पशु स्वास्थ्य और पोषण में एंटीऑक्सीडेंट की भूमिका
An antioxidant is a substance that, when present in food at a concentration lower than that of the oxidizable matrix, is significantly capable of interrupting or preventing its oxidation, Halliwell and Gutteridge (1999). Animal health and nutrition benefits from antioxidants. They are used as additives to increase the shelf life of animal feeds, premixes and fats.
Metabolic process in living organisms
Living organisms are dependent on macro- and micro- nutrients and non-nutrient (water, cutin, lignin, pigments, and waxes) components from diet that will encourage their development, growth, and proliferation.
Carbohydrates, lipids, and proteins made of carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, and other trace elements are considered to as macronutrients. These, together with micronutrients (minerals, vitamins, and bioactive substances), are essential cell components that support a wide range of processes in the cellular systems of living organisms.
For an organism to participate in normal metabolic processes (anabolism and catabolism), all of these elements must be present. This is especially the case for the production of energy through a series of oxidation reactions that take place in tissue compartments and the use of oxygen molecules (O2) by cellular systems.
Oxidation processes, also help in cellular defense actions that are necessary for the maintenance of natural life by producing components that are derived from oxygen, collectively termed as ‘free radicals’. Reactive oxygen species (ROS) and reactive nitrogen species (RNS), are generated from oxygen and nitrogen, respectively, the most prevalent types of free radicals seen in biological systems.
The production of these compounds at low to moderate levels is expected in farm animals as they are exposed to challenges under extensive or rangeland production systems.
However, in high amounts, these reactive radicals may be hazardous to the animals. These radicals can destroy biological macromolecules, generate primary and secondary chemicals that can increase the production of radicals, and are harmful to the metabolic processes of cellular or tissue systems.
Antioxidants and animal health
Animal health benefits from natural antioxidants, such as carotenoids and vitamins A, E, and C. They serve as natural antioxidants to eliminate dangerous free radicals generated by normal cellular function and external stresses, preserving the structural integrity of immune cells. They may even modulate cellular activities.
Antioxidants are crucial to animal health because they boost immunity. Farm animals frequently experience malnutrition or undernutrition, which is sometimes caused by long droughts or adverse seasonal circumstances that affect their daily food intakes and nutritional intakes, i.e. a balanced diet. This can result in slower growth or worse health, which might then induce oxidative distress. However, depending on seasonal fluctuations, outdoor and/or organic production techniques for pig and poultry production may suffer the same difficulties.
Through a number of events, oxidative stress disrupts cellular or muscle functioning, causing the body to undergo a number of physiological or pathological alterations that impact the body's energy metabolism and nutritional partition. This result in decrease in animal performance and productivity. For instance, it has been demonstrated that oxidative distress has a detrimental effect on the somatic cell counts in milk as well as several preservatives and sensory properties of meat.
Oxidative distress can result in bacterial infections in the stomach in weaned piglets and broiler chickens, which can cause inflammation and low feed efficiency because of decreased gut function. An imbalance between the generation of free radicals and their elimination by antioxidant defenses causes oxidative stress.
The physiological processes of the body require just a small quantity of reactive oxygen species (ROS), but an excess leads to oxidative damage in molecules, adversely affecting the DNA and proteins of the cells as well as leading to the lipid peroxidation of cellular membranes.
Highly reactive free radicals are produced during regular cellular metabolism, as well as when environmental pollutants and drugs are ingested or inhaled. When these free radicals accumulate, they have the power to damage nuclear DNA, enzymes, and cellular membrane integrity.
Antioxidants protect cells' structural and functional integrity by stabilizing these extremely reactive free radicals. Antioxidants are therefore crucial for the wellbeing and productivity of animals. Antioxidants are therefore crucial for the wellbeing and productivity of animals.
The carotenoids as well as vitamins A, C, and E are among these naturally occurring antioxidant vitamins. Studies have demonstrated that these antioxidants can control an animal's host defense responses whether acting singly or in combination.
There is a definitive relationship between the onset of several illnesses in animals and a decline in the antioxidant level. Additionally, oxidative stress has a role in a variety of pathological conditions that harm animal welfare, health, and productivity standards.
In reality, during some productive stages, animals must cope with physiological changes, such as farrowing and lactating, or environmental changes, such as weaning or high temperatures, and a number of forms of stress lead to a reduction in the antioxidant status.
Uses of antioxidants in animal nutrition
The level of Vitamin E in meat can both be improved and the degree of lipid peroxidation in meat can be reduced by an animal's antioxidant status.
Antioxidants are being used more often in animal nutrition due to the current trend of producing diets with components high in polyunsaturated fatty acids (PUFAs), which are extremely vulnerable to lipid peroxidation.
Based on their ability to stop lipid peroxidation and oxidative rancidity during the manufacture, processing, and storage of animal feeds, premixes, and fats, antioxidants are employed as additives to extend their shelf life.
The nutritional value of the feed is noticeably reduced by the oxidation of fats and oils since less energy is supplied to the animal that consumes them. In the same manner, oxidized feed includes a lot of free radicals and peroxides that might harm animals.
Antioxidants helps in keeping premixes, feed, animal fats, and flours, healthy and fresh also preserved them for long period of time, as the antioxidants helps to protect them from the damages caused by oxidation, keeping their sensory characteristics intact, thus reduce their discoloration and rancidity.
Antioxidants are used in animal nutrition to maintain the feed's sensory properties and stop the loss of vital nutrients such as vitamins, amino acids, and pigments. Alpha tocopherol (Vitamin E) which is a component of Tocopherols (Vitamin E) has its biological importance. It has been demonstrated that adding various amounts of d-alpha tocopherol to ruminants' diets has favorable benefits by lowering the prevalence of illnesses.
Antioxidant vitamin supplements given to dairy cows have helped to lower mastitis infection rates. Because there is no accelerated oxidation of the protein metmyoglobin, which gives meat its organoleptic qualities, The meat quality of the slaughtered animals has also increased with vitamin E treatment. This is because the color of the meat is maintained compared to that of animals that have not received the supplement.
Antioxidants have been employed in food processing for a very long time, however its addition in animal feed may be a more effective strategy to increase oxidative stability, sensory qualities and the antioxidant nutritional value of feed, while being more economical.
Antioxidant added feed consumption slows the production of metmyoglobin in meat intended for human consumption. and extend the period when the muscle surface shows no evidence of discoloration.
Antioxidants are necessary to maximize animal yields for livestock production, not only to boost economic output but also to improve product quality (milk, meat, and eggs) and customer safety.
Authors:
Dr. Lipika Sarma, Dr. Anjali, Dr. Amit Kumar, Dr. Priyanka M. Kittur
Division of Physiology and Climatology,
ICAR-Indian Veterinary Research Institute, Izzatnagar-243122, India
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