About a week ago while doing my barnyard chores Ebony my black bantum rooster was sparing with another rooster and after about 15 seconds he all of a sudden started flopping around on the ground. I immediately picked him up and he immediately died in my arms. I was shocked, no injuries, was it a heart attack? Today when I left the barn this morning all chicks were doing fine, eating and running around. I went back out to the barn about 3 hours later to gather eggs and check on everyone and laying there was BB (black beauty) on her side sort of gasping for air. I picked her up, checked her all over no injuries. She could not stand and started flopping around like Ebony. I checked her throat to see if she had food lodged but she didn't. She continued to get more stressed so after about fives minutes I put my baby to sleep. I couldn't let her suffer. What is happening to my Silky Bantums? Any help would be greatly appreciated. I love my chickens. Both chicks were less than two years old.