Fecal Shedding of Salmonella in Horses Admitted to a Veterinary Teaching Hospital

Fecal samples were collected from 724 horses admitted to, and 232 horses hospitalized at, a veterinary teaching hospital between October 2000 and June 2001, and cultured for Salmonella. Salmonella was isolated on 24 occasions from 12 horses. S. Newport was the most commonly isolated serotype. The estimated prevalence (95% confidence interval [CI]) of Salmonella shedding on admission was 0.5% (0.1, 2.0). The estimated incidence rate of Salmonella shedding during hospitalization was 4.3% (95% CI, 2.2-8.1). The highest incidence of Salmonella shedding during hospitalization occurred during June 2001, but no significant (P > .5) temporal clusters of horses shedding Salmonella were detected.Horses shed Salmonella in their feces at a low rate. Horses shedding Salmonella occurred only sporadically and no obvious serotype pattern was observed. The occurrence of fecal shedding probably reflected the prevalence of inapparent Salmonella infection in the hospital source population, providing a baseline against which future potential outbreaks can be identified.

Introduction

Infection of horses by Salmonella organisms is a serious health issue. It is particularly troubling when outbreaks occur in hospitalized patients because these outbreaks can result in substantial economic losses and have a major impact on the welfare of patients.[1] Establishments with a high-density of horses, including veterinary teaching hospitals (VTHs) and private veterinary clinics, [1 and 2] are most vulnerable to outbreaks of disease attributable to Salmonella infection. Host susceptibility and environmental persistence of Salmonella are also factors contributing to outbreaks.Estimates of the prevalence of Salmonella-shedding horses admitted to veterinary hospitals have generally been made under outbreak conditions.[1] For example, between 1971 and 1982, 245 hospitalized horses (1.7%) at the University of California were found to shed Salmonella.[3 and 4] Three major outbreaks occurred during the study period, with no apparent periodicity. Between 1996 and 1999, 35 hospitalized horses (5.5%) at the Michigan State University were found to shed Salmonella.[5] One major outbreak occurred during the study period. Only one national survey of nonhospitalized horses in the United States for Salmonella infection has been undertaken: the prevalence of fecal shedding of Salmonella was estimated to be 0.8%, and the farm prevalence of shedding was 1.8%.[6]Many factors have been associated with the risk of Salmonella isolation from hospitalized horses, including diarrhea, fever, change in diet, large colon impaction, colic, withholding feed, feeding bran mash, antibiotic treatment, intubation with nasogastric tubes, and average daily ambient temperature.[7, 8, 9 and 10] Many of theses factors are thought to operate primarily through the effect of stress, increasing the susceptibility of horses to infection. Also, if a horse is infected by Salmonella but not shedding the organisms in its feces, the presence of stressors may reactivate fecal shedding. Most studies that have been conducted on risk factors for Salmonella shedding in horses have included horses with clinical salmonellosis, with or without inclusion of horses inapparently infected by Salmonella.[7, 8 and 10] Risk factors for Salmonella fecal shedding versus clinical salmonellosis have not been clearly delineated.An outbreak (epidemic) of disease can be defined as “an occurrence of disease in excess of its anticipated frequency.”[11] To more effectively identify future outbreaks of Salmonella infection in hospitalized horses, it is necessary to have accurate estimates of the prevalence of endemic fecal shedding of Salmonella in horses admitted to VTHs, and the incidence of fecal shedding during hospitalization. The aims of this study were to estimate the prevalence of fecal shedding in horses admitted to a VTH, to estimate the incidence of fecal shedding during hospitalization, and to describe the seasonal distribution of fecal Salmonella-shedding prevalence and incidence.

Materials and Methods

Study Design

Fecal samples were collected from horses admitted to the Purdue University VTH between October 12, 2000 and June 30, 2001. Horses admitted as inpatients were sampled at least on the day of admission, the day after admission, the day of discharge, and once or more in between. All horses admitted to the VTH during the study period were eligible to be sampled. In the case of mares accompanying sick foals, samples were also collected from the mare. Fecal samples were collected generally from freshly voided fecal material in stalls. Samples were stored at 4°C for up to 24 hours before processing.

Data Collection

For all horses included in the study, date of examination (outpatients) or date of hospitalization (inpatients) was recorded. For inpatients, date of discharge or date of death was also recorded. Horse characteristics were recorded as part of each horse's medical record, and included date of birth, sex (mare, stallion, gelding), and specific breed. The outcome of each admission (discharged alive, died, euthanized) and whether a necropsy was performed were also recorded. The number of samples collected per horse was recorded in a laboratory-reporting system, but specific date of collection of each sample (except for the first and last samples collected) was not routinely recorded.

Bacteriologic Cultures

All fecal samples were cultured for Salmonella species using standard techniques. Specimens were streaked onto brilliant green (BG) and xylose-lysine-tergitol (XLT-4) plates, and approximately 10 g of fecal material was put into 100 mL of tetrathionate Hajna broth. BG plates were incubated at 35° to 37°C for 18 to 24 hours and XLT-4 plates were incubated for 24 to 48 hours. Tetrathionate broth was incubated at 35° to 37°C for 24 to 48 hours, and then streaked to BG and XLT-4 plates. These plates were incubated as previously described. Suspect colonies on plates were subcultured and further identified by the Vitek GNI system. All Salmonella isolates were speciated and serotyped (National Veterinary Services Laboratory, Ames, Ia).

