The present invention provides lignin-pesticide complexes, methods for making lignin-pesticide complexes, and methods for treating or controlling insect infestations on animals by administering such complexes. Advantageously, the lignin-pesticide complexes of the present invention can be used in feed-through products to control insect infestation on livestock or pets. Various insects such as face flies, house flies, stable flies, and horn flies can be controlled and treated using the feed-through products of the present invention.