Genesis 7:3
2 You must take with you seven pairs of every kind of clean animal, the male and its mate, two of every kind of unclean animal, the male and its mate, 3 and also seven pairs of every kind of bird in the sky, male and female, to preserve their offspring on the face of the entire earth. 4 For in seven days I will cause it to rain on the earth for 40 days and 40 nights, and I will wipe from the face of the ground every living thing that I have made.”
LXX Genesis 7:3
2 And bring in to you seven by seven some of the clean domestic animals, male and female, but two by two some of the domestic animals that are not clean, male and female, 3 and seven by seven some of the clean birds of the sky, male and female, and two by two some of the birds that are not clean, male and female, to sustain offspring upon all the earth. 4 For within seven more days I am going to bring rain on the earth for forty days and forty nights, and every thing that rises up, which I have made, I will wipe out from the face of the earth.”
Notes and References
"... Genesis 7:2–3 reports God’s command concerning how many animals Noah should take into the ark. In the Masoretic text, the distinction between unclean and clean animals concerns only land animals but not birds. Yet according to Leviticus 11:13–19 and Deuteronomy 20:25 some bird species are also unclean. Therefore, LXX Genesis 7:3 adds an appropriate distinction ..."
Meiser, Martin The Septuagint and Its Reception: Collected Essays (p. 35) Mohr Siebeck, 2022