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.     

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     

Chorioallantoic membranes indicate avian exposure and biomarker responses to environmental contaminants: a laboratory study with White Leghorn chickens (Gallus domesticus)

PCB and endosulfan concentrations in the chorioallantoic membrane (CAM) of white leghorn chickens (Gallus domesticus) were evaluated as indicators of hepatic cytochrome P450 isozyme activity in hens and chicks as well as toxicant concentrations in eggs and hens. Sixteen hens were randomly divided into four groups of four and dosed with a mixture of PCB105 (2,3,3',4,4'-pentachlorobiphenyl), PCB156(2,3,3',4,4',5-hexachlorobiphenyl), PCB189 (2,3,3',4,4',5,5'-heptachlorobiphenyl), and technical grade endosulfan (3:1 ratio of alpha and beta isomers) at three different dose groups. The first 10 fertile eggs laid by each hen were collected, the even-numbered eggs incubated until hatched, and the odd numbered eggs were analyzed for test chemicals. Strong (r2), significantly positive (p value) relationships were found between total PCB mass (ng) in CAMs and both total PCB concentrations (ng/g wet wt) in adults (r2 = 0.91, p = 0.0001) and eggs (r2 = 0.87, p = 0.0001). The relationship between total PCB mass in CAMs and hepatic cytochrome p450 isozyme activity in chicks (r2 = 0.49, p = 0.0001) and hens (r2 = 0.45, p = 0.014) was also significant but not as strong. This study shows that CAMs can be used to estimate avian exposure to PCBs and resultant biological response.     

Oxidative Stability and Sensory Quality of Stored Eggs From Hens Fed 1.5% Menhaden Oil

Effects of refrigerated storage on thiobarbituric acid (TBA) values and sensory scores of shell eggs from hens fed 1.5% menhaden oil (MO) and a no-added fat control diet were investigated. Eggs were collected weekly (0, 1, 2, 3, 4) for each of three replicates/diet and all weeks were analyzed within 24 hr of 0 week. The flavor of scrambled samples from stored shell eggs (wk 0, 2, 4) was determined by scoring difference scale administered to two consumer panels (n = 40/panel). Flavor scores for eggs from all treatments were not different. TBA values were greater (P < 0.05) in MO eggs at week 0 but did not increase during storage. Storage stability of shell eggs from hens fed 1.5% dietary menhaden oil is comparable to that from hens fed a no-added fat diet.     

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.     

Dietary mycotoxins binders: a strategy to reduce aflatoxin m1 residues and improve milk quality of lactating Beetal goats

Aflatoxin M1 (AFM1) is a metabolite of aflatoxin B1 (AFB1) and secreted in milk of animals that are kept on a moldy diet. AFB1 is produced by several toxigenic species of fungi. In this study, the comparative efficacy of two mycotoxin binders was evaluated in terms of reducing excretion of AFM1, total viable bacterial count and somatic cell count in milk obtained from goats fed with AFB1 contaminated diet. A total of 32 lactating Beetal goats were reared and divided into 4 equal groups: Animals of group A were kept as control, while those in groups B, C, and D were individually fed with AFB1 at 40 µg alone, 40 µg AFB1 along with mycotoxin binder Toxfin^® at 3 g kg^?1 of cotton seed cake, and 40 µg AFB1 along with mycotoxin binder Elitox^® at a dose rate of 1 g kg^?1 of cotton seed cake, respectively. Toxfin^® significantly decreased the excretion of AFM1 in goats’ milk by 49.57 % while Elitox^® non-significantly reduced the excretion of AFM1 in goats’ milk by 19.49 %. Total viable bacterial count in milk samples of group C and D, and somatic cell count in milk samples of group C did not reduce significantly. However, somatic cell count in milk samples of group D reduced significantly. We conclude that the addition of Toxfin^® in the moldy diet significantly reduce the excretion of AFM1 in animals’ milk and minimize the risk of mycotoxin toxicity to public health.     

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     

Long-term administration of low doses of mycotoxins to poultry. 1. Residues of aflatoxin B1 and its metabolites in broilers and laying hens

A study was performed to determine aflatoxin residues in tissues and organs of male broilers and hens that had been fed a diet contaminated with 50 micrograms/kg aflatoxin B1 (AFB1). Residue levels of AFB1, aflatoxicol (Ro), aflatoxin M1 (AFM1) and aflatoxin B2a (AFB2a) were determined by an HPLC method and, with the exception of AFB2a, were detected in the liver, kidney and thigh of both male broilers and hens. The highest levels found were for Ro in liver (1.10 and 0.60 micrograms/kg for male broilers and hens, respectively). On the other hand no detectable amounts of aflatoxins were found in any tissue after withdrawal periods of 14 and 33 days for male broilers and laying hens respectively.     

