The objective of this work was to evaluate diets of spinelles cactus (54 % about) associated with different fiber sources on intake, digestibility, feeding behavior, and nitrogen balance of five male sheep, with average initialweightof 34kg. The fiber sources evaluated were: Tifton hay,soybean hulls, cottonseedandmixturestifton haywith soybean hullsandtifton haywith cottonseed.The experimental design used was a5x5Latin Square. There was no differencesfordry matter intake,organic matter, crude protein,neutral detergent fiberand total digestible nutrients. The spineless cactus associated with cottonseed promotedone greater digestibility to ether extract. The soybean hulls afforded coefficients of digestibility of dry matter and neutral detergent fiber higher than to Tifton + cottonseed. The treatment tifton hay and tifton hay + soybean hulls showedgreaterdigestibility ofcrude protein compared to cottonseed. The treatment with spineless cactuswith soybean hulls showed higher mean of nitrogen excretion of feces than the others. Higher value of nitrogen excretion in the urine was from tifton hay + cottonseed.The spineless cactuswithsoybean hullsresultedinlessrumination timeandtotalchewing. It is recommended the use spinelles cactus associated with tifton hay and soybean hulls as fiber sources in the sheep diets.
byproducts; digestibility; intake; rumination