darkened spots on both side of female

[lightningstrikes]

I have a wonderful 5 year old bitch who has my stamp of approval and my family as well since my wife and son have now taken her from me lol. I bred her to and I noticed almost imedietly after the breeding took place and I don't know if they were there prior to the breeding which I don't think they were on both side of her rite by her rump before her back legs are two darkened spots almost identical in shape color and places just opposite sides never seen it before she has whelped me pups before just curious if any of u have ever experienced this ?? .... and thank you u again in advance

Y.I.S. Lightningstrikes