H Al-Khalaifa
Kuwait Institute for Scientific Research, Kuwait
Title: Do immune organ weights indicate immunomodulation of polyunsaturated fatty acids?
Biography
Biography: H Al-Khalaifa
Abstract
The main immune organs in poultry are the thymus, spleen and bursa of Fabricius. During an immune response, mature lymphocytes and other immune cells interact with antigens in these tissues. Consequently, the mass of these organs can in some cases indicate immune status. It was observed that feeding laying chickens on diets rich in PUFA, especially n-3 PUFA, promoted the growth of the thymus, spleen and bursa up to 4 weeks of age. From the age of 4 weeks onwards, the immune tissue weight started to be suppressed and the bursa was degenerated in the course of 4 to 8 weeks of age. The objective of the current study is to investigate the effect of feeding flaxseed on immune tissue weights. Cobb 500 broiler chickens were fed flaxseed at 15%, the control diet did not contain any flaxseed. Values are presented as a percentage of body weight to account for differences in weights between different birds. Results showed that dietary supplementation with flaxseed did not affect the weights of the spleens of broiler chickens. However, it significantly lowered bursa weights (p<0.01), compared to the control diet. In addition, the bursae were thinner in appearance compared with bursii from chickens fed the control diets. In conclusion, dietary supplementation with flaxseed did not affect the growth of the spleen of the chickens. Conversely, it was reported in some studies that feeding PUFA to chickens and mice results in increased spleen weights. However, chickens fed a diet containing flaxseed had smaller and thinner bursii than chickens fed the control diets (P=0.001). This modulation in the weight of immune organs may indicate immunomodulation effect of fatty acids in flaxseed. More investigation studies need to be applied to shed light on the mechanism behind this immunomodulation.