Start Date: Mar 22, 2010
End Date: Mar 21, 2015
Multiple 5-week digestibility trials will be used to evaluate the forages and diets. Feces will be collected using fecal collection bags with lambs in individual metabolism crates. In some trials, urine will also be collected. Each trial will include a short adaptation period followed by a covariate ad libitum intake and digestibility measurement using a reference alfalfa hay. The lambs will be adapted to the test forage for 14 days that will be followed by a 5-day ad libitum intake and digestibility measurement. The animals will be restricted to 1X maintenance intake for 2 days that will be followed by a 5-day restricted intake and digestibility measurement. Two groups of at least 18 lambs will be used. When not in metabolism crates, lambs will be housed in pens and fed alfalfa silage to adapt them to test forages. When in the crates, the UW-AS will measure and record feed offered and refused and fecal weights for each lamb daily. During fecal collection periods, a 20% aliquot of feces (and a 100 ml sample of urine, when appropriate) will be collected daily as well as samples of feeds offered and refused. Samples will be stored in a freezer during collection. Feeds or forages will be provided by the USDRFC. Feed and fecal materials will be processed and analyzed by the USDFRC. The UW-AS will be responsible for combining USDFRC analytical data with daily feed, refusal and fecal weights to calculate intake and digestibility. The USDFRC will be responsible for all data analysis and interpretation.