Page 1224 - Veterinary Immunology, 10th Edition

VetBooks.ir Autoimmune Reproductive Diseases

If the testes are damaged so that hidden antigens are released, an
autoimmune response may cause orchitis. Experimentally,

autoimmune orchitis may be produced in male animals by injection
of testicular extracts emulsified in Freund's complete adjuvant.
Autoantibodies to sperm may also be detected in some animals
following injury to the testes or long-standing obstruction of the
seminiferous ducts. For example, dogs infected with Brucella canis

have chronic epididymitis and become sensitized by sperm
antigens carried to the circulation after phagocytosis by
macrophages. These sperm antigens stimulate the production of

IgG or IgA autoantibodies. The autoantibodies can agglutinate and
immobilize sperm, causing infertility.
In stallions and cows, antisperm autoantibodies may be
associated with reduced fertility or infertility. In certain lines of
black mink, 20% to 30% of older males are infertile as a result of

high levels of antisperm antibodies. The animals have a monocytic
orchitis, and immune complexes are deposited along the basal
lamina of the seminiferous tubules.

Dermatologists recognize an autoimmune dermatitis in which
intact female dogs develop a hypersensitivity to endogenous
progesterone or estrogen. The disease presents as a bilaterally
symmetrical intense pruritus, erythema, and papular eruption. Its
development usually coincides with estrus or pseudopregnancy.

Corticosteroid treatment may have little effect, but testosterone may
help.
Many vaccine companies are interested in production-enhancing

vaccines. These vaccines commonly interfere with normal hormone
production or reproductive behavior by inducing an autoimmune
response. Thus a vaccine designed to neutralize production of
gonadotropin-releasing hormone effectively lowers testosterone
levels. This results in improved meat quality, faster growth, and

reduced aggression by bulls. This vaccine is also used to reduce
aggressive behavior in male pigs and block the production of
androstenone, the lipophilic steroid that contributes to boar taint,

the offensive odor associated with cooked boar meat. In horses, a

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