I thought I'd add that, I have read of instances of burgess nuggets causing mushy cecotrope issues for some rabbits. Might be due to the higher grain and lower fiber. Not necessarily the case here with your rabbits though. For their size, your rabbits really are getting a pretty minimal amount. But just something to keep in mind, as any rabbit can have potential food sensitivities.
This didn't end up being a problem with the burgess in the thread below, but a good discussion on how the owner was able to figure out the cause of their rabbits mushy poop issue, which ended up being parasites, coccidia and pinworms.
https://www.rabbitsonline.net/threads/help-is-this-mushy-night-poop-or-diarrhea.93108/
And in this discussion, it was a feed/sugar sensitivity causing issues. Which I've had a few rabbits like this. One especially who couldn't tolerate even the slightest amount of any sugars or pellets in his diet.
Rabbit with runny cecotropes
This didn't end up being a problem with the burgess in the thread below, but a good discussion on how the owner was able to figure out the cause of their rabbits mushy poop issue, which ended up being parasites, coccidia and pinworms.
https://www.rabbitsonline.net/threads/help-is-this-mushy-night-poop-or-diarrhea.93108/
And in this discussion, it was a feed/sugar sensitivity causing issues. Which I've had a few rabbits like this. One especially who couldn't tolerate even the slightest amount of any sugars or pellets in his diet.
Rabbit with runny cecotropes