Ruminant Nutrition (Exam 2) Flashcards
45-60% of total cost of producing milk or beef is represented by _____ costs.
feed
Optimal nutrition leads to what 2 things in ruminants?
- better product quality
- healthier animal
What can nutrition predict about animals?
performance
What are the products of microbial fermentation?
volatile fatty acids
What percent of ruminant energy are made up of VFAs?
80%
3 main types of VFAs
- acetic acid
- propionic acid
- butyric acid
Give the percentage of the total volatile fatty acids that each type makes up:
- Acetic Acid
- Propionic Acid
- Butyric Acid
- 55-90%
- 10-45%
- 12-18%
Acetic Acid is used to build _____ in ruminants.
fat
Propionic Acid is used to build ______ in ruminants.
glucose
Butyric Acid is important for _______ and for _____ development in the rumen.
ketones
papillae
What are 3 management practices that affect ruminant nutrition?
- lying space
- bunk space
- available feed
Why is bunk space important in ruminants?
leads to less competition between young & old cows
Crude protein is found in ruminant diets and composed of ______ and _____.
protein + non-protein nitrogen (NPN)
Fat in a ruminants diet can be fed as ______ such as in grains and oil seed, or in _______ which are in forages.
triglycerides
glycolipids/phospholipids
Are proteins fully degraded by the rumen? Fats?
a fraction of protein intake is degraded, a fraction is not
In ruminant diets, fats that are (degradable/undegradable) by the rumen are preferable.
undegradable
What 3 problems can occur with an excess of degradable fats in the rumen?
- decreased fiber digestion
- decreased milk fat
- decreased income
Testing ____ levels can gauge the amount of protein in cattle and indicate if there is an issue with excess protein.
MUN (milk urea nitrogen)
4 compartments of the ruminant stomach
- reticulum
- rumen
- omasum
- abomasum
Function of the Reticulum
*rumination
prevent larger particles from continuing in GI tract
What occurs in the process of rumination by the reticulum?
anti-peristaltic contractions lead to regurgitation (“cud-chewing”)
Function of the Rumen
microbial digestion
use papillae for absorption
Function of the Omasum
acts as pump (transfers digesta from reticulum –> abomasum)
absorption
Function of the Abomasum
“true stomach”
enzyme secretion
What 3 things does the Omasum absorb?
water
VFAs
bicarbonate
3 purposes of rumination process
- rapidly ingest feed (can chew later)
- reduce particle size (microbes can use!)
- increase saliva production (8-10 hours per day)
In the rumen, what is the ideal pH? Temperature?
pH: 5.8 - 6.4
Temp: 100-108 F
What 3 microbe types are found in the rumen?
- bacteria
- protozoa
- fungi
What is the function of resident bacteria in the rumen?
digests fiber + starch
For bacteria in the rumen, the fiber digesters respond (slowly/quickly) to change while the starch digesters respond (slowly/quickly) to change.
slowly
quickly
What is the function of resident protozoa in the rumen?
digest bacteria for protein
What is the function of fungi in the rumen?
digest fiber (increase during high fiber diets)
Periparturient Hypocalcemia is also known as “_____” which means what?
milk fever
low calcium around birth
3 symptoms of Periparturient Hypocalcemia
down
wobbly
staggering
3 predispositions of Periparturient Hypocalcemia
- parity (how many times female has had offspring)
- breed
- nutrition
What hormone regulates Periparturient Hypocalcemia? Through what endocrine organ?
PTH via parathyroid gland
3 ways to prevent Periparturient Hypocalcemia
- nutrition
- DCAD
- calcium binders
What is the most important factor in preventing Periparturient Hypocalcemia?
DCAD (dietary cation anion difference)
How does DCAD prevent Periparturient Hypocalcemia?
adds a slightly acidotic diet which controls calcium levels
What is the most palatable DCAD that is used in diets to prevent Periparturient Hypocalcemia?
HCl
What are the 3 types of ketosis?
- Type I
- Type II (Fatty Liver)
- Type III (Butyric Acid)
Match the type of Ketosis to its characteristics:
- insulin resistant; during first 10 day of lactation
- improper fermentation of silage; feeding ketones to animal
- not eating enough to meet energy demands; 3-6 weeks into lactation
- Type II (Fatty Liver)
- Type III (Butyric Acid)
- Type I
Which type of ketosis needs to address the post-partum diet? Which type needs to address the pre-partum diet?
post-partum: Type I
pre-partum: Type II