2/25/2018 Using Alternative Feed Ingredients in Livestock Diets Dr. Brian Richert Purdue University March 8, 2017 “Consumers want animal protein raised with same natural supplements humans use” 62% of Millennials (80% have changed their diets) 72% new of natural health supplements were available for livestock 43% recognized probiotics Cargill Feed4Thought survey of 1000 consumers - Feb 13, 2018, published in FeedStuffs 1 2/25/2018 Antimicrobial Regulatory Environment 6 key areas of change in the next 5 years: 1. Withdrawal of growth promotion uses of antibiotics 2. Expansion of antimicrobial use reporting 3. Legislative initiatives to remove antimicrobial class for prevention or control of disease in food animals 4. Increased sensitivity of FSIS residue testing (LS-HPLC) Penicillin example 5. Use of the AMDUCA regulations as a regulatory tool to attempt to decrease use of targeted drug classes in food animals 6. Potential for FDA/CVM hearings on the hazard status of the use of tetracyclines and penicillins (likely other drugs) in animal feed. Antibiotic Usage Reporting – FDA 2016 (Dec. 2017) • Annually, each drug manufacturer must report the sales and distribution Route lbs of antibiotics that are approved for use Med. Import. Feed 13,173,052 in food animals. Injection 766,126 • Is reported by pounds of active ingredient Intramammary 35,578 • Limitations: Oral or 199,021 • Not actual usage data Topical • Some drugs approved for food animals AND companion animals Water 4,222,053 • Veterinarians are authorized to Total 18,395,828 change dose in non-feed related Not Med. All Routes 12,366,807 antimicrobials Import. • Not species specific. 2 2/25/2018 Medically Important Feed Grade Antibiotics Antimicrobial Specific drugs approved for use in feed Class Aminoglycosides Apramycin, Hygromycin B, Neomycin, Streptomycin Diaminopyrimidines Ormetoprim Lincosamides Lincomycin Macrolides Erythromycin, Oleandomycin, Tylosin Penicillins Penicillin Streptogramins Virginiamycin Sulfas Sulfadimethoxine, Sulfamerazine, Sulfamethazine, Sulfaquinoxaline Tetracycline Chlortetracycline, Oxytetracycline 3 2/25/2018 Medically Important Water Soluble Antibiotics Antimicrobial Class Specific drugs approved for use in water Aminoglycosides Apramycin, Gentamicin, Neomycin, Spectinomycin, Streptomycin Lincosamides Lincomycin Macrolides Carbomycin, Erythromycin, Tylosin Penicillins Penicillin Sulfas Sulfachloropyrazine, Sulfachlorpyridazine, Sulfadimethoxine, Sulfamerazine, Sulfamethazine, Sulfaquinoxaline Tetracycline Chlortetracycline, Oxytetracycline, Tetracycline Antibiotics NOT affected by Guidance 209/213 Antibiotics that are not medically important: Ionophores (monensin, lasalocid, narasin (Skycis,etc. ) Bacitracin (BMD, bacitracin zinc) Bambermycins (Flavomycin) Tiamulin (Denagard) Carbadox (Mecadox) Other drugs (that are not antibiotics), including: Anthelmentics: Coumaphos, Fenbendazole, Ivermectin Beta agonists: Ractopamine, Zilpaterol Coccidiostats: Clopidol, Decoquinate, Diclazuril 4 2/25/2018 Key Gut Functions Food digestion – enzyme development. Nutrient absorption – transport systems, etc. Barrier function – e.g. chemical & physical barrier: pH in stomach, mucus layer, etc. Microbiota - diversity, balance between ‘beneficial’ bacteria & pathogens. Immune system – active system that if not over-stimulated, secrete immunomolecules “The Search for the Magic Bullet” Antibiotics They work Results can be variable Antibiotic alternatives In general, positive results are less than and/or less consistent than antibiotics. However, positive results have been observed How do we increase/optimize their efficacy? How do we chose the alternative product? When do we use them? Why? – Enteric vs Respiratory vs Systemic 5 2/25/2018 Main Antibiotic Alternatives of Interest Key ingredients (Plasma, TM, Syn. AA) Direct Fed Antimicrobials (DFM) / Probiotics Prebiotics Organic Acids Fiber types Essential Oils Enzymes Seaweed Extracts Others: Yeast fractions, herbal compounds Direct Fed Antimicrobial 6 2/25/2018 Direct Fed Microbials Definition: “a source of live (viable), naturally occurring microorganisms.” (FDA) Live microorganisms which when administered in adequate amounts exert a health benefit on the host’ (FAO/WHO) Postulated Modes of Action of DFMs Competitive inhibition of gut epithelial receptors Competition for nutrients Production and secretion of antimicrobial compounds Stimulation of the immune system Gut – Brain axis – modifying behaviors 7 2/25/2018 Competitive inhibition of gut epithelial receptors Pathogen DFM Competitive inhibition of gut epithelial receptors Often referred to as “competitive exclusion” If a DFM is classified as a competitive exclusion product, then it is classified as a drug by FDA- CVM, and therefore must be approved through a new drug application. 