Yolk Content Research Articles

Non‐analytical methods for the estimation of total yolk carotenoids in passerine eggs

Carotenoids are essential antioxidant micronutrients. Oviparous species acquire carotenoids from their food and deposit them in the egg yolk, where they support embryonic development. The total carotenoid concentration in the egg yolk is typically measured analytically, which requires time, equipment and expertise, and can limit the sample available for other measurements, at least in species laying small eggs. Here we evaluate whether yolk colour can be used as a reliable alternative measure for total yolk carotenoid concentration. We compare two non‐analytical methods, digital photography and visual colour scoring, using eggs from a wild population of Blue Tits Cyanistes caeruleus. Yolk hue estimated from digital photographs correlated more strongly with total yolk carotenoid concentration measured by high‐performance liquid chromatography (HPLC) than did the visually assessed colour score based on a Yolk Colour Fan. Previous results based on HPLC measurements of total carotenoid concentration could be reproduced using yolk hue measurements. The results suggest that measuring yolk hue is a suitable proxy for assessing natural variation in total yolk carotenoid concentration in eggs of free‐living birds.

The effect of BAV addition as feed additive in laying hen ration on quality and chemical composition of egg

This study aimed to investigate the effect of BAV (blend of 9-natural EO mixed with iodized salt) as feed additive in the ration of laying hens, on the quality and chemical compositions of egg. Thirty laying hens (Lohmann Brown, aged 50 weeks) were divided into two groups (control and 2 g/kg BAV) and given for 6 six weeks. Data on hen daily average (HDA), feed intake, feed conversion ratio (FCR), egg quality (weight, length, width, albumen high and width, yolk high and width, yolk colour, shell thickness, shell weight and Haugh unit) and egg’s chemical composition (yolk cholesterol, yolk protein, albumen protein, xanthophyll) were analyzed. The results showed that BAV significantly increased HDA (P<0.05), and had no effect on feed intake and FCR. The addition of BAV increased yolk wide (P<0.05) and tend to improved egg mass and albumen width, but no difference on egg quality observed. The BAV significantly (P<0.05) decrease cholesterol content of yolk, but no effect to xanthophyll level and both of protein content of yolk and albumen. It is concluded that the addition of BAV as feed additive in the ration of laying hens has potential to improve the quality and chemical compositions of egg.

Effects of Ginger Extract on Laying Performance, Egg Quality, and Antioxidant Status of Laying Hens.

Simple SummaryThe application of in-feed antibiotic growth promoters was banned in many countries due to their negative effects, and several kinds of feed additives were widely investigated as antibiotic alternatives, in which natural plant-derived products received much attention due to their environmentally friendly properties and numerous biological activities. Ginger (Zingiber officinale Roscoe), a widely used herbal medicine and spice, was proven to have potential as an antibiotic alternative in poultry feed, but there is little literature on the efficacy of ginger extract (GE), which has concentrated bioactive compounds with high bioavailability. Our results showed that dietary GE supplementation increased egg weight, improved egg quality, and reduced the yolk cholesterol content of laying hens. Decreased serum activities of alanine transaminase and aspartate transaminase and improved antioxidant status were observed in the GE group. Our study demonstrated the potential benefits of GE in laying hens.The objective of this study was to investigate the effects of ginger extract (GE) as a dietary supplement for laying hens. A total of 40-week-old 288 Hyline Brown laying hens were randomly divided into two groups with six replicates, and fed a basal diet with or without 100 g/t GE for eight weeks. Dietary GE supplementation increased egg weight, albumin height, and Haugh unit of eggs, and decreased yolk cholesterol content and activities of alanine transaminase and aspartate transaminase in serum at eight weeks. Moreover, GE resulted in higher total superoxide dismutase (T-SOD) activity and lower malondialdehyde (MDA) content in yolk at four and eight weeks and in serum. It was concluded that GE was effective in increasing egg weight and improving the egg quality and antioxidant status of laying hens.

