See BULL v.1
1398. [see BULL v.1]
1607. Topsell, Four-f. Beasts, 57. The signes of their Bulling (as it is termed) are their cries, and disorderly forsaking their fellows.
1624. Fletcher, Rule a Wife, &c. V.
1725. Bradley, Fam. Dict., I. s.v. Cow, The Advantages of their bulling at that Time is, that they will calve in ten Months.