Dr. Md. Emdadul Haque, Dr. Venket M Shelke & Dr. Partha Das
Kemin Industries South Asia Pvt. Ltd.
Introduction
Heat stress is a significant challenge in the poultry industry, particularly in warm, tropical, and sub-tropical regions. It reduces the performance of birds and directly impacts their economic returns. Birds are heat stressed when their net heat loss is less than their net heat production, making it challenging to balance these two factors1.
Heat stress affects birds of all types and age groups that leading to physiological consequences such as increased body core temperature, reduced voluntary feed intake, depressed immunity, altered electrolyte balance, impaired endocrine and reproductive functions, decreased energy availability, altered digestibility and metabolism of nutrients, disruption in intestinal epithelium structure and function, altered normal and protective microbiota, and increased circulatory cortisol and corticosterone levels2. To reduce heat stress production, birds resort to strategies like feed intake which results in reduced growth rate, poor meat quality, decreased egg production, and reduced feed utilization efficiency3. Nutritional management is a widely followed method to mitigate the negative impact of heat stress and reduce production losses. Meeting mineral requirements during heat stress is crucial for poultry efficiency, with trace minerals and coenzymes playing a critical role in reducing the negative effects of heat stress.
Role of trace mineral and Coenzyme Q10 in mitigation of heat stress
Zinc (Zn)
Zinc supplementation significantly enhances growth and FCR (Feed Conversion Ratio) in heat-stressed poultry4. It increases weight gain, and feed efficiency in broilers4 and improves feed conversion, and egg production in layers raised under high temperatures5.
Zinc, a key component of the carbonic anhydrase enzyme, improves eggshell weight and reduces shell defects6. It is crucial for maintaining an efficient immune system during heat stress, as it increases antibody titer Immunoglobulin G & Immunoglobulin M (IgG & IgM) and cell-mediated immunity7.
Zinc aids in quenching free radicals by participating in antioxidant enzyme systems like superoxide dismutase (SOD) and metallothionein. It also releases enzymes like catalase (CAT), glutathione peroxidase (GPx), vitamin A, and vitamin C, which raises their levels in the serum and makes it easier for the body to deal with heat stress8.
Copper (Cu)
Copper (Cu) is a crucial trace mineral in birds, essential for antioxidant activity and immunity9. Birds require 5-8 ppm of copper in their diet10. Heat stress can decrease copper intake due to reduced feed intake and increased excretion, leading to marginal copper deficiency. This impairs the immune system, reducing T lymphocyte synthesis, antibody production, and phagocytic index11. Cu supplementation during heat stress can help birds cope with the stress efficiently and maintain the eggshell and shell membrane quality in layer12.
Selenium (Se)
Selenium has a vital function in poultry's antioxidant defense system during heat stress. Organic selenium is more bioavailable than inorganic forms in chicken13. It boosts weight gain and feed efficiency in heat-stressed birds while improving feed conversion, egg output, egg quality, haugh units, and eggshell quality in layers raised at high temperatures14. It protects the mucosa of the small intestine and pancreas from oxidative damage during heat stress, enhances vitamin E absorption, and protects cell membrane fats from oxidative damage15,16. It also aids immune systems by increasing antibody titer (IgG and IgM), interleukin production (Tumour Necrosis Factor-alpha (TNF-α), Interferon gamma (INF-γ) and interleukin-2(IL 2)), and phagocytic functions of macrophages, thereby reducing the negative effects of heat stress17.
Chromium (Cr)
Chromium (Cr) is a mineral involved in the metabolism of carbohydrates, proteins, lipids, and nucleic acids through insulin action18. Chromium supplementation enhances insulin, glucose, and cholesterol levels in heat-stressed birds by restoring the Cr reservoir and utilizing glucose extensively19. It reduces oxidative stress, lipid peroxidation, and hepatic nuclear protein, and heat shock protein expression in heat-stressed layers20. Organic chromium has more bioavailability and lower toxicity than inorganic forms21. Chromium supplementation in birds reduces stress by increasing orexin and glucose transporter (GLUTs) levels and reducing nuclear factor kappa B(NF-κB) and heat shock protein (HSPs) levels, promoting a more thermoneutral physiology22.
Manganese (Mn)
Manganese (Mn) aids in carbohydrate and lipid metabolism by increasing insulin synthesis from the pancreas23. In heat-stress conditions, Mn supplementation can alleviate its negative effects on broilers, particularly in chronic heat-stressed broilers, by reducing abdominal fat deposition by decreasing lipoprotein lipase (LPL) activity24. Supplementation of Mn can protect the embryo of birds from maternal heat stress by enhancing epigenetic-activated antioxidant and anti-apoptotic activities25. It acts as a cofactor for many of the enzymes required for eggshell synthesis and helps maintain eggshell quality during heat stress conditions26.
Iodine
The thyroid gland hormones in birds significantly regulate metabolic and thermogenic functions27. Heat stress can decrease thyroid hormone concentrations in the circulatory, potentially due to a decrease in feed intake28. Heat-stressed layers have lower serum Triiodothyronine (T3), Thyroxine (T4,) and Thyroid stimulating hormone (TSH) concentrations, as well as an increase in Adrenocorticotropic hormone (ACTH) concentrations, and there is a direct correlation between plasma T3 concentration and egg productivity29. Thyroid gland function is influenced by the amount of iodine in the diet and Iodine deficiency at this stage may prove harmful to poultry30. Iodine deficiency can cause metabolic disorders and reduced laying rates31. The recommended iodine content for layers' diet should be 0.48 mg/kg of feed32.
