Yolk Content Research Articles

تغذية الدواجن لغرض خاص: بيض المائدة أحماض أوميغا 3 الدهنية المتعددة غير المشبعة كغذاء وظيفي: مقالة مراجعة

في بداية القرن الحادي و العشرين تم إعتبار علم تغذية الإنسان وسيلة لتحسين نوعية الحياة و الصحة العامة. دور الغذاء في صحة الإنسان و وعي المستهلكين للأغذية الصحية وجه البحوث نحو انتاج أغذية لها آثار صحية محددة على الوقاية من الأمراض و علاجها. هذه الأغذية أثبتت بشكل مرض أثرها المفيد على واحد أو أكثر من وظائف الجسم، بجانب توفير التغذية الكافية. تسمى هذه الأغذية بالأغذية الوظيفية. إنتاج بيض المائدة الغني بالأحماض الدهنية غير المشبعة أوميغا-3 كغذاء وظيفي هو نموذج جديد في تغذية الدواجن. قدرة الحيوانات وحيدة المعدة على ترسيب الأحماض الدهنية في أنسجتها دون التأثير على القيمة الحسية لهذه المنتجات يعتبر حجر الأساس و نقطة البداية لإنتاج بيض أوميغا-3. الأدبيات المختصة بهذا الموضوع وضعت أساسا قويا لإنتاج هذا النوع من الأغذية الوظيفية. المصادر الغذائية للأحماض الدهنية غير المشبعة المستخدمة في تغذية الدجاج البياض عدلت محتوى هذه الأحماض في صفار البيض مما جعل البيض المنتج مناسبا لتقديمه كغذاء وظيفي. ويمكن زيادة محتوى صفار البيض من هذه الأحماض عن طريق إضافة مصادر علفية غنية بألفا لينولينك مثل بذر الكتان أو غنية ب DHA و EPA مثل زيت السمك و مسحوق السمك.

Effect of dietary supplementation of acid ensiled fish waste on production performance, egg quality and serum biochemistry in layer Japanese quail (Coturnix coturnix japonica)

Five weeks old layer Japanese quail (Coturnix coturnix japonica) birds (180 nos) were randomly distributed into 4 dietary groups with 3 replicates each for 98 days to study the effect of dietary inclusion of acid ensiled fish waste silage on the production performance, egg quality, feed cost, and serum biochemical profile. Fish meal in control diet was replaced by supplementing fish silage at 3%, 6% and 12% of the diet. Significant increase in egg production (p>0.05) and the lowest feed conversion ratio were recorded when birds were fed with 3% silage. But the egg production or feed conversion ratio was not adversely affected by 6% or 12% inclusion of fish silage. Egg quality attributes like weight, shape index, Haugh score, albumen index or yolk index did not differ significantly with the increasing content of silage in the feed. The yolk concentration increased significantly (p>0.05) with increase in fish silage in the diet. The concentration of serum biochemical constituents (total protein, albumen, globulin, cholesterol, triglyceride, alkaline phosphatase, urea and creatinine concentration) did not vary significantly (p>0.05) among the treatments. Serum glucose concentration was the highest in birds fed with 3% fish silage. Lowest cost of feed/kg egg mass was obtained by inclusion of 3% of fish silage in the diet. It was concluded that acid ensilage from freshwater fish waste can replace fishmeal in layer Japanese quail diets without affecting the production of birds besides resulting in reduction of feed cost.

The environmental neurotoxin β-N-methylamino-l-alanine (l-BMAA) is deposited into birds' eggs