Data Analysis

The total number of horses examined (admissions), the total number of examinations (including admissions), the total number of horses hospitalized during the study period, and the number of samples collected per horse were calculated (Excel 2000, Microsoft Corp, Redmond, Wash) from recorded information. The frequency distributions of admissions (1-6) per horse, sex, breed, and patient outcome were calculated based on owner/horse identity and hospital record number, and the frequency distribution of number of samples collected per horse (nil to 8) was calculated from laboratory records and owner/horse identification and laboratory submission number. Length of hospitalization (days) was calculated from recorded date of hospitalization and date of discharge information, and was summarized by median and mean lengths of hospitalization and 95% confidence intervals (CIs), based on the Wilcoxon test (Minitab for Windows, Minitab Inc, State College, Penn) and the normal distribution (Statistix for Windows, Analytical Software, Tallahassee, Fla), respectively. Normality of the distributions of lengths of hospitalization and age were tested using the normal probability plot and Wilks-Shapiro statistic (Statistix).To estimate the incidence of Salmonella shedding, only hospitalized horses that were sampled on at least three occasions were included, because the sensitivity of culture is suboptimal and repeated attempts to culture Salmonella are necessary to increase the sensitivity of this technique.[12] The total number of days at-risk of shedding Salmonella was calculated as the sum of lengths of hospitalization. The incidence density rate (true incidence) of Salmonella shedding was calculated as

(No. horses detected shedding Salmonella)/(total No. horse-days at-risk)

and expressed as the number of horses shedding Salmonella per 1000 horse-days at-risk. For example, if 10, 10, and 30 horses were hospitalized for periods of 3, 6, and 9 days each, horse-days at-risk would be (10.3)+(10.6)+(30.9) = 360. If one case of Salmonella-shedding was detected in this group, the estimated incidence density rate would be one per (1000/360) 1000 horse-days AT-RISK = 2.8 per 1000 horse-days at-risk. Horses that were culture-positive on the first sampling were not considered incident cases of Salmonella-shedding, and therefore were not included in the numerator of the incidence density rate. Horses shedding Salmonella after hospitalization were assumed to have commenced shedding at the midpoint of their hospitalization, and therefore contributed half their length of hospitalization to the rate denominator. A 95% CI for the estimated incidence density rate was calculated assuming shedding Salmonella to be Poisson distributed.[13] Incidence-density rates were also calculated for each month of the study, the contribution of each horse to each month's horse-days at-risk being calculated on the basis of date of hospitalization and date of discharge information. Cumulative incidence (risk) rate (%) was calculated as described for the incidence density rate, except that the denominator used was the number of horses at-risk of Salmonella-shedding when hospitalized. For cumulative incidence rate, a 95% CI was calculated based on the binomial distribution.[14]The prevalence of Salmonella-shedding in horses admitted to the VTH was calculated as

(No. horses detected shedding Salmonella by culturewhen admitted)/(total No. horses admitted and sampled)

Ninety-five percent CIs for prevalence estimates were calculations based on the binomial distribution.[14]The temporal clustering of horses shedding Salmonella was investigated using the scan statistic.[15] For horses shedding Salmonella after hospitalization, the midpoint of their length of hospitalization was used as the date of first occurrence of Salmonella-shedding. The population at-risk used in these analyses was the monthly total number of horse-days at-risk. The occurrence of horses shedding Salmonella was assumed to be Poisson distributed, so the expected number of horses shedding Salmonella in any given time period was proportional to the incidence of Salmonella-shedding during the entire study period. The study period was scanned for clusters of horses shedding Salmonella using a scanning window of as much as 50% (130 days) of the time period (SatScan, Bethesda, Md).

Results

Between October 12, 2000 and June 30, 2001, 724 horses were admitted to the VTH. Six hundred and thirty-two horses (87.3%) were admitted only once during the study period; 69 (9.5%), 15 (2.1%), 2 (0.3%), 5 (0.7%), and 1 (0.1%) horses were admitted on 2, 3, 4, 5, and 6 separate occasions, respectively. Length of hospitalization was not recorded for 2 horses. Three-hundred and sixty (42.3%) of the 854 admissions performed did not result in hospitalization of the horse. The distribution of length of hospitalization of all horses hospitalized during the study is shown in Figure 1. The median and mean lengths of hospitalization (95% CI) were 3.0 (2.5, 3.5) and 4.3 (3.8, 4.7) days, respectively. The minimum and maximum lengths of hospitalization were 1 and 57 days. The distribution of lengths of stay was nonnormally distributed (Wilks-Shapiro statistic, 0.7317).     

