ABSTRACTS
Bovine virus enteritis (Winter dysentery). MACPHERSON, L. W. (1957).
Canadian J. Comp. Med. Vet. Sci., 21: 184-192.
The author has described a disease condition, viz., winter dysentery in bovines in
Canada, caused by a virus.
Epidemiological observations revealed that the immunity was transient and that there
was tendency to recurrent attacks particularly preceded by sudden drop in the atmospheric
temperature. Animals between 9 months to 9 years of age were susceptible. However, the
most severe symptoms occurred in animals of 1 to 3 years of age. The morbidity rate was high
while the mortality rate was only 1 to 2 per cent. The infection was found to be persuit on the
affected premises year after year.
Symptoms observed in the affected animals were naso-lacrymal discharge, slight rise
in body temperature, diarrhoea followed by dysentery, especially in young animals, and a
severe drop in milk yield. The course of the disease varied from 3 to 14 days depending on the
age of the animal.
Secondary bacterial infection by Actinomyces necrophorus or Corynebacterium pyogenes resul-
ting in buccal erosions, laminitis, bronchitis and peritonitis occurred in some young animals
4 to 8 weeks after the attack of the disease.
Hyperaemia of the mucous membranes of the abomasum and intestines and pete-
chiae on the mucous membranes of small and large intestines, enlargement of peyer's patches
and mesenteric lymph nodes and charactestic "zebra" markings on the mucous membrane of
the rectum were the common lesions observed on post mortem examination.
Experimental infection in bovines was effected by administration of filtrate or diluted
faecal matter from infected animals, sub-cutaneously or orally. Apart from the usual symptoms
of the disease, diphasic rise in body temperature and marked leucopoenia were observed
in the experimental animals. (P. S. B.).
Studies on fishmeal and the hatching rates of hens' eggs. R. COLES (1957).
J. Agri. Sci., 49: 95-99.
Although fishmeal is widely used in poultry rations, instances have been recorded on
depression in hatching rates when fishmeal is fed to breeding hens. In this experiment, samples
of white fishmeal from widely separated points of origin, U. K., South Africa, Iceland and
Canada, were employed. The birds in the four groups received a ration similar in every respect
with the exception that the 10 per cent fishmeal in each group was from one of the four
differing sources.
The fertility and the rate of laying showed no substantial differences between the birds
of the four groups. As regards the hatching rates of fertile eggs, two groups showed hatching
rates of 85.2 and 83.8 per cent, which were little above the level normally recorded in the
experimental flock. The third group was about 5 per cent below the figure of 80 previously
experienced in the flock while the fourth group showed an extremely poor hatching rate of
60 per cent.
Bacterial assays showed that only one sample contained aerobic spore-bearing bacteria
capable of coagulating yolk but the birds fed this sample manifested the mild depression
of 5 per cent in the hatching rate and this was the only group to show an appreciably above-
normal early death rate in the chicks. The hatching rate in all groups was, however, inversely
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