Proposed Canadian Consensus Guidelines on Osteoarthritis Treatment Based on OA-COAST Stages 1-4.

The Canadian consensus guidelines on OA treatment were created from a diverse group of experts, with a strong clinical and/or academic background in treating OA in dogs. The document is a summary of the treatment recommendations made by the group, with treatments being divided into either a core or secondary recommendation. Each treatment or modality is then summarized in the context of available research based support and clinical experience, as the treatment of OA continues to be a multimodal and commonly a multidisciplinary as well as individualized approach. The guidelines aim to help clinicians by providing clear and clinically relevant information about treatment options based on COAST defined OA stages 1-4.

Management of veterinary anaesthesia and analgesia in small animals: A survey of English-speaking practitioners in Canada.

OBJECTIVE: To describe how small animal anaesthesia and analgesia is performed in English-speaking Canada, document any variation among practices especially in relation to practice type and veterinarian's experience and compare results to published guidelines. DESIGN: Observational study, electronic survey. SAMPLE: 126 respondents. PROCEDURE: A questionnaire was designed to assess current small animal anaesthesia and analgesia practices in English-speaking Canadian provinces, mainly in Ontario, Alberta and British Columbia. The questionnaire was available through SurveyMonkey® and included four parts: demographic information about the veterinarians surveyed, evaluation and management of anaesthetic risk, anaesthesia procedure, monitoring and safety. Year of graduation and type of practice were evaluated as potential risk factors. Exact chi-square tests were used to study the association between risk factors and the association between risk factors and survey responses. For ordinal data, the Mantel-Haenszel test was used instead. RESULTS: Response rate over a period of 3 months was 12.4% (126 respondents out of 1 016 invitations). Current anaesthesia and analgesia management failed to meet international guidelines for a sizable number of participants, notably regarding patient evaluation and preparation, safety and monitoring. Nearly one third of the participants still consider analgesia as optional for routine surgeries. Referral centres tend to follow guidelines more accurately and are better equipped than general practices. CONCLUSIONS AND CLINICAL RELEVANCE: A proportion of surveyed Canadian English-speaking general practitioners do not follow current small animal anaesthesia and analgesia guidelines, but practitioners working in referral centres are closer to meet these recommendations.

Total Intravenous Anaesthesia with Ketamine, Medetomidine and Midazolam as Part of a Balanced Anaesthesia Technique in Horses Undergoing Castration.

To evaluate the use of ketamine-medetomidine-midazolam total intravenous infusion as part of a balanced anaesthetic technique for surgical castration in horses. Five healthy Standardbred cross colts were premedicated with IV acepromazine (0.01-0.02 mg/kg), medetomidine (7 µg/kg) and methadone (0.1 mg/kg) and anaesthesia induced with IV ketamine (2.2 mg/kg) and midazolam (0.06 mg/kg). Horses were anaesthetised for 40 min with an IV infusion of ketamine (3 mg/kg/h), medetomidine (5 µg/kg/h) and midazolam (0.1 mg/kg/h) while routine surgical castration was performed. Cardiorespiratory variables, arterial blood gases, and anaesthetic depth were assessed at 5 to 10 min intervals. Post-anaesthesia recovery times were recorded, and the quality of the recovery period was assessed. The anaesthetic period and surgical conditions were acceptable with good muscle relaxation and no additional anaesthetic required. The median (range) time from cessation of the infusion to endotracheal tube extubation, head lift and sternal recumbency were 17.2 (7-35) min, 25 (18.9-53) min and 28.1 (23-54) min, respectively. The quality of anaesthetic recovery was good, with horses standing 31.9 (28-61) min after the infusion was ceased. During anaesthesia, physiological variables, presented as a range of median values for each time point were: heart rate 37-44 beats/min, mean arterial pressure 107-119 mmHg, respiratory rate 6-13 breaths/min, arterial partial pressure of oxygen 88-126 mmHg, arterial partial pressure of carbon dioxide 52-57 mmHg and pH 7.36-7.39. In conclusion, the co-administration of midazolam, ketamine and medetomidine as in IV infusion, when used as part of a balanced anaesthetic technique, was suitable for short term anaesthesia in horses undergoing castration.

Management of veterinary anaesthesia in small animals: A survey of current practice in Quebec.

OBJECTIVE: To describe how small animal anaesthesia is performed in French-speaking Eastern Canada, and the variations between practices, in particular based on practice type, veterinarian gender and experience. DESIGN: Observational study, survey. SAMPLE: 156 respondents. PROCEDURE: A questionnaire was designed to assess current small animal anaesthesia practices in French-speaking Eastern Canada, mainly in the province of Quebec. The questionnaire was available through SurveyMonkey, and consisted of four parts: demographic information about the veterinarians surveyed, evaluation and management of anaesthetic risk, anaesthesia procedure, monitoring and safety. Gender, year of graduation, and type of practice were tested as potential risk factors. Chi-square exact test was used to study relations between each risk factor, and the effect of the selected risk factor on each response of the survey. For ordinal data, the Cochran-Mantel-Haenszel test was used to maximize power. RESULTS: Response rate over a period of 3 months was 20.85% (156 respondents). Overall, the way anaesthesia is performed by most respondents does not meet international guidelines, such as patient preparation and evaluation prior to anaesthesia, not using individualised protocols (for 41%), not obtaining intravenous access (12.4% use it for all their anaesthesia in cats, and 30.6% in dogs), lack of patient monitoring at certain intervals for 55% of the responses, and client prompted optional analgesia (for 29% of respondents). Some practices are more compliant than others. Among them, referral centres generally offer better care than general practices. CONCLUSIONS AND CLINICAL RELEVANCE: The level of care in anaesthesia and analgesia in practices in French-speaking Eastern Canada is concerning, highlighting the need for more sustained continuing education.

The toxin MPTP generates similar cognitive and locomotor deficits in hTau and tau knock-out mice.

Parkinson's disease (PD) is characterized by motor deficits, although cognitive disturbances are frequent and have been noted early in the disease. The main pathological characteristics of PD are the loss of dopaminergic neurons and the presence of aggregated α-synuclein in Lewy bodies of surviving cells. Studies have also documented the presence of other proteins within Lewy bodies, particularly tau, a microtubule-associated protein implicated in a wide range of neurodegenerative diseases, including Alzheimer's disease (AD). In AD, tau pathology correlates with cognitive dysfunction, and tau mutations have been reported to lead to dementia associated with parkinsonism. However, the role of tau in PD pathogenesis remains unclear. To address this question, we induced parkinsonism by injecting the toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in hTau mice, a mouse model of tauopathy expressing human tau, and a mouse model knock-out for tau (TKO). We found that although MPTP impaired locomotion (gait analysis) and cognition (Barnes maze), there were no discernable differences between hTau and TKO mice. MPTP also induced a slight but significant increase in tau phosphorylation (Thr205) in the hippocampus of hTau mice, as well as a significant decrease in the soluble and insoluble tau fractions that correlated with the loss of dopaminergic neurons in the brainstem. Overall, our findings suggest that, although MPTP can induce an increase in tau phosphorylation at specific epitopes, tau does not seem to causally contribute to cognitive and locomotor deficits induced by this toxin.

Use of a novel surgical approach for treatment of complete bilateral membranous choanal atresia in an alpaca cria.

CASE DESCRIPTION A 4-hour-old 6.3-kg (13.9-lb) female alpaca cria was evaluated because of severe respiratory distress and difficulty nursing since birth. CLINICAL FINDINGS The cria had open-mouth breathing and cyanotic membranes, with no airflow evident from either nostril. Supplemental oxygen was delivered, and the patient was anesthetized and intubated orotracheally; a CT evaluation of the head confirmed bilateral membranous obstruction of the nasal cavities, consistent with complete bilateral choanal atresia. TREATMENT AND OUTCOME Choanal atresia was treated with an endoscopically assisted balloon-dilation technique, and temporary tracheostomy was performed. Stenosis recurred, requiring revision of the repair and intranasal stent placement 3 days after the first surgery. The tracheostomy tube was removed the next day. Complications during hospitalization included mucoid obstruction of the tracheostomy tube, granulation tissue development in the trachea near the tracheostomy site, mucoid stent obstruction, aspiration pneumonia, and presumed partial failure of passive transfer of immunity. The stents were removed 2 weeks after admission, and the cria was discharged 3 days later. The owner was advised that the animal should not be bred. At last follow-up 3 years later, the alpaca was doing well. CLINICAL RELEVANCE Surgical treatment with a balloon-dilation technique and placement of nasal stents with endoscopic guidance were curative in this neonatal alpaca with bilateral membranous choanal atresia. Computed tomography was useful to determine the nature of the atresia and aid surgical planning. Because a genetic component is likely, owners should be advised to prevent affected animals from breeding.

Effects of isoflurane on somatosensory-evoked potentials in calves: a pilot study.

