Asceptic necrosis of bone in a dog

Necrosis of intramedullary bone and bone marrow elements is reported in the long bones of a dog. Radiographically lesions were evident as an irregular increase in intramedullary density. On gross postmortem examination necrotic tissue appeared as yellow-white deposits on the endosteal surface and in the medullary cavity. Microscopically, necrotic bone had empty lacunae and was often covered by basophilic, woven bone. The cause and pathogenesisof aseptic necrosis of bone are discussed.     

鹅巴氏杆菌病的病原分离鉴定及其病理学观察

通过镜检、培养、琼扩试验、生化鉴定及动物回归等试验,从临床表现为神经症状、眼观主要病变为肝肿大、肝表面和切面有灰白色坏死灶为主要特征的病鹅体内分离出禽多杀性巴氏杆菌,其主要病理组织学变化为部分肝小叶内含有一个或多个凝固性坏死灶;大脑皮层血管周围有多量的中性粒细胞浸润,形成明显"血管套"现象,呈化脓性脑炎变化.通过电镜观察、SPF鸡胚接种和血凝抑制试验等排除了禽流感、新城疫等病毒感染的可能性,为禽巴氏杆菌病的诊断提供了资料.     

Fatal winter dysentery with severe anemia in an adult cow

An adult dairy cow fatally affected with winter dysentery was investigated pathologically and virologically. The cow had severe anemia and diarrhea with massive blood. Pathologically, the loss of surface epithelial cells and necrosis of crypt epithelial cells in the large intestine were observed. Bovine coronavirus (BCV) antigen was observed in necrotic crypt epithelial cells of the large intestine. Virus particles were found in the necrotic epithelial cells of the large intestine. Virologically, BCV was isolated from the feces of the dead cow. The dead cow had no serum antibody against BCV although the co-habitants did. These suggest that severe infection of BCV in the cow without the BCV antibody accompanied by severe hemorrhagic anemia resulted in the cow's death.     

Feline cutaneous and visceral necrotizing panniculitis and steatitis associated with a pancreatic tumour

The association of pancreatic disorders with fat necrosis in domestic animals is rare. This report concerns a case of cutaneous/subcutaneous necrotizing panniculitis and steatitis associated with a pancreatic adenocarcinoma in an 11-year-old male Siamese cat. Clinical investigation revealed variably sized nodules on the trunk, limbs and abdomen. Some of them were ulcerated; others showed a shiny yellow necrotic background featuring irregular sinus tracts. The cat was euthanized at the owner's request before a diagnosis could be made. At necropsy, abundant oily material resembling mustard replaced the subcutaneous tissue and small yellow nodules were disseminated in the omentum, mesentery and serosa of the abdomen. A multilobulated mass arising from the anterior pancreatic head was found along with liver and lymph node metastasis. Histopathology showed wide fistulous tracts draining necrotic fat from the subcutis toward the surface and multifocal areas of necrotic adipocytes replacing the panniculus. Duct-like structures and tubules lined by neoplastic epithelial cells were observed in the primary pancreatic tumour and in the metastatic sites. The aetiology of the fat necrosis was possibly the result of systemic release of lipolytic pancreatic enzymes.     

猪弓形虫病诊断及临床病理学研究

对一起猪病进行了流行病学调查和临床病理学研究，同时结合血清学和PCR检测，结果表明，该起猪病是由弓形虫感染引起。临床症状：高热稽留，呼吸困难，体表发紫，先便秘后腹泻，共济失调，最后衰竭而死亡；病理变化特征：肺水肿、间质性肺炎，坏死性脾炎，局灶性坏死性肝炎和淋巴结炎，非化脓性脑炎以及间质性肾炎等。     

Interactions between the membranes of turkey cells and Mycoplasma meleagridis

We used Myoplsma meleagridis (MM) to infect the RP-9 cells and the eggshell membranes and scanning electron microscopy (SEM) and confocal microscopy to study the interactions between the organisms and the cell surfaces. The surface of the RP-9 cells contained numerous projections. After 24 hr of infection with MM, those projections were either lost or aggregated to the side; MM-like particles could be seen on the surface of the cells, and surface fluorescence could be detected by confocal microscopy. On the surface of MM-infected shell membranes were necrotic fibrous tissues and cells detected by SEM and an intense surface fluorescence detected by confocal microscopy. These results indicate that MM infection of the cell surface can result in cellular damage.     

