The changing pattern of “doping” in horse racing and its control

Extract

Horse racing is a fine old sport and often, in England at least, has been referred to as the Sport of Kings. Yet, in spite of its antiquity and its favour in high places, it has often been plagued by numerous forms of corrupt practices. Perhaps one of the commonest forms of malpractice has been the illicit administration of drugs to racehorses for the purpose of helping them to win or causing them to lose. Such practice is popularly known as “doping” or “drugging”.     

The Friesian horse breed: A clinical challenge to the equine veterinarian?

The Friesian horse breed is a beautiful breed for showing, riding and driving. However, some clinical problems seem to have a higher incidence in the Friesian breed compared to other breeds and this raises suspicions that these clinical entities may have a genetic basis.     

Problems at the human–horse interface and prospects for smart textile solutions

The significant potential for so-called “smart textiles” in the design of the next generation of devices that measure pressure, tension, moisture, and heat at the human–horse interface is discussed in this article. Research techniques from theoretical and experimental physics laboratories, combined with wireless technology, can be readily adapted to measure and store metrics for numerous variables in equine structure and function. Activities, such as breathing, the extension and flexion of joints, limb kinematics, and cardiac function, can be logged as indicators of physiological and behavioral conditioning (training). Such metrics may also, one day, support veterinary diagnostics but also play a role in safeguarding sport-horse welfare, especially in elite contexts where the horse may be pushed to its functional limits. As such, they are likely to emerge as an area of great interest to equitation and welfare scientists. It is important to note that smart textiles sense and react to exogenous stimuli via integrated sensors. So, beyond the equitation science laboratory, the emergence of polymers and smart materials may enhance the effectiveness of, or challenge us to completely rethink, traditional items of saddlery, thus improving equitation. The integration of smart textiles in all sorts of extant and emergent equipment for everyday equestrians could, in the future, lead to equipment that responds appropriately to the demands of equitation in its various forms. Rethinking equitation through physics and the use of smart textiles seems to have merit in that it is a novel means of both investigating and addressing problems that compromise the welfare and performance of horses. The purpose of this article is to envision the use of smart textiles in research, clinical, equestrian, and horse care contexts.     

Early pregnancy in the horse revisited–does exception prove the rule?

Early equine pregnancy shares many features with that of more intensively assessed domestic animals species, but there are also characteristic differences. Some of those are poorly understood. Descent of the equine conceptus into the uterine lumen occurs at day 5 to 6 after ovulation but is only possible when the embryo secretes prostaglandin E2. Although maintenance of equine pregnancy probably involves secretion of a conceptus derived anti-luteolytic factor, this agent has not been identified. Rapid growth, conceptus mobility and presence of an acellular capsule at the time of maternal recognition of pregnancy, i.e. between days 12 and 14, are prerequisites to avoid pregnancy loss. Progesterone together with 5α-pregnanes is secreted by the corpus luteum and induces the production of endometrial histotroph which is responsible for conceptus nutrition until placention. A stable contact between the outer trophoblast layer of the allantochorion and the luminal epithelium of the endometrium is not established before days 40 to 42 of pregnancy.     

Historical aspects of Potomac horse fever in Ontario (1924–2010)

In the summer of 1924 Dr. Frank W. Schofield conducted investigations into an endemic disease of horses in the Kent and Essex counties of Ontario. According to farmers in these counties the disease had existed in this region for at least 50 years previously. The clinical, pathological, histopathological, and epidemiological findings outlined in Schofield’s detailed report strongly suggest that this endemic disease was what was designated in 1979 as “Potomac horse fever” (PHF). This assumption is further substantiated by transmission experiments involving horses and laboratory animals that were conducted by Schofield utilizing horse feces, whole blood, and mayflies. The aim of this paper is to present Schofield’s detailed investigations and findings and to compare these with PHF research conducted from 1979 to 2010 that ultimately led to the discovery of Neorickettsia risticii as the etiological agent and to elucidation of the organism’s complex life cycle.     

Gastric squamous cell carcinoma in the horse: Seven cases (2009–2019)

This report describes gastric squamous cell carcinoma (GSCC) in seven horses. It records the clinical signs, treatment and outcomes. Main clinical signs were mostly nonspecific and included weight loss, anorexia, fever, tachycardia and tachypnoea. Some more suggestive clinical signs were observed such as recurrent choke, halitosis and hypersalivation. Chronic anaemia and hypoalbuminaemia were common findings. Gastroscopy identified a gastric mass in four cases (57.1%); however, visualisation of the stomach was precluded in the other three horses due to distal oesophageal neoplastic infiltration and compression. Gastric wall thickening was noticed using abdominal ultrasonography in four horses (57.1%). Neoplastic cells could only be detected in the peritoneal fluid of 2 out of 7 horses. Endoscopic-guided or transabdominal ultrasound-guided biopsies allowed an ante-mortem diagnosis in three horses (42.8%). Gastric masses were identified at post-mortem examination and metastasis were confirmed in the liver and/or the spleen for 4/4 cases. In the cases for which palliative therapy was attempted, most of the horses were subjected to euthanasia within 4 weeks. In conclusion, GSCC is an uncommon neoplastic disease in horses. A combination of diagnostic tests is often necessary to achieve a diagnosis, which is frequently only made late in the course of the disease. As a result, GSCC is commonly associated with a poor short-term prognosis.     

The proximal aspect of the suspensory ligament in the horse: How precise are ultrasonographic measurements?