The effect of storage temperature on the metabolic profiles derived from chicken eggs

Metabonomic profiling, using High Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (HPLC-Q-ToF-MS), was adopted in this study to uncover differences in the small molecule profiles of egg yolks, between two sets of six eggs that were stored at 5 °C and 23 °C for five weeks. Choline, a compound that has previously been shown to have potential use as a biomarker of egg age, was observed to have a significantly lower abundance in the yolks of eggs that were stored at 5 °C for five weeks compared to eggs stored at 23 °C for the same length of time. A follow-up targeted study observed that the previously discovered trend of increasing choline concentration in egg yolk, with increasing egg age, is not repeatable when the eggs are stored at 5 °C rather than 23 °C. It concluded that, by refrigerating eggs at 5 °C, the accurate prediction of egg age using choline as a biomarker can be prevented.

Carrot leaves improve color and xanthophyll content of egg yolk in laying hens but are not as effective as commercially available marigold fortificant

Yellow and orange egg yolks are good sources of xanthophyll carotenoids, consumption of which is associated with health benefits, such as cancer prevention, eye health, and bone health. Industrial feed fortificants used to improve egg yolk color and carotenoid concentration typically are derived from marigold flowers. Green leafy vegetables are also concentrated sources of the xanthophylls lutein and zeaxanthin (L+Z), but they have not been rigorously evaluated in laying hen feeds as a yolk colorant. The addition of food manufacturing byproducts, including carrot leaves, to animal feed is a promoted method of improving animal nutrition. The ability of dehydrated carrot leaves to improve egg yolk color and L+Z concentration was evaluated by feeding laying hens (n = 40) white maize-based feeds fortified with 2 different dehydrated carrot leaves, marigold as a positive control, or no fortificant as a negative control for 28 D. After a 7-D washout period, the hens were separated into 4 groups, and eggs were collected every other day. Yolks were analyzed by using a portable colorimeter to define the color space and by ultra-performance liquid chromatography to determine the carotenoid profile. Carotenoid concentration rapidly declined from day 0 to 8, confirming adequate washout conditions. The white maize negative control (WM) day 28 lutein concentration (3.59 ± 0.51nmol/g) was significantly less than orange-carrot leaf-treated (OCL) (5.34 ± 0.36nmol/g) and red-carrot leaf-treated hens (RCL) (5.92 ± 1.00nmol/g) in addition to the marigold-treated hens (MG). However, MG was significantly higher than both leaf-treated groups. From day 8 (3.93 ± 0.74nmol/g) to 28 (9.32 ± 1.66nmol/g), MG had the largest increase in lutein and was the only treatment to surpass day 0 initial concentrations (8.50 ± 1.64nmol/g). A similar trend was observed for zeaxanthin and was reflected in the color space.

The effect of zinc, iron, calcium, and copper from organic sources in pheasant diet on the performance, hatching, minerals, and fatty acid composition of eggs

The paper presents findings about how the substitution of calcium, iron, zinc, and copper salts with glycine chelates affects specific reproductive parameters of pheasants, the hatching potential and nutritional components of pheasant eggs, and the fatty acid profiles and cholesterol content in pheasant yolk. 4 groups were created for the experiment: the control, in which the birds received a feed containing standard calcium, iron, zinc, and copper salts, and 3 experimental groups in which chelates were used to replace 25, 50, and 75% of the mineral salts. The group with the 75% chelate share was not supplemented with the salts, and cholecalciferol was replaced with calcitriol. The groups included pheasant females (7 birds) and 1 male, respectively, and were maintained in outdoor aviaries. The birds were administered granulated feed mixes ad libitum, with free access to water. Their feed intake was recorded each day. The birds were weighed at the beginning and end of the egg-laying period. The eggs were collected throughout the egg-laying period, and the eggs gathered at the culmination of the egg-laying period were used for hatching. The eggs were morphometrically analyzed and the hatching process and subsequent hatchling survival rates were investigated. Nutritional components in the eggs were determined, and the fatty acid profiles and cholesterol content were assayed in the yolk. The results showed the use of Ca, Fe, Zn, and Cu chelates in place of salts in the pheasant brood hen diet had contributed to enhancing the egg-laying performance, with a concurrent fall in the size and weight of the eggs. The highest egg-laying performance, with the lowest egg weight, was observed in the group that consumed the highest (75%) share of mineral chelates and received calcitriol supplementation. This corresponded with the highest incubation yield and hatchling survival. The thickest shells and highest crude ash percentages were identified in the eggs of the pheasant group that received a 50% by 50% proportion of salts and glycine chelates. In comparison with the control birds that received the mineral salts, the yolk of the pheasants that consumed the feed with the 75% share of calcitriol and Ca, Fe, Zn, and Cu chelates had a higher percentage of n-6 and n-3 polyunsaturated fatty acids (PUFAs), with a far more advantageous n-6/n-3 proportion. No differences related to the source and levels of Ca, Fe, Zn, and Cu in the feed were observed in the cholesterol content of the pheasant yolk.

