Download AGR 300 Mid-Term Exam Questions and Answers: Animal Nutrition and Digestion and more Exams Veterinary in PDF only on Docsity!
AGR 300 MID-TERM EXAM QUESTIONS WITH ACCURATE
SOLUTIONS
True or False: Domesticated animals consume a wider variety of foods than wild animals. -- Answer โโ False True or False: Nonessential nutrients can be synthesized by an animal's body. -- Answer โโ True A nutrient that is needed in relatively large amounts in the diet is a(n) ______________. -- Answer โโ Macronutrient Which of the following is NOT a function of the digestive tract?
- Convert chemical energy into mechanical energy
- Break food into smaller pieces using mechanical action
- Absorb nutrients through passive diffusion
- Absorb nutrients through active transport
- Excrete wastes
- Transport food using peristalsis
- All of the above are functions of the digestive tract -- Answer โโ 1. Convert chemical energy into mechanical energy Match the following species of ruminants with their feeding classification. Goats Sheep Deer Cattle -- Answer โโ Intermediate Feeders
Intermediate Feeders Concentrate Selectors Roughage/Grass Grazers Which of the following is NOT a function of mastication (chewing) in carnivores?
- increase surface area
- reduce particle size
- allow enzymes to act on food molecules
- All of the above are functions of chewing in carnivores
- None of the above are functions of chewing in carnivores -- Answer โโ 1. increase surface area True or False: Ruminants may chew a particle of feed up to 50,000 times a day. -- Answer โโ True True or False: Ruminant animals have a highly developed set of upper incisors. -- Answer โโ False Match the types of teeth below with their function. Molars Canines Incisors -- Answer โโ Grinding and crushing Tearing Ripping and/or nipping Match the following jaw muscles with their purpose. Masseter & Medial Pterygoid Lateral Pterygoid Temporalis Muscle -- Answer โโ Force for general crushing and grinding.
- Kill Bacteria
- Produce Hormones
- Control release of food into the small intestine
- All of the above are functions of gastric digestion
- None of the above are functions of gastric digestion -- Answer โโ 5. All of the above are functions of gastric digestion Match the digestive actions below with the stomach secretions that cause them. Clotting of milk Hydrolyzing protein Denaturing protein Decrease stomach pH -- Answer โโ Rennin Pepsinogen HCI HCI Which of the following gastrointestinal hormones does NOT originate in the Duodenum?
- Gastrin
- Secretin
- Cholecystokinin
- Gastric Inhibitory Protein
- All of the above originate in the duodenum
- None of the above originate in the duodenum -- Answer โโ 1. Gastrin Development of rumen papilla is spurred by what two fatty acids? -- Answer โโ Butyric & Propionic Acid What two gasses are primarily produced and belched out during the rumination process? -- Answer โโ Carbon Dioxide & Methane
What Volatile Fatty Acid (VFA) is most prevalent in the rumen? -- Answer โโ Acetate Which of the following can occur when a ruminant animal suffers rumen acidosis?
- Laminitis
- Decreased Milk Production
- Reduced availability of protein
- Reduced Availability of energy
- All of the Above
- None of the Above -- Answer โโ 5. All of the Above True or False: Most mineral absorption occurs in the rumen. -- Answer โโ False Which of the following is NOT a region of the abomasum?
- Anterior
- Cardiac
- Fundic
- Pyloric
- All of the above are regions of the abomasum -- Answer โโ 1. Anterior Which of the following organs serves as the primary absorption site for most nutrients?
- Rumen
- Large Intestine
- Pancreas
- Small Intestine
- None of the Above -- Answer โโ 4. Small Intestine True or False: Absorption in the small intestine occurs relatively quickly. -- Answer โโ True Nutrients can be absorbed by which of the following mechanisms?
protein fats oils -- Answer โโ Minerals Which of the following is NOT a role of the large intestine? fermentation absorption of water storage of digesta secrete enzymes all of the above are functions of the LI none of the above are functions of the LI -- Answer โโ Secrete enzymes True or False: An animal's ability to digest milk decreases with age. -- Answer โโ True In your own words, describe the digestive differences between pre-gastric fermenters and post-gastric fermenters. Include examples of each as well as advantages and disadvantages. -- Answer โโ Pre-gastric fermenters have a large fermentation compartment between their esophagus and their "true" stomach. Ruminants are pre- gastric fermenters and their rumen is where digestion and fermentation occur. This gives them an advantage compared to post-gastric fermenters because they can make better use of alternative nutrients, detoxify some poisonous compounds, and have more effective use of fermentation end-products. There are also some disadvantages though, such as that their fermentation is inefficient and they are susceptible to toxins produced by rumen microbes. Although pre-gastric fermenters have a slower digestive process, they are more efficient per unit volume of food. Examples of pre-gastric fermenters include ruminants such as cattle, sheep, and deer, as well as non-ruminants such as hamsters, kangaroos, and hippos. In post-gastric fermenters, digestion occurs in the large intestine and the colon. There are two types of post gastric fermenters; cecal fermenters and colonic fermenters. Examples of cecal fermenters include the rabbit, rat, and mouse, while examples of
colonic fermenters include the elephant, horse, cat, and dog. Advantages of post-gastric fermenters include being able to spend less time eating and having a faster digestive process. Since they have this faster digestive time though, they are unable to utilize their food as efficiently as pre-gastric fermenters. The organ that shunts milk directly to the omasum in young ruminant animals is called the _________________. -- Answer โโ Reticular Groove The 1 is the largest stomach compartment in adult ruminant animals, while the 2 is the largest stomach compartment in newborn ruminant animals. -- Answer โโ 1. Rumen
- Abomasum True or False: The gut function of a newborn ruminant animal is similar to that of an adult monogastric animal. -- Answer โโ True List three things that contribute to the development of a newborn's rumen. -- Answer โโ 1. Exposure to the environment and other animals.
