Animal nutrition Plant and animal tissues + Feedstuff

The National Research Council

(NRC) has organized feedstuffs into categories based on their chemical compositions, physical forms and use as a feed.

Rotational grazing

, plants get a recovery period for regrowth, it decreases over- and under-grazing, feces are distributed more evenly throughout the pasture, and stocking rate is greater than with continuous grazing. The disadvantages are that it requires more capital input for fences and water system, and requires more management input.

Pasture Management

- controlled grazing for undergrazing and overgrazing Increases in height of tall growing grasses may also drive out lower growing plants. Tall growth of orchardgrass would shade white clover making it difficult for the clover to survive in the pasture. Overgrazing weakens the plant due to less leaf surface area for photosynthesis, allows weed to infiltrate the pasture, and contributes to erosion. Three grazing management systems are continuous grazing, rotational grazing, and strip grazing or more intensive rotational grazing.

cell walls are composed of

20-40% cellulose 10-40% Hemicellulose 5-10% lignin protein Pectin The carbohydrates associated with the cell wall are termed structural carbohydrates and include cellulose, hemicellulose, and pectin. Cellulose and hemicellulose form a greater proportion of the cell wall than pectin. The other major component is lignin. Lignin is not a carbohydrate but is usually discussed with the carbohydrates because of their association in the cell wall. These components are also considered plant fiber

pasture

A pasture is an area of land on which there is a growth of forage that animals can graze. Use of pasture tends to lessen feed costs and, if well-managed, provides a good source of high quality protein, vitamins and minerals Hay and silage are two ways of preserving forage. Even under the best conditions, there is some nutrient loss when pasture is preserved for later feeding.

Forages and roughages

Alfalfa Bermuda grass Corn silage Cotton by-product Cottonseed hulls Fescue grass Oat hulls Orchardgrass Peanut hulls Rye grass Soybean hulls Switch grass Timothy grass

Using Forages - Hay

Although the most economical and nutritious way to use forage is to graze, year round grazing is not possible in most locations. Hay is forage harvested during the growing period and preserved by drying. It retains much of its nutritional value during storage. The objective in making hay is to reduce the moisture content of the hay to 10 to 15% and thus retard enzymatic or microbial degradation during storage. The quality of hay will vary with the species of plant (grasses vs legumes); stage of maturity at which it was cut; and general handling and weather during cutting.

The categories of protein supplements are

Animal protein supplements Plant protein supplements Nonprotein nitrogen

Animal Protein Supplements

Animal protein supplements are derived from four major industries: Meat packing and rendering Fish and fish processing Poultry and poultry processing Milk and milk processing Products from meat packing and rendering operations include meat meal, meat and bone meal, blood meal and plasma protein.

Energy feeds

Barley grain Corn grain Milo (sorghum) grain Oat grain Rice grain Wheat grain Beet pulp Citrus pulp Cottonseed (whole) Molasses Oils Potatoes Wheat middlings

As Fed and Dry Matter Basis

Because many feeds vary significantly in moisture content, the chemical composition of feedstuffs is often expressed on a 100% dry matter basis rather than an as fed basis. As fed (AF) basis = the feed as it is fed to the animal (dry matter + water) 100% Dry matter (DM) basis = the feed not including the water, includes all the nutrients in the dry matter In general remember: If you know the amount of feed DM you must "add water" to get the As fed amount of feed, therefore, the As fed amount will be greater. If you know the As fed amount of feed, you need to "remove the water" to get the amount of DM, therefore, the DM amount will be smaller. The concentration of a nutrient is greater when expressed on a 100% dry matter basis. This is because the water has been removed but the amount of the nutrient is the same. Therefore, it is concentrated in the dry matter and is a greater percentage of the total.

Beet Pulp

Beet pulp is the residue after extraction of sugar from sugar beets. It is dried and then shredded or pelleted. Beet pulp is very palatable and added to the diets of many species. It is frequently added to dog and cat food. Beet pulp is often soaked to rehydrate for moist feeding when fed separately. Beet pulp contains insoluble fiber. The insoluble fiber (NDF) increases transit through the GI tract and has a laxative effect.