Association of admission plasma D-dimer concentration with diagnosis and outcome in horses with colic

Background: Coagulopathies detected in horses with gastrointestinal problems seem to be associated with poor outcome. Plasma D‐Dimer concentration is a sensitive test for assessing coagulopathies. Hypothesis: Plasma D‐Dimer concentration tested on admission is related to diagnosis and outcome in horses with colic. Animals: Four hundred and ninety three horses referred for evaluation of abdominal pain. Methods: Prospective observational clinical study. Horses were grouped according to diagnosis (medical and surgical intestinal obstructions, ischemic disorders with and without intestinal resection, enteritis, peritonitis), outcome (survivors, nonsurvivors), and number of coagulopathies (normal profile, 1 or 2 coagulopathies, subclinical disseminated intravascular coagulation [DIC]). Blood samples were collected on admission and plasma D‐Dimer concentration, clotting times (PT and aPTT), and antithrombin activity were determined. Positive likelihood ratios (LR+) were calculated for evaluation of D‐Dimer cut‐off values, which were later tested in a logistic regression model. Results: Horses with enteritis or peritonitis had significantly (P < .001) higher plasma D‐Dimer concentrations and more severe coagulopathies on admission than horses with other diagnoses. Nonsurvivors also had significantly (P < .001) higher plasma D‐Dimer concentrations at presentation than did survivors, and those horses with subclinical DIC on presentation had an odds ratio (OR) 8.6 (95% confidence interval [CI], 3.3–22.5, P < .001) for nonsurvival. Finally, D‐Dimer concentrations >4,000 ng/mL had a LR+ of 5.9 and an OR 8.8 (95% CI, 4.5–17.1, P < .001) for nonsurvival. Conclusion and Clinical Importance: Plasma D‐Dimer concentration measured on admission can be used to facilitate diagnosis and outcome prediction in horses with colic. A potential cut‐off value for nonsurvival was found at approximately 4,000 ng/mL.     

Outcome of Adult Horses with Botulism Treated at a Veterinary Hospital: 92 Cases (1989–2013)

Background

There are no studies evaluating a large population of adult horses treated for botulism. Reported survival rates in outbreak situations are low; however, many horses in outbreaks do not receive treatment.

Hypothesis/Objectives

That adult horses treated at a veterinary hospital would have improved survival compared to outbreak situations. Additional aims included identification of predictors of nonsurvival.

Animals

All horses greater than 6 months of age with a final diagnosis of botulism admitted to a veterinary teaching hospital between 1989 and 2013 were included.

Methods

Retrospective study. Historical, admission, and hospitalization data were retrieved from medical records and associations between variables and nonsurvival were identified using logistic regression. Two multivariable models were developed pertaining to (1) information available at admission and (2) clinical findings during hospitalization.

Results

Ninety‐two records met inclusion criteria. Retained variables for the two models indicated that higher rectal temperature (OR, 1.94; CI, 1.19–3.17) and dysphagia (OR, 4.04; CI, 1.01–16.17) observed at admission increased the odds of survival, as did treatment with antitoxin (OR, 121.30; CI, 9.94–1,480.65). Horses with abnormal respiratory effort or inability to stand had decreased odds of survival. Overall survival was 48% but was significantly higher (67%, P = .011) for horses that arrived standing, and even higher (95%, P < .001) for horses that remained able to stand throughout hospitalization. Complications occurred in 62% of horses but were not associated with nonsurvival.

Conclusions and Clinical Importance

Horses that lose the ability to stand have a poor chance of survival. Complications are common in treated horses but do not reduce survival.     

Survival of horses following strangulating large colon volvulus

Reasons for performing study: The pattern of long‐term survival and specific factors associated with long‐term survival have not previously been evaluated in horses with a strangulating large colon volvulus (LCV). Objectives: To provide data on the long‐term survival of horses with LCV and to identify pre‐, intra‐ and post operative variables associated with survival. Methods: Clinical data and long‐term follow‐up information were obtained from 116 horses with a strangulating LCV (≥360°) undergoing general anaesthesia. Two multivariable Cox proportional hazards models for post operative survival time were developed: Model 1 included all horses and evaluated preoperative variables and Model 2 included horses that survived anaesthesia and evaluated pre‐, intra‐ and post operative variables. Results: The study population comprised 116 horses. Eighty‐nine (76.7%) survived general anaesthesia. Of these, the percentage that survived until discharge, to one year and to 2 years was 70.7%, 48.3% and 33.7%, respectively. Median survival time for horses that survived general anaesthesia was 365 days. In Model 1 increased preoperative packed cell volume (PCV) was significantly associated with reduced post operative survival (hazard ratio [HR] 1.08, 95% confidence interval [CI] 1.05–1.11). However, this effect changed over time. In Model 2 abnormal serosal colour intraoperatively (HR 3.61, 95% CI 1.55–8.44), increased heart rate at 48 h post surgery (HR 1.04, 95% CI 1.02–1.06), and colic during post operative hospitalisation (HR 2.63, 95% CI 1.00–6.95), were all significantly associated with reduced post operative survival. Conclusions: Survival time in horses with a LCV was associated with preoperative PCV, serosal colour, heart rate at 48 h post operatively and colic during post operative hospitalisation. Potential relevance: This study provides evidence‐based information on the long‐term survival of horses with LCV and identifies parameters that may assist decision‐making by clinicians and owners.     