Long term administration of low doses of mycotoxins in poultry. 2. Residues of ochratoxin A and aflatoxins in broilers and laying hens after combined administration of ochratoxin A and aflatoxin B1

The effects of combined administration of ochratoxin A (OA) and aflatoxin B1 (AFB1) on the occurrence and the levels of residues of mycotoxins in poultry have been investigated. Male broilers and laying hens were fed from 14 days old with standard diets contaminated with 50 micrograms/kg OA and 50 micrograms/kg AFB1. Two groups of broilers and hens were withdrawn from contaminated feed at 37 and 88 days, respectively. At the time of sacrifice no significant lesions were found. Residues were compared with those found after administration of either toxin alone in former trials. Combined treatment resulted in higher content of OA in broiler livers (40 versus 5.0 micrograms/kg) and, to a lesser extent, in kidneys and skin, and of AFB1 in broiler liver and kidney (0.15 versus 0.02 microgram/kg and 0.40 versus 0.05 microgram/kg respectively). Laying hens showed smaller differences (0.20 versus 0.10 microgram/kg in liver and 0.32 versus 0.08 in kidneys). Withdrawal from treatment led to the almost complete disappearance of OA residues in broilers and in hens. These results show a synergistic effect of OA and AFB1, particularly in broilers.     

HPLC determination of the total content of aflatoxins in naturally contaminated eggs in free and conjugate forms

A study was undertaken to evaluate the total aflatoxin content in naturally contaminated eggs. Two pools of eggs from laying hens were collected after 2 and 7 days of treatment with aflatoxin B1 (AFB1). An HPLC method has been developed for the determination of AFB1, aflatoxin M1 (AFM1), aflatoxin B2a (AFB2a) and aflatoxicol (Ro) both in free form and after release from water-soluble conjugates. The bound form was cleaned up after acid hydrolysis of the aqueous phase. Eggs collected after 2 days of treatment revealed residues of AFB1, AFB2a and Ro in the organic phase, but none in the aqueous portion. After 7 days of treatment both AFB1 and its hydroxy derivative were found in the organic phase but the aqueous portion showed only hydroxylated metabolites accounting for 35% of the total aflatoxin content.     

Lipid oxidation of stored eggs enriched with very long chain n−3 fatty acids,as affected by dietary olive leaves (Olea europea L.) or α-tocopheryl acetate supplementation

The antioxidant potential of dietary olive leaves or α-tocopheryl acetate supplementation on lipid oxidation of refrigerated stored hen eggs enriched with very long-chain n−3 fatty acids, was investigated. Ninety-six brown Lohmann laying hens, were equally assigned into three groups. Hens within the control group were given a typical diet containing 3% fish oil, whereas other groups were given the same diet further supplemented with 10 g ground olive leaves/kg feed or 200 mg α-tocopheryl acetate/kg feed. Results showed that α-tocopheryl acetate or olive leaves supplementation had no significant effect on the fatty acid composition and malondialdehyde (MDA) levels of fresh eggs but reduced their lipid hydroperoxide levels compared to controls. Storage for 60 d decreased the proportions of polyunsaturated fatty acids (PUFAs) but increased those of monounsaturated fatty acids (MUFAs) in eggs from the control group, while had no effect on the fatty acid composition of the eggs from the other two groups, which showed decreased levels of lipid hydroperoxides and MDA. Therefore, the very long chain n−3 PUFAs in eggs were protected from undergoing deterioration partly by olive leaves supplementation and totally by α-tocopheryl acetate supplementation. In addition, incorporating tocopherols into eggs might also provide a source of tocopherols for the human diet.     

