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     

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     

Effects of L‐carnitine supplementation to diets with different fat sources and energy levels on fatty acid composition of egg yolk of laying hens

BACKGROUND: The present study was carried out to determine the effects of feeding diets with two different levels of metabolisable energy (ME) (11.51 or 10.88 MJ ME kg^?1 diet) and three different sources of fat (palm oil, sunflower oil or fish oil) with or without supplemental L ‐carnitine (0 or 500 mg kg^?1 diet) on the fatty acid (FA) composition of egg yolk and the passage of n3 polyunsaturated FAs to egg yolk in laying hens. RESULTS: The ∑n3, particularly C22:6n‐3, FA contents of egg yolk were significantly reduced by adding of L ‐carnitine (C2) to different fat sources (P < 0.01). The ratio of n6/n3 was reduced from 53.77 to 17.72 in eggs yolks when ME was lowered in the diet with C2‐sunflower oil (SFO) whereas it was enhanced from 2.19 to 9.31 in C2‐E2 (low energy) diet with fish oil (FO) (P < 0.001). The diet with E2 or C2 containing FO resulted in a decrease of the C22:5n‐3, C22:6n‐3 and ∑n3 FA contents of egg yolk (P < 0.001). On the other hand, supplementation of C2 to diets with SFO or palm oil (PO) caused to a decrease in the C22:6n‐3 and ∑n3 FA contents of egg yolk (P < 0.01). A significant increase of the ratio of n6/n3 in egg yolk can be seen by feeding with E2 diet by adding of C2 to all fat sources like in E1 (normal energy) diet (P < 0.001). CONCLUSION: Dietary treatments resulted in major changes in FA composition of egg yolk. The supplemental C2 in diet decreased the C22:5n‐3, C22:6n‐3 and ∑n3FA contents in egg yolk. The use of FO in diets with E2 significantly reduced the passage rate of C22:6n‐3 FA to egg yolk. Copyright © 2008 Society of Chemical Industry     

Effects of dietary microalgae,other lipid sources,inorganic selenium and iodine on yolk n‐3 fatty acid composition,selenium content and quality of eggs in laying hens

BACKGROUND: This aim of this study was to investigate the effects of supplementing laying hen diets with different n‐3 fatty acid sources (linseed oil, fish oil and microalgae) on egg quality and fatty acid profile. The addition of inorganic selenium (Se) and iodine (I) and their effects on egg characteristics and Se concentration were also evaluated. RESULTS: A significantly lower egg weight was found in the control group and in groups fed a diet containing fish oil or a diet containing microalgae plus Se and I. Yolks from all supplemented diet groups exhibited a significant reduction in n‐6 fatty acid content compared with the control group. The docosahexaenoic acid (DHA) content of yolks was higher (P < 0.01) in all supplemented diet groups. Selenium supplementation increased the Se concentration (P < 0.001) in eggs. CONCLUSION: The results of this study provide evidence that an improvement in egg weight and in the DHA content of yolks can be achieved by feeding hens a microalgae‐rich diet, which avoids the unpleasant flavours associated with fish oil supplementation. Dietary inorganic Se, especially in combination with I, can enhance the concentration of Se in eggs. Copyright © 2009 Society of Chemical Industry     

Effects of egg weight on egg quality characteristics

BACKGROUND: The experiment was carried out with total of 270 eggs, which were collected from a brown‐egg layer strain of Lohmann hens reared in a cage system. Collected eggs were categorized according to weight and classified as medium, large, extra‐large or jumbo. The purpose of the study was to determine the effect of egg weight on egg quality characteristics. RESULTS: The darkest shell color scales were noted in jumbo eggs. The redness of egg shell color in the medium egg was significantly lower than that of the other egg sizes (P < 0.05). Egg shell thickness (P < 0.05) was highest in medium egg (0.400 mm) and lowest in extra‐large egg (0.382 mm). Albumen height (AH) was significantly affected by egg weight (EW) (P < 0.01). Yolk height (YH) and yolk index (YI) increased with egg size. Breaking strength was highest in the medium‐weight egg. There were significant positive correlations between EW and AH, EW and YH, EW and YI, EW and yol color, EW and redness (a), but EW had significant negative correlations with ST in overall eggs. CONCLUSION: The darkest shell color (L‐a‐b) was noted in the jumbo egg. Albumen height and yolk height increased with egg weight. Increase in egg weight caused darkness in the yolk color scale. Copyright © 2008 Society of Chemical Industry     

