Sometimes called “inside-outside calves”, this is an uncommon birth defect seen in calves, lambs, piglets and probably kid goats. In these feti the abdomen and chest cavities fail to close leaving all the internal organs exposed. In addition the spine is arched like the calf was doing an extreme version of the limbo dance. Other developmental abnormalities may be present as well. In the calf pictured below, there are several abnormally angled limbs and the upper jaw is not symmetrical. These calves are dead at or shortly after birth.
When assisting a cow to deliver these calves, it can be difficult to identify them with certainty because the anatomy is so deranged. This may seem like it should make them easy to indentify but there are times when sorting out an abnormal position os a calf with normal anatomy surrounded by foetal membranes can be difficult to distinguish from a schistosomus.
Usually, either a fetotomy or a caesaren section is required in order to deliver these type of calves.
The cause(s) of this developmental defect have not been determined. They are usually solitary cases. they are the result of an accident that occurs very early in the development of the embryo. All of the internal organs are usually present, function normally, and these calves live just fine inside the cow’s uterus. Once they have to live in the outside world their bodies cannot function and they die.