The detection of infectious pancreatic necrosis virus in asymptomatic carrier fish by an integrated cell-culture and ELISA technique

Abstract. The need to accurately, reliably and economically screen large populations of brood salmon for infectious pancreatic necrosis virus (IPNV) prompted a fresh approach to the use of ELISA and cell cultures. The result is an integrated procedure that recognizes the limitations of each method while building upon the strength of both in the way that they are brought together, ELISA tests can never be sensitive enough to detect the very low virus levels typical of carrier fish, but are able to detect virus in infected cell cultures, both specifically and objectively. Cell cultures provide the means to detect very low virus levels, but without specificity and only through subjective observation. Without a suitable ELISA, the need to keep cell monolayers in a condition in which viral effects can be observed imposes strict demands on inoculation and culture procedures. In contrast, the new procedure described in this paper provides a simpler culture method in which the inoculum is retained throughout a single, uninterrupted 14-day culture cycle. This culture duration allowed maximum opportunity for viral replication in healthy cells, even though the monolayers became disorganized. However, the cultures were tested in the standardized ELISA, eliminating the need for microscopic observation and virus neutralization tests. Thorough validation studies confirmed the system's adequacy in practice.     

Return to use and performance following exploratory celiotomy for colic in horses: 195 cases (2003–2010)

Reasons for performing study: There are few objective data on return to use and performance in horses following colic surgery. Objective: To investigate return to functional use of horses following colic surgery and factors associated with a negative outcome. Methods: The North Carolina State University Equine Colic Database was reviewed for horses that underwent exploratory celiotomy for colic (2003–2010). Horses were excluded from the study if they survived <6 months, had no intended use preoperatively, or if further data were not available at attempted follow‐up. Information retrieved included history, background, use, and selected pre‐, intra‐, and post operative factors. Telephone interviews were used to obtain follow‐up data. Logistic regression was used to investigate associations between clinical data and outcome, reported as odds ratios with a 95% confidence interval and corresponding P value. Results: Of patients surviving to 6 months, 133/195 (68%) were performing their intended use and 85/156 (54%) were at or above preoperative performance. At one year, 145/190 (76%) horses were performing their intended use and 101/153 (66%) were at or above preoperative performance. Animals were significantly less likely to return to use/performance if they had a previous celiotomy, stall rest for an orthopaedic condition, a nonstrangulating lesion type, incisional hernia, diarrhoea or laminitis. Conclusions: The overall prognosis for return to use and performance following colic surgery is fair to good. Multiple pre‐ and post operative factors may affect the likelihood of return to use and performance. Potential relevance: Targeted owner education regarding preoperative lameness, post operative rehabilitation and treatment for complications, such as incisional hernioplasty, may help inform owners about their horse's potential for return to use and performance following colic surgery.     

Pharmacokinetics of carbetocin,a long‐acting oxytocin analogue,following intravenous administration in horses

Reason for performing study: Current therapy protocols to treat persistent post mating endometritis and retained fetal membranes in mares typically include the administration of ecbolic drugs. Evaluation of the pharmacokinetics and tolerability of carbetocin, a long‐acting oxytocin analogue, after i.v. administration is required. Objectives: To determine the pharmacokinetic parameters (principally half‐life) of carbetocin in horses. Methods: Five mature mares and one gelding received 0.175 mg carbetocin i.v. All animals were monitored periodically throughout the study for elevation in rectal temperature, heart rate, respiratory rate and signs of pain or discomfort. Plasma samples were collected for determination of carbetocin concentrations by radioimmunoassay. Results: Administration of carbetocin was well tolerated by all horses and its half‐life was 17.2 min. Conclusions: The half‐life of carbetocin is greater than that previously reported for oxytocin (6.8 min). Potential relevance: Carbetocin is an attractive alternative to oxytocin therapy in broodmare management.     

