While I am not a veterinarian, I would rule out the low pH as we feed acidified colostrum to calves (pH of 4) with no problems once they get used to the acidic feed (adding a little sodium bicarb can neutralize the pH if necessary). The higher levels of sugar could cause scouring, not the quick death you report. I am not aware of the toxicity and relationships to candida (I assume this is a strain of bacteria). Perhaps one of our readers can assist.
The sucrose could be difficult to digest as the calf may not have the enzymes to degrade the sugar, but this may cause dehydration and scouring. Note that calves do not digest sucrose. Only rumen bacteria can digest sucrose in a bovine. Once the rumen is functional, the sugar is quickly degraded by the microbes, and a calf acquires digestive enzymes in two to three weeks after birth.
The candida is a yeast and probably not the cause of death. I would not recommend feeding chocolate milk largely due to the sucrose as mentioned by Dr. Hutjens. It is also likely that it has created conditions which enable other more harmful bacteria such as Clostridia to proliferate, which can result in the rapid death your calves experienced.
The percentage fat and protein in this product are lower than whole milk or most milk replacers.
As previouosly mentioned, I would not recommend chocolate as it contains a compound that can be toxic.
Mike Hutjens, Extension Dairy Specialist, University of Illinois - Illini DairyNET
Robert James, Extension Dairy Scientist, Virginia Tech
Arlyn Heinrichs, Dairy Extension, Penn State University
John Bernard, Dairy Extension, University of Georgia
