Cumin seed meal as an alternative to wheat bran in commercial laying hen diets

To evaluate the nutritional significance of cumin seed meal (CSM) as a commercial poultry feedstuff on laying hen performance and quality of laid eggs, an experiment was conducted using 144 (48‐week‐old) laying hens receiving diets containing 0, 25 and 50 g CSM kg^?1 with or without polyethylene glycol (PEG 6000) and xylanase enzyme (Grindazym^? GP 15000) for 9 weeks. Body weight on the first and last days of the experiment and daily egg production and egg weight and weekly feed intake during the first, fifth and ninth weeks of the experiment were recorded. Shell weight, shell thickness, Haugh unit and yolk colour were measured during the last week of the experiment. The results showed that inclusion of CSM in laying hen diets had no negative influence on the parameters measured compared with the control diet (P > 0.05), but enhanced egg yolk colour (P < 0.05). PEG increased the daily feed intake of birds receiving CSM diets (P < 0.01) and tended to enhance daily egg production and egg weight, although not significantly. Grindazym decreased shell weight and thickness of laid eggs (P < 0.05) and tended to increase hen body weight, but had no influence on other parameters measured. The results demonstrated that CSM can be substituted for wheat bran in layer diets at 25 or 50 g kg^?1 dietary inclusion level without any adverse effect on hen performance or egg quality, and might enhance egg yolk colour. In view of the low price of CSM, it could be concluded that inclusion of CSM in the diet might be beneficial to the commercial laying hen industry and reduce the overall cost of egg production. Copyright © 2006 Society of Chemical Industry     

The residue levels of narasin in eggs of laying hens fed with unmedicated and medicated feed

Laying hens were fed contaminated feed containing narasin 2.5 mg/kg for 21 days followed by a 7 day withdrawal period, hens in the control group were fed unmedicated feed. Eggs were collected during trial days 0, 3, 7, 14, 21 and after the withdrawal period of 7 days. The concentration of narasin in yolks and egg whites was analyzed by a liquid chromatography-mass spectrometry method. Narasin was found to accumulate in yolks, where the narasin concentration increased during the treatment. The concentration of narasin varied from 5.9 to 13.8 microg/kg (mean 10.6 microg/kg) in yolks after 21 day feeding periods. The concentrations of narasin ranged from < 0.9 to 1.4 microg/kg after the withdrawal period. Narasin residues were not found in egg whites of the laying hens fed contaminated feed nor in either yolks or egg whites of the laying hens fed unmedicated feed. The effect of cooking was also tested on the amount of narasin residues in eggs. Cooking for 10 min did not significantly influence the narasin residues in eggs. Traces of lasalocid were also found in the yolks. The traces of lasalocid are attributable to an accidental contamination of the feed during its manufacture.     

Toxicity of rapeseed meal and its use as a protein supplement in the diet of two hybrid strains of caged laying hens

An experiment is described in which extracted Algerian rapeseed meal was included at levels of 4, 8, 12, 16 and 20% in the diet of two hybrid strains of caged laying hens. The rapeseed meal was thyrotoxic and this effect, when assessed by thyroid weight per kg of body weight, was more marked for the light-weight hybrid than for the medium-weight hybrid birds. The light-weight hybrids exhibited a high mortality when fed rapeseed meal at a level of 8 % or above in the diet but inclusion of rapeseed meal did not cause increased mortality in the medium-weight hybrids. The medium-weight hybrids gave satisfactory egg production when fed up to 16% of dietary rapeseed meal; food conversion efficiency was best with 8% of dietary rapeseed meal, and metabolisable energy conversion (Meal/kg eggs) and the efficiency of utilisation of protein were, satisfactory at all levels of rapeseed meal inclusion. The rapeseed meal used had a standard metabolisable energy content of 1820 kcal/kg at a dry matter content of 89 %.     