Ocular toxicity and distribution of subconjunctival and intravitreal rapamycin in horses

In vitro photosensitivity of rapamycin (RAPA) and ocular toxicity and distribution of intravitreal and subconjunctival RAPA was evaluated in normal horses. RAPA (2.5 mg, 5 mg, and 10 mg) was placed in 10 mL of PBS and maintained in a water bath at 37 °C, kept in the dark or subjected to room light, and sampled for up to 3 months for RAPA levels. Six normal adult horses received either 5 mg (n = 2) or 10 mg (n = 2) of RAPA intravitreally or 10 mg (n = 2) subconjunctivally. Ophthalmic exams and electroretinography (ERG) were performed prior to injection and on days 1, 7, 14, and 21 post‐injection. Eyes were enucleated and samples were collected for RAPA concentrations and histopathology. No difference in light vs. dark RAPA concentrations was observed, suggesting a lack of RAPA phototoxicity. No evidence of ocular toxicity was noted on ophthalmic examination or histopathology. RAPA was not detected intraocularly 7 days post‐injection in eyes receiving subconjunctival RAPA, but was detected in the vitreous at 21 days post‐injection. Drug could be detected in both the aqueous and vitreous humor after intravitreal injection. Further study is needed to determine the efficacy of intravitreal RAPA.     

Azoturia in a Greyhound: clinical pathology aids to diagnosis

A provisional diagnosis of azoturia and/or haematuria was made in a Greyhound. This condition was differentiated from the syndromes of acute abdominal accident, acute nephritis, cystitis and spinal pressure on sensory nerves by means of the clinical pathology aids of biochemistry, serum enzymology, haematology and urine analysis and the physical aid of X-ray and ECGT. The results indicated that the animal was suffering from acute azoturia.
Résumé. Un cas d'azoturie et/ou hématurie fut diagnostiquée comme probable chez un Lévrier. Cet état fut différencié des syndromes de troubles abdominaux accidentels aigus, de néephrite aiguë, de cystite, et de pression spinale sur les nerfs sensoriels, au moyen des aides procurées à la pathologie clinique par la biochimie, la séroenzymologie, l'hématologie et les analyses d'urine, et avec l'aide de la physique, par Rayons-X et électro-encéphalographie. Les résultats indiquèrent que l'animal souffrait d'une azoturie aiguë.
Zusammenfassung. Eine Wahrscheinlichkeits-Diagnose der Azoturie und/oder Blutharnen, wurde im Windhund vorgenommen. Diese Kondition differenzierte sich den Syndromen von Bauchakzidenz, akuter Nierenentzündung, Blasenentzündung und Rückgratsdruck des Sinnesnerven durch physikalische Hilfe von Röntgenstrahlen und EEG. Das Untersuchungsergebniss deutete an, dass das Tier von akuter Azoturie litt.     

Experimental reproduction of viral chorioretinitis in kangaroos

OBJECTIVE: To investigate whether preparations containing Wallal and/or Warrego viruses could cause disease when inoculated subcutaneously into captive kangaroos. DESIGN AND PROCEDURE: Four groups of two kangaroos, seronegative to both Wallal and Warrego virus, were each inoculated with wild Wallal virus, cultured Wallal virus, wild Warrego virus, or wild Warrego virus followed by wild Wallal virus after 3 weeks. A single uninoculated animal served as a control. Animals were monitored weekly under anaesthesia, examined ophthalmoscopically (including fundic photography), and samples collected for haematological and serum biochemical analysis, virus isolation, PCR and serological examination for antibodies against Wallal and Warrego viruses. Animals inoculated with cultured Wallal virus were killed at week 10, and remaining kangaroos were reinoculated with cultured Wallal virus at week 12. RESULTS: Virus was isolated from the blood of two kangaroos 2 weeks after inoculation with Wallal virus preparations, and from a third kangaroo 2 weeks after reinoculation. By 3 weeks after inoculation, all kangaroos given Wallal virus preparations had seroconverted to Wallal virus and one had seroconverted to Warrego virus. Fundic changes were detected in the three viraemic kangaroos 4 or more weeks after inoculation, and lesions were present in the eye and brain typical of those seen in field cases of chorioretinitis. No other kangaroos had lesions. Wallal virus was identified by PCR and immunohistochemical analysis in the retina of one affected animal and orbivirus-like particles were seen by electron microscopy in the remains of retinal cells. CONCLUSION: The condition of chorioretinitis was reproduced in three of eight kangaroos by inoculation with preparations containing Wallal virus.