Ration balancing checklist for cattle

601

Source: Manitoba Agriculture, Food and Rural Initiatives

The protein (CP) and energy (TDN – total digestible nutrients) that an average beef cow needs:

  • Mid pregnancy: 7% CP and 55% TDN
  • Late pregnancy: 9% CP and 60% TDN
  • After calving: 11 to 12% CP and 65% TDN

Checklist

  • Target forage DMI (dry matter intake) of 2.5% BW (body weight) for cows. Increased DMI of 2.7 to 2.8% BW is possible under cold (-30°C) conditions with poor forage. For every 10°C decrease in temperature below -20°C, feed should be increased by 15% or an extra 6 ½ lbs of hay or 4 ½ lbs of grain per day.
  • Feed wastage with round bale feeders is 15%. If there is forage on the ground, it is 15% waste.
  • Maintain a rising plane of nutrition three to four weeks prior to calving. This is important for adequate milk production, return to estrus and high conception rates.
  • Adequate energy (TDN) can be monitored by assessing body condition score (BCS). Low TDN ration will result in loss of BCS.
  • Mineral supplements at 0.1 lbs per day prepartum and 0.15 lbs per day postpartum. 1:1 for legume based rations and 2:1 for greenfeed/grain/straw based rations.
  • Sodium (Na) levels of 0.1% will result in decreased consumption of salt and salt based mineral.
  • The calcium to phosphorus ratio (Ca:P) should be between 2:1 and 7:1.
  • The tetany ratio is potassium (K) divided by magnesium (Mg) plus calcium (Ca). The K/Mg+Ca ratio should not exceed 3.0:1 High potassium forage (over 2%) and/or low calcium forage (under 0.6%) and low magnesium forage (under 0.3%) can impact animal performance.
  • Adequate feed supplies can be estimated by rule of seven. The combination of tonnes of silage, bales of hay and bales of straw need to add to seven.
  • Assume light barley has a TDN analysis of 75% (regular barley had 83% TDN).
  • Formula to adjust TDN in forage with an unexpectedly low TDN analysis is TDN = 88.9 – (0.779 x ADF).
  • For Cowbytes ration program, set temperature to -15°C current and previous month, 1.3 cm hair depth, 10 KMH wind speed, ADG = 0.25 lbs, slaughter weight 200 lbs higher than cow weight and calf birth weight of 95 lbs.

Ration Balancing Checklist for Calves

The protein (CP) and energy (TDN – total digestible nutrients) that an average beef calf needs:

  • 550 to 800 lbs: 14% CP
  • 800 to 1050 lbs: 12% CP
  • 1050 lbs to finish: 10% CP
  • 1.5 ADG: 63 to 66% TDN
  • 2.0 ADG: 66 to 71% TDN
  • 2.5 ADG: 73 to 78% TDN
  • 3.0 ADG: 78 to 83% TDN

Checklist

  • Target forage DMI (dry matter intake) of 2.5 to 3.0% BW (body weight) for calves.
  • Rancher Rule 1: calves on a 60% roughage and 40% grain ration will have a 2.5 ADG.
  • Rancher Rule 2: feeders on a 85% grain and 15% roughage ration will have a 3.0 ADG.
  • Feed wheat can be used up to 40% of the ration; however it is typically used at 20%.
  • Limit corn silage to 60 to 65% of the ration on a dry matter intake basis for calves with the remainder comprised for alfalfa/grass hay and grain.
  • Mineral supplements at 0.1 lbs per day.  1:1 for legume based rations and 2:1 for greenfeed/grain/straw based rations.
  • Sodium (Na) levels of 0.1% will result in decreased consumption of salt and salt based mineral.
  • The calcium to phosphorus ratio (Ca:P) should be between 2:1 and 7:1.
  • The tetany ratio is potassium (K) divided by magnesium (Mg) plus calcium (Ca). The K/Mg+Ca ratio should not exceed 3.0:1 High potassium forage (over 2%) and/or low calcium forage (under 0.6%) and low magnesium forage (under 0.3%) can impact animal performance.
  • Adequate feed supplies can be estimated for background calves – three tonnes of silage or one tonne of dry hay for a 90 feeding period.
  • Assume light barley has a TDN analysis of 75% (regular barley had 83% TDN).
  • Formula to adjust TDN in forage with an unexpectedly low TDN analysis is TDN = 88.9 – (0.779 x ADF).
  • For Cowbytes ration program, set temperature to -15°C current and previous month, 1.3 cm hair depth, 15 KMH wind speed, ADG = 1.5 lbs or greater, slaughter weight 1350 lbs.

LEAVE A REPLY

Please enter your comment!
Please enter your name here