CRYOPRESERVATION OF KAMPUNG ROOSTER SEMEN USING EGG YOLK DILUENT FROM FOUR TYPES OF POULTRY WITH DIFFERENT CONCENTRATIONS

The aim of this study was to determine the type and the best concentration of egg yolk in maintaining the quality of kampung rooster spermatozoa during cryopreservation. This study used a completely randomized factorial pattern design with the first factor was the type of egg yolk (purebred chicken, kampung chicken, duck, and quail) and the second factor was the concentration of egg yolk (5%, 10%, and 15%). Semen was collected from twelve kampung roosters using massage method. Immediately after collection, the semen was evaluated macroscopically and microscopically. Semen with more than 70% motility was used in this study. The semen was diluted, packed in a ministraw, equilibrated, and frozen using liquid nitrogen vapor and stored in a liquid nitrogen container for 24 hours. Observation of spermatozoa motility was carried out in fresh semen, diluted semen, after equilibration and after thawing with four replications. The results showed that the type of egg yolk treatment had no effect (P0.05) on the recovery rate and motility of spermatozoa before and after cryopreservation, but egg yolk concentration had a highly significant effect (P0.01) on the quality of spermatozoa. Egg yolks in 10-15% concentration had spermatozoa motility and recovery rate higher than egg yolk with 5% concentration. In conclusion, purebred chicken egg yolk, kampung chicken egg yolk, duck egg yolk, and quail egg yolk each in diluent can be used to maintain the quality of kampung rooster spermatozoa at a concentration of 10-15% during cryopreservation.

Effect of diluent type, cryoprotectant concentration, storage method and freeze/thaw rates on the post-thaw quality and fertility of cryopreserved alpaca spermatozoa

This study compared protocols for cryopreservation of ejaculated, papain-treated alpaca spermatozoa. This included different concentrations of egg yolk (EY; 5, 10 or 15%) and glycerol (2, 5 or 10%), diluent types (SHOTOR, lactose, skim milk or INRA-96™), freeze rates (2, 4 or 8 cm above liquid nitrogen; LN), thaw rates (37 °C for 1 min or 42 °C for 20 sec) and storage vessels (pellets, 0.25 mL straws or 0.5 mL straws). Spermatozoa were assessed pre-freeze and 0, 30, 60 and 90 min post-thaw. Forty-one hembras were inseminated with either fresh, papain-treated or frozen-thawed spermatozoa. Motility was affected by EY concentration (P < 0.001), diluent type (P < 0.001), freeze rate (P = 0.003) and storage vessel (P = 0.001). Viability was affected by EY concentration (P < 0.001), diluent type (P < 0.001), storage vessel (P = 0.002) and thaw rate (P = 0.03). For artificial insemination (AI), semen was diluted 1:3 in a lactose-based diluent, with 5% EY and glycerol. Freezing was in 0.5 mL straws, 2 cm above LN for 4 min then thawing at 37 °C for 1 min. Pregnancy rates of those ovulated (n = 26) were not different (1/5 fresh, 1/4 papain-treated, 0/17 frozen-thawed; P = 0.10). Pregnancy can be achieved after AI with papain-treated spermatozoa. Further work is needed to determine the optimal dose, timing and location for insemination.

Nutritional modulation of the antioxidant capacities in poultry: the case of vitamin E.

Commercial poultry production is associated with a range of stresses, including environmental, technological, nutritional, and internal/biological ones, responsible for decreased productive and reproductive performance of poultry. At the molecular level, most of them are associated with oxidative stress and damages to important biological molecules. Poultry feed contains a range of feed-derived and supplemented antioxidants and, among them, vitamin E is considered as the "headquarters" of the antioxidant defense network. It is well-established that dietary supplementation of selenium, vitamin E, and carotenoids can modulate antioxidant defenses in poultry. The aim of the present paper is to present evidence related to modulation of the antioxidant capacities in poultry by vitamin E. Using 3 model systems including poultry breeders/males, semen, and chicken embryo/postnatal chickens, the possibility of modulation of the antioxidant defense mechanisms has been clearly demonstrated. It was shown that increased vitamin E supplementation in the breeder's or cockerel's diet increased their resistance to various stresses, including high polyunsaturated fatty acids (PUFA), mycotoxin, or heat stress. Increased vitamin E supplementation of poultry males was shown to be associated with significant increases in α-tocopherol level in semen associated with an increased resistance to oxidative stress imposed by various external stressors. Similarly, increased vitamin E concentration in the egg yolk due to dietary supplementation was shown to be associated with increased α-tocopherol concentration in the tissues of the developing embryos and newly hatched chicks resulting in increased antioxidant defenses and decreased lipid peroxidation. Furthermore, increased vitamin E transfer from the feed to egg yolk and further to the developing embryo was shown to be associated with upregulation of antioxidant enzymes reflecting antioxidant system regulation and adaptation. The role of vitamin E in cell signaling and gene expression as well as in interaction with microbiota and maintaining gut health in poultry awaits further investigation.

Impact of Dietary Organic Mineral Supplementation on Reproductive Performance, Egg Quality Characteristics, Lipid Oxidation, Ovarian Follicular Development, and Immune Response in Laying Hens Under High Ambient Temperature.

The objectives of this study were to investigate the impact of dietary organic mineral mixture (manganese, zinc, and copper) supplementation on reproductive performance, egg quality characteristics, and immune response in laying hens under high ambient temperature. Hens were randomly divided into three treatments: (1) control (basal diet without organic mineral mixture (Mn, Zn, and Cu) supplementation); (2) basal diet + 0.5g/kg of organic mineral mixture; and (3) basal diet + 1g/kg of organic mineral mixture from 30 to 38weeks of age. Hen-day egg production and egg mass were significantly increased by dietary supplementation of 1g/kg of organic mineral mixture, while feed intake was not affected; therefore, feed conversion ratio (FCR) was significantly improved (P < 0.01). Egg weight, albumen width, shell weight, and shell thickness were significantly increased by the dietary treatments. Serum total cholesterol and glucose were significantly decreased by organic mineral mixture supplementation. Interestingly, yolk contents of total cholesterol and malondialdehyde (MDA) were significantly decreased. Yolk contents of Zn and Cu were significantly increased, while Mn was numerically increased (P > 0.05). Dietary organic mineral mixture supplementation improved the antibody titers against avian influenza H9N1 significantly (P < 0.05) and Newcastle disease virus numerically (P > 0.05) in comparison with the control diet. It might be concluded that the inclusion of organic mineral mixture (Mn, Zn, and Cu) enhanced reproductive performance, shell quality characteristics, plasma profile, yolk mineral concentration, yolk lipid oxidation, and immune response in laying hens under high ambient temperature.

