Animal Feed Regulations and Feed Additives

Animal Feed Regulations

  • State Regulation

    • Focuses on product/facility registration, labeling, and compliance monitoring.
    • Governs the distribution of all animal feeds (medicated and non-medicated) within state borders.

  • Federal Regulation

    • Primarily concerned with rules regarding the use of animal drugs and feed additives.
    • Authority is derived from the FDA if the feed or ingredients enter interstate commerce.

Federal Regulation - FDA

  • Authority and Jurisdiction
    • Holds authority over contamination issues (pesticides, chemicals, adulterants) and can take regulatory action against misleading label claims.
    • Requires registration of each manufacturing plant and submission of medicated feed applications (FD-1900).

Labeling Requirements

  • Labels must contain:
    • Brand and/or product name
    • “Medicated” statement with purpose, active ingredients, and quantities.
Example Feed Label: A&M BULL RATION MEDICATED
  • Purpose: Enhanced feed efficiency; reduces liver abscesses from Fusobacterium necrophorum and Corynebacterium.
  • Active Ingredients:
    • Tylosin: 8 grams/ton
    • Monensin: 30 grams/ton
  • Guaranteed Analysis:
    • Crude Protein: not less than 13%
    • Crude Fat: not less than 4.5%
    • Crude Fiber: not more than 13.5%
  • Ingredients: List in order of percentage in feed formulation.

Guaranteed Feed Analysis

  • Required to list minimum and maximum levels for:
    • Crude Protein
    • Crude Fat
    • Crude Fiber
    • Specific minerals (Calcium, Phosphorus, Salt, Potassium) if total mineral content exceeds 6.5%.

Energy of Commercial Feed

  • Energy values not listed on labels due to variability.
    • Primary Reason: No direct measurement of energy content; energy varies with different ingredients.
    • A common equation for Total Digestible Nutrients (TDN):
      TDN ext{( ext%)} = 87.84 - ( ext{%ADF} imes 0.7)
    • Rule of Thumb: TDN ext{( ext%)} = [80 - ext{%Crude Fiber}] + [ ext{Crude Fat} imes 2.25]

Feed Additives

  • Classes of Additives:
    • Antibiotics, Ionophores, Beta-agonists, Hormones, Direct Fed Microbials, Enzymes, Antiparasitics.

Veterinary Feed Directive (VFD)

  • A VFD is a veterinarian-prescribed authorization to use regulated feed additives in livestock.
  • Producers must obtain the VFD from their veterinarians for the purchase of medicated feed.
    • The regulation aims to reduce antibiotic resistance in medicine by controlling the use of antibiotics in livestock.

Components Affected by VFD

  • Unaffected:
    • Non-medically important products (Ionophores, Enzymes).
  • Affected:
    • Medically important products (Penicillins, Tetracyclines, etc.) used in both animals and humans.

Ionophores and Their Function

  • Examples:
    • Monensin (Rumensin), Lasalocid (Bovatec), Laidlomycin (Cattlyst).
  • Mode of Action:
    • Disrupts ion homeostasis in bacteria, leading to altered pH and energy depletion in gram-positive bacteria, favoring the growth of gram-negatives that produce propionate, which is more energetically favorable for the animal.

Average Daily Gain (ADG) with Ionophores

  • Studies show increased ADG and improved feed efficiency in cattle fed ionophores.

Beta-agonists and Their Use

  • Mechanism:
    • Stimulate fat burning, enhance muscle growth, and improve feed efficiency.
    • Approved products include Ractopamine (Paylean) and Zilpaterol (Zilmax).

Hormones in Animal Feed

  • Common usage includes Melengestrol acetate (MGA) to suppress estrus in female cattle and improve feed efficiency.

Direct Fed Microbials

  • Used for improving gastrointestinal balance and performance in stressed animals.
  • Includes probiotics, prebiotics, and yeast cultures.

Bloat Prevention Agents

  • Products such as Poloxalene (Bloat-guard) are formulated to prevent frothy bloat caused by lush pastures.