軍犬 is read as ぐんけん (gunken) and means war dog.
ぐんけん
gunken
ぐんようけん
war dog
ぐんぴょう
armed forces
ぐんじ
military affairs
ぐんじん
military personnel
ぐん
military authorities
ぐんび
armaments
ぐんこう
naval port
ぐんぶ
ぐんき
military aircraft
ぐんよう
for military use
ぐんせい
government affairs relating to the military
いくさ
troops