Reasons for performing study: To evaluate intra‐ and interobserver variability in ultrasonographic measurements of the proximal aspect of the suspensory ligament (PSL) in the horse. Hypothesis: A minimum difference of ≥20% is required to differentiate reliably between physiological and pathological alterations related to dimensions. Materials and methods: Two operators examined the PSL in all 4 limbs of 14 horses twice using different techniques and different probes with and without standoff pads. Measurements were taken from the longitudinal and transverse images. Inter‐ and intraoperator variability was evaluated using agreement indices (AI) and the 95% limits of agreement (LOA). Results: On the longitudinal scan the mean inter‐ and intraoperator AIs for dorsopalmar/‐plantar thickness were both ≥0.89 and the 95% LOA were within target values for almost all intra‐ and interoperator comparisons. Similar mean AIs and 95% LOA were calculated for the dorsopalmar/‐plantar thickness on the transverse image. For lateromedial width, cross‐sectional area and circumference on the transverse scan, the mean inter‐ and intraoperator AIs ranged between 0.81 and 0.95 and the 95% LOA were higher than target values regardless of the imaging technique used. In general, better values for AIs and 95% LOA were achieved in the fore‐ compared with the hindlimb. Conclusion and clinical relevance: Acceptable precision was identified within and between operators only for the dorsopalmar/‐plantar thickness in longitudinal and in transverse scanning directions. For the lateromedial width, cross‐sectional area and circumference, a relatively large variability was identified. This aspect has to be considered if these parameters are to be used for objective measurement of the PSL from the transverse ultrasound image.     

Virus–host interaction in feline immunodeficiency virus (FIV) infection

Feline immunodeficiency virus (FIV) infection has been the focus of several studies because this virus exhibits genetic and pathogenic characteristics that are similar to those of the human immunodeficiency virus (HIV). FIV causes acquired immunodeficiency syndrome (AIDS) in cats, nevertheless, a large fraction of infected cats remain asymptomatic throughout life despite of persistent chronic infection. This slow disease progression may be due to the presence of factors that are involved in the natural resistance to infection and the immune response that is mounted by the animals, as well as due to the adaptation of the virus to the host. Therefore, the study of virus–host interaction is essential to the understanding of the different patterns of disease course and the virus persistence in the host, and to help with the development of effective vaccines and perhaps the cure of FIV and HIV infections.     

Congenital Pelger-Huët anomaly in a horse

Abstract A 1.5‐year‐old male Arabian horse was referred to the Louisiana State University Veterinary Teaching Hospital and Clinic for an open deep laceration involving two thirds of the right trunk. The initial CBC results included an inflammatory leukogram, characterized by a marked degenerative left shift consisting of only immature band neutrophils (7500/μL, reference interval 0–100/μL) with toxic changes and no segmented neutrophils (0/μL, reference interval 2700–6700/μL). On abdominal ultrasonography, free abdominal fluid was found and collected for analysis. Abdominal fluid had a marked increase in total nucleated cells (40,600 cells/μL) consisting of 74% nondegenerate neutrophils that all were hyposegmented, with mature condensed chromatin. Re‐evaluation of neutrophil morphology on the initial blood smear confirmed hyposegmentation and mature condensed chromatin, similar to that observed in cells in the abdominal fluid. A diagnosis of Pelger‐Huët anomaly (PHA) was made in this colt. Congenital PHA was documented on the basis of persistent neutrophil hyposegmentation on serial blood smears, ruling out of acquired causes of PHA, and findings of similar neutrophil hyposegmentation on blood smears from the colt's sire and the sire's siblings. To our knowledge, this is the first reported case of congenital PHA in a horse.     

Pelger-Huët anomaly in an Arabian horse

Abstract Abstract: A 9‐year‐old Arabian mare was evaluated for a 7‐day history of malaise. Results of a CBC included a leukocyte concentration within the reference interval (8.4 × 10³/μL, reference interval 6.0–14.0 × 10³/μL) with an apparent degenerative left shift (segmented neutrophils 1.2 × 10³/μL, reference interval 2.5–7.5 × 10³/μL; hyposegmented neutrophils 1.8 × 10³/μL, reference interval 0.0–0.2 × 10³/μL). Serum clinical chemistry results included increased aspartate transaminase, alkaline phosphatase, and gamma‐glutamyltransferase activities. A presumptive diagnosis of hepatitis or cholangiohepatitis was made. The horse was treated with antimicrobials and the malaise quickly resolved. However, in a recheck CBC on day 13, the apparent degenerative left shift remained. Further evaluation of the blood smear revealed many hyposegmented granulocytes with coarse mature chromatin and normal cytoplasmic features. On the basis of the microscopic examination, the horse was diagnosed with Pelger‐Huët anomaly. The patient's offspring was subsequently also diagnosed with Pelger‐Huët anomaly on the basis of blood film examination. Neutrophil, eosinophil, and basophil mean nuclear scores in both affected horses (mare, range 1.5–2.6; offspring, range 1.6–3.2) were lower than those in 2 unrelated Arabian horses (range, 2.8–5.0) and 5 non‐Arabian control horses (range, 2.8–5.0). Results of immunophenotyping and phagocytosis/oxidative burst assays via flow cytometry showed no difference in the expression of myeloid–specific or adhesion molecules or in neutrophil function between affected and control horses. This is the second known report of equine Pelger‐Huët anomaly, both of which affected Arabian horses.     

Antimicrobial associated diarrhoea in the horse. Part 2: Which antimicrobials are associated with AAD in the horse?

Almost all oral and parenterally administered antimicrobials have been linked with antimicrobial associated diarrhoea (AAD) in both man and horses, although some antimicrobials clearly pose a higher risk.