DNS TXT Record – Is It Safe to Add Additional Values?

In Dynamics 365 we need to be able to authenticate our domain for sending marketing emails. We have followed the advice in the Microsoft article below and now need to add the DNS records.

https://docs.microsoft.com/en-gb/dynamics365/marketing/mkt-settings-authenticate-domains#:~:text=all%20new%20instances.-,Authenticate%20a%20domain,of%20existing%20authenticated%20domains%20opens.

The TXT record it gives in the configuration is for the top level domain of our organisation. That is the one we want to authenticate. The thing is that our DNS already has a TXT record with the '@' symbol. I understand that this is a shortcut to the top level domain. If I were to add the additional value to that existing record of the key given in Dynamics 365, will that cause any issues? Is it safe to do that?

The text record already has values for SPF and some other keys.