Intro to Animal Science chapters 5-7 study questions

Define carnivore, omnivore, and herbivore.

A carnivore is an animal that only eats meat. An omnivore is an animal that eats both plants and animals. An herbivore is an animal that only eats plants.

Describe how a feeding trial, a digestion trial, and metabolism trial differ.

A feeding trial is used to determine if an animal will eat a certain feedstuff and how they will perform on it. A digestion trial is used to discover which feedstuff is digested and absorbed by an animal. A metabolism trial is a more advanced version of a digestion trial that can include measure of certain things like urine and hair loss.

What is the difference between macrominerals and microminerals?

A macromineral is a mineral available in large quantities, and a micromineral is a mineral available in small quantities.

What are the overall body functions for which an animal uses nutrients?

An animal uses nutrients for maintenance, production, and reproduction. The amount of nutrients an animal uses depends on what type of species it is and the quality and quantity of products they are producing, if they are producing any.

What is the definition of an energy feed? What is the definition of a protein feed? Explain the difference between an energy feed and a protein feed.

An energy feed contains less than 18% crude fiber or less than 35% cell wall and have a protein content of less than 20%. They are usually high in starch and NFE. A protein feed contains more than 20% crude protein. Protein feeds have similar energy content as energy feeds, but their amounts of crude protein and crude fiber are what differentiate them.

What does bile do? Where does it come from?

Bile is one of the three alkaline secretions of chyme. Chyme is the name given to the material consisting of food, saliva, and gastric secretions. It is formed and concentration from the liver and is stored in the gallbladder until it is needed for digestion. Not all species store bile in the gallbladder.

Why do different animals use very different kinds of feeds?

Different animals use very different kinds of feeds because they have different types of digestive systems that are designed to digest different types of feeds.

Define digestion and describe the three major methods.

Digestion is defined as the breakdown of food by the digestive system in preparation for absorption. The three major methods of digestion are through the physical or mechanical actions of chewing (mastication) and muscular action of the digestive tract (peristalsis), the chemical action of hydrochloric acid, and the action of enzymes.

Describe eructation and discuss the consequences if a ruminant is unable to eructate.

Eructation is the removal of gas from the rumen through the esophagus. If a ruminant is unable to eructate, this gas will go into the trachea and lungs.

How do feeding trials help to generate feeding standards for animals?

Feeding trials help to generate feeding standards for animals by telling people if animals will eat a certain feedstuff and how they will perform on it. Some popular feed trials are growth trials, lactation trials, egg production, endurance, and certain measurements of specified body functions.

Define mastication. How do different animals accomplish this?

Mastication is another way of saying "chewing." Carnivores chew their food enough to reduce the size of their meat to swallow it. Herbivores need through mastication of their feed to allow bacterial enzymes access to the cellulose. Ruminants first form a bolus and then swallow it without much chewing. They later regurgitate the feed and chew it.

List the major similarities and differences in vitamin supplements and mineral supplements.

Mineral and vitamin supplements are similar because they are needed by animals in smaller amounts. The amount an animal receives depends on the feed ration they are on. Examples of mineral supplements are salt, bone meal, oyster shell, calcium carbonate, and limestone. Examples of vitamin supplements are ensiled yeast, liver meal, fish oil, and wheat germ oil.

For what purposes are nonnutritive additives added to rations?

Nonnutritive additives are added to rations to rations to stimulate growth or other types of production, improve feed efficiency, enhance health, or alter metabolism. Examples of nonnutritive additives are antibiotics, coloring agents, flavors, hormones, and medicants.

Define the science of nutrition and explain why one might choose to study it.

Nutrition is defined as the study of how the body uses nutrients to sustain life and for productive purposes. One might choose to study nutrition because it is necessary to understand in commercial livestock production. To feed an animal is 45-75% of the total cost of livestock production. Successful livestock producers have found ways to feed their animals that both provide them with the proper nutrition they need along with them being cost-efficient.

What is prehension?

Prehension is defined as the act of seizing and grasping.

What nutrients are measured by proximate analysis? What are the limitations of each individual test?