Factors associated with Salmonella shedding among equine colic patients at a veterinary teaching hospital

OBJECTIVE: To evaluate factors potentially associated with fecal Salmonella shedding among equine patients hospitalized for colic at a veterinary teaching hospital and to determine the effects of probiotic treatment on fecal Salmonella shedding and clinical signs. DESIGN: Longitudinal study and controlled trial. ANIMALS: 246 equine colic patients. PROCEDURE: History and medical information were obtained from patient records. Fecal and environmental samples were submitted for aerobic bacterial culture for Salmonella enterica. Fifty-one patients were treated with a commercially available probiotic; 46 were treated with a placebo. Logistic regression was used to evaluate data. RESULTS: Salmonella organisms were detected in feces from 23 (9%) patients at least once during hospitalization. Patients were more likely to shed Salmonella organisms if diarrhea was evident < or = 6 hours after hospitalization and duration of hospitalization exceeded 8 days (odds ratio [OR], 20.3), laminitis developed during hospitalization (OR, 12.0), results of nasogastric intubation were abnormal (OR, 4.9), leukopenia was evident < or =6 hours after hospitalization (OR, 4.6), or travel time to the teaching hospital exceeded 1 hour (OR, 3.5). Horses treated with the probiotic did not differ from control horses in regard to likelihood of fecal Salmonella shedding (OR, 1.5) or prevalence of clinical signs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that certain risk factors are associated with fecal shedding of S enterica among equine patients hospitalized at a veterinary teaching hospital because of colic and that pathogen monitoring in patients and the hospital environment and use of barrier nursing precautions for equine colic patients are beneficial.     

Hypomagnesemia in hospitalized horses

This study was initiated to identify the signalment and clinical variables potentially associated with hypomagnesemia in horses evaluated at the North Carolina State University, College of Veterinary Medicine (NCSU-CVM) veterinary teaching hospital between January 1999 and May 2001. A nested case reference study (nested case-control study) was conducted to examine the potential relationship between hypomagnesemia and signalment, serum chemistry panel analyses, number of hospitalization days, discharge status, and diagnosis. A series of independent and multivariable logistic regression models were used to assess the potential association of each variable with low total serum magnesium concentrations. Four hundred one of 823 (48.7%) horses had serum total magnesium concentrations below the normal reference range. Hypomagnesemia was more likely to occur in horses older than I month of age. Colic (odds ratio [OR]: 2.96, 95% confidence intervals [CI]: 2.14-4.08), acute diarrhea (OR: 5.91, 95% CI: 2.32-15.06), other gastrointestinal disease (OR: 2.07, 95% CI: 1.15-3.71), infectious respiratory disease (OR: 5.07, 95% CI: 2.09-12.28), and multiorgan system disease (OR: 2.31, 95% CI: 1.24-4.28) were associated with hypomagnesemia in adult horses, whereas foals with diarrhea (excluding septic foals) (OR: 0.11, 95% CI: 0.01-0.84) were less likely to have hypomagnesemia. Overall, there was no relationship between hypomagnesemia and mortality (OR: 1.00, 95% CI: 0.72-1.41), but horses with colic and hypomagnesemia were less likely to die than horses with colic and normal or high total magnesium (OR: 0.53, 95% CI: 0.30-0.95). Among horses that survived, hypomagnesemia at admission was associated with a longer hospitalization period (OR: 1.45, 95% CI: 1.00-2.11).     

Physicochemical Interpretation of Acid‐Base Abnormalities in 54 Adult Horses with Acute Severe Colitis and Diarrhea

Background

The quantitative effect of strong electrolytes, pCO₂, and plasma protein concentration in determining plasma pH and bicarbonate concentrations can be demonstrated with the physicochemical approach. Plasma anion gap (AG) and strong ion gap (SIG) are used to assess the presence or absence of unmeasured anions.

Hypotheses

The physicochemical approach is useful for detection and explanation of acid‐base disorders in horses with colitis. AG and SIG accurately predict hyperlactatemia in horses with colitis.

Animals

Fifty‐four horses with acute colitis and diarrhea.

Methods

Retrospective study . Physicochemical variables were calculated for each patient. ROC curves were generated to analyze sensitivity and specificity of AG and SIG for predicting hyperlactatemia.

Results

Physicochemical interpretation of acid‐base events indicated that strong ion metabolic acidosis was present in 39 (72%) horses. Mixed strong ion acidosis and decreased weak acid (hypoproteinemia) alkalosis was concomitantly present in 17 (30%) patients. The sensitivity and specificity of AG and SIG to predict hyperlactatemia (L‐lactate > 5 mEq/L) were 100% (95% CI, 66.4–100; P < .0001) and 84.4% (95% CI, 70.5–93.5 P < .0001). Area under the ROC curve for AG and SIG for predicting hyperlactatemia was 0.95 (95% CI, 0.86–0.99) and 0.93 (95% CI, 0.83–0.99), respectively.

Conclusion and Clinical relevance

These results emphasize the importance of strong ions and proteins in the maintenance of the acid‐base equilibria. AG and SIG were considered good predictors of clinically relevant hyperlactatemia.     

