It’s March and the summer heat has started. For broiler farmers in India, summer management of poultry is all about Fans, Foggers, Sprinklers, Curtain management, Space management, feeding time, Feeder lifting, Electrolyte supplementation, Mortality control, etc. The ambient temperature for rearing birds is 24 to 26°C. Temperature above that gradually induces stress. The intensity of stress increases proportionately with an increase in temperature. Gastrointestinal tract (GIT) weight, activity including enzyme secretion, enzymatic activity, nutrient absorptive surface area, and villi dimensions are reduced significantly due to intense heat stress. According to studies done, body weight is reduced by approximately 15-20 % with an increase in 10°C to ambient temperature. Also, there is a 5 % reduction in feed intake for every 1°C rise in temperature between 32-38°C.
Apart from managing the house temperature, there is also a requirement to make changes in the nutrition and formulation of birds for summer. In this article, we will be covering different practical changes in feed formulation for broiler diets in summer.
There is a need to improve the scientific knowledge for utilizing low cost locally available agro-industrial by-products in poultry feed in order to reduce the feed cost. As feed constitutes 60 to 70 percent of the total cost of production, any attempt to reduce the feed cost may lead to a significant reduction in the total cost of production. Poultry being monogastric animals lack fiber-degrading enzymes for the breakdown of complex carbohydrates like cellulose, hemicellulose, and lignin. Since complex carbohydrate is a major component of fibrous by-products, there is a need to find ways and means for improvement in the utilization of these fibrous materials so as to incorporate these materials in poultry feed without any adverse effect on their health and production. There is an opportunity to utilize locally available materials for the economic production of broilers, backyard poultry, and Japanese quails. Hence, it was felt to evaluate these by-products for economic feeding of poultry to produce more meat and egg with less cost in Indian conditions. Considering the demand for eggs and meat in the coming years, low-cost poultry rearing is a boon for marginal farmers. There is an ever-increasing demand for conventional feed ingredients for feeding poultry. Incorporation of these feed ingredients in poultry feed has increased the cost of production enormously. Attempts to utilize locally available cheap by-products may benefit the end users by reducing the feed cost which in turn can reduce the total cost of production of meat and egg and make them easily available at a cheaper cost in rural India. The traditional sources of vitamins and proteins used in poultry rations such as fish meal, meat, bone meal, soybean meal, groundnut cake, etc. are becoming expensive in developing countries. The availability of such feed ingredients is not adequate because of the spiraling cost of raw materials and ever-increasing competition with human beings for the same food items. Hence, the search for alternative feed sources has become inevitable to reduce the feed cost (Swain et al., 2014)
Increase DAA levels in diets
Bird utilizes much more amino acids during heat stress. Supplementation of good quality protein-rich raw materials with higher digestibility is required in summer. Ideal protein formulation with digestible amino acid levels suits perfectly for summers. For summers, the digestible amino acid levels need to be increased by 3-5%. The cost of this addition can be minimized either by the use of cost-effective locally available ingredients or by including a Multi-Protease in the diets. The cost of Multi-Protease can be easily adjusted by considering 0.2% CP or 1% DAA matrix. The incorporation of good Multi-Protease enzymes is ideal to reduce amino acid variability, protein wastage, litter ammonia, and stress. It will balance all essential amino acids, optimize performance, and reduce the cost of production.
Apart from this, a deficiency of arginine and lysine increases heat load which must be taken care of in feed formulations. Additional fortification of Lysine, Methionine, and Lysine to Arginine ratio will ensure better breast meat yield in summer stress. Arginine, Tryptophan, Valine, and Glutamine are known for their direct/ indirect response to immunomodulation and feed intake.
- Increase Digestible Amino Acid levels in the diet by 3-5%
- Use either protein ingredients to increase amino acids or Multi-Protease
- Multi-Protease is a cost-effective way to optimize Amino acids without a change in diet
- The breakeven point of Multi-Protease comes at 1% DAA or 0.2% CP replacement
- Lysine, Methionine, Arginine, Tryptophan, Valine and Glutamine levels are important
Increase AME of diet
During summer feed intake will drop due to stress and limited feeding hours. To compensate for nutrient requirements, it is suggested to increase the AME of diets by 40-50 Kcal/kg. And this increment is suggested to be provided through fat/oil. Increasing fat levels in the diet generally reduces digesta passage time and optimizes the absorption of nutrients. Fat metabolism also has the lowest heat increment ensuring body cooling effects. Good quality fat and oil also enhance palatability and optimizes finished feed energy levels. If it is enhanced by the use of grains and oil seed meal, it’s better to make sure Non-Starch Polysaccharides levels are within limits. These Anti-nutritional factors increase gut viscosity and may result in feed passage. If these levels are high use of a good thermostable Xylanase, Beta-Glucanase, Mannanase, Cellulase, and Amylase can help.