恩诺沙星、氟苯尼考和泰万菌素在鸡蛋中残留消除规律研究

目的 评估恩诺沙星、氟苯尼考和泰万菌素在鸡蛋中的残留消除规律。方法 将80羽高产海兰褐蛋鸡随机等分成4组, 对照组饲喂基础日粮, 恩诺沙星组、氟苯尼考组和泰万菌素组分别经混饲给予相应药物, 每日1次, 连续给药5 d, 停药19 d, 检测各枚鸡蛋中相应药物及其主要代谢产物的残留量。结果 恩诺沙星及其主要代谢产物环丙沙星与氟苯尼考及其主要代谢产物氟苯尼考胺可迅速残留于鸡蛋中, 残留物分别以恩诺沙星原型和氟苯尼考原型为主, 且其残留蓄积期都超过19 d。泰万菌素及其主要代谢产物3-乙酰胺基泰万菌素在鸡蛋中的残留总量低于最大允许残留限量, 且平均残留蓄积期为7 d, 3-乙酰胺基泰万菌素占总残留量的50%以上。结论 恩诺沙星和氟苯尼考在海兰褐品系鸡蛋中残留消除周期超过19 d, 在对后备蛋鸡、肉蛋兼用鸡给药时需严格控制用法用量。在适用情况下, 可优先选择平均残留消除周期相对较短的泰万菌素。     

日粮添加苜蓿草粉对固始鸡血清生化指标和免疫器官发育的影响

研究不同苜蓿草粉添加水平对固始鸡血清生化指标和免疫器官发育的影响,选取同批孵化的健康固始鸡慢羽纯系公母混雏1 152只,随机分为6组,每组设4个重复,每个重复48只,公母各半,分别饲喂添加0%、5%、10%、15%、20%、25%苜蓿草粉的日粮至8周龄。结果表明:在4周龄和8周龄时日粮苜蓿草粉添加水平对大部分血清生化指标没有显著影响(P0.05)。除在4周龄时胸腺指数试验Ⅱ组与对照组间差异显著、在6周龄时法氏囊指数试验Ⅱ组与对照组间差异显著、在8周龄时脾脏指数试验Ⅱ组与对照组间差异显著(P0.05)外,其余各周龄时试验组与对照组间免疫器官指数差异均不显著(P0.05)。固始鸡能够从苜蓿草粉含量较高的饲粮中摄取充足的营养物质,维持自身的营养和能量需要,在为固始鸡配制日粮时可以添加较高水平的苜蓿草粉。     

In vitro model to assess the adsorption of oral veterinary drugs to mycotoxin binders in a feed- and aflatoxin B1-containing buffered matrix

Mycotoxin binders are feed additives which are mixed in the feed to adsorb mycotoxins and thereby reducing their toxic effects on animals. Interactions with orally administered veterinary medicinal products, such as antimicrobials or coccidiostats, have been reported previously. This paper describes an in vitro model to screen the interaction between mycotoxin binders and veterinary drugs with respect to the non-specific binding of drugs. It is designed as a static setup using a single concentration of drug and binder in a feed-containing or a feed-plus-mycotoxin-containing matrix, buffered at different pH values. The model was applied to two frequently used antimicrobials in veterinary medicine, doxycycline (DOX) and tylosin (TYL), one major mycotoxin, aflatoxin B1 (AFB1), and four mycotoxin binders. Proportions of feed, DOX or TYL, AFB1, and binder are equivalent to the in vivo situation for broiler chickens, while pH and volume of the buffer are representative of the gastrointestinal tract of chickens. A substantial binding of DOX (~ 88%) and TYL (~ 66%) to the feed-matrix was observed. For the mycotoxin binders, similar results were obtained for DOX and TYL; more specifically up to an inclusion rate of 20 g binder/kg feed, no significant binding was demonstrated, determined as the free concentration of DOX and TYL. A single exception was noticed for TYL and one specific bentonite-based mycotoxin binder, for which no significant interaction could be demonstrated up to 10 g binder/kg but there was an effect at 20 g/kg. In all cases, there was no competition between the tested drugs DOX or TYL and the mycotoxin AFB1 for binding to the bentonite-based mycotoxin binder.     