Potential Problems for Grazing Animals

Bloat nitrate toxicity grass tetany Fescue toxicosis

Bloat

Bloat is associated with legume pastures particularly, alfalfa and clover. Ruminants are more susceptible to bloat than horses because of their anatomy. The normal eructation process is prevented due to foam accumulation in the rumen which entraps gas within the rumen leading to distension (Figures 7, 8). Because the animal is unable to eructate there is no way to relieve the gas pressure. The rumen continues to distend and ultimately the condition can result in suffocation and death. Prevention is the best approach. Prevention strategies include use of anti-bloat mineral blocks that contain poloxalene on pasture, limiting grazing time, and use of mixed pastures. Agents to destabilize the foam can be administered through a stomach tube (poloxalene, corn oil) if an animal is in distress.

Protein supplements

Blood meal Brewers grains Corn gluten meal Cottonseed meal Distillers grains Fish meal Kidney beans Lentils Meat meal Meat and bone meal Poultry by-product meal soybean meal Amino acids- considered nonprotein N

Cereal Grains

Cereal plants are annual grasses. The whole seeds of these plants are the cereal grains. The seed may be processed yielding a number of seed co-products. The major industries that process grains for human consumption and produce co-products for use in animal feeds are the brewing, distilling, wet milling and dry milling industries. Some of the co-products are energy feeds; however, some are protein supplements or roughages. In addition, production of biofuels, specifically use of corn to produce ethanol, produces distillers grains (a protein supplement) for animal feed The vegetative portion of the cereal plant can provide pasture (wheat, rye), straw (wheat) and silage (corn, sorghum).

citrus pulp

Citrus pulp is the product remaining after juice is extracted from citrus fruits. The fiber it contains is a combination of soluble and insoluble fiber. Soluble fiber and insoluble fiber have different effects in the GI tract. The insoluble fiber increases the rate of transit through the GI tract, as noted above. Soluble fiber increases viscosity. It also decreases plasma cholesterol concentration which is of interest in humans and companion animals. Both types of fiber improve health of cells lining the colon if the fiber is fermentable.

ways to optimize forage pastures

Cool season grasses have a period of rapid growth in early spring and re-growth in the fall. They are relatively dormant in summer. In contrast warm season grasses have their period of most rapid growth in the summer and are dormant in the cooler months. One can take advantage of this to extend the grazing season in two ways. One is to plant mixed pastures, containing more than one forage type, so forage is available for most of the year. The second is to plant a cool season grass in one pasture and warm season grass in another pasture. Animals can be moved among pastures to match periods of forage growth.

Components of Plant or Animal Tissues: divisions

Dry and wet: dry has all components except water The dry matter can then be divided in inorganic and organic components. The inorganic components are the minerals. The organic components include the remaining classes of nutrients: carbohydrates, lipids, protein and other nitrogen containing compounds and vitamins.

Fats and Oils

Fats are solids at room temperature and oils are liquids at room temperature. They have 2.25 times the energy value of carbohydrates per unit weight. Animal fats include lard (pork fat), tallow (beef fat) and poultry grease. Vegetable oils are extracted from different seeds such as corn (corn oil), soybean (soybean oil), or cotton (cottonseed oil). Addition of fats or oils increases the energy density of the diet. It is included in the diets of most animals at some point in their life cycle. For example, it is added to the diets of dairy cows in early lactation and horses during endurance exercise. The amount added varies greatly depending on species. Fats and oils decrease dustiness and enhance palatability of a diet. They are also a source of essential fatty acids.

Seeds

For many seeds, removing the hulls is the first step in processing. The hulls are a roughage and are incorporated into the diet of many animals. Examples are oat hulls, peanut hulls, and soy hulls.

Forages vs. Roughages

Forages are plants grown or used for feeding animals. Forages are defined as vegetative materials in a fresh, dried, or ensiled state. It includes the leaves, stems, and stalks of plants. The term forage is usually used to describe the whole plant rather than a part of the plant such as the seed. Pasture, hay, and silage are examples of forages Roughages are bulky feeds with a low weight per unit volume. Bulky feeds are high in fiber. Roughages include items such as peanut hulls or cottonseed hulls which are not forages, silage, hay, pasture, haulage, green chop. The common feature of both forages and roughages is that they are high in neutral detergent fiber (or cell wall).

Feeding ruminants v herbivores

In general ruminants have a greater ability to digest forages than other herbivores such as horses. When feeding domestic animals, therefore, higher quality forages are usually fed to horses than to ruminants.

Cottonseed meal

It is fed in limited amount to all animals because of gossypol, which is a toxic substance in the seed. Ruminants tolerate more than other animals because the microorganisms in the rumen decrease its toxicity.

