Abstract
Thoroughly dampened feed was treated with Sudan III dye in acetone. The dyed feed was dried and fed as part of the daily ration to sheep, and feces collected hourly for 60 hr. in an apparatus designed to change feces collection receptacles at hourly intervals. A ground sample of each collection was extracted with acetone and the optical density determined in a spectrophotometer. Cumulative recoveries of dyes were calculated and the mean retention time and 50% passage time were determined. The best estimates of total dye recovery were 55 to 95% with a mean ± standard deviation of 78 ± 14%. Mean retention times and 50% passage times ± the standard deviation for alfalfa hay, meadow hay and beet pulp were 25.8 ± 3.2, 32.7 ± 3.2; 33.4 ± 2.7, 36.5 ± 4.5; and 31.6 ± 8.4, 36.0 ± 9.2 hr., respectively. Copyright © 1970. American Society of Animal Science . Copyright 1970 by American Society of Animal Science