Search

Background Obesity is an important equine welfare issue. Whilst dietary restriction is the most effective weight-loss tool, individual animals range in their weight-loss propensity. Gastrointestinal-derived bacteria play a fundamental role in host-health and have been associated with obesity and weight-loss in other species. This study evaluated the faecal microbiome (next-generation sequencing of 16S rRNA genes) of 15 obese Welsh Mountain pony mares, in the same 11-week period across 2 years (n = 8 Year 1; n = 7 Year 2). Following a 4-week acclimation period (pre-diet phase) during which time individuals were fed the same hay to maintenance (2% body mass (BM) as daily dry matter (DM) intake), animals underwent a 7-week period of dietary restriction (1% BM hay as daily DM intake). Faeces were sampled on the final 3 days of the pre-diet phase and the final 3 days of the dietary restriction phase. Bacterial communities were determined using Next Generation Sequencing of amplified V1-V2 hypervariable regions of bacterial 16S rRNA. Results Losses in body mass ranged from 7.11 to 11.59%. Changes in the faecal microbiome composition following weight-loss included a reduction in the relative abundance of Firmicutes and Tenericutes and a reduction in indices of bacterial diversity. Pre-diet diversity was negatively associated with weight-loss. Pre-diet faecal acetate concentration was a strong predictor of subsequent weight-loss and negatively associated with Sphaerochaeta (Spirochaetes phylum) abundance. When animals were divided into 3 groups (high, mid, low) based overall weight loss, pre-diet bacterial community structure was found to have the greatest divergence between the high and low weight-loss groups (R = 0.67, p Conclusions Weight-loss in this group of ponies was associated with lower pre-diet faecal bacterial diversity and greater pre-diet acetate concentration. Overall, these data support a role for the faecal microbiome in weight-loss propensity in ponies and provide a baseline for research evaluating elements of the faecal microbiome in predicting weight-loss success in larger cohorts.

Bacteria residing in the gastrointestinal tract of mammals are crucial for the digestion of dietary nutrients. Bacterial community composition is modified by age and diet in other species. Although horses are adapted to consuming fibre-based diets, high-energy, often high-starch containing feeds are increasingly used. The current study assessed the impact of age on the faecal bacteriome of ponies transitioning from a hay-based diet to a high-starch diet. Over two years, 23 Welsh Section A pony mares were evaluated (Controls, 5–15 years, n = 6/year, 12 in total; Aged, ≥19 years, n = 6 Year 1; n = 5 Year 2, 11 in total). Across the same 30-week (May to November) period in each year, animals were randomly assigned to a 5-week period of study and were individually fed the same hay to maintenance (2% body mass as daily dry matter intake) for 4-weeks. During the final week, 2g starch per kg body mass (micronized steam-flaked barley) was incorporated into the diet (3-day transition and 5 days at maximum). Faecal samples were collected for 11 days (final 3 days hay and 8 days hay + barley feeding). Bacterial communities were determined using Ion Torrent Sequencing of amplified V1–V2 hypervariable regions of 16S rRNA. Age had a minimal effect on the bacteriome response to diet. The dietary transition increased Candidatus Saccharibacteria and Firmicutes phyla abundance and reduced Fibrobactres abundance. At the genera level, Streptococcus abundance was increased but not consistently across individual animals. Bacterial diversity was reduced during dietary transition in Streptococcus ‘responders’. Faecal pH and VFA concentrations were modified by diet but considerable inter-individual variation was present. The current study describes compositional changes in the faecal bacteriome associated with the transition from a fibre-based to a high-starch diet in ponies and emphasises the individual nature of dietary responses, which may reflect functional differences in the bacterial populations present in the hindgut.

Gastrointestinal microbial communities are increasingly being implicated in host susceptibilities to nutritional/metabolic diseases; such conditions are more prevalent in obese and/or older horses. This controlled study evaluated associations between host-phenotype and the fecal microbiome / metabolome. Thirty-five, Welsh Mountain pony mares were studied across 2 years (Controls, n = 6/year, 5–15 years, Body Condition Score (BCS) 4.5–6/9; Obese, n = 6/year, 5–15 years, BCS > 7/9; Aged, n = 6 Year 1; n = 5 Year 2, ≥19 years old). Animals were individually fed the same hay to maintenance (2% body mass as daily dry matter intake) for 2 (aged / obese) or 4 (control), 4-week periods in a randomized study. Outset phenotype was determined (body fat%, markers of insulin sensitivity). Feces were sampled on the final 3 days of hay feeding-periods and communities determined using Next Generation Sequencing of amplified V1–V2 hypervariable regions of bacterial 16S rRNA. Copy numbers for fecal bacteria, protozoa and fungi were similar across groups, whilst bacterial diversity was increased in the obese group. Dominant bacterial phyla in all groups were Bacteroidetes > Firmicutes > Fibrobacter. Significant differences in the bacterial communities of feces were detected between host-phenotype groups. Relative to controls, abundances of Proteobacteria were increased for aged animals and Bacteroidetes, Firmicutes, and Actinobacteria were increased for obese animals. Over 500 bacterial operational taxonomic units (OTUs) differed significantly between host-phenotype groups. No consistent pattern of changes in discriminant OTUs between groups were maintained across groups and between years. The core bacterial populations contained 21 OTUs, 6.7% of recovered sequences. Distance-based Redundancy Analyses separated fecal bacterial communities with respect to markers of obesity and insulin dysregulation, as opposed to age. Host-phenotype had no impact on the apparent digestibility of dietary GE or DM, fecal volatile fatty acid concentrations or the fecal metabolome (FT-IR). The current study demonstrates that host-phenotype has major effects on equine fecal microbial population structure. Changes were predominantly associated with the obese state, confirming an obesity-associated impact in the absence of nutritional differences. Clear biomarkers of animal-phenotype were not identified within either the fecal microbiome or metabolome, suggesting functional redundancy within the gut microbiome and/or metabolome.

Objectives To determine the mortality rates associated with equine anaesthesia for elective and emergency (colic and non-colic) cases in one equine, university teaching hospital and to investigate the effect of several horse- and anaesthetic-related variables on anaesthetic recovery quality. Study design Retrospective data analysis. Animals or animal population In total, 1416 horses undergoing anaesthesia between May 2010 and December 2013. Methods Patient information and details of the anaesthetic, recovery period and immediate complications were extracted from an archiving database. Statistical evaluation of factors affecting mortality included chi-squared tests and binary logistic regression. Factors affecting recovery quality were investigated using univariable and multivariable ordinal logistic regression. Statistical significance was set at p Results Anaesthesia/recovery-related mortality was 1.1% for all cases, 0.9% for elective cases, 1.6% for colics and 0% for non-colic emergencies. Fractures and dislocations accounted for the majority (71.4%) of deaths. No intra-operative deaths occurred during the study period. Risk factors for mortality included increasing age and American Society of Anesthesiologist's (ASA) status but these and other factors were confounded by ‘colic’. Non-fatal complications in the immediate recovery period included postanaesthetic myopathy/neuropathy and postanaesthetic respiratory obstruction. Recovery quality was associated with body mass ( p = 0.016), ASA status 3 and 4 ( p = 0.020 and 0.002, respectively), duration of anaesthesia ( p p = 0.013). Although recovery quality was also influenced by age and breed-type, these factors were removed from the final model as age was highly associated with both ASA status ( p p Conclusion and clinical relevance Anaesthetic/recovery-associated mortality was comparable to previously reported figures except intra-operative deaths were not reported. Fractures remained responsible for the largest proportion of recovery-associated deaths. Improvements to the recovery process that can reduce fracture occurrence are still required.

