Final Review Flashcards
1
Q
Volume of Rumen
A
- 50 gallons
2
Q
VFAs
A
- produced by microbes in rumen
- acetic, propionic, and butyric acid
3
Q
Methane Formation
A
- H2 + CO2 produced by microbes = CH4
- released thru eructation, otherwise rumen pH would decrease
4
Q
Peak Dairy Cattle Lactation
A
- day 60
- after which, lactation decreases
5
Q
Lactation, Body Weight, and Feed Intake Curve for Dairy Cattle
A
- dry matter intake increases with increase in lactation
- body weight decreases at beginning of lactation and slowly increases (has another growing calf inside her during late lactation period)
6
Q
Feed for Dairy Cattle
A
- 50% roughage, 50% concentrates
- comes from byproducts of plant production
- 20% of plant material produced in CA are given to cows (high quality nutrition)
- part of the reason why CA has so many dairy cattle
7
Q
Total Mixed Ration (TMR) for Dairy Cattle
A
- formulated diets for dairies
- depends on feed access
- differs throughout the year
- made up by nutritionist
- rare to have whole herd on same diet
8
Q
Roughage
A
- primary feed for dairy cattle
- bulky feed
- low digestibility
- high crude fiber
- low energy
- variable protein content
- store through hay and silage
9
Q
Alfalfa
A
- high in protein because of rhizobium symbiosis (nitrogen fixers –> proteins)
- very expensive
- needs lots of water
- can be made into dried hay that doesn’t rot because of low moisture content
10
Q
Silage
A
- whole plant cut into pieces, tractor drives over each layer to remove air and limit aerobic microbes
- white tarp weighed down over silage
- 4 days later, aerobic microbes have consumed all the oxygen and are replaced by lactic acid forming microbes
- lactic acid produced decreases pH of silage from 7 to 4, making conditions bad for other microbes to grow
11
Q
1 Silage in CA
A
- corn silage
12
Q
Dairy Feeding Ration
A
- 1/2 is stored in hay or silage
13
Q
Energy Concentrates
A
- cereal grains, molasses, fats/oils
- high digestibility
- low crude fiber
- moderate protein
- high energy
14
Q
Protein Concentrates
A
- animal: blood, bone, fish meal; dry milk powder
- plant: soybean/canola/cottonseed meal, sunflower/cottonseed, dried distillers grains
15
Q
Dried Distillers Grains (DDG)
A
- most often fed
- byproduct of ethanol produced for fuel by corn
- solids from ethanol become DDG
16
Q
Corn in US Destination
A
- majority to fuel
- 5-10% of gasoline is ethanol, which comes from corn
- 40% of corn produced goes to fuel
- 5% of corn produced goes to cattle
17
Q
Lipids
A
- seeds, byproducts, supplements
- energy dense (9 kcal/g compared to 4 kcal/g for carbs and proteins)
- can’t exceed 6% of dairy diet
18
Q
Dairy Cattle Vitamins
A
- need fat-soluble vitamins thru diet
- A, D, E, K
- don’t need Vitamin B from diet
19
Q
Minerals
A
- 21 essential
- macro: need large intake of
- micro: small intake
- mineral deficiencies in soil supplemented by salt licks
20
Q
Water
A
- clean, fresh, available, convenient
- one water space (2 ft of tank perimeter) for every 15-20 cows
- 2+ watering locations for larger groups
21
Q
Starter Feed For Calves
A
- high in energy
- 15-18% crude protein
- hay, hay + grain, all grain + protein pellet
22
Q
Dairy Heifers
A
- good to high quality roughage
- breed at 14-15 mo
- 1st calf at 2 yo
23
Q
How to/why accustom heifers and cows to lactating diet?
A
- add concentrates to diet in last 2-3 weeks pre-calving (5-8 lbs per cow per day)
- need to adjust microbial population to fresh cow
- reduce ketosis incidence
24
Q
Springers
A
- heifers w/in 2-3 mo of calving
25
Ca in Diet of Dairy Cows
- reduce Ca in feed so that cow mobilizes Ca from her own body reserves after giving birth to fulfill high Ca demands
- reduction of Ca in cow diet before calving reduces milk fever
26
Body Condition Score of Lactating Cows
- at lactation start: 3.75
- lose 1 BCS that must be restored prior to next lactation
- loss of BCS due to loss of fat
- avoid energy intake deficiency
27
