We all know that chocolate is bad for dogs, but what about cows? With Easter approaching we thought we’d discuss the ins and outs of chocolate toxicity.
Chocolate contains a chemical called theobromine (as well as a little caffeine). Humans metabolise theobromine and caffeine quickly, but dogs (and cats) take a lot longer to eliminate these chemicals from their body and so are more sensitive to developing toxicity. Cocoa powder and dark chocolate contain the highest concentrations of theobromine (15–20mg/g) while milk chocolate contains much less (2mg/g).
What are the signs of chocolate toxicity?
Clinical signs of chocolate toxicity in dogs include agitation, hyperactivity, drinking a lot of water, drooling, vomiting and diarrhoea. More serious signs include an irregular and racing heartbeat, muscle tremors, twitching and seizures and – in the worst-case scenario – death. The greater the dose (or the smaller the dog) the worse the signs will be, and they can last for days. Obviously, if you know your dog or cat has eaten chocolate you need to visit the vet ASAP.
What about chocolate in cows?
Chocolate toxicity is rarely cited as a problem in bovines – in fact, as you can see in this article some dairy farms use chocolate as part of their cows’ ration. Waste chocolate can be combined with other ingredients into a mixed ration that is balanced to supply the energy, fibre and protein that a cow and its rumen microbes need. Using waste chocolate and other human feed stuffs, such as bakery goods and lollies, keeps them from going into landfill.
However, there has been some reports of negative effects of chocolate in cows and calves:
- In dairy cows, a reduction in milk yield occurred when they were fed theobromine at approximately 15mg/kg body weight per day.
- A case of suspected chocolate toxicity occurred in a group of three to five-month-old calves fed a diet containing 5–10% waste chocolate for some weeks (an estimated theobromine dose of 45–90mg/kg body weight per day). The calves showed hyperexcitability, sweating and increased respiration and heart rates. They recovered when the chocolate was withdrawn.
Using the information above we can do some rough Easter maths. To consume enough theobromine to make them sick:
- A 100kg calf would need to eat 500g of dark chocolate or 3kg of milk chocolate.
- A 250kg heifer would need to eat 1kg of dark chocolate and 8kg of milk chocolate.
- A 500kg cow would need to eat 2kg of dark chocolate and 17kg of milk chocolate (500g of dark chocolate or 4kg of milk chocolate could cause reduced milk yield).
The following diagrams might help put it into perspective: 5, 10 or 20 dark chocolate Lindt gold bunnies are enough to make a calf, heifer and cow sick respectively. But a cow would need to eat 170 milk chocolate Lindt bunnies to get the same theobromine dose!
One milk chocolate egg for your favourite cow or calf shouldn’t be a problem, or if you lose one or two in the paddock during an Easter egg hunt. But how about you save the chocolate for yourself and give them a handful of grass instead? 😊
And remember: no chocolate for the farm dog or chocolate milk for the dairy cat this Easter!