Digestion of Soybean Meal in Alpacas

Abstract

The objective of this experiment was to determine the degradation parameters of grass hay (GH) supplemented with soybean meal (SBM) and to determine the effects of SBM on compartment 1 (C1) ammonia (NH3-N) and volatile fatty acid (VFA) concentrations in alpacas. Four C1 fistulated adult male alpacas (7±1.5 years old; 61±5 kg BW) were housed in metabolism crates and received water ad libitum during the treatment periods of this study. The GH and SBM treatments were fed at 0700 every day. Treatment periods were for 14 d in which GH or SBM treatments were randomly allocated to each alpaca. On d14 volatile fatty acids (VFA), pH and NH3-N were determined at 1, 3, 6, 10, 14, 18 and 24 hrs post feeding. C1 degradation of GH and SBM was determined with the alpacas being fed GH only and the samples incubated for 0, 2, 4, 8, 14, 24, 48 and 72 hrs. Dry matter (DM) and crude protein (CP) degradation were determined and divided into three categories: a = immediately soluble; b = non-soluble but degradable; and u = non-degradable/unavailable, potential extent of degradation (PE), degradation rate (c) and effective degradation (ED; kp = 5.5%∙hr-1). Total DM intake was different between the two treatments, while CP intake was increased (72.5 to 191.0 g/d; P