Worried about my girl

[mittens1997]

Dakota is going in for spay on Friday.

She's a year and a half and has just finished her second heat cycle.
She hasn't been spayed until now because she was in the field "guarding" animals, and we were going to breed her and raise the pups up as trained livestock guard dogs, since there are none in our area, and a high demand, and most farmers are ordering them in from other provinces. Anyways, she was a awful guard dog (afraid of her own shadow!) so we took her out and she is now a companion,

not wanting unneeded puppies, we are taking her to be spayed. I read something about Mammary gland tumor being common in dogs after spay. I'm seriously worried and concerned. Can i do anything to help her or prevent it? What is the precentage? has your dog been spayed after heart cycles and been mine? Has your dog had this cancer?

Please just give me help D: