The effect of dietary oils [menhaden (MO), flax (FL), palm (PO), and sunflower oils (SF)] with added tocopherols on the tocopherol deposition, fatty acid composition, and thiobarbituric acid (TBA) values of egg or tissues (liver, adipose tissue, white meat, and dark meat) were examined. Addition of tocopherols increased (P < 0.05) the total egg or tissue tocopherol content. The enhancement of total tocopherols in the different tissues in the order of magnitude were egg yolk > liver > adipose tissue > dark meat > white meat. Dark meat contained higher (P < 0.05) total tocopherols than white meat. Dietary MO or FL resulted in a significant (P < 0.05) incorporation of C20:5 n-3 and c22:6 n-3 with a concomitant reduction in C20:4 n-6 in liver, egg, white meat and dark meat. Dietary SF resulted in a significant (P < 0.05) incorporation of C18:2 n-6 and C20:4 n-6 in all the tissues. Addition of PO did not result in any change in the yolk saturated fatty acid content. The content of monounsaturated fatty acids were greater (P < 0.05) in all the tissues from PO diets than in diets with other oils. Dietary tocopherols resulted in a significant increase (P < 0.05) in the content of C20:5 n-3 and C22:6 n-3 in the yolk, adipose tissue, and white meat from birds fed MO + T diets. Inclusion of tocopherols resulted in a significant (P < 0.05) reduction in TBA values in eggs, in liver for MO and FL diets, and in dark and white meat for the MO diet. Tocopherol supplementation did not result in any change in TBA values in the PO diet.

Single Comb White Leghorn laying hens were fed diets containing 8 and 16% ground flax seed or 16% ground canola seed and were compared with birds fed a wheat and soybean control diet. Levels of omega-3 fatty acids in the egg yolk were monitored, and fertilized eggs were incubated after a plateau of omega-3 fatty acid level was reached. Fatty acid analyses were conducted on brain tissues of embryos at 15, 17, and 19 days of incubation and on newly hatched chicks. Fatty acid composition of plasma of the chicks was also determined. As compared with the controls, the omega-3 fatty acid content of eggs from hens fed flax and canola seed increased significantly (P<05), and the brain tissue of embryos and chicks contained significantly (P<.05) more omega-3 fatty acids, predominantly docosahexaenoic acid (C22 ; 6ai3)-T^ plasma of the chicks from hens fed flax seed contained significantly (P<05) more omega-3 fatty acids than those fed the control diet. The arachidonic acid (C20:4

Chicken egg yolk antibody (IgY) raised against Salmonella enteritidis or Salmonella typhimurium was found in highly specific activity levels by ELISA. S. enteritidis- and S. typhimurium-specific IgY powder, prepared by freeze-drying the egg yolk water-soluble fraction, contained 15.5 and 10.0% of specific IgY, respectively. Anti-S. enteritidis IgY cross-reacted 55.3% with S. typhimurium. The cross-reactivity of anti-S. typhimurium IgY with S. enteritidis was 42.4%. Salmonella-specific IgY was demonstrated to inhibit Salmonella growth in liquid medium. The growth rate of S. enteritidis incubated with S. enteritidis-specific IgY was fourfold less than that of the control group during a 4-to-6-h incubation. Cell counts of S. typhimurium incubated with S. typhimurium-specific IgY were reduced by 1.6 log cfu/mL in comparison to that of the control group after 6 h of incubation. The specific binding activity of IgY was further evaluated by using immunofluorescence and immunoelectron microscopy. It was found that Salmonella-specific IgY could bind to the antigens expressed on the Salmonella surface, resulting in structural alterations of the bacterial surface.

Single Comb White Leghorn laying hens were fed diets high in oleic, linolenic, or linoleic acid prepared by incorporation of high oleic acid sunflower seed (HOAS), full-fat flax seed (FLAX), or regular high linoleic acid sunflower seed (HLAS), respectively, to investigate the effects of dietary fats on the fatty acid compositions of major lipid classes of chicken eggs. Egg production, Haugh units, specific gravity, and yolk total lipid content were measured. After 3 wk of feeding, the fatty acid compositions of yolk total lipids, triglycerides, phosphatidylcholine (PC), and phosphatidylethanolamine (PE) were measured by gas chromatography. Dietary treatments had no effect on egg production, Haugh units, specific gravity, or yolk total lipid content. Feeding HOAS increased yolk oleic acid by 17%, and the change was only in triglycerides. The increases of yolk linoleic and arachidonic acids upon HLAS feeding were distributed evenly among triglycerides and PC, with moderate effect in the PE fraction. The enrichment of linolenic acid in eggs from the FLAX regime was mainly in triglycerides. The longer chain n-3 fatty acids, such as eicosapentaenoic, dososapentaenoic, and docosahexaenoic acids, were deposited exclusively in phospholipids, particularly in PE. The contents of the longer chain n-3 fatty acids in PE were three to seven times those in PC, indicating a preferential incorporation of these fatty acids into PE.

The effects of fat source on immune response of the offspring of the Single Comb White Leghorn laying hens were investigated. The laying hens were fed for 6 wk with a wheat-soybean meal basal diet with added sunflower oil (SO), animal oil (AO), linseed oil (LO), or menhaden fish oil (FO) at 5% (wt/wt). Upon hatching, the chicks (30/group) were given the same types of diets for 8 wk. The dietary SO, AO, and LO provided different n-6 to n-3 polyunsaturated fatty acids (PUFA) ratios. The FO and LO had ratios of n-6 to n-3 PUFA that were close but had different components of n-3 PUFA. The results demonstrated that the chicks fed LO or FO had significantly lower (P < 0.05) splenocyte proliferative response to ConA than the chicks fed SO or AO at either 4 wk or 8 wk of age, with a stronger (P < 0.05) suppressive effect produced by LO at 4 wk. A significantly lower (P < 0.05) splenocyte response to PWM was produced by the chicks fed AO, LO, and FO compared with the chicks fed SO at 8 wk. The thymus lymphocyte proliferation in response to ConA at 4 wk was lower (P < 0.05) in the chicks fed AO, LO, and FO than in the chicks fed SO. Both LO and FO elevated (P < 0.05) the proportion of IgM+ lymphocytes in spleen, but only FO increased (P < 0.05) the serum IgG concentration. The LO elevated (P < 0.05) the percentage of CD8+ T-lymphocytes but not the ratio of CD4+ to CD8+ cells (P > 0.05) in spleen. Growths of thymus, spleen, and bursa were impacted significantly (P < 0.05) by the amount of dietary PUFA, the ratio of n-6 to n-3 fatty acids, and n-3 PUFA components.