Phase separation in ternary composite cold-set gel of egg yolk/κ-carrageenan/xanthan: Study on rheological and proton mobility properties

The effects of sodium tripolyphosphate and sugar on cold-set gel properties of egg yolk/κ-carrageenan/xanthan gum mixed dispersions were investigated by zeta potential, rheological measurements, gel textural analysis and low-field nuclear magnetic resonance (LF-NMR). As the yolk content increased to the 5 g/100 mL in aqueous systems, phase separation of mixed gel could be observed, due to the relatively rough gel appearance. Furthermore, the addition of phosphate could significantly improve the phase separation of mixed gels by elevating the pH and reducing zeta potential. The increase in the content of yolk and sugar brought an enhancement in gel storage modulus, while the addition of phosphate induced a dramatic decrease in the gelation rate of mixed gels. Textural analysis confirmed that hydrogen bonding interaction was the important force, which determined gel strength of the ternary composite cold-set gelation system. The result of LF-NMR revealed that there was a negative correlation between the decrease of proton mobility of immobilization water and the increase of gel strength in different sample series.

Alterations in lycopene concentration and Z-isomer content in egg yolk of hens fed all-E-isomer-rich and Z-isomer-rich lycopene.

Effects of feeding lycopene isomers to laying hens on egg qualities such as lycopene concentration and color of the yolk were investigated. Firstly, to evaluate the dietary transfer of lycopene to egg yolk, (all-E)-lycopene-rich diets (lycopene content, 100, 200, or 300mg/kg diet) were fed to hens for 21days. Lycopene in egg yolk could be detected after 4days or more from the start of feeding, and the lycopene concentration increased according to the feed amount and period. Even though most of the dietary lycopene was the all-E-isomer, more than 65% of lycopene in egg yolk was present as Z-isomers. Thus, the effect of lycopene Z-isomer content in the diet (lycopene content, 200mg/kg diet; lycopene Z-isomer content, 35.1% or 61.3%) on egg qualities was investigated. As the Z-isomer content increased, the lycopene concentration in the egg yolk increased, for example, when fed a diet rich in Z-isomers (61.3%), the lycopene concentration in the egg yolk was approximately three times higher than when fed the (all-E)-lycopene-rich diet for 21days. The results indicated that Z-isomers of lycopene had higher bioavailability and/or higher transfer efficiency to the egg yolk than the all-E-isomer.

Meat Quality on Sentul Cocks with Different Immunoglobulin Yolk Concentrations

&lt;p class="abstrak2"&gt;Sentul cocks is one of the native chicken breeds in Indonesia which is originally raised by Villagers in Ciamis District, West Java. Healthy chicken cells can function properly, especially in the metabolic process. Healthy chickens are expected to produce better muscle development. IgY is a protein molecule substance that can neutralize a number of microorganisms that cause infection. The purpose of this study was to evaluate the effect of IgY concentration on physicochemical and organoleptic qualities of meat. This study used 20 cocks, 4th month ages, consist of 2 treatments (IgY concentrations above 9.30 ± 0.45 mg mL&lt;sup&gt;-1&lt;/sup&gt; and IgY concentrations below 9.30 ± 0.45 mg mL&lt;sup&gt;-1&lt;/sup&gt;). The variable observed include physicochemical and organoleptic quality of meat. The study was used completely randomized design. Data were analyzed by t-test. The result concluded that cocks with concentrations above 9.30 ± 0.45 mg mL&lt;sup&gt;-1&lt;/sup&gt; produced meat with lower malonaldehyde. The low content of malonaldehyde in meat shows that the meat produced is healthier.&lt;/p&gt;

Preparation and characterization of hen egg proteins-soybean protein isolate composite gels

