Check in with Zambezi and her 10-Month-Old Hippo Calf 

Hi Linda! Great question. I spoke to the keepers and they have this feedback (and a keeper named Grace says a special hello!) for you. Hippos are considered pseudo-ruminants by some. Many people argue that they are ruminants with just one less chamber in their stomach. But our keepers' opinion is that true ruminants have four chambers in their stomach: the rumen, reticulum, omasum, and abomasum. A hippo's three stomach chambers are also a little different from the four chambers listed, so they're different in quantity, but also in function. Hippos can digest fiber relatively well, but are not as effective digesters as cows - who are true ruminants. To our knowledge, hippos do not chew cud. Cows regurgitate food, re-masticate the food, re-swallow the food (the three Rs of rumination), whereas there does not seem to be any evidence of hippos engaging in this process. We feed our hippos around 30 pounds of hay a day and we do not see regurgitation, re-mastication or re-swallowing. All in all, the way we manage their GI system is essentially the way you would manage a true ruminant. Cetaceans have a three-chambered stomach similar to cows, but quite different from hippos, possibly nodding to a shared ancestor. Hippos have 36-40 teeth and most are used for chewing. Their molars are located in the back. They do not have a hard upper palate like a cow or a giraffe. The teeth in the front are for defense, consisting of incisor tusks and canine tusks. The rest are molars with the exception of milk-teeth, which are essentially leftover baby teeth occurring in between the tusks and the row of molars. These teeth are the reason for the discrepancy between 36 and 40 because some hippos retain all four milk teeth and some do not. Some of our adult hippos still have a couple of their milk teeth. They look like black dots about the size of a silver dollar just below the surface of the gum.

@@CheyenneMtnZoo Wow, thank you SO much for the info, from this old bio-science nerd! (And grateful for the howdy from Keeper Grace!) This is *fascinating*! I did not know cetaceans had multi-chambered stomachs, but now I am well on my way down that science info rabbit-hole. While I've kept horses for decades, I only started keeping sheep in the '00s, and only the the past 4 years have I had tame, friendly sheep who will settle down to visit with me while belching up a cud. I have yet to feel I understand multi-stomach digestion well enough to do excellent husbandry, but now I know the Three R's! Thank you for this informative reply! To quote Dug, the dog from the movie "Up", you are all "very good and smart"!

Biko and Kasai enjoy rotating through spaces, indoors and outdoors, but were out of the camera's view in this video.