aiming to evaluate the potential of by-products coming from the production of biodiesel (palm oil, peanuts and sunflower cakes) replacing soybean meal, were evaluated the feeding behavior and bioclimatology of holstein-zebu steers fed diets with this byproducts. were used four rumen canulated holstein-zebu steers, kept in individual pens and distributed in a 4 x 4 latin square with repeated measures on the time. the experiment lasted 88 days and the animals were fed tifton-85 hay and concentrate ration with soybean meal or one of the following cake: palm kernel, peanuts or sunflower, which constituted the four treatments. ingestive behavior was assessed by observation and recording of daily time spent on eating, ruminating and idle. the bioclimatological behavior of the animals was evaluated through the following measurements: respiratory frequency (rf), heart frequency (fh) and rectal temperature (rt). the time spent for ingestion and rumination did not differ (p>0.05) between diets, however, animals fed the diet with palm kernel meal, spent more time in idle (p<0.05). there was difference for the physiological parameters only for heart rate (hr), and the diet without additional cake that provided the greatest value. the substitution of soybean meal with palm kernel meal coming from the production of biodiesel in the diet of steers affected the ingestive animal behavior.