Influence of long-term chitosan feeding of laying hens

Under insufficient vitamin content in a diet of laying hens in compliance with lowered vitamins A, E and carotenoids content in an egg yolk acid- and water-soluble chitosan feeding (10 and 20 mg per 1 kg body mass) within 6-9 months did not render appreciable influence on these vitamins egg content. Long-term inclusion of a sorbent in a forage was not reflected in vitamin B2 level in a whole egg, blood serum and tissues of hens. Chitosan intake didn't lead to total lipids and phospholipids concentration in a whole egg. Under 15 per cent decrease of the sum of polyunsaturated fat acids its administration lead to 24 per cent increase of omega-3 polyunsaturated fat acids in the whole egg.     

Influence of dietary rapeseed meals and selenium on egg production and egg tainting in laying hens

In 3 experiments 152 hens of differing strains were fed diets containing 0, 50 or 100 g Span, Canadian or European rapeseed meal per kg. Two strains, Shaver 288 and Babcock B300, laid white-shelled eggs while three other strains, Shaver 585, Warren 14 and Thomber 404 laid brown-shelled eggs. Egg production performance was not significantly affected by the inclusion of rapeseed meal in the diet. However the strains laying brown-shelled eggs laid a high proportion of tainted eggs when rapeseed meal was included in the diet. All rapeseed meals led to a similar degree of tainting. Supplementing the diets with 1 or 2 mg selenium per kg did not significantly affect the incidence of tainting. Shell thickness, albumen height and Haugh unit were unaffected by the presence of rapeseed meal in the diet, and yolk colour was improved by the inclusion of Canadian and European rapeseed meals. On the basis of these and other findings it is recommended that rapeseed meal be omitted from diets at least for hens that lay brown-shelled eggs until the taint problem has been solved.     

Effects of dietary black cumin seed (Nigella sativa L.) on performance,egg traits,egg cholesterol content and egg yolk fatty acid composition in laying hens

BACKGROUND: The objective of this study was to determine the effects of dietary black cumin seed on performance, egg traits, egg cholesterol content and egg yolk fatty acid composition in laying hens during a 12 week period. For this purpose a total of 160 Lohmann Brown laying hens 36 weeks of age were allocated to four dietary treatments with one control group and three treatment groups. Black cumin seed (Nigella sativa L.) was used at the level of 5, 10 and 15 g kg^?1 in the diets of the first, second and third treatment groups, respectively. RESULTS: Dietary treatments did not significantly affect body weight, feed intake, egg production, egg quality characteristics and blood parameters. Diets containing 10 and 15 g kg^?1 black cumin seed increased egg weight (P < 0.01), improved feed efficiency (P < 0.01) and decreased egg yolk cholesterol, saturated fatty acids (% of total fatty acid methyl esters) and the ratio of saturated to unsaturated fatty acids (P < 0.05) compared to the diet of control group. CONCLUSION: Dietary black cumin seed at the level of 10 and 15 g kg^?1 had beneficial effects on egg weight, feed efficiency, egg cholesterol content and egg yolk fatty acid composition. Therefore it can be used at the level of 10 and 15 g kg^?1 in the diets of laying hens. Copyright © 2009 Society of Chemical Industry     

Effects of dietary yeast autolysate (Saccharomyces cerevisiae) on performance,egg traits,egg cholesterol content,egg yolk fatty acid composition and humoral immune response of laying hens

BACKGROUND: The objective of this study was to determine the effects of dietary yeast autolysate on performance, egg traits, egg cholesterol content, egg yolk fatty acid composition, lipid oxidation of egg yolk, some blood parameters and humoral immune response of laying hens during a 16 week period. A total of 225 Hyline Brown laying hens, 22 weeks of age, were allocated equally to one control group and four treatment groups. Yeast autolysate (Saccharomyces cerevisiae, InteWall) was used at levels of 1, 2, 3 and 4 g kg^?1 in the diets of the first, second, third and fourth treatment groups respectively. RESULTS: Dietary treatments did not significantly affect body weight, feed intake and egg traits. Yeast autolysate supplementation increased egg production (P < 0.001) and egg weight (P < 0.001) and improved feed efficiency (P < 0.05). Yeast autolysate at levels of 2, 3 and 4 g kg^?1 decreased egg yolk cholesterol level as mg g^?1 yolk (P < 0.01) and blood serum levels of cholesterol and triglyceride (P < 0.05) and increased antibody titres to sheep red blood cells (P < 0.01). Total saturated fatty acids and the ratio of saturated/unsaturated fatty acids increased (P < 0.01) and total monounsaturated fatty acids (P < 0.001) decreased with yeast autolysate supplementation. CONCLUSION: Dietary yeast autolysate at levels of 2, 3 and 4 g kg^?1 had beneficial effects on performance, egg cholesterol content and humoral immune response. It is concluded that 2 g kg^?1 yeast autolysate will be enough to have beneficial effects in laying hens. Copyright © 2010 Society of Chemical Industry     

