Animal Feedstuffs and Roughages

• Feedstuffs are classified based on their origin, nutrient composition, and use in animal feeding

Dry roughages

• Includes all forages and roughages cut and cured
• Includes hay, straw, fodder, and stover

Hay

• Legume hays (alfalfa, clover) are higher in protein, energy, and calcium than grass hays (timothy, bromegrass)
• Quality is affected by maturity at harvest, harvesting and storage methods

Straw

• Straw is the mature, dry stalks of grains after the seeds have been harvested
• Low in nutrients and digestibility, primarily used as a source of fiber

Fodder

• Fodder refers to the entire corn or sorghum plant harvested at maturity and dried
• Provides more nutrients than straw but less than hay

Stover

• Stover is the mature corn or sorghum stalks and leaves remaining in the field after grain harvest
• Similar in nutritive value to straw

Pasture, range plants, and forages fed fresh

• Includes all forages harvested or grazed in a fresh state

Pasture

• Pasture is managed grassland or planted forages used for grazing
• Nutritive value varies with plant species, stage of maturity, and soil fertility

Range plants

• Range plants are native grasses, forbs, and shrubs grazed by livestock on rangelands
• Nutritive value varies greatly depending on plant species, season, and grazing management

Forages fed fresh

• Green chop is freshly cut forages that are fed to livestock
• Can provide high levels of nutrients if harvested at the proper stage of maturity

Silages

• Silage is produced by ensiling forages or other feedstuffs under anaerobic conditions
• Fermentation produces acids that preserve the feed

Corn silage

• Corn silage is a common feed for ruminants
• High in energy and relatively low in protein

Legume silage

• Legume silages (alfalfa, clover) can be high in protein and energy
• More difficult to ensile than corn silage due to higher buffering capacity

Grass silage

• Grass silages can be a good source of fiber and energy for ruminants
• Quality depends on the stage of maturity at harvest

Energy feeds

• Includes cereal grains, byproduct feeds, and fats
• High in energy and relatively low in fiber

Cereal grains

• Corn, barley, oats, wheat, and sorghum are commonly used as energy feeds
• Corn is the most common energy feed in the US due to its high energy content and availability

Byproduct feeds

• Byproduct feeds from the milling and processing industries
• Examples: wheat middlings, corn gluten feed, distillers grains

Fats

• Fats and oils are added to diets to increase energy density
• Can improve palatability and reduce dustiness

Protein supplements

• Includes plant and animal protein sources
• Contain high concentrations of protein

Plant protein sources

• Soybean meal is the most common plant protein supplement
• Other plant protein sources: cottonseed meal, canola meal, sunflower meal

Animal protein sources

• Animal protein sources: fish meal, meat and bone meal, dried milk products
• Used in diets for non-ruminants and young animals

Mineral supplements

• Provide essential minerals that may be deficient in basal diets

Macro-minerals

• Calcium, phosphorus, magnesium, potassium, sodium, chlorine, and sulfur
• Commonly supplemented in livestock diets

Trace minerals

• Iron, zinc, copper, manganese, iodine, selenium, and cobalt
• Often provided in trace mineral premixes

Vitamin supplements

• Provide essential vitamins that may be deficient in basal diets

Fat-soluble vitamins

• Vitamins A, D, E, and K
• Stored in the body, so toxicity can occur with excessive supplementation

Water-soluble vitamins

• B vitamins and vitamin C
• Not stored in the body, so daily supplementation is necessary

Additives

• Includes a variety of non-nutritive substances added to diets to improve performance, health, or feed quality

Antibiotics

• Used to improve growth rate and feed efficiency in livestock
• Use is regulated due to concerns about antibiotic resistance

Probiotics

• Live microorganisms that can improve gut health and digestion
• Often used in diets for young animals

Enzymes

• Added to diets to improve the digestibility of certain feed components
• Examples: phytase, xylanase, cellulase

Buffers

• Used to neutralize acids in the rumen and prevent acidosis
• Commonly used in diets for dairy cattle

Antioxidants

• Added to diets to prevent oxidation of fats and vitamins
• Examples: vitamin E, selenium, ethoxyquin

Hormones

• Used to improve growth rate and feed efficiency in livestock
• Use is regulated due to concerns about human health

Flavors

• Added to diets to improve palatability and feed intake
• Especially useful in diets for young animals or animals with reduced appetite