Synovitis of the navicular bursa is common in performance horses. The objective of this study was to describe an ultrasound-guided technique to inject a distended navicular bursa and to evaluate its feasibility for use by a clinician not trained in the technique. Twenty distal limbs of horses of various breeds and sizes were used. To produce synovial distension, the navicular bursa of each limb was injected with contrast medium using a lateral approach and radiography was performed to confirm that the contrast medium was distending the bursa. The digit was positioned with the distal interphalangeal joint in hyperextension. A microconvex ultrasound probe was placed in the hollow of the pastern, palmar to the middle phalanx and the region was assessed in a transverse plane slightly oblique to the horizontal plane. The ultrasound probe was rotated to visualize both the lateral and medial recesses and to select which side was more distended to inject. A 21G 0.8 × 50 mm needle was inserted abaxially to the probe in the plane of the ultrasound beam into the proximal recess of this navicular bursa and a methylene blue solution was injected. Following injection, dissection was performed to assess whether the navicular bursa had been successfully injected. This ultrasound-guided technique was reliably performed with a success rate of 68%. The success of injection is influenced by hyperextension of the foot, quality of ultrasound images and degree of distension of the bursa.

The objective of the study was to determine the minimal anaesthetic concentration (MAC) of sevoflurane (SEVO) in pigeons and investigate the effects of 1 MAC SEVO anaesthesia on cardiovascular and respiratory variables compared with the awake state. This is a prospective, experimental study. Animals were seven healthy adult pigeons. After acclimatisation to handling, heart rate (HR), heart rhythm, respiratory rate (fR), end-expired carbon dioxide tension (PE'CO2), inspired CO2 tension, indirect systolic arterial blood pressure (SAP) and cloacal temperature were measured to determine baseline, 'awake' values. Pigeons were then anaesthetised with SEVO and MAC was determined by the 'bracketing' method. The same variables were monitored during a 40 minute period at 1.0 MAC SEVO for each bird. Mean MAC was 3.0±0.6 per cent for SEVO. During maintenance of anaesthesia at 1.0 MAC, SAP decreased significantly (P

Objectives To review the literature concerning mortality associated with general anaesthesia in horses and to assess whether there is evidence for a reduction in mortality over the 20 years since the Confidential Enquiry into Perioperative Equine Fatalities (CEPEF). Databases used PubMed, Scopus, Google Scholar. Search terms used: horse; pony; equine; anaesthesia; anesthesia; recovery; morbidity, and mortality. Conclusions The most recent studies, in which isoflurane and sevoflurane have been more commonly used for anaesthesia maintenance, report fewer intraoperative cardiac arrests than older studies in which halothane was favoured. Catastrophic fractures, however, have become the greatest cause of recovery-associated mortality.

Reduction of the hyperinsulinaemic response to feeding is central to the management of insulin dysregulation (ID). The aim of this study was to compare insulinaemic and glycaemic responses to soaked hay, dry hay and haylage in ponies. Twelve ponies of mixed breeds were maintained under identical management conditions. A randomised four-way crossover trial was conducted, in which fasted animals were fed a meal of 0.25% body weight as dry matter intake soaked hay, dry hay or haylage, or administered an oral glucose test (OGT). Blood glucose and serum insulin concentrations were measured before and at 2h following OGT, and regularly for 5h following forage meals. Median and interquartile range (IQR) area under the curve (AUC) for insulin (AUCi) was greater for haylage (median 6495; IQR 17352) vs. dry hay (2932; IQR 5937; P=0.019) and soaked hay (1066; IQR 1753; P=0.002), and greater for dry hay vs. soaked hay (P=0.002). The AUC for glucose (AUCg) was lower for soaked hay (1021; IQR 99) vs. dry hay (1075; IQR 105; P=0.002) and haylage (1107; IQR 221; P=0.003). Six ponies were classified as having ID based on the OGT. AUCi was greater in ID vs. non-ID ponies after all forages. In contrast, there was no detectable effect of ID status on AUCg. On an equivalent dry matter basis, soaked hay produced the lowest insulinaemic and glycaemic responses to feeding, while haylage produced the highest responses. The insulinaemic effects of all forages were greater in ponies with ID. These data support the practice of soaking hay with water to reduce postprandial insulinaemic responses in ponies.

Body condition scoring systems were originally developed to quantify flesh cover in food animals and are commonly used to evaluate body fat in Equidae. The relationship between concurrent estimates of body fat content (eTBF%, deuterium oxide dilution; range, 2.7-35.6%) and subjective appraisals of body 'fatness' (body condition score, BCS; range, 1.25-9/9), was investigated in 77 mature horses and ponies. Univariate (UVM, r(2)=0.79) and multivariable (MVM, r(2)=0.86) linear regression models described the association, where BCS and eTBF% were explanatory and outcome variables, respectively. Other measures (age, sex, breed, body mass, ultrasound-generated subcutaneous and abdominal retroperitoneal fat depths, withers height, heart and belly circumferences) were considered as potential confounders but only height, belly circumference and retroperitoneal fat depth remained in the final MVM. The association between BCS and eTBF% was logarithmic. Appraisal of the transformed regression (UVM), actual eTBF% values and 95%CIs of the model forecast, suggested that the power of log-transformed BCS as a predictor of eTBF% decreased as BCS increased. The receiver operating characteristic curve for the prediction of horses with an eTBF% of >20%, suggested that the UVM correctly classified 76% of horses using a 'cut-off' of BCS 6.83/9 (sensitivity, 82.5%; specificity, 70.8%). Negative values for eTBF% were obtained for two thin ponies which were excluded from analyses, and caution is advised in the application of deuterium dilution methodologies where perturbed tissue hydration could be predicted. The data suggest that BCS descriptors may warrant further consideration/refinement to establish more clinically-useful, sub-classifications for overweight/obese animals.

Escherichia coli O115 has been isolated from healthy sheep and was shown to be associated with attaching-effacing (AE) lesions in the large intestine. Following previous observations of interactions between E. coli O157 and O26, the aim of the present study was to assess what influence an O115 AE E. coli (AEEC) would have on E. coli O157 colonisation in vitro and in vivo. We report that E. coli O115- and O157-associated AE lesions were observed on HEp-2 cells and on the mucosa of ligated ovine spiral colon. In single strain inoculum, E. coli O115 associated intimately with HEp-2 cells and the spiral colon in greater numbers than E. coli O157:H7. However, in mixed inoculum studies, the number of E. coli O115 AE lesions was significantly reduced suggesting negative interference by E. coli O157. Use of the ligated colon model in the present work has allowed in vitro observations to be extended and confirmed whilst using a minimum of experimental animals. The findings support a hypothesis that some AEEC can inhibit adhesion of other AEEC in vivo. The mechanisms involved may prove to be of utility in the control of AE pathovars.