Risk Factors for Equine Postoperative Ileus and Effectiveness of Prophylactic Lidocaine

Background: Postoperative ileus (POI) is a frequent and often fatal complication of colic surgery. Reliably effective treatments are not available.
Objectives: To determine risk factors and protective factors associated with POI, and to assess the effect of lidocaine IV on short-term survival.
Animals: One hundred and twenty-six horses that underwent small intestinal colic surgery and that survived for at least 24 hours postoperatively.
Methods: Retrospective cross-sectional study. The association of 31 pre-, intra-, and postoperative variables with POI and the association of lidocaine treatment with short-term survival were investigated. Associations were evaluated with univariable logistic regression models, followed by multivariable analysis.
Results: Significant associations of high heart rate (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.03–1.08), the presence of more than 8 L of reflux at admission (OR = 3.02, 95% CI 1.13–8.02) and the performance of a small intestinal resection (OR = 2.46, 95% CI 1.15–5.27) with an increased probability of POI were demonstrated. Prophylactic lidocaine treatment was significantly associated with a reduced incidence of POI (OR = 0.25, 95% CI 0.11–0.56). Lidocaine treatment was also significantly associated with enhanced short-term survival (OR = 0.30, 95% CI 0.09–0.98).
Conclusions and Clinical Importance: The variables associated with an increased risk of POI can be useful in identifying horses at risk of POI and in providing a more accurate prognosis. The results are supportive for lidocaine IV as an effective prokinetic treatment after small intestinal colic surgery.     

A farm-based prospective study of equine colic incidence and associated risk factors

Abdominal pain (colic) in the horse is one of the most acute problems facing equine practitioners. Several causes and risk factors are associated with colic. The current study evaluated the incidence and associated risk factors of colic during a 1-year evaluation in horse farms of Kerman, Iran. The study investigated age, sex, breed, anthelmintic control program, and nutritional status of 128 horses of four breeds on six farms that took part in the study. The mean incidence density rate of colic in the horse population was 8.6% (11/128) in a year. Crossbred horses had more chance of developing colic (P < .05). Horses between the ages of 2 and 10 years also had more risk of developing colic (P < .05). There was no significant difference between sexes (P < .05), and nutritional factors were the most associated risk factors in the cases under study.     

Plasma endotoxin in horses presented to an equine referral hospital: correlation to selected clinical parameters and outcomes

Reasons for performing study: Endotoxaemia is frequently presumed on the basis of clinical signs in horses with colic. Objective: Measurements of plasma endotoxin (LPS) are rarely made in clinical cases and there is little information on the correlations between this variable, clinical variables and outcomes. Objectives: To measure LPS levels in plasma of horses presented to the Philip Leverhulme Equine Hospital on admission and daily for up to 4 days and to relate LPS levels to selected clinical parameters, such as heart rate and packed cell volume, and outcomes. Methods: Blood samples were collected and stored at ‐20°C prior to assay of the plasma using a validated kinetic chromogenic Limulus amoebocyte lysate (LAL) assay. Clinical parameters and outcome variables were collected from hospital records. Associations were determined by Chi‐squared test and logistic regression analysis. Results: Daily blood samples were collected from 234 horses. LPS was detected in 26.5% of the study population and in 29% of those horses presented for colic. Horses providing samples with detectable LPS were more likely to die whilst in the hospital than those that did not (P = 0.045). Horses presenting with colic were more likely to have detectable LPS in their plasma than noncolic cases (P = 0.037), although LPS was detected in the plasma of 8 out of 42 noncolic horses. A horse that did not meet the study definition of clinical endotoxaemia was 10 times less likely to provide a positive LPS sample (OR 0.10, 95% CI: 0.05–0.22). Conclusions: The proportion of horses providing samples with detectable LPS was similar to other studies. Potential relevance: LPS was detected in the minority of horses presented with colic. Increased levels of LPS positively correlated with packed cell volume and with risk of mortality in colic cases.     

Risk factors associated with self-reported Q fever in Australian wildlife rehabilitators: Findings from an online survey

Australian wildlife rehabilitators (AWR) are at increased risk of developing Q fever, a serious zoonotic disease caused by the intracellular bacterium Coxiella burnetii. Previous studies have suggested that Australian wildlife may be a potential C. burnetii infection source for humans. However, a recent serological survey of AWR found no association between C. burnetii exposure and direct contact with any wildlife species. To further explore the potential risk that wildlife may pose, this study aimed to identify associations between self-reported Q fever in AWR and risk factors for exposure to C. burnetii. An online cross-sectional survey was implemented in 2018 targeting AWR nationwide. Risk factors for self-reported Q fever were determined using multivariable logistic regression. Medically diagnosed Q fever was self-reported in 4.5% (13/287) of unvaccinated respondents. Rehabilitators who self-reported medically diagnosed Q fever were significantly more likely to: primarily rehabilitate wildlife at a veterinary clinic (OR 17.87, 95% CI: 3.09–110.92), have domestic ruminants residing on the property where they rehabilitate wildlife (OR 11.75, 95% CI: 2.91–57.42), have been educated at a High School/Technical and Further Education level (OR 10.29, 95% CI: 2.13–84.03) and be aged >50 years (OR 6.61, 95% CI: 1.60–38.35). No association was found between self-reported Q fever and direct contact with wildlife. These findings support previous work suggesting that AWR are at increased risk of C. burnetii infection and may develop Q fever potentially via exposure to traditional infection sources including livestock, other domestic animals, or contaminated environments, in association with their rehabilitation practices and lifestyle. Although Q fever vaccination is recommended for AWR, vaccine uptake is low in this population. Future studies should aim to determine the level of Q fever awareness and identify barriers to Q fever vaccination in this at-risk group. The difficulty in accessing the AWR population also highlights the need for a national centralized AWR database.     

