Annual report of the Veterinary Department, Sudan Government.

  • Sudan. Veterinary Department.
Date:
[1925]
Catalogue details

Licence: Public Domain Mark

Credit: Annual report of the Veterinary Department, Sudan Government. Source: Wellcome Collection.

    46/56 (page 40)
    Reference to Table 6 shows that in camels 49 and 75 a positive reaction to the Formol-Gel test developed after 5 and 6 weeks re¬ spectively, whereas in camel 1052, cured of the disease, the reaction to the Formol-Gel test developed after 7 weeks. Under this heading reference will be made to the two camels (1569 and 1474) shown in Table 5 which, although negative to the Formol-Gel test, showed trypanosomes in their blood. No. 1569 was treated with Naganol on 13.1.25, and 1474 was not treated. Three and a half months afterwards both were subjected to the Formol-Gel test. The untreated one had by this time developed a positive reaction to the Formol-Gel test whereas the treated camel was still negative. The question arises as to whether all camels suffering from Trypano¬ somiasis react to the Formol-Gel test. Seventy-seven camels diagnosed microscopically as Trypanoso¬ miasis were tested, and 75 of these reacted. The two exceptions were 1569 and 1474 referred to above. In conjunction with the evidence obtained in Table 6 we can conclude that these two were recent infections and that the power to react had not had time to develop. Immunity. The question which presents itself very readily is whether a camel, having suffered from Trypanosomiasis and been cured by Naganol, has an immunity against re-infection. The question is one of im¬ portance. If the Naganol only cures the camel of trypanosomiasis and does not leave any immunity it is comparable with having a new healthy camel, but if on the other hand the camel is cured and is also immune against the disease we have a camel much more valuable than a camel that has never suffered from the disease. It is known that as a rule if an animal recovers from trypanoso¬ miasis it has a certain degree of immunity. This immunity is very specific, and only for the species of trypanosome from which the animal suffered. The re-iufection experiment on camel 1052, and shown in Table 6, was carried out to ascertain if any immunity was present against the disease after cure. Two camels free from trypanosomiasis were used as controls. It will be seen that the appearance of trypanosomes in the blood was delayed up to 23 days in the case of camel 1052, whereas in the control camels trypanosomes appeared in the blood in 8 and 7 days. Although the trypanosomes appeared in the blood of camel 1052, no symptoms of the disease were present. The trypanosomes were scanty, only intermittently present, and the animal remained in good condition for three months, when it was destroyed still in good condition Compared with this the two control camels, 49 and 75, developed a per-acute attack of trypanosomiasis.