鼠族 is read as そぞく (sozoku) and means rodents.
そぞく
sozoku
ねず
mouse
みんぞく
people
かぞく
family
きぞく
noble
ぞく
(taxonomical) tribe
しんぞく
relative
しゅぞく
stellar population (i.e. population I, II and III)
ごうぞく
powerful family
いぞく
bereaved family
しぞく
clan
かくかぞく
nuclear family
ぶぞく
tribe