Dietary restriction for the weight-loss management of obese horses limits the natural trickle-feeding behaviour. During feed restriction, wood shavings are often advised as bedding to prevent dietary supplementation from non-feed sources. Data from twelve overweight/obese horses and ponies of mixed breed and sex, bedded on wood shavings during 16 weeks of feed restriction, were retrospectively evaluated. DM intake (DMI) was restricted to 1·25 % of body mass (BM) daily. Animals were randomly assigned to one of two diets (hay/chaff, n 6; hay/balancer meal, n 6). BM was recorded weekly. Feeding behaviour was recorded by continual observation over 24 h during week 15. The apparent digestibility (gross energy (GE), acid-detergent fibre (ADF) and DM) of feed was determined for all animals by total faecal collection (72 h, week 16). Rates of weight loss were independent of diet type, DM (R2 0·15), GE (R2 0·20) and ADF digestibilities (R2 0·18). Despite similar DMI, faecal DM ranged between 0·52 and 1·16 % of BM daily and was associated with wide ranges in apparent digestibility (GE − 11·34 to 53·08 %; ADF − 50·37 to 42·83 % and DM 2·14 to 57·32 %), which were improbably low for some animals. Apparent digestibilities were associated with DM output (GE R2 0·96; ADF R2 0·99 and DM R2 0·99) and time spent feeding (GE R2 0·62; DM R2 0·61 and ADF R2 0·59), indicating that feed intake was supplemented with wood shavings in at least five of the twelve animals. Quantities of wood shavings ingested (negligible to >3·0 kg/d) were back-calculated from predicted feed digestibilities. All animals remained healthy. Implications of ‘feed-bulking/energy dilution’ for feed-restricted animals need further consideration.

REASONS FOR PERFORMING THE STUDY: Excessive accumulations or depletions of body fat have been associated with increased morbidity and mortality in horses and ponies. An objective, minimally-invasive method to accurately quantify body fat in living animals is required to aid nutritional management and define welfare/performance limits. OBJECTIVES: To compare deuterium oxide (D(2) O) dilution-derived estimates of total body water (TBW) and body fat with values obtained by 'gold standard' proximate analysis and cadaver dissection. HYPOTHESIS: D(2) O dilution offers a valid method for the determination of TBW and body fat in equids. METHODS: Seven mature (mean ± s.e. 13 ± 3 years, 212 ± 14 kg, body condition scores 1.25-7/9), healthy, Welsh Mountain pony mares, destined for euthanasia (for nonresearch purposes) were used. Blood samples were collected before and 4 h after D(2) O (0.11-0.13 g/kg bwt, 99.8 atom percent excess) administration. Plasma was analysed by gas isotope ratio mass spectrometry following filtration and zinc reduction. After euthanasia, white adipose tissue (WAT) mass was recorded before all body tissues were analysed by proximate chemical analyses. RESULTS: D(2) O-derived estimates of TBW and body fat were strongly associated with proximate analysis- and dissection-derived values (all r(2) >0.97, P≤0.0001). Bland-Altman analyses demonstrated good agreements between methods. D(2) O dilution slightly overestimated TBW (0.79%, limits of agreement (LoA) -3.75-2.17%) and underestimated total body lipid (1.78%, LoA -0.59-4.15%) and dissected WAT (0.72%, LoA -2.77-4.21%). CONCLUSIONS AND POTENTIAL RELEVANCE: This study provides the first validation of the D(2) O dilution method for the minimally-invasive, accurate, repeatable and objective measurement of body water and fat in living equids.

Objective—To assess sedative and cardiopulmonary effects of premedication with a medetomidine-buprenorphine or acepromazine-buprenorphine combination in dogs anesthetized with propofol and isoflurane. Design—Randomized controlled clinical trial. Animals—90 dogs undergoing routine surgical and diagnostic procedures. Procedures—Dogs were randomly assigned to 1 of 3 premedication groups: group 1 (acepromazine, 0.03 mg/kg [0.014 mg/lb], IM; buprenorphine, 0.02 mg/kg [0.009 mg/lb], IM), 2 (medetomidine, 5 μg/kg [2.3 μg/lb], IM; buprenorphine, 0.02 mg/kg, IM), or 3 (medetomidine, 10 μg/kg [4.5 μg/lb], IM; buprenorphine, 0.02 mg/kg, IM). Anesthesia was induced with propofol and maintained with isoflurane in oxygen. Simple descriptive scores for sedation were assigned 15 minutes (groups 2 and 3) and 30 minutes (group 1) after premedication administration. Basic cardiopulmonary data were recorded throughout the anesthetic period. Times to recovery from anesthesia were recorded. Results—Sedation scores did not differ significantly among groups. Mean and diastolic blood pressures were significantly lower and heart rate was significantly higher in group 1 than in the other groups. Mean end-tidal partial pressure of CO2 was significantly lower and respiratory rate was significantly higher in group 1 than in the other groups. There were no significant differences in anesthetic recovery times between groups. Conclusions and Clinical Relevance—Results suggested that either acepromazine or medetomidine could be used in combination with buprenorphine for premedication of dogs anesthetized with propofol and isoflurane for routine surgical and diagnostic procedures. Arterial blood pressure was better maintained with the medetomidine-buprenorphine combinations, but tissue perfusion was not investigated.

Summary Reasons for performing study: Increased prevalence of obesity among UK horses and ponies demands evidence-based advice to promote weight loss. Hypothesis: Restriction of dry matter intake (DMI) to 1% of body mass (BM, 6% of predicted maintenance digestible energy [DE] requirements) would promote weight loss without compromise to health. Methods: Five mature (mean ± s.e. 10 ± 2 years), overweight/obese pony mares (BM, 257 ± 20 kg: body condition score [BCS] 6.8/9 ± 0.5) were studied over 12 weeks. Animals were individually housed. Daily provision of a chaff-based, complete diet (measured DE, 8.5 MJ/kg DM) was restricted to 1% of actual BM as DMI daily. BCS, girth measurements and ultrasound-derived measures of subcutaneous fat depth overlying the gluteal region and 12th intercostal space (rib-eye) were recorded weekly. Body fat content was estimated at the beginning and end of the study by deuterium oxide dilution methods. Clinical biochemistry was monitored weekly. Behaviour was observed (24 h, 3/5 ponies) on 3 occasions. Results: BM decreased by 4.3 ± 1.1% during the first week and thereafter by 0.7 ± 0.1% of BM at end of Week 1 each week. BCS remained constant. Heart and belly girths, rump width and subcutaneous fat depth at rib-eye decreased significantly with time and BM. Fat comprised 45 ± 19% of BM loss. Fatter animals lost relatively more fat. With decreased feeding activity, time spent in ‘play’ and rest increased by 36 ± 11% and 438 ± 95%, respectively. Conclusions: This plane of nutrition resulted in an overall rate of weight loss of 1% of outset BM weekly. BCS was not a useful index of early weight loss but heart and belly girths and subcutaneous rib-eye fat were identified as alternative markers. Potential relevance: This study provides an evidence-base for the management of weight loss in obese animals, especially those for which exercise may be contra-indicated.

