Final Exam Flashcards
Choose the defining characteristic(s) of ruminants:
- herbivores
- ungulates
- pre gastric fermentation
The rumen is composed of 5 sacs. Which one is NOT considered a sac of the rumen?
- Cranial
- Ventral
- Ventral Blind
- Dorsal
- Dorsal Blind
- Reticulum
reticulum
Why should a prey species have a ruminant gastrointestinal tract?
- Ruminants can digest later on in a safe place
- Ruminant digestive systems allow for increased time in between meals
Volatile fatty acids are an end product of fermentation. What are the 3 most common VFA’s and their total number of carbons?
Acetate C2, Propionate C3, Butyrate C4
The __________ is the main site of pregastric fermentation, while the ___________ does this but also catches harmful objects. Most water absorption happens in the __________ which may also act as a pump regulating liquid passage. The ___________ is the site of gastric secretions. Absorbing nutrients within the stomach complex happens most efficiently in the _________ .
rumen, reticulum, omasum, abomasum, rumen
In the abomasum, cheif cells synthesize ____.
pepsin
Why is it important to know the evolution of the ruminant gastrointestinal tract?
The adaptation of the ruminant GI tract allows diverse species to thrive through symbiosis.
What does the microflora NOT contribute to the symbiosis relationship with a ruminant?
Controls the temperature
What is an example of a chemical property that influences digestion?
heat treatment
T or F: Dry matter intake and physical characteristics of feed influence residence time, while rate of fermentation is influenced by concentration of microbes and intrinsic traits of feed.
True
What type of grazing strategy do sheep exhibit?
intermediate feeder
What happens in the gastrointestinal tract of a browser?
Lower retention time
The prehensile action of cattle and goats differ. Generally, _______ are the least discriminate when choosing what to eat whereas _______ are the most discriminate because they use their lips and teeth to pick through plant parts easily.
cattle, goats
Why is it not always a good idea to put sheep and cattle together when interspecies grazing?
They compete for the same resources
Typically, cattle are harvested around 80% of physiological maturity. Which of the following might result in a shift of the ideal time of harvest from 80% of physiological maturity for cattle? Select all that apply.
- change in feed price
- change in value of the animal
Where is puberty defined on the composition of gain curve?
More than 50% of caloric intake contributes to adipose gain
Where do animals partition nutrients to before anything else?
maintenance
Why is it difficult to get dairy cows pregnant during lactation?
They partition nutrients toward lactation over reproduction
Which nutrients provide energy for the body to use? Select all that apply.
- carbohydrates
- protein
- lipids
The amount of energy to raise the temperature of 1 mL of water by 1 degree Celsius is a _________ .
calorie
What units of measure are most often used for energy among ruminant nutritionists when evaluating cattle diets?
Mcal
Having a positive retained energy means cattle have enough energy towards development, gain, or lactation. What does it mean when an animal is in a negative energy balance?
Expending more energy than they are getting from food
Immunity, Reproduction, Lactation, Muscle, etc. have a metabolic priority in the body. What happens in the bloodstream regarding delivery of nutrients?
Changes in nutrient flux depending on the metabolic priority
In the net energy system, there is _________ energy lost between gross energy and digestible energy. Net energy is differentiated from metabolizable energy due to _________ energy losses.
fecal, heat
What does TDN stand for?
Total digestible nutrients
What is the fatal flaw with the TDN calculation?
The assumption that protein and carbohydrates have the same amount of energy per gram
Animals metabolize protein to use for energy. What happens when an animal consumes more protein than it needs?
Energy is lost through urea
T or F: The energy in 1 kg of corn = the energy in 1 kg of alfalfa
False
Why is the TDN assumption of energy from protein an issue?
- It can depend on the animals need to metabolize protein for energy
- there is not always the same metabolic protein from animal to animal
- the amount of protein consumed is dynamic
- proteinis is always 1.2 calories per gram different from carbohydrates
- It can depend on the animals need to metabolize protein for energy
- there is not always the same metabolic protein from animal to animal
- the amount of protein consumed is dynamic
Energy is important when formulating cattle diets because we want to add pounds to an animal that will increase its value at market. How can we guess the final shrunk body weight of an animal we are feeding?
- using frame size
- using industry averages
- using the mother’s body weight at maturity
It is difficult to measure NEg in growing animals. Why is it much easier to measure energy used by a dairy cow?
energy can be directly measured through the milk
The types of glycosidic linkages between monosaccharides have major effects on energy and gain when metabolized in a growing animal. What type of glycosidic linkage does sucrose have?
alpha
Which is not a function of carbohydrates used by ruminants?
structural components of muscle fibers
T or F: Carbohydrates are required for the body each day to function.
False
Amylose, Amylopectin, and Glycogen are all forms of starch used by ruminants. What is the structural benefit of these molecules being branched? Select all that apply.
- Branched molecules have a greater amount of anomeric carbons to increase solubility in water
- Branching compacts the molecule requiring less space
In aerobic fermentation, oxygen acts as the final electron acceptor. What does not act as a final electron acceptor in anaerboic fermentation?
