Differential polyvalent passive immune protection of egg yolk antibodies (IgY) against live and inactivated Vibrio fluvialis in fish.

Egg yolk antibodies (IgY) can be prepared in large quantities and economically, and have potential value as polyvalent passive vaccines (against multiple bacteria) in aquaculture. This study prepared live and inactivated Vibrio fluvialis IgY and immunized Carassius auratus prior to infection with V. fluvialis and Aeromonas hydrophila. The results showed that the two IgY antibodies hold effective passive protective rates against V. fluvialis and A. hydrophila in C. auratus. Further, the serum of C. auratus recognized the two bacteria in vitro, with a decrease in the bacteria content of the kidney. The phagocytic activity of C. auratus plasma was enhanced, with a decrease in the expression of inflammatory and antioxidant factors. Pathological sections showed that the kidney, spleen, and intestinal tissue structures were intact, and apoptosis and DNA damage decreased in kidney cells. Moreover, the immunoprotection conferred by the live V. fluvialis IgY was higher than that of the inactivated IgY. Addition, live V. fluvialis immunity induced IgY antibodies against outer membrane proteins of V. fluvialis were more than inactivated V. fluvialis immunity. Furthermore, heterologous immune bacteria will not cause infection, so V. fluvialis can be used to immunize chickens to obtain a large amount of IgY antibody. These findings suggest that the passive immunization effect of live bacterial IgY antibody on fish is significantly better than that of inactivated bacterial antibody, and the live V. fluvialis IgY hold potential value as polyvalent passive vaccines in aquaculture.

Nutritional supplement induced modulations in the functional connectivity of a porcine brain.

BACKGROUND: Functional connectivity (FC) measures statistical dependence between cortical brain regions. Studies of FC facilitate understanding of the brain's function and architecture that underpin normal cognition, behavior, and changes associated with various factors (e.g. nutritional supplements) at a large scale. OBJECTIVE: We aimed to identify modifications in FC patterns and targeted brain anatomies in piglets following perinatal intake of different nutritional diets using a graph theory based approach. METHODS: Forty-four piglets from four groups of pregnant sows, who were treated with nutritional supplements, including control diet, docosahexaenoic acid (DHA), egg yolk (EGG), and DHA + EGG, went through resting-state functional magnetic resonance imaging (rs-fMRI). We introduced the use of differential degree test (DDT) to identify differentially connected edges (DCEs). Simulation studies were first conducted to compare the DDT with permutation test, using three network structures at different noise levels. DDT was then applied to rs-fMRI data acquired from piglets. RESULTS: In simulations, the DDT showed a greater accuracy in detecting DCEs when compared with the permutation test. For empirical data, we found that the strength of internodal connectivity is significantly increased for more than 6% of edges in the EGG group and more than 8% of edges in the DHA and DHA + EGG groups, all compared to the control group. Moreover, differential wiring diagrams between group comparisons provided means to pinpoint brain hubs affected by nutritional supplements. CONCLUSION: DDT showed a greater accuracy of detection of DCEs and demonstrated EGG, DHA, and DHA + EGG supplemented diets lead to an improved internodal connectivity in the developing piglet brain.

Effect of autologous platelet-rich plasma on the fertility and quality of cryopreserved buffalo bull semen: a comparative study using OptiXcell® and tris egg yolk extenders.

