17664
Significantly high avidity levels were observed for anti - bothropic IgY antibodies on the 142nd day and for anti - crotalic antibodies on the 232nd day after the first immunization .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None