The neurotoxic amino acid β-N-methylamino-L-alanine (BMAA) has been implicated in the etiology of neurodegenerative disorders. BMAA is also a known developmental neurotoxin and research indicates that the sources of human and wildlife exposure may be more diverse than previously anticipated. The aim of the present study was therefore to examine whether BMAA can be transferred into birds’ eggs. Egg laying quail were dosed with 14C-labeled BMAA. The distribution of radioactivity in the birds and their laid eggs was then examined at different time points by autoradiography and phosphoimaging analysis. To evaluate the metabolic stability of the BMAA molecule, the distribution of 14C-methyl- and 14C-carboxyl-labeled BMAA were compared. The results revealed a pronounced incorporation of radioactivity in the eggs, predominantly in the yolk but also in the albumen. Imaging analysis showed that the concentrations of radioactivity in the liver decreased about seven times between the 24h and the 72h time points, while the concentrations in egg yolk remained largely unchanged. At 72h the egg yolk contained about five times the concentration of radioactivity in the liver. Both BMAA preparations gave rise to similar distribution pattern in the bird tissues and in the eggs, indicating metabolic stability of the labeled groups. The demonstrated deposition into eggs warrants studies of BMAAs effects on bird development. Moreover, birds’ eggs may be a source of human BMAA exposure, provided that the laying birds are exposed to BMAA via their diet.

Higher growth rate and gene expression in male zebra finch embryos are independent of manipulation of maternal steroids in the eggs

Sexual dimorphism in prenatal development is widespread among vertebrates, including birds. Its mechanism remains unclear, although it has been attributed to the effect of maternal steroid hormones. The aim of this study was to investigate how increased levels of steroid hormones in the eggs influence early embryonic development of male and female offspring. We also asked whether maternal hormones take part in the control of sex-specific expression of the genes involved in prenatal development. We experimentally manipulated hormones’ concentrations in the egg yolk by injecting zebra finch females prior to ovulation with testosterone or corticosterone. We assessed growth rate and expression levels of CDK7, FBP1 and GHR genes in 37h-old embryos. We found faster growth and higher expression of two studied genes in male compared to female embryos. Hormonal treatment, despite clearly differentiating egg steroid levels, had no effect on the sex-specific pattern of the embryonic gene expression, even though we confirmed expression of receptors of androgens and glucocorticoids at such an early stage of development. Thus, our study shows high stability of the early sex differences in the embryonic development before the onset of sexual differentiation and indicates their independence of maternal hormones in the egg.

Liver volatolomics to reveal poultry exposure to γ-hexabromocyclododecane (HBCD)

Hexabromocyclododecane (HBCD) is a critical emerging brominated flame retardant to which consumers can be exposed at high doses through a single food intake. Based on an animal experiment involving 3 groups of laying hens fed during 70 days with a control diet or γ-HBCD-contaminated diets at 0.1 or 10 μg γ-HBCD g−1 feed, this study aims to use the volatolome of biological samples for revealing markers of livestock exposure to HBCD. Liquid chromatography–tandem mass spectrometry was used to monitor the time-course of HBCD levels in bodily samples. Each liver was analyzed by solid-phase microextraction–gas chromatography–mass spectrometry for volatolome profiling. After 70 days, γ-HBCD concentrations in egg yolk, fat, liver and serum reached 54 ± 4, 85 ± 6, 31 ± 6, and 32 ± 4 ng g−1 lw, respectively, for the low exposure level and 4.6+/5.7, 7.8+/6.5, 3.9+/3.0 and 3.9+/6.1 μg g−1 lw, respectively, for the high exposure level. Isomerization of γ-HBCD into α- and β-HBCD was observed in all tissues, at least for the high exposure level. Volatolome data allowed a significant discrimination between control and exposed animals whatever the feed contamination load, demonstrating a liver metabolic response to γ-HBCD exposure. The relevance of the twenty nine volatile exposure markers tentatively identified was discussed in light of literature data.

Exploratory and descriptive study on nutritional characteristics and quality of eggs from Chilean partridge (Nothoprocta perdicaria).

This work aims to contribute more information on tinamou eggs by performing an exploratory and descriptive study of some of their nutritional and quality characteristics. The chemical composition of tinamou egg showed a high protein content in white (85% dry basis) and high lipid concentration in yolk (52% db). The iron (Fe) content in white was higher than hen egg (0.47mg/100g) and this could be associated with the observed pinkish color of the white. As in the hen egg, the major fatty acids in tinamou yolk were: oleic (39%), linoleic (23%) and palmitic (20%). The cholesterol content of tinamou was 21.2mg/g of yolk, and 100g of whole egg provides 589mg of cholesterol. As in the hen egg, tinamou egg white showed high levels of lysine, sulfur-containing amino acids, threonine and valine with respect to the recommended allowance for an adult man. All essential amino acids with the exception of histidine cover the adult requirements. The shell inorganic composition of these eggs is calcium carbonate and the morphology was similar to other avian eggs. Tinamou egg is small and elongated, with a dark brown color. The eggshell is thinner and experiences more deformation but less breaking strength than hen eggshell.

