Cholangiohepatitis in broiler chickens in Japan: histopathological, immunohistochemical and microbiological studies of spontaneous disease

Forty-five broiler carcasses from 6 different flocks were condemned due to liver lesions at processing meat inspection, and collected for pathological and bacterial examinations. All affected chickens showed liver enlargement with discolouration and an apparent acinar pattern. The enlarged gallbladder and the extrahepatic bile ducts contained yellow inspissated cream-coloured material. Histopathologically, extensive proliferation of bile ductules with fibrosis was observed in interlobular connective tissue, and it spread to form bridges with adjoining triads. Destruction and obstruction of portal bile ducts with multiple granulomas due to bacterial infection and outflow of the bile were frequently observed. Many Gram-positive bacilli were seen in the lesions, and they were identified as Clostridium perfringens by indirect immunofluorescence staining technique. Clostridium perfringens was isolated from affected livers. These findings are consistent with cholangiohepatitis. Therefore, it is suggested that C. perfringens might be important in the pathogenesis of cholangiohepatitis in broiler chickens.     

Etiology and pathogenesis of necrotic enteritis

Sporulated oocysts of Eimeria acervulina were administered orally to cage-housed broilers at a dose of 3.5 X 10(5) resulted in mild subclinical coccidiosis. Clostridium perfringens incorporated in feed at a level of 2.5 X 10(8) organisms/g. produced lesions characteristic of necrotic enteritis. Mortality of 8% (7/80) occurred in birds fed a ration inoculated with Cl. perfringens alone. Mortality of 35% (28/80) was observed in birds which received an oral dose of E. acervulina and which were fed simultaneously with a ration containing Cl. perfringens. Birds which were fed an inoculated ration two days after an oral dose of E. acervulina showed 41% (33/80) mortality. Birds which received an inoculated ration for two days before administration of an oral dose of E. acervulina demonstrated 18% mortality (15/80). Birds which were fed an inoculated ration four days after an oral dose of E. acervulina showed 10% mortality. Infection with E. acervulina reduced the pH of intestinal contents with a simultaneous depression in serum protein. A 39% increase in intestinal passage time from 178 to 248 minutes occurred on the fifth day after infection with E. acervulina. These experiments suggest that necrotic enteritis, attributed to proliferation of a toxigenic strain of Cl. perfringens, followed intestinal stasis and minimal lesions induced by mild intestinal coccidiosis.     

Pathological Studies of “Sudden Death Syndrome” in Broiler Chickens

Sudden death syndrome usually occurs in heavy, fast-growing and healthy-looking broilers. Most of the affected birds are males. The characteristic necropsy changes are seen in well-fleshed broilers with edema and generalized pulmonary congestion, recently ingested feed in the crop and gizzard, distended intestine with creamy content and empty gall bladder. The liver and kidneys are slightly enlarged and the latter have patchy areas of subcapsular hemorrhage. The heart contains clotted blood in the atria but the ventricles are often empty and the left ventricle in particular assumes a hypertrophied appearance.Microscopic examination of heart muscle reveals degeneration of fibers, separation of cardiac muscle fibers by edema and infiltration of heterophils. The lungs have severe vascular congestion, inflammatory cell infiltration in the mucosa of the secondary bronchi and edema fluid in the tertiary bronchi and interlobular connective tissue. The liver has moderate bile duct hyperplasia, periportal hepatitis and mononuclear cell infiltration adjacent to bile ducts which possibly leads to bile duct constriction. The kidneys have subcapsular and parenchymatous hemorrhage.     

Laparoscopic cholecystectomy under field conditions in Asiatic black bears (Ursus thibetanus) rescued from illegal bile farming in Vietnam

Nine adult Asiatic black bears (Ursus thibetanus) previously rescued from illegal bile farming in Vietnam were examined via abdominal ultrasound and exploratory laparoscopy for liver and gall bladder pathology. Three bears demonstrated notable gall bladder pathology, and minimally invasive cholecystectomies were performed using an open laparoscopic access approach, standard 10 to 12 mmHg carbon dioxide pneumoperitoneum and a four-port technique. A single bear required insertion of an additional 5 mm port and use of a flexible liver retractor due to the presence of extensive adhesions between the gall bladder and quadrate and left and right medial liver lobes. The cystic duct was dissected free and this and the cystic artery were ligated by means of extracorporeal tied Meltzer knot sutures. The gall bladder was dissected free of the liver by blunt and sharp dissection, aided by 3.8 MHz monopolar radiosurgery. Bears that have had open abdominal cholecystectomies are reported as taking four to six weeks before a return to normal activity postoperatively. In contrast, these bears demonstrated rapid unremarkable healing, and were allowed unrestricted access to outside enclosures to climb trees, swim and interact normally with other bears within seven days of surgery.     

