Differences In Egg Research Articles

Nutritional differences in eggs, chicken, and plantain from agroecological, conventional, and commercial systems: a case study in Valle del Cauca, Colombia

ABSTRACT This case study examines the nutritional differences between agroecological, conventional, and commercial products in Valle del Cauca, Colombia. Using a participatory methodology with local farmers, eggs, chicken, and plantain were selected for analysis. Moisture, protein, fat, ash, phosphorus, potassium, calcium, and magnesium contents were compared across the three production systems. Statistical analyses included ANOVA and MANOVA. Results indicate that agroecological products from the studied farms tended to have lower moisture content. Agroecological eggs showed higher fat content (11.09 g/100 g vs 9.32 g/100 g conventional and 8.45 g/100 g commercial). Agroecological chicken presented higher protein content (22.37 g/100 g vs 20.73 g/100 g conventional and 18.1 g/100 g commercial) and potassium (281 mg/100 g vs 298 mg/100 g conventional and 213 mg/100 g commercial). Agroecological plantain had higher ash content (0.85 g/100 g vs 0.77 g/100 g conventional and 0.79 g/100 g commercial) and calcium (8 mg/100 g vs 5 mg/100 g conventional and 6 mg/100 g commercial). These differences were statistically significant (p < 0.05). While these findings suggest potential nutritional benefits of agroecological production in this region, further studies with a larger number of replicates are needed to confirm these trends on a broader scale.

In Vitro and In Vivo Genotoxicity of Polystyrene Microplastics: Evaluation of a Possible Synergistic Action with Bisphenol A.

The ubiquitous presence of plastics represents a global threat for all ecosystems and human health. In this study, we evaluated, in vitro and in vivo, the genotoxic potential of different concentrations of polystyrene microplastics (PS-MPs) and their possible synergistic interactions with bisphenol-A (BPA). For the in vitro and the in vivo assays, we used human lymphocytes and hemocytes from Lymnaea stagnalis, respectively. The genomic damage was evaluated by the micronucleus assay, and differences in eggs laid and growth of L. stagnalis were also evaluated. In human lymphocytes, PS-MPs alone at the concentration of 200 μg/mL and in association with BPA 0.100 µg/mL significantly increased the frequencies of micronuclei and nuclear buds, indicating a possible in vitro genotoxic additive action of these two compounds. Vice versa, PS-MPs did not result in genotoxicity in hemocytes. Our results indicated that PS-MPs have genotoxic properties only in vitro and at a concentration of 200 µg/mL; moreover, this compound could intensify the genomic damage when tested with BPA, indicating possible cumulative effects. Finally, PS significantly reduced the growth and the number of laid eggs in L. stagnalis.

Host Preference of &lt;i&gt;Xanthopimpla&lt;/i&gt; Saussure Parasitising &lt;i&gt;Sesamia inferens&lt;/i&gt; Walker

Host selection sequence of two parasitoids of under the genus Xanthopimpla Saussure viz., Xanthopimpla flavolineata (Xf) Cameron [Xf] and X. stemmator (Thunberg) (Xs) and suitability of various pupal stages of Sesamia inferens as a factitious host for rearing was investigated. There was no significant difference in egg laying between the single and repeated attempts by both Xf and Xs. The probing time of Xf and Xs in the rice stem with concealed host (2.26± 0.10 and 1.60± 0.13 min) and a hollow stem without a host was found to be 1.19± 0.14 and 0.59± 0.15 min, respectively. However, Xs did not parasitize the naked pupa. The number of ovipositor insertions was 1.50± 0.17 in concealed pupae and 0.92± 0.15 in hollow stem without host. Among the stages of S. inferens pupae tested for acceptance by Xf and Xs, the prepupa was preferred the most followed by one- and two-day-old pupa, while five- and six-day-old pupae were not preferred.

A double ovulation protocol for Xenopus laevis produces doubled fertilisation yield and moderately transiently elevated corticosterone levels without loss of egg quality.

