SECTION VII THE ALIMENTARY TRACT. PART 1.—PHARYNX, ESOPHAGUS, STOMACH AND INTESTINES (continued 2)

Among the Aves the following cases only are worthy of report. A parrot (Melopsittacus undulatus) was found to have a tightly packed mass of worms in the end of the duodenum above which the bowel was distended, elongated, doubled on itself and of a deep red color; below this the small intestine was empty. A closely similar condition was found in a Screech Owl (Otus asio asio) the obstruction occurring just above the end of the small gut. A Sparrow Hawk (Falco sparverius) had an invagination two cm. in length, a short distance above the end of the small intestine. No peritonitis existed but the presence of an acute enteritis helps to explain the intussusception.

Hernia.

Hernia is not a common occurrence among the lower animals but our experience is instructive in two particulars, to wit, its absence in the orders preceding the Rodentia and the frequency of the traumatic variety. There being no general remarks to be made upon the subject, it seems well to give a summary of the findings in each of the seven cases.

A Western Fox Squirrel (Sciurus rufiventer) showed a diaphragmatic defect on the right side, a rounded opening with smooth edges, through which a loop of intestine had passed, entering behind the liver and reaching into the pleura as high as the pulmonary apex where it was adherent; this was probably of long standing. Two more loops were found wedged in the diaphragmatic hole, one of which was gangrenous.

An Indian Antelope (Black Buck) (Antilope cervicapra) presented an irreducible incarcerated but not strangulated umbilical hernia. The peritoneum was fused 217with the aponeurosis at the ring but the gut was not adherent at this point while it was attached within the sac outside the muscle, thus forming the incarceration. Apparently the sac had dissected between the muscular layers for it could be followed for several centimetres in some directions. A Hog Deer (Cervus porcinus) had apparently suffered an injury in the flank for at one point the muscles were irregularly cicatrized and a rent was present through which several loops of intestine and a band of omentum had escaped, being adherent to fascia. No injury to the skin was apparent.

Another Indian Antelope showed a clean traumatic rupture of the muscle and peritoneum in the right inguinal region without penetration of skin. An acute hernia had occurred which was lightly adherent to fascia and an acute peritonitis was beginning. The bowel was however not strangulated.

An aoudad (Ovis tragelaphus) seems to have suffered an injury by a pointed object (horn?) just to the right of the ensiform cartilage for at this position there is a circular hole, with smooth healed edges, in the aponeurosis, permitting the emersion of a peritoneal sac containing omentum. All parts were adherent but no acute inflammation existed.

What may have been a hernia or a relaxation of the transversus perinei was observed in an Undulated Grass Parrakeet (Melopsittacus undulatus). A bulge about the size of the finger end was seen externally, beside and behind the anus. This proved to contain several loops of bowel and a mass of fat.

A lateral abdominal hernia was seen in a Barbary Turtle Dove (Turtur risorius). It consisted of a peritoneal sac and two loops of intestine. This protrusion, while firmly fixed in its unnatural position, was in no way constricted.

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Rectal Prolapse.

Prolapse of the rectum may in a sense be looked upon as a hernia or at least as a relaxation of the anal and perineal muscles with protrusion of parts normally situated intracorporeally. Although not frequent it has been incurable in the animal, as it frequently is in man without operation, a measure we have not adopted. Just what determines weakness in the pelvic outlet is entirely obscure for indeed we have seen here wounds and inflammations of the perineal area without prolapse of the rectum and in none of the cases of prolapse did the pelvic floor seem injured or diseased. It is but speculation to blame the annular muscles of the anus. Tenesmus, or at least reasons for this straining action, have been sought, with the result that in our cases lesions of the egg-laying apparatus in birds and enteritis in mammals have stood out most prominently. In no case have hemorrhoids been encountered nor has a tumor pendant from the colonic mucosa, drawn the bowel toward the anal opening. It might be added parenthetically here that hemorrhoids are practically unknown for quadrupeds, Hutyra and Marek failing to mention them independently and only one reference being found in the Jahresbericht fur Veterinär Medizin (Schmidt 1914–169); this case is more like angioma than hemorrhoids. If tenesmus be active in the production of rectal prolapse then it would have to be assumed that this straining effort can be induced by enteritis since eversion of the rectum has occurred with this disease in the absence of colitis, the condition usually expected in the presence of tenesmus. The thirteen cases have been seen in Mammalia, 8, (Carnivora, 2, Rodentia, 1, Ungulata, 3, Edentata, 1, Marsupialia, 1) and Aves, 5, (Passeres, Picariæ, Striges, Psittaci and Galli each one). Three mammals had enteritis, one had foreign bodies in the bowel and one had many ascarids; three had no demonstrable or suggestive causes. Two of the five birds 219had enteritis high in the tract, one had uratic calculi in the cloaca, and three had trouble in the egg-laying apparatus: one too large an egg, one a broken egg and one a salpingitis.

