Development of a novel stall design for dairy cattle: Part I. The effect of an increased slope on lying behavior, rumination, cleanliness, and preference

•The longitudinal slope of the stall aids in cleanliness and positioning dairy cows.•An increased stall slope (9.3%) was compared to a standard stall slope.•Increasing the stall slope marginally affected lying behavior.•Increasing the stall slope did not affect cow cleanliness or preference.•Results suggest increasing the stall slope did not interfere with stall use.