Section 3: Basic Beef Cattle Nutrition (Rae) Flashcards
3 phases of beef cattle production
1) cow-calf
2) stocker-grower
3) feedlot (finishing)
weaning age of calves
7-9 mo.
describe cow-calf phase
- generation of new product (calves)
- minimal resource inputs
- cows maintained on less-tillable land
- grass farming using “harvesting machines” (cows) **
- calves raised to weaning
describe stocker-grower phase
- calves purchased and fed high forage ration
- minimal resource inputs
- growing phase
- grass harvesting or small grain gleaning **
growing phase age of calves
8-15 mo.
describe finishing phase
- production of finished product
- intensive confinement op.
- fed mixed concentrate ration **
- commodities feeding **
- abundant, high energy feeds
- a short, intensive period
how many days until calves reach market weight?
90-150 days
cows with BCS of 8 or 9 usually…
didn’t calve for the last 1-2 years and have been fed too much nutrition
T or F: cows gain weight up until they give birth
T
why is it important to have good nutrition esp. in later gestation?
bigger calves, greater calf survival, less calf dz, greater calf weaning weight, cows get pregnant sooner after calving, GAIN significant weight during last 30 days of pregnancy
body condition scoring is:
a visual evaluation of nutritional status (1 to 9).
most cows are BCS:
3 to 7. 5 = ideal
one change in BCS correlates to how much weight change in beef cattle?
~75 lb.
normal gestational period of cow
285 days
normal calving interval
365 days (time from one calf to the next)
cows are bred how long after giving birth?
40 days
cows with BCS of ___ have the greatest chance of getting pregnant
6 (93% will get pregnant)
lighter weight calves bring less/more money per pound
more. However, in the end they bring less money per calf!
Methods/goals of increasing resource utilization efficiency in cow-calf grass farming
- select appropriate cow, pasture types
- max. efficient forage utilization
- min. purchased feed
Animal factors
- live weight
- physiological state (gestation vs. lactation)
- genotype
- age or proportion of mature body size
- health
Pasture factors
- herbage available (quantity)
- herbage edibility (intake, quality, concentration)
- toxins (exogenous and endogenous)
exogenous toxins come from:
fungus/bacteria
endogenous toxins come from:
chemical toxins
Environmental factors
- environmental temp/humidity/radiation
- wind/rainfall
Nutrient requirements of the cow and environmental carrying capacity of resources must be in:
harmony
When do cows have highest nutrient demand?
Period 1: post-calving, 80d
when do cows have moderate nutrient demand?
Period 2: pregnant and lactating, 125d
Period 4: pre-calving, 50d
When do cows have lowest nutrient demand?
Period 3: mid-gestation, 110d
dairy cows produce about __% more milk than beef cattle
10
calving in Florida usually occurs around what month?
January. This is also when quality and quantity of forage are most limiting
Quantity limiting of forage occurs between what periods?
4 and 2
important macro nutrients
Ca, P
important micro nutrients
Cu,Co,Se,Mg,Mn,Zn
important vitamins
A,D,E
carrying capacity (aka forage availability)
the estimated maximum stocking rate that can be grazed with a specific # of cows (AU) for a specified time w/o damage to the vegetation or a related resource. AU/acre of pasture
harvested forages are converted to:
AUM. AUM = acres x (tons/acre) x (AUM/ton)
on normal bahia grass florida pasture, there is adequate feed between which months out of the year?
june - october
goal of forage-based nutrition
attain a year-round forage supply despite variable quantities and qualities of forage supplies and environmental conditions
T or F: legumes are limited in Florida
T
table slide 35
:)
How to make regular bahia grass pasture provide almost year-round nutrition
1) fertilize to allow bahia to be ready earlier in the season (around Mar)
2) plant clover which is ready in Feb
3) plant ryegrass, which is ready in late Jan.
4) plant limpgrass which is ready nov/dec.
Now only have early january w/o grass, which you can harvest and feed hay
Why better to have more cows at a lower weight, than fewer big cows?
- produce more calves
- less wear/tear on facilities
- weight-related dosing
- higher calf weaning weight, but fewer calves
- cost goes up with larger cows
- need more energy to maintain them
variables for choosing the optimum cow
- cow size
- age
- milk production
- environment
effect of milk production on net energy requirement of 1000 lb. cow
increasing milk production requires more net energy
effect of cow size and milk production on net energy requirement
- more energy req. for heavier cows and higher producing cows
- must maintain nutrition during lactation phase in order to maintain body condition
management strategies to maintain nutrition/increase production
- adjust stocking rate (insure adequate forage during the stocking rate limiting months)
- cull open and poor producing cows
- control parasites/diseases
- target calving season that fits forage, supplements, marketing plan, and management
- hard to do in Florida and still match what other states do, so most producers still tend to calve when there is a nutrient deficiency for them.
- group cattle by age/nutritional needs
- keep cows in good condition
clover is high in:
protein
management strategies to keep cattle in good condition:
- separate cows in thin condition and feed add. supplements to improve rebreeding
- provide higher quality forages or higher lvls of energy balanced with protein
