Variable speed digital ed 5 wiley mill

Diet samples were ground through a 1 mm screen using a Wiley Mill (Variable Speed Digital ED-5 Wiley Mill; Thomas Scientific, Swedesboro, NJ). Ground samples were submitted to the University of Missouri Agricultural Experimental Station Laboratories (Columbia, MO) for complete amino acid profiling using cation-exchange chromatography coupled with postcolumn ninhydrin derivatization and quantification (method 982.30 E and 988.15; AOAC, 2006 ).
Feed samples were also analyzed for gross energy at Iowa State University using an isoperibolic bomb calorimeter (model 6200; Parr Instruments Co., Moline, IL).

A feed sample (at least 300 g) was taken from each mixed batch and stored at −20 °C for later analysis. A pooled composite feed sample (approximately 200 g total) was made from equal amounts of all batches. The composite sample was ground to 1 mm particle size (Variable Speed Digital ED-5 Wiley Mill; Thomas Scientific, Swedesboro, NJ). The proximal analysis of the pooled ground samples was analyzed in duplicate for gross energy, dry matter (method 930.15; AOAC, 2007 ), ash (method 942.05; AOAC, 2007 ), and nitrogen (method 990.03; AOAC, 2007 ; TruMac; LECO Corp., St. Joseph, MI). Nitrogen analysis was calibrated using an ethylenediaminetetraacetic acid sample (LECO Corp.; 9.56% nitrogen). Crude protein was then calculated by taking the nitrogen × 6.25. An isoperibolic bomb calorimeter (model 6200; Parr Instrument Co., Moline, IL) was utilized to determine gross energy. Calibration was achieved using a benzoic acid (Parr Instrument Co.; 6,318 kcal GE/kg) as a standard.
Feed samples were submitted to the Iowa State University Veterinary Diagnostic Laboratory for vitamin A analysis (in-house protocol #9.2020). The vitamin A metabolite measured in the analysis was retinyl acetate. Analysis for retinyl palmitate was performed in triplicate, and the mean reported herein (Table 2) for the vitamin A supplemented diet and the control diet.

A feed sample (approximately 200 g) was taken from each mixed batch by taking a sample dispensed from the bin at the start of the new batch and stored at −20 °C for later analysis. Feed samples from all batches of each diet were pooled (roughly 200 g total), ground to 1 mm particle size, using a Wiley Mill (Variable Speed Digital ED-5 Wiley Mill; Thomas Scientific, Swedesboro, NJ). Ground samples were analyzed in duplicate for gross energy, dry matter (method 930.15; AOAC, 2007 ), ash (method 942.05; AOAC, 2007 ), and nitrogen (method 990.03; AOAC, 2007 ; TruMac; LECO Corp., St. Joseph, MI). For calibration, an ethylenediaminetetraacetic acid sample (LECO Corp.; 9.56% nitrogen) was used as the standard. Crude protein was calculated as nitrogen × 6.25. Gross energy was determined using an isoperibolic bomb calorimeter (model 6200; Parr Instrument Co., Moline, IL). Benzoic acid (Parr Instrument Co.; 6,318 kcal GE/kg) was used as the standard for calibration.