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PUBLIC RECORD OFFICE

Reference :-

wii C.O. 885

22 PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC-

COPYRIGHT PHOTOGRAPH-NOT TO

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corroborate that history. At first the disease was confined to work oxen (animals that had been working exclusively on the Zomba-Blantyre road for several years prior to the outbreak) which inclined one to the belief that infection must have been contracted on the road during the course of their travels. Later, however, cows that had been bred and reared on the Estate and had never been outside its limits were attacked, which puts the matter in a different light. Further inquiries into the matter revealed the fact that two tsetse flies had been caught on the verandah of the dwelling house on the Estate. One of the flies I saw, and can vouch for its being a tsetse fly, Glossina morsitans (?). Mr. Hooker, who knows his Estate thoroughly and is of a distinctly observant turn of mind in connection with matters such as we have under consideration, reasoned that the flies did not breed on his Estate, but that, at certain seasons of the year, stray flies followed natives from the vicinity of one or other of the tributaries of the Shire River, which would account for fly having been found on his Estate, and with this I quite agree. The fact that the Namadidi Estate is in the direct line of an old standing game crossing-game from the Shire watershed going in the direction of the Ntonya Hills--is well known, and although the approach of civilisation may have to some extent destroyed the haunts of the game in this direction they still continue to approach the high grounds skirting the western boundary of the Estate at certain seasons of the year, and by so doing most probably bring with them tsetse fly. The fly, in turn, by following natives, eventually reaches the grazing grounds of the cattle on the Estate. From this short history it will be readily seen that we have a very possible and most probable source of infection for cattle on the Estate in question.

In 1911 an outbreak of the disease occurred among the work oxen of the Public Works Department, Zomba. The animals had been worked only on the Zomba- Blantyre road for twelve months or more prior to the appearance of the disease among them, and had been employed in carting wood for brick-burning purposes from about the 8th mile post to Zomba. They were housed at Nkanda, near the 5th mile post, and their recognised grazing ground lay on the east side of the road and towards the Ntonya Hills, but, owing to the scarcity of grass in that direction, the cattle boys on their own initiative very often crossed the road with their oxen and grazed them on the Namadidi side of the road, often encroaching on the grazing ground of Namadidi Estate. On the appearance of sickness among them the whole herd was subjected, without delay, to à blood examination. Fifteen animals were found to be infected, and they were at once removed to an isolation camp, and the healthy animals continued to work on road but without being grazed on the western side of the road,

them. among and since then no fresh cases have been met with

The two outbreaks just cited, viz., Namadidi and Public Works Department outbreaks, give one good reasons to conclude that the disease must have been con- tracted from stray flies following game or natives, from one or other of the small tributaries of the Shire River, and eventually finding their way on to the grazing grounds of the herds in question; and if this is possible at one point it is also possible at other points further south. That flies have been found in considerable numbers at the foot of the hills lying to the western side of the Namadidi Estate is undoubted. The following memorandum on the subject, handed to me by the Government Entomo- logist, speaks for itself :-

At the beginning of January, 1912, I visited the Namadidi Estate, where I stayed two or three days, and while there searched the low ground towards the Lindipi and Namitembo streams for Glossina morsitans. On the first day I proceeded along the old game path towards the Lindipi.

On this occasion no morsitans were found. On the next day I went along the old Mpimbi Road. About a mile from the stream which skirts the foot of the plateau a few tsetse (G. morsitans) were found. They came flying round while I was resting, sitting on a rock.

The country was typical of the lower elevations in the Protectorate; the grass was short and there was no undergrowth. Natives are continually passing along this road on their way to Zomba and must pass through the Namadidi Estate. It is quite possible, therefore, for "fly " to be brought up by natives, and thus the cattle at Namadidi grazing near the road would be likely to get bitten. It is well known that morsitans will travel long distances on people's backs without biting them as long as they are moving, a habit of which I have had experience, and I regard the Mpimbi Road as the source from which flies are introduced into the Highlands. This is, of course,

With

conjecture, and without organised collecting and observations over a long period it could not be proved. Search for tsetse between the Zomba Road as far as the sixth mile stone and the Namadidi Estate revealed nothing. the extremely limited resources at my command a great deal cannot be deduced from this fact, but on the whole it seems that G. morsitans does not breed at this altitude (about 2,900 feet), but stray infected flies are being continually

Game also comes up

and brought up by travellers from the lower elevations. it is again possible that it carries flies with it. Returning now to the outbreaks which have occurred during the twelve months with which this report deals, the first to be noted is that on Glenbreck Estate, 10 miles from Zomba, the subject being a half-bred cow which was purchased in the Blantyre Show the previous year (July, 1911), and since then was grazed exclusively on that Estate and remained in good health until the 25th of May, 1912, when trypano- somes were found in its blood. Following this, on the 26th of June of the same year the disease appeared among work oxen belonging to the British Central Africa Company, Blantyre, which had been working only on the Blantyre-Zomba Road for a period of twelve months or more, and were outspanned and grazed at various points along that road.

Next, on the 4th of July, 1912, the disease appeared among cattle belonging to the Blantyre and East Africa Company, Inchgordon Estate, 19 miles from Zomba. From conversation with the Agent of that Estate I gathered that a few months prior to the appearance of the disease the animals had been grazed on the western side of the road, and that eland had been seen in close proximity to the cattle in the course of their grazing.

The next outbreak on this transport route appeared among work oxen on A. L. Bruce Estates, Limited, Magomero, in May, 1913. So far no case of the disease has been diagnosed among other animals on the Estate, that is to say, among animals that have not been used for transport praposes. The transport animals have been worked only on the road between Magomero and Limbe or Blantyre for several years past, except one team, which did one journey to Zomba a year ago.

Returning once more to the Namadidi outbreak, we have in it more or less distinct evidence of the disease having been contracted from the Shire watershed. and the other cases enumerated appear to me to be capable of having been contracted at one or other points at varying distances from the road along the large water- course leading from Lake Nyasa. The large fly belt which commences, we might say, on the shores of Lake Nyasa extends more or less regularly along the outlet of that Lake for a considerable distance southwards, and the instance of the presence of fly on one of its tributaries as far south as Zomba gives good grounds for reasoning that similar instances must be expected further south.

32986

SIR,

*

No. 52.

G. GARDEN,

Veterinary Officer.

COLONIAL OFFICE to FOREIGN OFFICE. [Answered by No. 55.]

Downing Street, 4 October, 1913. I AM directed by Mr. Secretary Harcourt to acknowledge the receipt of your letter of the 22nd of September,* with its enclosures, respecting the attitude of the French Government towards the proposal for raising the limit of weight of elephant tusks for trading purposes in Africa.

2. Mr. Harcourt considers that the proposal of the French Government for the appointment of an International Commission offers some prospect of agreement. and should be accepted.

3. If the other Powers concerned are also willing to accept the proposal, London would appear to be indicated as the most suitable place for the meeting of the Commission, as the first International Game Conference was held here in 1900.

• No. 48.