BeefCowNutritionL3

• How does a spring-calving beef cow show flexibility?

  LW loses over winter, level of energy intake following calving, high intakes and speed of LW recovery during the spring/summer pasture flush
• LW loss over the winter up to 10% (March) LW up to 6 weeks before calving has no effect in calving.
• Cows should gain prior to calving to allows for greater flexibility in post- calving management.
• Whatʻs one method of avoiding metabolic disorders in managing cows?

  Cows should lose some LW over the autumn-early winter period
• Provided the cow has calved in good condition, the first 40 days following calving no live weight gain is necessary.
• After calving, about 40 days elapses before the calf can fully utilize the amount of milk the cow can produce.
• What can boost the milk production of a cow and improve for the calf

  Switching to a high plane of nutrition 40 days after calving, growth rate of the calf
• Whatʻs important to ensure the cows return to estrus in time if pre-calving nutrition was low and cows calved in less favorable condition?

  Post-calving LW gain
• High intakes during spring flush

  Cows with calves at foot can gain considerable amounts of LW (up to 1 kg/day)
• Cows should be within 5% of their autumn LW at the start of mating for satisfactory reconception (CS 6-7).
• What can under-nutrition influence?

  Cow and calf mortality, calf BW/weaning weights, time for resume estrous activity, conception rates, metabolic disorders
• What happens if cow fails to quickly resume estrous in order to the young?

  Sacrifices next estrous cycle
• If a cow fails to quickly resume estrous all the way till Jan/Feb what happens?

  Lighter calves weaning
• How can you reduce dystocia?

  By controlling BW
• How can you control birthweight?

  By controlling nutrition, damʻs pelvic size, bull breed selection (EBVs), select bulls with shorter gestation length, select on calving ease
• Cow condition at calving is most important for conception rates because?

  Need energy reserves for lactation and reproduction
• How much can be depressed at calf weaning weights if thereʻs is poor nutrition before and after calving?

  5-10%
• How can cows buffer against poor feeding?

  Use her own body reserves if she has any
• While suckling, how much should a calf gain?

  1 kg/day
• When does a calf start eating grass?

  After 3 weeks of age
• After 12 weeks of age 50% intake may be grass.
• At 6 mos of age calves are still consuming up to 25-35% of total intake as milk.
• Time of Weaning


  Managerial decision based on calf's fate and pasture supplies
• With poor nutrition beef cows will progressively

  Utilize a high proportion of available pasture, utilize body reserves and lose weight, delay onset of estrus/fail to get pregnant
• Liveweight Problem Areas


  Winter LW loss continues up to calving, low LW after calving and at mating , max LW achieved too late in season
• What do thin cows conditioning look like?

  Sharp with bones protruding
• What do fat cows conditioning look like?

  Smooth and square with hidden bone structure
• Method of Scoring


  Evaluating fat cover on spine and tail head for body condition
• Thin Condition


  BCS 1-2: Emaciated with prominent ribs and tailhead
• Borderline Condition


  BCS 2.5: Ribs less obvious, some fat cover over spine
• Good Condition


  BCS 3-4: Moderate fat cover, fleshy appearance
• Fat Condition


  BCS 4.5-5: Overconditioned with large fat deposits
• The 5 times when to Condition Score:

  Weaning time, 30-45 days after weaning, 60-90 days prior to calving, calving, mating
• Hypomagnesemia


  Nutritional disorder due to low blood magnesium levels in livestock
• When is hypomagnesemia commonly seen?

  Pregnant and lactating cows in late winter and spring
• What are the predisposing factors of hypomagnesemia?


  Young spring herbage, stress, parturition and lactation, cow age and parity, abrupt change of diet, genetics
• Control options for Hypomagnesemia

  Defined mating period to control feeding, feed consistently over late autumn-winter to avoid sudden diet changes, blood tests after summer autumn diet or during feed shortage
• Top Dressing


  Applying nutrients directly to pasture for livestock consumption
• Whatʻs the ideal CS for beef cows at calving?

  5
• Whatʻs the average post-partum anestrous interval in adult beef cows?

  60 days