Egg yolk fatty acid profile in relation to dietary fatty acid concentrations

BACKGROUND: The health benefits of n‐3 fatty acids have led to much research on manipulating the fatty acid composition of animal‐derived foods. In this study, two experiments were conducted to investigate the interaction of dietary fatty acids on egg yolk fatty acid concentrations. In experiment I, 32 dietary treatments with three replicates of three birds each were fed for 35 days. Diets were prepared by mixing one type of fish oil with four vegetable oils in different proportions. In experiment II, three different types and two levels of fish oil in combination with two vegetable oils were tested under the same conditions as in experiment I. RESULTS: In experiment I the results showed that the egg yolk saturated (SFA) and monounsaturated (MUFA) fatty acid concentration was determined by the dietary SFA, MUFA and 18:2n‐6 content. The egg 18:2n‐6 concentration was mainly explained by the dietary inclusion of 18:2n‐6 and negatively by the dietary MUFA content. The egg C18:3n‐3, C20:5n‐3 and C22:6n‐3 concentration is almost exclusively determined by their direct supply from the diet. The egg 20:4n‐6 concentration was inversely proportional to the long‐chain n‐3 polyunsaturated fatty acid content of the diet. The results of experiment II showed that the egg yolk C20:5n‐3 and C22:6n‐3 concentration was determined by both the level of dietary fish oil (1 or 2%) and the C20:5n‐3/C22:6n‐3 ratio in the fish oil. CONCLUSION: The results of this study demonstrated that the direct dietary supply of fatty acids is the most important factor determining the egg yolk fatty acid composition, in particular for the n‐3 fatty acids. The interaction effect from other dietary fatty acids was in general small. Copyright © 2011 Society of Chemical Industry     

Effects of dietary humate supplementation to broilers on performance,slaughter, carcass and meat colour

BACKGROUND: This experiment was designed to examine the effect of dietary humate supplementation primarily on pH and colour parameters of carcasses, breast fillets and drumsticks and, secondarily on performance and carcass characteristics in broilers. RESULTS: A total of 240 male broiler chicks (Ross‐308) were randomly allocated to four dietary treatments varying in supplemental humate level (0, 0.1, 0.2 and 0.3% for H₀, H₁, H₂ and H₃). Dietary humate supplementation did not affect performance traits and slaughter, hot carcass weights and yields. Carcass‐related variables (pH, L*, a*, b*, H* and C*) were responsive to the dietary treatments. The L*, a*, b*, and C* values for drumstick muscles were higher than those for breast muscles. Except for the L* value, meat colour parameters changed due to packaging. The a* value was higher and b* value was lower for vacuum packaged breast and drumsticks than for those aerobic packaged. Storage period affected colour parameters; while L*, b*, H* and C* values were higher for drumstick skin than for drumstick meat; the a* value was greater in drumstick meat than in skin. CONCLUSION: pH and colour parameters of carcasses, breast fillets and drumsticks of broilers were improved by dietary humate supplementation. However, responses of broiler performance and slaughter and carcass characteristics were minimal. Copyright © 2008 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％     

发酵全蛋蛋黄中的脂肪酸组成分析

采用气相色谱测定了发酵全蛋蛋黄中的总脂肪酸及游离脂肪酸的种类和含量,旨在考察发酵对蛋黄脂肪酸的影响。结果从发酵全蛋蛋黄中共检测到22种脂肪酸,其中饱和脂肪酸12种,单不饱和脂肪酸5种,多不饱和脂肪酸5种;共检测到10种游离脂肪酸,其中饱和游离脂肪酸6种,单不饱和游离脂肪酸2种,多不饱和游离脂肪酸2种。与水煮鸡蛋蛋黄相比,发酵全蛋蛋黄中的总脂肪酸及游离脂肪酸的种类均有增加,游离脂肪酸的含量从45.3mg/g增加到54.1mg/g,而总脂肪酸的含量则从273.7mg/g下降至245.2mg/g,说明发酵对蛋黄中的脂肪具有一定的降解作用。      

