Sunflower cake in diets for lambs: Intake, digestibility, nitrogen balance and rumen parameters

Abstract

The present study objective was to determine the intake and digestibility, nitrogen balance and ruminal fermentation parameters in sheep fed diets containing levels of substitution of soybean meal for sunflower cake. The diets consisted of five levels of protein soybean meal (0, 25, 50, 75 and 100 %) by sunflower cake. Diets were formulated with 12.6% CP, respecting the roughage: concentrate ratio of 40:60, as source roughage was used hay Tifton-85 and as food concentrates used were: corn, soybean meal, sunflower cake and premix mineral vitaminic. Five lambs crossbred castrated with average weight of 29.64 ± 2.94 kg were used, distributed in latin square 5 × 5. There were no differences in intake dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and total digestible nutrients. The intake of ether extract (EE) and non-fiber carbohydrates (NFC) were increased linearly. For intake of total carbohydrates (TC) was observed equation linear in relation to body weight and metabolic weight and quadratic when expressed in g day -1 with peak in 377.1 g kg -1 replacement of soybean meal by sunflower cake. There were no differences in digestibility DM, OM, CP, NDF, NFC and TC. There was a linear increase in the digestibility of ether extract (EE). The intake, feces, urinary and retained nitrogen were not influenced by levels of substitution of soybean meal by sunflower cake in the diets. For the pH of liquor ruminal there was no difference for the different levels of substitution of soybean meal by sunflower cake. However, ruminal pH differed with respect to collection time for all experimental diets. There was no effect on diets and sampling time for concentration of NH 3 -N. It was concluded that the sunflower cake can be used as an alternative food to replace soybean meal up to 100% in concentrate mixture unless there are changes in the rumen parameters, balance of nitrogen, intake and nutrient digestibility.