Experimental biliary cryptosporidiosis in broiler chickens

Biliary cryptosporidiosis was studied by inoculation of 2 x 10(5) Cryptosporidium baileyi oocysts (AU-B1 isolate) into the gall bladders of ten 6-day-old broiler chickens. Clinical signs of disease were not seen. Three of the 10 chickens developed biliary tract infections, based on histologic examination of tissue sections. Lesions seen in the gall bladders of these birds included epithelial hyperplasia and infiltration of the underlying connective tissue with mononuclear leukocytes. One of these birds also had involvement of the hepatic bile ducts. The bile ducts were mildly dilated and contained lesions similar to those seen in the gall bladder. Few to many cryptosporidia were present in the gall bladders and bile ducts of infected birds. Chickens may be of use in the study of biliary cryptosporidiosis, a common sequel to enteric infection in humans with human immunodeficiency virus infection.     

Congenital dilatation of the bile ducts (Caroli's disease) in young dogs

We describe 8 young dogs with congenital dilatation of the intra- and extrahepatic bile ducts and diffuse cystic kidney disease, compatible with Caroli's disease in humans. The dogs were referred between 1980 and 2000 because of chronic disease at an age of 6 months to 3 years. These dogs included 3 Collies, 2 Frisian Stabyhouns, 2 Jack Russell Terriers, and 1 mixed-breed dog. The most common signs were vomiting (6/6), polyuria and polydipsia (4/6), and anorexia (4/6). Ascites was a common finding (4/6). Clinicopathologic abnormalities were available for 6 dogs. All had increased plasma alkaline phosphatase activity and fasting bile acids: increased alanine aminotransferase activity and urea and creatinine concentrations were present in 50% of dogs. Ultrasound examination of the liver showed severely dilated bile ducts without evidence of obstruction, and calcification in all cases but 1. Postmortem examination revealed severe dilatation of the larger intra- and extrahepatic bile ducts. The common bile duct and gall bladder were normal, and the bile system was patent. The ducts contained a clear viscid fluid often with calcified material. Microscopically, marked portal fibrosis was present, often with abnormally structured dilated bile ducts lined with columnar or cuboid epithelium and regularly small calcifications. The lesion was complicated by ascending cholangitis in 1 dog. The kidneys showed marked cortical and medullary fibrosis with a diffuse radial cystic pattern; only slight renal fibrosis was found in the oldest dog. Seven dogs were euthanized without treatment; the oldest dog was alive and well 5 months after diagnosis and was maintained on a protein-restricted diet.     

Extrahepatic Biliary Tract in Chinchilla (Chinchilla laniger,Molina)

The aim of the study was the macromorphological analysis of extrahepatic biliary tract in chinchilla (Chinchilla laniger Molina). Bile ducts, the gall bladder and portal vein were injected with coloured latex. Using the technique of dissection, bile ducts were isolated from the liver lobes. It was found that the cystic duct in this species is rarely single. Hepatic ducts form a system of multiple anastomosing structures running in the hepatoduodenal ligament. Many bile duct openings were observed in the duodenal papilla. The results confirm wide variations of the biliary tract in mammals and may be important for comparative analysis of the morphological differentiation of these structures in small mammals.     

SONOGRAPHIC EVALUATION OF EXPERIMENTAL BILE DUCT LIGATION IN THE DOG

The common bile duct was surgically ligated in five normal adult dogs. Ultrasonographic examinations of the gallbladder and biliary system were performed after duct ligation at intervals of 24 hours. The sequence of biliary system dilation was from the common duct to the peripheral intrahepatic ducts. Common duct enlargement was evident in 24–48 hours, while peripheral biliary duct dilation was recognized by five to seven days after obstruction. When compared with hepatic and portal veins, dilated biliary ducts were more tortuous and had irregular branching patterns. Gross pathologic changes were correlated with ultrasonographic findings at seven, 14, 15, 18 and 21 days after obstruction.     