氟苯尼考在鸡蛋和蛋鸡组织中的残留规律及预测模型建立

氟苯尼考是一种被广泛应用于动物养殖过程中的抗生素药物，可能残留于畜产品中，被人类长期食用会对机体造成耐药性、免疫抑制等不良影响。本实验旨在探讨蛋鸡摄入不同剂量氟苯尼考后，鸡蛋及各组织中氟苯尼考及其代谢产物氟苯尼考胺的清除规律，建立残留预测数学模型。本实验选取处于产蛋高峰期的罗曼粉壳蛋鸡250 只（350 日龄、体质量（1.97±0.07）kg），随机分为5 组，每组50 只，分别给予氟苯尼考0（对照）、30、60、120、240 mg/（kg mb·d），连续给药5 d。采用液相色谱-串联质谱法测定不同休药时间点蛋黄、蛋清、卵黄、肌肉、肝脏中氟苯尼考及其代谢产物氟苯尼考胺的残留含量。结果表明：休药1～3 d时，240 mg/（kg mb·d）剂量组蛋鸡产蛋率与其他处理组相比显著降低（P＜0.05），休药4 d后恢复至对照组水平；氟苯尼考及其代谢产物氟苯尼考胺在产蛋鸡组织中残留含量分布：蛋黄＞卵黄＞蛋清＞肝脏＞肌肉；不同组织残留氟苯尼考及氟苯尼消除所需休药时间：肝脏＜肌肉＜蛋清＜蛋黄＜卵黄；氟苯尼考给药剂量和休药时间对残留含量影响高度显著（P＜0.001），且给药剂量与休药时间互作效应高度显著（P＜0.001）。休药时间、给药剂量和残留含量之间呈现二元二次回归关系（P＜0.001）。为达到《中国兽药典（2015年版）》所规定的氟苯尼考给药剂量范围（40～60 mg/（kg mb·d）），肌肉等组织需休药1 d、蛋清蛋黄需休药13 d、卵黄需休药21 d。     

Fatty acid profile and sensory characteristics of table eggs from laying hens fed hempseed and hempseed oil

Hempseed (HS) is rich in omega-3 polyunsaturated fatty acids, with approximately 17% of total fatty acids as alpha-linolenic acid. As such, HS and its oil may be used in hen diet formulations to produce eggs enriched in essential fatty acids. Because omega-3 eggs have the potential for unpleasant aromas and flavors, the current study was designed to assess the fatty acid profile and sensory attributes of eggs procured from hens consuming diets containing hempseed oil (HO) or HS. A total of 48 individually caged White Bovan hens received 1 of 6 diets containing 4%, 8%, 12% HO, 10%, 20% HS or 0% hemp (w/w) for 12 wk. Total omega-3 polyunsaturated fatty acid content was highest in the 12% HO group (15.3 mg/g of yolk) compared to the control (2.4 mg/g of yolk). Trained panellists (n= 8) found no significant differences (P≥ 0.05) in aroma or flavor between cooked eggs from different dietary treatments, with the exception of sweet flavor. The 4% HO group yielded the least sweet eggs compared to the 20% HS group, which was highest. For yolk color, L*, a*, and b* values (Mean ± SEM) for control eggs were 61.2 ± 0.10, 1.1 ± 0.05, and 43.0 ± 0.22, respectively. Addition of hemp led to significant (P < 0.001) reductions in L*, and significant increases in a* and b*, with the largest changes observed in the 20% HS treatment (L*= 58.7 ± 0.10; a*= 5.8 ± 0.05; b*= 60.5 ± 0.22). The results show that hemp use in hen diets leads to increased omega-3 polyunsaturated fatty acid content and color intensity of egg yolks, but does not have adverse effects on the sensory profiles of the cooked eggs. PRACTICAL APPLICATION: This study provides evidence that HS and hempseed oil (HO) can safely be utilized as feed ingredients for laying hens to produce table eggs that are enriched in essential fatty acids. Additionally, the eggs procured from these hens had similar aroma and flavor compared to eggs from hens not fed any hemp. The greater the dietary hemp inclusion, the more pigmented the resulting yolks became in terms of darkness, redness, and yellowness.     

大米蛋白肽对固始鸡生产性能、蛋白沉积及相关激素分泌的影响

为了研究大米蛋白肽对固始鸡生产性能、蛋白沉积和相关激素分泌的影响,选择发育正常、体重相近的1日龄固始鸡300羽,随机分为5组,每组下设3个重复。对照组(0组)饲喂基础日粮,试验组(1~4组)在基础日粮中分别用0.5%、1%、1.5%、2%的大米蛋白肽代替豆粕,试验结束时测定生产性能、蛋白沉积和相关激素含量。结果显示,添加1.5%~2%的大米蛋白肽能明显提高固始鸡的生产性能和体内蛋白的沉积(P0.05),显著增加固始鸡血清中生长激素(GH)、三碘甲腺原氨酸(T3)和类胰岛素生长因子-Ⅰ(IGF-Ⅰ)的含量(P0.05),同时也使三碘甲腺原氨酸(T3)/四碘甲腺原氨酸(T4)的值明显提高(P0.05)。表明大米蛋白肽能提高固始鸡的生产性能和蛋白沉积,改善鸡的胴体品质。     

