Part 9

TABLE 6. _Differential Percentages of Leucocytes._ _The Figures are based upon Counts of Two Hundred Cells upon Two Slides unless Otherwise Specified. Blood Films were taken from Apparently Healthy Animals in the Exhibition Cages._ ════════════════╤════════════╤═══════╤═══════╤═══════╤══════════╤══════════════════ Animal │ Polymor- │ Small │ Large │Eosino-│ Special │ Notes │phonuclears.│Lympho-│Mononu-│philes.│ │ │ Per cent. │cytes. │clears.│ Per │ │ │ │ Per │ Per │ cent. │ │ │ │ cent. │ cent. │ │ │ ────────────────┼────────────┼───────┼───────┼───────┼──────────┼────────────────── Potto │ 20.│ 67.│ 7.1│ 5.9│ │ Perodicticus │ │ │ │ │ │ potto │ │ │ │ │ │ Rhesus Macaque │ 30.2│ 61.4│ 5.6│ 2.8│ │ Macacus │ │ │ │ │ │ rhesus. │ │ │ │ │ │ │ (Av. 5 counts) │ │ │ │ Raccoon-like Dog│ 62.2│ 32.│ 2.│ 3.8│ │ Canis │ │ │ │ │ │ procyonoides. │ │ │ │ │ │ Swift Fox Canis│ 65.│ 18.│ 13.│ 1.│ 3 per │ velox. │ │ │ │ │cent. Baso│ Dingo Canis │ 77.│ 15.4│ 3.8│ 3.8│ │ dingo. │ │ │ │ │ │ Timber Wolf │ 76.5│ 15.5│ 3.5│ 4.5│ │ Canis │ │ │ │ │ │ mexicanus. │ │ │ │ │ │ Wild Cat Felis │ 55.8│ 34.│ 7.│ 3.8│ │ ruffus. │ │ │ │ │ │ Gray Ichneumon │ 52.6│ 44.4│ 2.3│ .7│ │ Herpestes │ │ │ │ │ │ mungo. │ │ │ │ │ │ Indian │ 66.│ 20.│ 14.│ 0.│ │ Paradoxure │ │ │ │ │ │ Paradoxurus │ │ │ │ │ │ niger. │ │ │ │ │ │ Large spotted │ 60.│ 31.2│ 1.2│ 7.6│ │ Civet Viverra │ │ │ │ │ │ megaspila. │ │ │ │ │ │ Ocelot Felis │ 79.│ 15.6│ 3.5│ 1.9│ │ pardalis. │ │ │ │ │ │ Texas Skunk │ 44.1│ 46.3│ 4.3│ 5.3│ │_a._ There are Mephitis │ │ │ │ │ │several grades of mesomelas. │ │ │ │ │ │eosinophilic │ │ │ │ │ │granulations, │ │ │ │ │ │ranging from very │ │ │ │ │ │fine to very │ │ │ │ │ │coarse. They are │ │ │ │ │ │entirely discrete, │ │ │ │ │ │however, and the │ │ │ │ │ │eosinophile cells │ │ │ │ │ │are quite distinct │ │ │ │ │ │from the │ │ │ │ │ │homogeneous │ │ │ │ │ │neutrophiles. Tayra Felis │ 75.6│ 19.2│ 4.1│ 1.1│ │ tayra. │ │ │ │ │ │ White nosed │ 60.│ 20.│ 18.│ 2.│ │_b._ The Coati Nasua │ │ │ │ │ │protoplasm of the narica. │ │ │ │ │ │leucocytes shows │ │ │ │ │ │practically no │ │ │ │ │ │stain. Mitotic │ │ │ │ │ │figures are │ │ │ │ │ │frequent among the │ │ │ │ │ │polymorphonuclear │ │ │ │ │ │cells. The small │ │ │ │ │ │lymphocytes show │ │ │ │ │ │basophilic │ │ │ │ │ │granules. Crab eating │ 45.│ 42.│ 2.5│ 10.5│ │ Raccoon. │ │ │ │ │ │ Procyon │ │ │ │ │ │ cancrivorous. │ │ │ │ │ │ Ring tailed │ 39.2│ 54.7│ 4.3│ 1.8│ │ Bassaris │ │ │ │ │ │ Bassariscus │ │ │ │ │ │ astutus. │ │ │ │ │ │ Kinkajou Potos │ 47.4│ 42.5│ 6.│ 4.1│ │ caudivolvulus.│ │ │ │ │ │ Common Raccoon │ 46.