Congenital dilatation of the large and segmental intrahepatic bile ducts (Caroli's disease) in two Golden retriever littermates

Two, sibling, male Golden retriever puppies, 13 weeks of age, were presented with congenital biliary cysts of the liver involving both hepatic and segmental bile ducts, as well as bilateral polycystic kidney disease. Ultrasonography of the livers of both pups demonstrated segmental cystic lesions that were contiguous with the bile ducts. Histopathology revealed cystic ectatic bile duct hyperplasia and dysplasia with variable portal fibrosis in the liver, while in the kidneys there were radially arranged, cylindrically dilated cysts of the collecting ducts, which extended through the medulla and cortex. This pathology was compatible with that of congenital dilatation of the large and segmental bile ducts (Caroli's disease) described in humans, dogs and rats. In humans Caroli's disease has an autosomal recessive inheritance pattern, while in rats activation of the MEK5/ERK cascade initiates the biliary dysgenesis of Caroli's disease in this species. However, the exact mode of inheritance and pathogenesis of Caroli's disease in dogs is as yet unknown. Previous reports on congenital hepatic cystic diseases of the dog have described Caroli's disease like lesions in various breeds, but these are believed to be the 1st reported cases in the Golden retriever breed.     

Jaundice in the cat associated with inflammation of the biliary tract and pancreas

A 7-year-old Siamese cat had recurrent episodes of pyrexia, anorexia, weight loss and jaundice. There was biochemical evidence of hepatic damage and hyperbilirubinaemia. At necropsy there was catarrhal and fibrosing inflammation of the biliary ducts, gall bladder and pancreas. The lesion was probably a sequel to ascending infection of the biliary and pancreatic ducts. Although this combination of lesions is not uncommon in cats, associated clinical disease appears to be infrequent.     

The excretion of phylloerythrin and bilirubin by calves and sheep.

Under general anaesthesia the common bile duct was ligated in two sheep and two calves. Occlusion of the duct was permanent and was followed by portal fibrosis, proliferation of bile ducts and intrahepatic bile stasis. Mild hepatic cell damage was accompanied by the release of glutamate dehydrogenase, sorbitol dehydrogenase and arginase into serum. The release of gamma-glutamyl transpeptidase was slower but more continuous. One sheep and one calf developed peritonitis associated with the leakage of bile from a biopsy wound in the live. One of these animals and the other two on which biopsy was not performed became photosensitised on exposure to sunlight. The concentration of phylloerythrin was high in serum and urine. All animals became jaundiced and the increased concentration of bilirubin in serum and urine was mainly direct reacting, ie, conjugated with glucuronic acid.     

Pathogenesis of aleutian mink disease. VII. Chronic hepatitis with bile duct proliferation]

Aleutian disease is a chronic persistent viral infection of mink characterized by hypergammaglobulinema, generalized plasmacytosis, sclerosing glomerulonephritis, polyarteritis, and plasma cell hepatitis with bile duct proliferation. The development of hepatic lesions was studied both light- and electron-microscopically in mink experimentally infected with Aleutian disease virus. Fifteen normal and 99 mink experimentally infected with Aleutian disease virus were used. Experimental mink were killed in intervals from 3 weeks to 23 months after infection, and liver sections were processed for both light- and electron-microscopic studies. Experimentally infected mink developed portal and intralobular lymphocytic and plasmacytic infiltrates in the liver 3 weeks after infection. Four to five weeks after infection there was evidence of early bile duct proliferation that began as an outgrowth of the portal bile ducts. Three to five months after infection a marked bile duct proliferation was present in some of the portal triads and adjacent liver lobules; but there was no tendency of these lesions to progress into biliary cirrhosis. Ultrastructural characteristics of proliferating bile duct cells were marked deformation, formation of multiple cell layers, reduction in the number of microvilli and desmosomes, and infiltration of the epithelial cells by lymphoid cells and plasmacytes. The hepatic lesions either develop by direct virus stimulation or by the deposition of virus-antibody complexes.     