Corn gluten meal

It is often included in diets of companion animals.

Fish meal

It is the dried residue that remains after oil is extracted from fish (Figure 1). Menhaden fish meal is common Fish meal contains approximately 67% CP and is of high quality.

Molasses

Molasses is a coproduct of manufacturing of sugar from sugar cane (cane or blackstrap molasses) or sugar beets (beet molasses). It is available in liquid or dehydrated form. Molasses is 50 to 60% sugar and high in mineral content. It is added to diets to enhance palatability, decrease dustiness and may serve as a vehicle for medications or other additives. A relatively small amount, 3 to 5%, is added to diets. Inclusion at levels exceeding 10% can lead to digestive upset.

Differences Between Plant and Animal Tissues How is energy stored

Plant cells also have the ability to synthesize amino acids from inorganic N (nitrates) Plant tissues contain a much higher percentage of carbohydrates than animal tissues. In contrast animal tissues contain a greater percentage of fat. Concentration of protein is also greater in animal tissues. Mineral content is relatively similar but slightly higher in animal tissues. Energy storage differs in that animals store energy as fat (triglyceride) whereas plants store energy in the form of carbohydrate (predominantly starch). Animal cells have a membrane that is composed of lipid (phospholipid bilayer) and protein. Cells of plants have a cell wall which contains a high portion of carbohydrates. The cell wall contains structural carbohydrates which give it rigidity as the plant develops. Proteins are an important part of animal tissues and form the structure of muscle, skin, hair and feathers.They also function as enzymes important to metabolism. In whole plants, proteins function as enzymes and have some structural and storage role but are not as prominent as in animals. If one looked at a part of a plant such as a seed, it has a greater concentration of protein than the whole plant. Although the amount of mineral is similar in plant and animal tissues the specific minerals differ. The two major minerals in animals are calcium and phosphorus. These two minerals are predominantly found in bone but have other functions in the body. The two major minerals in plants are silicon and potassium. The silicon content in grasses contributes to wearing down the teeth as grazing animals grind the grasses.

Plant Protein Concentrates

Plant protein supplements include the oilseed meal byproducts and by-products from other industries that process grains for human consumption. In both cases, the protein supplement represents the material remaining after processing. Oilseeds are grown primarily for the oil. The seeds are dehulled and the oil is extracted. Heat is used in the extraction process. Because the amount of protein in the seed doesn't change, following extraction of the oil, the concentration of protein in the residue increases.

Roots and Tubers

Roots such as beets, turnips, and carrots are high in sugars. Tubers, which include potatoes, are high in starch.

Cotton

Roughage Following harvest cotton is transported to the cotton gin. The first step in processing cotton is removal of the seeds and plant material. The seeds can be processed further by removal of hulls and extraction of oil producing cottonseed meal. The cotton fiber is separated into cotton for textiles and cotton fiber by-product. The by-product contains short fibers. Look at photo Cottonseed hulls are an important roughage source for dairy and beef cattle in the south. They are palatable. They contain approximately 3.8% CP (crude protein). Cotton fiber by-product includes by-products of both the ginning and milling of cotton. It contains mostly cellulose and approximately 4 to 9% CP. It is a roughage that is fed to beef cattle.

Using Forages - Silage

Silage is fed mostly to dairy and beef cattle. Corn silage is most common. Corn for silage is cut when the moisture content is 60-70% (Figure 1). The forage is chopped into small pieces, packed into a silo and sealed. Because forage for silage is cut and immediately placed in the silo, greater nutrient value is preserved than when making hay. Silages or haylages are fermented forages stored under anaerobic (without oxygen) conditions in a silo. The conditions provide an environment where microorganisms ferment the soluble carbohydrates in the forage producing lactic acid, and other short chain fatty acids. As the acids are produced, the pH decreases until it is around 4.0-4.5. As the pH decreases, microbial growth is inhibited and as long as the conditions remain anaerobic, the silage is relatively stable.

cost of feedstuff

Taking a representative sample of the feedstuff for chemical analysis is a good idea before incorporating it into a diet. Products that are wet, for example brewers grains, are usually only economical if they are produced nearby. Otherwise the cost of transportation is too great to justify using the feedstuff. Wet products also have a shorter self-life than dry products. This may be of greater concern in the summer months than in the winter. When paying for a feedstuff the cost should be evaluated per unit of crude protein or energy. A feedstuff may be very cheap per ton but if it doesn't contain the nutrients or energy needed it may not be a good choice. Other co-products are quite expensive, produced in large quantity, and have greater quality control to reduce variation. This is particularly true of some of the co-products that are classed as protein supplements.