- Increase AME of diet through oil by 40-50 kcal/kg
- Use good quality oil with Antioxidants and Emulsifier
- Select oil based on Lipid Evaluation Test (MIU, FFA, PV, FA Profile, and AME calculation)
- Use thermostable Multi-NSP enzymes if ME is increased through grains and oilseeds
Dietary Electrolyte Balance (DEB) Impact
DEB is calculated as (% of Na/ 23 + % of K/39.1 – % of Cl/35.5) * 10,000 Where 23, 39.1 & 35.5 denotes the atomic weight of each Na, K & Cl electrolyte respectively and 10,000 is the multiplication factor. We have observed a severe bicarbonate ion (NaHCO3) loss during summer stress & respiratory alkalosis. An increase of NaHCO3 in diets is recommended to control the loss and reduce stress. Keeping optimum DEB in summer is essential for better feed intake, daily gain, feed conversion ratio (FCR), osmotic balance, and effective evaporative cooling of the body to relieve stress. Increased DEB by 10 to 15% in summer is recommended more than in winter. The use of potassium chloride (KCl), ammonium chloride (NH4Cl), and NaHCO3 along with regularly used NaCl will help in attaining desired levels of DEB. Practically, the DEB levels are kept at more than 220 during summers. Na comes into the diet from Salt, Soda bicarbonate, MBM, and Fish meal and K comes from Soya and other salts. A well-balanced diet with high soya and MBM DEB is never a challenge. Challenge comes when lots of alternates are added which is also less digestible.
- Keep DEB levels over 220 in the summer
- Increase DEB with Salt, Soda bicarbonate, Potassium Chloride addition
- DEB is higher for high Soya based diet
- If alternate ingredients are used more add salts to balance DEB
- The addition of electrolytes through water can also help on a temporary basis
There are some additives that have a significant role to play under heat stress. These additives can assure you a high ROI and are worth including in feed. Other essential additive levels need to be increased based on feed consumption. All Vitamin and Mineral levels need to be increased by 10-20% during summer stress so that even if bird consumes less feed, these essential nutrient levels are maintained in birds. Storage of vitamins, enzymes, and probiotics in a cooler place of a feed mill avoids efficacy loss due to environmental extremities.
The inclusion of Vitamin C and Vitamin E at a level of 100-200 ppm is recommended for stress relief and immunity. Similarly, minerals like Manganese (Mn), selenium (Se), and zinc (Zn) play a key role in improving immunity. Supplementation with Vitamin D3 is useful during summer stress to fulfill any deficit of calcium absorption and for better bone mineralization. Choline chloride dosage may be increased during summer stress to ensure effective utilization of fat & nutrients and prevent fatty liver & partial methyl donor effects. The addition of betaine which acts as a methyl donor and maintains the osmotic balance of the body will be useful as an on-top application during intense summer stress. Some anti-coccidial decrease tolerance to heat and some depress water intake. These should be avoided for summers. Nicarbazine and Monensin are not suggested to use. Other additives that always aid are immunomodulators, emulsifiers, probiotics, gut health promotors, broad-spectrum toxin binders, and enzymes.
- Increase Vitamin and Mineral levels by 10-20%
- Vitamin C, Vitamin E, Vitamin D3, Choline, and Betaine inclusion are beneficial
- Anticoccidials Nicarbazine and Monensin need to be avoided
- Storage of additives needs to be done at a cooler place
- Immunomodulators, probiotics, enzymes, emulsifiers, broad-spectrum toxin binders, etc. are always helpful
- Maize is the major energy source used in Poultry Feed diets in most countries because of its easy availability, easy storage & high-energy value, and high digestibility.
- Dry maize contains the highest amount of energy ME 3350 kcal/kg & 8-13% of Crude Protein. In a very dry state, its values can be increased.
- Maize can be included in up to 70% of poultry Ration.
- While Purchase of Maize remembers maize, Maize must be dry, and fungus free and moisture content should be then 13.5 %.
- Less moisture content of Maize in Poultry Feed will accelerate good growth rate in Broiler Birds.
How to check Maize Moisture at home –
To Test Moisture content, you can use a moisture meter which is highly recommended.
You can use a traditional method. Poultry Farmers can use a simple method to check if their maize is dry enough for storage by the use of an empty transparent bottle and some normal salt. Before Purchasing maize, put a handful of Maize and ½ handful of common dry table salt in a dry bottle. Shake the bottle for 2 -3 minutes. Allow the grains to settle at the bottom of the bottle. If the salt sticks onto the walls of the transparent bottle, this is a sign that the maize is not dried well enough for storage. Otherwise, Dry the maize and repeat the test until no salt sticks to the sides of the bottle. The maize can then be stored and there is no danger of it developing mold or aflatoxins during storage.
Soya bean meal for Poultry Feed –
- Soya bean meal contains 45-49% protein and is an excellent source of lysine, tryptophan, and threonine but it is deficient in methionine.
- Raw soybeans may contain a number of toxic and inhibitory substances. These toxic, inhibitory substances and other factors in soya beans like saponins can be inactivated by proper heat treatment during processing. So it’s better to purchase from a reliable source. It can be included in up to 35% of chick’s poultry Feed.
Use of oil in poultry Feed- Oil Are Rich in energy. Oils are also an important carrier for fat-soluble vitamins A, D, E, and K. A variety of fats and oils are used in Poultry Feed Formulation Like Palm oil, Sunflower oil, Rice Bran Oil, Soya Oil, canola, rapeseed oil, sunflower oil, linseed oil, palm oil, cottonseed oil, etc. & Tallow or Animal Fat is also used In Poultry feed formulation.
In practical Poultry Feed formulation, the level of oils rarely exceeds 4% in Poultry Feed Formulations.
Lime Stone Powder for poultry Feed-Lime Stone Powder is a major source of calcium or an important part of Poultry Feed to maintain bone strength.
Dicalcium Phosphate poultry Feed- Dicalcium Phosphate is also an important source of calcium or an important part of Poultry Feed, especially for Vegetarian Poultry feed Formulation.