Abu Hurairah said A man from Banu Fazarah came to the Prophet (ﷺ) and said “My wife has given birth to a black son”. He said “Have you any camels?” He said “They are red”. He asked “Is there a dusky one among them?” He replied “Some of them are dusky”. He asked “How do you think they have come about?” He replied “This may be a strain to which they reverted”. He said “And this is perhaps a strain to which the child has reverted.”
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا ابْنُ أَبِي خَلَفٍ، حَدَّثَنَا سُفْيَانُ، عَنِ الزُّهْرِيِّ، عَنْ سَعِيدٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ جَاءَ رَجُلٌ إِلَى النَّبِيِّ صلى الله عليه وسلم مِنْ بَنِي فَزَارَةَ فَقَالَ إِنَّ امْرَأَتِي جَاءَتْ بِوَلَدٍ أَسْوَدَ فَقَالَ " هَلْ لَكَ مِنْ إِبِلٍ " . قَالَ نَعَمْ . قَالَ " مَا أَلْوَانُهَا " . قَالَ حُمْرٌ قَالَ " فَهَلْ فِيهَا مِنْ أَوْرَقَ " . قَالَ إِنَّ فِيهَا لَوُرْقًا . قَالَ " فَأَنَّى تُرَاهُ " . قَالَ عَسَى أَنْ يَكُونَ نَزَعَهُ عِرْقٌ . قَالَ " وَهَذَا عَسَى أَنْ يَكُونَ نَزَعَهُ عِرْقٌ " .
sunnah.com