Somatosensory evoked potentials (SSEP) are used to monitor sensory function and are often recorded under general anesthesia. The objective of the study was to evaluate the effects of isoflurane on SSEPs in calves as it has not been reported. Eight calves (mean age: 40 days), were included in the study. Calves were anesthetized with a randomized sequence of four different isoflurane partial pressures. Blood gas analysis was performed before each measurement. SSEP were induced by repeated stimulation of the common dorsal digital nerve III. SSEPs were recorded from the lumbo-sacral junction (s-SSEP) and the head (c-SSEP). Latency and inter-amplitude of each peak were measured. For s-SSEP: One negative (Nsp1) and two positive (Psp1 and Psp2) peaks were identified in all tracings except for two calves. There was a significant effect of isoflurane on the latency of Psp2 (P = 0.01). Inter-amplitude decreased significantly with PaO2, PaCO2 and temperature (P < 0.05). Psp2 latency decreased with PaO2 (P = 0.01). For c-SSEP: two positive (Pc1 and Pc2) and two negative (Nc1 and Nc2) peaks were identified. There were identifiable peaks for the analysis of Pc1 latencies only. There was a significant positive linear relation between end-tidal isoflurane partial pressure (ETiso) and Pc1 latency (P = 0.04). None of the co-variables had a significant effect on the latency of Pc1 (P > 0.1). Isoflurane has a major impact on the recording of c-SSEP. Recording should be done at the lowest ETiso as possible, and anesthesia parameters should be kept constant.

Les potentiels évoqués somesthésiques (SSEP) sont utilisés pour monitorer les fonctions sensorielles et sont souvent enregistrées sous anesthésie générale. L'objectif de la présente étude était d'évaluer les effets de l'isoflurane sur les SSEPs de veaux étant donné qu'aucune donnée n'a été rapportée pour cette espèce. Huit veaux (âge moyen : 40 jours) furent inclus dans l'étude. Les veaux furent anesthésiés avec quatre pressions partielles d'isoflurane selon une séquence randomisée. L'analyse des gaz sanguins fut effectuée avant chaque mesure. Les SSEP furent induits par stimulation répétée du nerf digital dorsal commun III. Les SSEPs étaient enregistrés à la jonction lombosacrée (s-SSEP) et à la tête (c-SSEP). La latence et l'inter-amplitude de chaque pic furent mesurées. Pour le s-SSEP : un pic négatif (Nsp1) et deux pics positifs (Psp1 et Psp2) furent identifiés dans tous les tracés sauf pour deux veaux. L'isoflurane avait un effet significatif sur la latence de Psp2 (P = 0,01). L'inter-amplitude a diminué significativement avec PaO2, PaCO2 et la température (P < 0,05). La latence de Psp2 diminuait avec PaO2 (P = 0,01). Pour c-SSEP : deux pics positifs (Pc1 et Pc2) et deux pics négatifs (Nc1 et Nc2) furent identifiés. Il y avait des pics identifiables uniquement pour l'analyse de la latence de Pc1. Il y avait une relation linéaire positive significative entre la pression partielle d'isoflurane en fin d'expiration (ETiso) et la latence de Pc1 (P = 0,04). Aucune des co-variables n'avait un effet significatif sur la latence de Pc1 (P > 0,1). L'isoflurane avait un impact majeur sur l'enregistrement de c-SSEP. L'enregistrement devrait être fait avec le ETiso le plus bas faible possible, et les paramètres d'anesthésie devraient être gardés constants.(Traduit par Docteur Serge Messier).

Dexmedetomidine increases tau phosphorylation under normothermic conditions in vivo and in vitro.

There is developing interest in the potential association between anesthesia and the onset and progression of Alzheimer's disease. Several anesthetics have, thus, been demonstrated to induce tau hyperphosphorylation, an effect mostly mediated by anesthesia-induced hypothermia. Here, we tested the hypothesis that acute normothermic administration of dexmedetomidine (Dex), an intravenous sedative used in intensive care units, would result in tau hyperphosphorylation in vivo and in vitro. When administered to nontransgenic mice, Dex-induced tau hyperphosphorylation persisting up to 6 hours in the hippocampus for the AT8 epitope. Pretreatment with atipamezole, a highly specific α2-adrenergic receptor antagonist, blocked Dex-induced tau hyperphosphorylation. Furthermore, Dex dose-dependently increased tau phosphorylation at AT8 in SH-SY5Y cells, impaired mice spatial memory in the Barnes maze and promoted tau hyperphosphorylation and aggregation in transgenic hTau mice. These findings suggest that Dex: (1) increases tau phosphorylation, in vivo and in vitro, in the absence of anesthetic-induced hypothermia and through α2-adrenergic receptor activation, (2) promotes tau aggregation in a mouse model of tauopathy, and (3) impacts spatial reference memory.

