Calving Season and Weaning Management

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Calving Season and Weaning Management

• Calving time
• Spring-reasons
• 1. Grasses and forages have their highest
• nutritive value in the spring, and therefore most
• animals in the wild have their young in the
  spring
• 2. Weather more conducive to survival of calves
• 3. Minimum housing needs
• 4. More economical to feed dry in winter
• 5. Tradition in U.S.

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Calving Season and Weaning Management

• Calving time
• Fall-reasons
• 1. Calves weaned in spring when feeder
• prices are generally more favorable
• 2. More steady supply of feeders if also
• calving in the spring
• Regardless of calving season chosen, one should
  strive to calve within a 40 to 60 period-
  reasons
• 1. More uniform calf crop resulting

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Calving Season and Weaning Management

• Creep feeding
• Advantages
• 1. Increases weaning weights by about 50 lb.
• 2. Eases the stress on 2, 3 and 4 year old cows
• 3. Eases the stress on drought-shortened and
  over populated pasture
• 4. Lowers the stress on calves at weaning and
  makes adaptation to feedlot diets easier
• 5. Fall born calves maintained in drylot
  substitute creep feed for lack of pasture
• 6. Prepares calves for early weaning program

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Calving Season and Weaning Management

• Creep feeding
• Disadvantages
• 1. Calves may lose some condition if going into
• backgrounding program following weaning
• 2. Requires extra labor, equipment, feed and
• management
• 3. Not easily adapted to large pastures or range
• conditions

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Calving Season and Weaning Management

• Creep feeds
• Can start as early as about 6 weeks of age
• Many producers start at 3-4 mo. of age (
• July 1 when grass is short) 10-11 salt of
• total creep DM will limit intake to about 2.5 lb.
• daily DM intake
• Consideration
• 1.
• 2.
• 3.

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Calving Season and Weaning Management

• Creep feed examples
• All oats may or may not be processed
• Cracked corn 62.5 lb
• Oats 37.5 lb
• a.
• b.
• c.
• d.

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Calving Season and Weaning Management

• Implanting
• May improve weaning weight
• If implant at birth, may need to reimplant 70
• to 100 days later to get full benefit of 50 lb.
• weight increase

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Calving Season and Weaning Management

• Implanting
• Concerns
• 1. Steer and heifer calves implanted during
  nursing period, may not respond as well to
  implants during feeding period research
  contradictory on this

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Calving Season and Weaning Management

• Implanting
• Concerns
• 2. Reproduction
• a. Bulls implanted as calves suffer at least 50
• reduction in testicular size and similar
  reduction in
• futility
• b. Recent research by Montana and Kansas
• workers has shown no detrimental effects on
  fertility
• 1.) Previous research has shown lowered
• conception rates and incidences of fertility
• c. Conclusion do not implant nursing calves
  that
• are potential breeding stock

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Calving Season and Weaning Management

• Early weaning
• Considered to be any weaning age younger
• than 6 to 7 months
• Situations promoting early weaning
• 2 and 3 yr. old cows
• Cows with twins
• Drought conditions or insufficient pasture
• Fall calving
• to accelerate rebreeding in late calving cows

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Calving Season and Weaning Management

• Early weaning
• ISU study
• Crossbred cows 42 day. breeding season
• Spring calving late March through early May
• Fall calving late August through early October

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Postpartum Estrus Distribution
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Effect of Season and Age of Calf at Weaning on
Reproductive Performance of Cows
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Death Loss of Calves through 365 Days of Age
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Effect of Season and Weaning on Calf Performance