Cows have 4 digestive department inside a cows stomach region. These digestive departments names are rumen, reticulum, omasum, abomasum.
1. The Rumen – this is the largest part and holds upto 50 gallons of partially digested food. This is where the ‘cud’ comes from. Good bacteria in the Rumen helps soften and digest the cows food and provides protein for the cow.
2. The Recticulum – this part of the stomach is called the ‘hardware’ stomach. This is because if the cow eats something it should not have like a peice of fencing, it lodges here in the Recticulum. However, the contractions of the reticulum can force the object into the peritoneal cavity where it initiates inflammation. Nails and screws can even peroferate the heart. The grass that has been eaten is also softened further in this stomach section and is formed into small wads of cud. Each cud returns to the cows mouth and is chewed 40 – 60 times and then swallowed properly.
3. The Omasum – this part of the stomach is a ‘filter’. It filters through all the food the cow eats. The cud is also pressed and broken down further.
4. The Abomasum – this part of the stomach is like a humans stomach and is connected to the intestines. Here, the food is finally digested by the cows stomach juices and essential nutrients that the cow needs are passed through the bloodstream. The rest is passed through to the intestines and produces a ‘cow pat’. Source 1