Dysentery in pigs associated with cystic enlargement of submucosal glands in the large intestine.

Grossly visible glands were found in the submucosa of the large intestine of five pigs with dysentery. Some were cystic, some were filled with necrotic debris and some had perforated the serosal surface. The mucosa of the large intestine of all pigs had areas of acute catarrhal inflammation with haemorrhage and focal sloughing of the surface epithelium. Although very distinctive and analogous in most respects to collitis cystica profunda, it was felt that the cystic and hypertrophic glands were a secondary finding and represented involvement of glandular elements present in normal animals. Anaerobic vibrio were recovered from three pigs, but the significance of these isolates is unknown.     

Products to alleviate the effects of necrotic enteritis and aflatoxin on growth performance,lesion scores,and mortality in young broilers

This study investigated the effects of necrotic enteritis challenge or a necrotic enteritis challenge with an additional challenge from dietary aflatoxin B₁ compared to broilers that were unchallenged. Also tested were products designed to help alleviate those effects. Lesion scores were higher in broilers challenged to induce necrotic enteritis, but this did not increase with added aflatoxin. The presence of dietary aflatoxin during a necrotic enteritis challenge significantly increased the negative effects of the necrotic enteritis challenge. During the necrotic enteritis challenge virginiamycin, Calibrin-Z, or a blend of Calibrin-Z, an organic acid, and yucca, helped to decrease the effects of the challenge. When birds are challenged with necrotic enteritis and dietary aflatoxin is present, Calibrin-Z had an advantage over all other tested products.     

Normal Postpartum Involution of the Uterus in the Dog

Ninety-eight reproductive tracts from dogs at different postpartum time periods were used to investigate stages of normal involution. Seventy-eight reproductive tracts were obtained from the field, and 20 obtained surgically for gross and microscopic examination. Plasma progesterone was measured in 22 dogs at various times postpartum.

The uterine horns during the first week postpartum were dilated and edematous. The placental sites were 1.5-3 cm in width, rough, granular and covered with mucus and a few blood clots. By the fourth week the placental sites were thick, grayish-tan and nodular with a few blood clots within nodules. The uterine horns during the seventh week were greatly contracted and the placental sites were narrow and light in color. A few nodules were still present on the surface. By the ninth week the uterine horns were uniform in shape and contracted with a narrow lumen. The placental sites appeared as a narrow brown band.

Histologically the placental sites during the first week postpartum were covered by an eosinophilic staining necrotic mass and a few intact epithelial cells scattered on the surface as an interrupted single layer. Under the necrotic mass, large eosinophilic staining cells in moderate number were scattered throughout the lamina propria of the placental site. These cells were considered to be decidual cells. By the fourth week the placental sites were covered by a large lobulated mass of collagen fibers. The uterine glands were greatly dilated and degenerate, and mononuclear cell infiltration in the lamina propria was pronounced. By the seventh week, large masses of collagen fibers were detached from the surface, and endometrial glands were normal in size and shape. By the ninth week surface sloughing was completed. However, regeneration and replacement of the endometrial lining from the mouth of the uterine glands continued until the end of the twelfth week when the involution process was completed.

The progesterone levels were very low for eight weeks postpartum.

     

Experimental Brucella abortus induced abortion in a llama: pathologic effects

Brucella abortus infection has not been documented in llamas. This report describes the abortion of the only pregnant animal in a group of 12. The llama was infected by inoculating 1 x 10(8) viable B. abortus organisms into the conjunctival sac. Forty-three days postinfection, the llama aborted a fetus of approximately 8 months gestational age. Brucella organisms were isolated from the placenta and all fetal specimens examined. These organisms were also isolated from the dam's mammary gland and numerous lymph nodes when the llama was necropsied 42 days later. Microscopically, there was a moderate, multifocal, lymphocytic and histiocytic, subacute placentitis with marked loss of trophoblastic epithelial cells. The superficial chorioallantoic stroma contained abundant necrotic and mineralized debris as well as numerous swollen capillaries protruding multifocally from the denuded surface. Immunohistochemistry revealed that these capillaries, as well as sloughed and intact trophoblasts, were expanded by large numbers of Brucella organisms. Brucellar antigen was also detected in occasional macrophages in the fetal kidney and lung. Ultrastructurally, bacteria labeled by an antibody-based colloidal gold procedure were located within degenerate capillaries, within necrotic leukocytes, and extracellularly in the placental stroma.     

