Appendix A. Nutrient and chemical composition of control and juniper diets (dry matter).
Dietary Component
Control Diet
Juniper diet
Dry mass (%)
47
47
Energy (kJ/g)
16.97
19.3
Nitrogen (%)
1.2
1.01
Fiber (ADF, %)
25.4
30
Lignin (%)
1.7
7.3
Nonstructural carbohydrates (%)
41.2
29.4
Sugar (%)
14.2
12.6
Starch (%)
27
16.8
Crude fat (%)
4.1
10
Total phenolics (mg/g)
3.4
12.7
Alpha-pinene (mg/g)
0.00
7.08
Notes: Dry mass was measured from a daily subsample of diet and averaged over the experimental period for each diet treatment. Energy was described in the Methods section. Fiber was determined from quantifying the acid detergent fiber (Goering and Van Soest 1970) of each diet treatment using an Ankom fiber analyzer 200/200 (Ankom, Fairport, New York, USA) and barley standard (35% ADF). Nitrogen was quantified using a Carla Erba 1108 Elemental Analyzer (Milan, Italy). Lignin, nonstructural carbohydrates, sugar, starch and crude fat were quantified by Dairy One Forage Analysis (Ithaca, New York, USA). A subsample of diet from two randomly chosen days on each diet treatment was used to estimate alpha-pinene concentration and total phenolics. Alpha-pinene concentration was quantified from ethanol extracts of diet samples using gas chromatography following procedures in Sorensen et al. (2004). Total phenolics were extracted from diets by homogenizing the diet with 85% methanol with a Polytron homogenizer (Brinkman Polytron) following procedures in Torti et al. (1995). Extracts were assayed for total phenolics using the Folin-Coicalteu method (Singleton and Rossi 1965) and a tannic acid standard (Sigma #1764 KCNT).
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