11221
A total of 576 1 - day - old Ross broiler chicks were housed in six treatment groups [ six replicates of 16 each ; control , CLI ( 15 g kg ( - 1 ) diet ) , 50 parts per billion ( ppb ) AF , 50 ppb AF plus CLI , 100 ppb AF , 100 ppb AF plus CLI ] for 42 days .
 AF, AF, AF, AF
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 AF, AF, AF, AF