Correction of metabolic acidosis in diarrheal calves by oral administration of electrolyte solutions with or without bicarbonate

Acid-base balance was evaluated in calves with experimentally induced viral diarrhea. When blood pH decreased to less than 7.200, calves were assigned to treatment groups and fed milk replacer, electrolyte solution without bicarbonate, or electrolyte solution containing bicarbonate. Calves in the electrolyte treatment groups had lower mortality (P less than 0.05), were better hydrated (P less than 0.05), and were less acidotic (P less than 0.05) than calves fed milk replacer. Bicarbonate-containing electrolyte solution restored acid-base balance (P less than 0.05) and corrected depression better (P less than 0.05) than electrolyte solution that did not contain bicarbonate. Both electrolyte solutions were equally good at correcting dehydration.     

Comparison of surgical versus medical treatment of nephrosplenic entrapment of the large colon in horses: 19 cases (1992-2002)

OBJECTIVE: To compare the outcome of horses with nephrosplenic entrapment of the large colon (NSELC) treated surgically or medically by rolling, administration of phenylephrine hydrochloride (or both), and exercise. DESIGN: Retrospective study. ANIMALS: 11 medically treated horses and 8 surgically treated horses with NSELC. PROCEDURE: Medical records of horses with nephrosplenic entrapment between 1992 and 2002 were reviewed. Medically treated horses were included if diagnosis and outcome of treatment of nephrosplenic entrapment were confirmed via transrectal examination and ultrasonographic examination. Surgically treated horses were included if the diagnosis was confirmed by exploratory laparotomy. Horses in which the large colon was entrapped between the spleen and body wall were not included. RESULTS: Significant differences in mean age, heart rate, and duration of colic prior to treatment were not detected between horses treated surgically or medically. Ten medically treated horses recovered without complications, and 1 died. In the surgically treated group, 6 of 8 horses recovered without complications and 2 died. Mortality rate did not differ between treatments. Duration of hospitalization for medically treated horses was significantly shorter and the cost significantly less than for surgically treated horses. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that medical treatment of horses with NSELC via administration of phenylephrine hydro-chloride, rolling during general anesthesia, or both appears to be as effective as and less expensive than surgical treatment.     

Canine coronavirus in Australian dogs

OBJECTIVE: To estimate the frequency of serum antibodies (IgG and IgM) to canine coronavirus (CCV) in the Australian dog population and evaluate the role of CCV as a causative agent of gastroenteritis. DESIGN: A serological survey of antibodies to CCV among different dog populations. PROCEDURE: The development and characterisation of an indirect ELISA for the detection of antibodies (IgG and IgM) to CCV was undertaken. Sera collected from both diarrhoeal and non-diarrhoeal dogs from various populations throughout Australia were tested for these antibodies to CCV. RESULTS: Serum samples (1396) collected from 1984 to 1998 were tested for the presence of IgG antibodies to CCV. Samples were divided into two categories on the basis of the number of dogs housed together. The groups were either an open population containing dogs housed as groups of three or less, or kennel populations. Sera from 15.8% of the open population and 40.8% of kennelled dogs were positive for CCV antibodies. The prevalence of antibodies varied from zero to 76% in kennelled dogs. About 23% of 128 dogs positive for IgG antibodies to CCV were also positive for IgM antibodies to CCV, indicating recent CCV infection. Of those dogs that were presented with clinical signs of gastroenteritis such as diarrhoea and vomiting (n = 29), 85% were positive in the IgM ELISA and 85.7% in the IgG ELISA for antibodies to CCV. In comparison, for those dogs presented without any history of gastroenteritis only 15% were positive for IgM and 30% positive for IgG. CONCLUSION: Serological evidence indicates that infection with CCV in dogs is widespread throughout the Australian mainland. The prevalence of antibodies varies greatly among different populations, with an average of 40.8% positive in kennelled populations and 15.8% in the open population.     

Use of electromyography for the diagnosis of equine hyperkalemic periodic paresis.

