Precision feeding does not only apply to the lactating cows. Heifers make up a large portion of the animal numbers on the farm as well as their feed costs. Using the cash flow numbers summarized by the Extension Dairy Team, the combined feed costs (includes home raised and all purchased feeds) for heifers and dry cows made up anywhere from 18 to 27% of the total feed costs per cow. This is still a substantial part of the budget and why controlling feed costs for heifers is important. Sometimes the focus is mainly on the best nutrition for the pre-weaned calf and then short cuts are taken from the post weaned heifers through freshening. Age at first breeding and age at first calving are typically the two key time points for monitoring animals. Unfortunately problems detected at breeding age are too late to correct in a timely or economic manner.
There are a couple of scenarios that play out on a dairy operation with heifers. If forage quality is excellent and high in energy content, heifers can become fat and not meet the height requirement for their age. This can affect heifers becoming pregnant and also having calving difficulties. If forage quality is extremely high in protein content and energy limited, heifers may have the height but not enough body condition. If forage quality is poor and protein and energy are not properly supplemented, then heifers may not be at the correct weight or height when they reach breeding age.
There are tools available to monitor heifer weight over time. If scales are not available, then weigh tapes can be purchased to selectively measure animal growth over time. Ration adjustments can be made helping heifers get on the right track. Evaluating the big picture, forage inventory may need adjusted to produce the quality forage that is best suited to the heifer's requirements. It is a balancing act to keep energy level in check and to avoid excess protein feeding (from forages) that can be an environmental concern (ammonia emissions) as well.
Action plan for monitoring heifer growth
Goal: Using a weigh tape, measure heifer weights at 4, 8, and 12 months of age on at least 50% of the animals in a particular age group. Measure the weight on all heifers on day of calving. Record the information in the Penn State Customized Dairy Heifer Growth Chart.
Step 1: Purchase a heifer weight tape.
Step 2: Every two months, measure 50% of the animals in a particular pen averaging in age of 4, 8, and 12 months.
Step 3: Measure the weight on each heifer after calving.
Step 4: Record information into the Penn State growth chart spreadsheet comparing the farm's heifer weights with expected.
Step 5: Present the graph at profit team meetings to examine how well heifers are growing and if ration adjustments are needed.
Example body weight chart evaluating the farm's heifer body weight compared to the goals.
Monitoring an economic component is necessary to determine if a management strategy is working or not. For the lactating cows income over feed costs is a good way to check that feed costs are in line for the level of milk production. Starting with July's milk price, income over feed costs will be calculated using average intakes and production for the last six years from the Penn State dairy herd. The ration will contain 63% forage consisting of corn silage, haylage and hay. The concentrate portion will include corn grain, candy meal, sugar, canola meal, roasted soybeans, Optigen and a mineral vitamin mix. All market prices will be used.
Also included are the feed costs for dry cows, springing heifers, pregnant heifers and growing heifers. The rations reflect what has been fed to these animal groups at the Penn State dairy herd for the past 6 years. All market prices will be used.
Standardized IOFC starting July 2014
Note: January's Penn State milk price: $19.13/cwt; feed cost/cow: $6.63; average milk production: 85 lbs.
Standardized feed cost/non-lactating animal/day starting July 2014