Hi,
Congratulations on your new furry addition!
Your vet would have to do an in-person exam and pre-op bloodwork, to make sure he's in good physical health, and you can discuss the neuter surgery with the doctor at that time. If he's healthy, there shouldn't be a problem. If the vet advises against surgery at his age, due to some underlying or potential problems, then he won't be neutered.
No, he will not exhibit the same type of aggression towards female dogs in heat, as he shows now, but both neutered and unneutered dogs usually do show interest in females in heat, even though the neutered male can't act upon his 'interest' in the female.
"When castration is being considered for an older dog, the benefits must be weighed against any risks associated with anesthetic and surgery. Since castration surgery is seldom associated with any complications, it is the anesthetic that is the primary concern. If castration is being considered as a separate procedure for a medical reason (prostatic enlargement, testicular tumors, perianal tumors), then there is a significant benefit to the dog’s health, comfort and perhaps longevity, in having the castration performed. If the dog is exhibiting any undesirable behaviors that might be improved by castration (roaming, masturbation, mounting, interdog aggression, excessive sexual interest or marking), there may also be a significant benefit to be gained from castration. Although not infallible, a physical examination, a series of blood and urine tests and any additional screening that your veterinarian may feel is warranted for your dog (e.g. EKG, chest radiographs), can help to determine if your pet has any significant anesthetic risks. These tests can also help the veterinarian determine which anesthetic protocol would be safest for your pet. Since many older pets require anesthesia for other procedures (e.g. growth removal, preventive dentistry), the benefits can often be further increased, and the number of anesthetic procedures reduced by performing the castration along with the other procedure." (From:
http://www.sniksnak.com/doghealth/neutering.html)
I hope everything goes well.
Cher
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