8 2/25/2018 Competition for Nutrients Micoorganisms in a continuous flow culture will compete for nutrients Therefore, it is possible that this occurs in the GIT Production and Secretion of Antimicrobial Compounds Bacteriocins Hydrogen peroxide Organic acids Bacteriocin: A substance that certain bacteria can release which kills closely-related strains of other bacteria, but without rupturing their cell membranes. 9 2/25/2018 Microorganisms approved for use in the United States (AAFCO, 2006) 44 different organisms Aspergillus Bacillus Bacteroides Bifidobacterium Enterococcus Lactobacillus Leuconostoc Pediococcus Propionibacterium Propionibacterium shermanii Saccharomyces cerevisiae 10 2/25/2018 Simon et al., 2003 Probiotics for pathogen control • Competitive exclusion culture reduces E. coli shedding in challenged neonatal pigs (Genovese et al., 2000). • Competitive exclusion cultures reduce Salmonella Cholerasuis in challenged neonatal pigs (Fedorka-Cray et al., 1999; Genovese et al., 2003). • Microcin-producing E. coli does not reduce Salmonella shedding in weaned pigs (Frana et al., 2004). • Few (if any) defined probiotic strains with in vivo efficacy 11 2/25/2018 Prebiotics What are Prebiotics ? “A non-digestible food ingredient that beneficially affects the host by, selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon (GI Tract) that can improve the health of the host” (Gibson and Roberfroid, 1995). 12 2/25/2018 Prebiotics Most common prebiotics used are oligosaccharides which include mannan- oligosaccharide and fructo-oligosaccharides etc. Lactose, lactulose etc., are also considered prebiotic. How do oligosaccharides function? Cell surface receptor 1.Prevents pathogen binding 2. Fermentable CHO 3. Immunomodulation 13 2/25/2018 Oligosaccharides for pathogen control Few studies in pigs FOS in water reduces Salmonella shedding in challenged early-weaned pigs (Letellier et al., 1999) No effect of MOS on E. coli K88 in challenged piglets - but lower coliform (White et al., 2002) No effect of MOS on Salmonella shedding in weaners (Burkey et al., 2004) Organic Acids 14 2/25/2018 Background Post-weaning lag Insufficient HCL secretion Insufficient enzymatic secretion Immune compromised Potential for opportunistic pathogenic bacterial to colonize the GIT Diet Acidification Addition of Organic Acids Improved growth rate Improved feed efficiency Decreased scouring Decreased gastric pH Increased nutrient digestibility Altered microflora colonization of GIT HOW? 15 2/25/2018 Mode of Action Gastric/GIT pH Digesta transit time Manipulation of gut microflora Pancreatic enzyme secretion Intra-duodenal SCFA increase pancreatic secretions (Harada et al., 1986; Sano et al., 1995) Gut morphology ↑ epithelial cell proliferation with ↑ [SCFA] (Sakata et al., 1988) ↑ microvilli length and cell number with ↑ concentrations of sodium butyrate (Galfi and Bokori, 1990) Intermediary metabolism Substrates for TCA cycle ↑ aspartate transferase and succinate dehydrogenase activity with fumaric acid addition to rat diets (Tschierschwitz et al., 1982) Citric Acid Effect on Stomach pH 3.9 3.8 3.7 3.81 3.8 3.6 0.0 3.5 3.6 1.5 3.60 0.0 3.4 3.48 3.0 3.4 2.0 3.3 Stomach pH Stomach 3.31 3.33 3.2 3.2 3.1 3.0 3.0 P < 0.05 P < 0.05 Radcliffe et al., 1998 16 2/25/2018 Manipulation of Gut Microflora Selection of “beneficial” commensal bacteria by a lowering of GIT pH Acidic conditions favor the growth of lactobacillus in the stomach (Fuller, 1977) Competitive exclusion Lactobacilli → increased lactic acid → reduced pH Manipulation of Gut Microflora Bacteria H+ + A- HA H+ + A- HA Organic acids can diffuse through semi-permeable bacterial membranes and then disassociate into H+ and conjugated bases, lowering cytosolic pH and inhibiting cytosolic enzyme activity. 17 2/25/2018 Commonly Used Category Effective Against Use Acids Formic (C1) Organic Yeasts and some bacteria E.coli and salmonella in contaminated feed Potassium Organic Bacteria diformate (C1) Acetic (C2) Organic Bacteria, yeasts and Prevents E.coli molds Propionic (C3) Organic Molds Prevents E.coli Lactic (C3) Organic Bacteria Butyric (C4) Organic Bacteria Citric (C6) Organic Bacteria Sorbic (C7) Organic Yeasts, molds and some bacteria Fumaric Organic Bacteria Prevents E.coli Phosphoric Inorganic Bacteria Prevents E.coli Sulfuric Inorganic Hydrochloric Inorganic Multifactorial Analysis of the Performance Responses to Short Chain Acids (Formic, Fumaric, Citric) and Potassium Diformate in Weaned Piglets. Item Formic Acid Fumaric Acid Citric Acid Potassium diformate Experiments 6 18 9 3 Observations 10 27 19 13 Acid levels