The use of electromyography (EMG) as a diagnostic aid for equine hyperkalemic periodic paresis (EHPP) was investigated in seven affected and seven control horses. Affected horses were confirmed positive for EHPP either by elevated serum potassium concentration with clinical signs of myotonia, or by inducing hyperkalemia and clinical signs using oral potassium chloride challenge. All horses were asymptomatic at the time EMG was performed, using bipolar fine wire needle electrodes. The myopotentials were recorded on magnetic tape and displayed on paper charts for analysis. Insertional and resting activity were recorded from the right supraspinatus, triceps, extensor carpi radialis and gluteal muscles in standing horses. Myotonic discharges were seen in six of seven affected horses but not in any of the controls. All seven affected horses and two control horses had prolonged insertional activity. Five out of seven affected horses and one control horse displayed spontaneous motor unit discharges unrelated to recording electrode movement. Myoelectrical potentials containing closely timed muscle potentials, i.e. doublets, were found in all affected horses, with four of seven affected horses also showing triplets. These potentials were not observed in any of the controls. No obvious difference in activity was observed among the four muscle sites tested. It is concluded that EMG is a safe and useful tool for diagnosing EHPP in horses not currently displaying clinical signs. Myotonic discharges and doublets appear to be the most diagnostically significant electromyographic abnormalities in EHPP affected horses.     

An immunohistochemical study of canine disseminated aspergillosis

An immunohistochemical study of 25 lesions from 7 dogs with disseminated aspergillosis (Aspergillus terreus) is presented. All had multiple fungal granulomas in many viscera, with centres of necrotic tissue and hyphal elements surrounded by a mixed infiltrate of predominantly mononuclear cells. Within these lesions, hyphae coated with immunoglobulin (IgG, IgM, IgA) and complement (C3, C4) were identified, together with peri-lesional mononuclear cells that reacted with antisera directed towards either IgG, IgM, IgA or a T lymphocyte marker (MUII). A conspicuous feature was the prominent hyphal fluorescence seen with IgA and C3 antisera. The IgA reagent also marked large numbers of mononuclear cells both around lesions and scattered throughout interstitial tissue, suggesting an abnormality of IgA production or regulation as a factor predisposing to this condition.     

The pathogenesis of the nervous syndrome of Phalaris aquatica toxicity in sheep

The clinical signs displayed by 96 sheep affected by the nervous syndrome of Phalaris aquatica toxicity and 10 normal sheep injected intravenously with the phalaris alkaloid, 5-methoxy dimethyltryptamine (dose range 0.01 to 5.0 mg/kg), were observed. The distributions of phalaris indole-like cytoplasmic pigments in nuclei of the brains and spinal cords of 9 naturally affected sheep were determined microscopically. Based on the relationship between clinical signs and the central nervous system nuclei involved in their production, the distribution of phalaris indole-like pigments, and the pharmacology of dimethylated tryptamines, it is suggested that the nervous syndrome induced by Phalaris aquatica results from a direct action of phalaris alkaloids upon serotonergic receptors in specific brain and spinal cord nuclei.     

Selenium supplementation affects broiler growth performance, meat yield and feather coverage

(1) Selenium (Se) is an essential part of numerous selenoproteins, most of which are involved in the antioxidant system of the body. It is also required by poultry for the maintenance of optimal health and meat quality. This paper reports data from a study examining the effect of dietary source and concentration of selenium on broiler performance and meat quality. (2) Increased dietary selenium content markedly reduced feed conversion ratio (FCR) as a result of significantly lower feed intakes of birds while maintaining the same weight gains. (3) Selenium supplementation increased feathering, with organic selenium (selenised yeast) being superior to inorganic selenium (sodium selenite). (4) Birds receiving organic selenium in their diets had improved eviscerated weight, breast yield and reduced drip loss. (5) There were significant concentration x source interactions on yields of breasts and marylands (thigh plus drumstick), with elevated levels of organic selenium increasing the yields, whereas the opposite was true for the inorganic selenium.     

Factors affecting the career path choices of graduates at the Western College of Veterinary Medicine

The objective of this study was to describe the demographics of the Class of 2006, Western College of Veterinary Medicine, and to determine which factors influenced the graduates' career path choices. Data were collected via an on-line survey and the response rate was 95.7% (67/70). The majority (57%) of graduates were starting their veterinary career in a food animal-related (FAR) job. Two factors were significantly associated with this choice: 1) those raised in, or near, a small center (population < 10 000) were 3.4 times (P = 0.03) more likely to accept a FAR position than were those raised in a large center (> 10 000), and 2) graduates with a bachelor of science in agriculture (BSc Ag) were 4.5 times (P = 0.04) more likely to begin their career as a FAR practitioner than were those without such a degree. However, 9 of the 16 graduates having a BSc Ag had an urban upbringing.