Sandwich ELISA detection of Clostridium perfringens cells and alpha-toxin from field cases of necrotic enteritis of poultry

Sandwich ELISAs (sELISAs) for the detection of Clostridium perfringens cells and alpha-toxin were developed and used to screen intestinal samples from normal broiler chickens and from clinical cases of necrotic enteritis. The assays clearly distinguished between the two sets of samples. The sELISA absorbance values from samples obtained from the majority of healthy birds were low and those from the majority of necrotic enteritis cases were high. Together, the assays provide a suitable test for the rapid screening for the diagnosis of necrotic enteritis in poultry.     

凹甲陆龟溶组织内阿米巴原虫病的病理组织学观察

对患溶组织内阿米巴原虫病而死亡的凹甲陆龟进行了系统的病理组织学观察，该病的病变主要发生在消化道、肝、心脏、肾、脾等部位，尤以胃肠道和肝病变最为明显，表现为卡他性一坏死性胃肠炎和坏死性一肉芽肿性肝炎，胃肠黏膜出血、水肿、上皮细胞变性、坏死脱落，形成溃疡灶；肝细胞水泡变性，细胞核裂解，肝小叶内可见大小不等的结节性坏死灶，并伴有明显的炎症反应。     

Herpesvirus-like infection of the venom gland of Siamese cobras.

The light and electron microscopic appearance of venom glands from two Siamese cobra snakes with a history of production of poor-quality venom was determined. Light microscopy revealed degeneration and necrosis of patches of columnar epithelial cells of glands and infiltration of the subepithelium by inflammatory cells. The lumina contained debris, venom, and necrotic cells. Electron microscopy revealed a deficiency of microvilli on the luminal surfaces of both degenerated and necrotic epithelial cells. The lumina contained fragmented microvilli, coated vesicles containing venom, and degenerated and necrotic cells. Naked and enveloped herpesvirus-like particles were seen in necrotic and ruptured cells. Occasionally, naked herpesvirus-like particles were seen in the nuclei of attached epithelial cells. It was concluded that herpesvirus-like infection of the venom gland was the probable cause of the production of poor-quality venom.     

Immunoperoxidase evaluation of pneumonic lesions induced by Pasteurella haemolytica in calves

Calves inoculated with Pasteurella haemolytica serovar 1 developed lesions of coagulation necrosis in the lungs that were sharply demarcated by leukocytes. The P haemolytica antigen was detected in the area of coagulation necrosis in histologic sections, using an immunoperoxidase technique. In the central area of the necrotic tissue, the bacterial antigen was diffusely presented in the necrotic alveolar wall, fibrin, serous exudate, and degenerated leukocyte. The bacterial antigen also was found in some groups of degenerating leukocytes around the necrotic tissue. The bacterial colonies among these leukocytes had strong specific reactions against P haemolytica. The bacterial antigen was observed in the cytoplasm of macrophages in alveoli around the necrotic lesion. These findings confirmed that coagulation necrosis is an important lesion in calves with pneumonia caused by P haemolytica.     

Ultrastructural pathology of Bordetella avium infection in turkeys

One-day-old turkeys were infected intranasally with Bordetella avium, and tracheas were examined by scanning and transmission electron microscopy at 1 to 5 weeks post-inoculation (PI). The predominant ultrastructural lesions were progressive loss of ciliated epithelium with replacement by nonciliated cells, bacterial colonization of ciliated cells, membrane-bound crystalline inclusions in cytoplasma of epithelial cells, depletion of mucous granules, and distortion of tracheal rings and the mucosal surface. Tracheal surface exudates consisted of mucus, necrotic cells, heterophils, and fibrin. Ciliated cells were replaced by immature cuboidal cells characterized by abundant rough endoplasmic reticulum with small numbers of electron-dense mucous granules in the apical cytoplasm. Bacterial surfaces were rough and contained numerous pleomorphic, knob-like structures, 20-50 nm in diameter. Other changes included enlarged mucosal gland openings, cell extrusion marks, pleomorphic microvilli, and cells with small numbers of short cilia.     