OBJECTIVES To investigate pethidine's effects on sedation and cardiovascular variables in dogs premedicated with dexmedetomidine. METHODS Sixty American Society of Anesthesiologists (ASA) I dogs were presented for routine neutering. Heart rate was measured at admission. Dogs were randomly assigned to one of the five groups to decide premedication; group D5+P (dexmedetomidine 5 microg/kg plus pethidine 5 mg/kg), D10+P (dexmedetomidine 10 microg/kg plus pethidine 5 mg/kg) with three control groups, D5 (dexmedetomidine 5 microg/kg), D10 (dexmedetomidine 10 microg/kg) or P (pethidine 5 mg/kg). Heart rate was measured at 3, 5, 10 and 20 minutes after preanaesthetic medication. Simple descriptive scores for sedation were assigned after 20 minutes. Anaesthesia was induced using propofol and maintained using isoflurane in oxygen. Heart rate was recorded throughout anaesthesia. RESULTS Sedation scores after preanaesthetic medication were significantly higher (P

Laryngeal paralysis in horses has been reported after inhalational anesthesia and can result in significant morbidity/mortality. The cause of the condition is unclear. The objective of this study was to examine the effects of a standardized anesthetic protocol on laryngeal function and laryngeal/pharyngeal trauma in the peri-anesthetic period in a prospective study. A 30- to 60-second digitalized video clip of laryngeal movement from a standardized endoscopic view was recorded at five time points: before sedation, post-sedation, post-induction, immediately after recovery to standing, and at 24 hours after recovery. A standardized anesthetic regimen was used in all cases. Video clips were randomized and evaluated by two blinded assessors. Each assessor scored each clip for laryngeal function and trauma using previously validated scoring systems. Agreement between assessors was calculated using the mean of the five time-specific weighted kappa statistics. Post-anesthesia laryngeal function and trauma scores were compared with initial scores using the Wilcoxon signed rank test with Bonferroni adjustment. Spearman's rank coefficient was used to assess correlation between trauma and function scores and between anesthetic duration and laryngeal function and trauma scores. There was no significant effect of anesthesia on laryngeal function. Trauma scores were not significantly higher after tracheal intubation. The trauma scoring system requires further validation. There was no correlation between higher trauma scores and laryngeal function or duration and laryngeal function or trauma. Further work is required to evaluate other variables that may affect laryngeal function after anesthesia, using a larger number of horses with varying degrees of laryngeal dysfunction.

Monitoring the composition of gases breathed by anaesthetised patients requires measurement methods with fast responses, high accuracy and good reliability. There is also an increasing demand for systems to be able to monitor more than one target analyte simultaneously, but some gas analysers can be sensitive to the presence of methane gas in exhaled breath, consequently leading to inaccurate measurements of the anaesthetic agent. This study investigated the feasibility of employing portable quadrupole mass spectrometry to monitor volatile anaesthetic agents (halothane, isoflurane and sevoflurane), methane accumulation in anaesthetic rebreathing systems, and inspired and exhaled carbon dioxide and oxygen concentrations during equine anaesthesia in a clinical setting. The volatile anaesthetic agents were easily measurable and methane was detectable. The instrument had an advantage over short wavelength infrared absorption spectrometry analysers because it could monitor anaesthetic agents and other respiratory gases simultaneously and at extremely low concentrations, although further optimisation is required.

In this study, we used mouse ileal loops to investigate the interaction of enterohemorrhagic Escherichia coli (EHEC) O157:H7 with the mouse intestinal mucosa. With a dose of 10(9) and 3 h incubation, EHEC O157 was detected in the lumen and to a lesser extent associated with the epithelium. Typical attaching and effacing (A/E) lesions were seen, albeit infrequently. While the effector protein Tir was essential for A/E lesion formation, the bacterial type III secretion system adaptor protein TccP was dispensable. These results suggest that A/E lesions on mouse intestinal mucosa can be formed independently of robust actin polymerization.

Objective A clinical trial to determine whether continuous infusion administration technique was suitable for maintaining neuromuscular blockade with rocuronium bromide in dogs. Animals Twenty-two dogs, 10 males and 12 females, median age 2 years 4 months, median weight 32 kg undergoing elective surgical procedures under general anaesthesia: ASA classification I or II. Materials and methods After induction of anaesthesia, neuromuscular function was evaluated using train-of-four (TOF) stimulation of the dorsal buccal branch of the facial nerve. A bolus dose of 0.5 mg kg−1 rocuronium was administered intravenously and an infusion of 0.2 mg kg−1 hour−1 was started immediately. Neuromuscular blockade was assessed visually by counting the number of twitches observed during TOF stimulation repeated at 10-second intervals. Results The bolus dose of rocuronium abolished the response to TOF stimulation in 21 of the 22 dogs. The median onset time of neuromuscular blockade (complete loss of all four twitches) was 82 seconds (range 38–184 seconds). Median infusion duration was 76 minutes (range 20.3–146 minutes). Conclusions and clinical relevance This protocol of rocuronium administration was considered to be effective in dogs. Constant infusion of rocuronium is easily applicable to clinical practice and further work is required on infusion titration.

A 13-year old Thoroughbred cross gelding (528 kg) underwent lameness investigation. Because of his temperament, general anesthesia was required to facilitate ultrasound of the left fore fetlock and intra-articular medication of three joints. Anesthesia was induced with ketamine/diazepam after acepromazine/detomidine premedication. Anesthesia was maintained for 40 minutes with a guaifenesin/detomidine/ketamine intravenous infusion. Recovery from anesthesia was initially uneventful, although of a moderate duration (70 minutes). Once standing, the horse proceeded to box walk in an agitated state and became recumbent on two occasions. The horse was manually restrained, at which time its rectal temperature was 41.8°C. Cooling measures were employed (fans, ice-water enemas, wet rugs, intravenous fluid therapy (IVFT), and topical application of surgical spirit) until rectal temperature reached 38.7°C. IVFT was continued for a further 16 hours. Four days after recovery from anesthesia, bilateral triceps, deltoideus, trapezius, and rhomboideus muscle swelling was observed. Blood creatinine kinase was elevated (24,898 IU/L). Treatment for postanesthetic myopathy was initiated (hot packing of the muscle groups, topical dimethylsulfoxide [DMSO] cream application, and oral phenylbutazone). Myoglobinuria was not observed at any time. Muscle swelling decreased over the following 3 days. The horse was discharged on day 11 and has since returned to work.

