ENLARGEMENT OF THE MESENTERIC GLANDS. 333 



A circular muscle, the sphincter, is always in action at the termi- 

 nation of the rectum, to prevent its contents from being involunta- 

 rily discharged. Its power is just sufficient for the purpose ; and 

 it readily yields, when by the pressure of the abdominal muscles 

 and the diaphragm, the excrement is forced against it, in the vol- 

 untary efforts of the animal. 



The contents of the rectum in cattle are semi-fluid — their nutritive 

 qualities are nearly exhausted, and they are of very inferior value 

 for agricultural purposes. 



THE DISEASES OF THE INTESTINES. 



These are too numerous, and destroy too many of our cattle. 

 Those which belong to the membranes that invest or line the intes- 

 tines, and that are referable to the greater part, or the whole, of 

 their extent, will with most convenience first come under consideration. 

 Those which affect only particular viscera, or parts of them, will 

 naturally follow. 



ENLARGEMENT OF THE MESENTERIC GLANDS. 



It has been stated that there are numerous vessels, termed lacteals, 

 opening on the inner coat of the intestines, in order to convey the 

 chyle to the thoracic duct, so that it may mingle with and supply 

 the waste of the blood. These little vessels, ere they reach the main 

 trunk, pass through a glandular body, in which some unknown 

 change is probably effected in the chyle. Some of these mesenteric 

 glands are represented at Jig. 8, p. 330. These glands occasionally 

 become unnaturally enlarged, and then, whether from the abstraction 

 of so much nutriment, in order to contribute to this enlargement, or 

 from the unknown change not taking place in the chyle before it 

 mingles with the blood, or from the constitutional disturbance which 

 the presence of such a body in the abdomen i»iust produce, the 

 animal ceases to thrive, his belly becomes enlarged, cough and con- 

 sumption appear, and he gradually wastes away and dies. On exami- 

 nation after death, some of the mesenteric glands are of unusual bulk, 

 and occasionally have grown to an enormous size. 



A cow having an internal tumor, showing on the right side, died. 

 On opening the abdomen, the first thing that presented itself, filling 

 the iliac region, was a lai-ge mesenteric gland, of irregular form, wei^rh- 

 ing 160 pounds. On making a section through it, its appearance was 

 chiefly that of a schirrous deposit. The mesenteric glands generally 

 were unhealthy, and many of them were schirrous. This case is a valu- 

 able one ; it is the only one on record of schirrous enlargement of the 

 mesenteric glands of the ox ; but the recollection of every practitioner 

 will fuinisli him with not a few instances of these tumors unexpectedly 

 presenting themselves on examination of the abdomen. They have 

 been found chiefly in young beasts that had been bred too much in 



