370 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [II, IV

cases of rinderpest closely follows the variations in weather, the epidemics closely
being connected with the inclement seasons of the year. Often a weakling in a
herd starts an epidemic. It apparently takes a weak strain of the organism which
the stronger cattle can resist and converts it into a virulent strain too strong
for even the robust cattle."

Curasson [1926] was able to associate the presence of healed ulcers in the
abomasum, patches of congestion in the intestine and moist and enlarged mesen-
teric lymphatic glands with animals which after recovery from rinderpest showed
persistent poorness of condition, dull coat, frequent cough, intermittent fever, chrome
enteritis and in females, chronic vaginitis and sterility. Further he was able to
infect a susceptible calf with such abomasum in one out of two cases, the positive
result being obtained with the material collected 34 days after apparent recovery
and the negative result with that collected 7 weeks after recovery.

Several cases of the infectivity of materials other than abomasum from animals
suffering from chronic rinderpest are on record. For instance, Hutyra and Marek
[1916] showed that the blood of an animal chronically affected with rinderpest may
remain virulent up to 30 days. Curasson [1926] showed that in animal which
showed a second rise of temperature one month after recovery, the blood was
infective by both subcutaneous and intravenous route. Delpi [1928, 1930] showed
that in animals suffering from atypical rinderpest—a disease characterised by a
prolonged duration of over one and a half month—the blood was infective through
the entire period and at the time of death. Curasson [1922, 1926] gave two in-
stances of the infectivity of the vaginal discharge from recovered animals one
month after recovery. Jacotot [1932] proved that in one instance the vaginal
discharge from an animal which had aborted 34 days after infection was infective,
although its blood had ceased to be infective by them. Curasson [1926] showed
that the faeces of a heifer which had recovered 7 weeks previously was infective
though duodenal ulcers taken 3 days later were found to be non-infective. He
stated that he had also known of a cow whose milk was found to be infective two
months after recovery from rinderpest.

The available evidence on the existence of carriers has been seen. Reports
purporting to show the truth of the contrary view have been recorded by several
workers. In a reference quoted earlier, Ward and collaborators [1914] stated
that they could not demonstrate the presence of carriers among recovered animals
by the method of housing susceptible and recovered animals together. Rupert
[1918], who stringently criticised Schern's work regarding the existence of carriers,
pointed out that Mrowka himself had been unable to infect susceptible cattle with
duodenal ulcers from his cases and recorded the result of his own work with Woefel
in which he found that as much as three litres of blood from a recovered beast