Analysis of the 96 most often cited articles published in veterinary journals in 2002 and 2003

Summary The study concerned 123 Journals of the category "Veterinary Sciences" as defined in the Journal Citation Reports (?, Institute for Scientific Information (ISI), Philadelphia, USA). Using Web of Knowledge (?, ISI, USA), update December 3, 2005, articles published in 2002 and 2003 and cited 20 times or more were selected. The total number of selected articles was 96. They were published in 34 out of the 123 journals. Based on the country of the first author, the articles originated form 24 countries. Forty-nine of the 96 articles (51%) were written in only two countries being England (15) and the USA (34). The articles could be classified in six categories being immunology (21), microbiology and directly related subjects (48), prions and prion-induced diseases (5), reproduction (23), toxicology (3), and miscellanea (11). The category "microbiology" (48) was divided into six subcategories: general (1), bacteriology (17), mycology (3), parasitology (5), protozoology (6), and virology (5). Some articles were classified in more than one (sub)category.     

Hepatocholangiocellular carcinoma in a rat--case report

A mixed epithelial tumour in the liver of a 24-month-old male Wistar rat from a 30-month inhalation study is described. The rat, which was in a group exposed to low concentrations of diesel exhaust, was euthanized because of emaciation, forced respiration and abnormal gait. Macroscopic examination of the enlarged liver revealed multiple partly confluent beige-red nodules up to 1.5 cm in diameter. Small nodules up to 7 mm in diameter were seen in the spleen. Histologically, the tumour nodules in the liver consisted of hepatocellular and cholangiocellular components. The hepatocellular component consisted of moderately differentiated polygonal to round hepatocytes about twice as large as normal hepatocytes and having hyperchromatic, centrally located nuclei with prominent nucleoli and eosinophilic cytoplasm. Foci of haematopoiesis and focal necroses were prominent. The cholangiocellular component was moderately differentiated and consisted of tubular structures lined by low cuboidal to cylindrical cells showing cytoplasmic basophilia and small dark nuclei without prominent nucleoli. The histological features of the nodules in the spleen corresponded to those of the primary tumour in the liver. Based on these criteria, the tumour nodules were diagnosed as hepatocholangiocellular carcinoma. The immunohistological examination confirmed the diagnosis, i.e. immunostaining for cytokeratins was positive for eight and 18 (hepatocellular carcinoma) and for seven and 19 (cholangiocellular carcinoma) as well as for vimentin (dense fibrous stroma). This tumour is considered to be spontaneous because of its single occurrence.     

Classification of abomasal displacement in cows according to histopathology of the liver and clinical chemistry

Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types.     

The effects of formulation on the immunostimulatory activity of dihydroheptaprenol

Holstein steer calves received a single injection of Miglyol (Sasol Chemical Industries, Ltd.) subcutaneously as a placebo, dihydroheptaprenol (DHP) (4 mg/kg) emulsified with lecithin subcutaneously, DHP in solution in Miglyol (4 mg/kg) subcutaneously, or DHP in solution in Miglyol (4 mg/kg) intranasally. The DHP emulsified in lecithin emulsion administered subcutaneously caused a substantial increase in body temperature, total leukocyte count, total neutrophil count, neutrophil cytochrome-c reduction, and neutrophil iodination 24 hours after administration and, for some of the parameters, at 48 hours. The DHP formulation in Miglyol did not have any of these effects when administered subcutaneously or intranasally. The carrier and formulation of DHP apparently have major effects on the biologic activity of DHP.     

High intensity exercise conditioning increases accumulated oxygen deficit of horses

High intensity exercise is associated with production of energy by both aerobic and anaerobic metabolism. Conditioning by repeated exercise increases the maximal rate of aerobic metabolism, aerobic capacity, of horses, but whether the maximal amount of energy provided by anaerobic metabolism, anaerobic capacity, can be increased by conditioning of horses is unknown. We, therefore, examined the effects of 10 weeks of regular (4-5 days/week) high intensity (92+/-3 % VO2max) exercise on accumulated oxygen deficit of 8 Standardbred horses that had been confined to box stalls for 12 weeks. Exercise conditioning resulted in increases of 17% in VO2max (P<0.001), 11% in the speed at which VO2max was achieved (P = 0.019) and 9% in the speed at 115% of VO2max (P = 0.003). During a high speed exercise test at 115% VO2max, sprint duration was 25% longer (P = 0.047), oxygen demand was 36% greater (P<0.001), oxygen consumption was 38% greater (P<0.001) and accumulated oxygen deficit was 27% higher (P = 0.040) than values before conditioning. VLa4 was 33% higher (P<0.05) after conditioning. There was no effect of conditioning on blood lactate concentration at the speed producing VO2max or at the end of the high speed exercise test. The rate of increase in muscle lactate concentration was greater (P = 0.006) in horses before conditioning. Muscle glycogen concentrations before exercise were 17% higher (P<0.05) after conditioning. Exercise resulted in nearly identical (P = 0.938) reductions in muscle glycogen concentrations before and after conditioning. There was no detectable effect of conditioning on muscle buffering capacity. These results are consistent with a conditioning-induced increase in both aerobic and anaerobic capacity of horses demonstrating that anaerobic capacity of horses can be increased by an appropriate conditioning programme that includes regular, high intensity exercise. Furthermore, increases in anaerobic capacity are not reflected in blood lactate concentrations measured during intense, exhaustive exercise or during recovery from such exercise.     

Retrieval of a patent ductus arteriosus coil following embolisation to the right subclavian artery

A two-month-old female Tibetan terrier was re-presented with an incomplete closure of the patent ductus arteriosus. Following a second attempt to close the shunt by coil embolisation, arterial embolisation occurred. The successful removal of the embolised coil is described.     

Neurological dysfunction in three dogs and one cat following attenuation of intrahepatic portosystemic shunts

Neurological dysfunction is an uncommon complication following extrahepatic portosystemic shunt ligation. Three dogs and one cat are described that developed neurological signs within 21 to 42 hours of attenuation of intrahepatic portosystemic shunts. None of these cases had biochemical evidence of hepatic encephalopathy postoperatively. Two dogs died during management of status epilepticus following aspiration of food. One dog died six months postoperatively. The cat had persistent neurological dysfunction at discharge, but was alive and had recovered most of its neurological function at the time of writing, 37 months after surgery. This report demonstrates the potential for animals with intrahepatic portosystemic shunts to develop postoperative neurological signs and highlights the difficulty of managing such cases. Two dogs had both intrahepatic and extrahepatic portosystemic shunts. Large intestinal malrotation (partial situs inversus) may have been linked to the development of a portosystemic shunt in the remaining dog.     

Neurogenesis in a young dog with epileptic seizures

Epileptic seizures can lead to various reactions in the brain, ranging from neuronal necrosis and glial cell activation to focal structural disorganization. Furthermore, increased hippocampal neurogenesis has been documented in rodent models of acute convulsions. This is a report of hippocampal neurogenesis in a dog with spontaneous epileptic seizures. A 16-week-old epileptic German Shepherd Dog had marked neuronal cell proliferation (up to 5 mitotic figures per high-power field and increased immunohistochemical expression of proliferative cell nuclear antigen) in the dentate gyrus accompanied by microglial and astroglial activation. Some granule cells expressed doublecortin, a marker of immature neurons; mitotically active cells expressed neuronal nuclear antigen. No mitotic figures were found in the brain of age-matched control dogs. Whether increased neurogenesis represents a general reaction pattern of young epileptic dogs should be investigated.