7151
Gross observation and histological analysis of the amputated heart at 21 days postamputation revealed that TCDD - exposed fish had not progressed beyond the initial clot formation stage , whereas the vehicle control fish showed substantial recovery and almost complete resolution of the formed clot .
 Chemical: TCDD
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: TCDD