The nutritional value of dried skim milk in the diet of laying hens

An experiment is reported in which dried skim milk was used at levels of 0, 40, 80, 120 and 160 g kg^?1 of diet to replace mainly soyabean meal in the diets of two breeds of laying hens. AME and AME_n were significantly adversely affected by the two highest levels of added dried skim milk. Food conversion efficiency and bodyweight were unaffected by the added dried skim milk. Although overall food intake and egg number were not statistically significantly affected by dietary treatment there was a tendency towards a decline in both variables at the highest level of dried skim milk inclusion. The response of mean egg weight to increasing levels of dried skim milk was positively linear. Total egg weight was significantly affected by dietary treatment, the response being quadratic.     

Omega‐3 Fatty Acid Profile of Eggs from Laying Hens Fed Diets Supplemented with Chia,Fish Oil,and Flaxseed

The aim of this study was to investigate the effect of diets supplemented with fish oil, flaxseed, and chia seed on the omega‐3 fatty acid composition and sensory properties of hens’ eggs. No significant difference in yolk fat content was found between treatments. The fatty acid composition of egg yolk was significantly affected by the dietary treatments. Inclusion of chia at 300 g/kg into the diet produced eggs with the highest concentration of omega‐3 fatty acid. Eicosapentaenoic acid and docosahexaenoic acid were only detected in eggs from laying hens fed the diet supplemented with fish oil. Diet had a significant effect on color, flavor and overall acceptability of eggs. Types and levels of omega‐3 fatty acids in feed influence the level of yolk omega‐3 fatty acids in egg yolk. Inclusion of chia into the hens’ diet significantly increased the concentration of yolk omega‐3 fatty acid without significant change in sensory properties.     

Fatty acid profile and cholesterol content of egg yolk from chickens fed diets supplemented with purslane (Portulaca oleracea L.)

BACKGROUND: The aim of the present study was to evaluate the effects of purslane on egg production, egg weight, feed efficiency, yolk fatty acid composition, and egg cholesterol content in laying hens. MATERIAL AND METHODS: Sixty 80‐week‐old layers were allocated randomly to receive diets supplemented with 0 (control), 10 g kg^?1 or 20 g kg^?1 dried purslane for 84 days. Egg weights and egg production in the groups were recorded daily, whereas feed intake was measured weekly. RESULTS: Diet supplemented with 20 g kg^?1 purslane significantly decreased body weight of the chickens compared to the control. Inclusion of purslane at the level of 10 g kg^?1 or 20 g kg^?1 into the diet significantly (P < 0.05) improved egg weight compared to the control. Chickens fed the diet including 20 g kg^?1 purslane had a significantly (P < 0.05) higher egg production and improved feed efficiency compared to the control. Cholesterol content of eggs from the hens fed 0, 10 or 20 g kg^?1 did not differ and was 10.45, 9.51 or 9.51 mg g^?1 dried egg yolk, respectively. Inclusion of purslane at the level of 20 g kg^?1 into the diet significantly (P < 0.05) increased ω‐3 fatty acids such as C18:3(ω‐3) and C22:6(ω‐3). The ratio of ω‐6 to ω‐3 also was significantly (P < 0.05) lower in the eggs from chickens fed 10 g kg^?1 or 20 g kg^?1 purslane supplemented diets compared to the control. CONCLUSION: This study showed that adding dried purslane to the diet of laying hens significantly increased egg production and egg weights although there was no reduction in the egg cholesterol concentration. This study also showed that inclusion of purslane into diet enriched eggs with ω‐3 fatty acids and decreased the ratio of ω‐6/ω‐3 in the yolk. Copyright © 2010 Society of Chemical Industry     

The Influence of Feeding Yellow-, Green- and Brown-Seeded Peas on Production Performance of Laying Hens

