The invention is in the field of detection of infectious disease in general and micro-sporidian disease in silk moth in particular using automated photo-micrographic image capturing and data analysis technique. Micro-sporidian parasites, mainly Nosema bombycis cause a virulent and infectious disease that creates a huge loss in the silk industries. The objective of this project was to develop a photo-micrographic analysis solution to detect micro-sporidian spores (Pebrine) in the samples of silkworm/silk moth.

With this project, a new method using automated microscopic image analysis solution for micro-sporidian disease detection has been developed, using a low-cost digital camera positioned on the top of the
eye-piece of a customised low-cost student microscope.

Challenges

Until recently, there was a manual system in place for detection of infection in the insect. The technology mainly involved identification of Sporozoa through low-cost student microscope and elimination/destruction of eggs laid by infected female moths. This has several limitations—unless the concentration of spores in the microscopic field is sufficiently high, the disease may go unnoticed. The process of detection of spores under microscope was both time and labour consuming, as smears from individual moths were tested on one-on-one basis.

Only matured spores are clearly distinguishable in the microscope. Testing individual slide under microscope with small field of view was tedious and it needed a bulk testing, hence required a large pool of expert manpower.

Solution

The developed solution automates the Pebrine Spore Detection Process by capturing digital images from the microscope slide through USB camera mounted on top of the microscope and classifying Pebrine Spores within the captured images using digital image processing techniques thereby improving productivity and accuracy of this process.

Pebrine-O-Scope system follows the same sample preparation process. Slide is then treated with indegenous chemical treatment solution, which was developed under this project. This process helps removing the unwanted noise like fat bodies, tissue debries, bacteria etc. Automated image analysis software determines and locates the Pebrine Spores in the captured images by calculating its various dimensional and colour features.

Automated inspection methodology of Pebrine-O-Scope is simple enough to be used by an inexperienced user who does not know about Pebrine. The system is helpful to identify Pebrine Spore in fast, reliable manner.

The whole system has been interfaced with a computer via USB cable. An application has been developed to detect the spores automatically in the captured images using digital image analysis technique, thereby improving productivity and accuracy of this process.

Outcomes

The developed Pebrine-O-Scope Solution ensures disease free eggs to the silkworm rearers and thereby reduces the chances of crop failure due to disease. It completely removes the human error and drastically reduces the manpower requirement during the seed production cycle. The users of this technology are the Tasar seed producers in villages where silkworm rearers reside and supply the seed to the silkworm rearers.

The solution is beneficial to seed producers as well as cocoon producers in terms of income. Recently, C-DAC, Kolkata has handed over the technology of “Pebrine-O-Scope” solution to Tasar Development Foundation (TDF), a non-for-profit organisation involved in promoting Tasar Sericulture in Jharkhand, Bihar, West Bengal, Odisha and Andhra Pradesh.