On our last walk this evening, Bella was picking up everything in her mouth. I've been able to keep her from picking up toads, although she doesn't "leave it" too well. Usually she chased them as they hop and barks at them, but I can pull her away before she can get a mouthful.
Tonight was different, it has been raining most of the day, and the toad are out in full force. She got hold of one and it puffed up in her mouth sliming her. She immediately began shaking her head and rubbing her mouth and chin in the grass. Here in FL we have the risk of an encounter with the Bufo marinus (Cane Toad) which can be deadly to dogs if licked. Not knowing for sure if this toad was a juvenile B. marinus (we have had several in the neighborhood) or the resident Southern Toad, I grabbe dBella with one hand, and the toad with another. The toad went into a bucket, Bella went into the sink.
Bella had her mouth washed out and washed out and washed out until there were no signs of slime left. She wanted to jump out of the sink soooo very bad. I was covered in water, she was covered in water, and the floor was covered in water - but it didn't matter to me - her first aid was my priority.

She was not very happy either way.
Luckily, General (our yorkie) had a similar encounter last year and we looked up the first aid for a Bufo encounter. Pretty much, rinse there mouth as much as possible without drowning the dog is the instruction, then watch them closely. Fortunately, after closer inspection, he toad was not a bufo, but was a southern toad.
Whew!