Iron (Fe)
Iron (Fe) is an essential mineral that is regularly supplemented in poultry feed. It is a vital component in various enzymes and proteins that regulate cell development, oxygen transport, and health33. It is involved in biochemical reactions like the antioxidant system, by being part of enzymes like catalase, and various oxidation-reduction reactions, and is essential for the immune response34. It significantly supports enzymes in the tricarboxylic acid cycle (TCA), enabling the removal of harmful metabolites via catalases and peroxidases with iron35. Heat stress reduces Fe levels in serum and tissue, leading to immune and antioxidant system malfunction, causing health issues in birds36,37. Birds under heat stress should consume a normal dietary iron concentration; otherwise, the immuno-antioxidant system collapse will negatively impact animal health37.
Coenzyme Q10 (CoQ10)
Coenzyme Q10 (CoQ10), also known as ubiquinone, is a lipophilic antioxidant found in the mitochondria of all body cells38. It has various homologs based on an isoprenoid moiety, with CoQ10 being prominent in humans and birds39. It serves as an electron carrier in the mitochondrial respiratory chain and a lipid-soluble antioxidant40. It is an important bioactive compound that can strongly remove free radicals from cells41. The body synthesizes it, but excessive free radical scavenging during heat stress depletes it41. CoQ10 can be used as a nutritional supplement for various beneficial effects, including:
- CoQ10 significantly enhanced the performance (body weight gain, feed intake, and F:G ratio) of broilers, particularly grower and finisher stage in heat stress conditions41.
- CoQ10 lowered the levels of glucose, cholesterol, triglycerides, and corticosterone in the blood, which is a key biomarker for heat stress. This could be because CoQ10 reduces the oxidative effects of heat stress42.
- T3, T4, and their balance control animal body temperature and metabolic activity. Heat-stressed birds consistently have decreased T3 and T4 concentrations. CoQ10 enhanced T4 concentrations in blood serum, demonstrating its capacity to reduce the deleterious effects of heat stress41.
- Heat stress in broiler chickens increases the H/L ratio index, affecting the number of lymphocytes and heterophiles. CoQ10 supplementation can decrease the H/L ratio, potentially reducing its harmful effects42.
- Broiler chicken’s susceptibility to ascites (pulmonary hypertension syndrome)) is reduced by CoQ10 supplementation, which improves hepatic mitochondrial function, respiratory chain-related enzyme activities, and mitochondrial antioxidative activity42.
- Dietary CoQ10 significantly increased hepatic CoQ10 levels in laying hens, and it acts as an HMGR (hydroxymethyl-glutamyl-CoA reductase) inhibitor in the livers, suppressing cholesterol synthesis, which in turn results in a reduction in egg yolk cholesterol43.
- Dietary CoQ10 supplementation may increase tissue concentrations, which may restore mitochondrial functions and regulate Pdss2 (decaprenyl-diphosphate synthase subunit 2), BMP15 (bone morphogenetic protein 15), and GDF9 (growth differentiation factor 9) mRNA transcripts, improving oocyte quality and broiler breeders' incubated eggs' hatchability44.
- Coenzyme Q10 plays a crucial role in the regeneration of antioxidants like superoxide dismutase and vitamin E45. As a result, these antioxidants improve sperm quality and prevent lipid peroxidation in the sperm plasma membranes of male broiler breeders46.
Kemtrace® Supreme
Kemtrace® Supreme is a highly bioavailable complete organic mineral mix of Metal Propionates ensuring optimal mineral nutrition to broiler, layer, and breeder birds and reducing oxidative stress to enhance absorption.
- IOMPS- State of the art Manufacturing: Kemin’s Metal Propionates are manufactured in the new Integrated Organic Mineral Production System; With more stable minerals and better mineral complex formation.
- A fully Organic formulation: Zn, Mn, Cu, Co, Cr in Metal Propionates form; Iron as Iron Ascorbate; Selenium as Se Yeast; Iodine as EDDI
- Optimized Mineral concentration: All the minerals are optimized to fulfill the nutrient requirement; Higher Zn, Mn, and Cr concentrations to fit the needs of Broiler, Layer, and Breeders.
- Boosted with Antistress Factors: Coenzyme Q 10 (Antistress factor) is added to reduce oxidative stress; higher Chromium concentration to reduce stress, boost immunity, and increase meat yield.
- Conclusion
- Heat stress poses a significant threat to the poultry industry due to rising global temperatures. Despite various strategies, the industry largely uses only a few. Heat stress is caused by factors like high environmental temperature, humidity, radiant heat, and airspeed, causing physiological, neuroendocrine, and behavioral changes. No single approach can fully mitigate its effects. A holistic approach is needed to mitigate heat stress's negative effects. Trace minerals and CoQ10 can effectively alleviate some adverse effects. Supplementation of these minerals and coenzyme combinations is crucial for birds to fully recover and perform efficiently during heat stress. Combining CoQ10 and trace minerals can offer benefits to poultry in hot regions, reducing the negative impacts of high ambient temperatures.
References are available on request
