Question: I live on a farm and we have 5 dogs( 2 jack Russell's and 3 working collies) what is the most common farm animal to be infected by the parasites carries by dogs and what is the most common parasite for dogs to transmit?

Marisol Collins answered on 10 Nov 2016:

Wow! Amazing! You are lucky to live on a farm, and to have such great dogs!
Thank you too for a great question. You have asked a very important research question, and something that a lot of scientists are working on. There are a number of parasites that dogs can transmit to farm animals, and I would say that it is sheep and cattle are the most commonly affected by them. I’ll give you a couple of examples of common ones:
Neospora is a tiny parasite of a type called protozoa, and it is transmitted by dogs in their poo to cattle when they eat grass contaminated with infected dog poo.. In cows it is a very serious cause of abortions, and can even affect an entire herd.
Another common protozoa parasite is sarcocystis, and this is passed from dogs to sheep. In both cases, dogs get the parasite by eating infected raw meat from sheep and cattle.
In many parts of the world, the parasite that I study, a tapeworm of dogs called Echinococcus, is very common. This is a tiny worm that again is passed to dogs when they eat infected raw sheep meat. A real worry with this parasite is that it can also cause serious disease in many other species, including humans.