Ca+
Ruminant _________ can breakdown starch, cellulose, and hemicellulose into glucose or fructose. Glu and Fru go through __________ to form pyruvate. Pyruvate creates __________ from fermentation that can further be metabolized and used by the animal.
microbes, glycolysis, VFAs
Microbes are beneficial when an animal does not have the ability to digest a nutrient itself. What is a cost to the ruminant with the presence of microbes?
Microbes oxidize nutrients the animal could utilize on its own
VFAs are important because they are used for many functions throughout the body. Acetate is used for __________ synthesis. __________ is used in gluconeogenisis to form glucose. Epithelial fuel sources, like ____________ , are other types of energy that allow for glucose sparing by gastrointestinal tissues.
Lipid, Propionate, Butyrate
What are the benefits of altering the VFA profile to propionate? Select all that apply.
- increases circulating glucose
- decreases methane production
Feed processing increases rates of digestion and influences changes in VFA’s, like greater propionate digestion. Which is not a type of feed processing?
adding an essential oil
Ionophores, like monensin, are used in more than 90% of cattle diets. What is an effect of adding an ionophore to a ration?
increase propionate production
Buffers are used in cattle diets to control acidity of the rumen. Typically, a weak base is used. It dissociates and creates an ion in the rumen. The greater amount of ions create a ______________ environment that increases body water flow into the rumen. Essentially, flushing the ________ out of the rumen and diluting the ruminal liquid.
hydrophobic, acid
Lactic acidosis is caused when the pH decreases and lactogenic bacteria take over due to highly fermentable carbohydrates in the diet. What are signs of lactic acidosis? Select all that apply.
- diarrhea
- poor feed intake
- laminitis
- abscessed liver
T or F: Fiber is digested in the small intestine of ruminants.
False
Associative effects can be positive or negative depending on the concentrate:forage ratio and bacteria that participate in the fermentation of those feeds for energy. What is an example of a negative associate effect?
competition within the microflora of the rumen
Amino acids are all structured with an amine group, a carboxyl, and an R group. Which amino acids are used in protein production?
alpha
From the diet, proteins are used for many metabolic mechanisms. What is not a function of protein?
formation of triglycerides
The multiple stave hypothesis explains that ruminants can only synthesize as much protein according to the concentration of the limiting amino acid. What can we do to increase protein synthesis?
Increase the concentration of the limiting amino acid
Crude protein is a guess based off of the percent Nitrogen multiplied by a constant. Why do nutritionist use crude protein versus true protein? Select all that apply.
- it is hard to account for microbial crude protein
- nitrogen concentration is easily measurable
In ruminal fermentation of protein, there is a soluble fraction, a potentially fermentable fraction and a non-fermentable by microbes fraction. Which parts make up the equations for ruminally degradable protein and ruminally undegradable protein?
RDP = ___ + ___
RUP = ___ + ___
RDP = A + dB
RUP = C + uB
The rate of disappearance (Kd) of protein is influenced by what factors? Select all that apply.
- heat
- particle size
- rumen pH
The concept of asynchrony revolves around the animal rapidly fermenting carbohydrates, but not having enough protein available to the microbes. What is a consequence of this?
decreased fermentation
Why is it less common to see protein and carbohydrate synchrony?
the urea cycle keeps high amounts of protein cycling for 3-4 days
Why does the liver resynthesize urea from ammonia (NH3) and CO2?
NH3 is a charged molecule
How much metabolizable protein is provided to the ruminant from MCP?
64%
T or F: Amino acids fed to an animal are the same amino acids found in the product made from the animal.
False
Limiting amino acids prevent protein use by livestock. What can we do when feeding production animals to meet their different amino acid requirements?
use protein complementation
What are other ways to increase protein utilization in livestock, besides protein complementation? Select all that apply.
- synthetic amino acids
- ruminally protected amino acids
__________ AA are not synthesized in the body but are used for protein synthesis. ____________ AA are not synthesized in adequate amounts to support an important physiological process.
essential, functional
Which vitamin(s) can be synthesized in the rumen?
- vitamin K
- vitamin B
Is water hardness an issue in terms of palatability for ruminants?
no
Calcium should be supplied at ___ % DM from __________ in cattle rations.
1, limestone
What macro mineral is important to feeding DDGS?
sulfur
In green lush pastures spring cattle may develop grass tetany. Producers can provide high _____________ mineral to unlock alternative absorption pathways to alleviate mineral interactions in the spring forages.
magnesium
Ruminants lose water in many different ways. Which one has the greatest total body water loss (>50%)?
respiration
What factors influence water intake in ruminants?
- temperature
- lactation
- DMI
- availability
If cattle do not seem to be eating, what is the first thing a producer should consider?
checking the waterer
Water can be expressed as a function of body weight. On average, about how much water should cattle be consuming per day?