Productive performance and egg quality of laying hens fed diets supplemented with garlic and onion extracts

SUMMARY The study was aimed at evaluating the effect of supplementing a diet for laying hens with onion and garlic extracts on their productive performance and egg quality. Two-hundred-sixteen laying hens were divided into 3 groups: standard diet, diet with a 0.0032% addition of onion extract, and diet with a 0.0032% addition of garlic extract. The egg production rate, egg weight, and feed conversion ratio were monitored within the first 17 wk of the laying period. In wk 6, 8, 10, 12, 14, and 16 of the laying period, eggs were analyzed for: weight, weight to yolk ratio, yolk color, albumen quality, and eggshell quality. In wk 7 and 15 of the laying period, analyses were conducted for: yolk color, consistency, aroma, and taste of boiled eggs. The addition of a garlic extract had a positive effect on the production rate in the initial and peak egg-laying period, and significantly determined the aroma and, in the further stage of the production process, also taste of boiled eggs. Administration of the diet with onion extract to hens caused them to begin the egg-laying period later but laying heavier eggs, with a higher content of egg yolk and better quality of albumen. The analysis of the productive performance of hens and quality of eggs indicates the advisability of applying the extract from garlic in commercial flocks of laying hens. In the future, it seems substantiated to analyze the effect of extract supplementation at the end of the laying period.

Isolation of anti-idiotype minor capsid Human papillomavirus type 16 (HPV 16 L2) IgY from egg yolk as immunogen of HPV vaccine

Nawangsih EN, Paryati SPY, Effendy JS, Sudigdoadi S, Sahiratmadja E, Hilmi D, Sovia E. 2017. Isolation of anti-idiotype minor capsid Human papillomavirus type 16 (HPV 16 L2) IgY from egg yolk as immunogen of HPV vaccine. Nusantara Bioscience 9: 282-287. A potential strategy for the production of safe protective vaccines for human papillomavirus (HPV) infection is to utilize antiids. Meanwhile, hyperimmunized hens could provide a convenient of specific immunoglobulin in their yolks (IgY). This study aimed to isolate IgY specific to anti-idiotype HPV 16 L2 from egg yolk which could be used for future alternative immunogen for HPV vaccine. Antibody anti-idiotype derived from chicken egg yolk that chickens immunized by HPV 16 L2 antibody. The antibodies were purified from immunized chicken egg yolk, then electrophoresis it using SDS-PAGE method to determine the molecular weight of IgY. To determine an amount of protein, we used fluorometer method and to confirm an existence of specific IgY using ELISA method. The results showed that the IgY preparation dissociated into three protein major bands with molecular weights of 180; 65; and 25 kD. The IgY and IgY specific concentration in eggs yolk increased until 8th week. After 8th week the levels decreased gradually. Samples derived from chickens immunized showed significantly higher concentrations of IgY and IgY specifics than control (p<0.05). These results suggested that chicken IgY could be a practical strategy in large-scale production of specific antibody anti-idiotype HPV 16 L2 for HPV Vaccine.

