2.4.1. Diet Analysis

Nitrogen content in the diets was determined using the combustion method [26], Method 990.03, with a nitrogen analyzer (Model Leco CN828 Carbon Nitrogen Determinator, St. Joseph, MO, USA) and CP was calculated as N × 6.25. The ether extract in samples was determined after hexane extraction [26] using Method 920.39 in an Ankom XT10 Fat Extractor system (Macedon, NY, USA). The metabolizable energy content of diets was determined at the Central Testing Laboratory, Winnipeg, MB, using their standard laboratory procedures.