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     

Effects of conjugated linoleic acid supplementation and feeding level on dairy performance,milk fatty acid composition,and body fat changes in mid-lactation goats

The objective of this trial was to study the interaction between the supplementation of lipid-encapsulated conjugated linoleic acid (CLA; 4.5 g of cis-9,trans-11 C18:2 and 4.5 g of trans-10,cis-12 C18:2) and feeding level to test if milk performance or milk fatty acid (FA) profile are affected by the interaction between CLA and feeding level. Twenty-four dairy goats were used in an 8-wk trial with a 3-wk adaptation to the experimental ration that contained corn silage, beet pulp, barley, and a commercial concentrate. During the third week, goats were assigned into blocks of 2 goats according to their dry matter intake (DMI), raw milk yield, and fat yield. Each block was randomly allocated to control (45 g of Ca salt of palm oil/d) or CLA treatment. Within each block, one goat was fed to cover 100% (FL100) of the calculated energy requirements and the other was fed 85% of the DMI of the first goat (FL85). Individual milk production and composition were recorded weekly, and milk FA composition was analyzed in wk 3, 5, and 7. Conjugated linoleic acid supplementation reduced milk fat content and fat yield by 17 and 19%, respectively, independent of the feeding level. It reduced both the secretion of milk FA synthesized de novo, and those taken up from the blood. No interaction between CLA and feeding level was observed on milk secretion of any group of FA. The CLA supplementation had no effect on DMI, milk yield, protein, and lactose yields but it improved calculated net energy for lactation balance. Goats fed the FL100 × CLA diet tended to have the highest DMI and protein yield. The interaction between CLA and feeding level was not significant for any other variables. Compared with the goats fed FL100, those fed FL85 had lower DMI, lower net energy for lactation balance, and lower digestible protein in the intestine balance. The body weight; milk yield; milk fat, protein, and lactose yields; and fat, protein, lactose, and urea contents in milk were not affected by feeding level. In conclusion, reduction in energy spared via fat yield reduction after CLA supplementation was not partitioned toward milk lactose or protein in goats at a low feeding level, possibly because of a simultaneous shortage of energy and amino acids. In goats on the high feeding level, energy spared tended to be partitioned toward milk protein yield, and at the same time to the prevention of excessive lipid mobilization.     

肌内脂肪与背最长肌肉质、脂肪酸组成的关系

研究肌内脂肪（IMF）含量与肉质以及脂肪酸含量和组成比例之间的关系。以北京黑猪背最长肌（n=20）为实验材料,测定肌内脂肪含量、肉质以及脂肪酸含量和组成。结果显示,肌内脂肪含量与滴水损失呈显著正相关（p<0.05）,与蒸煮损失、剪切力、肉色的相关性不显著（p>0.05）。随着肌内脂肪含量升高,除长链多不饱和脂肪酸(C_20:3n6、C_20:4n6)以外的大多数脂肪酸含量增加,相对比例也上升;多不饱和脂肪酸的含量增加,但是相对比例下降;长链多不饱和脂肪酸的含量和相对比例都降低。随着肌内脂肪含量的升高,饱和脂肪酸（SFA）和单不饱和脂肪酸（MUFA）的含量升高,回归方程斜率分别为197.3和248.31,多不饱和脂肪酸（PUFA）增加的幅度不大,回归方程的斜率为11.43。结果提示:肌内脂肪含量较低时（本实验平均值2.86%）,对肉质的影响不显著。随着肌内脂肪含量升高,总脂肪酸含量（TFA）增加,主要归因于SFA和MUFA含量的增加。PUFA的含量相对稳定,受肌内脂肪含量变化的影响较小。      

Effects of dietary taurine on egg production,egg quality and cholesterol levels in Japanese quail

