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NOTES ON BEEF COW HERD NUTRITION

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					               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           Trailer
Hay DM disappearance
      Lb./cow/day                   26.8        26.4         28.4             30.6
Hay DM waste/cow/day                 1.6         0.9           4.2             3.5
DM intake/cow/day                   25.1        25.4         24.3             27.1
Waste %, dm basis                    6.1         3.5         14.6             11.4
DM intake, % cow body wt.           1.84        1.76         1.82             1.96
From Buskirk, et.al., 1999

				
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