By Rodney Dennis, Ph.D., Dairy Nutritionist/Calf Specialist
Raising healthy, high-performing calves without digestive upsets, bloating and diarrhea requires attention to detail that includes providing the required amount of a properly mixed milk replacer.
A recent study conducted by the University of Wisconsin looked at the variation that can occur when mixing milk replacer on the farm. Two Wisconsin dairy farms were used in the study. One farm mixed several batches of milk replacer per feeding while the other mixed one batch for all calves for each feeding. Farm 1 used the cup provided in the milk replacer bag, mixed in a five-gallon bucket, and then fed in pails. Farm 2 mixed one batch per feeding in a mechanical mixer by weighing the milk replacer powder before it was mixed with water. The report did not indicate how the water was measured. Samples of prepared milk replacer were taken over a one-week period on each farm. A total of 85 samples were collected by volume and 75 samples by weight on Farm 1. For Farm 2, a total of 60 samples were collected by weight. The samples were analyzed to determine the total solids concentration. In addition, the mixing temperature was taken on 190 samples on both farms to determine the effect of temperature at mixing on solids content of the mixed milk replacer.
The results indicated the following:
- The variance in total solids concentration on samples taken by weight was greater (4.88%) than the variance on samples taken by volume (1.14%).
- The range in total solids concentration was greater on Farm 1 (11.4- 19.2%) with multiple mixings/feeding than on Farm 2 (12.6-16.2%) with a single-batch mix/feeding system.
- Mixing temperature also influenced the total solids concentration of the milk. The lower the temperature of the water at mixing, the greater the possibility of variation in total solids concentration of the mixed milk replacer.
This study indicates the potential for inconsistency in milk replacer mixing on farms. The study also shows the importance of water temperature at mixing and proper measuring of the milk replacer powder and water. Closely following the label mixing directions on all Kent milk replacers is of utmost importance for best performance of calves.