"The certificates for the mixed and rabies vaccines for dogs is valid for 1 year."
"The certificates for the mixed and rabies vaccines for dogs is valid for 1 year."
"the certificates for ~" 「〜証明書」
"the mixed and rabies vaccines" 「混合ワクチンと狂犬病ワクチン」"the mixed vaccine and rabies vaccine" も言えます。
"for dogs" 「犬の」
"is valid for 1 year" 「有効期限1年以内」