Diverticula.

It is almost certain that in a human pathological service of fifty-five hundred autopsies, one or more diverticula of the Meckel variety would be encountered and perhaps several of other kinds. In our material only pouchings or false diverticula of the colonic wall are recorded, and our personnel has often spoken of the absence of these gross abnormalities of the alimentary tract. The two cases, notes of which are given, are instances of hernial pouchings of the colonic mucosa and serosa, a condition which is well known in human medicine. It may be said to occur in two varieties, one in which the pouchings have heavy walls formed by a thickened mucosa, muscularis and peritoneum and one in which the bulgings have delicate walls, then being small herniæ of the inner coats through rifts in the outer. Such a division is probably unnecessary or misleading since the latter may be only a forerunner of the former. However the clinical evidence of the simple variety is scanty and may be little more than constipation while the peritonitic variety gives a clinical picture of pain, constipation and a mass in the left abdominal area, then known as diverticulitis or pericolitis sinistra. In these cases the colon is much distorted by the irregularity of its mucosa and by inflammatory thickening of the muscularis and serosa. Diverticula arise from defects of the muscular coat, or secondarily after inflammation or prolonged constipation, by weakness of muscle, or as hernial protrusions around the entrance of blood vessels where the muscle is thin. Such sacculations permit feces to collect and continue the inflammation, thus further weakening the gut and producing constipation, the whole vicious cycle being favorable 220to the formation of more sacculations; coproliths may form in the diverticula. The two monkeys now reported seem to have varying grades of the same condition, a long standing colitis with diverticula, constipation and the collection of inspissated feces in the sacculations. These animals did not have hemorrhoids.

Black Ape ♀ (Cynopithecus niger). Coprostasis. Coproliths in diverticulum. Chronic colitis. Cor bifida. The large intestine is of the same calibre as the small intestine should be when not distended. The sacculations as seen before opening the organ are salient, forming distinct pouches. In one or two cases they are so pronounced as to constitute diverticula 7 cm. long. In two instances the serosa at the fundi of these diverticula is markedly hyperemic and very thin. In many cases the sacculations contain coproliths. The wall of the organ is distinctly thickened, puckered, inelastic and opaque. Mucosa is thrown up into coarse rugæ.

Japanese Macaque ♂ (Macacus fuscatus). Chronic hypertrophic colitis. False diverticula of colon. The large intestine contains a moderate quantity of quite constipated feces. The serosa is smooth. The wall shows at several stretches enlargements of the normal sacculations, forming false diverticula. The wall of the gut in these herniæ is thinner than in the surrounding parts; no ulcers exist; no local peritonitis is present. The mucosa everywhere is irregular in thickness, less translucent than normal and thrown into irregular rugæ; tenacious mucus covers it. No ulcers.

Tumors.

Only one tumor was observed in the mammalian intestinal tract proper. Dasyure (Dasyurus maculatus) Adenocarcinoma of the intestines. On postmortem there was a pale diffuse thickening of the coats of the small gut over a large area; numerous soft, light yellow, sharply circumscribed, elevated (like secondary tumors) nodules in the liver and spleen, and a pea-size whitish nodule around a bronchus in the right lung. Histological section of primary growth not made but a cross section of the intestine in the vicinity shows an adenomatous change with considerable increase in the connective tissue. The nodules in the liver, spleen and lung and the appearances of the abdominal lymph nodes, found microscopically, are precisely similar. They consist of irregularly arranged 221epithelial nests and distorted acini, around which are sharply outlined spaces, filled with the remains of degenerated blood or a granular material. The metastases are always sharply outlined.

Aves supply three papillomata which are interesting in that one occurred in the proventricle, and two grew in the duodenum in the vicinity of the upper biliary opening and presented within the lumen soft masses which, while not occluding the passage, offered some little obstruction as indicated by a slight distention above their location. In two, carefully studied, no indications of parasites or of cancer could be found. The birds concerned were an amazon, an owl, and a rhea.

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