Carriage and acquisition rates of Clostridium difficile in hospitalized horses, including molecular characterization, multilocus sequence typing and antimicrobial susceptibility of bacterial isolates.

Clostridium difficile has been identified as a significant agent of diarrhoea and enterocolitis in both foals and adult horses. Hospitalization, antibiotic therapy or changes in diet may contribute to the development of C. difficile infection. Horses admitted to a care unit are therefore at greater risk of being colonized. The aim of this study was to investigate the carriage of C. difficile in hospitalized horses and the possible influence of some risk factors in colonization. During a seven-month period, faecal samples and data relating the clinical history of horses admitted to a veterinary teaching hospital were collected. C. difficile isolates were characterized through toxin profiles, cytotoxicity activity, PCR-ribotyping, antimicrobial resistance and multilocus sequence typing (MLST). Ten isolates were obtained with a total of seven different PCR-ribotypes, including PCR-ribotype 014. Five of them were identified as toxinogenic. A high resistance to gentamicin, clindamycin and ceftiofur was found. MLST revealed four different sequencing types (ST), which included ST11, ST26, ST2 and ST15, and phylogenetic analysis showed that most of the isolates clustered in the same lineage. Clinical history suggests that horses frequently harbour toxigenic and non-toxigenic C. difficile and that in most cases they are colonized regardless of the reason for hospitalization; the development of diarrhoea is more unusual.

Prevalence and risk factors for cardiac diseases in a hospital-based population of 3,434 horses (1994-2011).

BACKGROUND: Risk factors for cardiac diseases in horses have not been explored in a large population of animals. OBJECTIVES: To describe risk factors for various cardiac diseases in a hospital-based population of horses. ANIMALS: Files of 3,434 horses admitted at the Internal Medicine Department of the Liege Equine Teaching Hospital between 1994 and 2011 were reviewed and of those, 284 were categorized as having moderate-to-severe cardiac disease. METHODS: Observational study. After calculating prevalence for each cardiac disease, we tested whether breed (chi-square test) or sex, age, body weight (BW), and other cardiac diseases (logistic regressions) were risk factors (p < .05 significant). RESULTS: Mitral regurgitation (MR, 4.4%), atrial fibrillation (AF, 2.3%), aortic regurgitation (AR, 2.1%), and tricuspid regurgitation (TR, 1.7%) were the most common cardiac abnormalities detected. Determinants were male sex and increasing age for AR (OR = 2.03, CI = 1.07-4.94), racehorses breed and middle-age for TR (OR = 4.36; CI = 1.10-17.24), and high BW for AF (OR = 3.54; CI = 1.67-7.49). MR was the most common valvular disease associated with AF, clinically important ventricular arrhythmia, pulmonary regurgitation (PR), and congestive heart failure (CHF). TR was also associated with AF, PR, and CHF; AR was not associated with CHF. CONCLUSIONS AND CLINICAL IMPORTANCE: Several previously suspected risk factors for a variety of equine cardiac diseases are statistically confirmed and other risk factors are highlighted in the studied hospital-based population. These observations should be taken into account in health and sport's monitoring of horses presenting predisposing factors.

Effect of breed, sex, age and body weight on echocardiographic measurements in the equine species.

Little is known about the effect of various animal's signalment variables on echocardiographic reference values in the equine species. This study was performed to evaluate the effect of sex, breed, age and body weight (BW) on echocardiographic measurements in the equine species. Echocardiography was performed on 212 ponies or horses of various breeds, aged from 1 day to 37 years old (mean±SD: 7.8 ± 5.8 years), BW 38-890 kg (mean ± SD: 421 ± 133 kg), and free of cardiac disease. Fifty of those animals aged from 2 months to 35 years old (mean ± SD: 11.6 ± 6.4 years old); BW 77-662 kg (mean ± SD: 436 ± 135 kg) were also examined using the pulsed-wave Doppler mode. Standard two-dimensional and M-mode echocardiography were performed on all animals. Standard pulsed-wave Doppler examination of each cardiac valve was performed on the 50 first examined animals. Data were analysed using a general linear model including the effect of sex, age, breed and BW after logarithmic transformation of the data. Therefore, the same analysis was performed separately on animals aged ≤ 2 years-old and on older animals. All dimensional echocardiographic measurements were significantly affected by BW and most of them were significantly affected by breed, but not by sex. Only the aortic and the pulmonary artery internal diameter were significantly affected by age. None of the Doppler measurements were significantly affected by the tested variables. In conclusion, in the equine species, dimensional echocardiographic reference values should be established using regression equations as a function of BW, which could increase the diagnostic value of this leading technique in equine cardiology. Breed could also have an effect on those measurements.

Two-dimensional and M-mode echocardiographic reference values in healthy adult Saanen goats.

Echocardiography has become a routine non-invasive cardiac diagnostic tool in most species. Accurate measurement of cardiac dimensions requires reference values, which are poorly documented in goats. The aim of the present study was to test the inter-day repeatability and to establish the reference values of two-dimensional (2D-) and time-motion (M-) mode echocardiographic variables in healthy adult Saanen goats. Six goats were investigated three times by the same observer at one-day interval using a standardised 2D- and M-mode echocardiographic protocol. The intra-observer inter-day repeatability was tested using analysis of variance, calculation of the coefficient of variation and confidence intervals. A single echocardiographic examination was performed in six other goats, and values obtained in the 12 goats were used to establish the 2D- and M-mode echocardiographic reference values in healthy adult female Saanen goats. Statistical analysis revealed a good inter-day repeatability of the echocardiographic cardiac measurements. Echocardiographic reference values obtained in healthy adult Saanen goats seemed slightly higher than those reported in healthy Swedish domestic goats and were similar to those reported in healthy adult sheep.

Dynamic 320-section CT angiography in cranial arteriovenous shunting lesions.

Novel 320-section CT scanning equipment enables dynamic noninvasive angiographic imaging of the entire cranial vasculature (4D-CTA). We describe this technique and demonstrate its potential in arteriovenous shunting lesions. 4D-CTA imaging resulted in a correct diagnosis, lesion classification, and treatment-strategy selection in 3 patients, compared with CA. We think that 4D-CTA can further reduce the need for CA, sparing the patient the discomfort and risk associated with an invasive procedure.