[QUOTE=SquishTheBunny;6780709]
Houndhill - thats fine. Not something I would be comfortable doing (but I dont have large breeds who are prone to osteosarcomas). I also lost a dog who had an ovarian tumor that had metastasized before the ovary couldbe removed. She was a small breed dog. Im sure you can understand the risks to both sides of the story.
Do you know what the stats are on intact females and osteosarcomas? I know that in Rotties there is a higher chance of developing it when spayed/neutered before age 1. The two we diagnosed last week were both intact females (One was a chessie, the other a standard poodle) I thought it was fairly rare. Both these dogs have had litters before but Im not sure of how recently. I am unsure the age of the poodle but the chessie is only 5. Also, a golden we CT’d a few months ago was an intact female, but only 8 months old. She had osteosarcoma on her rib.
Im not against keeping intact animals at all, just curious.[/QUOTE]
Oh, I am so sorry to learn of these cases, especially sad is the 8 month old. I had known of a 9 month old intact greyhound bitch with osteosarcoma in a front leg, but how sad for the pup.
Here is what I found as far as references on wikipedia:
As with any surgical procedure, immediate complications of neutering include the usualanestheticandsurgicalcomplications, such as bleeding and infection. These risks are relatively low in routine spaying and neutering; however, they may be increased for some animals due to other pre-existing health factors. In one study the risk of anesthetic-related death (not limited to neutering procedures) was estimated at 0.05% for healthy dogs and 0.11% for healthy cats. The risk for sick dogs and cats were 1.33% and 1.40% respectively.[6]
Spaying and neutering cats may increase the risk ofobesity.[7]In cats, a decrease in sex hormone levels seems to be associated with an increase in food intake.[8]In dogs, the effects of neutering as a risk factor for obesity vary between breeds.[9]
Neutered dogs of both sexes are at a twofold excess risk to developosteosarcomaas compared to intact dogs. The risk of osteosarcoma increases with increasing breed size and especially height.[10][11][12]
Studies of cardiac tumors in dogs showed that there was a 5 times greater risk ofhemangiosarcoma, one of the three most common cancers in dogs, in spayed females than intact females and a 2.4 times greater risk of hemangiosarcoma in neutered dogs as compared to intact males.[13][14]
Spaying and neutering is associated with an increase in urinary tract cancers in dogs.[15]
Neutered dogs of both sexes have a 27% to 38% increased risk of adverse reactions to vaccinations. However, the incidence of adverse reactions for neutered and intact dogs combined is only 0.32%.[16]
Neutered dogs have also been known to develop hormone-responsivealopecia(hair loss).[17]
A 2004 study found that spayed and neutered dogs had a higher incidence of cranial cruciate ligament (CCL) rupture, a form of anterior cruciate ligament (ACL) injury.[18][clarification needed]
[edit]Specific to males
About 2% of neuteredmale dogseventually developprostate cancer, compared to less than 0.6% of intact males.[19][20]The evidence is most conclusive forBouviers.[21]
In a study of 29 intact male dogs and 47 castrated males aged 11–14, the neutered males were significantly more likely to progress from one geriatric cognitive impairment condition (out of the four conditions – disorientation in the house or outdoors, changes in social interactions with human family members, loss of house training, and changes in the sleep-wake cycle) to two or more conditions. Testosterone in intact males is thought to slow the progression of cognitive impairment, at least in dogs that already have mild impairment.[22]
As compared to intact males, male neutered cats are at an increased risk for certain problems associated withfeline lower urinary tract disease, including the presence ofstonesor a plug in theurethraand urethral blockage.[23]
Neutering also has been associated with an increased likelihood of urethral sphincter incontinence in males.[24]
[edit]Specific to females
There is some weak evidence that spaying can increase the risk ofurinary incontinencein dogs, especially when done before the age of three months. Up till 12 months of age, the risk decreases as the age at spaying increases.[25]
Spayed female dogs are at an increased risk ofhypothyroidism.[26]
[edit]Current research
Various studies of the effects neutering has overall on male and female dog aggression have been unable to arrive at a consensus. A possible reason for this according to one study is changes toother factorshave more of an effect than neutering.[27]*One study reported results of aggression towards familiar and strange people and other dogs reduced between 10 and 60 percent of cases,[28]*while other studies reported increases in possessive aggression[29]*and aggression towards familiar and strange people,[30]*and yet another study reported no effect on territorial aggression, and only a reduction in dominance aggression that existed for at least 5 years.[31]*For females with existing aggression, many studies reported increases in aggressive behavior[32][33][34][35]*and some found increased separation anxiety behavior.[30][36]*A report from the American Kennel Club Canine Health Foundation reported significantly more behavioral problems in castrated dogs. The most commonly observed behavioral problem in spayed females was fearful behavior and the most common problem in males was aggression.[37]*Early age gonadectomy is associated with an increased incidence of noise phobias and undesirable sexual behaviors.[38]
^Priester; McKay, FW (1980).“The Occurrence of Tumors in Domestic Animals”.National Cancer Institute monograph23(54): 1–210.PMC1790092.PMID7254313.
^Ru, G; Terracini, B; Glickman, L (1998). “Host related risk factors for canine osteosarcoma”.The Veterinary Journal156(1): 31–9.doi:10.1016/S1090-0233(98)80059-2.PMID9691849.
^Cooley, D. M., Beranek, B. C. et al. (1 November 2002).“Endogenous gonadal hormone exposure and bone sarcoma risk”.Cancer Epidemiol Biomarkers Prev11(11): 1434–40.PMID12433723.
