I have become aware of some breeders breeding brother and sister, father and daughter etc and was wondering whether firstly this is something which is generally acceptable. I understand it can improve the lines but i also thought this causes birth defects etc so i was confused?

I would not breed with them being so close, as agree to possible defects in the kittens,

I would not do this.

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best purrs

Ra

http://www.bobergsiamese.co.uk/

I would definitely not do it purposefully either, its just asking for trouble. Most breeders 'line breed' ie double up on a particular cat in a pedigree, to cement a particular good point/type in the offspring, but even that should be done with care as you have to be completely sure that the line you are doubling up on is free from any genetic anomalies - which is almost an impossible thing to ascertain as you could have recessive nasties hidden being passed unseen from generation to generation just waiting to be doubled up on.

Sorry 'Soap Box Alert'

If close family members are deliberately bred the chances of getting problems is enhanced greatly. I have seen breeders do it and proclaim their lines are fine because they had no birth defects or dead kittens, but there is no way of telling at that point, even at 14 weeks when they leave home, what inherent weaknesses you have bred into those kittens, cancers, heart problems, kidney or liver problems, all these things could come out later in life and cause not only suffering for the cat, but heartache for their family. Its illegal for people to marry close relatives for a reason.

In my last litter my cats dad was the stud cats grandad.
I lost one kitten at 2 days with a cleft palate. I felt awfull for the kitten that suffered, especially knowing it could have been avoided.
Definatly a lesson learnt the hard way!

I'm being stupid here but what is the difference then when people line breed?

Line breeding means breeding cats that share common ancestors but are not closely related. Its still inbreeding to an extent, just a lesser evil but should still be done with care. If you line breed with one generation ideally you should outcross completely for the next.

There is no differenceits something thats always been done with dogs and cats,i cant understand it either!especially when breeders look down at un registered breeders and claim they could be breeding close kin!its something that works for some but not for others.

I have done both father-daughter and brother-sister without any problems. I agree you need to be careful.

I am trying to avoid it completely.

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