Here is the situation. Preweaned calves in the hutches seem to be taking longer than usual to get started on grain. The farm manager and calf raisers see this as a problem.
Questions to ask? First, let’s document when calves are beginning to regularly consume calf starter grain. Start calves out right away with a clean grain pail. Put in just 1 handful of grain. Dump and replace the grain daily.
With the procedure described above it is easy to see when calves begin to regularly “clean up” their grain. However, complicating the situation will be the fact that there is almost always a lot of variation among calves. So, we have to estimate when most of calves are regularly eating starter grain.
Let us suppose that last year we estimate that calves were averaging about 10 days to regularly clean up their “handful” of grain. By careful observation for a few weeks this year we conclude that now this same stage of consumption is reached about 19 – 21 days. Clearly, that is longer than last year’s estimated time during the same season of the year.
Second, we need to ask about the milk/milk replacer feeding program. What volume of milk is fed at each feeding, and how many feedings per day?
How much total volume of milk/milk replacer are the calves consuming each day? Most studies show that higher levels of milk feeding are associated with longer intervals until calves reach regular grain intake.
Generally, when we feed minimal amounts of milk (2 quarts twice daily) regular grain intake begins around 7 to 10 days for most of the calves. At 3 quarts twice-daily feeding rates about 5 days are added before regular intake happens. That makes the range when regular grain intake begins between 12 to 15 days. Nineteen to 22 days is a common starting time for calves drinking 4 quarts of milk twice daily.
Thus, it would be great to know if any change took place in the milk/milk replacer feeding program on this farm. They were feeding pasteurized milk both years.
There are no written feeding records estimating last year’s milk feeding program. Recalling what happened then is risky business if one wants reliable information. My records show that the protocol for last year was to start calves at 2 quarts AM and PM. Around 10 to 14 days they were increased to gradually to 3 quarts twice daily. That is where they stayed until weaning started. I do not have any data on protocol compliance.
I was told that this past winter season calves have been moved up more quickly. They were offered 4 quarts twice daily as soon as they would drink that much. Many calves, not all, reached that level by 2 weeks of age. When calves were regularly drinking this volume they were fed “more.”
I am guessing that some three-week old calves were drinking 3 gallons of whole pasteurized milk daily. I concluded, therefore, that the milk feeding rate almost certainly has gone up. I was curious why this happened. By asking around I discovered that for a variety of reasons the supply of waste milk to be pasteurized is greater this year than last.
On one hand, it is not a given that an increased supply of milk translates directly to an increase in the amount of milk fed to calves. It is possible that regardless of the supply the same amount was fed both last year and this. On the other hand, when we are dumping a lot of milk down the drain at the end of each feeding it certainly is tempting to feed on the “heavy” side.
Regardless of why more milk was fed, we know that at this year’s rate of milk feeding calf starter grain intake is almost certain to be delayed substantially compared to calves receiving 1 gallon a day.
Further inquiry showed that this year all the calves were reported to be eating 3 to 4 pounds of grain a day consistently around 6 weeks of age. At this age this farm drops the afternoon milk feeding; the calves have to get by on “only” 1.5 gallons of whole milk in the morning feeding for a week or so before all milk feeding is stopped. During the eighth week while the calves are in the hutches on a water and grain ration they average around 5 to 6 quarts of grain daily. As you might guess, how rigidly this weaning schedule is followed depends somewhat on the demand for hutch space.
At this point I asked everyone, “What is the problem? The calves have been eating grain regularly for about a month before milk feeding is stopped. They are consuming plenty of grain before they are moved to group pens. Body condition is good both before and after moving.” The answer was, “It just seems like they should start eating grain sooner.” My reply was, “If that is important to you, decrease your milk feeding rate.” As you may guess, this will not be settled in one conversation.