You may be wondering why I look happy and disgusted at the same, right beside a cow. And why does this cow have a porthole on her side? Let’s start with the beginning. In my project, I want to evaluate the nutritive quality of certain plants. My goal is to find how quality modifies selection of resource by the White-tailed deer. A characteristic of plant quality is digestibility: the proportion of the plant that is digested by the animal and is not directly rejected in the feces.
Deer have “multiple” stomachs. A large part of plant digestion is done by bacteria in the rumen, one of these stomachs. By reproducing this bacterial digestion, it’s possible to measure digestibility. The more a plant is digestible, the more it’s a good resource for deer.
To reproduce a digestibility experiment at home, you’ll need:
· Rumen juice (OK, I clearly don’t know the name of that in English !): the bacteria mix that can be found in the rumen
· Artificial rumen : a machine that shakes the liquid and keep the temperature at 390C
· A strong stomach, cause it stinks
There are a lot of difficulties with this manipulation. The rumen juice needs to be fresh, used as quickly as possible after being taken out of the cow. The bacteria will die when in contact with oxygen, so all manipulations need to be quick and efficient! It’s quite hard to obtain rumen juice, but my friend Michaël is a pro (you can read about this in French here) * http://www.chaireanticosti.ulaval.ca/fileadmin/documents/pdf/Capsules/Capsule_Chaire_Anticosti_3.pdf*. A relatively easier technique is to make friends with a research center who has cannulated cows. These cows are equipped with a cannula that allows access to the rumen, without pain for the animal. Here’s a great video in French about cannulated cow *http://cve.grics.qc.ca/en/1097/25737*.
Thanks to the Centre de recherche en sciences animales de Deschambault, I can compare the digestibility of my plants sample! There is difference between cow’s bacteria and deer’s, but it’s a good approximation. This subject is quite complex, please ask me questions about it !