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K Verheyen

Publications and source records attributed to K Verheyen.

9 recordsLinked to original sources
PubMed2006

The effect of conformation on orthopaedic health and performance in a cohort of National Hunt racehorses: preliminary results.

REASONS FOR PERFORMING STUDY: There is a lack of scientific data and studies on the effect of conformation on performance or on orthopaedic health. OBJECTIVES: To investigate the relationship between conformation, injury and performance in racehorses used for racing over fences. METHODS: Over 2 years, 108 National Hunt racehorses were followed and their medical and performance data recorded. Conformation was measured in 3D with a computerised motion analysis system. Linear multiple regression models were used to evaluate the effect of conformation on measures of race performance and stepwise forward logistic regression models to assess the effect on risk of injury. RESULTS: An increase in intermandibular width, flexor angle of the shoulder joint and coxal angle (the angle between the ilium and ischium) was demonstrated to have a positive effect on performance. Performance decreased with increasing girth, length of the hind digit and valgus conformation of the metacarpophalangeal joint. The risk of suffering from superficial digital flexor tendon injury increased with increasing metacarpophalangeal joint angle and with carpus valgus conformation. The risk of pelvic fracture increased with valgus conformation of the tarsus and decreased with an increasing coxal angle. CONCLUSION: Valgus deformation was demonstrated to be detrimental to performance or increased risk of injury, perhaps resulting in higher loads on musculoskeletal structures. The coxal angle was the only parameter to have an effect on both risk of injury and performance. An alignment of the muscles with the axis of the pelvis may be beneficial for force transmission and decrease the bending moment of the muscles on the bones. The statistical power of this study is limited, however it provides preliminary data necessary for the planning of a larger scale study on the effect of conformation on performance and risk of injury. CLINICAL RELEVANCE: Studies of the effects of conformation on performance and risk of injury may aid in identifying individuals likely to perform well on the racecourse and avoid risks of injury.

Animals↗
PubMed2003

Gender differences in bone turnover in 2-year-old Thoroughbreds.

REASONS FOR PERFORMING STUDY: Injuries to the skeleton are a major cause of morbidity and mortality in racehorses and age, gender and season have all been shown to influence risk of injury. OBJECTIVES: To use biochemical markers of bone cell activity to establish to whether cellular processes in bone underlie these described effects. METHODS: Blood samples were collected monthly from 2-year-old horses in race training between November 1998 and September 1999. Mean age at the start of the study was 20 months (range 18-23 months), with no significant difference in average age between colts (n = 84) and fillies (n = 63). Three markers were measured; osteocalcin (OC, bone formation), the carboxyterminal cross-linked telopeptide of type I collagen (ICTP, bone resorption) and the carboxyterminal propeptide of type I collagen (PICP), which is less 'bone-specific' than the other 2 markers. RESULTS: Colts had, on average, 3.62 ng/ml higher OC concentrations (P = 0.044) and 0.68 mg/l higher ICTP concentrations (P = 0.01) than fillies. The effect of gender was not statistically significant for PICP. However, in May, PICP concentrations were on average 157 mg/l higher in fillies than colts. There was no effect of age or season on marker concentrations. CONCLUSIONS: This study has shown that there are gender differences in bone turnover markers in 2-year-old Thoroughbreds; however, age, within the limited range studied, did not have a significant effect on bone cell activity. Lower bone marker concentrations may reflect smaller bone size and/or earlier skeletal maturation in fillies. An increase in concentrations of PICP in fillies in spring and early summer may relect an influence of sex hormones on collagen turnover. POTENTIAL RELEVANCE: Gender differences in bone cell activity in 2-year-old colts and fillies may influence bone's adaptive responses to training and risk of injury.

Age Factors↗
PubMed2000

Elimination of guttural pouch infection and inflammation in asymptomatic carriers of Streptococcus equi.

Three protracted outbreaks of strangles were investigated using endoscopic examination and a total of 14 asymptomatic carriers of Streptococcus equi were identified of which 13 showed evidence of carriage in the guttural pouch. Treatment was initiated to eliminate S. equi colonisation since these animals posed an infectious risk to susceptible horses. Two further horses were referred to us with severe guttural pouch pathology and from which S. equi was cultured, and treatment of these cases is also described. Treatment in the first instance was directed towards removal of gross guttural pouch pathology as seen on endoscopic examination. This was done with a combination of irrigation of the pouch with moderate to large amounts of saline, suction of fluid material and endoscopic manipulation of chondroids. Subsequently, antibiotic treatment was used to eliminate S. equi infection. All animals received systemic antibiotics, in some cases combined with topical antimicrobial treatment. Treatment was generally regarded as successful when the guttural pouches appeared normal and S. equi was not detected in nasopharangeal swabs and pouch lavages on 3 consecutive occasions. Successful treatment of one carrier required surgical intervention due to occlusion of both guttural pouch pharyngeal openings. Fourteen of 15 carriers were successfully treated by endoscopic removal of inflammatory material and antibiotic treatment, without surgical intervention. Five carriers originally given potentiated sulphonamide (33%) required further therapy with penicillin or ceftiofur, administered both systemically and topically, before S. equi infection and associated inflammation of the guttural pouches were eliminated.