Two experiments were conducted to evaluate the feeding value of yellow-, green- and brown-seeded peas as protein and energy supplements in laying hen diets. In experiment 1, all three types of peas were included in laying hen diets at 0, 200, 400 and 600 g kg^-1 replacing wheat and soya bean meal. Layers fed diets containing peas at 200 g kg^-1 produced more (P⩽0·05) eggs, had higher (P⩽0·05) egg mass output and better (P⩽0·01) feed conversion than those fed the wheat soya bean meal control diet. With 400 g peas kg^-1 in diets, egg production, egg mass and feed conversion were similar (P⩾0·05) to the control diet. Total replacement of soya bean meal with peas (600 g peas kg^-1 in diets) reduced (P⩽0·01) egg production, egg mass and feed conversion. A progressive (P⩽0·01) improvement in yolk colour as the level of peas in the diet increased was observed. Shell quality decreased (P⩽0·05) with increasing levels of yellow or brown peas in the diets, however, it seemed not to be affected by green peas. Daily feed intake, egg weight and mortality rates were not affected by dietary treatments. The influence of feeding diets containing yellow or brown peas supplemented with varied levels of methionine on production performance of laying hens was investigated in experiment 2. The dietary treatments consisted of a 400 g kg^-1 yellow or brown pea diet supplemented with three levels of methionine to 100, 115 and 130% of the NRC requirements. Methionine supplementation to either 15 or 30% above NRC requirement for laying hens had no significant (P⩾0·05) effect on all production parameters. It can be concluded that the inclusion of yellow, green or brown peas into laying hen diets up to 400 g kg^-1 does not affect production performance. The NRC recommendation of methionine requirement for laying hens is adequate to support maximum egg production for diets containing moderate quantities of peas. © 1997 SCI.     

Aflatoxin B1 residues in eggs of laying hens fed a diet containing different levels of the mycotoxin.

The present study was carried out to evaluate the excretion of aflatoxin B1 residues in eggs of young laying hens fed aflatoxin B1-contaminated rations for 8 weeks. To this end, 96 twenty-week-old hens were randomly distributed into four experimental groups (24 birds per group) and given rations containing either 0 (controls), 100 micrograms, 300 micrograms or 500 micrograms aflatoxin B1/kg feed. Egg aflatoxin B1 residues were determined by thin layer chromatography; two samples per treatment per week were used for analysis. Egg production and average egg weights were not affected (p < 0.05) in the groups receiving aflatoxin B1-contaminated rations. Residues of aflatoxin B1 were detected only in the eggs of hens given 500 micrograms/kg feed, at levels that ranged from 0.05 to 0.16 microgram/kg (average: 0.10 microgram/kg). The results indicate that the feed to eggs aflatoxin B1 transmission ratio was approximately 5000:1, emphasizing the importance of controlling aflatoxin levels in rations for laying hens.     

棉粕致鸡蛋变色机制研究

目的探讨棉籽粕饲料诱导鸡蛋变色的机制。方法在蛋鸡饲料中分别添加醋酸棉酚和环丙烯脂肪酸,测定蛋清蛋黄色泽变化,蛋黄膜的超微结构变化,冷藏后蛋清蛋黄的PH,钙、铁离子含量等相关指标的变化。结果棉籽粕中的环丙烯脂肪酸是引起蛋清冷藏后呈桃红色的主要原因,环丙烯脂肪酸引起蛋黄膜通透性增加,冷藏过程中蛋黄中的钙、铁元素外流到蛋清中与副卵蛋白结合呈桃红色。结论棉籽粕诱导的鸡蛋变色是化学、物理、生物学变化的综合现象。     

Combined effect of antibiotic and competitive exclusion treatment on Salmonella enteritidis fecal shedding in molted laying hens

Salmonella Enteritidis is an important pathogen for the layer industry, primarily because of its ability to infect hens and ultimately contaminate egg contents. Studies have shown that stress situations, such as flock recycling (induced molting), can increase Salmonella Enteritidis problems in the flock. The present study examined the effect of antibiotic treatment and competitive exclusion (CE) on Salmonella Enteritidis shedding in the period following molt and 14-day feed withdrawal. In two separate trials, 48 birds after molt and feed withdrawal were divided into one group that was treated for 10 days with enrofloxacin in water followed by administration of CE culture and a group that was left untreated. Salmonella Enteritidis shedding was significantly reduced in the antibiotic-CE group. The Salmonella Enteritidis shedding rate was 33 and 25% in untreated birds versus 4 and 0% in the enrofloxacin-CE group on the two test days. These results indicate that treatment of Salmonella Enteritidis-positive laying hens after molting with enrofloxacin and CE culture can substantially reduce Salmonella Enteritidis problems due to molting and would be a possible alternative to diverting eggs for pasteurization or slaughtering the infected flock. Possible development of bacterial resistance in conjunction with antibiotic use is also discussed.     