OBJECTIVE: To determine the effects of dobutamine and phenylephrine on intra- and postoperative survival in horses undergoing emergency abdominal surgery. STUDY DESIGN: Retrospective case analysis. ANIMALS: A total of 637 client-owned horses undergoing colic surgery. METHODS: Clinical details of horses admitted for colic surgery were recorded on a computer database. Information collected included history, clinical variables observed before surgery, anaesthesia and surgical details, and postoperative survival and morbidity rates. Details of specific importance for this study were those recorded during anaesthesia, in particular the duration of dobutamine and phenylephrine administration, separately and combined, and total anaesthesia time. Two outcomes were considered: 1) intra-operative death, i.e. death between time of pre-anaesthetic medication and recovery from anaesthesia (defined as horse walking from recovery box); and 2) all deaths, i.e. death at any time after induction of anaesthesia. The definition of 'death' included euthanasia. Univariable and multivariable statistical analyses were performed to evaluate the associations between dobutamine and/or phenylephrine use and these two outcomes. RESULTS: Results from univariable analyses suggested that dobutamine administration was not significantly associated with increased intra- or postoperative mortality. Phenylephrine administration showed univariable association with intra- and postoperative death. However, in multivariable models adjusted for the effects of heart rate and packed cell volume at admission, the phenylephrine effect was not significantly associated with intra-operative, or other types of death. CONCLUSION: This study provides no evidence to suggest that dobutamine or phenylephrine administration is associated with altered survival rates during or after colic surgery. CLINICAL RELEVANCE: Our study supports previous work, suggesting that pre-existing cardiovascular status is an important prognostic determinant in equine colic cases. It provides no evidence that dobutamine or phenylephrine administration is associated with survival.

Objective—To compare the effects of preoperatively administered pentastarch (10% concentration in isotonic saline [0.9% NaCl] solution) and hypertonic saline (7.2% NaCl) solutions on PCV and circulating total protein (TP) concentration in horses with colic undergoing emergency exploratory laparotomy and to assess survival rates of horses that received each treatment. Design—Prospective, randomized study. Animals—100 horses with signs of abdominal pain and PCV ≥ 0.46 L/L. Procedures—Horses received a 4 mL/kg (1.8 mL/lb) dose of pentastarch solution (n = 50) or hypertonic saline solution (50) over a 10- to 20-minute period before anesthetic induction. Blood samples were collected at the time of evaluation and ≤ 5 minutes after fluid resuscitation; changes in PCV and TP concentration were compared. Survival was evaluated by Kaplan-Meier and Cox proportional hazards analyses. Results—Age, weight, sex, PCV, and heart rate on initial examination were similar between treatment groups. Hypertonic saline solution treatment resulted in a significantly greater reduction in PCV (median change, −0.14 L/L) than did pentastarch treatment (median change, −0.07 L/L). Reduction in TP concentration was also significantly greater after hypertonic saline solution treatment (median change, −16 g/L) than after pentastarch treatment (median change, −2 g/L). Long-term survival was not significantly different between groups. Conclusions and Clinical Relevance—Despite a greater reduction in preanesthetic hemoconcentration following administration of hypertonic saline solution (4 mL/kg infusion, once), no difference in overall long-term survival was found between horses that received this treatment and those that received an equal volume of pentastarch solution. Findings suggested that, in a clinical setting, either of these fluids would be appropriate for preoperative fluid resuscitation in horses with colic.

Twenty entire female cats were randomly assigned to two groups of 10; the cats in one group underwent ovariohysterectomy by a midline approach and the cats in the other group by a flank approach. Cats were assessed for signs of pain and scores were assigned pre- and postoperatively. There was a tendency for the cats neutered by a flank approach to be in more pain postoperatively (P=0.05). The final pain score for cats in either group was equal to or lower than their baseline score.

Mortality rates for horses that have undergone emergency abdominal surgery are higher than for other procedures. Here, multivariable modelling of data from 774 surgical colic cases is used to identify pre-operative and anaesthesia-related variables associated with intra- and post-operative mortality. Intra-operative mortality was significantly (P

Objective To compare the induction dose requirements of thiopental using two different infusion rates for induction of anaesthesia in dogs. Study design Prospective, randomized study. Animals Fifty, healthy (ASA I or II) client-owned dogs with a mean age of 4.1 years and a mean mass of 20.4 kg undergoing elective surgery. Materials and methods Animals were randomly assigned to receive an infusion of 2.5% thiopental at a rate of either 0.1 ml kg −1 minute −1 or 0.4 ml kg −1 minute −1 , 30–40 minutes after pre-anaesthetic medication with intramuscular acepromazine (0.025 mg kg −1 ) and pethidine (3.5 mg kg −1 ). Thiopental administration was controlled by a precision syringe driver. Statistical analyses of the results, using the outcome ‘mg kg −1 required for induction’ (log-transformed) included unpaired t -tests for all categorical data (thiopental infusion rate, breed, sex, obesity, sedation quality) and univariable linear regression for continuous variables (mass, age). All variables were then considered in a multivariable linear regression model. The quality of induction with the two different infusion rates was also assessed. Results After controlling for quality of sedation, the thiopental induction dose requirement was significantly less ( p −1 ; range 4.9–13.7) compared with the faster infusion rate (median =11.0 mg kg −1 ; range 6.6–18.0). The quality of sedation also affected the dose required ( p = 0.03). The slower infusion rate was associated with a significantly poorer induction quality ( p = 0.3). Conclusions Slow thiopental infusion (0.1 ml kg −1 minute −1 ) for anaesthesia induction after acepromazine/pethidine pre-anaesthetic medication reduced the induction dose requirement, although the quality of induction was inferior. Clinical relevance The induction dose of thiopental was reduced with a slower administration rate and so slow administration is recommended in thiopental-sensitive animals.

The addition of hay soaking to current nutritional advice for weight loss management for equine obesity lacks clinical evidence. Twelve overweight/obese horses and ponies were used to test the hypothesis that feeding soaked hay at 1.25% of body mass (BM) daily as dry matter (DM) before soaking would elicit weight losses within the target 0.5-1.0% of BM weekly. Six animals were used to evaluate the impact of nutrient-leaching on the digestibility and daily intakes of dietary energy and nutrients. Soaked hay DM was corrected in accordance with the 'insoluble' ADF content of fresh and soaked hays. The ADF-based method was validated using a test-soaking protocol. Animals fed soaked hay for 6 weeks lost 0.98 ± 0.10% of BM weekly. The most weight loss sensitive animal lost ~2% of BM weekly. Soaking hay did not alter DM gross energy concentrations, incurred losses of water soluble carbohydrates (WSC) and ash and increased acid detergent fibre (ADF) concentrations. Digestibilities of GE, DM, ash and WSC were unaltered but soaking increased uncorrected values for crude protein (+12%) and ADF (+13.5%) digestibility. Corrected DM provision was only 1% of BM daily, providing 64% of maintenance DE requirements, a 23.5% increase in the intended magnitude of energy restriction. Hay soaking leached nutrients, reduced DM and DE provision and was associated with accelerated weight losses over those expected had fresh-hay been fed to the same level. The ADF-based method will allow the predictive evaluation of individual hays to direct feeding management and prevent inadvertently severe DM and energy restriction.

