I worm my flocks before a super cold spell because working them can make them sick a little bit. Then id ck the bird for external parasites to rule them out. The can kill just as easy in a harsh winter as this. If not perhaps internal parasites then. I do worm yr around - however its not good to do so in this harsh weather. Normal winters i have gotten away with it- not this one. Try to use damacious earth for both internal and external parasite it should help and cant hurt! I use it more in the winter in between the winter and spring.
Leeann
Leeann