UNDERSTANDING HEAVY METALS "HARMFUL IONS" TOXICITY IN CHICKENS

In this edition of EggCellent Feeds, we’re diving into the often overlooked but critical topic of heavy metals toxicity in chickens. Exposure to even small amounts of certain metals through feed can severely impact poultry performance, from egg production to overall health. That’s why we've crafted a detailed infographic highlighting the toxic levels of various metals and their specific effects on poultry. Here’s a breakdown of the most significant metals and their impact:

1. Aluminum (Al)

· Toxic Level: 1000 mg/kg

· Effects: Reduced egg production, stunted growth, and the onset of rickets. Aluminum toxicity can interfere with calcium absorption, leading to brittle bones and other skeletal issues.

2. Barium (Ba)

· Toxic Level: 200 mg/kg

· Effects: Slows down growth. Prolonged exposure can affect the muscular and nervous systems, leading to weakness in birds.

3. Cadmium (Cd)

· Tolerable Level: 0.5 mg/kg

· Toxic Level: 12 mg/kg

· Effects: Decreases both egg production and growth. Cadmium also accumulates in the liver and kidneys, potentially leading to long-term health damage.

4. Fluorine (F)

· Tolerable Level: 200 mg/kg

· Toxic Level: 500 mg/kg

· Effects: Causes severe issues with growth, hatchability, and metabolic disorders. It also leads to bone deposition of fluoride, which can result in weaker skeletal structures.

5. Bromine (Br)

· Toxic Level: 5000 mg/kg

· Effects: Reduces growth. High levels of bromine can impair neurological functions and disrupt thyroid hormone balance, further affecting development.

6. Chromium (Cr)

· Toxic Level: 300 mg/kg

· Effects: Negatively affects egg quality and growth. Chromium toxicity interferes with carbohydrate metabolism and can disrupt glucose regulation.

7. Lead (Pb)

· Toxic Level: 200 mg/kg

· Effects: Leads to reduced egg production and growth. Lead accumulates in the bones and organs, causing reproductive failure and neurological damage.

8. Mercury (Hg)

· Tolerable Level: 2 mg/kg

· Toxic Level: 5 mg/kg

· Effects: Decreases growth and increases mortality rates. Mercury affects the nervous system and can lead to behavioral changes in birds, as well as developmental delays in chicks.

9. Silver (Ag)

· Toxic Level: 200 mg/kg

· Effects: Results in exudative diathesis (a condition characterized by excessive fluid leakage from blood vessels), enlarged heart, anemia, and reduced growth.

10. Strontium (Sr)

· Toxic Level: 6000 mg/kg

· Effects: Slows down growth. Strontium can replace calcium in bones, weakening skeletal structure and leading to deformities.

11. Tungsten (W)

· Toxic Level: 500 mg/kg

· Effects: Reduces growth. Tungsten exposure affects enzyme activity, leading to disruptions in energy metabolism.

12. Vanadium (V)

· Tolerable Level: 10 mg/kg

· Toxic Level: 15 mg/kg

· Effects: At low doses, vanadium can enhance growth, egg production, and albumen quality, but higher levels disrupt these benefits and cause toxicity.

13. Sulfate (SO₄²⁻)

· Toxic Level: 8000 mg/kg

· Effects: Reduces egg quality and growth. Excess sulfate can interfere with the absorption of other minerals, leading to imbalances and health issues.

14. Nitrates (NO₃⁻)

· Toxic Level: 450 mg/kg

· Effects: Decreases growth. High nitrate levels affect oxygen transport in blood, causing conditions like methemoglobinemia, which reduces oxygen supply to tissues.

15. Nitrites (NO₂⁻)

· Toxic Level: 650 mg/kg

· Effects: Reduces Vitamin A levels in the liver and causes thyroid enlargement. Nitrites convert hemoglobin to methemoglobin, impairing the oxygen-carrying capacity of blood, which can lead to suffocation in severe cases.

These heavy metals can accumulate in poultry feed through contaminated water, soil, or feed ingredients, creating significant health risks for both birds and consumers of poultry products. As poultry farmers and nutrition experts, it's crucial to monitor feed quality and keep these metals within tolerable limits to ensure healthy, productive flocks.

Adel Halbouni