Loose manure in pregnant mare

Question
Hello,

In middle January I bought a 13 year old mare. She has had one foal that I know of. We were told that she was not bred back, but guess what. She will be having a foal early summer of this year. The last owner did not properly take care of her. He didn't take care of her hooves for months, she was not being dewormed, she was covered in Bott eggs, and was underweight. I immediately took care of all that. But from the first day that I got her, her manuare has been very loose, almost like cow patties. Every now and then it would be normal but it was rare. But today I noticed as I was cleaning her stall (more like a run-in though) that it turned in to more of a pancake look rather than the cow pattie. She is dewormed every month and I use a diff. dewormer every month and my vet said it was good with him, and her fecal came back negative. I feed her Safe Choice and grass hay twice a day, and plenty of fresh water. So my question is, is it normal/common for a pregnant mare to have such loose manure for so long? Or should I bring her back to my vet for more tests to be done?

Thank you

Answer
Hi Brittany,
                This does not sound normal and raises some red flags. I would get some more tests done. There are several things that could be happening. She could have chronic Salmonella infection. Have the Vet do a PCR test. Have the Vet also test for carbohydrates digestive problems. She may have problems with digesting her food.  I would also check for sand in her manure and give her a cup of plain yogurt each day and feed her a pelleted feed. This will help her with her. You might also want to put some electrolytes in her water just in case she is losing them through her manure.

Please let me know what happens.

Lisa