וּפָרָ֤ה וָדֹב֙ תִּרְעֶ֔ינָה יַחְדָּ֖ו יִרְבְּצ֣וּ יַלְדֵיהֶ֑ן וְאַרְיֵ֖ה כַּבָּקָ֥ר יֹֽאכַל־תֶּֽבֶן׃
And the cow and the bear feed; Their young ones shall lie down together; And the lion shall eat straw like the ox.
Ibn Ezra on Isaiah
פרה The large cattle; the younger of the breed is called עגל (ver. 6). Some assert that the female of cattle is stronger than the male.8This remark of I. E. is perhaps to explain, why the feminine form פרה is used with the masculine רב for the whole species.
Ibn Ezra on Isaiah
Shall eat straw. As if his nature had changed, and he would no more, in seeking prey, inflict suffering upon others.