Proximate analysis measures dry matter, ash, crude protein, and ether extract. Dry matter is determined by heating a sample of feed until all the water is evaporated out of it. Ash is measured by burning off all of the organic matter in a feed sample. Crude protein is measured by the Kjeldahl process, which isolates and measures the amount of nitrogen in a feed sample. Ethel extract is determined by extracting it with diethyl extract.

What are the components and the functions of saliva, and what do you think dictates the amount of saliva that various species produce and how does it help the animal?

Saliva is composed of water and protein mucin. The functions of saliva are to lubricate the food so that the animal can chew and swallow it, stimulate the taste nerves, cleanse the mouth, buffer acids, provide nutrients for rumen microorganisms, maintain the proper PH for microorganisms, and prevent ruminal bloat. I think that the amount of saliva that various species produce is dictated what digestive system they have and whether they are carnivores, herbivores, or omnivores. Dogs and other carnivores rely on bicarbonates in saliva to buffer the acids produced by microorganisms. Ruminants rely on the antifrothing property of saliva to prevent ruminal bloat from occurring every day.

Describe the disciplines of nutrition, including the areas of specialty for nutritionists. Explain the differences between basic and applied nutritionists.

Since animal nutrition is a broad area of study, nutritionists specialize their areas of study into two categories: monogastric and ruminant. Monogastric animals are those animals with only one stomach, whereas ruminant animals are animals with a stomach divided into four compartments and have a rumen. Basic nutritionists study the metabolism of animals, whereas applied nutritionists focus their studies on cost-effective ways to feed animals that are raised for production.

Why was the Van Soest fiber determination method developed? What advantages does it offer over proximate analysis?

The Van Soest fiber determination method was developed to describe forages better in response to the limitations of proximate analysis. This method is able to predict the intake and digestibility of feedstuffs and evaluate heat damages to forages.

State clearly the advantages of the ruminant digestive system.

The advantages of the ruminant digestive system are that microbial fermentation is able to digest feedstuffs that the animal's enzymatic digestion process cannot, which increases the value of feed options that are cheaper. A ruminant is able to absorb vitamins, minerals, fatty acids, and amino acids better.

Explain the difference between a forage and a roughage. What are the characteristics of a good-quality forage?

The difference between a forage and a roughage is that a forage is considered to be a better quality than a roughage. The characteristics of a good-quality forage are being relatively immature when harvested by animals or mechanical means; being green and leafy; having soft, pliable stems; being free from mold or mustiness; being palatable; and being free from foreign material.

What are the disadvantages of the ruminant digestive system?

The disadvantages of the ruminant digestive system are that the fermentation process in the reticulo-rumen can destroy essential nutrients and decreasing the overall quality of their diet. The fermentation process also uses a lot of energy that is lost as heat and gaseous products of incomplete bacterial metabolism.

What are the eight categories of feedstuffs as recognized by the NRC?

The eight categories of feedstuffs as recognized by the NRC are (1) dry forages and roughages; (2) pasture, range plants, and green forages; (3) silages; (4) energy feeds; (5) protein supplements; (6) mineral supplements; (7) vitamin supplements; and (8) nonnutritive additives.

List the essential amino acids. Are there any additional amino acids for poultry? Are there any deviations from this list?

The essential amino acids are methionine, arginine, threomine, tryptophan, valine, histidine, isoleucine, leucine, lysine, and phenylalanine. There are two amino acids for poultry: glycine and proline. If available, arachiodonic acid is synthesized from linoleic acid. This is only essential if linoleic acid is absent or short in supply.

What is the function of the large intestine? What do bacteria do in the gut of a monogastric herbivore?

The function of the large intestine is to absorb water, electrolytes, vitamins, minerals, and volatile fatty acids. Bacteria in the gut of a monogastric herbivore produce some vitamins and important gases such as carbon dioxide and methane.

What are the differences and similarities of protein supplements from the three major sources of protein supplements?

The main similarity of protein supplements from the three major sources is that they are all generally expensive. Protein supplements from plant origins are high in crude protein and energy with a high protein content. Most of these protein supplements are from oilseed meals. Protein supplements from animal origins consist of meat, bone meal, blood meal, feather meal, dried milk, and fish meal. Milk products are the highest quality and the most expensive. Protein supplements from NPN are a cheaper option that is only used in ruminants. These are used with urea and other similar products.

