Climate Change Impact on Immune …
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5 Nutritional Applications for Heat Stress Mitigation
All poultry species are severely affected by heat stress conditions, preventing their
access to the maximum biological performance, so it was necessary to search for
modern solutions along with the traditional methods to challenge heat stress in order
to protect birds and maintain their production. Nutritional solutions have now become
more important to mitigate the detrimental effects of heat stress on birds, and this
can be achieved by applying one or more nutritional procedures.
5.1 Using a High-Energy Diet
Birds mainly consume food to satisfy their energetic needs required for maintain
life and perform various physiological functions. Fats contain 2.25 times the calories
per unit of weight than protein or carbohydrates; generally they are used to increase
the energy density of poultry diets. Indeed, fat gives less biological heat production
compared to either protein or carbohydrates, because dietary fat metabolism has
lower heat increment than protein or carbohydrates. Fat is characterized by decreasing
the physiological duty inside the body leading to higher utilization of food energy to
be used in different production functions, unlike the carbohydrate energy, which is
characterized by the high amount of energy loses during digestion and metabolism.
Recently, researches revealed the benefits of supplementing poultry diets with
vegetable oils to account for about 33% of the total dietary energy, replacing part of
the traditional energy source (carbohydrate). Where it was noted that supplementing
oils or fats by 3–5% of the diet increased the appetite and taste of feed, also it increased
the utilization of various nutrients in the feed consumed, besides fat contains good
amounts of soluble vitamins (A, D3, E, K) and the essential fatty acid (linoleic acid)
needed for growth and egg production.
However, caution should be considered when formulating such these feeds since
an appropriate antioxidant should be supplemented and not storing the feed for a
long time in order to avoid fat rancidity.
5.2 Dietary Protein and Amino Acid
The requirements of protein and amino acids should be met at the recommended
levels for growth and egg production, taking into consideration not to excessively
increase the dietary protein level especially under heat stress conditions as the heat
increment associated with protein catabolism is higher when compared to that of fats
or carbohydrates.
Supplementation of essential amino acids is profitable for reducing the internal
heat loss which leads to reduce the adverse effect of high temperature, in this regard
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5 Nutritional Applications for Heat Stress Mitigation
All poultry species are severely affected by heat stress conditions, preventing their
access to the maximum biological performance, so it was necessary to search for
modern solutions along with the traditional methods to challenge heat stress in order
to protect birds and maintain their production. Nutritional solutions have now become
more important to mitigate the detrimental effects of heat stress on birds, and this
can be achieved by applying one or more nutritional procedures.
5.1 Using a High-Energy Diet
Birds mainly consume food to satisfy their energetic needs required for maintain
life and perform various physiological functions. Fats contain 2.25 times the calories
per unit of weight than protein or carbohydrates; generally they are used to increase
the energy density of poultry diets. Indeed, fat gives less biological heat production
compared to either protein or carbohydrates, because dietary fat metabolism has
lower heat increment than protein or carbohydrates. Fat is characterized by decreasing
the physiological duty inside the body leading to higher utilization of food energy to
be used in different production functions, unlike the carbohydrate energy, which is
characterized by the high amount of energy loses during digestion and metabolism.
Recently, researches revealed the benefits of supplementing poultry diets with
vegetable oils to account for about 33% of the total dietary energy, replacing part of
the traditional energy source (carbohydrate). Where it was noted that supplementing
oils or fats by 3–5% of the diet increased the appetite and taste of feed, also it increased
the utilization of various nutrients in the feed consumed, besides fat contains good
amounts of soluble vitamins (A, D3, E, K) and the essential fatty acid (linoleic acid)
needed for growth and egg production.
However, caution should be considered when formulating such these feeds since
an appropriate antioxidant should be supplemented and not storing the feed for a
long time in order to avoid fat rancidity.
5.2 Dietary Protein and Amino Acid
The requirements of protein and amino acids should be met at the recommended
levels for growth and egg production, taking into consideration not to excessively
increase the dietary protein level especially under heat stress conditions as the heat
increment associated with protein catabolism is higher when compared to that of fats
or carbohydrates.
Supplementation of essential amino acids is profitable for reducing the internal
heat loss which leads to reduce the adverse effect of high temperature, in this regard