How To Blast A Sequence Against Multiple Databases

Hello,

I have downloaded all the chromosome of Bos taurus and I have changed them in blast format using makeblastdb..and now I want to locally blast my sequence against these all chromosomes. now I have 29 databases. Is there any method by which I am able to blast my sequence against all 29 databases in my program.

What should I write in database????

@params = ('database' => '????????', 'outfile' => 'blast2.out', '_READMETHOD' => 'Blast', 'prog'=> 'blastn');

Thanks Manju Rawat