NOTES ON BEEF COW HERD NUTRITION
1. Body condition scores (BCS) range from 1 [thin] to 9 [obese], with a range
of 4 to 6 being ideal. Each BCS change is about 75 lbs. of weight change
on a mature beef cow.
2. Nutrient needs during the lactation and breeding period are much greater
than during the dry period.
3. Peak lactation occurs 60 to 90 days after calving and this should occur
when forage quality and availability is greatest.
4. Feed costs are approximately 50% of the total costs of producing a
weaned calf.
5. It is wise to sort cattle into separate management groups in order to match
feed resources with cattle requirements. For example:
a. Weaned heifer calves
b. Bred heifers
c. Coming two year olds and thin cows.
d. Mature cows
e. Dry cows versus lactating cows.
f. Herd sires.
6. Daily dry matter intake of a cow is related to forage quality and her stage
of production. When expressed as a % of cow body weight, expected
daily dry matter intakes will be:
a. Low quality forages (dry grass, straw, etc.)
i. Dry cow
1.5%
ii. Lactating cow
2.0%
b. Average quality forages (native, brome or orchard grasses)
i. Dry cow
2.0%
ii. Lactating cow
2.3%
c. High quality forages (alfalfa, silage or green pastures)
i. Dry cow
2.5%
ii. Lactating cow
2.7%
7. Weather changes including wind chill can dramatically alter a cow’s daily
nutrient requirements.
8. Mineral supplementation is usually provided free choice to brood cows
and normal consumption is about 3 lbs. to 5 lbs. per cow per month. Both
macro and micro minerals must be supplied.
a. Forages tend to be relatively good sources of calcium, while grains
tend to be high in phosphorous.
b. Soils influence trace mineral content of plants. Michigan soils tend
to be deficient in cobalt, iodine, selenium and marginal in copper.
9. Dry matter losses of harvested forages depends upon length of storage
time, storage method and feeding method. See tables 1, 2 and 3 on the
reverse side of this handout. It will be necessary to harvest, store and
feed greater amounts of forages to compensate for these losses.
Table 1. Percent dry matter loss of round hay bales
Storage Method
Storage Period
Up to 9 months
12 to 18 months
Exposed
Ground
5 – 20
15 – 50
Elevated
3 – 15
12 – 35
Covered
Ground
5 – 10
10 – 15
Elevated
2– 4
5 – 10
Under roof
2- 5
3 – 10
Enclosed barn
Less than 2
2- 5
From Huhnke, 1993
The lower value in each range represents well formed bales in low rainfall areas
(>25 in./yr.) The higher values are for areas with higher rainfall (<40 in./yr.) and
relatively high humidity.
Table 2. Effect of storage system on d.m. loss of ryegrass hay stored 7 mo.
Source of Loss
Storage System
Storage
Animal Refusal
Total
Ground
28
22
50
Gravel
31
17
48
Tires
35
6
41
Rack
26
6
32
Rack with cover
12
2
14
Barn
2
1
3
From Redmon, 1996
Table 3. Dry matter loss of large round hay bales due to transporting and feeding
Range
Average
Transporting hay
1–5
3
Feeding method
Hay ring
1 – 20
10
No hay ring
5 – 45
20
Rolled out
5 – 25
15
Adapted from Wheaton, 1980; Anderson and Mader, 1985
Table 4. Effect of feeder type on intake and waste of round-baled hay
Round Bale Feeder Type
Ring
Cone
Cradle
Hay DM disappearance
Lb./cow/day
26.8
26.4
28.4
Hay DM waste/cow/day
1.6
0.9
4.2
DM intake/cow/day
25.1
25.4
24.3
Waste %, dm basis
6.1
3.5
14.6
DM intake, % cow body wt.
1.84
1.76
1.82
From Buskirk, et.al., 1999
Trailer
30.6
3.5
27.1
11.4
1.96