Goose FMO3 gene cloning, tissue expression profiling, polymorphism detection and association analysis with trimethylamine level in the egg yolk

Flavin-containing monooxygenase 3 (FMO3) plays a critical role in catalyzing the conversion of trimethylamine (TMA) to trimethylamine-N-oxide (TMAO) in vivo. Despite the well-documented association between FMO3 mutations and a ‘fishy’ off-flavor eggs in chicken and quail, little information is available regarding the molecular characteristic of goose (Anser cygnoides) FMO3 and its relationship with the yolk TMA content. To fill these gaps, we cloned the full-length cDNA sequence of goose FMO3, which comprised 1851bp encoding 531 amino acids. FMO3 mRNA was dramatically expressed in liver than in other tissues in the geese. Eight single nucleotide polymorphisms (SNPs) were detected in the entire coding region. The CC genotype at the T669C site, GG at the A723G site, and AA at the G734A site of FMO3 were highly significantly associated with elevated TMA content in goose egg yolk (P<0.001). Carriers of the A allele of G734A or C allele of T885C had yolk TMA content that had a high probability of being elevated after feeding with additional choline chloride (P=0.0429, OR=4.1300, 95%CI=1.0390–16.4270, and P=0.0251, OR=4.6060, 95%CI=1.1620–18.2620, respectively). This work lays a foundation for studying the function of FMO3 and yolk TMA content in goose. However, studies using larger sample sizes and more goose breeds are required to determine whether the fishy off-flavor trait exists in goose.

Dietary choline and phospholipid supplementation enhanced docosahexaenoic acid enrichment in egg yolk of laying hens fed a 2% Schizochytrium powder-added diet

The aim of this study was to evaluate the effect of dietary phospholipid supplementation on laying hen performance, egg quality, and the fatty acid profile of egg yolks from hens fed a 2% Schizochytrium powder diet. Three-hundred-sixty 28-wk-old Hy-line W-36 laying hens were randomly allocated to one of the 5 dietary treatments, each treatment with 6 replicates of 12 birds each. All diets included 2% Schizochytrium powder (docosahexaenoic acid [DHA], 137.09 mg/g). The control group was not supplemented with any additional phospholipids, whereas the other 4 experimental diets were supplemented with 1,000 mg/kg choline (CHO), 1,000 mg/kg monoethanolamine (MEA), 1,000 mg/kg lysophosphatidylcholine (LPC), or 500 mg/kg LPC + 500 mg/kg MEA (LPC + MEA). The experimental diets were isocaloric (metabolizable energy, 11.15 MJ/kg) and isonitrogenous (crude protein, 16.60%). The feeding trial lasted 28 days. Laying hen performance and egg quality were not affected (P>0.05) by the diets used. The monounsaturated fatty acid (MUFA) level was reduced in the LPC group at d 28 (P < 0.01), whereas the polyunsaturated fatty acid (PUFA) level was increased (P < 0.05). The omega-6 (n-6) PUFA level of the egg yolks in the LPC group had a trend to increase in comparison to the control (P = 0.07). The CHO and LPC groups had higher omega-3 (n-3) PUFA and DHA levels and lower n-6/n-3 ratios than the other groups at d 28 (P < 0.01). The DHA content in egg yolk reached a plateau after the laying hens consumed the experimental diets for 14 days, and higher yolk DHA contents were observed in the CHO and LPC groups as compared with the other groups at d 14. It was concluded that dietary choline supplementation for more than 14 d enhanced egg yolk enrichment with n-3 PUFA and DHA when laying hen diets were supplemented with 2% Schizochytrium powder. All the diets had no adverse effect on hen performance, egg quality, or egg components under the experimental condition.

Digestive enzyme ratios are good indicators of hatchling yolk reserve and digestive gland maturation in early life stages of cuttlefish Sepia officinalis L.: application of these new tools in ecology and aquaculture.

In Sepia officinalis (Linnaeus, 1758), the digestive gland matures during the first month post-hatching, while a shift from intracellular acid to extracellular alkaline digestion occurs. The purpose of this study was to investigate the possibility of using enzymatic ratios for the description of digestive system maturation in early life stages of S. officinalis. Second, it is intended to apply these new tools as eco-physiological indicators for understanding the impact of cuttlefish eggs' life history from different spawning sites of the English Channel on digestive performance of juveniles. An experimental rearing was performed over 35days after hatching (DAH) on juveniles from wild collected eggs in 2010 and 2011. Four digestive enzyme activities and their ratios [i.e., trypsin, cathepsin, acid (ACP), and alkaline (ALP) phosphatase, ALP/ACP, and trypsin/cathepsin] were studied along with histological features (e.g., internal yolk surface and digestive gland development). The two enzyme ratios were good indicators of digestive system maturation allowing the study of the digestive gland's development. They were highly correlated to juveniles' weight increase and histological features of the gland in early DAH. These ratios described more accurately the shift occurring between the intracellular acid and the extracellular alkaline modes of digestion in S. officinalis and were more specific than separated enzyme activities. Their application as eco-physiological tools revealed that enzyme ratios reflected yolk content and digestive gland development in new hatching juveniles. Finally, ALP/ACP ratio was shown to be a powerful tool to describe growth performance of S. officinalis which is useful for aquaculture optimization.

