Transcript Cattle Nutrition powerpoint

Cattle Nutrition
Ruminant Herbivores
Calf- young animal
Heifer- female calf that has not given birth
and is less than 30 months old
Cow- older than 30 months old, or has
given birth
Bull- intact male
Steer- castrated male up to 4 years old
Ox- castrated male, more than 4 years old
Dairy Cattle
Main objective- increase dry matter intake
to produce higher levels of milk
production
Key factors: energy, ration digestibility,
rumen fill, palatability, body weight( BCS),
environment, frequency of feeding and
water
Phase feeding program
Phase feeding
- Changing the nutrient concentration in a
series of diets formulated to meet an
animal’s nutrient requirements more
precisely at a particular stage of growth
or production
- Based on lactation and gestation cycle
Phase 1
First 10 weeks of lactation
 Peak milk production happens in this
phase
 Negative energy balance develops, so cow
uses body stores to make up difference (
can borrow fat, but cannot borrow
protein)

What to feed in Phase 1
Increased grain for energy ( corn, wheat,
soybeans)
 Protein supplementation to meet amino acid
requirements ( dried brewers grain, distillers
grain, corn gluten meal)
 Increased concentrates and fats to increase
energy density of feed ( soybeans, sunflower
seeds)
 Sodium bicarbonate “ buffer” to reduce
acidosis and maintain ruminal ph

Phase 2
Begins 10 weeks post calving and can
continue to 20th week
 Highest dry matter intake happens here
 Nutrient intake is finally in balance with
nutrient needs

What to feed in Phase 2
Lower protein levels because requirement
is met by supplementation in Phase 1
 Adequate fiber
 Limited grain intake
 Frequent feeding ( minimizes digestive
upset)

Phase 3
“late lactation period”, cow is pregnant
again
 Nutrient intake exceeds requirement for
production
 Main period for restoring body reserves
for next lactation

What to feed in Phase 2
Easiest phase to manage because cow is
pregnant and milk production is declining
 Increased amount of forage instead of
concentrates
 Lower protein

Phase 4
Most of the “ dry” period
 Final regaining of any lost body weight
happens here
 Goal is to get cow in good condition for
parturition, but not excessively fat ( BCS
of 3.5 out of 5.O scale)

What to feed in Phase 4
High protein, energy, Ca and P needs
 Combination of legume-grass hay and
corn silage ( with added vitamins and P0
 Long stem grass hay ( length of hay
matters)
 Limit grain to energy and protein needs

Body Condition Scoring
A numeric system to subjectively assess
and animal’s degree of fatness
Fat Cow Syndrome
- High blood lipids and fatty liver from
eating excess energy from grain or corn
silage
- Can lead to calving difficulties, displaced
abomassum and ketosis
Phase 5
Last 1-3 weeks of “dry” period, just
before calving
 Referred to as a “transition period”
 Increase grain intake to prepare rumen
for high energy diets that will be needed
postpartum

What to feed in Phase 5
Gradual increase in grains
 Small amounts of all ingredients used in
the lactation ration
 Maybe decrease Ca in “ milk fever” prone
cows

Beef Cattle Nutrition
Most critical factor influencing
performance of cattle on forage diet is
the amount of Dry Matter Intake
 Young, growing grass and pasture crops
usually have ample nutrients
 old pastures, crop residues and
harvesting methods cause reduction in
nutrients

Biological Cycle
Goal: optimal nutrition at each stage, not
maximum nutrition
Cycle is made up of 4 periods that
span 1 year: 3 trimesters and 1
postpartum period
First Trimester ( 95 days)
Begins the 1st day of conception
 Nutrient needs are for maintenance and
lactation if the cow has a calf with her
 Milk production is declining at this stage

Second Trimester ( 95 days)
Calf is weaned, lactation requirements
end
 Lowest nutrient requirements at this
point
 Feed minimally
 Easiest and most economical time to
increase a thin cows BCS

Third Trimester ( 95 days)
Rapid fetal growth causes rapidly
increasing nutrient needs
 Watch BCS carefully, cow gains 1 lb per
day
 Too thin cows experience dystocias, weak
calves and decreased milk production