The physicochemical properties, rheology, texture, water state and microstructure of gels formed from different ratio of egg proteins and soybean protein isolate were investigated. Results showed that composite solution that contained 75% egg proteins had the highest protein surface hydrophobicity while the biggest solubility was found when the proportion of egg proteins was 25%. Solid content and total sulfhydryl groups content before centrifugation increased as the proportion of egg proteins raised while total sulfhydryl groups content after centrifugation had less fluctuations because of the changes of protein solubility. Egg proteins-soybean protein isolate composite solutions had various growth ratio of G’ during different stages of solution-gel transition process, suggesting the composition of the solutions affected the molecular interactions and then changed the gelling properties. Besides, composite gels that contained the whole egg had higher hardness and lower springiness than those gels that contained egg yolk. The gel hardness after 50% addition of the whole egg and egg yolk was about 561% and 329% of the original gel strength while the gel springiness was 0.91 and 0.94, respectively. From results of microstructure, egg yolk-soybean protein isolate composite gels possessed denser gel network, which may be related with higher solid content of egg yolk. Conversely, the whole egg-soybean protein isolate composite gels showed rigid fiber network with holes, leading to better water mobility, higher hardness and lower springiness.

Effects of dietary fat source on lutein, zeaxanthin and total carotenoids content of the egg yolk in laying hens during the early laying period

ABSTRACT 1. The study was conducted to investigate the effects of different dietary levels of an unsaturated or saturated fat source and the effects of different dietary energy levels in laying hen diets on the carotenoid content of the egg yolk. 2. Seventy-two ISA Brown laying hens aged 22 weeks old were allocated, for a 10 week period, to three treatments: control diet (HE group) with a 3.4% supplemented fat containing 2.1% soybean and 1.3% palm oil as fat sources and a ratio of unsaturated to saturated fatty acid (u/s) of 3.33; a lowered energy diet with 2.4% supplemented fat containing 1.4% soybean and 1.0% palm oil and u/s of 3.41 (LE+high u/s); a lowered energy diet with 2.4% supplemented fat containing 0.5% soybean and 1.9% palm oil and a u/s of 2.39 (LE+low u/s). A marigold plant extract supplement was used as a source of lutein. 3. Performance parameters (feed consumption, feed conversion, body weight), egg production rate and egg quality parameters were similar between treatments. Dietary fat digestibility at the middle of the study period was not different. Egg yolk total fat content was similar in all treatments at the middle and at the end of the study period. 4. Lutein, zeaxanthin, cis-lutein and total carotenoids content were significantly lower in eggs produced from the LE+low u/s group compared to those from the HE and the LE+high u/s groups (P < 0.01 for all parameters). 5. It was concluded that feeding laying hens with a diet containing 1% less supplemented fat and a lower u/s ratio compared to a control diet and to a diet with 1% less supplemented fat with a higher u/s ratio resulted in a significant reduction of carotenoid expression in the egg yolk at the end of experimental period. Performance and egg quality parameters were not affected by treatments.

Dynamics of thymol dietary supplementation in quail (Coturnix japonica): Linking bioavailability, effects on egg yolk total fatty acids and performance traits.

Phytogenic additives such as thymol are encountering growing interest in the poultry industry. However, there are still questions concerning dynamics of their bioavailability, biological action, optimal dosage and duration of supplementation needed to achieve meaningful effects, as well as persistence of induced changes after supplement withdrawal. We studied the link between the dynamics of free thymol concentration and the changes in fatty acids composition in quail egg yolk, both during a month-long chronic dietary supplementation and after 3 weeks of supplement withdrawal (post-supplementation). Fifty, 85 days-old, female quail of homogeneous body weights (251±1g) in egg-laying peak were used. To evaluate potential dose-dependent effects, three increasing doses 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) and two controls were evaluated (n = 10). In parallel, we assessed the concomitant changes in free thymol excretion, potential liver histopathological changes, and birds´ performance traits. Egg yolk and droppings show a dose-dependent increase in THY concentration after 9 days of supplementation and a decrease after post-supplementation. In egg yolk, these changes were accompanied by reduced saturated fatty acid concentrations achieved by 28 days of supplementation in THY2 and 14 days of supplementation in THY4 and THY6. However, after post-supplementation the aforementioned effect disappeared in THY2 but not in THY4 and THY6. While THY2 failed to increase polyunsaturated fatty acids, THY4 and THY6 increased polyunsaturated fatty acids by day 14 of supplementation and remained increased after post-supplementation. Fatty acids changes induced by thymol are consistent with improved nutritional quality of eggs. No treatment effects were observed in liver histopathology and female performance. Findings suggest that both dose of thymol and duration of supplementation modulate thymol and fatty acids concentrations in egg yolk and thymol concentration in droppings. Furthermore, the persistence of those effects after post-supplementation period is also a dose-dependent phenomenon.

