Channegowda and Akanksha Patel
Technical services, Zeus Biotech, Mysore
India produces about 14 MMT of broiler feed, 13 MMT of layer feed and 3 MMT of breeder feed per annum. In addition to energy, protein, amino acid and vitamins, minerals are also crucial for optimum growth, reproduction and immunity.
The general functions of the minerals:
- Give rigidity and strength to skeleton (calcium, phosphorus, magnesium)
- Serve as constituents of organic compounds (sulphur in proteins, cobalt in vitamin B12, iron in red blood cells)
- Activate enzyme systems (phosphorus, manganese and zinc)
- Osmoregulation and acid base balance (sodium, potassium, chloride)
- Required to synthesize hormones thyroxine (Iodine)
- Muscle contractions and transmission of nerve impulses (sodium and calcium)
CLASSIFICATION OF MINERALS
In general, minerals are classified into macro and microminerals. Macro minerals such as calcium, phosphorus, magnesium, sodium, potassium, chloride and sulphur are required in comparatively higher amounts (g/kg). Whereas microminerals (trace minerals) are required in lesser amounts (mg/kg or ppm). Though trace minerals (TMs) are required in small quantities, their undersupply can result in deficiencies, while oversupply may lead to toxicity. Therefore, it is very important to deliver the optimum level of all trace minerals to prevent deficiencies and to get optimum performance. The Inclusion level of trace minerals in poultry feed ranges from 0.1 to 0.13% of the diet, contributing to an approximate annual usage of 0.027 to 0.038 MMT.
Figure 1. General classification of trace minerals:
Traditionally, trace minerals are incorporated in the form of inorganic salts such as oxides, chlorides and sulphates. Inorganic trace minerals are highly soluble and get ionized during digestion, forming ‘free’ reactive ions. These free ions can interact with other minerals or other components of the diet to form insoluble and unabsorbable complexes. The inorganic trace minerals can also bind with natural chelating agents present in feeds, such as phytic acid and oxalic acid, which can also limit their absorption. These interactions make the minerals partially or completely unavailable to the animal, resulting in reduced bioavailability.
To address this, poultry producers have increased the inclusion levels of inorganic trace minerals in poultry diets from 0.75 to 1.5 kg/tonne of feed which is often higher than the requirement. The higher inclusion levels lead to an over-supply of minerals not only resulting in unnecessary wastage but also contributing to environmental pollution (manure/soil). Additionally, inorganic trace minerals tend to get contaminated with heavy metals (lead, mercury, arsenic, cadmium) and dioxins which are not only toxic to poultry but also raise concerns for food safety.
Poultry producers and Nutritionists are increasingly aware of the disadvantages of poorly metabolized inorganic trace minerals, leading to replacement of inorganic trace minerals with organic trace minerals. Currently, organic trace minerals are widely used in animal nutrition and the percentage of organic v/s inorganic trace minerals fed in the ration has been changing over a period of time. The guidelines provided by the NRC/ARC/BIS/INRA are for the use of inorganic trace minerals only and not for the organic minerals. In practice, most nutritionists feed organic trace minerals up to 30 to 50% of inorganic trace minerals. The positive responses have also been observed when inorganic trace minerals are completely (100 percent) replaced with organic trace minerals.
VARIOUS FORMS OF ORGANIC TRACE MINERALS:
Organic and inorganic trace minerals differ fundamentally. Inorganic trace minerals are typically presented as finely ground mineral salts. These can be transformed into organic trace minerals by complexing them with an organic molecule known as ligand. The ligand could be single amino acid (chelates) or a chain of amino acids (proteinates). This binding process can be achieved either by a chemical reaction, where trace minerals are bound to synthetic amino acids like glycine / methionine or by a biotechnological process (fermentation) where trace minerals are complexed with peptides derived from hydrolysis of soy proteins. This process of complexation protects organic trace minerals from interactions and antagonism which makes them more stable and bioavailable. The approximate bioavailability of organic trace minerals is twice or greater than that of inorganic minerals (Spears, 2003).