Continuous grazing

The advantages are that it requires less management and capital input is minimal. The disadvantages are that animals tend to graze in patches resulting in both over- and under-grazing and lower forage quality. Feces are concentrated in areas around the pasture rather than being distributed evenly. Stocking rate (how many animals your land will support) is lower than with other systems.

Nutrient Composition of Grains

The cereal grains are a good source of energy but are relatively low in crude protein, ranging from 10 to 15%. Corn has the lowest and wheat the highest CP concentration Oats and barley have lower energy content because of their hulls and the greater content of fiber Carbohydrates are the major component of the grain and are approximately 70% of the dry matter. Starch is the primary carbohydrate. Lipids are low and vary from 1 to 6%. These are oils containing many unsaturated fatty acids which have double bonds. Grains are low in calcium. They are high in phosphorus; however, much of the phosphorus is in the form of phytic acid (or phytate). This form is unavailable for simple stomached animals. Ruminants are able to use this form of phosphorus because the microorganisms in their rumen can hydrolyze the compound. The enzyme phytase can be added to the diets of other animals (pigs, poultry) to increase availability of the phosphorus in phytic acid. Grains are relatively low in vitamins. Corn is high in β-carotene which is a precursor of vitamin A.

Fermentation

The fermentation process takes about 3 weeks. When the silo is filled there is an initial aerobic phase. During this time plant respiration continues. Plant enzymes and aerobic bacteria convert readily available carbohydrates to heat, water, and carbon dioxide. This results in depletion of the oxygen and heating of the silage over the first 48 hours. Lack of oxygen inhibits mold growth. As the oxygen depletes, anaerobic bacteria multiply and ferment starches and sugars. Early on in the fermentation process bacteria that produce acetic acid predominate. As time progresses this changes to bacteria that produce lactic acid. Lactic acid is the major acid in high quality silage and will be 4 to 10% of dry matter. When fermentation is complete, the pH will be 3.5 - 4.5. This prevents bacterial growth. Silage is stable for years if properly fermented and oxygen is kept out. see photo

International Feed Number (IFN).

The first number in the IFN sequence represents the category in which the feed is classified, e.g., 4-02-931 is an energy feed. The major classifications are: 1. Dry roughages and forages 2. Pasture 3. Silage 4. Energy feeds 5. Protein supplements 6. Mineral supplements 7. Vitamin supplements 8. Nonnutritive additives

Making Hay

The four steps to making hay are to mow, cure, rake into windrows, and collect and store—usually as bales. cure- use a tedder to decrease moisture content As the forage is cut it is fed through the rollers which split or crush (condition) the stems. This decreases drying time. Some mowers cut and windrow in one step. Moisture should be 15% or less when baled. that maximum feeding value per acre is reached 10 to 15 days before maximum yields Hay will vary depending on the crop from which it is made, the stage of cutting, handling during processing, extent of weather damage while drying, and manner of storage. Legumes are more susceptible to leaf shatter when raking if the forage is too dry. Rain will result in loss of soluble nutrients such as sugars, starches and proteins. If hay is stored outdoors and uncovered there are significant losses. Placing hay on a pallet to store it off the ground is an important step to maintain quality during storage. Stacking bales and covering with a tarp will prevent loss of quality with storage.

crude fiber

The process to measure crude fiber (CF) was developed in the late 1800's to determine the portion of feedstuffs that was not digestible. - contains the cellulose and most of the lignin

Pasture Quality

There are several factors that affect the value of pasture including the soil and fertilizer, plant species, stage of maturity, and grazing. The nutrients required in greatest amount by plants are nitrogen, phosphorus, and potassium. proper pH Soils are often acidic. Addition of lime increases the pH of the soil to allow plants to increase uptake of nutrients. A soil pH that is too high (alkaline) also decreases availability of some nutrients and plant growth. - legumes are better - mixed pastures Pastures containing different types of grasses that mature at differing times, provide more uniform production of forage for a longer time. maintain the forage in the vegetative stage to avoid grazing mature pastures

Silos

There are upright silos, horizontal silos and bag silos. Upright silos are either of the concrete stave type or glass lined. Forage is blown to the top of the silo through a tube on the side of the silo and falls into the silo. Forage is packed by gravity. Horizontal silos are either above the ground (bunker silo) or below the ground (trench silo). These are packed with a tractor. Plastic bag silos are temporary silos that are packed as they are filled.

