Measuring cow herd performance


South Dakota State University Extension

Fall is a great time of year to put pencil to paper and evaluate the overall productivity of your cow herd, as well as the individuals within it. Making the effort to measure the performance of the cows within a herd will allow a producer to cull as needed, evaluate genetics, and alter management practices as needed. This effort begins with good record keeping from calving to weaning (See Production Records for the Commercial Cow Herd) and while it may seem time consuming and tedious, the pay offs are well worth the effort. There are a plethora of different measurements of performance; the following is a list of indicators that will allow producers to effectively measure the performance of their commercial herd at weaning.
  • Calf Death Loss (%): A majority of calf death loss occurs within the first 24 hours of calf life. This will allow an evaluation of calf management.
(Total calves dead prior to weaning ÷ Total number of calves born) × 100
  • Pregnancy rate (%): Following pregnancy checking in the fall, determining the overall fertility of the cow herd is critical to evaluate a herd’s reproductive success. In addition, it is good to identify pregnancy rate by cow age group, this will allow a producer to pinpoint if there are problems in certain groups within the herd such as 2 year olds, or older cows.
(Total number of pregnant ÷ Total exposed for breeding) × 100
  • Percent calf crop weaned (%): Determines the percentage of the cow herd that weaned a marketable calf.
(Total # calves weaned ÷ Total females exposed for breeding) × 100
  • Pounds of calf weaned per cow exposed (lbs.): When marketing calves on a live weight basis, this becomes the ultimate measure of efficiency within a cow herd.
(Total lbs. of calf weaned from herd ÷ Total females exposed for breeding)
  • Percentage of maternal body weight weaned (%): Determination of the percentage of the cow’s body weight that was weaned. In order to be effective producers in the herd larger cows must wean heavier calves to cover the additional maintenance requirement costs.
(Weaning weight of calf ÷ Body weight of dam) × 100
  • Average daily gain (lbs.): Determines the weight gain of calves on a daily basis.
  • Weight per day of age: Equivalent to average daily gain.
  • Adjusted 205 day weights: This allows for a standardization of all cow and calf performance, removing the factor of age of dam and birth date. One thing producers should keep in mind is that adjusted weaning weights remove calving date from the equation. This is an important economic factor when determining the performance of a commercial cow.
Table 1: Adjustment factors for 205 day weights.
 
  • Culling rate (%): Keeping track of the percentage of productive females that are exiting the herd on an annual basis will help establish the amount of replacement heifers needed and give producers and determine if there are longevity issues within the herd.
(Total number of cows culled ÷ Total number cows in herd) × 100
  • Calving interval (days): In order to maximize the profitability of a cow herd, cows need to be producing a live marketable calf every 365 days. To track this performance requirement producers can determine the calving interval of cows.
(Previous calving date – current calving date)
Weaning is a great time to evaluate certain performance traits and management systems within a producer’s cow herd. While the list above is not all inclusive, it is a great place to start. When producers establish a record keeping system for their cow herd, and use it, there is no limit to the improvements that can be seen in overall performance and profitability.
Source: Kalyn Waters

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