ABSTRACTS

Excretion of Streptococcus pyogenes in the milk of naturally infected cows.
BENDIXEN, H. C. and MINETT, F. C. (1938). (Journal of Hygiene Camb. 38,
374-383.)

THE authors record observations on two cows known to be responsible for out-
breaks of tonsilitis or scarlet fever due to excretion of Str. pyogenes in the milk. In
the case of one cow (M. 36), no marked clinical manifestations of mastitis were noticed,
but the milk from the affected quarter (L. F.) was altered and Streptococci in almost
pure cultures were recovered from the milk for a period of about thirteen months
including a dry period of three months. The other quarters remained unaffected.
Experimental infection into the teat canal of another cow with culture from the
L. F. quarter set up clinical mastitis. The animal was subsequently killed and
histo-pathological examination of the affected tissue revealed chronic inflammation.

The second cow had a previous history of injury to the R. F. teat resulting in
clinical mastitis of both the fore-quarters. Haemolytic streptococci which proved
fatal to mice, were isolated from milk samples of affected quarters, in this case the
duration of excretion of Str. pyogenes was not more than six weeks.

The importance of injuries to the teats in the spread of mastitis is emphasized.
(J. A. I.).

Studies on the microbiology of the caecum of the horse. F. BAKER,
and R. MARTIN (1939). (Zeutralblatt Bakteriologie, Parasitenkunde und Infektion-
krankheiten, Bd. 99 pp. 400-424.)

THE authors in this article have paid particular attention to the features which
attend the disintegration of cell-wall substances. Changes taking place in slitu were
observed by direct microscopical examination of the caecal material fixed in 10 per cent
formalin. Along with this polariscopic and microchemical methods were employed
by means of which it has been possible for them to establish, with considerable amount of
precision, not only the nature and extent of disintegration taking place, but also the
characteristics of the micro-organisms by which it is effected. Prevalence of iodophile
microflora and fauna and the significance of this feature have been discussed in relation
to the synthesis and degradation of carbohydrates in the caecum. The authors claim
that in the caecum of the horse, the presence of functional activity of protozoa is far
more prominent than in either the guinea-pig or the rabbit.

It has been demonstrated that the cyto clastic process is brought about by the action
of iodophile mirco-organisms exercised in situ. The processes involved in the disinteg-
ration of the components of cellulose and hemicellulose, as evidenced by polariscopic
method and microchemical and staining reactions, are described in some detail. Two
phases in the destruction of the optically birefringent polysaccharides have been noticed.
In the first phase of reaction, the colour reactions with chlorzinciodine and staining with

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