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81.
82.
CASE HISTORY: A 5-month-old mixed-breed boar presented with lethargy, weakness and anorexia of 1 week's duration. CLINICAL FINDINGS AND DIAGNOSIS: The boar had an elevated heart rate, slow capillary refill time and cyanotic skin over the ears; it was also severely anaemic. A necropsy revealed scattered petechial haemorrhages, small subcapsular white nodules on the kidneys, a nodule in the parenchyma of one testis, creamy-white bone marrow, a preputial diverticulum, and an ulcer of the pars oesophagea of the stomach. Cytology of peripheral blood and bone marrow identified large numbers of lymphoblasts, which were demonstrated using immunocytochemistry to be of B-cell origin. Histological examination of multiple organs also showed lymphoblastic infiltration. DIAGNOSIS: B-cell lymphoblastic leukaemia with secondary infiltration of lymphoid organs, kidneys, testis and preputial skin. CLINICAL RELEVANCE: This is the fi rst known reported case of acute B-cell lymphoblastic leukaemia in swine.  相似文献   
83.
To determine the Mycoplasma gallisepticum (MG) rapid serum plate agglutination (RSPA) test response of broiler breeders after ts-11 strain vaccination, 55 Cobb pullets derived from a nonvaccinated, MG-negative, commercial, broiler breeder grandparent flock were monitored from 8 to 20 wk of age (over a 12-wk trial period). To evaluate the effect of lateral spread of the ts-11 vaccine strain on RSPA test results from commingled and adjacently penned birds, treatment groups included (A) birds vaccinated with ts-11strain MG at 8 wk of age, (B) commingled nonvaccinates in the same pen as the vaccinated birds, (C) nonvaccinates in a second pen separated from the first pen by a distance of 2 m, and (D) birds vaccinated with ts-11 strain MG at 8 wk of age and kept in a separate room. Rapid serum plate agglutination tests were performed once a week for 6 wk and then every 2 wk for 6 more wk, postvaccination. A polymerase chain reaction (PCR) assay specific fbr ts-11 strain MG was used to confirm vaccination, and a second PCR specific for non-ts-11 strain MG was used to confirm the absence of field infection. Seroconversion was first detected by the RSPA test 2 wk postvaccination and attained maximum positive rates of 58% at 12 wk postvaccination in treatment A and 60% at 8 wk postvaccination in treatment D. Seroconversion rates in nonvaccinated, commingled pullets was 10% at 5 wk and 30% at 12 wk after the vaccination of pen mates. The ts-11-specific PCR detected the vaccine strain in 80%-100% of the vaccinated birds 2 wk after vaccination. One of 15 nonvaccinated birds penned 2 m from vaccinated birds yielded ts-11 by PCR assay 12 wk after vaccination, which indicates that the spread of ts-11 over short distances may be possible in situations in which there is a common caretaker. PCR on tracheal swabs taken 12 wk postvaccination detected ts-l1 in 50% and 60% of the vaccinated birds in treatments A and D, respectively; in 30% of the commingled nonvaccinates; and in 6.6% of the separately penned nonvaccinates. In contrast, choanal swabs collected from vaccinated birds at 12 wk were 21% and 40% PCR positive for ts-11 strain MG, while those from nonvaccinates were negative. All samples were PCR negative for field strain MG. The pattern of seroconversion as measured by RSPA test in small groups of broiler breeders was different from that previously reported for leghorns. Lateral spread of the ts-11 strain to commingled pen mates occurred rapidly, causing RSPA seroconversion patterns that mimicked those of the vaccinated pen mates.  相似文献   
84.
The objectives of this study were to investigate the prevalence of food sensitivity in cats with chronic idiopathic gastrointestinal problems, to identify the food ingredients responsible, and to characterize the clinical features. Seventy cats that presented for chronic gastrointestinal signs underwent diagnostic investigation. Fifty-five cats had idiopathic problems and were entered into the study. Diagnosis of food sensitivity was made by dietary elimination-challenge studies by using commercial selected-protein diets as the elimination diet. Sixteen (29%) of the 55 cats with chronic idiopathic gastrointestinal problems were diagnosed as food sensitive. The clinical signs of another 11 cats (20%) resolved on the elimination diet but did not recur after challenge with their previous diet. The foods or food ingredients responsible for the clinical signs were dietary staples. Fifty percent of affected cats were sensitive to more than 1 food ingredient. The clinical feature most suggestive of food sensitivity was concurrent occurrence of gastrointestinal and dermatological signs. Weight loss occurred in 11 of the affected cats, and large-bowel diarrhea was more common than small-bowel diarrhea. Assay of serum antigen-specific immunoglobulin E (IgE) had limited value as a screening test, and gastroscopic food sensitivity testing was not helpful. In conclusion, adverse reactions to dietary staples were common in this population of cats, and they responded well to selected-protein diets. Diagnosis requires dietary elimination-challenge trials and cannot be made on the basis of clinical signs, routine clinicopathological data, serum antigen-specific IgE assay, gastroscopic food sensitivity testing, or gastrointestinal biopsy.  相似文献   
85.
Background: The quality of histopathology slides of endoscopic biopsies from different laboratories varies, but the effect of biopsy quality on outcome is unknown.