│ 42.9│ 7.4│ 3.7│ │ Procyon lotor.│ │ │ │ │ │ Texas White │ 67.│ 19.│ 11.│ 3.│ │ footed Mouse │ │ │ │ │ │ Peromyscus │ │ │ │ │ │ leucopus. │ │ │ │ │ │ Kangaroo Rat │ 55.│ 33.│ 6.│ │ 5 per │_c._ Many Perodipus │ │ │ │ │ cent. x │leucocytes were richardsoni. │ │ │ │ │ cells. │noted, with deeply │ │ │ │ │ │staining nuclei │ │ │ │ │ │filling up most of │ │ │ │ │ │the cells. The │ │ │ │ │ │protoplasm was │ │ │ │ │ │colored a deep │ │ │ │ │ │brown. These were │ │ │ │ │ │called x cells │ │ │ │ │ │pending │ │ │ │ │ │investigation. Polecat Mustela │ 42.4│ 54.6│ 2.1│ .9│ │ putorius. │ │ │ │ │ │ Common Opossum │ 44.│ 39.│ 7.│ 9.│ 1 per │_d._ Polynuclears Didelphys │ │ │ │ │cent. Mast│quite large, with virginiana. │ │ │ │ │ cells. │deeply staining │ │ │ │ │ │nuclei which are │ │ │ │ │ │in many instances │ │ │ │ │ │entirely separate │ │ │ │ │ │and distinct. Bridled Wallaby │ 58.3│ 38.8│ 2.│ 4.2│ │ Onychogalea │ │ │ │ │ │ frenata. │ │ │ │ │ │ Six banded │ 57.1│ 23.2│ 6.3│ 13.4│ │ Armadillo │ │ │ │ │ │ Dasypus │ │ │ │ │ │ sexcinctus │ │ │ │ │ │ Elephant Elephas│ 15.│ 47.4│ 7.6│ 5.8│ (Bilobed │_e._ The ordinary indicus. │ │ │ │ │ 23.8) │polymorphonuclears │ │ │ │ │(Basophile│are very few in │ │ │ │ │ .4) │number, and those │ │ │ │ │ │seen have nearly │ │ │ │ │ │all a faint │ │ │ │ │ │acidophilic or │ │ │ │ │ │basophilic │ │ │ │ │ │character. The │ │ │ │ │ │eosinophiles are │ │ │ │ │ │quite distinct and │ │ │ │ │ │their granulations │ │ │ │ │ │are large and │ │ │ │ │ │globular. The │ │ │ │ │ │cells called │ │ │ │ │ │bilobed are │ │ │ │ │ │unusual and can │ │ │ │ │ │probably best be │ │ │ │ │ │accounted for as │ │ │ │ │ │directly dividing │ │ │ │ │ │small lymphocytes. │ │ │ │ │ │The staining │ │ │ │ │ │properties and │ │ │ │ │ │shape of the │ │ │ │ │ │nuclei of the │ │ │ │ │ │bilobed cells are │ │ │ │ │ │most closely │ │ │ │ │ │related to the │ │ │ │ │ │lymphocytes. They │ │ │ │ │ │are not always │ │ │ │ │ │regular, however, │ │ │ │ │ │but may be almost │ │ │ │ │ │as irregular as │ │ │ │ │ │the polynuclears. │ │ │ │ │ │In practically │ │ │ │ │ │every instance, │ │ │ │ │ │however, a │ │ │ │ │ │connecting isthmus │ │ │ │ │ │may be found │ │ │ │ │ │between the │ │ │ │ │ │spherical nuclear │ │ │ │ │ │portions. No │ │ │ │ │ │mitotic figures │ │ │ │ │ │seen. The │ │ │ │ │ │protoplasm is │ │ │ │ │ │homogeneous and │ │ │ │ │ │pale blue or lilac │ │ │ │ │ │in relatively │ │ │ │ │ │large amount. No │ │ │ │ │ │granules were ever │ │ │ │ │ │seen. ────────────────┴────────────┴───────┴───────┴───────┴──────────┴──────────────────

