1. Feed Additives ANS 336 Lecture 7 2/02/2001

2. Feed Additives - Defined As ingredients or combinations of ingredients added to the basic feed mix or parts thereof to fulfill a specific need. Usually used in micro quantities and requires careful handling and mixing.

3. Feed Additives- Cont’d Many classified as a drug. A substance, –Intended for use in the diagnosis, cure mitigation and treatment or prevention of diseases in animals. –Other than food intended to affect the structure or any function of the body of an animal.

4. Food and Drug Administration (FDA) Center for Veterinary Medicine Regulates use of Feed additives Clearance for testing of new feed additives requires obtaining an investigational new animal drug (INAD) to test a product. New animal drug Application( NADA) is required to market a product. Clearance IS required to use feed additives.

5. FDA Form 1900 required for human risk drugs. Category I – safest to use, no withdrawal period required. Category II – no residues allowed, withdrawal period required.

6. Delaney Clause - 1958 Congress passed the Delaney Clause in 1958 – Zero Tolerance. No substance can be used as a feed additive, even in minute amounts, if it has been in any way implicated as an inducer of cancer in either human or beast.

7. Examples of Feed Additives Antibiotics –Compound produced by microorganisms that inhibits the growth of microorganisms. –Examples of claims that can be listed on label. Improves performance (rate of gain). Improves feed efficiency or feed conversion. Increases growth rate. Increases milk production.

8. Examples of Feed Additives – cont’d Arsenicals –Controls parasites Nitrogurans –Antimicrobial compound that is produced more by a microorganism. Sulfas –Antimicrobials –Residue problems, usage has been decreased.

9. Additives Hormone like products Melengestrol acetate (MGA) –When fed to heifers to suppresses estrus –When fed to regulated estrus cycle. Implants –Ralgro –Synovex Somatotropin (rBST) –Increases milk production –Improves fertility ?

10. Growth Promotion and Feed Efficiency In general, Antibiotics are fed to reduce the incidence of Subclinical levels of bacterial infections of the digestive and respiratory tracts - thus credited with improved rate of gain and feed efficiency. Partial list……. –Chlortetracycline, Oxytetracycline, Erythromycin –Lasalocid, Monensin, Penicillin

11. Growth Promoting Chemotherapeutic –An inorganic or organic compound that inhibits the growth of organisms but is not produced by a living organism. Arsanilic acid – chicken and swine Carbadox - swine Ipronidazole - turkey Roxarsone – turkey and chicken

12. Medicinal Uses Coccidiostats –Prevent and treat Coccidiosis – Chickens and Calves. –Monensin - cattle, chickens and turkey –Lasalocid – chickens, sheep turkeys –Amprolium cattle - chickens and turkeys Histostats –For protozoan disease affecting turkey – High mortality less than 12 weeks of age. –Nitarsone

13. Medicinal Uses – cont’d Enteritis, Diarrhea, Dysentery –Carbadox – swine –Chlortetracycline – cattle, swine and chickens –Roxarsone – swine –Oxytetracycline – cattle, sheep, swine, chickens –Penicillin – chickens and turkeys –Arsanilic Acid - swine

14. Medicinal Uses – cont’d Antelmintic (worming) Agents –Fenbendazole (Safe-Guard) – swine and cattle –Invermectrin (Ivomec) – swine cattle –Levamisole hydrochloride(Tramisol) - cattle and swine –Tumatel – cattle –Thiabendazole (TBZ) – cattle, sheep, swine

15. Misc. functions of Feed Additives Enterotoxemia (overeating) disease in Sheep –Tetracyclines. Fly control –Methoprene – cattle –Rabon – cattle, horse, sheep and swine Bloat –Poloxalene

16. Medicinal Uses cont’d Ketosis –Propylene glycol dairy cattle Foot rot –Chlortetracycline Stress –Tetracyclines – cattle, chicken, turkey –Erythromycin - chickens

17. Other Feed Additives Buffers –Chemical compounds that lessen the decrease in pH caused by volatile fatty acid without causing any major increase in ruminal pH. pH = negative log 10 of the hydrogen [ ], expressed in moles per liter. –Scale where 7 is neutral and anything below is acid and anything above is alkaline.

18. Other Feed Additives cont’d Buffers cont’d –Sodium bicarbonate –Potassium bicarbonate –Calcium carbonate –Magnesium carbonate –Magnesium oxide –Sodium Bentonite –Lime – Feeding lime

19. Other Feed Additives Antioxidants – compounds that prevent rancidity of unsaturated fats. –Ethoxyquin –Vitamin E –Butylated hydroxytoluene (BHT) –Butylated hydroxyanisole (BHA) Chemical Preservatives –Ascorbic acid –Sodium nitrate –Sorbic acid –Citric Acid –Sodium nitrate

20. Other Feed Additives Pellet binding Agents –Bentonite (calcium or sodium) –Ball clay –Lignin sulfonate –Hemicellulose extract –Molasses

21. Other Feed Additives Probiotics –Consist of specific microbial cultures or ingredients or both that stimulate cultures capable of modifying the gastrointestinal environment to favor healthy tissue development. –Lactobacillus –Streptococcus –Fungi (yeast and molds) –Aspergillus –Bacillus

22. Other Feed Additives Probiotics (reasons for use) –Increase or balance the beneficial intestinal bacteria –Reduce toxic by products of digestion –Reduce intestinal pH –Improve appetite –Alleviate symptoms of STRESS –Used in Foals, dairy calves/lactating dairy cows,growing/adult horse, incoming feedlot cattle, sick pens newborn beef calves newborn pigs and various pets.

23. Other Feed Additives – Hormone like Products Melengestrol Acetate (MGA) –Synthesised steroid that is closely related structurally to progesterone (P 4 ) –Not effective in pregnant or spayed heifers or in steers. –Growth stimulation (6-8%) claimed –Improved feed efficiency (5-7%) claimed –Suppression of estrus and elevated estrogen – stimulates release of growth hormone.

24. Other Feed Additives - Implants Implant is a substance implanted into the animal body and designed for slow but constant release for growth promotion, improved feed efficiency or control of a physiological function. –Ralgro – improve gain beef and sheep (8 –12 %) claimed. Effective 70 – 110 days. –Increases secretion of growth hormone promotes skeletal growth without deposition of fat. –Synovex (Implus-S,H,C) Estrodiol benzoate, progesterone, testosterone, Not for veal calves or animals raised for breeding purposes

25. Other Feed Additives Compudose – drug impregnated silicone rubber implant –Improves rate of gain 15-20 % claimed. Finaplix (S and H) - implanted pellet Synthetic androgens 5-10 % improved gain Revelor - implant pellet

26. Other Feed Additives Bovine Somatotropin (BST) –POSILAC commercial recombinant rBST (FDA approved Feb 1994). 500 mg or 36mg/cow/day –Cannot be administered orally –Subcutaneous injection of rBST every 14 days starting day 63 postpartum. –Average increases of 8 to 10 lbs per day –Delayed dry matter intake –Require the same nutritional needs as nonsupplemented cows.

27. Summary Feed additives must be used according to label. Stiff fines for non compliance. For best results use as directed. Protect your market and livelihood.