A retrospective study examined the prevalence and risk of various autoimmune diseases for both intact and castrated bitches. Six of the autoimmune diseases examined had a significantly higher prevalence in neutered dogs than in intact dogs. These results underline the importance of dog owners being informed about the advantages and disadvantages of castration and possible side effects by their veterinarian prior to castration.
The effects of castration on the risk of autoimmune diseases: a retrospective study, CR Sundburg et al. BMC Veterinary Research 2016
Castration is one of the most common procedures performed on dogs in the United States. It has been shown that castration can reduce the risk of some diseases. Based on current study results, however, an increased risk of certain structural diseases and types of neoplasia in connection with castration can be assumed. The influence of castration on the development of autoimmune diseases has not yet been investigated.
The study examined the prevalence and risk of various autoimmune diseases for both intact and castrated bitches.
Material und Method
90090 dogs (patient data from the University of California / Davis, 1995-2010) with one of the following diseases were included in this retrospectively evaluated study:
Atopic dermatitis, autoimmune hemolytic anemia, canine myasthenia gravis, colitis, hypoadrenocorticism, hypothyroidism, immune-mediated polyarthritis, immune-mediated thrombocytopenia, inflammatory bowel disease, lupus erythematosus, pemphigus complex.
In contrast to intact dogs, neutered dogs had a significantly higher risk of developing one of the following autoimmune diseases:
Atopic dermatitis, autoimmune hemolytic anemia, hypoadrenocorticism, hypothyroidism, immune mediated thrombocytopenia, inflammatory bowel disease. In autoimmune hemolytic anemia and hypoadrenocorticism, the risk was greater for male animals than for female animals.
Six of the autoimmune diseases examined had a significantly higher prevalence in neutered animals. This underlines the important role of sex steroids in the context of immune regulation. Castration is of crucial importance for population control and the prophylaxis of diseases of the reproductive organs and offers the dog owners a possibility for a more comfortable coexistence with their animal. Despite the advantages, the results of this study suggest that castration can increase the risk of developing an autoimmune disease.
The results underline the importance of dog owners being informed about the advantages and disadvantages of castration and possible side effects by their veterinarian prior to castration.
Original study: Sundburg et al. Gonadectomy effects on the risk of immune disorders in the dog: a retrospective study. BMC Veterinary Research (2016) 12: 278.
German summary of the study: Dr. Gerda Bäumer. Prevalence and risk of autoimmune diseases in castrated dogs. The Practical Veterinarian 98, Issue 2 (2017).