鶏痘 is read as けいとう (keitou) and means fowl pox.
けいとう
keitou
にわとり
chicken meat
とり
bird
とりにく
けいらん
hen's egg
けいこうぎゅうご
better to be the beak of a rooster than the rump of a bull
にわとりごや
henhouse
しゅとう
smallpox vaccination
てんねんとう
smallpox
はっとう
outbreak (of pox)
すいとう
chickenpox
ようけい
poultry raising
じんとうしゅとうほう
variolation