The African claw-toed frog, Xenopus laevis, is a well-established laboratory model for the biology of vertebrate oogenesis, fertilisation, and development at embryonic, larval, and metamorphic stages. For ovulation, X. laevis females are usually injected with chorionic gonadotropin, whereupon they lay typically hundreds to thousands of eggs in a day. After being rested for a minimum of three months, animals are re-used. The literature suggests that adult females can lay much larger numbers of eggs in a short period. Here, we compared the standard "single ovulation" protocol with a "double ovulation" protocol, in which females were ovulated, then re-ovulated after seven days and then rested for three months before re-use. We quantified egg number, fertilisation rate (development to cleavage stage), and corticosterone secretion rate as a measure of stress response for the two protocol groups over seven 3-month cycles. We found no differences in egg number-per-ovulation or egg quality between the groups and no long-term changes in any measures over the 21-month trial period. Corticosterone secretion was elevated by ovulation, similarly for the single ovulation as for the first ovulation in the double-ovulation protocol, but more highly for the second ovulation (to a level comparable to that seen following shipment) in the latter. However, both groups exhibited the same baseline secretion rates by the time of the subsequent cycle. Double ovulation is thus transiently more stressful/demanding than single ovulation but within the levels routinely experienced by laboratory X. laevis. Noting that "stress hormone" corticosterone/cortisol secretion is linked to physiological processes, such as ovulation, that are not necessarily harmful to the individual, we suggest that the benefits of a doubling in egg yield-per-cycle per animal without loss of egg quality or signs of acute or long-term harm may outweigh the relatively modest and transient corticosterone elevation we observed. The double ovulation protocol therefore represents a potential new standard practice for promoting the "3Rs" (animal use reduction, refinement and replacement) mission for Xenopus research.

The Effects of Lithium Chloride Exposure on the Reproduction of Caenorhabditis elegans.

Caenorhabditis elegans ( C. elegans) are model organisms that share similar anatomical structures to humans. By exploring the effects of lithium chloride (LiCl) on C. elegans, we can collect crucial data regarding the compound's impact on patients taking psychiatric medications containing LiCl. Here we performed an egg retention assay on nematode populations to explore how LiCl can influence reproduction. We found a statistically significant difference in eggs retained between control and experimental groups, suggesting that LiCl has negative effects on reproductive health.

Diet–egg relationships and equilibration of fatty acids in eggs of southern flounder, Paralichthys lethostigma

There is increasing interest in the transfer of nutrients from broodstock diets to eggs due to the consequences for egg and larval quality. Analyses were conducted with southern flounder Paralichthys lethostigma to identify which fatty acids (FAs) in eggs are influenced by broodstock diet and how long it takes for the FA composition of eggs to equilibrate to the broodstock diet. Data were obtained from a laboratory experiment and from hatchery production operations. For each source, two populations of adult flounder were given one or the other of two diet treatments. In the laboratory experiment, the diets differed markedly in FA composition. In the hatchery, a base diet was supplemented on two different schedules. Each of the four diet treatments produced eggs with significantly different mean FA compositions. Of the 27 FAs measured, 19 differed significantly between diets and had corresponding significant differences in eggs (direct diet–egg relationships). Combining results with data from a prior study showed that equilibration of eggs to a change in adult diet takes 8–16 weeks for southern flounder. These findings will be useful for improving broodstock diets and feeding protocols for captive flounder being used by stock-enhancement programs that are designed to mitigate the long-term and widespread population declines of this species.

Maternal patterns of inheritance alter transcript expression in eggs

BackgroundModifications to early development can lead to evolutionary diversification. The early stages of development are under maternal control, as mothers produce eggs loaded with nutrients, proteins and mRNAs that direct early embryogenesis. Maternally provided mRNAs are the only expressed genes in initial stages of development and are tightly regulated. Differences in maternal mRNA provisioning could lead to phenotypic changes in embryogenesis and ultimately evolutionary changes in development. However, the extent that maternal mRNA expression in eggs can vary is unknown for most developmental models. Here, we use a species with dimorphic development— where females make eggs and larvae of different sizes and life-history modes—to investigate the extent of variation in maternal mRNA provisioning to the egg.ResultsWe find that there is significant variation in gene expression across eggs of different development modes, and that there are both qualitative and quantitative differences in mRNA expression. We separate parental effects from allelic effects, and find that both mechanisms contribute to mRNA expression differences. We also find that offspring of intraspecific crosses differentially provision their eggs based on the parental cross direction (a parental effect), which has not been previously demonstrated in reproductive traits like oogenesis.ConclusionWe find that maternally controlled initiation of development is functionally distinct between eggs of different sizes and maternal genotypes. Both allele-specific effects and parent-of-origin effects contribute to gene expression differences in eggs. The latter indicates an intergenerational effect where a parent’s genotype can affect gene expression in an egg made by the next generation.

