Effect of n-3 fatty acids on immune function in broiler chickens

Abstract

There is interest in the enrichment of poultry meat with long-chain n-3 polyunsaturated fatty acids in order to increase the consumption of these fatty acids by humans. However, there is concern that high levels of n-3 polyunsaturated fatty acids may have detrimental effects on immune function in chickens. The effect of feeding increasing levels of fish oil (FO) on immune function was investigated in broiler chickens. Three-week-old broilers were fed 1 of 4 wheat-soybean basal diets that contained 0, 30, 50, or 60 g/kg of FO until slaughter. At slaughter, samples of blood, bursa of Fabricius, spleen, and thymus were collected from each bird. A range of immune parameters, including immune tissue weight, immuno-phenotyping, phagocytosis, and cell proliferation, were assessed. The pattern of fatty acid incorporation reflected the fatty acid composition of the diet. The FO did not affect the weight of the spleen, but it did increase thymus weight when fed at 50 g/kg (P < 0.001). Fish oil also lowered bursal weights when fed at 50 or 60 g/kg (P < 0.001). There was no significant effect of FO on immune cell phenotypes in the spleen, thymus, bursa, or blood. Feeding 60 g/kg of FO significantly decreased the percentage of monocytes engaged in phagocytosis, but it increased their mean fluorescence intensity relative to that of broilers fed 50 g/kg of FO. Lymphocyte proliferation was significantly decreased after feeding broiler chickens diets rich in FO when expressed as division index or proliferation index, although there was no significant effect of FO on the percentage of divided cells. In conclusion, dietary n-3 polyunsaturated fatty acids decrease phagocytosis and lymphocyte proliferation in broiler chickens, highlighting the need for the poultry industry to consider the health status of poultry when poultry meat is being enriched with FO.

Broylerlerde Diyetteki Yağ Kaynaklarının Performans, Serum Kortikosteron Düzeyi, Antikor Titresi ve IFN-γ Gen Ekspresyonu Üzerine Etkileri

“…Another study revealed that inclusion of soybean oil in the diet could induce significant increases in serum corticosterone level. These results agree with studies that found that on weight of bursa Fabricius [29] , but it was not consistent with its effect on the weight of other organs (30). The results of this study indicated that the addition of that the addition of fish oil and soybean oil to the diet may be resulted in better improvement of immune response and performance in broiler chickens.…”

Effect of feeding of 5% prefermented cereal-based bioproduct enriched with γ-linolenic acid on production indicators, chemical composition, fatty acid profile and lipid oxidation of broiler meat

“…Therefore, income of fatty acids such as EPA and DHA by food is insufficient. An alternative source of the long-chain n-3 PUFA can be poultry meat if it could be enriched with appropriate fatty acids (Al-Khalifa et al 2012). The enrichment of broiler chicken meat with PUFA is a viable means of increasing PUFA consumption in European diets as intake of broiler chicken meat in the population is high (Rymer et al 2010).…”

Enrichment of Poultry Diets with Polyunsaturated Fatty Acids (PUFA) for Human Consumption

“…However, it is not clear whether this concern is justified, since some studies show no effect [15], some show a detrimental effect [16] while some show an improvement [16,17] in chicken immune response following feeding of n-3 PUFA.…”