This sounded to me like 'carallo' even after listening to it several times slow and normal speed, and even when looking at the written word!! So , no, I don5 think the pronunciation has improved. Well not to my ear.
Either of the following translations into english IS correct ie. an horse or a horse, the former being most commonly used. Please note Duolingo that BOTH are grammatically correct so the 'typo' you refer to is incorrect. Thanks.