Apparently USDA had problems with some of the comments received, because OFR shows 9 received, but only displays the text for 3. The process is described here:
This count refers to the total comment/submissions received on this docket, as of 11:59 PM yesterday. Note: Agencies review all submissions, however some agencies may choose to redact, or withhold, certain submissions (or portions thereof) such as those containing private or proprietary information, inappropriate language, or duplicate/near duplicate examples of a mass-mail campaign. This can result in discrepancies between this count and those displayed when conducting searches on the Public Submission document type. For specific information about an agency’s public submission policy, refer to its website or the Federal Register document.