Evaluation of Resistance of Eleven Maize Races (Zea mays L.) to the Red Spider Mite (Tetranychus merganser, Boudreaux).

At least 59 maize races (Zea mays L.) have been registered in Mexico. The feeding damage caused by insects and mites to maize crops generates up to ~30% of maize yield losses. Spider-mite-resistant plants are needed. The red spider mite, Tetranychus merganser Boudreaux (Acari: Tetranychidae), is distributed in the United States, China, Mexico, and Thailand. It is considered a potential pest in Mexican agriculture. The aim of this study was to evaluate the resistance mechanisms (antixenosis and antibiosis) of 11 native maize populations, representative of each race of maize grown in Tamaulipas, Mexico, to T. merganser under laboratory conditions. The aim was also to obtain information on the chemical composition and some morphological characteristics of these maize races and to identify resistant maize races for incorporation into a breeding program. Antixenosis was assessed by non-preference for oviposition and feeding. Antibiosis was measured by growth rate (ri). The presence of secondary metabolites in the 11 maize races were different. In the 11 maize races, quantitative analysis of total phenol concentration, total flavonoid concentration, and antioxidant capacity were significantly different. The multivariate analysis of variance showed that there is evidence of antixenosis noted by maize race differences in egg laying and percentage feeding damage but not of antibiosis noted by growth rate. Red spider mites laid significantly more eggs on the Celaya (24 h: 25.67 ± 17.04, 48 h: 42.67 ± 26.86, 72 h: 49.33 ± 28.54) race than on Raton (24 h: 7.00 ± 5.00, 48 h: 12.67 ± 8.02, 72 h: 14.67 ± 9.29) and Elotes Occidentales × Tuxpeño (24 h: 9.67 ± 5.85, 48 h: 15.33 ± 10.69, 72 h: 17.67 ± 10.97) races. However, the growth rate and mortality of T. merganser in the 11 corn races were similar. The Vandeño (24 h: 11.67 ± 2.89, 48 h: 27.67 ± 7.64, 72 h: 30.00 ± 18.03) and Tabloncillo × Tuxpeño (24 h: 18.33 ± 7.64, 48 h: 25.00 ± 8.66, 72 h: 25.00 ± 8.66) races were the most resistant to red spider mite damage, whereas the most susceptible race was Celaya (24 h: 26.67 ± 15.28, 48 h: 48.33 ± 29.30, 72 h: 65.00 ± 30.00). Further analysis by PCA at 24, 48, and 72 h found the Celaya race positively correlated to growth rate and oviposition of T. merganser and to a lesser extent with the percentage of feeding damage, suggesting that the Celaya race was most susceptible to T. merganser. At 24 h, the Vandeño race was most resistant, given a negative correlation to growth rate and oviposition by T. merganser. The PCA at 48 and 72 h noted the Elotes Occidentales × Tuxpeño race was most resistant to red spider mite, with negative relationships to growth rate and oviposition and, to a lesser extent, to feeding damage. This resistance is due to the differences in both its morphological characteristics and the secondary metabolites present in their leaves.

Egg fatty acid profiles and potential health risk from defatted insect meal in laying hens’ diets

