Bava Batra — Daf 35a

דרב אמר יחלוקו ושמואל אמר שודא דדייני התם ליכא למיקם עלה דמילתא הכא איכא למיקם עלה דמילתא

ומאי שנא מהא דתנן המחליף פרה בחמור וילדה וכן המוכר שפחתו וילדה זה אומר עד שלא מכרתי ילדה וזה אומר משלקחתי ילדה יחלוקו

התם להאי

are presented in court,  in which case Rab rules that the property should be divided between the claimants, and Samuel that the judges should assign it according to their own discretion?  — In that case there is no chance that further evidence should come to light,  here there is a chance that further evidence may come to light.  But why should the ruling here be different from what we have learnt: 'If a man exchanges a cow for an ass and it calves, and similarly if a man sells a female slave and she bears a child, if the seller says that the birth took place before the sale  and the purchaser that it took place after the sale,  they must share the offspring'?  In that case each