Feed costs are the largest expense on most dairies. In addition to lower feed costs, byproducts can be used to increase the nutrient density in a dairy ration and extend forage or grain inventory. Careful consideration should be given when selecting byproducts to use.
    Keep in mind some byproducts are extremely high in certain nutrients, such as water, sulfur, phosphorus, sodium or chloride. Many byproducts have significant variation from source to source and, in a few cases, variation within a facility. Closely monitor consistency and quality.
    When assessing the economics of byproducts, make sure to compare feeds on a dry matter basis. Account for associated costs, such as shrink, delivery, handling, processing or chemical analysis. Shrink is defined as the loss of feed that occurs from the point of purchase to what is actually consumed by the animal. Shrink can range from 2 to 20 percent, depending on the storage structure and physical nature of the commodity. Limited shelf life can lead to spoilage with certain wet byproducts in the summer months. Spreadsheets are available to establish a value per ton based on the nutrient analysis of a byproduct compared to a list of reference feeds.
    By products can be divided into the following five primary categories.
    Carbohydrate byproducts: These ingredients provide soluble sources of sugar or starch. These commodities can serve as a potential grain extender and energy source beyond corn. Examples include whey permeate, molasses, bakery products, cereal fines and potatoes waste.
    Protein byproducts: These commodities come either from plant or animal origin. Be sure to evaluate cost per unit of supplemental protein. Consideration should also be given to specific amino acid contribution and level of bypass protein. Commonly used protein byproducts include soybean meal, canola meal, corn distiller grain, corn gluten meal, brewers grain, blood meal, and meat and bone meal.
    Non-forage fibrous byproducts: Options include highly digestible fiber sources, allowing for reduced starch while maintaining energy levels. These commodities are commonly used to replace forages due to inventory or quality concerns. Upper limits of these byproducts may be dictated by physically effective fiber. Common feedstuffs in this category include cottonseed, beet pulp, corn gluten feed and soy hulls.
    Fat-enriched byproducts: Consider using fat from oilseeds first before animal fats, based on economics. Carefully evaluate digestibility and value of fat relative to cost. The physical form of the commodity can impact the rate of fat availability. For example, corn distiller grain in a meal form has a faster rate of fat availability compared to cottonseed where the fat is encapsulated in the seed. Other forms of fat byproducts include vegetable oil, tallow and choice white grease.
    High-fiber, low-digestibility byproducts: These are ingredients that may be considered for heifer diets or lower-energy dry cow diets. Examples include oat hulls, cottonseed hulls and malt sprouts.
    Byproducts can be a viable alternative to dairy rations to reduce ration costs, increase nutrient density, or extend forage or grain inventory. Although they may seem like a good deal, recognize the significant cost associated with variation and shrink. Work with your nutritionist to evaluate specific byproducts for individual farm needs.
    Barry Visser is a nutritionist for Vita Plus.