BACKGROUND: Buffalo spermatozoa have a distinct membrane structure that makes them more vulnerable to cryopreservation, resulting in lower-quality post-thawed sperm. This decreases the success rate of artificial insemination in buffaloes. Understanding and addressing these specific vulnerabilities are essential for improving reproductive techniques in buffalo populations. The properties of cryopreserved buffalo bull semen were examined in this study regarding the impact of adding autologous platelet-rich plasma (PRP) to OptiXcell® or Tris egg yolk-based extenders. Ten buffalo bulls were used to collect semen. Each bull's ejaculate was separated into two main equal amounts, each of which was then diluted with either OptiXcell® or Tris egg yolk-based extender, supplemented with various PRP concentrations (5%, 10%, and 15%), and the control (0%), before being cryopreserved according to established protocols. Following equilibration and thawing, the quality and functionality of the sperm were evaluated, along with the antioxidant enzyme activities (GSH and TAC), malondialdehyde (MDA) content, and in vivo fertilization rate of the thawed semen. RESULTS: All PRP concentrations in both extenders, particularly 10% PRP, improved the quality and functionality of the sperm in both equilibrated and frozen-thawed semen. Additionally, the antioxidant enzyme activities in both extenders were higher in the PRP-supplemented groups compared to the control group in thawed semen (P < 0.05). All post-thaw sperm quality, antioxidant enzyme activities, and functionality aside from DNA integrity were higher (P < 0.05) in the PRP-supplemented OptiXcell® than in the PRP-supplemented Tris egg yolk-based extender. The fertility of cryopreserved semen in the extenders supplemented with 10% and 15% PRP increased (P < 0.05) significantly more than that of the control extenders, with 10% PRP being the optimum concentration in OptiXcell® (80%) compared to that of Tris egg yolk-based extender (66.67%) and control of two extenders (53.33% and 46.67%, respectively). CONCLUSIONS: Even though autologous PRP-supplemented extenders have a protective impact on equilibrated and cryopreserved semen, 10% PRP-supplemented OptiXcell® extenders are more effective at preserving post-thaw semen quality, functionality, and antioxidant capacity, which increases the in vivo fertility of buffalo bulls.

The use of sodium caseinate in the freezing of sheep semen.

The aim of this study was to assess the addition of 2% sodium caseinate in a commercial egg yolk-based medium in frozen ovine semen. Eight Dorper males were used for the study. The ejaculate was divided into two portions and frozen without (G1) or with the addition of 2% sodium caseinate (G2). Kinetic parameters were evaluated using CASA (computer-assisted sperm analysis), and membrane and acrosome integrity as well as oxidative stress were assessed using flow cytometry. After thawing, a thermoresistance test was conducted at time points T0 and T90. For the fertility test, 100 ewes were inseminated with semen from two rams selected based on in vitro parameters, one with good post-thaw quality (+70% total motility) and the other with low post-thaw quality (-55% total motility). For the fertility test, the females were divided into 4 groups for insemination: low-quality ram without caseinate (GBS = 25) and with caseinate (GBC = 25), and high-quality ram without caseinate (GAS = 25) and with caseinate (GAC = 25). Regarding the results of sperm kinetics, there was a statistically significant difference in the parameters of average path velocity (VAP) and curvilinear velocity (VCL) between the group frozen with BotuBov and the group with added caseinate. At time point T90, straight-line velocity maintained a trend (p < .06), with BotuBov® (BB group) being superior to caseinate this time, and in the linearity parameter, caseinate was superior to BotuBov®. Flow cytometry analysis showed no difference between any of the evaluated tests. In the fertility test, there was no statistically significant difference in the pregnancy rate between the BotuBOV® group (23%, 11/48) and the sodium caseinate group (BC group) (33%, 17/52), and no differences were observed in the male versus diluent interaction (p = .70). In conclusion, sodium caseinate supplementation did not influence sperm kinetic parameters and the fertility of sheep.

Effects of different extenders on epigenetic patterns and functional parameters of bull sperm during cryopreservation process.

The cryopreservation process induces alterations in cellular parameters and epigenetic patterns in bull sperm, which can be prevented by adding cryoprotectants in the freezing extenders. The purpose of this study was to compare the protective effects of two extenders based on soybean lecithin (SLE) and egg yolk (EYE) on epigenetic patterns and quality parameters of sperm such as motility parameters, mitochondrial membrane integrity, DNA fragmentation, viability, and apoptotic-like changes of bull sperm after cryopreservation. Results demonstrated that cryopreservation significantly (p < .05) reduced the level of DNA global methylation, H3K9 histone acetylation, and H3K4 histone methylation in both frozen groups compared to the fresh sperm. Also, the level of H3K9 acetylation was lower in the frozen SLE group (21.2 ± 1.86) compared to EYE group (15.2 ± 1.86). In addition, the SLE frozen group had a higher percentage of viability, progressive motility, and linearity (LIN) in SLE frozen group compared to EYE frozen group. However, no difference was observed in mitochondrial membrane integrity and DNA fragmentation between SLE and EYE frozen groups. While soybean-lecithin-based extender showed some initial positive impacts of epigenetics and semen parameters, further investigations can provide useful information for better freezing.

