"Carla Polastro" <carlapolastro@libero.it> ha scritto nel messaggio
news:9crpnq$fcolj$1@ID-43598.news.dfncis.de...
> Le cose non sono così drastiche: la sterilizzazione prima del primo calore
è
> in assoluto la più efficace per quanto riguarda la riduzione nella
> possibilità di sviluppo di neoplasie mammarie (secondo studi americani,
fino
> al 60%). Ma anche la sterilizzazione dopo il primo calore, ma in giovane
> età, aiuta in questo senso.
>
> Carla

Questo è quanto risulta anche a me, solo la percentuale mi sembra bassa.
Ad integrazione e conferma:

"...spaying a female prior to 2-1/2 years significantly decreases risk for
both benign and malignant mammary tumors. Spaying after this time reduces
risk for benign tumors but appears to have no advantage for prevention of
malignant tumors."...

.."Spaying prior to the first or second heat period significantly reduces
the likelihood of mammary tumors. Spaying anytime up to 2.5 years of age
(but prior to five heats) will have some protective effect, but after 2.5
years of age, spaying is not effective in the prevention of mammary
tumors."...

.."Spaying a dog PRIOR to its first estrus (heat cycle) reduces its risk of
breast cancer by 99.5% as compared to an unspayed female dog. Spaying
between the first and second heat cycles reduces the risk by 92%, and
spaying after the second heat reduces the risk by 74%. Dogs spayed after 2.5
years of age have no decreased risk of breast cancer as compared to unspayed
females."....

Sono tratti da articoli facilmente rintracciabili con Google.

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