Mo. Rev. Stat. § 537.310
In any action commenced under section 537.300, a summons may issue against the defendants upon the plaintiff stating, on oath, that he believes some one or more of his cattle or other stock has been driven off by a drover, and that he believes the same to be of a certain value, to be endorsed on the writ; and the proceedings thereon shall be the same as in other actions commenced by summons; provided, however, that no exception shall be taken to the form of the oath aforesaid, and that upon such affidavit, and the execution of a bond by plaintiff, as now required under proceedings by attachment for the amount stated in said affidavit, he shall also be entitled to an attachment against the horses, cattle, mules, hogs, sheep or other animals which defendant or defendants are then so driving, and also against their goods and chattels, and may proceed, under said attachment, to recover all damages given to plaintiff under section 537.300.
§ 537.310, RSMo