Department of Animal Sciences, University of Florida, Gainesville 32611, FL, USA.
J Anim Sci. 2010 Jan;88(1):248-57. doi: 10.2527/jas.2009-2253. Epub 2009 Sep 25.
To determine the effect of different sources of dietary n-3 fatty acids (FA) on plasma and red blood cell (RBC) FA composition and immune response, 18 Quarter Horse yearlings were randomly and equally assigned to 1 of 3 treatments: encapsulated fish oil (n = 6), milled flaxseed (n = 6), or no supplementation (control, n = 6). Fish oil contained 15 g of eicosapentaenoic acid (C20:5n-3) and 12.5 g of docosahexaenoic acid (C22:6n-3), and flaxseed contained 61 g of alpha-linolenic acid (C18:3n-3) per 100 g of FA. Horses had free access to bahiagrass pasture during the active growing season and were individually fed a grain mix concentrate at 1.5% BW/d. Fish oil and flaxseed were mixed into the concentrate in amounts to provide 6 g of total n-3/100 kg of BW. Horses were fed their respective treatments for 70 d. Blood samples were obtained to determine plasma and RBC FA composition and for isolation of peripheral blood mononuclear cells. Peripheral blood mononuclear cells were stimulated with concanavalin A and phytohemagglutinin (PHA) to determine lymphocyte proliferation and were challenged with lipopolysaccharide to determine PGE(2) production. In vivo inflammatory response was assessed on d 70 by measuring skin thickness and area of swelling in response to intradermal injection of PHA. Treatment did not affect BW gain, which averaged 0.6 +/- 0.03 kg/d. Horses fed fish oil had greater (P < 0.05) proportions of eicosapentaenoic acid, docosahexaenoic acid, and sum of n-3 in plasma and RBC compared with those in the flaxseed and control treatments. In addition, plasma arachidonic acid was greater (P < 0.05) and plasma linoleic and alpha-linolenic acids were less (P < 0.05) in the fish oil treatment compared with the flaxseed and control treatments. Dietary treatment did not affect lymphocyte proliferation or PGE(2) production. Across treatments, the peak increase in skin thickness was observed 4 to 8 h after PHA injection. At 4 h postinjection, horses fed fish oil and those fed flaxseed had a greater increase in skin thickness than those in the control treatment (P < 0.05) and horses fed fish oil had a larger area of swelling than those in the control treatment (P < 0.05). Skin thickness remained greater (P < 0.05) in horses fed flaxseed than in control horses 6 h after injection. Although fed to supply a similar amount of n-3 FA, fish oil had a greater impact on plasma and RBC n-3 FA content than did flaxseed. However, supplementing horses with both fish oil and flaxseed resulted in a more pronounced early inflammatory response to PHA injection as compared with nonsupplemented horses.
为了确定不同来源的膳食 n-3 脂肪酸（FA）对血浆和红细胞（RBC）FA 组成和免疫反应的影响，18 匹夸特马驹被随机平均分为 3 个处理组之一：包封鱼油（n=6）、磨碎亚麻籽（n=6）或不补充（对照组，n=6）。鱼油含有 15 克二十碳五烯酸（C20:5n-3）和 12.5 克二十二碳六烯酸（C22:6n-3），亚麻籽每 100 克 FA 含有 61 克α-亚麻酸（C18:3n-3）。马驹在活跃的生长季节可自由采食百喜草牧场，并每天按体重的 1.5%单独饲喂精饲料混合物。鱼油和亚麻籽以提供每 100 公斤 BW 6 克总 n-3 的量混合到精饲料中。马驹接受各自的处理 70 天。采集血样以确定血浆和 RBC FA 组成，并分离外周血单核细胞。外周血单核细胞用刀豆球蛋白 A 和植物血凝素（PHA）刺激以确定淋巴细胞增殖，并通过脂多糖刺激以确定 PGE（2）产生。在第 70 天通过测量 PHA 皮内注射后皮肤厚度和肿胀面积来评估体内炎症反应。处理不会影响 BW 增加，平均为 0.6 +/- 0.03 kg/d。与亚麻籽和对照组相比，饲喂鱼油的马血浆和 RBC 中二十碳五烯酸、二十二碳六烯酸和 n-3 总和的比例更高（P <0.05）。此外，与亚麻籽和对照组相比，血浆花生四烯酸更高（P <0.05），血浆亚油酸和α-亚麻酸更低（P <0.05）。膳食处理对淋巴细胞增殖或 PGE（2）产生没有影响。在各处理组中，PHA 注射后 4 至 8 小时观察到皮肤厚度的峰值增加。在注射后 4 小时，饲喂鱼油和亚麻籽的马比对照组马（P <0.05）的皮肤厚度增加更大，并且饲喂鱼油的马比对照组马的肿胀面积更大（P <0.05）。注射后 6 小时，饲喂亚麻籽的马的皮肤厚度仍高于对照组马（P <0.05）。尽管以供应相似量的 n-3 FA 进行喂养，但鱼油对血浆和 RBC n-3 FA 含量的影响大于亚麻籽。然而，与不补充的马相比，同时给马补充鱼油和亚麻籽会导致对 PHA 注射的早期炎症反应更为明显。
