ABSTRACTS
183
III. The Speculum Method.—In this method sperm is collected with the speculum into a watch glass
and used as above. The method is useful if only a few ewes are to be inseminated.
IV. The Artificial Vagina Method.—This method gives the further advantage of dilution of sperm.
Good results have been obtained with the dilution fluid containing mucin in case of sheep, while for
cattle the dilution in peptone-lipoid solution proved successful. It is found that the sperm of a single
ram and bull was sufficient to inseminate 300 to 400 ewes and 1,250 cows respectively during one season.
The author points out that at present this method is chiefly employed for experimental purposes.
In a special glucose reagent at a temperature of 10-15° C. sperms are stored successfully for 18
days. [ B. S.]
Infectious sterility in the larger domesticated animals. EDWARDS, J. T. Proc.
Roy. Soc. Med. 26, 1192-1210, (1933).
Sterility has been classified under the following headings :—
I.—Genetic.
II.—Functional
III.—Infectious.
Endocrinal.
Nutritional.
(I) EQUINE STERILITY.
In the equine species a very high percentage of sterility is said to be associated with endometritis in
the female. The bacterial content of uterine secretions taken from 1 to 21 days post-partum have been
recorded as B. abortus equi, B. Coli, Diplo-streptococci, B. Viscosum equi, and a small percentage of
miscellaneous organisms. Most of these organisms have, however, been found as a normal vaginal
bacterial flora of mares. The relation of abortion to sterility according to the French records evidently
has little significance, because of the fact, that the incidence of sterility is no higher in mares that have
aborted than in those that have never aborted. It is rather striking to note that the proportion of cases
of sterility, in which bacteria from the uterine secretion have not been isolated, is very high. Evidence
tends to show that the bacterial infection has only a minor significance in equine sterility.
(2) BOVINE STERILITY.
Sterility in bulls.—The relative importance of the male as a factor in sterility is negligible, and the
average of sterile bulls is only about 1 in 150.
Apart from a small proportion due to other causes, such as congenital deformities and acquired
defects, tuberculosis of testicles and epididymis, and Br. abortus orchitis are also responsible for about
50 per cent. cases of sterility in bulls.
Sterility in cows.—On account of its prevalence and economic importance, the study of sterility
has of recent years attracted more attention, as it affects the cow more than any other kind of domesti-
cated animals. Infectious sterility in cows is caused by tuberculosis, contagious abortion, contagious
granular vaginitis and non-specific infection, and the diseases produced by these infections are cervicitis,
metritis, salpingitis, cystic-degeneration of ovaries and retained Corpus luteum.
The affection of organs of barren cows varies greatly in different countries according to the circum-
stances under which the animals are kept. The incidence of uterine diseases is very high among cows
kept indoors and fed on concentrated food stuffs for high milk production throughout the year. Ovarian
trouble is encountered mainly in underfed herds, bred out-of-doors. Cervicitis is common mostly among
cows, kept out-of-doors, pasture-fed and where calving is arranged to take place at the commencement
of the season of luxuriant vegetation.
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