Mass. Gen. Laws ch. 129 § 19
Inspectors shall make regular and thorough inspections of all neat cattle, sheep and swine found within the limits of their respective towns. Such inspection shall be made at such times and in such manner as the director shall from time to time order. They shall also from time to time make inspections of all other domestic animals within the limits of their respective towns if they know, or have reason to suspect, that such animals are affected with or have been exposed to any contagious disease, and they shall immediately inspect all domestic animals and any place where any such animals are kept whenever directed so to do by the director; but this section shall not apply to the inspection of sheep or swine slaughtered in wholesale slaughtering establishments, or to the obtaining of a license for the slaughtering of such sheep or swine.
Mass. Gen. Laws ch. 129, § 19