In lumen of plant cells

These include sugars and proteins and are termed readily available nutrients.

crude protein

This term derives from the chemical analysis used which measures N content. The N content of a feedstuff is converted to CP by multiplying the value by 6.25. This factor assumes that the protein is 16% N

Nonprotein Nitrogen

Urea is the most common source. Urea is only fed to ruminants. Bacteria in the rumen convert the urea to ammonia. Dietary carbohydrates provide energy and a carbon source that the bacteria can use to synthesize amino acids. Urea is often fed with molasses as a readily available source of carbohydrates. Only a limited amount of urea is fed. Excess urea and consequently excess ammonia produced from urea by rumen microorganisms results in increased rumen ammonia concentration, increased rumen pH, and increased ammonia absorbed from the gastrointestinal tract. If the quantity of ammonia absorbed exceeds the ability of the liver to detoxify ammonia then convulsions, respiratory difficulty, bloat, and death can follow. Ammonium products are fed mostly to ruminants only. They include ammonium phosphate and ammonium chloride. Amino acid supplements are in the NPN category. The ones most commonly included in the diet are methionine, lysine and threonine. Supplemental amino acids are commonly added to feeds for simple-stomached animals

The six classes of nutrients are:

Water Minerals Protein and other nitrogen (N) containing compounds Lipids Carbohydrates Vitamins

Co-products of Grain Milling

Wheat bran and wheat middlings are produced during the milling of wheat for flour. The co-products are distinguished by both their crude protein (CP) and fiber concentration. Wheat bran contains the outermost layer of the grain. It is bulky and has laxative properties. Wheat middlings are used as a grain replacement.

Whey Products

Whey products are derived from the liquid remaining after processing milk in making cheese. It may be in liquid or dry form. It is approximately 14% CP in DM. It contains a significant amount of lactose and mineral which can have laxative properties if included in diets in unlimited amount. It is often included in diets of young growing animals following weaning.

Seeds of Other Plants

Whole cottonseed is the seed of the cotton plant before extraction of the oil or any other processing. This contains approximately 22 to 24% CP. It is classed as an energy feed or a protein supplement because the percentage CP is very close to 20%. It is fed to dairy cattle in early lactation to add additional energy to the diet without adding more grains.

Other oilseed meals

anola meal, sunflower meal, safflower meal, and linseed meal are also used in animal feeds.

Feedstuffs are loosely defined as

any component of a diet, of natural or artificial origin, that has useful or nutritional value when properly prepare

Protein supplements

are feedstuffs containing more than 20% crude protein and may be of plant or animal origin.

neutral detergent fiber

better way to describe fibers components than crude fiber specifically for use with forages. This procedure measures neutral detergent fiber (NDF) and acid detergent fiber (ADF). The NDF includes cellulose, hemicellulose, and lignin and approximates the cell wall. Dry matter intake of forages is related to the cell wall content. An increase in NDF will limit intake. The ADF portion includes cellulose and lignin only. It is inversely related to digestibility of the forage. As ADF increases in the DM, digestibility decreases. It is the content of lignin in the ADF that is the most indigestible component. Lignin also forms cross-links with cellulose which decrease the digestibility of cellulose. Acid detergent fiber is similar to crude fiber but ADF more completely measures the cellulose and lignin.

Regulations for Feeding Protein Supplements of Animal Origin

bovine spongiform encephalopathy (BSE, mad cow disease) -prion A similar disease in humans is variant Creutzfeldt-Jakob Disease (vCJD) The FDA rule stated that proteins derived from mammalian tissues are prohibited in ruminant feeds. This included meat meal, and meat and bone meal. It excluded milk products, porcine or equine protein, and blood and blood products Examples of high risk products are the brain and spinal cord of cattle greater than 30 months of age.

Concentrates

can be high or low in protein and are usually separated into two categories based on their protein content. Carbonaceous feeds are concentrates that have relatively low protein content, less than 20%. This category includes the cereal grains. Corn is the major animal feed in this category. Nitrogenous feeds are concentrates containing more than 20% crude protein. Soybean meal is the most commonly used animal feed in this category. The nitrogenous concentrates (high protein) are part of a broader category of feedstuffs termed protein supplements.

