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41.
The morphologic and pathologic changes which occurred within the cecal mucosa of 4 horses during the onset of laminitis were determined from cecal biopsy materials obtained via a cecal fistula; the laminitis was induced with carbohydrate overload. The cecal epithelial mucosa specimens were obtained at 0 (base line), 24, 32, 48, and 72 hours after horses were given carbohydrate overload, and these were fixed and subsequently photographed. Changes in the cecal epithelium were examined by transmission electron and scanning electron microscopies. These histopathologic changes indicated that the mucosal barrier was substantially damaged by the carbohydrate overload.  相似文献   
42.
This paper describes the causes of death of 54 maras (Dolichotis patagonum) in a captive colony in Mexico over a period of seven years. There were 35 adults, 11 juveniles, five neonates, two fetuses and one stillbirth--27 males, 21 females and six whose sex was not determined. Trauma was the cause of 25 deaths, and there were eight cases of fatal bacterial infection. Besnoitiosis was the only parasitic disease found frequently (13 cases), and was associated with fatal interstitial pneumonia in three juveniles. Right-sided hypertrophic cardiomyopathy attributed to high altitude was observed in 26 maras, and in three cases death was attributed to acute cardiac dysfunction. Two maras died of disseminated histoplasmosis and two of hyperthermia. Additional causes of death included one case each of uterine torsion, intestinal intussusception, aspiration pneumonia and hydranencephaly. Gastric erosions with luminal haemorrhage were found in 27 of the maras and splenic lymphoid depletion in 20, changes that were attributed to stress.  相似文献   
43.
An approximately 31-yr-old California sea lion (Zalophus californianus) with a history of chronic visual impairment and corneal disease presented with slow onset, progressive neurologic deficits. Treatment for rear flipper paresis was not effective and the animal was euthanatized. Histopathologic findings included hepatocellular and biliary neoplasia, ocular amyloidosis, adrenal adenoma and pheochromocytoma, and spinal cord changes consistent with multicentric neurofibromatosis. This is the first documentation of these conditions in a California sea lion.  相似文献   
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In this work, we evaluated whether embryo development and pregnancy rates would be affected by culturing bovine Bos indicus embryos in Synthetic Oviductal Fluid with amino acids (SOFaa) or G1/G2 sequential medium under a low‐oxygen atmosphere. Using Ovum Pick Up, we obtained 1,538 oocytes, divided into G1/G2 (n = 783) and SOFaa (n = 755). No difference was observed for blastocyst development among the groups (27.8% ± 14.6 and 34.9% ± 20.0 for G1/G2 and SOFaa respectively, p > 0.05). Transferring the embryos (n = 450) from both groups to recipients resulted in similar pregnancy rates for the G1/G2 (38.4% n = 78/203) compared to the SOFaa (39.7% n = 98/247). Our findings confirm that Bos indicus embryos cultured in SOFaa and G1/G2 under low‐oxygen atmosphere have similar in vitro (blastocyst rate) and in vivo (pregnancy rate) developmental capacity. However, embryos cultured in G1/G2 medium have higher cleavage than those cultured in SOFaa medium.  相似文献   
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A 4‐year‐old, spayed female French Bulldog was presented for respiratory distress and suspected aspiration pneumonia after oral administration of activated charcoal for possible ingestion of a suspected toxic dose of trazodone. The patient had a moderate volume of pleural effusion, which contained free and intracellular black particulate matter consistent with charcoal. Due to presumed charcoal aspiration with subsequent lung rupture, the right middle and right caudal lung lobes were surgically removed. Histology revealed abundant black debris consistent with charcoal and severe granulomatous inflammation. Based on the clinical, gross, and histologic findings, a diagnosis of severe, chronic, locally extensive, aspiration pneumonia and lung rupture with secondary pleuritis and mediastinitis due to charcoal aspiration was made. Aspiration pneumonia is the main complication of activated charcoal administration, which can incite extensive, granulomatous inflammation in the respiratory tract. To the authors’ knowledge, this is the first report describing the cytologic and histologic findings associated with inadvertent charcoal aspiration in a veterinary species.  相似文献   
48.
A neonatal male sable antelope (Hippotragus niger) was found dead. A 5 by 12-cm lobulated mass was present in the oral cavity, attached to the caudal border of the soft palate; this mass contained hair, cartilage, bone, nervous tissue, muscle, and multiple gland-like structures. Histopathologic diagnosis was consistent with oropharyngeal teratoma. As a result of the lack of wear of the fetal hooves, the firm, collapsed appearance of the lungs, and the lack of other gross or histopathologic abnormalities, the oropharyngeal tumor is suspected to have caused an airway obstruction, resulting in the calf's early postnatal death. This is the first report of an oropharyngeal teratoma in the veterinary literature.  相似文献   
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Members of the genus Acanthamoeba are usually free-living amebae and are found in a variety of ecological niches including soil, fresh and brackish water, dust in air, filters of heating, ventilating, and air conditioning units, swimming pools and hot tubs, etc. Occasionally, they are also known to cause central nervous system infections in humans and other animals. We isolated into culture an amoeba from the liver tissue of a keel-billed toucan and identified it as Acanthamoeba sp. based on culture characteristics and immunofluorescent analysis. Further, we characterized the cultured amoeba and also the amoeba in the liver tissue as Acanthamoeba, genotype T4, by sequencing a diagnostic region of the nuclear small subunit ribosomal RNA gene.  相似文献   
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