A pilot study of the effects of acupuncture treatment on objective and subjective gait parameters in horses

Objectives

To investigate whether acupuncture can alter gait in horses as assessed by objective and subjective parameters.

Demographic,preoperative and anaesthesia-related risk factors for unsatisfactory recovery quality in horses undergoing emergency abdominal surgery

ObjectiveTo determine demographic, preoperative and anaesthesia-related variables that may be associated with unsatisfactory recovery quality in horses undergoing emergency abdominal surgery (colic) in an equine teaching hospital.Study designRetrospective case series.AnimalsA total of 313 horses.MethodsThe anaesthetic records of horses admitted for surgical treatment of colic between 2005 and 2018 were examined. Overall quality of recovery was assessed as dangerous, poor, fair, good or excellent. The following categories were constructed as a dichotomic variable: unsatisfactory recovery (poor and dangerous recoveries) and satisfactory recovery (excellent, good and fair recoveries). Univariable and multivariable analyses were performed to evaluate the association between all studied variables and recovery.ResultsAll recoveries were unassisted. Unsatisfactory recovery quality totalled 17.2% (3.5% and 13.7% were dangerous and poor recoveries, respectively), whereas satisfactory recoveries totalled 82.8% (26.2%, 40.9% and 15.7% were fair, good and excellent recoveries, respectively). Univariable analysis showed that unsatisfactory recoveries were associated with high preoperative packed cell volume, pain behaviour, poor premedication and induction quality, high intraoperative mean heart rate, low mean arterial blood pressure, dobutamine dose ≥1.5 μg kg^–1 minute^–1, non-administration of romifidine, long anaesthesia time and prolonged time to stand. The multivariable model showed that factors strongly associated with unsatisfactory recovery quality were dobutamine dose ≥1.5 μg kg^–1 minute^–1 [adjusted odds ratio (AOR) = 6.60; 95% confidence interval (CI), 2.91–14.96], poor premedication quality (AOR=4.60; 95% CI, 1.73–12.23) and a time to stand > 70 minutes (AOR=2.59; 95% CI, 1.13–5.91).Conclusions and clinical relevanceOur study shows that high dobutamine requirements, poor premedication quality and a prolonged time to stand are risk factors for unsatisfactory recovery quality in horses undergoing anaesthesia for colic surgery. Addressing these factors may enable clinicians to improve the quality of recovery phase.     

Prognostic Value of Cardiac Troponin I and L‐Lactate in Blood of Dairy Cows Affected by Downer Cow Syndrome

Background

The downer cow syndrome (DCS) is a challenging health issue in the dairy industry. No cow‐side test is available to provide an accurate prognosis for DCS cases in farm settings.

Hypothesis/Objectives

Local or systemic hypoperfusion and myocardial lesions lead to an increase in blood concentration of biomarkers cardiac troponin I (cTnI) and L‐lactate. The objective was to determine the prognostic values of these biomarkers assessed cow‐sides in addition to clinical examinations in prognostication of a negative outcome (NO: death or euthanasia within 7 days).

Animals

218 client‐owned dairy cows affected by DCS.

Methods

In a prospective study, animals were monitored for 60 days after inclusion of each cow. Blood cTnI and L‐lactate concentrations were measured on the day of inclusion. The prognostic accuracy of both biomarkers and physical examination variables was estimated to predict NO. A mixed multivariable logistic regression model was used for data analysis.

Results

Prevalence of NO in this study was 63% on day 7. Troponin concentrations greater than 0.7 ng/mL had sensitivity and specificity of 54.1% (95% CI: 45.3–62.7%) and 78.4% (95% CI: 67.3–87.1%), respectively, for predicting NO. Blood L‐lactate was not associated with the outcome. The multivariable model revealed that heart rate >100 bpm (OR; 95% CI: 3.7; 1.3–10.2) and cTnI > 0.7 ng/mL (OR; 95% CI: 5.5; 2.1–14.6) were associated with the risk of NO.

Conclusions and Clinical Importance

Hypertroponinemia and tachycardia were associated with reduced survival in DCS cases. The use of cow‐side blood cTnI concentrations and heart rate could help to rapidly identify cows in farm setting that have poor chances of recovery and would benefit from a more aggressive treatment or euthanasia.     

Cortisol Circadian Rhythm Ratio: A Simple Method to Detect Stressed Horses at Higher Risk of Colic?

With the hypothesis that police horses with abnormal cortisol circadian rhythm (CCR) had more chance to develop colic, the aim of this study was to determine the CCR ratio in horses subjected to different housing and work conditions and to associate abnormal CCR ratio with incidence of colic. A total of 116 police horses belonging to four different groups were studied. In all, 31 were full-time stabled and performed urban patrolling activity, 27 were full-time stabled and performed equine therapy and sports activities, 25 were part-time stabled and performed urban patrolling, and 33 animals were kept full-time on pasture and did not perform any kind of work activity. Venous blood samples were collected between 6 and 7 am and also 8 hours later, and cortisol concentrations were determined by radioimmunoassay to calculate the CCR ratio. Annual colic incidences (6 months before and after the day on which CCR ratio was determined) were assessed by examining individual medical files. The overall incidence of abnormal CCR ratio (<0.30) was 63.3%, and 107 cases of colic were reported for this population with a mean incidence of 0.92 colic/horse/yr. Horses with abnormal CCR had 2.3 times more chance to have colic (95% CI: 1.07 to 5.28, P = .03) when compared with those with normal CCR. In conclusion, high incidence of abnormal CCR ratio indicates that police horses were under stressful conditions. Horses with abnormal CCR ratios were more prone to suffer colic episodes, indicating that CCR ratio determination could perhaps be useful in detecting horses at risk of colic.     

