ABSTRACTS

                               Transmission of Fowl-pox by Mosquitoes.

The following results of a series of experiments carried out on " The Transmission of Fowl-pox
by Mosquitoes " by Robert Matheson, E. L. Brunett and A. L. Brody of the N. Y. State Agricultural
and Veterinary Colleges, Ithaca, N. Y., and published in the Poultry Science, Vol. X, No. 5 of July
1,1931, are of interest, viz.:—

1. Transmission of fowl-pox by mosquitoes (Aedes vexans Meigon) was demonstrated.

2. Bollinger bodies were found in the enlarged cells met with in lesions of the disease.

3. Fowl-pox was transmitted 2, 3, 9, 16, 17 and 27 days after the mosquitoes had fed on fowl-pox
comb lesions.

4. Transmission occurred 3 and 9 days after feeding mosquitoes on raisins contaminated with
fowl-pox virus.

5. Fowl-pox developed 11 days after inoculating the comb with a suspension of crushed mosqui-
toes which had fed on raisins contaminated with fowl-pox virus 27 days previously.

6. In two experiments the same mosquitoes were used, producing inoculations 2 and 27 days after
their infective meal. Between the inoculating experiments the mosquitoes were fed entirely on moist
raisins.

As is pointed out in the article and in a foot-note thereto, these observations confirm the conclu-
sions of other workers, including Blance and Caminopetros (C. R. Acad. Sci. France, Vol. 190, pp.
954-956, June 1930), who succeeded in transmitting fowl-pox by means of Culex pipiens as late as
58 days after feeding on infected birds and concluded that this mosquito could transmit the disease to
susceptible birds as long as they lived and could transmit pox of pigeons for at least 38 days after an
infective meal. [A. O.]

Zoologische Beitrage zum Surraproblem. XXI. Weitere Surraubertragungs-
versuche mit Tabanus striatus Fabr. und T. rubidus Wied. [ Further surra trans-
mission' experiments with T. striatus and T. rubidus.] Nieschulz, Otto. Arch.
Protistenk 65 (1-2) : 78-96. 1 fig. 1929.

In 77 experiments at the Buitenzorg state veterinary institute, 3730 specimens of Tabanus
striatus and T. rubidus were used in transmitting surra from carrier horses to infective experimental
horses, guinea pigs, and apes. In the case of surra carriers with the more severe infections the follow-
ing transmission capacities were obtained : with T. striatus, in direct transmissions, 1 :2.1 (29 flies) ;
after one-half hour interval, 1 : 125 (50 flies); after one hour, 1: 33 (100 flies); after three hours, 1 :
911 (911 flies); after six hours, 0: 1000; after twenty-four hours, 0 : 1100. With T. rubidus (includ-
ing earlier experiments), in direct transmission, 1 : 1.7 (24 flies) ; after one-half hour interval, 1 : 8
(144 flies); after one hour interval, 1 : 25 (50 flies) ; after three hours, 1 :100 (285 flies) and after six
hours, 1 : 1000. Transmission to several experimental animals one after the other succeeded very easily,
to three animals with one specimen ; with T. striatus even to four animals. T. rubidus is apparently
a better transmitter than T. striatus There exists therefore possibly a difference in the transmission
capacities of even closely related species. However, differences are relatively slight and more clearly
noticeable only at the longer intervals.— O . Nieschulz (trausl. by J. W. Scott). [ Reprinted from
the Biological Abstracts, 5, 3, March 1931.]

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