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

Abstract Sixty Hy-line brown hens were randomly assigned to four barns ( n = 4) to investigate the effects of cholecalciferol (vitamin D₃) versus 25-hydroxyvitamin D 3 (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 Industrial relevance Vitamin 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.

Lipolysis and oxidation of lipids during egg storage at different temperatures

The aim of this study was to investigate lipolysis and lipid oxidation of stored eggs at different temperatures (4 and 22°C) by evaluating the changes in physicochemical index, lipid profiles, enzymatic activity, and oxidative index. The results showed that the changes in physicochemical index were more significant at 22°C than at 4°C. Weight loss, moisture content, and pH of egg yolk increased significantly (P &amp;lt; 0.05), whereas the yolk index decreased during storage. However, there was no significant difference in lipid profiles between 4 and 22°C storage temperature. The lipid composition analysis demonstrated that lipid hydrolysis took place during egg storage and resulted in a marked decrease of PL and increase of FFA. It was also found that the content of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylinositol (PI) decreased significantly during storage. The correlation analysis showed that the lipid degradation is significantly positively related to lipase activity (P &amp;lt; 0.05), and the marked changes of lipid fractions are results of both hydrolysis and oxidation. It can be concluded that the egg physicochemical index and lipase activity were greatly influenced by temperature during storage, but the yolk lipid stability was not significantly influenced by storage temperature.

Effects of Soy Lecithin Extender on Dog Sperm Cryopreservation

ABSTRACTSemen cryopreservation is an essential biotechnology in canine reproduction and during the cryopreservation process commonly egg yolk are used. The discrepancy in the egg yolk composition and the potential risk of disease dissemination are obstacles for semen exportation and use. Therefore, studies aiming to substitute egg yolk are extremely important. In this context, soy lecithin contains a low-density lipoprotein fraction, is an interesting alternative. Thus, the objective of this study was to compare extenders based on soy lecithin (several concentrations and forms) with egg yolk during the cryopreservation process of dog sperm. For this purpose, we used twelve dogs. Semen was evaluated at different time points (after refrigeration, glycerolization, and thawing), by motility analysis (CASA) and functional tests (e.g., membrane integrity—eosin/nigrosin, acrosome integrity—fast green/Bengal rose, mitochondrial activity—3’3 diaminobenzidine, Chromatin susceptibility to acid-induced denaturation—SCSA, and susceptibility to oxidative stress—thiobarbituric acid reactive substances). The results indicated that egg yolk and lower concentrations of lecithin had similar effects on mitochondrial activity and motility. Thus, soy lecithin is a potentially viable alternative to egg yolk for the cryopreservation of dog semen.

The effect of essential oils on quality and mineral composition of eggshell

The effect of essential oils on quality and mineral composition of eggshell

Metals in Blood and Eggs of Green Sea Turtles (Chelonia mydas) from Nesting Colonies of the Northern Coast of the Sea of Oman

