What follows is a short abstract of the 1988 Animal Welfare Act, the federal law which governs the humane treatment of animals.  I also provide the texts of the anti-cruelty statutes of Illinois and Missouri


as amended

(7 U.S.C. ¤¤ 2131 et. seq.)

Section 1.
(a) This Act may be cited as the "Animal Welfare Act".
(b) The Congress finds that animals and activities which are regulated under this Act are either in interstate or foreign commerce or substantially affect such commerce or the free flow thereof, and that regulation of animals and activities as provided in this Act is necessary to prevent and eliminate burdens upon such commerce and to effectively regulate such commerce, in order-- (1) to insure that animals intended for use in research facilities or for exhibition purposes or for use as pets are provided humane care and treatment; (2) to assure the humane treatment of animals during transportation in commerce; and (3) to protect the owners of animals from the theft of their animals by preventing the sale or use of animals which have been stolen.
The Congress further finds that it is essential to regulate, as provided in this Act, the transportation, purchase, sale, housing, care, handling, and treatment of animals by carriers or by persons or organizations engaged in using them for research or experimental purposes or for exhibition purposes or holding them for sale as pets or for any such purpose or use. The Congress further finds that-- (1) the use of animals is instrumental in certain research and education for advancing knowledge of cures and treatment for diseases and injuries which afflict both humans and animals; (2) methods of testing that do not use animals are being and continue to be developed which are faster, less expensive, and more accurate than traditional animal experiments for some purposes and further opportunities exist for the development of these methods of testing; (3) measures which eliminate or minimize the unnecessary duplication of experiments on animals can result in more productive use of Federal funds; and (4) measures which help meet the public concern for laboratory animal care and treatment are important in assuring that research will continue to progress.
 e) The term "research facility" means any school (except an elementary or secondary school), institution, organization, or person that uses or intends to use live animals in research, tests, or experiments, and that (1) purchases or transports live animals in commerce, or (2) receives funds under a grant, award, loan, or contract from a department, agency, or instrumentality of the United States for the purpose of carrying out research, tests, or experiments...
(f) The term "dealer" means any person who, in commerce, for compensation or profit, delivers for transportation, or transports, except as a carrier, buys, or sells, or negotiates the purchase or sale of, (1) any dog or other animal whether alive or dead for research, teaching, exhibition, or use as a pet, or (2) any dog for hunting, security, or breeding purposes, except that this term does not include (i) a retail pet store except such store which sells any animals to a research facility, an exhibitor, or a dealer; or (ii) any person who does not sell, or negotiate the purchase or sale or any wild animal, dog, or cat and who derives no more than $500 gross income from the sale of other animals during any calendar year;
(g) The term "animal" means any live or dead dog, cat, monkey (nonhuman primate mammal), guinea pig, hamster, rabbit, or such other warm-blooded animal, as the Secretary [that is, the Secretary of Agricolture] may determine is being used, or is intended for use, for research, testing, experimentation, or exhibition purposes or as a pet; but such term excludes horses not used for research purposes and other farm animals, such as, but not limited to livestock or poultry, used or intended for use as food or fiber, or livestock or poultry used or intended for improving animal nutrition, breeding, management or production efficiency, or for improving the quality of food or fiber. With respect to a dog the term means all dogs including those used for hunting, security, or breeding purposes;
(h) The term "exhibitor" means any person (public or private) exhibiting any animals, ... and such term includes carnivals, circuses, and zoos exhibiting such animals whether operated for profit or not; but such term excludes retail pet stores, organizations sponsoring and all persons participating in State and country fairs, livestock shows, rodeos, purebred dog and cat shows, and any other fairs or exhibitions intended to advance agricultural arts and sciences, as may be determined by the Secretary;
Section 13. (a)
(1) The Secretary shall promulgate standards to govern the humane handling, care, treatment, and transportation of animals by dealers, research facilities, and exhibitors.
(2) The standards described in paragraph (1) shall include minimum requirements...for handling, housing, feeding, watering, sanitation, ventilation, shelter from extremes of weather and temperatures, adequate veterinary care, and separation by species where the Secretary finds necessary for humane handling, care, or treatment of animals;....
(3) In addition to the requirements under paragraph (2), the standards described in paragraph (1) shall, with respect to animals in research facilities, include requirements-- (A) for animal care, treatment, and practices in experimental procedures to ensure that animal pain and distress are minimized, including adequate veterinary care with the appropriate use of anesthetic, analgesic or tranquilizing drugs, or euthanasia; (B) that the principal investigator considers alternatives to any procedure likely to produce pain or distress in an experimental animal; (C) in any practice which could cause pain to animals- (i) that a doctor of veterinary medicine is consulted in the planning of such procedures; (ii) for the use of tranquilizers, analgesics, and anesthetics; (iii) for presurgical and postsurgical care by laboratory workers in accordance with established veterinary medical and nursing procedures; (iv) against the use of paralytics without anesthesia; and (v) that the withholding of tranquilizers, anesthesia, analgesia, or euthanasia when scientifically necessary shall continue for only the necessary period of time;
(D) that no animal is used in more than one major operative experimenta from which it is allowed to recover except in cases of--(i) scientific necessity; or (ii) other special circumstances as determined by the Secretary;
(6)(A) Nothing in this Act--(i) except as provided in paragraph (7) of this subsection, shall be construed as authorizing the Secretary to promulgate rules, regulations, or orders with regard to design, outlines, guidelines or performance of actual research or experimentation by a research facility as determined by such research facility;
(7) (A) The Secretary shall require each research facility to show upon inspection, and to report at least annually, that the provisions of this Act are being followed and that professionally acceptable standards governing the care, treatment, and use of animals are being followed by the research facility during actual research or experimentation.
(B) In complying with subparagraph (A), such research facilities shall provide--(i) information on procedures likely to produce pain or distress in any animal and assurances demonstrating that the principal investigator considered alternatives to those procedures; (ii) assurances satisfactory to the Secretary that such facility is adhering to the standards described in this section; and (iii) an explanation for any deviation from the standards promulgated under this section.
(8) ... (b)(1) The Secretary shall require that each research facility establish at least one Committee. Each Committee shall be appointed by the chief executive officer of each such research facility....Of the members of the Committee...at least one member shall be a doctor of veterinary medicine; at least one member... shall not be affiliated in any way with such facility... [and] ...is intended to provide representation for generaly community interests in the proper care and treatment of animals...
Section 26.
(a) It shall be unlawful for any person to knowingly sponsor or exhibit an animal in any animal fighting venture to which any animal was moved in interstate or foreign commerce.
(b) It shall be unlawful for any person to knowingly sell, buy, transport, or deliver to another person or receive from another person for purposes of transportation, in interstate or foreign commerce, any dog or other animal for purposes of having the dog or other animal participate in an animal fighting venture.
(c) It shall be unlawful for any person to knowingly use the mail service of the United States Postal Service or any interstate instrumentality for purposes of promoting or in any other manner furthering an animal fighting venture except as performed outside the limits of the States of the United States.
(d) Notwithstanding the provisions of subsection (a), (b), or (c) of this section, the activities prohibited by such subsections shall be unlawful with respect to fighting ventures involving live birds only if the fight is to take place in a State where it would be in violation of the laws thereof...
(g) for purposes of this section..... the term "animal" means any live bird, or any live dog or other mammal, except man.