Comparison of the Bactericidal Effect of Ultrasonic and Heat Combined with Ultrasonic Treatments on Egg Liquids and Additional Analysis of Their Effect by NIR Spectral Analysis.

Eggs are a valuable source of nutrients, but they represent a food safety risk due to the presence of microbes. In this work, three types of egg liquids (albumen, yolk and whole egg) previously contaminated with E. coli were treated with ultrasound (US) and a combination of ultrasound and low (55 °C) temperature (US+H). The US treatment parameters were 20 and 40 kHz and 180 and 300 W power and a 30, 45 or 60 min treatment time. The ultrasonic treatment alone resulted in a reduction in the microbial count of less than 1 log CFU, while the US+H treatment resulted in a reduction in CFU counts to below detectable levels in all three egg liquids. Heat treatment and ultrasound treatment had a synergistic effect on E. coli reduction. For all measurements, except for the whole egg samples treated with US, the 20 kHz treated samples showed a significantly (>90% probability level) lower bactericidal effect than the 40 kHz treated samples. PCA and aquaphotometric analysis of NIR spectra showed significant differences between the heat-treated groups' (H and US+H) and the non-heat-treated groups' (US and control) NIR spectra. LDA results show that heat-treated groups are distinguishable from non-heat-treated groups (for albumen 91% and for egg yolk and whole egg 100%).

Effect of salting and dehydration treatments on the physicochemical and gel properties of hen and duck egg yolks, plasma and granules.

BACKGROUND: Salted hen egg yolks are less oily and less flavorful than salted duck egg yolks. However, hen eggs have a more adequate market supply and have a broader application prospect than duck eggs. In the present study, egg yolks, plasma, and granules were dehydrated by adding 1% NaCl to simulate traditional curing process of salted egg yolk. The changes in the pickling process of hen egg yolks (HEY) and duck egg yolks (DEY) plasma and granules were compared to reveal the gelation mechanism and the underlying causes of quality differences in salted HEY and DEY. Salted HEY can be compared with the changes in DEY during the pickling process to provide a theoretical basis for the quality improvement of salted HEY to salted DEY. RESULTS: The results showed that both plasma and granules were involved in gel formation, but exhibited different aggregation behaviors. Based on the intermolecular forces, the HEY proteins achieved aggregation mainly through hydrophobic interactions and DEY proteins mainly through covalent binding. According to spin-spin relaxation time, HEY gels immobilized a large amount of lipid and interacted strongly with lipids. DEY gels showed much free lipid and had weak interaction with lipid. The microstructure showed that HEY proteins were easily unfolded to form a homogeneous three-dimensional gel network structure after salting, whereas heterogeneous aggregates were formed to hinder the gel development in DEY. Changes in protein secondary structure content showed that pickling can promote the transformation of the α-helices to ß-sheets structure in HEY gels, whereas more α-helices structure was formed in DEY gels. CONCLUSION: The present study has demonstrated that different gelation behaviors of hen and duck egg yolk proteins (especially in plasma) through salting treatment led to the difference in the quality of salted HEY and DEY. © 2024 Society of Chemical Industry.

Influence mechanisms of linoleic acid and oleic acid on the gel properties of egg yolk protein.

