Determination of the silkworm (Bombyx mori L.) heat requirements in rearing room of village house for optimal environmental conditions

Aim of this study was to determine heat requirement for silkworm larval period of 27 days to ensure optimal environmental conditions in the rearing room in april and may. firstly,when silkworm rearing started on april 20,it was determined that rearing room should be heated during the larval period. during this period,heat requirements of silkworm 1st,2nd,3rd,4th and 5th instar stages were 2036.38,1851.25,1666.13,647.94 and 1796.79 w/h,respectively. secondly,when the rearing started on april 27,heat requirements of 1st,2nd,3rd,4th and 5th instar stages were 2036.38,1018.19,833.36,647.94 and 1796.79 w/h,respectively. thirdly,when it started on may 1,heat requirements of 1st,2nd,3rd,4th and 5th instar stages were 1203.31,1018.19,833.06,647.94 and 1796.79 w/h,respectively. when rearing started on may 1,the heat requirement of the 1st instar stage was 40.9% less than that of april 20 and april 27. as silkworm released urine,the heat requirement of the 5th instar stage was higher than that of other periods. as a result,keeping in view the heat requirements and the development the of mulberry leaves,the rearing starting on may 1 was found to be the most suitable period compared to other two rearing periods. copyright 2016 zoological society of pakistan.