Postpartum Period ( 80 days)
High lactation requirements
 Feed intake is 35-50% higher than nonlactating cow
 Nutritional stress at this point causes
problems during the cow’s next breeding
( usually 80 days post partum)

Energy Requirement
Energy is considered first in
balancing diet for beef cattle, it’s the
largest portion of the ration
 Energy utilization determines cow’s ability
to use other nutrients
 Good quality forage satisfies adult
energy requirements
 Poor quality forages need to be
supplemented with concentrates

Protein Requirements
50% of all protein and amino acid needs
are met by microbial protein synthesis
 Protein deficiency is common when cows
consume straw and low quality hay
 Urea is commonly used as a protein
supplement

Beef Cattle, Water requirements
Need abundant supply at once daily
 Range cows consume 2 ½ gallons daily in
winter and up to 12 gallons per head in
summer
 When salt is added, water need is
increased
 Fresh succulent feeds or silage help
reduce need

Beef Cattle mineral
requirements
Salt- need more when eating succulent
forages than when eating drier forage
 Calcium- depends of Ca concentration in
soil, higher needs in growing and lactating
cows
 Phosphorus- Low P levels in roughage, so
P is often offered free choice in a mineral
mix
 Cobalt- required for rumen
microorganisms to synthesize vitamin B

Minerals continued
Copper- Simental and Charlois have a
higher requirement than Angus
 Iodine- deficiencies in Northwest and
Great Lakes area soil; supply via iodized
salt

Beef Cattle Vitamin
Requirements
C, D, E, K and B complex- no need for
supplementation; ruminal microflora
synthesizes B complex and K,Vitamin C is
synthesized in tissues, Sun dried forages
contain lots of Vit D and E
 A- roughage and grains are low in Vit A,
causing a deficiency. Cattle on pasture can
store large amounts of Vit A for 2 months in
liver, so deficiency isn’t immediately apparent.
Look for signs of rough coat, diarrhea,
excessive lacrimation

Grazing Systems and
Management
1.
-
Continuous Grazing
Most common type of grazing scheme
Cow grazes 1 area for the entire season
up to 1 year
Low maintenance, but production suffers
Grazing systems continued
2. Deferred rotational grazing
- 4 pasture system
- 1 pasture would not be grazed from
spring to mid summer in order to allow
desirable plants to flower and reach seed
maturity
- The following year another pasture would
not be grazed
- After 4 years, all four pastures will have
had time to rest
Grazing systems continued
3. Rest rotation
- Uses 3-5 pastures
- 1 pasture is not grazed for an entire year,
while herd uses other pastures
Grazing Systems continued
4. Short duration grazing
- Developed in France
- 8-40 pastures grazed intensively for 2-3
days, then not grazed again for several
weeks
Nutritional Disorders
1.
-
-
Pasture bloat
Comes from consuming lush legumes (
alfalfa, red clover)
Relieve bloat by inserting stomach tube
into rumen and giving anti-foam material
( ex vegetable oil)
A trocar is used in extreme cases to
release pressure ( large “needle”
puncture through skin and gas rushes
out)
Nutritional disorders continued
Grass tetany
- Low Mg levels in blood from grazing lush
green grass pastures
- Common in cows nursing calves under 2
months
- Symptoms: excitability, cows act blind
- Fix by feeding free choice mineral
supplement containing Mg, early in grazing
season
Nitrite toxicity
- Caused when intake of nitrite is in excess
of the rumen’s ability to convert it to
ammonia
- Causes hemoglobin in blood to change
into a form which cannot transport
oxygen to the tissues
- Cow dies from asphyxiation
- Treat with injection of IV methylene blue
Fescue toxicity
- Caused by grazing or consuming
harvested hay from tall fescue pastures
- Cow eats the endophytic fungus that
grows between the fescue cells
- signs: soreness in hind limbs, “ fescue
foot” hooves and tail slough off,
hypersalivation and polyuria
Acute Pulmonary Emphysema “ Asthma’
- Occurs in western US when cattle are
moved from dry rangelands to lush meadow
pastures abruptly
- Signs seen in 4-5 days after diet change
- Symptoms: labored breathing, extended neck,
open mouth breathing, grunting
- Prevention: ( no treatment) slowly introduce
cattle to new pasture and supplement with
monensin