ABSTRACTS                                         355

Zoologische Beitrage zum Surraproblem. XXV. Ueber den Einfluss verschie-
dener Versuchstiere auf das Ergebnis von Surraubertragungsversuchen mit
Stomoxys calcitrans. [ Influence of different experimental animals on the results
of experiments in the transmission of surra by S. calcitrans.] Nieschulz, Otto.
Centralbl Bakt. I Abt. Orig. 113 (1-2): 80-89. 1929.

With over 3600 individuals of S. calcitrans 103 experiments were made by direct transmission
in which horses, monkeys, rabbits, guinea pigs, rats and mice were employed as carriers of surra or as
subjects for infection. It was shown that the result of transmission may be decidedly influenced by
the kind of animal to be infected, while the particular species used as carrier plays only a subordinate
part. Horses were much less easily infected than small experimental animals, whatever the species of
surra carrier used. The average expectation of positive transmission of surra in these experiments
was : in horses 1 : 150, in rabbits, guinea pigs and rats 1 : 23, and in mice 1 : 155.— E. M. Walker.
[ Reprinted from the Biological Abstracts, 5, 3, March 1931.]

Zoologische Beitrage zum Surraproblem. XXVI. Uebertragungsversuche mit
Tabanus rubidus Wied. nach langeren Intervallen. [ Experiments on transmission
of surra with T. rubidus after considerable intervals of time.] Nieschulz, Otto.
Centralbl Bakt. I Abt. Orig. 113 (1-2) : 89-93, 1929.

Two series of experiments on the transmission of surra by T. rubidus Wied. gave negative results.
A considerable number of the flies were used, all of which had been previously infected from surra
horses and then, after 1-84 days, were fed upon healthy horses (7434 times; in all). Negative results
were also obtained from the subcutaneous injection of 2 horses, each with the intestinal contents of
100 individuals of T rubidus which had been fed respectively 15 and 30-31 days previously upon
surra horses. E. M. Walker. [ Reprinted from the Biological Abstracts, 5, 3, March 1931.]

Avian pest, a disease of birds hitherto unknown in the Philippine Islands.—Estefano

                                                      C. Farinas.

                                                   CONCLUSIONS.

1. Progress in the investigation of a hitherto unknown disease of the avian family in the Philip-
pine Islands, for which we proposed the name of avian pest, is herewith reported.

2. This disease is caused by a filter-passing virus, and may be described as an acute, febrile,
infectious disease characterized by dyspnœa, diarrhœa, and inappetence, with nerve injury which is
manifested by various locomotor disturbances in birds that survive the acute attack.

3. This disease is identical with the Newcastle disease of England, pseudo-fowlpest in Java and
Ranikhet disease in India.

4. The average incubation period of artificial infection is 4 to 5 days ; the average course of the
disease is 2 to 4 days after the symptoms have appeared.

5. The mortality in newly infected flocks ranges from 10 to 100 per cent.

6. Natural infection is brought about by the ingestion of virus through food or water.

7. Artificial infection can be produced by introducing the virus by the mouth, under the skin
into the muscles, into the blood vessels, introcularly, in the conjunctiva and by the cloaca, but not by
means of sexual contact or scarification.