Fish: serologic evidence of infection with human pathogens

Specific antibodies to several bacteria pathogenic to humans were detected in the serums of white perch from surface waters adjacent to heavily populated areas on Chesapeake Bay. White perch from surface waters adjacent to sparsely populated areas were free of such antibodies. We suggest that fish may become actively infected with human pathogens by exposure to contaminated water and may constitute a hazard to public health.     

Effects of exercise on the hemostatic system of thoroughbred horses displaying post-exercise epistaxis

Hemostatic parameters in 5 Thoroughbreds which had recently displayed post-exercise epistaxis, and 4 normal horses, were assessed using blood samples taken when the animals were at rest, immediately before exercise, and 5 minutes after galloping 1.2. km at maximum speed. Exercise resulted in marked depression in the adenosine diphosphate (ADP)-induced aggregation response of platelets from both groups of horses. No significant differences were detected when comparing the results from each group. However, there was a tendency for the platelets from the bleeder group to be less responsive to ADP. Because not all aspects of platelet function were studied the possible role of platelet abnormalities in the pathogenesis of exercise-induced pulmonary hemorrhage could not be completely discounted.     

Haemorrhagic disease of lagomorphs: evidence for a calicivirus.

Studies on the aetiological agents of rabbit haemorrhagic disease (RHD) and European brown hare syndrome show that the viruses responsible for these infections can be placed in the family Caliciviridae. Established members of this group are vesicular exanthema virus (prototype), San Miguel sea lion virus and feline calcivirus. The human hepatitis E virus and the Norwalk agent may soon be included. The RHD virus genome consists of a positive stranded RNA molecule composed of 7437 nucleotides. A major subgenomic RNA of 2.2 kb, colinear with the 3' end of the genomic RNA, can also be recovered from infected liver tissue, and both RNAs are enclosed within viral capsids formed by a single major protein of approximately 60 kDa. Electron microscopic examination of organ suspensions from diseased animals shows two types of particle; 35-40 nm complete virions have the regularly arranged cup-shaped depressions typical of calcivirus morphology, and 23-25 nm smooth particles resulting from degradation of the outer surface structures of the complete virions.     

Short-limbed dwarfism and ocular defects in the Samoyed dog

A syndrome of short-limbed dwarfism and ocular defects was found in Samoyed dogs. The most prominent abnormalities were small stature and valgus deformity of the carpi. Radiographic evidence of retarded growth at the distal ulnar physis was apparent by 12 weeks of age. Ocular defects included cataracts and retinal detachment. Family studies and limited breeding experiments were consistent with an autosomal recessive mode of inheritance.     

Anti-A isoagglutinins in two blood type B cats are IgG and IgM

Sera from two blood type B cats had strong isoagglutinating and isohemolyzing titers against blood type A erythrocytes. In order to determine the class of the immunoglobulins, sera from the cats were pooled, ammonium sulfate precipitated, and gel filtered using sepharose 6B to separate the immunoglobulins by molecular size. The immunoglobulin concentrate separated into two fractions. The initial part of the first fraction was shown in an ELISA to contain IgM and to be devoid of IgG by immunoelectrophoresis and to have agglutinating activity (a titer of 1:4 with a protein concentration of 0.8 mg/ml). Treating this fraction with the reducing agent dithiothreitol (DTT) eliminated agglutinating activity. The latter portion of the second column fraction was shown to contain IgG by immunoelectrophoresis, and to be devoid of IgM by ELISA. Agglutinating activity was also present in the second fraction (a titer of 1:2 with a protein concentration of 1.9 mg/ml); hemagglutinating activity was not decreased by DTT treatment. These studies show that the predominant anti-A isoagglutinating activity in pooled sera from two blood type B cats is IgM and that some isoagglutinin activity can be associated with IgG.     

Synchronization of estrus in dairy goats treated with prostaglandin F at various stages of the estrous cycle.

Dairy goats were given IM injections of 125 micrograms of cloprostenol sodium on day 6 of the estrous cycle (prostaglandin F [PGF] 6, n = 22) or day 12 of the estrous cycle (PGF 12, n = 26). Mean +/- SE hours from injection to onset of behavioral estrus and proportion of goats responding were 46 +/- 4.2 (range, 12 to 88 hours) and 95% and 48 +/- 2.9 (range, 34 to 68 hours) and 100% for groups PGF 6 and PGF 12, respectively. There was no significant difference between the groups in mean time to onset of estrus, but variances about the means were different. Of the does in groups PGF 6 and PGF 12, 67 and 85%, respectively, had signs of onset of estrus between 36 and 60 hours after administration of PGF. Mean (+/- SE) hours from injection to time of peak concentrations of luteinizing hormone (LH) were 62 +/- 3.1 and 64 +/- 2.1 for groups PGF 6 and PGF 12, respectively. Of the does in groups PGF 6 and PGF 12, 86 and 100%, respectively, had LH peaks. Of the does in groups PGF 6 and PGF 12, 68 and 77%, respectively, had peak concentrations of LH between 48 and 72 hours after administration of PGF. All does in groups PGF 6 and PGF 12 had concentrations of progesterone greater than or equal to 1.0 ng/ml on the day of administration of PGF. Concentrations decreased to less than 1.0 ng/ml by 48 hours after injection in all does except 1 in group PGF 6.(ABSTRACT TRUNCATED AT 250 WORDS)     

Proteins encoded in the 5' region of the pestivirus genome--considerations concerning taxonomy.

The first protein encoded within the pestivirus open reading frame is a nonstructural protein which removes itself from the polyprotein by autoproteolytic cleavage. The following nucleocapsid protein ends just before a putative signal sequence preceding three glycosylated proteins. All three glycoproteins are part of the viral envelope and exist in the form of disulfide-linked dimers. Pestiviruses have recently been reclassified as members of the family Flaviviridae which now comprises three genera, namely flavivirus, hepatitis C virus group and pestivirus. All members of the family have certain characteristics in common like the overall genome organization and the strategy of gene expression. Major differences exist, however, between the genera; the most obvious ones concern proteins encoded in the 5' region of the respective genomes.     

Alterations in coagulation and hemograms of horses given endotoxins for 24 hours via hepatic portal infusions

This experiment was designed to establish a model for the study of gastrointestinal disturbances as a result of prolonged endotoxin uptake in the horse. The hepatic portal vein of 7 horses was catheterized (through flank incisions) to give chronic hepatic portal infusions of lipopolysaccharide (LPS, endotoxin). Lipopolysaccharide was infused at a rate of 1 microgram/kg of body weight/hr for 24 hours. Two of the horses were infused with saline solution for 12 hours before LPS infusions were given. Lipopolysaccharide was shown to affect behavior and hematologic and coagulation values. The 1st hour was critical for the LPS-infused horses; yet by 4 hours, the horses had apparently become refractory to continued infusion of LPS. During the 1st hour, all horses collapsed without an accompanying hypotension. A decrease in polymorphonuclear leukocytes (neutrophils) was seen during this time and was accompanied by a shortening of the recalcification tests, 1-stage prothrombin time, and activated partial thromboplastin time. There was an increased concentration of circulating fibrinogen/fibrin degradatory products. All of the LPS-infused horses showed signs of hoof discomfort and either stood with the 4 feet together beneath the body or continually shifted their weight from one front foot to the other. Hoof temperature decreased approximately 3 degrees (C) during this time and remained decreased for the duration of the experiment.