Hi

I have a 5 year old gsd dog and a 15mth old gsd dog,both entire, For the last few days my eldest has been paying a great deal if attention to the younges rear. He constantly seems to have his nose stuck underneat the tail of the youngster.

I thought to begin with worms so wormed him last week. This hasnt made a pick of difference.

Could anyone explain this bizzar behaviour
thanks

Would suspect some minor problem, may be a damage small blood vessel, or over full anal glands.