VITAMIN E (TOCOPHEROL) DEFICIENCY IN POULTRY

VITAMIN E (TOCOPHEROL) DEFICIENCY IN POULTRY

INTRODUCTION

Fats play a pivotal role in the absorption of fat-soluble vitamins A, D, and E within the avian digestive system. Among these, vitamin E emerges as a crucial nutrient with many functions, primarily recognized for its antioxidant properties. Beyond its antioxidative role, vitamin E extends its influence to the preservation of other essential vitamins such as A, D, and fatty acids. This symbiotic relationship underscores its indispensable nature in avian nutrition. Moreover, vitamin E exhibits a complementary interaction with selenium, another vital micronutrient. Deficiency of vitamin E in hens manifests in various negative outcomes, notably leading to embryo mortality during incubation due to impaired blood vessel formation, typically observed on the 4th day of incubation. Additionally, administering vitamin E post-vaccination has been correlated with heightened antibody titers, emphasising its immunomodulatory effects. This interconnection between vitamin E, embryonic development, and immune response underscores the critical importance of ensuring adequate levels of this essential nutrient in poultry diets for optimal health and performance.

VITAMIN E (TOCOPHEROL) DEFICIENCY IN POULTRY

ETIOLOGY

Vitamin E and the selenium-containing enzyme glutathione peroxidase prevent cell membrane destruction caused by peroxides and other powerful oxidants produced as metabolic by-products. There is evidence that vitamin E, selenium, and

sulphur-containing amino acids perform separate functions but still act together to prevent The accumulation of harmful peroxides in tissue. Peroxides are derived, in part, From polyunsaturated acids in feeds.

DISEASES CAUSED BY DEFICIENCY OF VITAMIN E

1. Avian encephalomalacia

The disease is commonly seen in 2 to 6-week-old birds. It is a nervous syndrome characterised by ataxia, sudden prostration with legs outstretched and Toe flexed, lack of coordination in movement, disequilibrium, lateral Twisting of the head with paralysis and falling on the back

2. Exudative diathesis

Under This condition edema of the subcutaneous Tissue later turns green due to lysis of blood Birds develop moderate anaemia and haemorrhages in the breast, Thigh, intestines and gizzard The lesions may be seen in association with muscular degeneration. The chicks stand with their legs apart Edematous subcutaneous Tissue contains hyaline vascular lesions and haemorrhages. In laying hens The Thigh muscle is more susceptible to deficiency lesions Than The breast muscle and shows degenerative muscle fibres including calcium deposits vascular lesions and haemorrhages. Distension of the pericardium and sudden death have been noted. Vitamin E deficiency in the presence of adequate dietary selenium does not result in severe signs of exudative diathesis.

3. Muscular dystrophy

When vitamin & deficiency is accompanied by a sulphur amino acid deficiency, chicks show signs of nutritional myopathy, particularly of the breast muscle. The disease is common in 4 and 8-week-old birds. White, necrotic areas of muscle are seen in the breast muscle with white streaks in normal-coloured muscle. The condition affects all muscles of the body including The gizzard and heart muscle.

NECROPSY

· Softening and swelling of the cerebellum

. Haemorrhages are seen in the cerebellum and medulla oblongata

. Necrosis and oedema with haemorrhages at the periphery

TREATMENT

Recommended vitamin E levels are 30 to 150 mg/kg in the diet Be sure an antioxidant (0,25kg of BHT or santoquin per 1000 kg of feed) is in the feed if storage is long or environmental Temperatures are high.