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PUBLIC RECORD OFFICE

Reference :-

PETC.O. 885

20 PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO

Hremo- globin.

Horses.

Cattle.

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23. As will be seen from what has been detailed concerning both the Central and Western Provinces, the circumstance which most attracts notice is the low state of hæmoglobin, on an average, in all the animals examined, whether suffering or not from trypanosomiasis or any other blood diseases. Taking normal hæmoglobin as being represented by the figure 90 to 100, out of 384 domesticated animals of all sorts examined only 66 were normal as regards hæmoglobin, or the very low average of, roughly, 18 per cent.

The cause for this is probably due in the first instance to the animals either having suffered or being about to suffer from trypanosomiasis, although the parasites may in many cases not have been evident in their blood. Secondly, the in-and-in breeding practised amongst the domestic animals has a most debilitating effect. To these might possibly be added a third cause in the influence of a tropical climate in thinning the blood, apart from the existence of any actual disease.

TRYPANOSOMIASIS.

24. The principal features of this disease appear to be its wide range of distribution, and that, while in cattle it assumes a more or less chronic form, in horses it almost invariably terminates fatally. In the case of cattle the disease might be found to run its course more frequently, were it not for the fact that an infected animal is usually slaughtered by the native owner upon the approach of sickness. As far as the course of the present survey is concerned, constant change from one locality to another has precluded any attempt to follow the entire course of this disease in individual cases, so that it is not at present possible to give its period of duration, or a consecutive train of symptoms in any one animal, with the exception of the experimental animals procured for this purpose, which will be dealt with later.

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25. As far as horses are concerned, the first noticeable symptoms are a dull appearance of the eyes, followed by a watery discharge, which a few days later on becomes whitish in appearance. This is accompanied by a discharge from the nostrils. Congestion of the mucous membranes, although not constant, appears some cases at the outset of the disease, and is usually accompanied by the first rise in temperature. The first rise of temperature usually ranges from 103° to 106° Fahrenheit. The succeeding exacerbations seldom appear to go above 104°, and tucking up of the flanks, at this stage the breathing becomes accelerated with à indicating, of course, lung complications. During the first few days small swellings usually appear about the pendulous part of the belly and the brisket, with enlarge- ment of the scrotum and sheath, accompanied by swelling of the legs. This is followed by weakness, chiefly noticeable in the hind legs. If the animal is made. to walk, its feeble, straddling gait, with knocking together of the hocks and By this time anæmia is fairly knuckling at the fetlocks may at once be noticed. well pronounced; progressive emaciation then takes place, and the animal becomes so weak that once he gets down he may remain in that posture for days. All this time the appetite appears to be good, although the food taken seems to have no nutrient effect. In two or three cases another symptom has also been noticed, Death viz., towards the end of the disease punctiform sores, or sores like punctured wounds, Here note the break out about the fetlocks, and discharge a badly-formed yellowish_pus. is preceded by coma, and the animal expires quietly in this state. fall of hæmoglobin with the progress of the disease. In some cases as low as 40 A yellowish has been registered. On post-mortem naked-eye examinations, which have been very few, nothing has been found sufficient really to account for death. serous infiltration is found in the sub-cutaneous tissues. The flesh is pale and watery. The thoracic cavity usually contains a small quantity of a similar fluid, and occasionally a slight false pleurisy is discernible. The pericardium usually contains an excessive amount of slightly blood-tinged fluid, the outer walls of the heart show petiche, and the heart itself is very firm. The chambers of the heart are usually all full of a firm yellowish clot (ante-mortem), and the blood is generally thin and of a much darker colour than normal. The kidneys are usually soft and friable, capsule adherent, the pelvis of the kidney being oedematous. But all the other abdominal orgens show little or no change. The lungs on section are found to contain a large quantity of the serous fluid mentioned above.

