SPF & DKIM records

Hi all

Sorry for the noob question, but as I’m a noob, here goes.

I’ve been asked to implement DMARC for our company.

I’ve created the DMARC record with p=none to get the reporting started.

We use a couple of 3rd party email services (Sparkpost & Taguchimail). I can see on our DNS that there are already SPF and DKIM records for these providers.

Do I still need to create my own SPF and DKIM records listing their sending IP’s or will the existing records suffice?

Cheers