The green sea turtle (Chelonia mydas) has been a species of global concern for decades. In this study, heavy metals (mercury: Hg; Cadmium: Cd; Lead: Pb; Copper: Cu; and Zinc: Zn) were measured in blood and three egg fraction of green sea turtles nesting on the northern coast of Sea of Oman. Heavy metals concentrations in blood, yolk, albumen, and egg shell ranged between 0.16-36.78, 0.006-33.88, 0.003-4.02, and 0.002-6.85μg/g (ww), respectively. According to the results, all heavy metals found in blood samples (n=12) also were detected in the various parts of the eggs (n=48). Moreover, there were no significant differences between concentrations of heavy metals in different clutches laid in a nesting season. However, Pb concentrations in blood samples significantly increased in later clutches (p<0.05), whereas Cu concentrations in blood samples exhibit a declining trend (p<0.05). These results reveal the existence of maternal transfer phenomenon in green sea turtles on the northern coast of Sea of Oman. Results of this study suggest that heavy metals could be one of the factors influencing reductions in fertilization and hatching success. Results also indicate that green sea turtle on the northern coast of Sea of Oman have high capacity in rapid response and detoxification of heavy metals and/or from the low exposure levels of these turtles to the heavy metals. Further research is required concerning the effects of heavy metals on green sea turtles, especially on their possible influence of fetal development of turtles.

Evidence on the stability of histone H1.a polymorphic variants during selection in quail

Abstract. The goal of this work was to check whether selection for quantitative traits may cause a change in the histone H1 allelic complement and whether it can therefore be considered a modulator of histone H1-dependent chromatin functioning. For this purpose, a fluctuation of histone H1.a polymorphic variants was analyzed among a non-selected (control) quail line and the line selected for a high cholesterol content in the egg yolk. The histone H1.a was found to be polymorphic due to its differential migration rate in the AU-PAGE (acetic acid–urea polyacrylamide gel electrophoresis). Based on this, two H1.a isoforms (H1.a1 and H1.a2) that form three phenotypes (a1, a2 and a1a2) were distinguished in the quail lines tested. A comparably expressed (p &gt; 0. 05) and low relative variable (coefficient of variation, CV &lt; 0. 25) histone H1.a phenotypes were in agreement with Hardy–Weinberg equilibrium (HWE) in both the non-selected (χ2 = 1. 29, p = 0. 25) and selected (χ2 = 1. 9, p = 0. 16) quail line. The similarity among quail lines was assessed based on the equal distribution of histone H1.a phenotypes (χ2 = 1. 63, p = 0. 44) and alleles (χ2 = 0. 018, p = 0. 89) frequency in both quail lines tested. This indicates that selection does not affect the histone H1.a polymorphic variants. The stability of histone H1.a during selection might suggest that likely chromatin processes coupled to the selected trait are not linked to the activity of histone H1.a.

Comparative omega-3 fatty acid enrichment of egg yolks from first-cycle laying hens fed flaxseed oil or ground flaxseed

When laying hen diets are enriched with omega-3 polyunsaturated fatty acids to generate value-added eggs for human consumption markets, concentrations of alpha-linolenic (ALA), eicosapentaenoic (EPA), and docosahexaenoic acids (DHA) in the yolk can reach 250mg/50g whole egg. Flaxseed, a rich source of ALA, is commonly used for omega-3 enrichment; however, the impact of dietary flaxseed source (extracted oil vs. milled seed) on fatty acid transfer to egg yolk in laying hens is unknown. Therefore, transfer of ALA, EPA, and DHA into egg yolk from extracted flaxseed oil or milled flaxseed was evaluated in Hy-Line W-36 laying hens over an 8-week feeding period (25 to 33 wk old). Hens (n = 132) were randomly housed with 3 birds/cage (4 replicates/treatment) for each of the 11 treatment groups. Diets were isocaloric and consisted of a control diet, 5 flaxseed oil diets (0.5, 1.0, 2.0, 3.0, or 5.0% flaxseed oil), and 5 milled flaxseed diets (calculated flaxseed oil concentration from milled flaxseed 0.5, 1.0, 2.0, 3.0, 5.0%). Increasing dietary concentrations of flaxseed oil and milled flaxseed resulted in increased ALA, EPA, and DHA concentration in egg yolk, and fatty acid deposition from flaxseed oil was 2 times greater compared to milled flaxseed when fed at the same dietary inclusions (P < 0.01). Egg yolk EPA and DHA concentrations were not different due to oil or milled source (P = 0.21); however, increasing dietary inclusion rates of flaxseed oil from either source increased yolk EPA and DHA (P < 0.01). Hens fed either flaxseed oil or milled flaxseed resulted in reduced BW change as dietary concentrations increased (P = 0.02). Feed efficiency increased as flaxseed oil increased in concentration, while feeding milled flaxseed decreased feed efficiency (P = 0.01). Analysis of the nitrogen corrected apparent metabolizable energy of flaxseed oil resulted in 7,488kcal/kg on an as-fed basis. Dietary flaxseed oil improved feed efficiency and increased ALA deposition into yolk compared to a milled source, demonstrating flaxseed oil to be a viable alternative for ALA egg enrichment.

