ABSTRACT
In this study, we examined the effects of pre-cooling on thermophysiological responses in horses exercising in moderate environmental conditions (average wet bulb globe temperature: 18.5 ± 3.8 °C). Ten international eventing horses performed moderate intensity canter training on two separate days, and were either pre-cooled with cold-water rinsing (5-9 °C for 8 ± 3 min; cooling) or were not pre-cooled (control). We determined velocity (V), heart rate (HR), rectal temperature (Tre,), shoulder and rump skin temperature (Tshoulder and Trump), plasma lactate concentration (LA), gross sweat loss (GSL), and local sweat rate (LSR), as well as sweat sodium, chloride and potassium concentrations. The effect of pre-cooling on Tre was dependent on time; after 20 min of exercise the effect was the largest (estimate: 0.990, 95% likelihood confidence intervals (95% CI): 0.987, 0.993) compared to the control condition, resulting in a lower median Tre of 0.3 °C. Skin temperature was also affected by pre-cooling compared to the control condition (Tshoulder: -3.30 °C, 95% CI: -3.739, -2.867; Trump: -2.31 °C, 95% CI: -2.661, -1.967). V, HR, LA, GSL, LSR and sweat composition were not affected by pre-cooling. In conclusion, pre-cooling by cold-water rinsing could increase the margin for heat storage, allowing a longer exercise time before a critical Tre is reached and, therefore, could potentially improve equine welfare during competition.
ABSTRACT
In tropical and subtropical climates, infection of periocular tissue by Habronema larvae is a recognised cause of conjunctivitis or blepharitis. To the authors' knowledge, only a few cases of habronemiasis have been described in Western Europe, and it has not been documented previously in the Netherlands. The objective of this report is to describe the occurrence of five cases of (peri)ocular habronemiasis in the Netherlands, of which four date from the past few years. The diagnosis was based on the history, clinical signs and histopathologic examination of biopsy specimens. A granulomatous conjunctivitis/dermatitis and sulphur-like granules were present in all cases. Histopathology showed an eosinophilic granulomatous inflammation, and three out of five (60 per cent) samples revealed one or more nematodes on section. Treatment combinations with surgical excision, local corticosteroid and/or anthelmintic drugs were used. Furthermore, all horses received ivermectin or moxidectin. Treatment resulted in healing of the lesions in four horses. One case, which was refractory to treatment, resolved spontaneously after the onset of colder weather. This case series suggests an increased prevalence of (peri)ocular habronemiasis in the Netherlands. This diagnosis should therefore be considered when being presented with a horse with granulomatous conjunctivitis/dermatitis in Western Europe, especially during the summer months.