Thirteen coagulation tests evaluating hemostatic and fibrinolytic indices and serum cytokine and plasma endotoxin concentrations were obtained in 34 foals with a positive sepsis score (septic group) and 46 age-matched healthy foals. Compared to healthy foals, the prothrombin, activated partial thromboplastin, and whole blood recalcification times were significantly longer in septic foals. The fibrinogen and fibrin degradation products concentrations, percent plasminogen, alpha-2 antiplasmin, and plasminogen activator inhibitor activities, and tumor necrosis factor and interleukin-6 activities were greater in septic foals. Protein C antigen and antithrombin I11 activity were significantly lower in septic foals. Blood cultures were positive for growth and endotoxin was detected in 19 of 29 and 15 of 30 septic foals, respectively. In septicemic foals with detectable endotoxin in the plasma, the prothrombin and activated partial thromboplastin times were significantly longer and the plasminogen and antithrombin I11 activities were significantly less than in septic foals in which endotoxin was not detected. Twenty-three of the 34 septic foals did not survive. Septic foals that did not survive were most likely to have a positive blood culture in which a gram-negative organism was isolated. Histopathologic evidence of hemorrhage was evident in 11 foals at postmortem examination and thrombosis was identified in 2 foals. The prothrombin time was significantly longer in foals that had multisite hemorrhage at postmortem examination. The results of this study indicate that clinically relevant alternations in hemostatic and fibrinolytic indices occur in neonatal foals with septicemia and that derangements can be correlated with the presence of endotoxin in plasma. Derangements in hemostatic or fibrinolytic indices were helpful in identification of septic foals with increased risk of coagulopathy, but were not helpful in predicting hemorrhage as compared to thrombus formation. Survival of septicemic foals was correlated with grarr-negative bacteremia, but not with the presence of endotoxin or coagulopathy.Key words: Coagulation; Endotoxin; Equine; Fibrinolysis; Hemostasis; Neonate; Sepsis.epticemia is a common cause of death in equine neo-S nates.' The most common etiologic agents isolated in foals with septicemia are gram-negative bacteria. Endotoxin, a lipopolysaccharide component of the outer cell membrane of gram-negative bacteria, is released during cell multiplication or bacteriolysis. Consequently, endotoxemia is a common sequela to gram-negative septicemia in foals2Endotoxemia has been associated with higher mortality rates in septicemic human patients and adult horses with gastrointestinal d i~e a s e .~.~ Endotoxin exerts its detrimental effects on the host by interacting with components of the coagulation, inflammatory, and immune s y s t e m~.~.~ During endotoxemic or septic shock, the delicate balance of procoagulant, anticoagulant, and fibrinolytic factors that maintains homeostasis of the coagulation system is ...

Abstract. Cytologic and histologic examination of 91 canine mammary masses was performed by two cytologists and two histopathologists. Ten important cytologic criteria of malignancy for canine mammary tumors were identified. A cytologic grading system for differentiation of benign from malignant mammary tumors was proposed using these criteria. With this system, approximately one fourth of the malignant mammary tumors were given a concordant cytologic diagnosis. Approximately one-half of the benign masses were given a concordant cytologic diagnosis by the two cytologists. One-half of all the tumors examined were given inconclusive cytologic diagnoses by both cytologists. The cytologic identification of spindle cells did not differentiate complex and mixed mammary tumors from simple tumors. Only five of the animals studied died of mammary cancer, precluding a critical analysis of the cytologic criteria for prediction of cancer mortality.Tumors of the mammary gland are a common clinical problem in the adult bitch, comprising up to 52% of all neoplasm^.^ The frequency of malignancy among mammary tumors is approximately 50%.4~8~28 The disease is commonly multicentric, and tumors in a single dog may be of more than one type.9,25,32.36 Clinical findings identified by history or physical examination that could indicate malignancy include a tumor diameter of greater than 5 cm, recent rapid growth, infiltration of surrounding tissues, erythema, and edema.3,4,34 Most canine mammary tumors (Le., benign and malignant) exhibit none of these findings. Other prognostic indicators (i.e., cellular differentiation and invasion of surrounding stroma) are identifiable only through histologic examination. Since the most common treatment for canine mammary neoplasia is surgical excision, definitive therapy often is pursued prior to diagnosis of the disease.The safety of fine needle aspiration cytology as a preoperative diagnostic test of breast cancer in women has been e s t a b l i~h e d .~,~~ It has been shown to be highly accurate (false positive rate less than 1%) in studies comparing cytologic with subsequent histologic findings.11,20,43,44 In a comparable study in the dog, 19 mammary tumors were examined cytologically and histologically. Eight out of 17 mammary carcinomas were given a concordant cytologic diagnosis, and two adenomas were diagnosed cytologically as carcinoma. l5