Animals↗
PubMed2000

Control of strangles outbreaks by isolation of guttural pouch carriers identified using PCR and culture of Streptococcus equi.

Previous use of repeated nasopharyngeal swabbing and culture of Streptococcus equi showed that healthy carriers developed in more than 50% of 'strangles' outbreaks. The guttural pouches were the only detectable site of S. equi colonisation on endoscopic examination of horses during one of these outbreaks and S. equi was sometimes not detected by culture of nasopharyngeal swabs from carriers for up to 2 or 3 months before nasal shedding resumed sporadically. A more sensitive way of detecting S. equi on swabs from established guttural pouch carriers was therefore required. Conveniently selected 'strangles' outbreaks were investigated in detail using endoscopy, in order to develop and assess a suitable polymerase chain reaction (PCR) test. We report here 3 protracted 'strangles' outbreaks on different kinds of establishments in which between 29 and 52% of sampled horses were infected as detected by culture and/or PCR. Of the infected horses, between 9 and 44% were identified as carrying S. equi after clinical signs had disappeared and the predominant site of carriage was the guttural pouch. Prolonged carriage of S. equi, which lasted up to 8 months, did not cease spontaneously before treatment was initiated to eliminate the infections. The detection and isolation of the carriers, in conjunction with strict hygiene measures, apparently resulted in the control of the outbreaks and allowed the premises to return to normal activity. Comparing PCR and culture, many more swabs were found to be positive using PCR (56 vs. 30% of 61 swabs). Similar results were obtained for guttural pouch samples from 12 established carriers (PCR 76% and culture 59%). These results from repeated samples from relatively few animals need confirming using more long-term carriers. PCR can also detect dead organisms and is, therefore, liable to yield false positive results. Despite this drawback, it is argued that PCR provides a potentially useful adjunct to culture of nasopharyngeal swabs in the detection of asymptomatic carriers of S. equi following outbreaks of 'strangles'.

Animals↗
PubMed1999

Equine influenza in the United Kingdom in 1998.

In 1998, equine influenza was diagnosed by serology and nucleoprotein enzyme-linked immunosorbent assay as the cause of acute respiratory disease in vaccinated and unvaccinated horses in the UK. The signs were generally milder in vaccinated horses and completely susceptible animals showed the most severe signs, including pyrexia, inappetence, coughing, mucopurulent nasal discharge and secondary bacterial pneumonia. In a detailed investigation of an outbreak among 52 vaccinated thoroughbreds in a flat racing yard, more than 60 per cent of the horses seroconverted on the evidence of paired serum samples tested by single radial haemolysis (SRH). Preliminary sequencing and characterisation of an isolate from this outbreak indicated that it was an 'American-like' strain. In addition, in this outbreak there was a larger proportion of horses with preinfection SRH titres greater than 140 mm2 that subsequently seroconverted than in other recent outbreaks from which 'European-like' strains have been isolated. This result suggested that the cross-protectivity between circulating 'American-like' strains and the 'European-like' strains of A/equine-2 viruses present in current vaccines may be decreasing.

Animals↗
PubMed1983

In vitro expression of alpha-L-fucosidase activity polymorphism observed in plasma.

Several quantitative and qualitative characteristics of alpha-L-fucosidase were studied in cultured skin fibroblasts derived from variant and non-variant individuals. In comparison with non-variant cultures with similar growth characteristics, the intracellular level of alpha-L-fucosidase was specifically reduced by at least 50% at all stages of the culture cycle. The amount of enzyme released into the growth medium was also decreased, but the ratio of the extracellular enzyme to the total enzyme activity produced, was not significantly different from that in non-variant cultures. pH-dependence, apparent Km value and temperature sensitivity of the variant alpha-L-fucosidase were identical to that of the enzyme in non-variant cells. Specific differences between the variant and non-variant enzyme were consistently observed upon enzyme inactivation at acid pH and in thermostabilisation studies with NaCl. The DEAE elution profiles and pH-dependent association patterns obtained by ultracentrifugation were also different for both types of intracellular alpha-L-fucosidase. It is concluded that the quantitative as well as the qualitative differences of alpha-L-fucosidase characteristics found in variant fibroblasts are the in vitro expression of the variant genotype, already phenotypically observed in human plasma.

Cells, Cultured↗