Gall bladder rupture associated with cholecystitis in a domestic ferret (Mustela putorius)

A six‐year‐old neutered female albino ferret was presented with an acute episode of lethargy and anorexia. Clinical examination revealed marked cranial abdominal pain. A severe neutrophilic leukocytosis was present. Abdominal ultrasound was consistent with a diffuse peritonitis and severe bile duct inflammation. Cytology of the abdominal effusion revealed bile peritonitis. An exploratory laparotomy was performed and the gall bladder appeared inflamed with multiple perforations. A cholecystectomy was performed. The ferret recovered without complication. Bacteriological culture of the bile and gall bladder yielded a pure growth of Pseudomonas aeruginosa. Histopathological analysis of the gall bladder and liver was consistent with a marked cholecystitis and cholangiohepatitis. On the basis of sensitivity testing, the ferret was treated with marbofloxacin for one month. No complications or reoccurrence were seen up to 1 year after the diagnosis. To the author's knowledge, this is the first report of bile peritonitis secondary to gall bladder rupture in a ferret.     

Effects of Eimeria brunetti infection and dietary zinc on experimental induction of necrotic enteritis in broiler chickens.

Broilers infected with Eimeria brunetti and given dietary zinc were examined for experimental induction of necrotic enteritis. Inoculation with sporulated E. brunetti oocysts at 7 days of age was followed by 5 consecutive days of oral inoculation with cultured Clostridium perfringens. Feed was supplemented with zinc at 1000 ppm. Upon necropsy of broilers 6 days after coccidial inoculation, necrotic enteritis was found in 20% (2/10) of birds given both organisms and dietary zinc. Coccidial lesion scores were also highest in that group. Birds infected with E. brunetti and C. perfringens with no dietary zinc had significantly higher coccidiosis lesion scores (P less than 0.05) than groups inoculated with E. brunetti only, regardless of zinc supplementation. Alpha toxin levels in intestinal contents were low in groups infected with both organisms, regardless of zinc supplementation. Zinc was tested for effects of alpha toxin production in vitro. In the mid-log phase (6 hours incubation), a high level of alpha toxin was produced in zinc-supplemented media, but this was lost quickly in the presence of trypsin. Addition of zinc partly protected the toxin from the action of trypsin.     

A morphologic and immunocytochemical study of hepatic neoplasms in cats.

A retrospective study was done of 47 neoplasms of the hepatic and biliary systems from 47 cats brought to The Animal Medical Center over a period of 10 years (1980 to 1989). Histologic examination of specimens taken at necropsy revealed that 87% (41/47) of the hepatic neoplasms were epithelial and 13% (6/47) were nonepithelial. Of the epithelial tumors, 25/47 (53%) were of intrahepatic bile duct origin, 9/47 (19%) were of hepatocellular origin, 5/47 (11%) involved the extrahepatic bile ducts, and 2/47 (4%) were adenocarcinomas of the gall bladder. Of the nonepithelial neoplasms, hemangiosarcomas were more common, 5/47 (11%), than leiomyosarcomas, 1/47 (2%). Multiple liver lobes were involved in 21/34 (62%) of the epithelial and all six of the nonepithelial intrahepatic neoplasms. Most of the bile duct adenocarcinomas (6/9) were predominantly characterized by acinar structures with mucin production, diffuse necrosis, and little desmoplasia. The hepatocellular carcinomas were characterized by three patterns-trabecular (five tumors), pseudoglandular pattern (two tumors), and anaplastic (one tumor). The hepatic carcinoid was characterized by various-sized groups of acinar and rosettelike structures, some with lumens, separated by thin fibrovascular stroma. The extrahepatic bile duct adenocarcinomas (4/4) were acinopapillary with moderate desmosplasia, whereas the adenocarcinomas of the gall bladder had elongated tubular structures lined by anaplastic cells and a severe desmoplastic reaction. The neuroendocrine carcinoma of the extrahepatic bile duct, the hemangiosarcomas, and the leiomyosarcoma had morphologic features characteristic of these neoplasms. Two of the 16 (13%) bile duct adenomas had anaplastic and precancerous changes. Residual benign components were seen in 10/15 (67%) of the biliary adenocarcinomas, 4/9 (44%) of the intrahepatic bile duct adenocarcinomas, and all of the extrahepatic bile duct adenocarcinomas and gall bladder adenocarcinomas. Results of immunohistochemical studies of the biliary neoplasms were similar to those described in studies of biliary neoplasms in human beings. Results of this study revealed that the frequency of different types of hepatic neoplasms in cats varied from that seen in dogs and human beings, but the morphologic features were comparable.     