Enrichment of eggs in n-3 polyunsaturated fatty acids by feeding hens with different amount of linseed oil in diet

The production of n-3 polyunsaturated fatty acid enriched eggs by addition of linseed oil to the laying hens' diet has been evaluated in terms of production parameters and n-6/n-3 ratio. A total of 150 18weeks old Lohmann Brown laying hens were housed in cages and fed with basal diet and four experimental diets containing 1%, 2%, 3% or 4% of linseed oil added to the basal diet. The effect of the altered level of linseed oil on hens laying performance, fatty acid content and composition and cholesterol content in egg yolk has been evaluated during 13weeks of experiment. Egg weight, yolk fat content, yolk weight, yolk percentage and shape index were not influenced by dietary treatment. The ratio between n-6 and n-3 polyunsaturated fatty acids in eggs decreased in first 5weeks and then remained stable until the end of the experiment for all experimental groups. Different contents of linseed oil in feed highly influenced the n-6/n-3 ratio (P<0.0001). Addition of linseed oil did not influence the cholesterol content in yolks (P=0.5200) while the only factor affecting the cholesterol content was the hens age (P<0.0001).     

n-3脂肪酸鸡蛋营养价值分析

n-3类脂肪酸健康功效明确,其中EPA和DHA对降低心血管疾病风险等方面有较强作用,但人群摄入量往往不足.研究表明,通过对母鸡饲料进行n-3脂肪酸强化能有效地增加蛋黄内EPA和DHA的含量,其中DHA强化鸡蛋比未强化鸡蛋含量高2.4～10倍.每人每天食用1～2个n-3脂肪酸鸡蛋可使得机体每日摄入的EPA和DHA达到膳食推荐量.而由于n-3脂肪酸的引入,相应的安全性评估也应加强,包括需从n-3脂肪酸的摄入量、n-3脂肪酸鸡蛋里的深海鱼污染物和胆固醇含量等几个方面进行评价.     

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     

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     

Deposition of carotenoids in egg yolk by short‐term supplement of coloured carrot (Daucus carota) varieties as forage material for egg‐laying hens

BACKGROUND: Supplying egg‐laying hens with different forage materials may influence egg production and quality. The aim of this study was to examine the short‐term effects of standard feed plus 70 g day^?1 per hen of three coloured carrot varieties (orange, yellow and purple) as forage material in comparison with a standard feed control on egg production, egg yolk colour and deposition of carotenoids in the yolk. RESULTS: Carrot supplementation reduced feed intakes significantly, but not on a dry matter basis. Orange carrot treatment significantly reduced egg mass production, whereas yellow and purple carrot treatments did not differ from the control. Egg and yolk weights of all carrot‐supplemented treatments were significantly lower than those of the control, but yolk percentages were similar. Yolk redness increased significantly in the order control < yellow < orange < purple. A similar trend was seen for yolk yellowness, but yellow and orange carrots reached the same level. Yolk colour and carotenoid contents correlated positively and significantly. In particular, purple carrot treatment increased the yolk content of lutein (>1.5‐fold) and β‐carotene (>100‐fold) compared with the control. CONCLUSION: Supplementing the feed of egg‐laying hens with coloured carrots efficiently increased yolk colour parameters and carotenoid contents, which gives opportunities for improved nutritional value of eggs from forage material‐supplemented hens. Copyright © 2010 Society of Chemical Industry     