There are indications that motivation correlates with better performance for those studying veterinary medicine. To assess objectively whether motivation profiles influence both veterinary students' attitudes towards educational interventions and their academic success and whether changes in curriculum can affect students' motivation, there is need for an instrument that can provide a valid measurement of the strength of motivation for the study of veterinary medicine. Our objectives were to design and validate a questionnaire that can be used as a psychometric scale to capture the motivation profiles of veterinary students. Question items were obtained from semi-structured interviews with students and from a review of the relevant literature. Each item was scored on a 5-point scale. The preliminary instrument was trialed on a cohort of 450 students. Responses were subjected to reliability and principal component analysis. A 14-item scale was designed, within which two factors explained 53.4% of the variance among the items. The scale had good face, content, and construct validities as well as a good internal consistency (Cronbach's alpha=.88).

EQUINE metabolic syndrome (EMS), defined as obesity, insulin resistance and an increased risk of laminitis, is becoming increasingly recognised as an important condition with serious welfare implications (Frank and others 2010). Dietary restriction is critical for the management of EMS, and using a low starch and sugar content diet has been shown to improve insulin sensitivity in overweight and obese horses and ponies (Dugdale and others 2010, Argo and others 2012). Feeding hay with a non-structural carbohydrate (NSC) content of

THIS article discusses the anatomy and physiology of the thorax and considers the conditions requiring chest drainage. The techniques of needle thoracentesis and tube thoracostomy are described, followed by a discussion of patient aftercare and potential problems.

Tracheal rupture and stenosis are well-reported problems in human beings and cats following endotracheal intubation. However, this problem has been rarely reported in dogs. This case report describes a case of tracheal necrosis 5 days following endotracheal intubation in a dog associated with overinflation of the endotracheal tube cuff and multiple changes in position.

In veterinary medical education, it is now necessary to design competency frameworks (CFs) that list expected competencies at graduation. Three different CFs with different formats and contents have been published in Europe, such as the Day One Skills (DOS), the recommendations of the World Organization for Animal Health (OIE), and the Veterinary Professional (VetPro). In the current study, on the basis of a survey among Belgian veterinarians, a fourth document was designed that lists the necessary knowledge, skills, and attitudes grouped into families according to professional situations. The objectives of this study were to assess the perception of CFs by various categories of stakeholders, identify the possible uses of CFs, and determine whether one format should be preferred to another. We used a qualitative approach based on semi-structured face-to-face interviews with different stakeholders after they had reviewed the four different documents (CFs). This study showed that an obligation to design CFs was clearly perceived by academic and professional authorities. Teachers and veterinarians may be either enthusiastic or apprehensive about CFs, while students perceive the usefulness of the documents to plan and assess their learning objectives. Three main roles of CFs were identified: they can be used as communication tools, regulatory tools, or educational tools. However, not one of the documents used in this study was perceived to fulfill all roles. It is therefore likely that no one ideal document yet exists and a combination of formats is necessary.

Objective The aim of this study was to investigate normal values for the dynamic compliance of the respiratory system (Crs) and respiratory system resistance (Rrs) in mechanically ventilated anaesthetized dogs. Study design Prospective clinical study. Animals Forty healthy dogs undergoing elective orthopaedic surgery. Body weight was (mean ± SD) 26.8 ± 10.7 kg (range: 1.9–45.0 kg), age 4.7 ± 2.9 years (range: 0.1–10.6 years). Methods Dogs were premedicated with acepromazine and methadone administered intramuscularly and anaesthesia induced with propofol intravenously. After endotracheal intubation the dog's lungs were connected to an appropriate breathing system depending on body weight and isoflurane in oxygen administered for maintenance of anaesthesia. The lungs were ventilated mechanically with variables set to maintain normocapnia (end‐tidal carbon dioxide concentration 4.7–6.0 kPa). Peak inspiratory pressure, Crs, Rrs, tidal volume, respiratory rate and positive end‐expiratory pressure were recorded at 5, 30, 60, 90 and 120 minutes after start of mechanical ventilation. Cardiovascular variables were recorded at time of collection of respiratory data. Results General additive modeling revealed the following relationships: Crs = [0.895 × body weight (kg)] + 8.845 and Rrs = [−0.0966 × body weight (kg)] + 6.965. Body weight and endotracheal tube diameter were associated with Crs ( p 0.001 and p = 0.002 respectively) and Rrs ( p = 0.017 and p = 0.002 respectively), body weight being linearly related to Crs and inversely to Rrs. Conclusion and clinical relevance Body weight was linearly related to Crs while Rrs has an inverse linear relationship with body weight in mechanically ventilated dogs. The derived values of Crs and Rrs may be used for monitoring of lung function and ventilation in healthy dogs under anaesthesia.

Objective To determine if body condition score (BCS) influences the sedative effect of intramuscular (IM) premedication or the dose of intravenous (IV) propofol required to achieve endotracheal intubation in dogs. Study design Prospective clinical study. Animals Forty–six client–owned dogs undergoing general anaesthesia. Methods Dogs were allocated to groups according to their BCS (BCS, 1 [emaciated] to 9 [obese]): Normal–weight Group (NG, n = 25) if BCS 4–5 or Over–weight Group (OG, n = 21) if BCS over 6. Dogs were scored for sedation prior to IM injection of medetomidine (5 μg kg−1) and butorphanol (0.2 mg kg−1) and twenty minutes later anaesthesia was induced by a slow infusion of propofol at 1.5 mg kg−1 minute−1 until endotracheal intubation could be achieved. The total dose of propofol administered was recorded. Data were tested for normality then analyzed using Student t–tests, Mann–Whitney U tests, chi–square tests or linear regression as appropriate. Results Mean ( ± SD) propofol requirement in NG was 2.24 ± 0.53 mg kg−1 and in OG was 1.83 ± 0.36 mg kg−1. The difference between the groups was statistically significant (p = 0.005). The degree of sedation was not different between the groups (p = 0.7). Post–induction apnoea occurred in 11 of 25 animals in the NG and three of 21 in OG (p = 0.052). Conclusions Overweight dogs required a lower IV propofol dose per kg of total body mass to allow tracheal intubation than did normal body condition score animals suggesting that IV anaesthetic doses should be calculated according to lean body mass. The lower dose per kg of total body mass may have resulted in less post–induction apnoea in overweight/obese dogs. The effect of IM premedication was not significantly affected by the BCS. Clinical relevance Induction of general anaesthesia with propofol in overweight dogs may be expected at lower doses than normal–weight animals.

Evidence-based, weight loss management advice is required to address equine obesity. Changes in body mass (BM), body condition score (BCS), heart (HG) and belly circumference (BG), direct (ultrasonographic) and indirect (D(2)O dilution, bioelectrical impedance analysis [BIA]) measures of body fat as well as indices of insulin resistance (IR) were monitored in 12 overweight (BCS ≥ 7/9) horses and ponies of mixed breed and gender for 16 weeks. Animals were randomly assigned to two groups (Group 1, n=6, BCS 7.6/9 ± 0.6, 489 ± 184.6 kg; Group 2, n=6, BCS 8.1/9 ± 0.6, 479 ± 191.5 kg). Daily dry matter intake (DMI) was restricted to 1.25% BM as one of two, near-isocaloric (DE ∼0.115 MJ/kg BM/day), forage-based diets (Group 1, 0.8% BM chaff-based feed: 0.45% BM hay; Group 2, 1.15% BM hay: 0.1% BM nutrient-balancer). Statistical modelling revealed considerable between-animal heterogeneity in proportional weight losses (0.16-0.55% of Week 1 BM weekly). The magnitude of weight loss resistance (WLR) or sensitivity to dietary restriction was independent of diet or any measured outset variable and was largely (65%) attributed to animal identity. Predicted rates of weight loss decreased over time. BCS and BIA were poor estimates of D(2)O-derived body fat%. Reciprocal changes in depths of retroperitoneal and subcutaneous adipose tissues were evident. Changes in BG were associated with losses in retroperitoneal fat and BM (r(2), 0.67 and 0.79). Indices of IR improved for 9/12 animals by Week 16. For obese animals, weight loss should be initiated by restricting forage DMI to 1.25% BM. Subsequent restriction to 1% BM may be warranted for WLR animals.