Hypothesis: The ability to demonstrate a histologic lesion in the stomach or duodenum of a dog or cat is affected by the quality of endoscopic biopsy samples submitted. More endoscopic samples are needed to find a lesion in poor-quality tissue specimens.
Animals: Tissues from 99 dogs and 51 cats were examined as clinical cases at 8 veterinary institutions or practices in 5 countries.
Methods: Histopathology slides from sequential cases that underwent endoscopic biopsy were submitted by participating institutions. Quality of the histologic section of tissue (inadequate, marginal, adequate), type of lesion (lymphangiectasia, crypt lesion, villus blunting, cellular infiltrate), and severity of lesion (normal, mild, moderate, severe) were determined. Sensitivity of different quality tissue samples for finding different lesions was determined.
Results: Fewer samples were required from dogs for diagnosis as the quality of the sample improved from inadequate to marginal to adequate. Duodenal lesions in cats displayed the same trend except for moderate duodenal infiltrates for which quality of tissue sample made no difference. Gastric lesions in dogs and mild gastric lesions in cats had the same trend, whereas the number of tissue samples needed to diagnose moderately severe gastric lesions in cats was not affected by the quality of tissue sample.
Conclusions and Clinical Importance: The quality of endoscopically obtained tissue samples has a profound effect on their sensitivity for identifying certain lesions, and there are differences between biopsies of canine and feline tissues.  相似文献   
86.
87.
In the case of high valuable individuals with very precious genetic material, widening the genetic pool including gametes with poor morphological characteristics, as cumulus‐denuded oocytes (CDOs), could be an option. To improve the in vitro culture of low‐competence feline CDOs, an enriched three‐dimensional (3D) system in association with competent cumulus–oocyte complexes (COCs) was developed. For this purpose, domestic cat CDOs were cultured with or without companion COCs in the 3D barium alginate microcapsules. The overall viability and the meiotic progression of feline CDOs cocultured with COCs or cultured separately in 3D or in 2D (traditional microdrops) system were compared. The 3D system was able to support viability and meiotic resumption of the feline oocytes, as well as the 2D microdrops. In 3D microcapsules, the presence of COCs resulted in a higher viability of CDOs (91.1%, < .05), than that obtained without COCs or in 2D microdrops (71.2% and 67.3%, respectively), but the percentages of meiotic resumption were similar of those of CDOs cultured separately (55.4% vs. 40.4%, p > .05). It is notable that the presence of CDOs seemed to enhance the meiotic progression of the associated COCs. In conclusion, the 3D barium alginate microcapsules are a suitable system for feline oocytes in vitro culture, but more specific enriched conditions should be developed to improve the CDOs full competence in vitro.  相似文献   
88.
Antioxidants have been widely used during in vitro production to decrease the negative effect of reactive oxygen species. It was reported that the complex resveratrol–methyl β‐cyclodextrin (RV ‐CD ) improves resveratrol's stability and bioavailability and increases its antioxidant activity. This study evaluates the effect of RV ‐CD during in vitro oocyte maturation (IVM ) or in vitro embryo culture (IVC ) on developmental competence and quantitative changes in gene expression of developmental important genes. In experiment 1, RV ‐CD was added to IVM media and maturation level, embryo development and oocytes, cumulus cells, and blastocysts gene expression by RT ‐qPCR were examined. In experiment 2, presumptive zygotes were cultured in SOF supplemented with RV ‐CD and embryo development and blastocysts gene expression by RT ‐qPCR were studied. A group without RV ‐CD (control?) and a group with cyclodextrin (control+) were included. No differences were found in cleavage rate or blastocyst yield between groups. However, the expression of LIPE was higher in blastocysts derived from oocytes treated with resveratrol compared with control groups (<  .05). Blastocysts produced by IVC with resveratrol showed that RV ‐CD could modify the expression of genes related to lipid metabolism (CYP 51A1 , PNPLA 2 and MTORC 1 ) compared with control groups (p  < .05). RV ‐CD in the IVM and IVC media could reduce accumulated fat by increasing lipolysis and suppressing lipogenesis of blastocysts.  相似文献   
89.
90.
Gastritis, vomition and weight loss are common in captive cheetahs (Acinonyx jubatus). Gastric spiral bacteria (Helicobacter spp.) and the very small, viviparous nematode Ollulanus tricuspis, a stomach worm of cats, are believed to be important causes. Three sibling cheetahs at Wellington Zoo, New Zealand, developed chronic vomiting, diarrhoea and debility. Their parents were both South African-born. Response to antibacterial treatment was poor. Endoscopic examinations revealed chronic lymphoplasmacytic gastritis and Ollulanus infection. Treatment with oxfendazole and pyrantel embonate resulted in clinical improvement; however, 1 cheetah, which died 7 months later as a result of a ruptured liver due to hepatic amyloidosis, still had Ollulanus worms present in her stomach. Ollulanus tricuspis is a significant cause of gastritis and vomiting in captive cheetahs, lions and tigers, as well as wild cougars and tigers. The parasite has not yet been found in sub-Saharan Africa. Because of the unusual characteristics of this parasite, the literature on its life history and techniques for diagnosis is reviewed.  相似文献   
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