General Functions of Nutrients

carbohydrates, lipids, and proteins provide energy. These nutrients are oxidized by cells to produce ATP for cellular processes. promote growth and maintenance of body tissues. This refers to the nutrients that form part of the body structure. Proteins, lipids, minerals, and water regulation or control of body processes. All of the classes of nutrients except carbohydrates perform this role.

Meat and bone meal

contains added bone such that the product contains more than 4.4% P. The Ca content is limited to no more than 2.2 x the phosphorus content. It contains 45-50% CP. Ca and P must be labeled.

Dried blood meal

contains all the components of blood including cells and plasma. It contains 80-85% CP. It has low palatability and is added to diets at a low percentage (less than 5%).

major grass categories

cool and warm season grasses. Cool season grasses are also referred to as C3 plants or temperate plants. There are two major photosynthetic pathways. The term C3 plant means that the first product in the pathway of photosynthesis has three carbon atoms. These grasses grow best at temperatures less than 80 F. They have two periods of growth during the year. They store carbohydrate in roots for re-growth although re-growth is lower in soluble carbohydrate and therefore, lower in quality. Cool season grasses mature at a slower rate than warm season grasses and have slower decline in quality with aging than warm season grasses. Warm season grasses are also referred to as C4 plants or tropical plants. The first products in the pathway of photosynthesis have four carbon atoms. As a result, C4 plants are more efficient in use of solar energy, carbon dioxide and water to make carbohydrates. They grow best at 95-105 F. They have deep root systems and are better adapted to water stress than cool season grasses. They are also lower in protein and higher in fiber than cool season grasses.

Soybean meal

has the greatest nutritive value of any plant protein. It is the most common protein supplement and is incorporated into the diet of most animals. The concentration of protein is either 44 or 48% depending on the amount of hulls in the final product.

Forage Quality

he leaves are more nutritious than stems. Stems have more structural carbohydrate in the cell wall whereas leaves have more soluble carbohydrate which has greater digestibility. A measure that is used to estimate forage quality is the leaf:stem ratio. A greater leaf:stem ratio indicates forage of higher quality. Young plants are more nutritious than old plants. As plants age the cell wall takes a greater portion of the total cell and digestibility decreases. The concentration of protein decreases also with aging. Legumes are better quality than grasses when compared at the same maturity. Legumes have a higher leaf:stem ratio, are more digestible, and have a greater concentration of protein, calcium, and magnesium than grasses.

Grass stage of maturity

if allowed to mature, grasses undergo several stages of growth in the spring (Figure 2). These are 1) leafy vegetative; 2) boot with seed heads enclosed in leaf sheath; 3) heading when the seed heads begin to show; and, 4) bloom. Cellulose and lignin (both part of the cell wall) contents increase as the plant matures while digestibility decreases. Concentration of protein also decreases as the grasses head out. look at pictures

problems with silage

if silage is too wet there is nutrient loss due to seepage. High moisture also decreases the temperature of the silage during heating resulting in greater growth of bacteria that produce butyric acid. This results in poor quality silage with a final pH that is less acidic. On the other hand, if the forage is too dry it will be hard to pack resulting in improper fermentation and mold growth.

Grass tetany

is associated with low magnesium intake or interference with use of magnesium in the body leading to low blood magnesium concentration. High N fertilization, cool weather, and rapid plant growth intensify the problem. It is usually associated with rapid growth of cool season grasses in the spring which results in a plant that is relatively low in magnesium, high in potassium, and high in organic acids which may decrease absorption of magnesium from the rumen. Ruminants are most susceptible. Symptoms include incoordination, convulsions, and death. Supplementation of animals on pasture with magnesium oxide will prevent the condition.

Dried skim milk

is derived from milk and milk processing. It contains 35% CP and is of high quality. It is expensive. It is usually included in the diets of young animals.

Spray-dried plasma protein

is derived from the plasma portion of blood. It is included in the diet of young animals. In young pigs, inclusion of plasma protein stimulates intake. It contains 78% CP.

Meat meal

is processed from carcass trimmings and condemned carcasses. It includes organs, bone, and fat It is rich in minerals especially calcium (Ca) and phosphorus (P).

Strip grazing

is the same as intensive rotational grazing. Movable electric fence can be used to provide many smaller grazing areas or paddocks. Animals are usually moved after several days of grazing. The advantages are better use of forage, less selection, and greater stocking rates. The disadvantages are the cost of fencing and water systems, requires more management, and increased labor cost.

For a legume or grass

it could be fresh grass (pasture) or dry (hay).

