Equine scintigraphy has been legally permitted in Japan since 2009; however, it has not yet been a routine modality for horses. One reason is the legal regulations concerning the disposal of contaminated bedding. However, overseas, the bedding after scintigraphy can be disposed following radioactivity decay, but this is not allowed in Japan. Therefore, beddings are required to stored permanently in a controlled area, implying that large amounts of beddings such as straw would be kept untreated, which is quite unpractical. This may cause a hospital owner to hesitate to construct an equine scintigraphy facility. Therefore, it is proposed that water-dispersed paper bedding is disposed as aqueous waste after radioactivity decay. The purpose of this study was to check the availability of bedding, thus radioisotopes were not used in this study. Three horses were housed individually in stalls covered with water-dispersed paper bedding for 48 hr. Physical condition, including body weight, was monitored, and a complete blood cell count and biochemical analysis were conducted. The results revealed that physical conditions and results of blood analysis were all stable within the normal range, and the veterinarian did not find any specific abnormality in any of the three horses. No marked changes in the levels of blood cortisol were observed before and after stalling, suggesting almost no stress for the horses. Because the water-dispersed paper bedding did not negatively affect the horses, it can be used as a substitute for conventional straw bedding.
Keywords: Technetium 99m (99mTc); bedding; physical half-life; scintigraphy; water-dispersed paper.