- Consumption of solid feed.
- Consumption of water. Which of the following is a characteristic of Rumen By-pass? Rumen By-pass allows for more efficient use of protein Rumen By-pass eliminates energy loss from methane Rumen By-pass reduces energy loss from heat Rumen By-pass reduces ammonia loss All of the above are true about Rumen By-pass None of the above are true about Rumen By-pass -- Answer โโ All of the above are true about Rumen By-pass
True or False: A ruminant can survive indefinitely without a functional rumen as long as it is not fed roughages. -- Answer โโ False Match the four steps of rumination with their definitions
- Regurgitation
- Remastication
- Reinsalvation
- Redeglutition -- Answer โโ 1. Using reverse peristalsis to return food to the mouth.
- Rechewing the food bolus in the mouth.
- Adding more saliva to the food bolus.
- Re-swallowing the food bolus and liquids. Ruminant animals spend about a third of their day eating and a third of their day ruminating. -- Answer โโ True Unlike the act of vomiting, regurgitation is a controlled and deliberate process. In your own words, explain the process (steps) of regurgitation -- Answer โโ Regurgitation is the first step of rumination for ruminant animals. Food is sent straight to the rumen where some digestion will begin. Regurgitation is stimulated when the digesta scratches against the fiber mat near the cardiac sphincter, which then stimulates the reticulum to contract. This contraction of the reticulum pushes the digesta to the cardia. The animal will then inhale with it's epiglottis closed which creates a vacuum. Next, the cardiac sphincter will open and the esophagus will dilate. The negative pressure caused by this vacuum forces the digesta into the esophagus. Finally, rapid reverse peristalsis moves the digesta back into the animal's mouth, allowing for remastication, reinsalivation, and redeglutition. What are the two most prevalent gasses in the rumen? -- Answer โโ Carbon Dioxide & Methane
Microbes provide all of the following benefits to the ruminant EXCEPT: Provide high quality protein Produce volatile fatty acids (VFA's) Digest cellulose and hemicellulose Detoxify some toxic compounds Microbes provide all of the above benefits -- Answer โโ Microbes provide all of the above benefits The primary source of energy produced in the rumen is in the form of ________________. -- Answer โโ Volatile Fatty Acids (VFA) Microbes reap little or no benefit from their relationship with ruminant animals. -- Answer โโ False The most prevalent type of rumen microbes are _____________. -- Answer โโ Bacteria Summarize feeding strategies that can maximize microbial growth in the rumen. -- Answer โโ Maximizing an animal's dry matter intake and offering food to the animal at all times will help maximize microbial growth in the rumen. Carbohydrates and protein fractions should be balanced at the same time, since bacteria require both for amino acid synthesis. Also, no rapid changes in ration will help. Which of the following is NOT a source of carbohydrates. Sugars Minerals Cellulose Starch -- Answer โโ Minerals Match the carbohydrate classifications below with their description.
True or False: Ruminants can break down lignin as long as they are provided plenty of water. -- Answer โโ False What are two reasons a producer might want to feed indigestible fiber (soluble or insoluble) to a monogastric animal (non-horse). -- Answer โโ Fructooligosaccharides are indigestible by animals but are often used as prebiotics. They can promote the growth of lactic-acid bacteria and suppress the growth of E. coli. True or False: Most feed carbohydrates are monosaccharides. -- Answer โโ False Which of the following sugars can be absorbed into the body? Monosaccharides Disaccharides Oligosaccharides Polysaccharides All of the Above None of the Above -- Answer โโ Monosaccharides Match the disaccharides on the left with their monosaccharide components on the right. Lactose Sucrose Maltose -- Answer โโ Glucose & Galactose Glucose & Fructose Glucose & Glucose In your own words, describe the differences in carbohydrate digestion and absorption between ruminant and non-ruminant animals. -- Answer โโ Non-ruminant animals begin carbohydrate digestion in their mouth with salivary amylase, which ruminants do not have. Digestive enzymes in the small intestine of non-ruminants break down
carbohydrates into monosaccharides, mostly in the form of glucose. These monosaccharides are taken up by either active transport, used for glucose and galactose, or facilitated transport for fructose, and carried to the liver. Ruminants do not use digestive enzymes like non-ruminants do, instead they use their rumen where almost all carbohydrates are fermented. While non-ruminants get most of their energy from glucose, ruminants use volatile fatty acids. Glucose in non-ruminants and volatile fatty acids in ruminants are then absorbed into the animal's blood circulation. In ruminant animals, most carbohydrates are fermented in the _________________. -- Answer โโ Rumen Cellulolytic bacteria are predominate in animals fed 1 diets, while amylolytic bacteria are predominate in animals fed 2 diets. -- Answer โโ 1. Roughage / Forage
- Grain / Concentrate True or False: Cellulose takes longer to ferment than simple sugars. -- Answer โโ True True or False: As rumen pH decreases, cellulolytic bacteria become more active. -- Answer โโ False One glucose molecule can be fermented into one of three volatile fatty acids (VFA) with varying degrees of efficiency. Match the VFA on the left with the by-products (waste) that come along with its formation. Acetic Acid Propionic Acid Butyric Acid -- Answer โโ Carbon Dioxide, Methane, and Heat Water Carbon Dioxide & Methane