BACKGROUND: Gel property is among the crucial functional properties of egg yolk (EY), which determines the texture and flavor of EY products. In the present study, the effects of two unsaturated fatty acids [monounsaturated fatty acid oleic acid (OA) and diunsaturated fatty acid linoleic acid (LA)] on the gel properties of EY protein were investigated. RESULTS: Compared with the blank group, the addition of LA and OA (10-50 g kg-1) improved the gel hardness (from 270.54 g to 385.85 g and 414.38 g, respectively) and viscosity coefficient (from 0.015 Pa.sn to 11.892 Pa.sn and 1.812 Pa.sn, respectively). The surface hydrophobicity of EY protein increased to a maximum value of 40 g kg-1 with the addition of both fatty acids (39.06 µg and 41.58 µg, respectively). However, excess unsaturated fatty acids (≥ 50 g kg-1) disrupted the completeness of the gel matrix and weakened the structural properties of the EY gel. CONCLUSION: Both fatty acids improved the gel properties of EY protein. At the same addition level, OA was superior to LA in improving gel properties. The present study provides a theoretical underpinning for the sensible application of unsaturated fatty acids in improving EY gel properties. © 2024 Society of Chemical Industry.

Effects of different extenders, storage temperatures, and antioxidant supplementation on chilled semen quality: a review.

The successful preservation of ram semen is essential to promote genetic variability, ensure semen transportation, and inseminate multiple ewes. Currently, either animal or plant-based lipoprotein-based extenders are used for semen preservation. Animal product-based extenders include milk and egg yolk, while soybean lecithin is a plant-based extender. Although extenders containing products of animal origin better preserve the quality of chilled semen, the in vivo efficacy after 24 h of storage is still of great concern. Storage temperature is another important and effective factor in preserving sperm quality, whereby different storage temperatures are adopted to enhance the storage life of sperm. Low temperatures (4-5 °C) better preserve sperm quality for a longer duration than high temperatures (15, 20, and 25 °C). Moreover, antioxidant supplementation has a positive impact on sperm quality during liquid storage. The current review summarizes the outcomes of various extenders, different storage temperatures, and antioxidant supplementation on the liquid storage of ram sperm.

Use of adjuvant ISA VG 71 to produce neutralizing egg yolk antibodies against bothropic venom.

The use of egg yolk antibodies-IgY technology-represents an alternative to the production of mammalian immunoglobulins and has several advantages regarding animal welfare and lower costs of production. The use of adjuvants to achieve the hyperimmunization of laying hens plays a key role in the success of the production of high levels of the antibodies. In the present work, two different adjuvant systems (Freund's adjuvants and MontanideTM ISA 71 VG) were compared to produce IgY anti-Bothrops alternatus. For the first immunization, formalin-inactivated Salmonella was added to MontanideTM ISA 71 VG to emulate Freund's complete adjuvant which includes a mycobacteria antigen. After eight immunizations, IgY produced by using either adjuvant was able to neutralize the lethal activity of the venom in a mouse model, but differences were found regarding the recognition of components of the venom between the two adjuvants tested. Overall, MontanideTM adjuvant used in this work could be a good alternative choice to produce antibodies capable of neutralizing the lethality of complex antigens. This adjuvant is commercially available and used in the formulation of several poultry vaccines and could be used for the IgY technology instead of traditional immunomodulators such as Freund's adjuvants. Key points • IgY extracts recognized major components of the venom.• Avidity indexes of the IgY extracts increased after the successive immunizations.• IgY obtained by two adjuvant systems neutralized the lethal activity of the venom.

Egg viability and egg mass underlie immune tradeoffs and differences between urban and rural lizard egg yolk physiology.