Effects of breeder age, strain, and eggshell temperature on nutrient metabolism of broiler embryos

Breeder age and broiler strain influence the availability of nutrients and oxygen through yolk size and eggshell conductance, and the effects of these egg characteristics on nutrient metabolism might be influenced by eggshell temperature (EST). This study aims to determine effects of breeder age, strain, and EST on nutrient metabolism of embryos. A study was designed as a 2×2 × 2 factorial arrangement using four batches of in total 4,464 hatching eggs of 2 flock ages at 29 to 30 wk (young) and 54 to 55 wk (old) of Ross 308 and Cobb 500. EST of 37.8 (normal) or 38.9°C (high) was applied from incubation day 7 (E7) until hatching. Wet yolk weight was determined mainly by breeder age (P = 0.043). Energy content in yolk (P = 0.004) and albumen + yolk (P = 0.005) were higher in old flock eggs than in young flock eggs, but did not differ between broiler strains. Eggshell conductance was higher in Ross 308 eggs than in Cobb 500 eggs (P < 0.001). Old flock embryos used more energy (P = 0.046) and accumulated more energy into yolk free body mass (YFBM; P = 0.030) than young flock embryos, whereas heat production (HP), energy lost, and efficiency of converting energy used to YFBM (EYFB) did not differ. Ross 308 embryos used more energy (P = 0.006), had a higher energy lost (P = 0.010), and a higher HP between E15 to E18 (P < 0.05) than Cobb 500 embryos. Energy content in YFBM did not differ between strains and EYFB (P = 0.024) was lower in Ross 308 than in Cobb 500. High EST resulted in higher HP than low EST from E11 to E15 (P < 0.05), but not after E15. Amount of energy used (P = 0.006) and energy accumulated in the YFBM (P < 0.001) was lower for embryos incubated at an EST of 38.9 than that of 37.8°C, whereas EYFB did not differ. In conclusion, breeder age, broiler strain, and EST differentially influence embryonic metabolism and particularly the availability of oxygen could have contributed to these differences.

Nutritional Quality of Eggs of Amberlink and Hyline Layers Fed on Different Levels of Provitamin A-Biofortified Maize

ABStRACt The study was conducted to determine the interaction of types of maize (Provitamin A-biofortified maize (PABM) versus white maize) and strain of laying birds (Amberlink and Hyline) on nutritional quality of eggs. Twenty-one of each of Amberlink and Hyline laying hens were fed on three diets for 30 days. Birds were distributed in a 3 × 2 factorial arrangement constituting three diets (0, 50 or 100 % of PABM) and two strains (Amberlink & Hyline). There was a diet × strain interaction on egg shell weight, average daily feed intake, egg production, egg weight and egg shell thickness. Eggs produced by layers under 100 % PABM had lighter eggshell weight and lower eggshell percentage. In contrast, eggs produced by layers under 50 % PABM diet had signi-ficantly higher eggshell percentage, heavier egg shell weight and thicker eggshell. As the level of PABM increased, the yellow and red hue (Hunter a* and b* values) significantly increased while the lightness values (Hunter L* values) decreased. As the level of PABM in the ration increased, the vitamin A content of the egg yolk also significantly increased. Assimilation of vitamin A from feed to egg yolk in Amberlink and Hyline hens was similar. Hence, egg enrichment with vitamin A can be achieved by using PABM in layers ration. The use of high level of PABM had a negative effect on the eggshell quality traits.