The prebiotic Bimuno® is a mixture containing galactooligosaccharides (GOSs), produced by the galactosyltransferase activity of Bifidobacterium bifidum NCIMB 41171 using lactose as the substrate. Previous in vivo and in vitro studies demonstrating the efficacy of Bimuno® in reducing Salmonella enterica serovar Typhimurium (S. Typhimurium) colonization did not ascertain whether or not the protective effects could be attributed to the prebiotic component GOS. Here we wished to test the hypothesis that GOS, derived from Bimuno®, may confer the direct anti-invasive and protective effects of Bimuno®. In this study the efficacy of Bimuno®, a basal solution of Bimuno® without GOS [which contained glucose, galactose, lactose, maltodextrin and gum arabic in the same relative proportions (w/w) as they are found in Bimuno®] and purified GOS to reduce S. Typhimurium adhesion and invasion was assessed using a series of in vitro and in vivo models. The novel use of three dimensionally cultured HT-29-16E cells to study prebiotics in vitro demonstrated that the presence of ∼5 mg Bimuno® ml−1 or ∼2.5 mg GOS ml−1 significantly reduced the invasion of S. Typhimurium (SL1344nalr) (P−1 significantly reduced the adherence of S. Typhimurium (SL1344nalr) (P® or GOS prevented the adherence or invasion of S. Typhimurium to enterocytes, and thus reduced its associated pathology. This protection appeared to correlate with significant reductions in the neutral and acidic mucins detected in goblet cells, possibly as a consequence of stimulating the cells to secrete the mucin into the lumen. In all assays, Bimuno® without GOS conferred no such protection, indicating that the basal solution confers no protective effects against S. Typhimurium. Collectively, the studies presented here clearly indicate that the protective effects conferred by Bimuno® can be attributed to GOS.

Changes in appetite, body mass (BM), body condition score (BCS), direct (ultrasonographic) and indirect (deuterium oxide dilution technique) measures of body fat were monitored in Welsh Mountain pony mares (n=11, 5-19 years of age) offered ad libitum access to a complete diet (gross energy 16.9±0.07 MJ/kg dry matter) for 12 weeks during summer (n=6; 246±20 kg) and winter (n=5; 219±21 kg). At the outset, each group comprised two thin (BCS 1-3/9), moderate (BCS 4-6/9) and obese (BCS 7-9/9) animals. For ponies that were non-obese at the outset, BM was gained more rapidly (P=0.001) in summer (0.8±0.1 kg/day) than winter (0.6±0.0 kg/day). This was associated with a seasonal increase in dry matter intake (DMI) which became maximal (summer, 4.6±0.3% BM as DMI/day; winter, 3.5±0.1% BM as DMI/day) during the second month. The appetite of the obese ponies was half that reported for non-obese animals in the summer and BM remained constant irrespective of season. Body 'fatness' increased progressively for non-obese but not obese ponies. Body fat content was exponentially associated with increasing BCS but BCSs >6 were not useful indicators of actual body fat. Endogenous circannual mechanisms to suppress winter weight gain were insufficient to prevent the development of obesity in ad libitum fed ponies.

Monitoring blood pressure during anaesthesia is widely recommended in man and animals. The accuracy of any device used to measure blood pressure is an important consideration when selecting monitoring equipment, the ANSI/AAMI SP10 standard is widely cited in this respect in recent veterinary publications. Blood pressure was monitored using invasive and non-invasive techniques during clinical anaesthesia in 19 dogs. The results were compared using Bland-Altman analysis. The bias (and limits of agreement) between invasive and non-invasive measurement was 7.1 mmHg (+/−34.7) for systolic blood pressure, −1.8 mmHg (+/−27.4) for mean blood pressure and 6.9 mmHg (+/−27.5) for diastolic blood pressure. In a clinical setting the bias between invasive and non-invasive measurement techniques was similar or smaller than laboratory reports, however the limits of agreement were considerably wider suggesting that care should be exercised when interpreting NIBP values.

Objectives The objective of this study was to investigate medetomidine-buprenorphine preanaesthetic medication in cats. Methods Forty American Society of Anesthesiologists (ASA) I female cats were enrolled in this prospective, blinded, clinical study. Cats were randomised into one of four groups: group M30 were injected intramuscularly with 30 microg/kg medetomidine, groups M10+B, M30+B and M50+B received 10, 30 and 50 microg/kg of medetomidine, respectively, each in combination with 20 microg/kg buprenorphine. After 30 minutes, a sedation score was allocated. Anaesthesia was induced using intravenous propofol and maintained using isoflurane in oxygen, while cats underwent ovariohysterectomy. Heart rate, respiratory rate, end-tidal carbon dioxide tension and oxygen saturation of haemoglobin were recorded. Atipamezole was administered intramuscularly at volatile agent discontinuation. Time taken to lift their head, sit in sternal and stand were recorded along with quality of recovery. Results M30+B cats required significantly less isoflurane compared with M30 cats. Heart rate and oxygen saturation of haemoglobin were significantly lower in M50+B cats than in M30 cats. All M+B groups experienced significantly better recoveries compared with the medetomidine only M30 control group. Clinical significance The addition of buprenorphine to medetomidine preanaesthetic medication in cats reduces volatile agent vaporiser setting and improves the quality of recovery from anaesthesia.

Objective To compare the brightness of South American camelid venous blood to that of Equidae. Study design Prospective clinical evaluation. Animals Twelve South American camelids (eight llamas, four alpacas), eight horses and ponies (control group). Methods Appropriately sized catheters were placed in the jugular vein of each animal under local anaesthesia. The blood spilt before the catheter was capped was caught on a white tile. A sample of blood was drawn for blood-gas analysis. The brightness of the blood (both on the tile and in the syringe) was matched to a colour chart (1 = darkest red, 8 = brightest red) by a single observer under bright light conditions. Packed cell volume (PCV) and partial pressure of oxygen (PvO2) in the blood were also measured on the syringe blood. Normally distributed data were compared using a two tailed t-test, and non-normally distributed data were compared using a Mann-Whitney U-test. Significance was set at p Results Camelid venous blood was significantly brighter red than that of horses and ponies both on the white tile (p = 0.0003) and in the syringe (p = 0.0001). PCV was significantly lower in camelids (32 ± 4%) compared with horses (37 ± 5%). Partial pressure of oxygen values were similar between groups. Conclusions and clinical relevance Jugular venous blood in alpacas and llamas is significantly brighter red than that of horses. Colour should not be used as a sole determinant of venous or arterial catheterization in this species.

