Talmud su Esodo 13:12

If one buys newly born cattle from his neighbour, [he may retain the dam] to suckle them, in the case of small cattle⁶⁷Sheep, goats, etc. for thirty days and in the case of large cattle⁶⁸Of the bovine species. for fifty days. R. Jose said: In the case of small cattle for three months because they need much attention.⁶⁹Cf. B.M. 69a (Sonc. ed., p. 402). As for attending to the first-born of cattle⁷⁰Ex. 13, 12, cf. Bekoroth 26b (Sonc. ed., p. 170). [before handing them over to the kohen], in the case of small cattle the period is thirty days and for large cattle fifty days. R. Jose said: In the case of small cattle the period is three months because they need much attention.