Glucocorticoid assessment in the domestic horse: The impacts of time and climatic variables on sample integrity.

BACKGROUND: Assessment of faecal glucocorticoid metabolites (FGM) offers a noninvasive method of monitoring adrenal activity in domestic horses. Samples are collected on an opportunistic basis and, if they are not fresh or have been exposed to the elements before they are identified, may not accurately reflect FGM concentrations. OBJECTIVES: To explore the impact of a range of environmental conditions upon the integrity of FGM levels in equine faeces. STUDY DESIGN: In vitro experiment. METHOD: Equine faeces were exposed to six controlled environmental conditions intended to simulate a range of weather and seasonal patterns (temperate climate, high heat, high heat and rainfall, temperate climate and rainfall, high heat/temperate climate, freeze/thaw) over a period of 5 days. FGM were quantified using an enzyme-linked immunoassay. RESULTS: Faecal samples exposed to room temperature and high heat demonstrated significant increases in FGM levels over time. No changes in FGM levels were observed in the remaining treatments. MAIN LIMITATIONS: The study should be repeated in field conditions and with known high and low levels of FGM to further inform sampling regimes. CONCLUSIONS: Adrenal monitoring in the domestic horse should be performed with consideration of the impact of climate on the integrity of faecal samples in order to further inform sampling schedules and improve the reliability of results.

Reducing exposure to pathogens in the horse: a preliminary study into the survival of bacteria on a range of equine bedding types.

AIMS: To compare the rate of growth of four microbial strains that cause disease in the horse, on four commonly used types of bedding. The moisture-holding capacity of each bedding type was also tested. METHODS AND RESULTS: Microbial strains included Streptococcus equi, Streptococcus zooepidemicus, Fusobacterium necrophorum, Dichelobacter nodosus and Dermatophilus congolensis. The bedding types tested were Pinus sylvestris (Scots pine shavings), Pinus nigra (Corsican pine shavings), Picea sitchensis (Sitka spruce shavings), Cannabis sativa (hemp) and chopped wheat straw. A suspension of each microbial strain was spread in triplicate on agar media and incubated in its optimal growth conditions. The viable count (colony-forming unit per ml) was determined for each bacterial strain for the five different bedding types. Pinus sylvestris bedding resulted in significantly less (P = 0·001) bacterial growth of all strains tested. CONCLUSIONS: Factors resulting in the inhibition of bacterial growth include the antibacterial effects reported in the Pinacea family and the physical properties of the bedding substrate. Research is currently focussed on the diagnosis and management of disease. Prevention of disease is also important for matters of biosecurity. Strategies should include the provision of a hygienic environment and the use of specific types of bedding. SIGNIFICANCE AND IMPACT OF THE STUDY: Bedding choice has implications for global equine health and disease prevention as well as potential benefits in other animal species.