It would seem, from a general observation of simple and infected wounds and from a few blood counts, that the response of leucocytes in the lower animals is greater than in monkeys and man. The ease with which animals endure a wound and the rapid local pus formation about an infection speak for an easy mobilization of their cellular defenders; their connective tissue elements seem equally well brought into play. In so far as birds are concerned perhaps the normally large number of leucocytes and the participation of local tissue cells in response to irritation is a preparatory protective mechanism because of their relatively small amount of bone marrow which may not be able to mobilize new cells rapidly; many of the birds, notably those prepared for long flight, have much of their osseous system given over to air space. The number of red blood cells is also greater in Mammalia, which show a variation from 4,000,000 per cubic millimetre in some small genera to 12,000,000 per cubic millimetre in some ungulates, while birds vary from 2–5,000,000 per cubic millimetre. Despite these fundamental differences in the classes, pathological changes of anemia, leucocytosis and leucemia are comparable; polycythemia in lower animals is unknown to me but may of course occur.

ANEMIA.

As in human pathology this condition may be divided into the group that follows some disease which damages the red blood cells or their source, called secondary, and those cases not preceded by such a condition, called primary. Formerly this latter group, known as progressive pernicious anemia, was copiously represented, but study has discovered that worms, inorganic poisons and infections can produce a picture of grave anemia so that the formerly large group has dwindled. We now conceive a primary anemia to be one without discoverable responsible antecedent pathology, therefore a disease of the bone marrow itself. There is one variety, hemolytic anemia, which seems to be an intoxication of the bone marrow with solution of red cells, but the affected tissue puts up some struggle against the poison. In another primary, the so-called aplastic anemia, no activity at all is shown by the marrow, no young cells appearing in the circulation. Clorosis, or green sickness of young persons, is a primary anemia and presents itself as a moderate cell reduction with a disproportionately low hemoglobin percentage. As a disease entity this does not occur in the lower animals, so far as I am aware, but a very few hemoglobin estimations and a reference to the literature would indicate that well marked hemoglobin anemia does occur.

In so far as the pathology of anemia is concerned we are obliged usually to judge by the appearance of the blood and tissues, the yellowish pallor of the mucous membranes, the condition of the marrow and the amount of pigment; severe rapid cases show hemorrhages and prolonged cases have fatty degeneration of the parenchymatous organs. For a decision of the primary or secondary nature we must judge the accompanying pathology and the condition of the bone marrow.

SECONDARY ANEMIA.

Secondary anemia can be laid in general to insanitary housing or inappropriate diet over a long period, to chronic bacterial infection of low grade, to the action of blood parasites or those of the bowel which either suck blood or elaborate an absorbable toxin, or to single great or repeated small hemorrhages. We shall now consider the cases at the Garden. Perhaps many other animals have had a substandard blood, but these are the cases in which the gross appearance attracted close scrutiny in this direction. London has had much anemia, probably from their reported heavy infestation with parasites, but this factor has with us apparently played a small rôle in the production of anemia.

IN MAMMALIA.

In so far as the Primates are concerned the one outstanding cause of anemia is degenerative disease of the osseous system. In both rickets and osteomalacia there is an irregular hyperplasia of the marrow, which is usually more marked in the latter. In osteomalacia one finds irregular areas of congestion or even hemorrhage besides masses of a gelatinous fatty tissue while scattered about are pink spots where the marrow is better preserved. In rickets, on the other hand, the tissue is more uniformly congested and less sharply separated from the endosteal osseoid material or the irregular epiphyseal spongiosa. The fibroid or osteoid growth of osteomalacia seems to be fairly well differentiated from the marrow tissue although it may send strands into the canal and across the spongy area. Histologically there is not a distinct difference in the appearances nor do they differ from the human analogue. In those cases which develop late in life the red cell centres are very few in number but usually active. In the blood, one finds a few nucleated and stippled cells, but not much change in size and shape of the erythrocytes.

It does not seem that the anemia can be the cause of death, for among our thirty-nine cases of osteomalacia and rickets, the prosectors have thought it of sufficient importance to record in the diagnoses but eleven times. There are usually complications of pneumonitis or enteritis to finish the animal before the poverty of the blood will do so, and our records show only a Black Spider Monkey (_Ateles ater_), a Silky Marmoset (_Leontocebus rosalia_) and a macaque (sp.?) with osteomalacia and grave secondary anemia. It would seem, however, that hemoglobin anemia must exist, for, despite one record of 40 per cent., Fleischl, no excess of pigment deposit is noted in the spleen, liver or marrow.