The nutritional value of cassava root meal in laying hen diets

Two hundred and eighty-eight laying hens (144 Hisex white, 144 Hisex brown) were randomly allocated to one of twelve dietary treatments and fed ad libitum for ten 28 day periods. The diets, fed either as mash or pelleted, were a control diet and five other diets with increasing levels of added cassava root meal (100, 200, 300, 400, 500 g kg^?1 diet). At the end of the experiment, four Hisex white birds from each treatment were taken for the measurement of water intake. The AME content of the diets was measured by the total collection method. The inclusion of high levels of cassava root meal had no detrimental effect on egg production or food intake. However, as the level of cassava increased, there was a tendency towards a decrease in food consumption in the meal-fed birds. Water consumption was significantly greater in the birds given pelleted feed than in those given mash. Also, at the higher levels of cassava inclusion in the meal-fed birds, water consumption was greater. The AME content of the cassava root meal was 14.1 MJ kg^?1 dry matter.     

Reduction of aflatoxins by Korean soybean paste and its effect on cytotoxicity and reproductive toxicity--Part 3. Inhibitory effects of Korean soybean paste (doen-jang) on aflatoxin toxicity in laying hens and aflatoxin accumulation in their eggs

This study was conducted to determine the effects of Korean soybean paste (doen-jang [dwen-jahng]) (at concentrations of 0.5, 1, and 5%) on the toxicity of 500 ppb of aflatoxin in the diets of 60 laying hens (Isa Brown) divided into five groups and treated from week 15 to week 67. The aflatoxin-treated hens exhibited many deleterious effects, including reduced body weight; increased relative organ weights; decreased egg production; aflatoxin accumulation in eggs; decreased serum calcium, phosphorus, and alanino amonotransferase (ALT) levels; increased serum gammaglutamil transferase and lactic dehydrogenase levels; and, most significantly, severely altered cell foci and sinusoid dilatation in the liver, relative to control hens. The feeding of 1% soybean paste to hens reduced the adverse effects of aflatoxin on body weight, relative organ weights, egg production, and aflatoxin accumulation in eggs and improved serum calcium and ALT levels and the histopathological lesions of the liver. The feeding of 5% soybean paste to hens resulted in higher levels of the same types of improvements, especially with regard to the histopathological findings for the liver. On the basis of these results, it was suggested that a diet including 5% (and in some cases only 1%) Korean soybean paste protected laying hens and their eggs from the major deleterious effects of 500 microg of aflatoxin per kg of diet and from aflatoxin accumulation. These results indicate that dietary supplementation with Korean soybean paste reduces aflatoxin toxicity in laying hens that ultimately produce human foods such as eggs and poultry.     

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.     

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.     

An automated HPLC determination of meticlorpindol in eggs with UV absorbance detection, using on-line dialysis and pre-concentration as sample clean-up; occurrence in and carry over to eggs

A fully automated HPLC determination of the coccidiostat meticlorpindol in whole egg, egg white and yolk is described. The sample homogenate is dialysed on-line against water. The dialysate is concentrated on-line on a short reversed-phase (RP) column. The contents of this column are transferred to the reversed-phase analytical column by means of the mobile phase. Meticlorpindol is detected using an absorbance detector at 270 nm. Linear calibration graphs are obtained in the range 40-900 ng/g in whole egg and egg white (detection limit 10 ng/g) and 80-1800 ng/g in yolk (detection limit 20 ng/g). Out of 111 commercially obtained egg samples 12 contained meticlorpindol with levels varying from 10 to 433 ng/g. A group of laying hens, kept in cages, received 10 mg/kg of Lerbek (meticlorpindol and methylbenzoquate; Dow Chemical) in the feed for 10 days. Meticlorpindol residues in the eggs rose to a level of 622 ng/g. Meticlorpindol was found in the eggs until 6 days after withdrawal of the medicated feed. Another group received 110 mg/kg in the feed. Meticlorpindol residues rose to levels of 4480 ng/g in the eggs, 5880 ng/g in the egg white and 2660 ng/g in the yolk. Meticlorpindol was found in the eggs and the egg white until 14 days and in the yolk until 8 days after withdrawal of the medicated feed.