Urbanization can cause innumerable abiotic and biotic changes that have the potential to influence the ecology, behavior, and physiology of native resident organisms. Relative to their rural conspecifics, urban Side-blotched Lizard (Uta stansburiana) populations in southern Utah have lower survival prospects and maximize reproductive investment via producing larger eggs and larger clutch sizes. While egg size is an important predictor of offspring quality, physiological factors within the egg yolk are reflective of the maternal environment and can alter offspring traits, especially during energetically costly processes, such as reproduction or immunity. Therefore, maternal effects may represent an adaptive mechanism by which urban-dwelling species can persist within a variable landscape. In this study, we assess urban and rural differences in egg yolk bacterial killing ability (BKA), corticosterone (CORT), oxidative status (d-ROMs), and energy metabolites (free glycerol and triglycerides), and their association with female immune status and egg quality. Within a laboratory setting, we immune challenged urban lizards via lipopolysaccharide injection (LPS) to test whether physiological changes associated with immune system activity impacted egg yolk investment. We found urban females had higher mite loads than rural females, however mite burden was related to yolk BKA in rural eggs, but not urban eggs. While yolk BKA differed between urban and rural sites, egg mass and egg viability (fertilized vs. unfertilized) were strong predictors of yolk physiology and may imply tradeoffs exist between maintenance and reproduction. LPS treatment caused a decrease in egg yolk d-ROMs relative to the control treatments, supporting results from previous research. Finally, urban lizards laid a higher proportion of unfertilized eggs, which differed in egg yolk BKA, CORT, and triglycerides in comparison to fertilized eggs. Because rural lizards laid only viable eggs during this study, these results suggest that reduced egg viability is a potential cost of living in an urban environment. Furthermore, these results help us better understand potential downstream impacts of urbanization on offspring survival, fitness, and overall population health.

Urbanization and maternal hormone transfer: Endocrine and morphological phenotypes across ontogenetic stages.

The phenotypes observed in urban and rural environments are often distinct; however, it remains unclear how these novel urban phenotypes arise. Hormone-mediated maternal effects likely play a key role in shaping developmental trajectories of offspring in different environments. Thus, we measured corticosterone (Cort) and testosterone (T) concentrations in eggs across the laying sequence in addition to Cort concentrations in nestling and adult female house wrens (Troglodytes aedon) at one urban and one rural site. We found that egg T concentrations were not different between birds from urban and rural sites. However, across all life stages (egg, nestling, and adult female), Cort concentrations were higher at the urban site. Additionally, urban nestling Cort concentrations, but not rural, correlated with fine-scale urban density scores. Furthermore, rural egg volume increased over the laying sequence, but urban egg volume leveled off mid-sequence, suggesting either that urban mothers are resource limited or that they are employing a different brood development strategy than rural mothers. Our study is one of the first to show that egg hormone concentrations differ in an urban environment with differences persisting in chick development and adult life stages. We suggest that maternal endocrine programing may shape offspring phenotypes in urban environments and are an overlooked yet important aspect underlying mechanisms of urban evolution.

Effects of egg yolk choline intake on cognitive functions and plasma choline levels in healthy middle-aged and older Japanese: a randomized double-blinded placebo-controlled parallel-group study.

BACKGROUND: Choline, as a neurotransmitter acetylcholine precursor, is reportedly associated with cognitive function. Although there are several cohort and animal studies on choline-containing foods and cognitive function, only a few interventional studies were reported. Egg yolk is a rich source of different choline-containing chemical forms, such as phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and α-glycerophosphocholine (α-GPC). This study aimed to investigate the effect of consuming 300 mg of egg yolk choline per day on cognitive function of Japanese adults. METHODS: A 12-week, randomized, double-blind, placebo-controlled, parallel-group study was conducted in 41 middle-aged and elderly males and females (43.9% female) aged ≥ 60 years and ≤ 80 years without dementia. Participants were randomly assigned to placebo and choline groups. The choline group received a supplement containing egg yolk choline (300 mg/day), and the placebo group received an egg yolk supplement free from choline for 12 weeks. Assessments of Cognitrax, Trail Making Tests (TMT) part A and B, the MOS 36-Item Short-Form Health Survey (SF-36), the Simplified Japanese Version of the WHO-Five Well-Being Index (WHO-5), and plasma choline levels were performed before and 6 and 12 weeks after supplement intake. In the present study, 19 subjects (9 in the placebo group and 10 in the choline group) were excluded due to the violation of the discontinuation criteria or participant compliance, and 41 subjects were analyzed. RESULTS: The change amount of verbal memory scores and verbal memory test-correct hit (delay) was significantly higher in the choline group than in the placebo group at baseline-6 and baseline-12 weeks. The plasma free choline level was significantly higher in the choline group compared with the placebo group at 6 weeks. Conversely, the choline group showed significantly lower Cognitrax processing speed scores, symbol digit coding testing correct responses, and SF-36 physical quality of life summary scores compared to the placebo group at 6 weeks. CONCLUSIONS: The results suggested that continued 300 mg/day intake of egg yolk choline improved verbal memory, which is a part of cognitive functions. To confirm the observed effects of egg yolk choline, more well-designed and large-scale studies are warranted. TRIAL REGISTRATION: Study protocols were pre-registered in the Clinical Trials Registration System (UMIN-CTR) (UMIN 000045050).