Prevalence of and Risk Factors for Degenerative Mitral Valve Disease in Dogs Attending Primary‐care Veterinary Practices in England

Background

To date, epidemiological studies on degenerative mitral valve disease (DMVD) in dogs have largely reported referral caseloads or been limited to predisposed breeds. Analysis of primary‐care data to identify factors associated with DMVD would help clinicians identify high‐risk individuals and improve understanding.

Objectives

To estimate the prevalence of and identify risk factors for DMVD in dogs attending primary‐care veterinary practices in England.

Animals

Cases were identified within the electronic patient records of 111,967 dogs attending 93 practices. Four hundred and 5 dogs were diagnosed with DMVD (diagnosed cases) and a further 3,557 dogs had a heart murmur (HM) consistent with DMVD (possible cases).

Methods

Retrospective cross‐sectional study design. Prevalence was adjusted for the sampling approach. Mixed effects logistic regression models identified factors associated with DMVD.

Results

Prevalence estimates of diagnosed DMVD and HMs consistent with DMVD (both diagnosed and possible cases) were 0.36% (95% confidence interval [CI]: 0.29–0.45) and 3.54% (95% CI: 3.26–3.84) respectively. In the multivariable analysis, males had higher odds of diagnosed DMVD than did females (odds ratio [OR] 1.40, 95% CI: 1.12–1.74). Insured dogs had increased odds of DMVD compared with noninsured dogs (OR 3.56, 95% CI: 2.79–4.55) and dogs ≥20 kg had approximately half the odds of DMVD diagnosis compared with dogs <20 kg (OR 0.51, 95% CI: 0.36–0.74). Strong associations between a DMVD diagnosis and individual breeds and age were identified.

Conclusions and Clinical Importance

Degenerative mitral valve disease was a common disorder in practice‐attending dogs. Knowledge of identified risk factors for DMVD could improve clinical diagnosis and direct future research.     

Molecular screening and risk factors of enterotoxigenic Escherichia coli and Salmonella spp. in diarrheic neonatal calves in Egypt

The aim of the present study was to carry out molecular epidemiological investigation on enterotoxigenic Escherichia coli (ETEC) K99 and Salmonella spp. in diarrheic neonatal calves. Fecal samples were obtained from 220 diarrheic calves at 9 farms related to four governorates in central and northern Egypt. E. coli and Salmonella spp. isolates were examined for E. coli K99 and Salmonella spp. using PCR. ETEC K99 was recovered from 20 (10.36 %) out of 193 isolates, whereas Salmonella spp. was recovered from nine calves (4.09%).Multivariable logistic regression was used to evaluate the risk factors associated with both infections. ETEC K99 was significantly affected by age (P < 0.01; OR: 1.812; CI 95%: 0.566–1.769), colostrum feeding practice (P < 0.01; OR: 5.525; CI 95%: 2.025–15.076), rotavirus infection (P < 0.001; OR: 2.220; CI 95%: 0.273–1.251), vaccination of pregnant dams with combined vaccine against rotavirus, coronavirus and E. coli (K99) (P < 0.001; OR: 4.753; CI 95%: 2.124–10.641), and vitamin E and selenium administration to the pregnant dam (P < 0.01; OR: 3.933; CI 95%: 0.703–1.248).Infection with Salmonella spp. was found to be significantly affected by the animal age (P < 0.05; OR: 0.376; CI 95%: 0.511–1.369), Hygiene (P < 0.05; OR: 0.628; CI 95%: 1.729–5.612), and region (P < 0. 01; OR: 0.970; CI 95%: 0.841–1.624).The results of the present study indicate the importance of PCR as rapid, effective and reliable tool for screening of ETEC and Salmonella spp. when confronted with cases of undifferentiated calf diarrhea. Moreover, identification of the risk factors associated with the spreading of bacteria causing diarrhea may be helpful for construction of suitable methods for prevention and control.     