What is the major anatomical difference in ruminants and nonruminants?

The major anatomical difference in ruminants and nonruminants is that the ruminant has a complex stomach with a system of digestion that is very different from that of a nonruminant.

List the nutrient categories. Why isn't energy a nutrient? Is it required for life?

The nutrient categories are water, carbohydrates, vitamins, minerals, proteins, and fats (lipids). Energy is not a nutrient because it is not required for an animal to maintain its current body weight and condition. Animals that are used for production, work, or growth purposes will require more energy than animals who only need enough nutrients to breath and have a heartbeat.

What are three portions of the small intestine, and what is the function of each?

The portions of the small intestine are the duodenum, jejunum, and ileum. The duodenum is the first part of the small intestine that is around a foot long. Excluding microbial fermentation, it is the main site of food breakdown in the entire digestive system. The jejunum is where the absorption of digestive end products takes place, and is the second longest part of the small intestine. The ilium is the last section of the small intestine. Its main job is to act as a connection to the large intestine, but absorption can also occur here as well.

What is the reticular groove and what does it do?

The reticular grove contracts and forms a tube that acts as a bypass of the rumen and reticulum and empties into the abomasum. It keeps milk out of a calf's undeveloped rumen.

What is the function of the reticulum? The omasum? The abomasum?

The reticulum is also a site of microbial action and acts as a pacemaker for rumen contractions. The heavier particles settle in the reticulum and pass through the omasum and abomasum while the lighter particles float on top of the rumen. The reticulum also catches foreign objects that a ruminant might have ingested that could cause hardware disease. The omasum absorbs water, electrolytes and VFA's and reduce the particle size of feed before it enters the abomasum. The abomasum is equivalent to the true glandular stomach in monogastrics and has the same functions.

What is the role of the stomach in digestion?

The role of the stomach is digestion is to physically break down food by the churning action created by the contractions of the muscles. It mixes the food with chemicals and enzymes. Hydrochloric acid is used to provide an acidic PH level in the stomach to allow gastric enzymes to work and kill bacteria. Lastly, the stomach is also used as food storage, which allows the animal to eat at a much faster rate.

What is the function of the rumen?

The rumen acts as a site of anaerobic bacterial fermentation. The bacteria in it digest carbohydrates along with other plant materials and produce volatile fatty acids. It is also a place where food is stored. A ruminant is able to eat fairly quickly and fill their rumen so they can hide to chew their food again from predators.

Describe the anatomy of the ruminant tract. What are the common names of the four ruminant digestive compartments found between the esophagus and small intestine?

The ruminant tract is composed of a stomach split into four different sections: the rumen, reticulum, omasum, and abomasum. After moving through the stomach, the feed contents move through the small intestine, cecum, and large intestine.

What are the similarities and differences in the first three categories of feedstuffs described in this chapter?

The similarities between the first three categories of feedstuffs described are that they are all referred to as roughages or forages. The feeds in these categories provide the bulk of the diets to herbivorous species. The differences between them is that it is extremely common to divide these roughages and forages into grasses and legumes.

What are the stomach types in livestock?

The stomach types in livestock are monogastrics and ruminants.

What are the three general types of analytical methods used to evaluate feedstuffs? Briefly define each method.

The three types of analytical methods used to evaluate feedstuffs are chemical procedures, biological procedures, and microbiological procedures. Chemical procedures are defined as standard chemistry applied to feeds. Biological procedures use animals to test feeds. Microbiological procedures use bacteria in place of animals to test feed.

What are the unique features of a horse's stomach?

The unique features of a horse's stomach are that the upper jaw is wider than the lower jaw, only allowing it to chew on one side of its mouth at a time. The horse also has a much smaller stomach than other livestock species the same size as it. It also does not have a gallbladder because it has evolved as a continuous eater and has no need to store food as bile. The large intestine accounts for over 60% of the total gut capacity and is equal to about 3/5 the size of the large intestine capacity of a ruminant that is the same size.

Why are VFA's of importance to the ruminant, and what does the animal do with them?

VFA's are important to the ruminant because they provide around 50-70% of a ruminant's energy requirement. These are absorbed through the rumen by the animal.