Effect of Dietary Incorporation of Linseed Alone or Together with Tomato-Red Pepper Mix on Laying Hens' Egg Yolk Fatty Acids Profile and Health Lipid Indexes.

This study evaluated the effect of linseed incorporation in laying hens’ feed (alone or along with a tomato-red pepper mix) on laying hens’ egg yolk fatty acids profile, as well as on their atherogenic (IA) and thrombogenic (IT) health lipid indexes, and the ratio between the hypocholesterolemic and hypercholesterolemic fatty acids (HH). Sixty 27 weeks-old Novogen White laying hens were divided into three groups and given 100 g/hen/day of a standard diet (Control, C) containing 4.5% of ground linseed (Linseed diet, L), containing 1% of dried tomato paste and 1% sweet red pepper (Lineseeds-Tomato-Pepper, LTP). The linseed dietary inclusion significantly reduced the egg yolk content of palmitic acid from 25.41% (C) to 23.43% (L) and that of stearic acid from 14.75% (C) to 12.52% (L). Feeding 4.5% ground linseed did not affect the egg yolk content of α-Linolenic acid but significantly increased the egg yolk concentration of eicosapentaenoic acid (EPA) from 0.011% (C) to 0.047% (L) and that of docosahexaenoic acid (DHA) from 1.94% (C) to 2.73% (L). The IA and the HH were not affected (p > 0.05) by the dietary addition of linseed, whereas the IT decreased (p < 0.05) from 1.16 (C) to 0.86 (L). Adding tomato-sweet red pepper mix to the linseed-supplemented feed did not affect the measured parameters as compared to the linseed dietary treatment.

Cryopreservation of Swamp Buffalo Semen in Skim Milk Yolk-based Diluent with Two Different Cryoprotectants

The successful of artificial insemination (AI) in buffalo is still low. The quality of frozen semen determines the successful of AI program. Glycerol is widely used for cryopreservation of buffalo semen with unsatisfactory results due to its toxicity and antifertility properties. This study aimed to investigate the effect of glycerol and dimethylformamide (DMF) concentrations in skim milk egg yolk (SMEY)–based diluent on the quality of frozen-thawed swamp buffalo bull semen. Fresh semen was divided into eight aliquots. Each aliquot was diluted in SMEY containing 4%, 5%, 6%, and 7% glycerol and 4%, 5%, 6%, and 7% DMF. Diluted semen was packed into mini straw (0.25 mL), equilibrated at 4 °C for 4 hours, frozen in liquid nitrogen vapor for 10 minutes, and stored at liquid nitrogen container. The straws were thawed after 24 hours at 37 °C for 30 seconds for evaluation. The results showed that the post thawed sperm motility and recovery rate in SMEY extender containing 7% glycerol and 5% DMF were higher than the other glycerol or DMF concentrations. Post thawed sperm viability and plasma membrane integrity in SMEY containing 4%-6% DMF did not differ significantly, however both values were higher than those in 7% DMF. Post thawed sperm viability and plasma membrane integrity did not differ between SMEY containing 6% and 7% glycerol. However, both values were higher than those in 4% and 5% glycerol. It is concluded that 7% glycerol or 5% DMF is considered to be the most suitable cryoprotective agent for swamp buffalo semen cryopreservation.The successful of artificial insemination (AI) in buffalo is still low. The quality of frozen semen determines the successful of AI program. Glycerol is widely used for cryopreservation of buffalo semen with unsatisfactory results due to its toxicity and antifertility properties. This study aimed to investigate the effect of glycerol and dimethylformamide (DMF) concentrations in skim milk egg yolk (SMEY)–based diluent on the quality of frozen-thawed swamp buffalo bull semen. Fresh semen was divided into eight aliquots. Each aliquot was diluted in SMEY containing 4%, 5%, 6%, and 7% glycerol and 4%, 5%, 6%, and 7% DMF. Diluted semen was packed into mini straw (0.25 mL), equilibrated at 4 °C for 4 hours, frozen in liquid nitrogen vapor for 10 minutes, and stored at liquid nitrogen container. The straws were thawed after 24 hours at 37 °C for 30 seconds for evaluation. The results showed that the post thawed sperm motility and recovery rate in SMEY extender containing 7% glycerol and 5% DMF were higher than the other glycerol or DMF concentrations. Post thawed sperm viability and plasma membrane integrity in SMEY containing 4%-6% DMF did not differ significantly, however both values were higher than those in 7% DMF. Post thawed sperm viability and plasma membrane integrity did not differ between SMEY containing 6% and 7% glycerol. However, both values were higher than those in 4% and 5% glycerol. It is concluded that 7% glycerol or 5% DMF is considered to be the most suitable cryoprotective agent for swamp buffalo semen cryopreservation.