Total mercury in different egg tissues provides insights to mercury metabolisms in bird bodies.

Mercury (Hg) pollution in birds has been widely reported, but the metabolism of Hg in bird bodies remains unclear. Measurement of Hg concentrations in bird tissues (muscles and organs) could provide insights into the metabolism of Hg in bird bodies, however, this approach is often invasive. To avoid invasive procedures, we conducted feeding experiments using chickens and used eggs as a proxy for understanding Hg metabolism in chicken bodies. For the control group, various THg concentrations were observed in egg whites, egg yolks, and eggshells, but the THg concentration trends for different egg tissues were not statistically different (P > 0.05). For the Hg feeding group (0.3 mg/kg body weight, feeding once), Hg peaks were observed in egg yolks and egg whites at different time periods, suggesting different response time to dietary Hg in chicken body tissues. Mercury in egg yolks peaked at Day 6, suggesting their quick response to dietary Hg. Egg whites reached Hg peak at Day 20, exhibiting a slower response to dietary Hg. Eggshells did not show a Hg peak, perhaps due to their predominant inorganic components that do not trigger Hg bioaccumulation. We measured THgyolk/THgwhite ratios in various chicken eggs purchased from three areas in Guizhou, SW China. The THgyolk/THgwhite ratios for Huaxi, Hezhang and Wuchuan were 1.33 (0.57-2.41), 7.89 (4.27-19.47) and 2.64 (1.68-4.22), respectively, to suggest different exposure history for chickens. This study provides new insights into the metabolism and lifetime of Hg in bird bodies.

Effects of extender filtration and egg yolk concentration on canine semen cryopreservation.

The semen cooling and freezing extenders commonly contain the chicken egg yolk (EY) as the main sperm cryoprotectant. Besides its advantages, the EY has large lipoprotein granules that cause several physical and biological interferences. The previous studies have proposed several methods to resolve the problems with the EY-based semen extenders, including mechanical agitation, EY fractionation, replacing the EY with purified EY LDL, and ultrasonication. In the current research, we aimed to evaluate the syringe filtration (220 nm) of an EY-based canine semen freezing extender as a simple and cheap method to remove the EY granules. We also studied the possibility of re-aggregation of EY granules after cooling, freeze/thawing, and lyophilization/rehydration of the filtered extenders. Additionally, we compared the effects of the filtration on lipid profile, turbidity, EY particle size distribution, and osmolality of the EY-based extenders. Next, we examined the effects of filtered extenders containing different levels of EY (5%, 10%, 15%, 20%, and 25%) versus the control extender (20% EY, unfiltered) on post-thaw sperm quality traits. We collected the semen samples from seven clinically healthy mixed-breed adult dogs and pooled them for sperm freezing procedures. Samplings were repeated at least five times, independently. Our results indicated that the syringe filtration could remove the large EY particles and reduce the extender turbidity without affecting the lipid profile of the whole extender solution. The filtered extender supplemented with 25% (v/v) EY led to the best post-thaw canine spermatozoa quality markers. The frozen-thawed spermatozoa evaluations included motility parameters (computer-assisted semen analysis system), membrane and acrosome integrity (hypo-osmotic swelling test, chlortetracycline binding assay), DNA fragmentation (sperm chromatin dispersion assay), membrane lipid peroxidation (MDA levels), apoptosis (Annexin V/propidium iodide assay), and fertility-associated sperm mRNA transcript abundance (protamine 2 and 3). In conclusion, the syringe filtration of the EY-based semen extenders was a simple and cheap method that could effectively remove large EY lipoprotein granules and possibly prevent EY-origin bacterial contamination of the final extender solution. The EY at 25% (v/v) concentration in the filtered extenders resulted in the highest canine spermatozoa cryo-tolerance.

