Loose Droppings - HELP!

I have an ISA brown chicken (Bridgette) who free ranges in my back yard with my little white Silkie Lola. Bridgette has started having loose droppings, not quite diarrhoea and is making quite a mess of her sleeping/nesting area.

It all started after she ate some kitchen scraps that had a small amount of tuna in it, and possibly some mayonnaise although I washed most of it off. Lola ate that as well, but she seems fine.

They are fed on laying pellet complete feed and mixed seeds with some bird grit (which they don't really like), but I also throw them some kitchen scraps to keep things interesting (they LOVE chic peas, sweet potato, and corn). They nibble on quite a lot of grass as well, so they are getting their greens although they don't like green kitchen scraps.

Neither chook has laid an egg yet, but I am sure they are getting close. Lola is low to the ground and is fussing a bit (making frustrated sounding squeaks) and Bridgette is crouching when we go near her which I understand is her way of presenting herself to the rooster (me!).

Can you advise if I should be worried about the loose droppings, and if there is anything I could be doing better to keep these little gals healthy!

I am a bit of a worrier as I have lost quite a few chickens in the last few months. The first went to an eye infection after some rice hull got stuck in her eye; another was a rooster and our council won't allow that, the next was very young and just didn't make it, the latest was the last of my little black silkies Pip and she had an egg laying malfunction and couldn't be saved :-( Lola and Bridgette are doing SO well, but I just don't want anything bad to happen!!

Thanks for the advice Jazkabor, is there any special kind of probiotic I should use?

Yogurt is full of probiotics and chickens love it so you can always try that as well.

I heard from same source, to keep it light when feeding dairy. I'd google it before I fed too much. Our leader has a farm and buys it ( pribiotic) at the feed store in big bags she was sweet and sent us home with a baggy.. I don't trust store yogurt to provide it though, you could crush up some tablets from the grocery or health store... May be a lot more budget friendly for two pet hens.

She also sprinkles garlic on their food. She does all the things I mentioned all the time for continual health. I feel like I am forgetting one..... I'll let you know if I remember.