26. Among cattle it would appear from observations made that trypanoso- miasis takes a more chronic form than with horses. Only one opportunity was

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found to follow the disease from its start to the death of the animal. Many cattle were, of course, examined, but it was not possible to observe every stage of the disease, as they usually either died during my absence, or were hidden away by their owners when the malady became pronounced. The special case cited, which happened to be a fortunate exception, was a cow at Onitsha, which prior to the 23rd September showed no outward signs of trypanosomiasis, and on the 13th September the parasites were not discovered on microscopic examination of the peripheral blood. Her hæmoglobin at the time stood at 90, or practically normal. On the 23rd parasites were found in the blood, and hæmoglobin was at 80, but apart from this no outward symptoms of illness were apparent. On the 1st October I proceeded to Idah, and had no opportunity of observing the animal again until the 19th November, when another examination of the peripheral blood showed The symptoms now were: the positive results. Hæmoglobin was down to 40. animal showed extreme emaciation with anæmia, was hide bound, with opacity of both corneas, a whitish discharge from the eyes, and the prescapular lymphatic The cow died during the night of glands could be felt to be slightly enlarged.

the 22nd November. A post mortem was made in the early morning of the 23rd, which, unfortunately, was more or less unsatisfactory, as from all appearances the animal seemed to have died early in the night and decomposition had set in. The following lesions were apparent, however: infiltration of the sub-cutaneous tissue of the belly with yellowish serous fluid, flesh pale, watery, and anæmic looking, and pericardium containing a quantity of dark blood-coloured fluid. The blood separated into a firm, black clot, which completely filled the larger vessels, and a very dark-coloured, watery fluid. Blood smears were prepared from the fluid, but same were useless as decomposition had set in, and showed only severe contamina- tion. The spleen was soft and very friable, the pulp redder than normal, with the matrix broken down. The liver was degenerated, soft, and friable, and faintly bile stained. The kidneys were pale, soft, friable, and oedematous. The urine was slightly bile coloured. The brain was highly congested and surrounded with a faintly Smears were prepared from the blood-coloured fluid, as also was the medulla. pericardial fluid, and the fluid from the medulla and brain, but here, again, exami- nation was unsatisfactory as decomposition had gone too far. Some of the blood was taken into a sterile bottle for the purpose of inoculating another animal, but on microscopical examination it was found that such inoculation would be useless, The duration of the disease in this case may as decomposition had gone too far. therefore be taken as sixty-one days.

27. Regarding animals shown in the table appended as having been examined. Immunity although parasites were found in their blood, and their hæmoglobin was generally in a low state, they did not otherwise show any clinical symptoms of trypanosomiasis, and they seemed to be able to carry the disease for some considerable time withou any marked inconvenience. This appears to indicate that they have acquired a considerable degree of immunity.

28. The number of positive examinations in the Central Province exceeded Increase of those in the Western Province, and from history obtained locally, which was very mortality. vague, the mortality from trypanosomiasis in cattle seems to have been on the increase during the last three years. This increase can only be explained, according to my idea, in the following way. From observations taken it would appear that at some recent time there has been introduced a species of trypanosomiasis differing from that already existing in the native cattle. In my opinion this took place upon the introduction of the West Indian cattle which were placed on the experimental No trace of the original West farm at Akpaka, I believe about the year 1902. Indian herd could be found during my stay at Onitsha, but I was informed that the animals had all died, and that the herd was obliterated by 1904. Although the existing history of them appeared to be very inexact, I gathered sufficient from the native attendant at the Akpaka farm to form the opinion that the West Indian cattle probably died from the local form of trypanosomiasis, and that they in their turn transmitted the West Indian form of the disease to the native cattle of the place. Owing to my short stay in that particular part it was impossible to fully study the morphological characters of a trypanosome, so that from microscopical examination I have not been able to demonstrate to my satisfaction the identity of the two parasites. To do this beyond dispute, of course, requires inoculations into various animals for the purpose of noting the incubation period, the duration of

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