低聚壳聚糖对蛋鸡脂类代谢及鸡蛋品质的影响

试验旨在研究低聚壳聚糖对蛋鸡脂类代谢及鸡蛋品质的影响。结果表明,低聚壳聚糖使第4周蛋鸡血清甘油三酯、低密度脂蛋白胆固醇和极低密度脂蛋白胆固醇含量分别降低了40.90%(P<0.05)、49.02%(P<0.01)和34.76%(P<0.05),脂蛋白脂肪酶、肝脂酶和总酯酶活性分别提高了10.38%(P>0.05)、42.89%(P<0.05)和30.24%(P>0.05);第8周脂蛋白代谢酶活性也有所提高。低聚壳聚糖对蛋鸡腹脂率、鸡蛋脂肪含量和鸡蛋品质无影响(P>0.05)。     

The potential of cholecalciferol and 25-hydroxyvitamin D3 enriched diets in laying hens,to improve egg vitamin D content and antioxidant availability

Sixty Hy-line brown hens were randomly assigned to four barns (n = 4) to investigate the effects of cholecalciferol (vitamin D₃) versus 25-hydroxyvitamin D₃ (25-OH-D₃) enriched diets on egg vitamin D concentration, antioxidant activity and egg quality parameters. Experimental design was a 4 × 4 Latin square consisting of 4 experimental treatments and 4 experimental periods. The treatments were (1) 1500 IU of vitamin D₃ (2) 3000 IU of vitamin D₃ (3) 1500 IU of vitamin D₃ and 37.5 μg of 25-OH-D₃ (4) 75 μg of 25-OH-D₃ per kg of feed. Hens offered 75 μg of 25-OH-D₃ had a higher (P < 0.05) total vitamin D egg yolk content (5.06 μg/egg), and antioxidant activity compared to other dietary treatments. The results demonstrates that the enrichment of hen diets with 25-OH-D₃ may be a useful approach and may contribute between 25 and 33% towards total vitamin D daily requirements while also improving antioxidant status of eggs.Industrial relevanceVitamin D deficiency is now regarded as a major issue in northern Europe and has been described as a pandemic. A growing interest in vitamin D food fortification in northern Europe to satisfy the current dietary intake recommendations has been observed. The use of a bio-addition approach for increasing vitamin D intake through biofortification of livestock feeds attracts attention. Enrichment of the hen's diet with vitamin D may also supply additional benefits of increasing antioxidant activity. This increase in antioxidant activity may have the ability to increase food quality and extend the shelf life. This study explores the effect of vitamin D enriched diets fed to laying hens on vitamin D egg yolk content and antioxidant activity in the egg. These enriched diets could demonstrate that enrichment of hen diets with 25-hyroxvitamin D₃ may be a useful approach for tackling low vitamin D intakes and improving antioxidant capacity of eggs.     

Ovarian autoimmunity in relation to egg production in laying hens

The aim of this study was to determine whether anti-ovarian autoantibodies appear in the circulation of laying hens and whether the concentrations of these antibodies change with respect to ageing and egg laying rate. Autoantibodies to ovarian tissues in the circulation of aged (aged approximately 670 days) White Leghorn hens with low (< 50%) and high (> 90%) egg laying rates were examined by ELISA and western blotting. Young laying hens (aged 185 days) with > 95% egg production were used as controls. The results of the ELISA indicated that IgG, which bound to the ovary and small white follicles, was present in the circulation of old laying hens. More hens that laid few eggs had circulatory autoantibodies to the ovary and small white follicles, as determined by the cut-off value in ELISA (mean absorbance + 2 SD of young laying hens), than did hens that laid greater numbers of eggs, and the concentration of IgG was significantly higher in the hens that laid few eggs. In contrast, when the muscle proteins were used as antigens there were no significant differences in the absorbance values among low and high laying frequency old hens or young hens. Western blotting revealed many bands of immunoprecipitates formed by ovarian antigens and antibodies in the serum of old hens, indicating the presence of many binding sites for circulatory IgG in ovarian tissues. These results indicate that antibodies to ovarian tissues appear in the circulation of laying hens during ageing, and that the concentration of these autoantibodies is related inversely to the rate of egg laying by hens.     

