68° Congresso Nazionale SCIVAC: Le domande più frequenti in ...

68° CONGRESSO NAZIONALE SCIVAC 11-13 Marzo 2011 - Milano
LE DOMANDE PIÙ FREQUENTI IN RIPRODUZIONE CANINA E FELINA
Tutto quello che i vostri clienti osano spesso chiedere e a cui voi non sapete rispondere
14 th EVSSAR Congress - Advances in Feline Reproduction - March 11 th 2011
versible but few data are available about side-effets of prolonged hyperprolactinemia.
Moreover, the cost would be prohibitive.
Anti-androgens including steroidal (cyproterone and chlormadinone acetate)
and non steroidal (flutamide and nilutamide) results in only a slight and
transient influence on spermatogenesis.
2. CHEMICAL CASTRATION
Chemical castration (intratesticular, intraepididymal or intra-vas deferens
injections) is another non surgical approach to male contraception.
The testicular tissue and testosterone production is preserved. We prevent
fertilization but not sexual behaviour.
The technique is quite easy to learn. The dog is sedated and a 22- gauge
1.25 cm needle necessary.
Differents compounds can be injected, one is commercially available in this
indication in US: zinc gluconate solution neutralized to pH 7 by arginine. Zinc
is considered to be non-mutagenic, non-carcinogenic and non-teratogenic.
The center of the testis is the target, injection is performed through the
cranio-dorsal portion of the testis. The volume of injection is related to the
testis size. Local side-effects reactions in the days after injection may occur,
necrotizing of the injection site is reported in less than 5% of cases (but can
be very severe).
Injection into the epididymis or vas-deferens is another option, much cheaper
(less volume) with an irreversible azoospermia in 90 days post-injection.
3. IMMUNOSTERILIZATION
Efforts have been made since decades to develop a vaccine that suppress
fertility in males. Several target of immunocontraception have been identified
some already efficient, other in expectation in the next decades.
Production of antibodies against GnRH include suppression of reproductive
behaviour, suppression of synthesis and secretion of gonadotrophins
and steroidal hormones, gonadal atrophy and the associated arrest of gametogenesis.
A GnRH vaccine was available in US until 2009. Testosterone decreased
following vaccination. No adverse events were observed after injection. Other
experimentally derived GnRH vaccines are developpped in dogs.
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