The prebiotic Bimuno® is a mixture containing galactooligosaccharide, produced by the galactosyltransferase activity of Bifidobacterium bifidum NCIMB 41171 in the presence of lactose. Previous studies have implicated prebiotics in reducing infections by enteric pathogens, thus it was hypothesized that Bimuno® may confer some protection in the murine host from Salmonella enterica serovar Typhimurium (S. Typhimurium) infection. In this study, infection caused by S. Typhimurium SL1344nalr in the presence or absence of Bimuno® was assessed using tissue culture assays, a murine ligated ileal gut loop model and a murine oral challenge model. In tissue culture adherence and invasion assays with HT-29-16E cells, the presence of ∼2 mM Bimuno® significantly reduced the invasion of S. Typhimurium SL1344nalr (P® prevented colonization and the associated pathology of S. Typhimurium. In the BALB/c mouse model, the oral delivery of Bimuno® prior to challenge with S. Typhimurium resulted in significant reductions in colonization in the five organs sampled, with highly significant reductions being observed in the spleen at 72 and 96 h post-challenge (P=0.0002, ® significantly reduced the colonization and pathology associated with S. Typhimurium infection in a murine model system, possibly by reducing the invasion of the pathogen into host cells.

In this study, we used mouse ileal loops to investigate the interaction of enterohemorrhagic Escherichia coli (EHEC) O157:H7 with the mouse intestinal mucosa. With a dose of 10(9) and 3 h incubation, EHEC O157 was detected in the lumen and to a lesser extent associated with the epithelium. Typical attaching and effacing (A/E) lesions were seen, albeit infrequently. While the effector protein Tir was essential for A/E lesion formation, the bacterial type III secretion system adaptor protein TccP was dispensable. These results suggest that A/E lesions on mouse intestinal mucosa can be formed independently of robust actin polymerization.

LUXATION of the shoulder is an uncommon condition in large animals (Semevolos and others 1998), and has not pre-viously been reported in alpacas. Alpacas are raised primarily as companion animals, and have similar orthopaedic prob-lems to cattle. The mild temperament and relatively small body size of these animals make them excellent candidates for the treatment of orthopaedic problems (Kaneps 1996).This short communication describes the clinical presenta-tion and surgical treatment of recurrent lateral luxation of the shoulder in an alpaca by greater tubercle osteotomy and bicipital tendon transposition, using a technique previously described in dogs (Hohn and others 1971, Piermattei 1997, Engen 1998, Talcott and Vasseur 2003).A four-year-old male alpaca, bodyweight 60 kg, had a history of recurrent luxation of the shoulder. The initial lux-ation had occurred seven months previously, after a fight with another male alpaca. The luxated joint was easily reduced under sedation using 6 mg (0·1 mg/kg) xylazine (Rompun; Bayer), and the animal was reported be sound between each episode.On examination, the alpaca did not show any lameness at the walk, and manipulation of the shoulder was not resented in extension or flexion. There was no swelling or thickening of the soft tissues. Lateral luxation was easily induced manu-ally, resulting in a non-weight-bearing lameness, but any lux-ation could be easily reduced without sedation. Craniocaudal and lateromedial radiographs of the shoulder were taken in sternal and lateral recumbency, respectively. There were no visible osteoarthritic or other changes affecting the shoulder joint with the joint reduced.The alpaca was not allowed food for 24 hours before surgery, and water was withheld for at least eight hours. After place-ment of a 14 G catheter into the right jugular vein (Intraflon 2; Vygon), 6 mg xylazine was administered intravenously to sedate the animal. Anaesthesia was induced with 140 mg (2·3 mg/kg) ketamine (Ketaset; Fort Dodge Animal Health) and 5 mg (0·08 mg/kg) diazepam (Diazepam; Hameln Pharmaceuticals), administered intravenously. The alpaca became recumbent, but needed additional increments of ket-amine, as well as the local application of lidocaine (Xylocaine Spray; Astra) on to the larynx, to facilitate intubation of the trachea using a cuffed endotracheal tube with an inter-nal diameter of 7·5 mm. Anaesthesia was maintained with sevoflurane (SevoFlo; Abbott) in 100 per cent oxygen, admin-istered via a small animal circle breathing system. Flunixin (60 mg) (Meflosyl; Fort Dodge Animal Health) and 6 mg morphine (Morphine Sulfate; Celltech) were administered 10 ml/kg/hour Hartmann’s solution intravenously through-out the period of anaesthesia.The alpaca was positioned in right lateral recumbency. After the usual aseptic precautions, a craniolateral para-humeral incision was made, beginning 6 cm dorsal to the shoulder joint and extending to a point midway down the humeral shaft. The skin and subcutaneous tissues were then reflected, and the lateral border of the brachiocephalic mus-cle was retracted medially, exposing the cranial aspect of the proximal humerus and the insertions of the supraspinatus, deltoid and superficial and deep pectoral muscles (Fig 1). The insertion of the superficial pectoral muscle was transected. The tissues over the bicipital groove and the intertubercular ligament were incised. The biceps tendon was freed from the surrounding fascia by blunt dissection proximally, and the muscle body was separated from surrounding tissue distally.Two holes were drilled through the greater tubercle, 1·5 cm apart, using a 2 mm drill bit perpendicular to the humerus axis, exiting on its medioproximal aspect. The glid-ing holes were enlarged with a 3·5 drill bit to a depth of 1·5 cm. The pilot hole was drilled with a 2·5 mm drill bit through the opposite cortex. A depth gauge was used to obtain the correct length of screw before tapping the pilot hole with a 3·5 tap. Two 3·5 mm cortical screws, 4·8 and 5·5 cm long, were driven in place to assess correct positioning and length, and they then were removed. A 7 mm thick osseous flap, 2·5 cm long and 1·5 cm wide, was made with an oscillating saw from the greater tubercle, to include the insertion of the supraspinatus muscle. The flap was retracted and separated proximally from the surrounding tissues by blunt dissection (Fig 2).The bicipital tendon was transposed laterally and the bone flap from the greater tubercle was fixed in position with the screws (Fig 3). The wound was flushed with saline. The brachiocephalic muscle was reattached and the subcutane-ous tissues were closed in a simple continuous pattern with 2·0 braided lactomer (Polysorb 2.0; Syneture). The skin was closed with simple interrupted sutures of polypropylene (Prolene 0; Ethicon). A stent bandage was applied on the skin. The alpaca was placed into sternal recumbency with its head held up and blankets were used to treat the hypother-mia (rectal temperature 35·7°C at the end of the pro cedure). The endotracheal tube was removed once the animal’s swallowing reflex returned, but the head was kept supported in an elevated position until full consciousness was achieved. A moderate bloat developed during the procedure, but it resolved once the animal was placed into sternal recum-bency and no reflux was observed. A dose of 6 mg morphine intramuscularly, followed by 0·6 mg (0·01 mg/kg) buprenor