78 REPORT OF THE AGRICULTURAL RESEARCH 



Ratin is a bacterial culture prepared in Copen- 

 hagen, which is intended to produce an infec- 

 tious disease in rats which have fed on baits 

 treated with it, and which then spread the con- 

 tagion amongst others. Although the cultures 

 when received at Pusa were alive, as was proved 

 by transfers, no pathogenic effects followed 

 when given with food to captive rats. In cor- 

 responding with the Director of the Ratin La- 

 boratory at Copenhagen I suggested that the 

 virulence of the cultures might be regained by 

 cultural methods in India. 



Trofe Ratin is not a bacterial cailture but 

 a vegetable poison, the principal feature of 

 which is its toxicity for rats and mice and 

 harmlessness for other animals. Experiments 

 proved that its efficacy in India depends upon 

 its use within a limited period of time after its 

 preparation, as rapid deterioration takes place 

 with loss of toxicity. Its cost precludes any 

 possibility of use on a large scale by cultivators, 

 but might allow of employment in special cases, 

 such as in granaries or warehouses. 



4. A disease of Tnsmr silkworms at Chaibassa was 



investigated and a report submitted to the 

 Director of Agriculture in Bengal. The general 

 conclusion arrived at was that death was due 

 to bacterial invasion of the alimentary canal, 

 but that as the extent to which this developed 

 was dependent on unsuitable diet consequent 

 principally on climatic causes, it would be im- 

 practicable to apply preventive or remedial 

 measures. 



5. A scheme for bacterioloo'ical work in connection 



with the proposed dairy at Pusa was elaborat- 

 ed, including the idea of a course of training 

 for students in Bacteriology as applied to 

 dairy work. 



