Monster Monday: But How Was the Cheese

Well-treated, stalled, and carefully well-bred,
Contented, calm, serene and picturesque,
Pall's herd were of the best stock,  never fed
On grain,  just grass and clover. From his desk
(Great-grandpa's), Pall ran dairy like a boss.
Then came that dewy morning when the sky
Erupted. Pall recorded not one loss
To meteor impact, at first, but by
Week's end, he noticed something wasn't right.
His girls had grown in all dimensions, and
Their milk glowed golden, like their hides by night,
While each, beneath her cowbell, grew a gland
That let them exhale flames to suit their whim.
His Kaiju Kows were soon the death of him!