Hemostatic indices were determined in 45 healthy light breed foals, from birth to 1 month of age, and in 20 healthy adult (> 2 years of age) light breed horses. Blood samples were obtained from each foal at 4 ages: 1) < 24 hours, 2) 4-7 days, 3) 10-14 days, and 4) 25-30 days. The following hemostatic indices were determined: platelet count; prothrombin and activated partial thromboplastin times; activity concentrations of protein C, antithrombin III, plasminogen, alpha-2 antiplasmin, tissue plasminogen activator, and plasminogen activator inhibitor-1; plasma protein C antigen and fibrinogen concentrations; and serum fibrin degradation products concentration. Prothrombin and activated partial thromboplastin times were significantly longer at birth than in older foals. The plasma concentrations of the following were significantly lower at birth than in older foals: antithrombin III, plasminogen and tissue plasminogen activator activities, protein C antigen, and fibrinogen. Concentrations of the following were significantly higher at birth than in older foals: protein C and plasminogen activator inhibitor-1 activities and fibrin degradation products. These results indicate that hemostatic indices of neonatal foals differ significantly from those of older foals and adults. With the exceptions of antithrombin III and tissue plasminogen activator activities, all hemostatic indices measured in foals at 1 month of age were equivalent to adult values.

Abstract. Wedge biopsy of the liver during episodic clinical illness in three male cats showed chronic lymphocytic cholangitis. Principal clinical findings were increased serum alkaline phosphatase activity and hepatomegaly (two cats) associated with anorexia, pyrexia, and weight loss; these signs of illness were intermittent with asymptomatic periods. The hepatic lesions were characterized by lymphoid aggregate or follicle formation, diffusely dispersed lymphocytes and plasma cells, and abnormal bile ducts and ductules. Lymphoid aggregates and diffusely scattered lymphocytes were seen in the pancreas also. The spectrum of hepatic lesions in three cats seemed to represent a progression in the development of the disease. Similarities and dissimilarities between the findings in the three cats and human primary biliary cirrhosis or chronic nonsuppurative destructive cholangitis are discussed. During a prospective search for cats with this disease, other hepatic lesions were found, and it was concluded that cats may be affected by more than one pathogenic mechanism culminating in chronic cholangitis or cholangiohepatitis.Hepatic disease and icterus are common in cats, and the spectrum of lesions is diverse. The cause and pathogenesis are difficult to determine in most cases. Feline hepatic syndromes have been described, however, including hepatic lipidosis [ 11, cholelithiasis and biliary obstruction [lo], Platynosomum infection [ 1 11, cholangitis or cholangiohepatitis [5, 6, 161, and metastatic or primary neoplasia [9]. One report of chronic cholangitis in a cat relates a clinical response to corticosteroid treatment [161.Inflammatory disease of the biliary tract may coexist with chronic interstitial pancreatitis [5]. The lesions may be related in cats because the bile duct and pancreatic duct fuse before entering the duodenum. The pancreatic lesions are characterized by interstitial fibrosis and infiltrates of mononuclear inflammatory cells [5]. Another report describes a cat that had periodic episodes of illness characterized by anorexia, pyrexia, icterus, and progressive weight loss [6]. The lesions were cholangitis, bile duct hyperplasia, and pancreatic interlobular fibrosis.At a recent regional veterinary pathology conference, a feline hepatic lesion characterized by lymphocytic cholangitis, biliary fibrosis, and bile duct hyperplasia was reported (Dr. J. Orr, Western College of Veterinary Medicine, Saskatoon, 99

Abstract. Sixty-four canine cutaneous round cell tumors were divided into 25 mast cell tumors, I5 histiocytomas, nine cutaneous lymphosarcornas and 15 transmissible venereal tumors. The final diagnosis was made from cytologic, clinical and histologic findings. Cytologic features were significantly distinctive in mast cell tumor, transmissible venereal tumor, and most cases of histiocytoma and lymphosarcoma to allow a diagnostic opinion. This opinion was supported by subsequent histologic examination. In some instances cytology was considered essential in rendering a diagnostic opinion even though histology was available.In the dog, skin and subcutis are the most common sites for neoplasms, accounting for 67.5% of the neoplasms in one survey [3]. We have found that round cell tumors of the skin make up a significant percentage of these dermal neoplasms. Round cell tumors consist of discrete cells that are round to oval rather than fusiform. Included in this group are mast cell tumor, histiocytoma, lymphosarcoma (including reticulum cell sarcoma) and transmissible venereal tumor. Melanotic tumors occasionally appear as round cell tumors but are not included here. Because the histologic pattern of these neoplasms is often similar, cytologic examination of touch imprints or fine needle aspirations of tumors often can be a valuable adjunct to rendering a definitive diagnosis. The differential diagnosis of round cell tumors by histologic examination without concomitant cytologic characterization may, in some instances, depend more on age of animal, growth rate, location of tumor, number of tumors and lymph node involvement rather than histologic criteria.There have been isolated cytologic descriptions of some of the round cell tumors [2, 4, 5, 8-10]. Our purpose here is to present the cytologic characteristics of canine cutaneous round cell tumors, including those on the external genitalia, and to encourage the use of cytology in the diagnosis of these tumors. 673