Digestibility in the gastrointestinal tract and migration to blood of β′-component (Onk k 5), a major salmon roe IgE-binding protein

The major allergen of chum salmon (Oncorhynchus keta) roe is the β′-component (Onc k 5, β′-c), which is a yolk protein and a fragment of vitellogenin. When yolk content containing β′-c was orally administered to mice, β′-c passed through the gastrointestinal tract and was excreted in feces without marked degradation. The direct administration of β′-c to ligated jejunal and ileal loops showed that β′-c was absorbed through the small intestine and transferred into the blood. Immunohistochemical staining showed that orally administered β′-c was distributed from the apical side to the basal side of intestinal epithelial cells, suggesting that endocytosis may be involved in the intestinal absorption of β′-c. In conclusion, β′-c is absorbed along a large portion of the small intestine and circulates in the blood stream without significant digestion. The resistance of β′-c to gastrointestinal digestion seems to contribute to its strong allergenicity.

Maternal diet deficient in riboflavin induces embryonic death associated with alterations in the hepatic proteome of duck embryos

BackgroundMaternal riboflavin deficiency (RD) induces embryonic death in poultry. The underlying mechanisms, however, remain to be established and an overview of molecular alterations at the protein level is still lacking. We investigated embryonic hepatic proteome changes induced by maternal RD to explain embryonic death.MethodsA total of 80 45-week-old breeding female ducks were divided into two groups of 40 birds each, and all birds were raised individually for 8 weeks. All the female ducks received either a RD or a riboflavin adequate (control, CON) diet, which supplemented the basal diet with 0 or 10 mg riboflavin /kg of diet respectively.ResultsThe riboflavin concentrations of maternal plasma and egg yolk, as well as egg hatchability declined markedly in the RD group compared to those in the CON group after 2 weeks, and declined further over time. The hepatic proteome of E13 viable embryos from 8-week fertile eggs showed that 223 proteins were upregulated and 366 proteins were downregulated (> 1.5-fold change) in the RD group compared to those in the CON group. Pathway analysis showed that differentially expressed proteins were mainly enriched in the fatty acid beta-oxidation, electron transport chain (ETC), and tricarboxylic acid (TCA) cycle. Specifically, all the proteins involved in the fatty acid beta-oxidation and ETC, as well as six out of seven proteins involved in the TCA cycle, were diminished in the RD group, indicating that these processes could be impaired by RD.ConclusionMaternal RD leads to embryonic death of offspring and is associated with impaired energy generation processes, indicated by a number of downregulated proteins involved in the fatty acid beta-oxidation, ETC, and TCA cycle in the hepatic of duck embryos. These findings contribute to our understanding of the mechanisms of liver metabolic disorders due to maternal RD.