day-long adjustment period. It was found that Cr addition increased feed intake. Both treatments caused changes in body composition, increasing fat and protein deposition. Organic chromium had no effect at either protein level, while L-carnitine improved the protein retention only at an optimum (20%) protein supply. No statistically significant correlation was found between total body electrical conductivity (TOBEC) and body composition, which could be attributed to the great individual differences. A close correlation was found among total body fat percentage, weight of epididymal fat pad and the adipocyte surface. The data suggest that there is an interaction between dietary protein supply and the effect of repartitioning agents.  相似文献   
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