1 gal/100 lbs
Along the gastrointestinal tract, the epithelium consist of ____________ epithelium. These epithelium have ___________ meaning there is an apical and basolateral side.
columnar, directionally
What is this primary role of vitamins and trace minerals in the ruminant feeding industry?
Act as a vehicle whereby service fees are charged to producers
What is commonly used to protect against iodine deficiency?
iodized salt
Where are trace minerals typically stored?
tissue
What source of trace minerals is typically the cheapest?
inorganic
Animals do not require any nutrient as a percent. What is a reasonable estimate to establish a nutrient requirement?
dry matter intake
T or F: All warm-blooded mammals eat to a common energy endpoint when not limited by physical fill.
True
When the caloric density of the diet increases then total feed intake __________ and the energy intake _________ .
decreases, stays the same
What mechanism currently explains how cattle achieve satiety in short periods of time?
hepatic oxidation theory
Chemostatic regulation of intake relates to the hormones and nervous signaling that tell the brain to stop eating. What affects this? Select all that apply.
- rate of digestion
- caloric density of the diet
- soluble nutrients
Ruminants and nonruminants differ in the sense of metabolic fuels because nonruminants utilize ____________ while ruminants utilize propionate.
glucose
Feed intake increases propionate that then signals satiety through what reaction?
oxidation
The hormone leptin from __________ decreases appetite and decreases body weight. Ghrelin is another hormone from the _________ that increases appetite and increases body weight.
adipose, stomach
Why might an animal feel hungry if they have increased body fat when leptin is supposed to decrease appetite?
insulin has a negative feedback on leptin
The hepatic oxidation theory’s function on short-term feed intake is thought to function similarly in ruminants and non-ruminants. Why then does the difference in digestion of food in ruminants result in an increased importance when feeding highly fermentable diets? Select all that apply.
- rapid fermentation means more acid production
- high risk of acidosis
Are predictions of dry matter intake increased, decreased, or not affected by anabolic steroids?
increased by 6%
Propionate from rumen fermentation of CHO is used in which metabolic process to help in the formation of energy for the animal to use?
TCA Cycle
Dairy x Beef crosses entering the beef system is a great example of how DMI is affected by breed type because…
crosses eat 4% more than beef animals
What drives predictions of dry matter intake when one assumes no environmental or outside influences?
caloric content of the diet
The presence of mud _______ intake and ________ caloric expenditure.
decreases, increases
Which ionophore contributes to reductions in daily feed intake?
monensin
Digesta retention time is approximated from reactor volume and digesta flow rate, meaning feed value can differ between a larger cow and a smaller cow. Why is this?
Rumen volume is a function of body size
What are the end products of digestion of carbohydrates in the rumen?
VFA, MCP, CO2, CH4, H
In the digestion theory, which of these variables are (reaction rate, digesta retention time, concentration of reactants, reactor volume) positively related to digestion and which are negatively related to digestion?
- reaction rate
- concentration of reagents
- reactor volume
- digesta retention time
- reaction rate = positive
- concentration of reagents = negative
- reactor volume = negative
- digesta retention time = positive
What is the y-axis is this graph illustrating retention time?
rate of appearance
What does the letter “C” represent is this graph illustrating retention time?
K1, primary site of pooling
When estimating shrunk body weight, we use body weight x 0.96. Why do we leave 4% out of the estimation? Select all that apply.
- approximation of digesta in the GIT
- cattle lose mass from stress of a trailer
T or F: Breed, sex, and physiological state affect maintenance requirements.
true
What is the most accurate way to measure maintenance requirements of an animal?
Restrict feed and measure heat loss
What are the end products of digestion of lipids, protein, and nonstructural carbohydrates in the small intestine? Select all that apply.
- amino acids
- fatty acids
- monosaccharides
T or F: Surface area does not define heat lost from the body.
False
Why do we feed fiber to ruminants? Select all that apply.
- increase rumination
- decrease eating rate
- increase efficiency
- decrease cost of gain
When cows sort through feed, they do not receive all the nutrients they need. What can we do to help prevent sorting?
add water
Feeding silage to ruminants allows for many benefits to the cow and the producer. What is NOT a benefit to feeding silage?
Ensiling allows a place for aerobic bacteria to produce toxins
During silage fermentation, we want ________ as a product because it has ______ energy loss and ____ dry matter loss. This allows for a higher energy availability from the plant.
lactate, little, no
To get a proper ensiling, what particle size is best to produce the most lactic acid?
small particle size, easy to pack
T or F: To determine whole plant moisture content, one can look at the black line formed on the kernel of the corn plant.
False
Fasting heat production and Net energy for maintenance are equal because….
Energy cannot be created nor destroyed
What are some ways cattle can adapt during heat stress? Select all that apply.
- decrease feed intake
- sweat
- increase respiration rate
Cattle with a very low body condition score have a higher need to mobilize body fat to deal with stress. This can also be referred to as….
negative energy balance
Cattle are fed protein that exceed their requirements because ruminants lose protein in many ways. What are some examples of protein loss? Select all that apply.
- bacteria in the feces
- urine, hair, skin