Efficacy of extended intramammary ceftiofur therapy against mild to moderate clinical mastitis in Holstein dairy cows: a randomized clinical trial.

Few studies have investigated the efficacy of extended ceftiofur therapy and none have focused on extended therapy for naturally occurring clinical mastitis. The objective of this study was to compare the efficacy of extended intramammary ceftiofur therapy of 8 d duration with a standard 2-day regimen for the treatment of naturally occurring mild to moderate clinical mastitis in lactating dairy cows. Holstein cows from 22 dairy herds (n = 241) were randomly allocated to the 2 treatment groups. For each case of mastitis, 125 mg of ceftiofur hydrochloride was administered intramammary once a day for 2 or 8 d. Clinical cure, 21 d after the last treatment, was 89% (98/110) in each group. Bacteriological cure 21 d after the last treatment for the 2- and 8-day regimens were 32% (15/47) and 61% (25/41), respectively, for all bacteria (P = 0.007), 64% (9/14) and 82% (9/11), respectively, for streptococci (P = 0.50), and 0% (0/20) and 47% (9/19), respectively, for Staphylococcus aureus (P = 0.0004). There were no statistical differences between groups for new intramammary infections. Overall, ceftiofur extended therapy increased cure when compared to a 2-day regimen for the treatment of naturally occurring mild to moderate clinical mastitis in lactating dairy cows.

Peu d'études ont investigué l'efficacité d'une thérapie prolongée avec du ceftiofur et aucune n'a examiné attentivement une thérapie prolongée dans le cas de mammite clinique se produisant naturellement. L'objectif de la présente étude était de comparer l'efficacité d'une thérapie intra-mammaire prolongée d'une durée de 8 jours avec du ceftiofur à la thérapie standard de 2 jours pour le traitement de mammite clinique légère à modérée survenant naturellement chez des vaches laitières en lactation. Des vaches de race Holstein provenant de 22 troupeaux laitiers (n = 241) ont été réparties de manière aléatoire dans les 2 groupes de traitement. Pour chaque cas de mammite, 125 mg d'hydrochlorure de ceftiofur furent administrés par voie intra-mammaire une fois par jour pour 2 ou 8 jours. La guérison clinique, 21 jours après le dernier traitement, était de 89 % (98/110) dans chaque groupe. La guérison bactériologique 21 jours après le dernier traitement pour les groupes 2 et 8 jours était respectivement 32 % (15/47) et 61 % (25/41) pour toutes les bactéries (P = 0,007), 64 % (9/14) et 82 % (9/11), respectivement, pour les streptocoques (P = 0,50) et 0 % (0/20) et 47 % (9/19), respectivement pour Staphylococcus aureus (P = 0,0004). Il n'y avait aucune différence statistiquement significative entre les groupes pour les nouvelles infections intra-mammaires. Globalement, une thérapie prolongée au ceftiofur augmenta la guérison lorsque comparée à une thérapie de 2 jours pour le traitement de mammite clinique légère à modérée survenant naturellement chez les vaches laitières en lactation.(Traduit par Docteur Serge Messier).

Respiratory mechanics: comparison of Beagle dogs, Göttingen minipigs and Cynomolgus monkeys.

INTRODUCTION: When the no observed adverse effect level (NOAEL) is determined by respiratory safety pharmacology, follow-up studies are warranted and may include airway resistance and compliance. Respiratory mechanics in commonly used large animal species (Beagle dogs, Cynomolgus monkeys, and Göttingen minipigs) were compared. METHODS: Eighteen animals were used (3/sex/species) in an anesthetized model (propofol infusion) with pancuronium as a neuromuscular blocker. Parameters of respiratory mechanics were evaluated at baseline and at peak drug effect. Resistance (Rrs) and elastance (Ers) were measured by applying a single frequency forced oscillation (0.5 Hz) to the subject's airway opening and fitting the flow, volume and pressure data to the single compartment model of the lung. Increasing doses of intravenous (IV) methacholine were administered in all three species, as well as doubling aerosolized concentrations of the same bronchoconstrictor agent before and after inhaled albuterol. RESULTS: The slope of the IV methacholine dose-response curve for Rrs was similar in dogs and monkeys and both species differed from minipigs, which showed greater reactivity. At the highest IV dose tested, minipigs also reached higher levels of bronchoconstriction than the other two species. They were followed, in decreasing order, by dogs and monkeys. Albuterol induced a significant decrease in the slope of the dose-response curve only in dogs and monkeys. DISCUSSION: Scientific literature is available on respiratory mechanics in monkeys and dogs but not in minipigs. Our results suggest that minipigs were more reactive than dogs and monkeys to IV methacholine while less sensitive to inhaled albuterol.