Prevalence of enteric non‐typhoidal Salmonella in humans in the Middle East and North Africa: A systematic review and meta‐analysis

To enhance efforts related to controlling foodborne pathogens in the Middle East and North Africa (MENA), information on epidemiology of non‐typhoidal Salmonella enterica (hereafter termed “Salmonella”) is limited. We quantified the overall regional and country‐specific Salmonella prevalence in different human populations and identified the most common serotypes. Published literature of Salmonella prevalence was systematically reviewed and reported following the Preferred Items for Systematic Reviews and Meta‐Analysis (PRISMA) guidelines. Pooled Salmonella prevalence measures were estimated using a random‐effects model. We identified 46 research reports that reported 84 Salmonella prevalence measures in 15 out of 24 countries in MENA. There were 252,831 tested humans with 6,356 Salmonella‐positive cases. The pooled Salmonella prevalence in MENA was estimated at 6.6% (95% confidence interval (CI): 5.4%–7.9%). The highest pooled Salmonella prevalence measures were in Morocco (17.9%, 95% CI: 5.7%–34.8%, 1997–2012), Tunisia (10.2%, 95% CI: 4.3%–18.0%, 1988–2009) and Sudan (9.2%, 95% CI: 6.5%–12.2%, 2006–2008), while the lowest were in Jordan (1.1%, 95% CI: 0.1%–3.0%, 1993–2010), Oman (1.2%, 95% CI: 1.2%–1.3%, 1998–2002) and Palestine (1.2%, 95% CI: 0.4%–2.1%, 1999–2011). In MENA, Salmonella pooled prevalence in gastrointestinal symptomatic, gastrointestinal asymptomatic and food handlers population groups was 13.0% (95% CI: 7.6%–19.6%), 11.4% (95% CI: 2.2%–25.7%) and 3.8% (95% CI: 1.0%–8.0%), respectively. Salmonella prevalence was 14.5% (95% CI: 8.7%–26.1%) in studies tested <100 subjects, whereas 4.6% (95% CI: 3.6%–5.8%) in studies tested ≥100 subjects. Salmonella Enteritidis (29.8%) and Typhimurium (23.6%) were the most common serotypes. Salmonella was a common foodborne pathogen in MENA countries, particularly in North African countries. Findings inform the scientific community, the public and the decision‐makers with Salmonella prevalence and gaps in evidence in MENA to support control and prevention strategies and could leverage more research studies.     

Bacterial Culturing of Ventral Median Celiotomies for Prediction of Postoperative Incisional Complications in Horses

Objective - The purpose of this study was to determine whether detection of bacterial contamination of ventral midline incisions was predictive of postoperative incisional complications in horses undergoing exploratory celiotomy for colic. Study Design - Prospective study. Animal or Sample Population - Horses that had ventral median celiotomies for colic at Colorado State University between May 1, 1991 and April 30, 1993 were studied prospectively. Complete information was obtained on 66 horses. Methods - Bacterial cultures were obtained from ventral midline incisions at surgery. Information regarding the type of surgery performed (celiotomy vs celiotomy plus enterotomy or enterectomy), preoperative total nucleated cells and presence of a left shift, postoperative fever (>38.5°C), incisional drainage, incisional herniation, and outcome were obtained from medical records. Additional information concerning incisional drainage, herniation, and survival was obtained at a minimum of 18 months after surgery. Results - Examination of odds ratio (ORs) and confidence intervals (CIs) revealed that a celiotomy plus enterotomy or enterectomy was positively, but not significantly, associated (OR > 1) with positive culture results, presence of incisional drainage and incisional herniation. A significant association between incisional drainage and hernia formation was found; odds of incisional herniation were 62.5 times greater in horses that had incisional drainage. Incisional drainage and herniation were negatively associated with patient survival. The later association was significant (OR = 0.18, P=.04). Conclusions - This study indicated that detection of bacterial contamination at incisional closure by the swab culture technique was not beneficial in the prediction of postoperative incisional problems in horses undergoing colic surgery. Incisional drainage or infection appeared to be associated with hernia formation. Clinical Relevance - Immediate treatment of incisional drainage or methods to prevent incisional infections may decrease hernia formation.     

Short-term survival and mortality rates in a retrospective study of colic in 1588 Danish horses

Background

Outcomes of colic treatment are of great interest to clinicians, horse owners and insurers. One commonly used criterion of success is the overall short-term survival rate. This is used as to compare treatments and to measure quality of veterinary care, but may be biased by demographic or social factors such as attitudes towards animal suffering and euthanasia. The aims of this study were to 1) describe and analyse characteristics in horses with signs of colic referred to the University Hospital for Large Animals (UHLA), University of Copenhagen, Denmark over a 10-year period and 2) to compare these rates with those published in other comparable studies.

Results

The overall survival rate for colic horses over the 10-year study period was 68% (confidence intervals (CI): 66–71%; 1087/1588). In the medical group, 1093 horses, short-term survival was 87% (CI: 85–89%). Thirty one % of referred horses were given diagnoses requiring surgical intervention (CI: 29–33%). In this group 32% of the horses were euthanized before surgery (CI: 28–36%; 159/495). Of the surgical cases 27% (CI: 23-31%) were euthanized or died during surgery. Of the horses that recovered from surgery 25% died or were euthanized (CI: 19–32%; 48/189), while 75% survived to discharge (CI: 68–81%).

Conclusions

The short term survival rates of Danish horses with colic were similar or lower to those reported from other countries. Apart from variability of veterinary care, attitudes towards euthanasia vary among the countries, which may bias the outcomes. This study indicates that qualitative interview studies on owners’ attitudes towards animal suffering and euthanasia need to be conducted. Our opinion is that survival rates are not valid as sole indicators of quality of care in colic treatment due to selection bias. If the survival rates are to be compared between hospitals, techniques or surgeons, prospective studies including mutually agreed-on disease severity scores and a predefined set of reasons for euthanasia are needed.