The USDA, following the requirements of the AWA, produced regulations.  It also clarified the meaning of "animal" in the following way:

"Animal means any live or dead dog, cat, nonhuman primate, guinea pig, hamster, rabbit, or any other warmblooded animal, which is being used, or is intended for use for research, teaching, testing, experimentation, or exhibition purposes, or as a pet. This term excludes: Birds, rats of the genus Rattus and mice of the genus Mus bred for use in research, and horses not used for research purposes and other farm animals, such as, but not limited to livestock or poultry, used or intended for use as food or fiber, or livestock or poultry used or intended for use for improving animal nutrition, breeding, management, or production efficiency, or for improving the quality of food or fiber. With respect to a dog, the term means all dogs, including those used for hunting, security, or breeding purposes."


70/3.02. Aggravated cruelty

§ 3.02. Aggravated cruelty. No person may intentionally commit an act that causes a companion animal to suffer serious injury or death. Aggravated cruelty does not include euthanasia of a companion animal through recognized methods approved by the Department of Agriculture.


578.009. Animal neglect--penalties

1. A person is guilty of animal neglect when he has custody or ownership or both of an animal and fails to provide adequate care or adequate control, including, but not limited to, knowingly abandoning an animal in any place without making provisions for its adequate care which results in substantial harm to the animal.

2. Animal neglect is a class C misdemeanor upon first conviction and for each offense, punishable by imprisonment or a fine not to exceed five hundred dollars, or both, and a class B misdemeanor punishable by imprisonment or a fine not to exceed one thousand dollars, or both upon the second and all subsequent convictions. All fines and penalties for a first conviction of animal neglect may be waived by the court provided that the person found guilty of animal neglect shows that adequate, permanent remedies for the neglect have been made. Reasonable costs incurred for the care and maintenance of neglected animals may not be waived.