BACKGROUND: Taurine is a semi‐essential amino acid and has many biological properties. The objective of this study was to determine the effect of dietary supplementation with taurine on egg production, egg quality, and cholesterol level in serum and egg yolk of quails. A total of 108 quails aged 6 weeks were randomly allocated to three dietary treatments. Each treatment consisted of four replicates of nine quails. The diets were supplemented with 0, 100, and 500 mg kg^?1 of taurine for 8 weeks. RESULTS: Dietary 500 mg kg^?1 taurine significantly affected egg production rate and feed conversion ratio, but had no significant effects on body weight gain, feed consumption, or egg weight. Dietary taurine had no significant effect on egg quality parameters studied. Serum triglyceride concentration was reduced significantly with supplementation of taurine at 100 and 500 mg kg^?1. Egg yolk cholesterol content was reduced significantly, and the contents of serum taurine and egg yolk taurine were increased significantly with taurine supplementation at 500 mg kg^?1. CONCLUSION: Results of the present study indicated that adding 500 mg kg^?1 taurine reduced yolk cholesterol concentration and increased yolk taurine content without adverse effects on performance and egg quality of laying quails. Copyright © 2010 Society of Chemical Industry     

Effects of dietary fats differing in n-6:n-3 ratio fed to high-yielding dairy cows on fatty acid composition of ovarian compartments, follicular status, and oocyte quality

The objectives were to determine the incorporation of dietary encapsulated fats differing in n-6:n-3 ratio into milk fat, plasma, and various ovarian compartments and to examine the effects on ovarian follicular status, preovulatory follicle characteristics, and oocyte quality. Twenty-four multiparous Israeli Holstein cows, averaging 114 d in milk, were assigned to 1 of 3 treatment groups: 1) control (n = 7), in which cows were fed a lactating cow diet; 2) E-FLAX (n = 8), in which cows were fed a lactating cow diet that consisted of 1 kg/d of encapsulated fat (3.8% of dry matter) containing 40.8% flaxseed oil, providing 242.2 g of C18:3n-3 (low n-6:n-3 ratio); or 3) E-SUN (n = 9), in which cows were fed a lactating cow diet that consisted of 1 kg/d of encapsulated fat (3.8% of dry matter) containing 40.8% sunflower oil, providing 260.0 g of C18:2n-6 (high n-6:n-3 ratio). Ovaries were monitored by ultrasonography for follicular status, and after synchronization, follicles >7 mm were aspirated and evaluated. Ovum pickup was performed (19 sessions for the control and E-FLAX groups and 11 for the E-SUN group), and in vitro maturation and oocyte fertilization were conducted. The E-FLAX treatment increased the proportions of C18:3n-3 (5.8 fold), C20:5n-3, and C22:5n-3 (approximately 4-fold) in milk fat as compared with the other 2 treatments. The proportion of C18:3n-3 fatty acid in plasma increased dramatically with the E-FLAX treatment, from 1.43 and 1.49% in the control and E-SUN groups, respectively, to 7.98% in the E-FLAX group. Consequently, the n-6:n-3 ratio in plasma was reduced from approximately 42 in the control and E-SUN groups to 6.74 in the E-FLAX group. Proportions of C18:3n-3 in follicular fluid and granulosa cells were approximately 5-fold higher in the E-FLAX group than in the other 2 groups. The percentage of C18:2n-6 in cumulus-oocyte complexes of cows in the E-SUN group was 54% higher than that in the E-FLAX group and was 2.4-fold higher than that in the control group; the proportion of C18:3n-3 in the E-FLAX group was 4.73% and was not detected in the other groups. The average numbers of 2- to 5-mm follicles on d 5 and 9 of the cycle were higher in the E-FLAX group than in the E-SUN group, whereas the average numbers of follicles ≥10 mm on d 5, 9, and 13 were higher in the E-SUN group than in the other 2 groups. The estrous cycles of the cows were synchronized and PGF_2α was injected on d 16 to 17 of the cycle. The interval from PGF_2α injection to behavioral estrus was longer in the E-FLAX group than in the E-SUN group, and the beginning of the luteal phase of the subsequent cycle was delayed. Concentrations of estradiol in follicular fluid of the preovulatory follicles were higher in the E-SUN group than in the E-FLAX group. The number of follicles aspirated by ovum pickup was higher in the E-FLAX group than in the control group, and the cleavage rate in the E-FLAX group was higher than in the control group, but not the E-SUN group. In conclusion, dietary n-3 fatty acids influenced the follicular status and increased the cleavage rate of oocytes as compared with those of control cows. These findings could be related to modifications of the fatty acid composition in plasma and ovarian compartments in response to dietary supplementation.