Effects of Lactobacillus cultures on performance of laying hens,and total cholesterol,lipid and fatty acid composition of egg yolk

BACKGROUND: The use of antibiotic growth promoters in animal feeds is not approved for laying hens in many countries, and economically feasible biological measures which include probiotics are developed to improve hen performance. The present study investigated the effects of probiotics on hen performance for a 48‐week period and the cholesterol, total lipid and fatty acid composition of egg yolk at 24, 28 and 32 weeks of age. RESULTS: Egg weight of Lactobacillus culture (LC)‐fed hens was significantly (P < 0.05) greater than that of control hens throughout the laying period. From 20 to 44 weeks of age, LC‐fed hens produced a significantly (P < 0.05) lower percentage of small eggs and a higher percentage of large eggs, and from 45 to 68 weeks of age a significantly (P < 0.05) lower percentage of medium eggs and a higher percentage of large and extra‐large eggs than control hens. Significantly (P < 0.05) less cholesterol was found in egg yolks of hens fed LC at 24 and 28 weeks of age, but not at 32 weeks of age. The total lipid content and the fatty acid composition of egg yolks were similar between the treatments at 24, 28 and 32 weeks of age, except for stearic acid (C_{18 : 0}), which was significantly reduced in the egg yolk of LC‐fed hens at 28–32 weeks of age. CONCLUSION: The greatest benefit of LC was in increasing egg weight and improving egg size by influencing a shift from small and medium to large and extra‐large eggs. Copyright © 2008 Society of Chemical Industry     

Effect of garlic powder on the performance,egg traits and blood parameters of laying hens

This study was conducted to investigate the effects of garlic powder on the performance, egg traits and blood parameters of laying hens. One hundred and sixty‐two SHSY‐type brown layers aged 21 weeks were chosen at random from a large flock. They were allocated to three dietary treatments. Each treatment comprised six replicates of nine layers in groups of three. The diets were supplemented with 0, 5 and 10 g kg^?1 garlic powder. The experimental period lasted 22 weeks. Garlic powder addition did not significantly affect body weight, egg production, feed consumption, feed efficiency, egg shell index, egg breaking strength, egg shell thickness, egg albumen index, egg yolk index, egg Haugh unit, egg yolk weight and serum protein concentration. Egg weight increased (P < 0.01) with garlic powder supplementation. There was a significant (P < 0.01) reduction in egg cholesterol concentration as mg g^?1 yolk when the dietary level of garlic powder was increased from 0 to 10 g kg^?1. Hen serum triglyceride (P < 0.05) and total cholesterol (P < 0.01) concentrations decreased with garlic powder supplementation. This study demonstrated that garlic powder addition increased egg weight and decreased egg yolk cholesterol concentration (mg g^?1 yolk) and serum triglyceride and cholesterol concentrations without adverse effects on performance and egg traits. Copyright © 2006 Society of Chemical Industry     

Influence of rapeseed cake, linseed cake and hemp seed cake on laying performance of hens and fatty acid composition of egg yolk

In hens the effects of expeller/cakes from rapeseed, linseed, and hemp seed were investigated on feed intake, laying performance and fatty acid composition of egg yolk. A total of 216 individually caged laying hens were allocated to nine dietary treatments (5, 10, 15 % cake) and fed for six laying months. For feed intake, egg mass production and feed-to-egg mass ratio at 15 % dietary cake level a significant lower performance was shown compared with the 5 and 10 % cake level groups. Also interaction was significant for all these parameters, indicating that the cake level acted differently for the three cakes. The egg mass production was lower in the linseed cake than in the hempseed groups and the hens fed the linseed cake needed significantly more feed per kg egg mass compared with both the other cakes tested. Increasing dietary level of all oil seed cakes lowered the yolk percentage and increased the egg white percentage. Increased dietary levels of all three oil seed cakes lowered the percentages of most saturated fatty acids and also the percentages of the monounsaturated fatty acids. The linoleic acid and the linolenic acid as polyunsaturated fatty acids were heightened by increasing the cake levels from 5 to 10 and 15 % in the diet. The results allow the conclusion that compound feeds with up to 10 % of cakes does not negatively influence the laying performance of hens and provides the possibility of the enrichment of yolk fat with polyunsaturated fatty acids.     

Rapeseed meal in rations for laying hens: A review of the effect on egg quality

The current role of rapeseed meal (RSM) as a source of protein for laying hens is discussed. The advantages of the use of meal from low glucosinolate rapeseed cultivars are emphasised. The effect of the inclusion of RSM in layer rations on egg quality is discussed with special reference to the problem of the fishy egg taint which occurs in the eggs of certain breeds of laying hen. The current understanding of the problem is outlined and potential solutions are offered, based upon plant and avian genetic manipulation or chemical treatment of the rapeseed meal.     