Short-term preservation of canine sperm-binding ability and other metrics using the INRA-96 in comparison to Tris-egg yolk extender.

The use of assisted reproductive techniques, such as chilled semen, contributes to the maintenance and genetic improvement of canine breeding. The INRA-96 extender is a commercially available, chemically defined medium that was initially developed for the preservation of equine semen and exhibits preservation potential in the canine species. This research aims to evaluate the INRA-96 extender as an alternative for the short-term preservation of canine semen in terms of sperm quality parameters such as motility and kinetic parameters, integrity and functionality of the plasma membrane in fresh and chilled-rewarmed samples, as well as the sperm-binding ability using the perivitelline membrane of the chicken egg as an indicator of the fertilizing capacity of the preserved semen. A total of 18 ejaculates from 9 French bulldogs (two ejaculates per dog) were collected and divided into two aliquots that were diluted in Tris-egg yolk 20% (control) or INRA-96 to a final concentration of 100 × 106 sperm/mL. Samples were refrigerated in a biological incubator at 5°C and evaluated at 0, 24 and 48 h time points. Comparing the two treatments after 48 h of refrigeration, both extenders showed similar values (p < .5) for the majority of kinetic parameters, with the INRA-96 group promoting a total motility of 88.1 ± 2.9%. In addition, the morphology, integrity and functionality of the plasma membrane were preserved above 70% in this group. Dilution with INRA-96 also provided a significantly higher amount of sperm bound (256.2 ± 21.1) to the perivitelline membrane of the egg yolk compared to the sperm-binding rates (p < .05) achieved at the use of Tris-egg yolk (215.2 ± 21 bound spermatozoa) at 48 h. Our study proved similar functional properties of dog sperm cells treated with INRA-96 in comparison to commonly used home-made Tris-based extender during short-time storage.

Effect of freeze-dried quail egg white and yolk addition to semen extender on viability of rooster sperm stored for 6 h at 4°C.

The effect of freeze-dried quail egg white and yolk addition to basic EK extender on morphology and motility of chicken broiler breeder semen was investigated. Fresh pooled semen was divided into eight parts: fresh, undiluted (control), diluted in 1:2 ratio (v/v) with basic EK extender, EK + 200 mg/ml of egg white, EK + 100 mg/ml of egg white, EK + 50 mg/ml of egg white, EK + 100 mg/ml of egg yolk, EK + 50 mg/ml of egg yolk, EK + 25 mg/ml of egg yolk. Semen samples were evaluated 15 min after dilution and after 6 h of storage at 4°C. In the fresh semen, the number of live normal sperm was the highest in semen diluted with EK + 200 mg of egg white and EK + 100 mg of egg yolk, while the highest sperm motility was in the neat semen. Semen storage reduced the number of normal sperm in all analysed semen samples. In the neat semen, the number of normal sperm decreased, in relation to the fresh not-stored samples, by 36.8% (from 72.3% to 35.5%), with EK extender by 9.2%, in samples enriched with egg white, from 8.4% (EK + 200 mg) to 10.0% (EK + 100 mg), and in EK with egg yolk addition, from 1.2% (EK + 50 mg) to 10.6% (EK + 100 mg). The highest percentage of motile sperm was observed in EK extender enriched with 50 mg of egg white (77.1%) and EK + 25 mg of egg yolk (65.3%).

Fertility results after exocervical insemination using goat semen cryopreserved with extenders based on egg yolk, skim milk, or soybean lecithin.

