Nitrates are usually determined on forages during periods of drought stress. High levels can result in toxicity and dead animals. Plants in the sorghum family are particularly susceptible to nitrate accumulation. A fat determination would not normally be conducted on forages but might be needed on oilseeds such as cottonseeds or soybeans. Soluble protein might be beneficial when evaluating silage.
High levels can be a result of wet silage that has undergone extensive fermentation.
Lignin can give an indication of digestibility of plant fiber. High levels of lignin results in reduced digestibility and may be the cause of reduced milk on silage that was harvested last fall. Neutral detergent fiber gives an indication of intake potential of feeds. High neutral detergent fiber results in reduced intakes.