The effects of sources of supplemental fat on performance,egg quality,and fatty acid composition of egg yolk in laying hens

BACKGROUND: The objective of this study was to determine the effects of sources of supplemental fat on laying performance, egg quality, and fatty acid composition of egg yolk. RESULTS: Two hundreds Isa Brown layers were assigned randomly to be fed ad libitum a standard commercial layer feed (BD), basal diet plus 2% tallow (T), basal diet plus a mixture of 1% tallow and 1% flaxseed oil (MTFO), basal diet plus 2% sunflower oil (SO), or basal diet plus 2% flaxseed oil (FO), which were offered for 8 weeks. Each diet was given to five groups, each containing 10 hens. The feed efficiency and egg production were 2.78 and 53.51% for BD; 2.30 and 63.47% for T; 2.45 and 60.14% for MTFO; 2.29 and 64.30% for SO, and 2.62 and 61.18% for FO groups, respectively. Dietary fat supplementation affected the laying performance but had no significant effects on egg quality parameters. The fatty acid composition of egg yolk lipids were significantly affected by dietary fatty acid composition. The supplemental tallow increased palmitic fatty acid. The proportions of linoleic and arachidonic fatty acids in egg yolks for layers fed the SO diet were higher than in the BD group and those on diets containing other fats. Concentrations of oleic and omega‐3 fatty acids were the highest in layers fed the FO diet during the laying period. CONCLUSION: The results indicated that dietary animal and plant fats changed the fatty acid composition of egg yolk. Copyright © 2008 Society of Chemical Industry     

Effect of probiotic supplementation on laying hen diets on yield performance and serum and egg yolk cholesterol.

The effects of dietary supplementation of a commercial probiotic (BioPlus 2B) on daily feed consumption, egg yield, egg weight, specific gravity, body weight, feed conversion ratio, serum and egg yolk cholesterol, and serum trigylceride in layer hens were investigated. In 12 replicates, 480 27-week-old Brown-Nick layers were fed with diets containing 0, 250, 500 or 750 mg kg(-1) probiotic for 90 days. When compared with the controls, supplementation of 250, 500 and 750 mg kg(-1) probiotic increased egg production, but decreased the damaged egg ratio (p < 0.05), egg yolk cholesterol and serum cholesterol (p < 0.001) levels. In addition, serum triglyceride levels were reduced by using 500 and 750 mg kg(-1) probiotic supplementation (p < 0.001). Feed conversion ratios were positively affected by supplementation of 250 and 500 mg kg(-1) probiotic compared with controls (p < 0.05). There was no statistically significant difference between the control and all treatment groups on feed consumption, egg weight, specific gravity, body weight, and egg yolk weight.     

蛋类的不同加工工艺对脂肪、胆固醇含量的影响

蛋类通过醋泡、碱制等不同的加工工艺使之变成功能性食品醋蛋、松花蛋。通过测定其加工前后胆固醇、脂肪的含量,发现加工后胆固醇、脂肪含量大大低于加工前的含量。试验结果表明,不同醋处理鸡蛋中脂肪含量下降幅度在7.50%～11.69%;碱处理鹌鹑蛋、鸭蛋脂肪含量下降分别为34.34%、16.81%～35.28%;碱处理鹌鹑蛋、鸭蛋胆固醇含量下降分别为27.46%、48.93%～76.42%;醋处理鸡蛋中胆固醇含量下降幅度在13.02%～73.39%。     

Effects of housing system and age of laying hens on egg performance in fresh pasta production: pasta cooking behaviour

BACKGROUND: Very few studies concern the effects of layer housing systems and age on egg technological properties. Thus the aim of this work was to study the influence of these two factors on egg performance in fresh pasta production, focusing on pasta cooking behaviour. Samples of pasta subjected to analysis were prepared with eggs laid by Hy‐Line Brown hens (from 27 to 68 weeks old) housed in cage, barn and organic systems. RESULTS: Higher average values of weight increase and matter loss during pasta cooking were observed for samples prepared with eggs laid by older hens. Such cooking behaviour indicated the development of a weaker pasta protein network, resulting from a decrease in the quantity of albumen protein and an increase in fat content, which is due to the reduction in albumen/yolk ratio during hen aging. The housing system had a significant effect only on matter loss in cooking water, but differences between samples were so small as to be unlikely perceived by consumers. CONCLUSION: Both hen age and housing system significantly affected pasta cooking behaviour, but the greatest effect was exerted by the hen age. Copyright © 2010 Society of Chemical Industry     

酵母培养物对蛋鹌鹑产蛋性能及产蛋品质的影响

研究酵母培养物对蛋用鹌鹑产蛋性能及产蛋品质的影响。对照组饲喂基础日粮,低、中和高水平酵母培养物组在基础日粮的基础上分别添加0．1％、0．3％和0．5％酵母培养物。结果表明：中、高水平酵母培养物组能显著提高蛋鹌鹑的产蛋率、蛋壳强度和哈夫单位,显著降低蛋鹌鹑的料蛋比、次品蛋率和死淘率。说明酵母培养物能提高产蛋性能和一定程度的提高产蛋品质,酵母培养物的适宜添加水平为0．3％