Co-products

may be economical as a feedstuff; however, there are considerations in addition to cost before deciding which ones to use. Among these are variation, palatability, transportation cost, cost per unit nutrient, shelf-life, continued availability, and potential toxic components. Because the co-product is not of primary concern in processing variation in the feed ingredient from batch to batch can be quite large. An example here is distillers grains.

Fescue toxicosis

occurs in cattle, sheep, and horses. Kentucky 31 is the most prevalent variety of fescue. It is hardy due to the presence of a fungus that lives inside the leaves, stems and seeds. The fungus, termed an endophyte, gives the plant greater insect resistance and increases tolerance to poor soils. The endophyte produces compounds which are toxic to the animal. Cattle consuming infected pastures decrease intake and gain. They are less heat tolerant, have rough hair coats, and may have hair loss or lameness Mares consuming infected pastures in the last trimester of gestation may have abortions, prolonged gestation, and decreased milk production Endophyte-free varieties of fescue were developed to address the problem; however, they are not as hardy and are expensive Infected seed can germinate in a noninfected field and start the transition to an infected field. Other varieties of fescue were developed that contain an endophyte that confers hardiness but does not have toxic effects. These are referred to as "Endophyte friendly". An example is Max Q.

Two products derived from poultry

poultry by-product meal and hydrolyzed feather meal. Poultry by-product meal is produced from head, feet, undeveloped eggs and viscera. It contains 48-64% CP that is of lower quality than flesh. Hydrolyzed feather meal is cooked with steam to break bonds in keratin.

Processing food for human consumption results in

production of co-products that are used in animal feeds. Co-product feeds are concentrates and roughages other than the primary products from animal and plant processing. They are derived from many industries including meat packers, fish processors, milk processors, flour millers, brewers and distillers, oil seed crushers, corn millers, and grain processors. In general, these are not fit for human consumption. Many of these co-products are concentrates and are included in the category of energy feeds or protein supplements.

The wet milling process for corn

removes the seed coat, bran, oil and starch. The brewery and distillery processes remove the starch during fermentation. Again, because the amount of protein in the seed doesn't change following extraction of the starch, the concentration of protein in the residue increases

Brewery or distillery products, brewers grains and distillers grains

respectively are relatively high in fiber and approximately 28% CP. Barley is predominantly used for brewing and both rye and corn for distilling.

Nitrate toxicity

results from excess nitrate intake due to excess nitrate accumulation in plants. caused by excess N fertilization and drought Use of swine lagoon effluent to irrigate bermudagrass pastures has resulted in this condition. Nitrate is normally converted to amino acids during plant metabolism; however, this process is decreased with excess N or drought. Ruminants are most susceptible because their site of fermentation is at the beginning of the GI tract. Nitrate is converted to nitrite and absorbed into body. It is nitrite that is toxic because it converts hemoglobin to methemoglobin which cannot transport oxygen. Microbes in the rumen do the conversion. This also takes place in the cecum and colon but to a lesser extent. Symptoms include increased respiration, trembling, convulsions, and death

Structure of Seed

see photo The main parts of the seed are the seed coat and bran layer, the endosperm, and the germ or embryo. The seed coat forms the outer protective layer of the seed and is higher in fiber content than other parts of the seed. The endosperm provides nourishment for the developing embryo. It contains starch and protein. The germ is rich in protein, oil, and phosphorus.

what kind of climate is NC

temperate climate. Cool season grasses that are pasture forages in NC include fescue, orchardgrass, timothy, and ryegrass. Warm season grasses include bermudagrass and switchgrass.

Energy Feeds

they are higher in energy density and lower in fiber than forages and roughages. Relative to fiber content they are defined as having less than 18% crude fiber or less than 35% cell wall. They are highly digestible. Types of feedstuffs in this category are: Cereal Grains Co-products from the milling industry Molasses Fats and oils Roots and tubers Beet and citrus pulps Whey products Seeds of other plants Fruits and nuts - not that common for livestock

Grasses and Legumes

two major forage families Grasses have long narrow leaves on a cylindrical stem Legumes often have 3 leaflets per stem They have a symbiotic relationship with bacteria in nodules in the root system (Figure 5). The rhizobia bacteria can use atmospheric nitrogen by reducing it to ammonia which the plant can use to synthesize amino acids. As a result, legumes do not need N fertilization and increase soil nitrogen content. Common examples are clover and alfalfa.