To evaluate the effects of four extenders on the post-thaw quality and fertility of goat semen, six Yunshang Black bucks' semen was collected, pooled, diluted with Andromed® (Andr®), Optidyl® (Opt®), P3644 Sigma l-phosphatidylcholine (l-α SL), and skim milk-based (Milk) extenders, and then cryopreserved. The sperm motilities, abnormalities, membrane and acrosome integrity, mitochondrial activity, apoptosis, and reactive oxygen species (ROS) production were evaluated after thawing. After exocervical insemination with the thawed semen, the pregnancy, lambing, and twinning rates were recorded and compared. The results showed that sperm motilities, membrane integrity, acrosome integrity, mitochondrial activity, and viable spermatozoa were significantly higher in the Andr® and Opt® groups than those in the l-α SL and Milk groups (p < .05). Furthermore, there was no difference between Andr® and Opt® (p > .05). The sperm abnormality was lower in semen frozen with the Andr® or Opt® extenders, as compared to the l-α SL or Milk extender (p < .05). Regarding, the viable cells with low ROS production, the optimal results were obtained in the semen frozen with Andr® and Opt® extenders. Following exocervical insemination, the pregnancy and lambing rates in the Milk group were significantly lower than those in the other groups (p < .05). No difference was found in the pregnancy and lambing rates between Andr®, Opt®, and l-α SL (p > .05). Furthermore, the twinning rates were similar between these four groups (p > .05). In conclusion, egg yolk or skim milk can be substituted by soybean lecithin during cryopreservation of goat semen.

Quantitative Lipidome Analysis of Boiled Chicken Egg Yolk under Different Heating Intensities.

The effects of the four heating intensities (hot-spring egg yolk, HEY; soft-boiled egg yolk, SEY; normal-boiled egg yolk, NEY; and over-boiled egg yolk, OEY) on lipidomes of boiled egg yolks were investigated. The results indicated that four heating intensities had no significant effect on the total abundance of lipids and lipid categories except for bile acids, lysophosphatidylinositol, and lysophosphatidylcholine. However, of all the 767 lipids quantified, the differential abundance of 190 lipids was screened among the egg yolk samples at four heating intensities. Soft-boiling and over-boiling altered the assembly structure of the lipoproteins through thermal denaturation and affected the binding of lipids and apoproteins, resulting in an increase in low-to-medium-abundance triglycerides. The decreased phospholipid and increased lysophospholipid and free fatty acid in HEY and SEY suggests potential hydrolysis of phospholipids under relatively low-intensity heating. Results provide new insights into the effect of heating on the lipid profiles of egg yolk and would support the public's choice of cooking method for egg yolks.

Antioxidant Activity of Egg Yolk Protein Hydrolysates Obtained by Enzymatic and Sub-Critical Water Hydrolysis.

Obtaining peptides with antioxidant properties by enzymatic hydrolysis has been widely described; however, the use of non-enzymatic methods to obtain peptides with antioxidant capacities has been poorly investigated. In this study, non-soluble proteins obtained from delipidated egg yolk granules were hydrolyzed with trypsin, and with a non-enzymatic method using sub-critical water hydrolysis under a non-oxidizing (nitrogen) and oxidizing (oxygen) atmosphere. The effect of the sub-critical water hydrolysis on the amino acids' composition of the hydrolysates was assessed. Furthermore, the antioxidant capacities of the hydrolysates were evaluated using the ABTS•+ scavenging assay, the DPPH radical scavenging activity assay, and by measuring the reducing power of the peptides, the peptides' ferrous ion chelating capacities, and the antioxidant effect of the peptides on beef homogenates. The hydrolysate obtained by sub-critical water hydrolysis under a nitrogen stream showed similar or better results in the antioxidant tests than those obtained using trypsin hydrolysis, except in the ferrous chelating capacity, where the trypsin hydrolysate showed the best performance. The oxidizing environment promoted by the oxygen in the other sub-critical water hydrolysis method tested produced the peptides with the lowest antioxidant capacities, due to changes in the primary structure of the peptides. These results suggest that the sub-critical water hydrolysis method under a nitrogen stream, in comparison with the enzymatic hydrolysis, is a reliable method to obtain peptides with good antioxidant capacities.