GROWTH, SURVIVAL AND HEAT RESISTANCE OF SALMONELLA TYPHIMURIUM AND ESCHERICHIA COLI IN REGULAR AND OMEGA-3 HENS EGG PRODUCTS

Omega‐3 enriched eggs are currently produced by hens fed a flax diet. Since omega‐3 polyunsaturatedfatty acids are prone to oxidation, the addition of vitamin E is supplemented into the hen's diet as an antioxidant. Typically these eggs contain about 2 and 4 times more omega‐3 fatty acids and vitamin E, respectively compared to regular eggs. Since table eggs have a long history of association with foodborne salmonellosis, it was of interest to compare the growth and/or survival of several bacterial pathogens in omega‐3 and regular eggs. In this respect nalidixic‐resistant Escherichia coli and Salmonella Typhimurium were inoculated into regular and omega‐3 hen's egg products (whole eggs, albumen, yolk) and incubated at 22, 8 and ?20C. Time‐course studies indicated that by 72 h both Salmonella and E. coli levels increased by 7 logs at 22C in both types of whole egg. At 8C population levels for these bacteria both increased by approximately 3 logs at 6 weeks. In regular and omega‐3 yolks, salmonellae maintained at 22 and 8C for 48 h and 6 weeks increased by approximately 6 and 1.5 logs, respectively. E. coli levels were higher in egg yolk compared to Salmonella at both temperatures. Regardless of the yolk source, however, no significant (P > 0.05) differences in population levels were observed. Survival patterns of E. coli at ?20C were not significantly (P > 0.05) different between whole egg sources. This trend was also observed in the yolks. For Salmonella no significant (P > 0.05) differences in survival were observed between yolk preparations maintained at ?20C. Increasing the level of α‐tocopherol from c. 63 to 240 ppm in regular egg yolk, resulted in no significant (P > 0.05) differences in the growth of Salmonella at 22C. In addition, when the bacterium was heated in regular egg yolk amended with vitamin E at 56.5C, no significant (P > 0.05) difference was observed in resistance regardless of α‐tocopherol (55‐713 ppm) or total tochopherol (92–1238 ppm) level.     

Fatty acids,health indices and sensory properties of Ricotta cheese from sheep fed three different diets

The study evaluates the healthy fatty acid profile and sensorial characteristics of Ricotta obtained from ewes fed three different diets: diet enriched with linseed (L), un‐supplemented diet (F) and pasture (P). Omega‐3 fatty acid (n‐3 FA) levels in Ricotta from grazing sheep and from animals that received the supplemented diet were notably higher than those that received un‐supplemented feed. The L‐ and P‐groups had lower levels of saturated fatty acids (SFAs), higher levels of conjugated linoleic acid (CLA) and more favourable health indices. Sensorial tests showed that among the diet groups, the Ricotta obtained from the supplementation group scored the highest with respect to greasiness, spreadability and acceptability.     

Effect of grass–clover forage and whole‐wheat feeding on the sensory quality of eggs

BACKGROUND: A sensory panel evaluated the sensory profile of eggs from hens from three experimental systems: (1) an indoor system × normal layer diet (InL), (2) a grass–clover forage system × normal layer diet (GrL), and (3) a grass–clover forage system × whole wheat and oyster shells (GrW). RESULTS: The taste of the albumen was significantly more ‘watery’ and the yolks a darker yellow/orange in the eggs from the GrL and GrW groups. The yolk was darkest from the GrW group. The yolks from the InL and GrW groups had a significantly more ‘fresh’, less ‘animal’, ‘cardboard’, and ‘intense’ aroma than the GrL group. The taste of the yolks from the InL and GrW groups was significantly more ‘fresh’ and less ‘cardboard’‐like compared to the GrL group. The yolks tasted significantly less ‘sulfurous’ in the GrW group than in the GrL group. CONCLUSION: The combination of a high feed intake from a grass–clover pasture and the type of feed allocated is an important factor in relation to the sensory quality of eggs. Thus, a less favourable sensory profile of eggs was found from hens on a grass–clover pasture and fed a normal layer diet. Copyright © 2009 Society of Chemical Industry