The physiological effect on the equine respiratory tract of recycled phone book paper vs. sawdust bedding was investigated in 12 mares with no clinical signs of respiratory disease. Mares were housed in a 20-stall barn and randomly assigned to one of two treatment groups (Group 1=sawdust; Group 2=phone book paper) for 14 days. After a 14-day turnout, Group 1 was assigned to phone book paper and Group 2 was assigned to sawdust for 14 days using a crossover experimental design. Endoscopic examinations of the upper respiratory tract and trachea along with tracheal washes (TW) were performed on days 0 and 14 of each trial. Cytologic examinations were performed on TW samples. Cell type and laboratory interpretation of TW samples were noted. There was no difference (P>0.05) in cell type between treatment groups within or across trials. Laboratory interpretation indicated no abnormalities in 30 of 48 TW samples. Stall conditions were visually rated and graded daily for drinking water cleanliness, depth of bedding and absorbency, overall cleanliness, ammonia odor, and aerial ammonia levels. The phone book paper bedding was more absorbent (P<0.01), had a cleaner appearance (P<0.01), and had lower aerial ammonia levels (P<0.01) than the sawdust bedding. The phone book paper was effective in controlling aerial ammonia and did not adversely affect the respiratory health of clinically normal horses based on the diagnostic tests performed in this study. Phone book paper did effect the outward appearance of the horses, as horses housed on phone book paper had a dustier outward appearance. In addition, pigment was seen in the TW samples of 12 horses bedded on phone book paper, whereas it was rarely noted in horses bedded on sawdust. Overall, phone book paper appeared to be a viable option for horse bedding when compared to sawdust.
All Science Journal Classification (ASJC) codes