PYOSEPTICAEMIA
OF
CALVES.
239
at Jehangirabad Cattle Farm, marked swelling of the glands of the head and
neck was noted. Pneumonia, chiefly of an apical type, is present in the majority
of cases. The affected animals resist all treatment and there is a tendency to natural
recovery, although a proportion of cases show a tendency to relapse. (Young
animals are more severely affected and the disease more protracted in them). The
youngest animal affected was 2 days old and the oldest 2 months and 17 days.
The calves had been reared under the most scrupulous conditions of hygiene and no
light could be brought to bear upon the source of infection. None of the cows
giving birth to the diseased calves showed any evidence of disease. A particular
examination was made of the udders and the milk of these cows. Bromthymol
blue tests performed at the farm upon freshly drawn samples of milk failed to detect
any evidence of either active or latent infection of the udder. There was no history
of abortion, retention of the placenta, or metritis of any degree in the cows of the
herd, which had also, over a period of years, remained singularly free from
mammary disease. It seemed impossible to elucidate any factor which might have
been considered of value in the determination of the pathogenesis.
PATHOLOGY.
Twelve calves were subjected to post-mortem examination. In younger
animals, the lesions were those of septicaemia. The spleen was slightly enlarged
and showed marked swelling of the malphigian bodies, and on mesial section of
the kidney, minute greyish white foci were present, chiefly in the cortical area.
Similar lesions were present in the liver. Theabomasum and duodenum were
affected, in some cases, with a severe haemorrhagic inflammation and in others
with a simple catarrhal inflammation with petechae in the mucous coat; swelling
of Payer's patches was observed and mesentric lymph glands were enlarged, suc-
culent and haemorrhagic. Areas of hepatization occurred in the middle and
anterior lobes of the lungs. A straw-coloured serofibrinous fluid distended the
pleural, pericardial, and in some cases the peritoneal sac. The pathological picture
presented in these acute cases was very similar to that of acute pasteurellosis of
calves. Older calves manifested little evidence of involvement of the gastro-
intestinal tract beyond a slight catarrhal inflammation and swelling of Payer's
patches. This type of case seemed to gradually merge into one in which the chief
lesion existed as a pleuropneumonia of rather a special type in which effusion and
early adhesions were prominent. The lung lesions consisted of primary apical
pneumonia, spreading posteriorly, usually bilateral in occurrence. An increase
in the volume of the interstitial stroma and the distension of the lymphatic spaces
with exudate had the effect of sharply delineating the outline of the lobules and
conferring on the tissue an appearance similar to that seen in chronic pulmonary
pasteurellosis. The lobules were severely hepatised, many of them necrotic and
in some this process had extended to actual abscess formation. Similar necrotic
foci with abscess production were encountered in the formative tissue at the angle