possible inbreeding

Question
QUESTION: i have two labs at home 2yrs old brother and sister and we think that the girl might be pregnant. shes never been very active but it seems worse and she seems more needy than usual. i know that theres the possibility of false but could she also be pregnant?

ANSWER: Hi Kim

When you have siblings in the house, one should be fixed.  The possibility of pregnancy is very real however doing an interbreeding will bring out every possible trait that exists in the lines.

---------- FOLLOW-UP ----------

QUESTION: to go back to what was said someone once told me that you could give a dog a pregnancy test and it would work just like it would on a human. would that work and could i do that to my dog to be positive on whether she was pregnant?

Answer
If that works that would be truly amazing as they are two different species.  And also a bit amazing is that the canine reproductive cycle is hormonally the same when they are pregnant or not.

What WILL work, is x-rays at 50 plus days, ultra sound, after 25 days or a blood test that will detect relaxin, a hormone that is produced in pregnant dogs but is not found in non-pregnant dogs, done after 30 days.