Development and initial validation of a sensory threshold examination protocol (STEP) for phenotyping canine pain syndromes

Objective

To study the feasibility and test–retest repeatability of a sensory threshold examination protocol (STEP) and report the quantitative sensory threshold distributions in healthy dogs.

Sedative and antinociceptive effects of different combinations of detomidine and methadone in standing horses

Objective

To evaluate intravenous (IV) detomidine with methadone in horses to identify a combination which provides sedation and antinociception without adverse effects.

N dynamics and sources of N2O production following pig slurry application to a loamy soil

Carbon (C) and Nitrogen dynamics and sources of nitrous oxide (N₂O) production were investigated in a loamy soil amended with pig slurry. Pig slurry (40000kgha^–1) or distilled H₂O was applied to intact soil cores of the upper 5cm of a loamy soil which were incubated under aerobic conditions for 28 days at 25°C. Treatments were with or without acetylene (C₂H₂), which is assumed to inhibit the reduction of N₂O to dinitrogen (N₂), and with or without dicyandiamide (DCD), which is thought to inhibit nitrification. Volatilization of ammonia (NH₃), pH, carbon dioxide (CO₂) and N₂O production, and ammonium (NH₄ ⁺) and nitrate NO₃ ^–) concentrations were monitored. The pH of the pig slurry amended soil increased from an initial value of 7.1 to pH 8.3 within 3 days; it then decreased slowly but was still at a value of 7.4 after 28 days. Twenty percent of the NH₄ ⁺ applied volatilized within 28 days. Sixty percent of the C applied in the pig slurry evolved as CO₂, if no priming effect was assumed, but only 38% evolved when the soil was amended with DCD. Pig slurry significantly increased denitrification and the ratio between its gaseous products, N₂O and N₂, was 0.21. No significant increases in NO₃ ^– concentration occurred, and N₂O produced through nitrification was 0.07mg N₂O-N kg^–1 day^–1 or 33% of the total N₂O produced. C₂H₂ was used as a C substrate by microorganisms and increased the production of N₂O. Received: 12 May 1997     

Arthroscopic removal of axial osteochondral fragments of the proximoplantar aspect of the proximal phalanx using electrocautery probes in 23 standardbred racehorses

OBJECTIVES: To describe the outcome after arthroscopic electrosurgical excision of axial osteochondral (OC) fragments of the proximal plantar aspect of the 1st phalanx (P1) in horses. STUDY DESIGN: Retrospective study. POPULATION: Twenty-three Standardbred racehorses. METHODS: Medical records of Standardbred racehorses that had arthroscopic dissection of axial OC fragments of the proximal plantar aspect of P1 with electrocautery probes were reviewed. Horses were positioned in dorsal recumbency; a 1.5% glycine solution was used to maintain joint distension. The arthroscope portal was in the proximal plantar joint pouch and OC fragments were approached using either an ipsilateral or a contralateral triangulation technique. Dissection of the fibrous attachments was performed using loop and hook electrocautery probes. Follow-up was obtained by telephone questionnaire of owners or trainers and examination of race summary records. RESULTS: Thirty-three axial OC fragments were removed from 28 metatarsophalangeal joints (left, 14; right, 14). No major operative or postoperative complications occurred. Seven of 8 (79%) of horses that raced before surgery raced after surgery. Thirty-six percent (n=4) of horses that had not raced before surgery raced after surgery. CONCLUSION: Intra-articular electrosurgery is a safe, easy alternative to conventional excision of axial OC fragments of the proximal plantar aspect of P1. CLINICAL RELEVANCE: Arthroscopic excision using electrocautery probes is a valid alternate method for removal of axial OC fragments of the proximal plantar aspect of P1. In addition, the dorsal recumbency position facilitates removal of several fragments and multiple joint surgery.     

Comparison of two laparoscopic treatments for experimentally induced abdominal adhesions in pony foals

OBJECTIVE: To compare laparoscopic dissection with-laparoscopic dissection combined with abdominal instillation of ferric hyaluronate gel for the treatment of experimentally induced adhesions in pony foals. ANIMALS: 12 healthy pony foals. PROCEDURE: A serosal abrasion method was used to create adhesions at 4 sites on the jejunum (day 0). At day 7 laparoscopy was performed and the adhesions observed in each foal were recorded. In group-1 foals (n = 6), the adhesions were separated laparoscopically (treatment 1). In group-2 foals (n = 6), 300 mL of 0.5% ferric hyaluronate gel was infused into the abdomen after the adhesions were separated laparoscopically (treatment 2). At day 24, terminal laparoscopy was performed and the adhesions observed were recorded. Total number of adhesions within each group was compared between day 7 and 24. Data were analyzed to determine whether an association existed between the number of adhesions on day 24 and treatment type. RESULTS: At day 24, the number of adhesions was significantly decreased within each group, compared with the number of adhesions at day 7 (group-1 foals, 10 vs 22 adhesions; group-2 foals, 3 vs 20 adhesions). Treatment 1 was associated with a significantly higher number of adhesions at day 24, compared with treatment 2 (odds ratio, 4.54; 95% confidence interval, 1.03 to 23.02). CONCLUSION AND CLINICAL RELEVANCE: Abdominal instillation of 0.5% ferric hyaluronate gel after laparoscopic dissection was a more effective technique than laparoscopic dissection alone to treat experimentally induced adhesions in pony foals. Laparoscopic adhesiolysis following abdominal surgery in foals is a safe and effective technique.     

Population variability in animal health: Influence on dose‐exposure‐response relationships: Part II: Modelling and simulation

During the 2017 Biennial meeting, the American Academy of Veterinary Pharmacology and Therapeutics hosted a 1‐day session on the influence of population variability on dose‐exposure‐response relationships. In Part I, we highlighted some of the sources of population variability. Part II provides a summary of discussions on modelling and simulation tools that utilize existing pharmacokinetic data, can integrate drug physicochemical characteristics with species physiological characteristics and dosing information or that combine observed with predicted and in vitro information to explore and describe sources of variability that may influence the safe and effective use of veterinary pharmaceuticals.     

Comparative Analysis of the Cytotoxic Effects of Okadaic Acid-Group Toxins on Human Intestinal Cell Lines

The phycotoxin, okadaic acid (OA) and dinophysistoxin 1 and 2 (DTX-1 and -2) are protein phosphatase PP2A and PP1 inhibitors involved in diarrhetic shellfish poisoning (DSP). Data on the toxicity of the OA-group toxins show some differences with respect to the in vivo acute toxicity between the toxin members. In order to investigate whether OA and congeners DTX-1 and -2 may induce different mechanisms of action during acute toxicity on the human intestine, we compared their toxicological effects in two in vitro intestinal cell models: the colorectal adenocarcinoma cell line, Caco-2, and the intestinal muco-secreting cell line, HT29-MTX. Using a high content analysis approach, we evaluated various cytotoxicity parameters, including apoptosis (caspase-3 activation), DNA damage (phosphorylation of histone H2AX), inflammation (translocation of NF-κB) and cell proliferation (Ki-67 production). Investigation of the kinetics of the cellular responses demonstrated that the three toxins induced a pro-inflammatory response followed by cell cycle disruption in both cell lines, leading to apoptosis. Our results demonstrate that the three toxins induce similar effects, as no major differences in the cytotoxic responses could be detected. However DTX-1 induced cytotoxic effects at five-fold lower concentrations than for OA and DTX-2.     

Ventral laparoscopic abomasopexy on adult cows

Displacement of the abomasum is frequently diagnosed by veterinarians in bovine practice and numerous surgical techniques have been developed to treat and prevent this condition. Complications secondary to those techniques are related to their degree of invasiveness and the development of postoperative wound infections. The objectives of this study were to describe a safe and reliable abomasopexy technique by laparoscopy and to assess postoperative adhesion formation. A ventral laparoscopic abomasopexy was performed on 10 adult dry cows. The abomasum was fixed with 4 simple interrupted sutures using USP 2 polydioxanone suture material. No major complications were encountered during the surgery. Abomasal adhesions were visually evaluated by laparoscopy 3 mo postoperatively. This technique proved to be simple and safe, and it provided adequate abomasum fixation in healthy dry cows. It could be used to surgically correct left displaced abomasum.