Light microscopic and electron microscopic changes in the livers of cats with extrahepatic bile duct obstruction

Light microscopic and transmission electron microscopic changes were studied in the livers of 6 cats at 25 to 54 days after their extrahepatic bile ducts were experimentally obstructed. Histologic findings included various degrees of bile duct dilatation, ductular proliferation, and peribiliary fibrosis. Concentric layers of dense, birefringent connective tissue surrounded midsized bile ducts. The degrees of bile duct proliferation, hepatocellular degeneration, and bile retention were similar in each cat, but the amount of periductular connective tissue increased with chronicity of bile duct obstruction. Ultrastructural changes included marked swelling of endoplasmic reticulum and mitochondrial inner compartments, marked dilatation and distention of the canaliculi by bile casts, and numerical reduction of canalicular microvilli. Microvilli were often swollen and blunt. Mitochondria were swollen and long, and the cristae lacked normal distribution and density. Cytoplasmic accumulations of granular, electron-dense material and concentrically laminated arrays of material indicative of bile substances were also observed.     

Duplex gall bladder associated with choledocholithiasis, cholecystitis, gall bladder rupture and septic peritonitis in a cat

A 10-year-old cat was presented with a history of inappetence, pyrexia and weight loss. Clinical investigations showed anaemia, hyperbilirubinaemia, septic peritonitis and a double gall bladder with choleliths in an extrahepatic duct. Initial medical stabilisation was performed. At laparotomy, a duplex gall bladder with two separate cystic ducts was identified. The left gall bladder was thickened and had ruptured at the apex. Multiple choleliths were identified in the left cystic duct. The right gall bladder and cystic duct were grossly normal. The ruptured gall bladder was repaired, the gallstones were removed via a choledochotomy of the left cystic duct and a choledochoduodenostomy was created from the dilated left cystic duct. The cat remained depressed and anorexic, and it was euthanased 72 hours postoperatively at the owners' request. This is the first ante-mortem investigation of extrahepatic biliary disease associated with gall bladder duplication in the cat.     

Toxin production by Clostridium perfringens isolated from broiler chickens and capercaillies (Tetrao urogallus) with and without necrotizing enteritis.

A total of 192 isolates of Clostridium perfringens were isolated from 99 broiler chickens and 93 capercaillies (Tetrao urogallus). Fifty of the isolates from broilers and 44 of the isolates from capercaillies were from birds with necrotizing enteritis, and the remainder were from birds without this disease. The isolates were tested for the production of three major toxins (alpha, beta, and epsilon) and four minor toxins (theta, gelatinase, mu, and nu). All isolates were found to be C. perfringens type A. Alpha toxin was produced in significantly larger amounts by isolates from birds with necrotizing enteritis than by isolates from birds without the disease, regardless of bird species. Isolates from broilers produced significantly more alpha toxin than did isolates from capercaillies.     

Isolation of Escherichia coli O157:H7 from the gall bladder of inoculated and naturally-infected cattle

To determine if Escherichia coli O157:H7 is capable of residing in the gall bladder of cattle, inoculation studies were conducted with O157:H7 strain 86-24 in weaned Holstein calves. Strain 86-24 was isolated from the gall bladders of five calves 36 days after inoculation. Two other calves contained the inoculation strain in the distal colon but the organism was absent in their gall bladders. A second trial in which the calves were euthanized 15 days after inoculation found strain 86-24 in six of seven inoculated calves but only in colon and/or rumen samples. In a third trial that inoculated eight calves with a four-strain cocktail of O157:H7 strains, the gall bladders from all eight animals were positive 9 days after inoculation. The colon and rumen samples from these calves were also positive. E. coli O157:H7 isolates recovered from bile samples and subtyped by pulsed field gel electrophoresis found that three of the four inoculation strains were present in one or more of the calves. Thus, residence in the gall bladder is not restricted to a single strain. Additional evidence of the ability to localize in the gall bladder of cattle was provided by testing the bile from 150 gall bladders (five collection dates, 30 samples each) obtained at an abbatoir and the isolation of E. coli O157:H7 from four samples (2.7%). This study establishes that E. coli O157:H7 can reside transiently or permanently at a low level in the gall bladder of cattle.