Focal transmural necrotic tracheitis in commercial meat turkeys

This report describes an unusual presentation of severe focal necrotic tracheitis in a flock of 8-wk-old commercial turkeys. The flock was kept on a range that is located near a cotton field. The cotton field had been chemically defoliated 2 wk before the birds were submitted for necropsy. At necropsy, most of the birds had a 1-cm, yellow-white constricture in the upper third of the trachea at which the lumen was partially occluded by necrotic tissue. Microscopically, there was severe, transmural necrosis with an accumulation of inflammatory exudate in the tracheal lumen and numerous bacteria within the necrotic debris, mucosa, and lamina propria. Mixed bacteria were isolated from the trachea. No viruses were detected. Neither abnormal heavy metal concentrations in the liver nor paraquat in the respiratory tract were detected. The exact cause of this severe, necrotic tracheitis was not determined. Based on the clinical history and laboratory findings, it was concluded that a combination of a toxic irritant, possibly an aerosolized cotton defoliant, and bacterial infections were likely the cause of this lesion.     

Necrotic Enteritis in Broiler Chickens II. Pathology and Proposed Pathogenesis

The intestines from 124 dead, sick and normal broiler chickens from 24 cases of necrotic enteritis were subjected to histological examination. Tissue sections from the duodenum, jejunum, ileum and ceca from each broiler were examined histologically for lesions of necrotic enteritis and the presence of coccidia. Lesions of necrotic enteritis were present in one or more areas of the intestine in all but six of 94 dead or sick birds and they were most common and severe in the jejunum. Coccidia were found in only small numbers in both diseased and normal birds.

Brown and Brenn stained sections showed Gram-positive bacilli intimately associated with early necrotic lesions on the tips of villi. Tissue sections from the intestines of sick birds permitted a proposed pathogenesis for this disease with the lesion starting at the tips of villi.

The similarity in pathogenesis and pathological lesions in this disease of broilers and Clostridium perfringens type C enteritis in baby pigs is discussed.

     

Morphological study in B16F10 murine melanoma cells after photodynamic hyperthermal therapy with indocyanine green (ICG)

Photodynamic hyperthermal therapy (PHT) with indocyanine green (ICG) is a combination of photodynamic therapy (PDT) and hyperthermia (HT). The low toxicity of ICG with an absorption wavelength of 700-800 nm is thought to make it a good candidate as a photosensitizer for PHT. Upon irradiation, ICG produces oxygen radicals and generates heat. The optimal concentration of ICG and the PHT post-irradiation time effects were evaluated by the cytotoxicity of the treatment on B16F10 murine melanoma. The cytotoxicity of PHT was determined based on the morphology of apoptotic and necrotic cells under phase-contrast microscope, confocal laser scanning microscope (CLSM) with DAPI and Annexin V-FITC/PI double staining, and cell surface structure evaluation by scanning electron microscopy (SEM). The use of ICG at a concentration of 150 μM was selected, as cell proliferation was inhibited from 0 to 24 hr post-PHT with a 3-fold decrease in cell viability (P<0.001) compared to the control group. A morphological observation revealed apoptotic and some degree of necrotic features in the PHT-treated cells.     

Hemorrhagic enteritis associated with Clostridium perfringens type A in a dog

A female Shetland sheep dog died suddenly with hemorrhagic diarrhea and vomitting, and was examined pathologically and microbiologically. Gross pathological change was restricted to the intestinal tract. The intestine contained watery, blood-stained fluid. Histopathologically, the principal intestinal lesion was superficial mucosal hemorrhagic necrosis at the jejunoileum. Many Gram-positive bacilli were found adhering to the necrotic mucosal surface in parts of the intestinal tract. Clostridium perfringens in pure culture were isolated from jejunal contents by anaerobic culture. These results suggested that the typical lesion of this case coincided with canine hemorrhagic enteritis and enterotoxemia due to C. perfringens infection could be the cause of sudden death.