Carnivora have shown a moderate number of diseases of the skeleton but the occurrence of a marrow involvement seems less frank, although the anatomical changes are similar. However, there are three grave secondary anemias recorded in eleven carnivores suffering from osteomalacia and rickets. Another prime cause of low blood value in this order is gastrointestinal inflammation; in seventeen cases of anemia, of secondary nature, five showed gastroenteritis of severe grade or protracted character. Perhaps the most prolific single cause of this blood change is parasitism, six of the seventeen cases showing infestation, five of which are nematodes and two cestodes, one showing both. The details of these are worth recording. Two young Jungle Kittens (_Felis chaus_) from the same litter died of enteritis with a noticeable anemia; they harbored in their upper small intestine ascarids, and one of them had a few hookworms (sp.?). A Kinkajou (_Potos caudivolvulvus_) died from a general mild infection, emanating from a pneumonia perhaps, and showed a heavy infestation with tænia (sp.?). An American Wild Cat (_Felis ruffus_) died from acute catarrhal enteritis and anemia; the parasitological findings included Filaria fasciata, adults in abdominal and gluteal muscles, larvæ in the blood; Dibothriocephalis felis, Ascaris mystax and Uncinaria canina in the small intestines. While the blood was thin and pale and some pigmentation existed, the condition could not be called a picture of grave anemia. A noteworthy finding was the deep pigmentation of almost the entire intestinal wall. Ascaris mystax was found in an under-sized inbred gray wolf, killed because of poor coat; there was a marked anemia and atrophy of the skin. An Ocelot (_Felis chibigonazon_) gave a picture of anemia due to uncinariasis, but is not so instructive as the following. A Swift Fox (_Canis velox_) exhibited clearly a case of progressive secondary anemia from uncinaria, and the history is worthy of a brief recital.

Muscles atrophic, greenish black over abdomen. Fat absent. Lung is blotched by darker red markings where parenchyma contains distinct excess of frothy pink watery fluid. No fluid or adhesions in pericardium. Heart is contracted, and muscle is pale yellow and firm. The only abnormality consists of slight yellowing of musculature. The abdomen shows great omentum firmly adherent to fundus of bladder. No fluid or other adhesions in abdomen. The liver is normal in size, smooth in surface and has sharp edges, is friable and bright orange yellow. The section surface is glistening, smooth and dry. Organ is poor in blood content, greasy and breaks easily. Bladder is large, contents fluid green bile; duct patulous. Spleen normal. Kidney is small and smooth, diminished in bulk, normal location, smooth surface, and pale yellowish gray, consistency, soft, flabby. Ureters normal. Mouth and teeth normal. Stomach contains scanty brown fluid. Duodenum— Mucosa bile-stained, contained a solitary nematode worm. In its lower portion it becomes filled with a blackish red fluid, and its mucosa becomes studded by heavily outlined punctate hemorrhages whose positions are best seen through serosa. Jejunum similar in condition to duodenum and contains four small nematode worms. At one point, i.e., where the worm is located at beginning of ileum the blood staining of mucosa is strictly in neighborhood of the worm. Capillaries nowhere congested. Ileum contains slight amount of brownish black material, mucosa normal. Large intestine and rectum normal. Pancreas normal. Lymphatics normal. This is a case of death by anemia as result of bites of hookworms. There were certainly more than four worms present antemortem since no males were found, and this may be explained by a possible diarrhœa which has flushed them out. This idea is borne out by empty condition of gastrointestinal tract. Animal Parasites—Uncinaria canina. The four small nematode worms above mentioned conform in all respects to the given anatomical points of uncinaria. All four specimens are perfectly formed females. The location of the hooks was easily determined and established as being in the most dorsal portion of buccal cavity, and as projecting forward and ventrally in two groups of three each in same manner as described heretofore in similar infestations in foxes. The large nematode worm found in duodenum is, from its possession of three lips and its general form, an ascaris. The mustache, however, which is so commonly seen in ascaris worms from this region is absent. Postmortem blood of heart shows red cells granulated and almost worthless for histological study. Nucleated reds, however, are absent but other points valuable in settling the question of anemia cannot be determined.

Lung.—There are no abnormalities in supporting tissue. Alveolar walls are markedly congested. Bronchi normal and show no trace of larval hookworm infestation. Air sacs contain many red blood cells together with a few heart-failure-cells. Congestion of lung.

Liver.—No excess of fibrous tissue. Finer details of structure cannot be made out owing to advanced autolytic changes. The only possible pathological changes consist of localized areas where liver cells have fused to form notable masses of pink granular material suggesting local necroses. Autolysis.

Intestines.—Four sections are present and all show essentially the same character of changes. Interstitial tissue between muscular tissue and submucosa loosely arranged as though separated by edema.