DES MOINES — A bill that sponsors say is necessary to protect Iowa’s livestock production industry is just another version of an “ag gag” law struck down by a federal judge, according to opponents of House File 775, which was approved by the Iowa House 72-24 on Tuesday and sent to the Senate.HF 775 would make “unauthorized sampling” — knowingly entering private property without consent to obtain samples of substances from agricultural animals or any soil, air, or water from farms — an aggravated misdemeanor on first offense and a Class D felony for subsequent offenses.