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931.
Clinical, parasitological and biochemical parameters were evaluated in Corriedale and Crioula Lanada sheep after a single experimental infection with Haemonchus contortus. Ten 4-month-old worm-free lambs, of each breed, were infected with 200 L3 H. contortus per kg live weight and four uninfected animals of each breed were used as controls. Every week, the animals were weighed and blood and faecal samples were collected for measurement of packed cell volume (PCV), total serum protein (TSP) and albumin (ALB), and the number of eggs per gram of faeces (EPG), respectively. Twelve weeks after infection, the animals were slaughtered. The worm burden was determined and samples of the abomasal mucosa were processed for determination of the number of eosinophils, mast cells and globule leukocytes. No significant differences in PCV, TSP, ALB, parasite burden or the cell populations of the abomasal mucosa were observed between breeds, but Crioula lambs had a lower EPG count. The comparison of the infected groups with their respective controls revealed significant alterations in PCV, TSP and ALB in the Corriedale lambs and in PCV, TSP, ALB and the density of eosinophils and mast cells in the Crioula lambs.  相似文献   
932.
Detection of antibodies against peste des petits ruminants virus in sera of cattle, camels, sheep and goats in Sudan.  相似文献   
933.
In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El-Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme-linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV-specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled.  相似文献   
934.
The study describes three polymerase chain reaction (PCR) systems for the CVI988 vaccine virus: the meq gene, the MDV BamHI-D/H 132 bp tandem repeat fragment and the MDV-gB gene. Whereas the PCR product of virulent MDV strains and of the CVI988 virus strain with the meq and the 132 bp primer sets differed for the two templates, the MDV-gB PCR products were similar. The sensitivity of the three PCRs was determined for the two templates: the CVI988 DNA was detected up to 2.48 plaque forming units, and a MDV-1 DNA, was amplified with the 132 bp primers up to the 10(-3) DNA dilution, and up to the 10(-2) with the MDV-gB and meq gene primers. As conventional detection for the CVI988 vaccine virus is by tissue culture, the aim was to analyse the feasibility of the molecular detection of the vaccine virus in the vaccinated chick. In two experimental trials employing specific pathogen free and commercial Lohmann chicks, respectively, the vaccine virus replicated to a limited extent; it was detected only in the spleen of up to 60% chicks at 2-4 weeks and in one chick at 3 weeks, respectively. The survey of three commercial Lohmann flocks, kept in biosecurity conditions, revealed the vaccine virus only in the spleen of 40% of 30-day-old chicks. The present study shows that CV1988 DNA is present in vaccinated chicks in a low quantity and it is difficult to detect directly from the chick, probably because vaccine viruses are latent in vivo. For an efficient detection it is pertinent to cultivate the vaccine virus on chicken embryo fibroblasts (CEF), as then the virus escapes the latent state, enters into the productive mode of replication, and a high viral copy number is produced.  相似文献   
935.
In this study the clinico-pathological aspects of cutaneous and mucocutaneous plasmacytomas were investigated in 63 dogs (one dog with two tumours). The tumours were most commonly observed in the skin of the trunk and legs. Yorkshire Terrier (n = 8) was the most commonly affected breed and males were affected more commonly than females (36 versus 23, respectively). Plasmacytomas were histologically classified into mature, hyaline, cleaved, asynchronous, monomorphous blastic and polymorphous blastic cell types. Monomorphous blastic cell type was the most frequent type (n = 21), followed by cleaved (n = 19) and asynchronous (n = 11) cell types. Secondary amyloid depositions were observed in eight cases. Immunohistochemical staining showed monoclonal lambda light chain positivity in all cases. In the immunohistochemical staining for cyclin D1, which is a prognostic marker in human plasma cell tumours, moderate numbers of positive tumour cells were observed in only one case of (muco)cutaneous plasmacytoma. All other cases were negative or contained few positive tumour cells. On the other hand, high numbers of tumorous plasma cells reacted positively with cyclin D1 in three out of six cases of canine multiple myelomas. Prognosis of the (muco)cutaneous plasmacytomas was good, except in one dog which developed a lymphoma afterwards. No significant correlations were observed between the cell type and the location of the tumour, presence of amyloid or prognosis.  相似文献   
936.