Supplementation of fermented organic trace mineral resulted in improved retention and less excretion
| Groups | % Excretion | % Retention |
| 100% Inorganic copper | 58.39a ± 2.59 | 41.62c ± 2.45 |
| 50% Organic copper | 39.18bc ± 3.45 | 60.81ab ± 1.35 |
| P ≤ 0.05 Aminullah et al., 2021: Indian Journal of Animal Research | ||
Table 1. Result of supplementation of fermented organic minerals
APPLICATION AND BENEFITS OF OTMS IN POULTRY NUTRITION:
Organic trace minerals are incorporated into poultry diets by various means which are given here below.
Complete replacement: Completereplacement of inorganic with organic allows a significant reduction in the inclusion rate. The standard inclusion rate for inorganic is 1 kilo per ton of feed, while the organic requires a lower inclusion rate of 500 g per ton of feed. Whereas the fermented organic offers an even lower inclusion rate of 350 g per ton of feed. This reduction in inclusion level not only saves space in the feed formula but also helps to reduce environmental pollution.
Combined Application: In practice, most of the poultry nutritionists / producers prefer a 50:50 ratio of inorganic and organic trace minerals. Several genetic companies also recommend this method of application.
On-Top Application: The on-top application of organic trace minerals is also not uncommon. In this method, organic trace minerals are added between 20-30% of inorganic trace minerals without altering the standard inclusion level of inorganic. This approach allows the nutritionist to understand the beneficial effect of organic trace minerals at farm level.
Supplementation Of Organic Trace Minerals in Poultry Diets
| Treatment | Gain (g/bird) | FCR | |
| Inorganic 750 g/t | 2824a | 1.466b | |
| Fermented organic 375 g/t | 3007b | 1.404a | |
| P≤0.05 Bob Swick et al., 2018: Poultry Science | |||
Table 2. Supplementation Of Organic Trace Minerals in Poultry Diets
Breast Meat Yield of Vencobb 400 Broilers:
| Treatment | Breast meat % of carcass |
| Inorganic: 1 kg/ton | 22.05a |
| Fermented organic: 0.50 kg/ton | 24.21b |
| P ≤ 0.001 S Haldar, 2012: unpublished | |
Table 3. Breast Meat Yield of Vencobb 400 Broilers
Bone Ash In Cobb 400 Broilers:
| Groups | Zn | Mn | Cu |
| Inorganic (1.2kg/t) | 236b | 168 b | 29b |
| Fermented organic (0.5 kg/t) | 257a | 196 a | 35a |
| P ≤ 0.05 S V Ramarao,2009: unpublished | |||
Table 4. Bone Ash in Cobb 400 Broilers
The supplementation of organic trace minerals enhances poultry production, especially in parents, organic minerals boost fertility, which in turn improves the hatchability that could result in 1or 2 additional chicks per mother per cycle.
In egg laying hens, organic trace minerals improve shell strength, decrease the number of broken and thin shelled eggs, improves the thickness of egg white (Haugh Unit Score) and helps the producers / farmers to store the egg for longer duration at room temperature specially in summer.
In broilers, improved skeletal development and bone ash improves lameness score. Additionally, improved breast growth and meat quality contribute to higher economic returns.
Conclusion:
The change-over from inorganic to organic addresses several critical issues.
- Improve growth, performance and meat quality
- Better immune response
- Lower inclusion rate saves space in feed formulations
- Higher retention addresses environmental pollution
References:
- Aminullah, N., Prabhu, T.M., Naik, J., Suresh, B.N., Chikkaramappa, T. and Umashankar, B.C. 2022. Effect of organic and nano forms of copper at reduced dietary levels on excretion and tissue deposition of selected minerals in Giriraja chicken. Animal Nutrition and Feed Technology, 22: 489-501.
- Sadeq, S. A., Wu, S. B., Choct, M. and Swick, R. A. 2018. Influence of trace mineral sources on broiler performance, lymphoid organ weights, apparent digestibility and bone mineralization. Poultry Science, 97(9): 3176-3182.
- Spears, J. W. 2008. Trace mineral nutrition—What is important and where do organic trace minerals fit in. In Proceeding of Southwest Nutrition Management Conference, University of Arizona, Tucson, 20:2016.
******
Table 1. Result of supplementation of fermented organic minerals. 2
Table 2. Supplementation Of Organic Trace Minerals In Poultry Diets. 3