RICKETS 643 



in most cases that preceding the actual development of symptoms 

 of rickets there are certain disturbances of digestion. This often 

 takes the form of loss of appetite, the animals become weak, and 

 bloating of the belly may be a prominent symptom. As the disease 

 progresses the animal frequently develops an abnormal appetite, 

 showing a desire for dirt, gnawing on the sides of the pen, and 

 drinking manure water. This is simply an effort on the part of the 

 pig to secure those elements of food in which its diet is lacking. 



Some time before the deformity in the bones is noticeable the 

 animals suffer from severe pain and aching of the muscles, bones, 

 and joints. The pigs will walk with a stiff, lame gait, and lie down a 

 great deal. They will often rise only when forced to do so, and 

 then will squeal and grunt when made to move about. In some 

 cases the pain is so severe that the animals are unable to rise or use 

 the limbs at all. In some cases the affected pigs will be found to 

 assume a kneeling position much of the time. 



After a few days or weeks of these digestive and motor disturb- 

 ances the signs of deformity begin to make themselves prominent. 

 These changes are at first noticeable only in the long bones. The 

 ends of the bones become very much enlarged, and give an appear- 

 ance quite similar to the swelhng of the joints in articular rheuma- 

 tism. By feeling of the swollen limbs the difference may be very 

 easily detected. In rickets the enlarged ends of the bone can be 

 plainly felt. In rheumatism there is no swelling of the bones, 

 simply a filling of the joint itself with fluid. 



Later on in the course of the disease there is noted swelling 

 along the ribs and bending inward of the ribs along the sides of the 

 chest. The swellings on the ribs are often arranged in the form 

 of two rows of button-like elevations a short distance on either side 

 of the breast bone. These rows of small swellings are often re- 

 ferred to as the rachitic rosary, from their resemblance to a string of 

 beads. 



With the continued softening of the long bones of the extremi- 

 ties the weight of the animal forces them to bend, and deformities 

 of various kinds are the result. In the hind legs, where most of the 

 weight of the body comes, there may be actual breaking of the 

 bones. The legs frequently become frightfully bowed, and the 

 animal, as a result, is clumsy and awkward in trying to walk. 