This experiment was carried out to determine the effect of short-term hypothermia on blood malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glucose-6-phosphate dehydrogenase (G-6-PD) concentrations in rats. Twenty Sprague-Dawley rats were used weighing 180-200 g and on average 3.5 months old. They were randomly divided into two experimental groups: control (without cooling) and hypothermic (with cooling). The rats of the hypothermic group were cooled by immersion into cold water (10-12 degrees C), and the control rats were immersed into water of body temperature (37 degrees C) up to the neck without using any anaesthetic or tranquilizer for 3 min Rectal body temperatures of both groups were measured and blood samples to analyse MDA, GSH, SOD, GSH, GSH-Px and G-6-PD were collected immediately after the treatment. It was found that the MDA level was higher and the GSH and G-6-PD levels were lower in the hypothermic group than those in the controls. There was no difference between the control or hypothermic group regarding SOD or GSH-Px levels. It is concluded that acute hypothermia increased the lipid peroxidation and decreased the GSH and G-6-PD levels in rats.  相似文献   
937.
A total of 19 adult hill cattle of both sexes were subjected to trans-rectal ultrasound scanning of urinary bladder to evaluate bladder wall thickness and the presence of space-occupying lesions. The animals were divided into four groups. Eight apparently healthy hill cattle maintained under standard ration served as control (group I) and the remaining II animals were divided into three groups (II, III and IV). Group II animals (n = 8) were fed with different type of ferns which were further divided into subgroups II-P, -D and -B and fed with Polystichum squarrosom (n = 2). Dryopteris juxtaposita (n = 2) and Pteridium aquilinum (n = 4) ferns, respectively. The one animal in group III was a natural case of enzootic bovine haematuria (EBH) and the two animals in group IV were natural cases of microscopic EBH fed with Polystichum squarrosum fern. In group I animals, the average bladder wall thickness was 1.45 mm. The delineation of the bladder wall was uniformly smooth and the echo pattern of the bladder was homogeneously black, which was suggestive of clear urine content. In group II (P, D and B) the average bladder wall thickness of the six animals was 1.87 mm and the sonographic features were within normal limit when compared with controls. In two of the animals of group II-B, the bladder wall was apparently thick (4.36 mm) and there was no intraluminal mass except at one or two focal elevated points. Animals of groups III and IV showed the average bladder wall thickness of 4.86 mm and were characterized by the presence of irregular sessile masses extending into the bladder lumen. The homogeneous anechoic area was reduced centrally due to the presence of a hypoechoic soft tissue mass all around the bladder wall. Post-sonographic urinalysis, biopsy and necropsy of selected cases further confirmed the sonographic findings.  相似文献   
938.
Delayed acute capture myopathy is the term used to describe the clinical syndrome observed in three roe deer captured by drive-nets and transported to an enclosure for scientific purposes. The animals died 48 h, 60 h and 8 days after being captured. The simultaneous deaths coincided with a previous episode of deliberate human disturbance. The histopathological findings were indicative of acute myopathy and myoglobinaemic nephrosis. These could be related to an ataxic myoglobinuric syndrome brought on by capture and transport operations. The lack of clinical signs and negative prognosis indicators in the period between capture and just before death. the absence of gross muscular lesions in the animal that died after 8 days post-capture, the simultaneous deaths of animals captured at different times and the evidence of deliberate human disturbance in the enclosure are suggestive of death triggered by a second stress episode.  相似文献   
939.
In the following, we describe the isolation and sequencing of the equine surfactant protein A (Sp-A) as found in both the cDNA and the genomic DNA. We found a length of the cDNA sequence of 747 bp (base pairs), in translation into amino acids of 248. Compared with the known molecular biological facts about Sp-A in other species, the cDNA sequence obtained showed highest homology with that of sheep (85.01%). The genomic DNA of equine Sp-A, as in other species, includes three introns. There were no hints for the existence of two different Sp-A genes. These results should form the basis for a better understanding of respiratory failure in foals and adult horses, and also lead to further studies on this item.  相似文献   
940.
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