Dominance behaviour between two female Shepherds, spayed

Question
We recently lost our 6 yr old male neutered Shepherd. When he was 4 yrs old we adopted a 6 1/2 wk old female Shepherd. They played very well and after we lost him in Aug 2009, we decided to rescue a female Shepherd (1 yr 2 months old). The older female and the new female got along for the first few months, however, in the past two months, there have been dominance issues, with the older one humping the younger one.
Two wks ago the older female became quite dominant with the newer dog and it led to the older one getting a serious bite in the hind leg, which led to an infection in need of antibiotics.
We need to know how to work with the dogs so they can co-exist in harmony.
Thank you for your assistance.

Answer
Hi Catherine,

Having two female dogs is often more problematic than having a male and a female, or two male dogs at the same time. Spaying them both can be helpful, but that isn't always the case.

Your problem sounds like professional help is needed. Contact your vet or local boarding kennel to get a referral for a dog behaviorist/trainer in your area.

Until you can get a handle on this aggression issue, you should separate your two dogs during meal times and when you're not home, walk the dogs individually, and take away objects such as bones or rawhides that cause conflict. Don't put your dogs in situations where competition may lead to aggression. It might be helpful to keep the more aggressive dog on her leash while she's in the house. Either tie the end of her leash to your belt loop, or keep it around your wrist. The moment your dog looks at the other dog, give the leash a tug, and make her sit (or whatever command shes knows). When she complies, praise and reward her. This will help enforce your role as the leader who must be obeyed.

It is essential that steps be taken to prevent any subsequent injuries to your other dog. Prevention is an essential part of the process because every fight is a huge setback that only makes the problem worse and harder to change. You might consider keeping a basket style wire muzzle on the more aggressive dog. This is a very humane style of muzzle, it allows the dog to pant, and to drink.

Best of luck,

Patti