Feed dealers and processors sometimes enter into contractual arrangements with farmers under which the latter agree to raise to marketable size baby chicks supplied by the former who also undertake to furnish all the required feed and possibly additional items. Typically, the feed dealer or processor retains title to the chickens until they are sold. Under such an arrangement, the activities of the farmers and their employees in raising the poultry are clearly within section 3(f). The activities of the feed dealer or processor, on the other hand, are not “raising of poultry” and employees engaged in them cannot be considered agricultural employees on that ground. Employees of the feed dealer or processor who perform work on a farm as an incident to or in conjunction with the raising of poultry on the farm are employed in “secondary” agriculture (see §§ 780.137 et seq. and Johnston v. Cotton Producers Assn., 244 F. 2d 553).