Insects, a staple feed for wild birds and free ranging poultry, have a relatively high protein quality and are a promising feed for commercial poultry. Replacing soybean meal with insect derived feeds potentially reduces dependency on feed imports, increasing the sustainability of egg production – but only if maintaining or enhancing their nutritional quality. This study investigated egg fatty acid (FA) profiles from replacing soyabean meal with Hermetia illucens (black soldier fly) meal (HIM) for laying hens. A three-week trial with 30 organic Lohman Selected Leghorn hens between 64-74 weeks old was repeated with four flocks at the end of their first laying cycle. In all replicate trials, ten birds were randomly allocated to each of three diets: (1) control with 360 g soybean/kg and no HIM; (2) H12 with 120 g HIM and 156 g soybean/kg; and (3) H24 with 240 g HIM/kg and no soybean. Complete replacement of soya (H24) increased saturated fatty acid (SFA) and monounsaturated fatty acids (MUFA) and decreased total polyunsaturated fatty acids (PUFA), omega-6 (n-6) and omega-3 (n-3) PUFA concentrations in eggs. The intermediate H12 diet (replacing 33% soya) gave similar n-3 and MUFA concentrations to control eggs but significantly increased SFA and reduced total PUFA. However, birds moderated the transfer of high intakes of potentially damaging C12:0 and C14:0 into eggs and although differences in eggs were highly significant and great (relative to very low levels in control eggs) concentrations were substantially lower than in insect meal itself and some commonly consumed foods.

Importance of a turbulent river section below a giant waterfall for fish spawning: Indications from drift and dispersion patterns of early life stages

AbstractSeasonal drift patterns of fish eggs and larvae were analysed along the river section downstream the Iguaçu River Falls to the confluence with Paraná River, over three spawning seasons. This river section is situated in a narrow rocky canyon characterized by a steep slope, which leads to highly turbulent and fast flowing conditions in a series of rapids. Water transit time in this river stretch of 20 km was short (5–11 h), the flow‐velocity in rapids can reach values of more than 6 m s−1. Densities of drifting eggs and larvae varied between three spawning seasons, and differences of eggs were more pronounced compared to larvae. Eggs and larvae were observed all along the river section. A spatial, longitudinal distribution pattern of larvae was found, with higher numbers in the upper section. A distinct spatial sequence of different embryonic stages was observed, with the highest abundance of early stages. Larval densities were low in comparison to egg densities, and preflexion and flexion stages predominated. High abundance of buoyant eggs in drift indicates fish spawning in rapid and turbulent waters of the Iguaçu River, particularly downstream from the Iguaçu Falls. Rainfall and turbidity may be the main trigger for spawning. Spawned eggs drifted quickly towards the confluence, most are likely to hatch in the Paraná River, while larvae disperse to nursery habitats even in the river section below the falls. Thus, inshore zones along the whole stretch provide nursery habitats for larval development of fish species exhibiting different reproductive strategies.

The Impact of Effective Microorganisms (EM) on Egg Quality and Laying Performance of Chickens.

Chickens kept under modern production system are very small and contribute less than 2% of eggs and meat production in Ethiopia. In some parts of the country, effective microorganism (EM) has been used as a means of improving egg and meat production. However, there is information gap on the use and effect of EM on egg quality and laying performance of chickens in the local context. This study was conducted in Aksum University's poultry farm located at the main campus in Axum, to evaluate egg laying performance and quality of eggs in layer chickens treated with effective microorganisms in feed and water. In this experiment, 180 pullets of ISA Brown chickens with uniform age and weight were used and managed in a cage system. Chickens were subjected to 4 treatments with 3 replications, and each replication consisted of 15 chickens. Data collection was started at the first egg lay. Data including feed intake, conversion ratio, and age at first laying, laying percentage, and egg quality parameters were collected. Statistical analysis was carried out using JMP. Chickens fed with EM in feed and drinking water had higher egg production percentage. There was a significant difference in egg laying percentage between the treated and control groups (P < 0.001). Eggs from chickens given EM in feed and water were 6% heavier in weight than those from control birds. Lower feed daily intake (115.5 gram) and feed conversion rate (2.05) were achieved in chickens treated with EM in feed and water. Significant improvement on egg quality was revealed in chickens that received EM in feed and water. From this experiment, it can be concluded that the use of EM in feed and water improves egg production in layer chickens and therefore recommended for medium-scale poultry farms in Northern Ethiopia.

Diploid and aneuploid sperm in tetraploid ginbuna, Carassius auratus langsdorfii

Ginbuna (Carassius auratus langsdorfii (Teleostei: Cyprinidae)) occur in diploid, triploid, and tetraploid forms in wild populations. Diploid females reproduce bisexually, whereas polyploid (triploid and tetraploid) females reproduce gynogenetically with no contribution from sperm nuclei. However, tetraploid males produce diploid sperm. The mechanism responsible for the differences in egg and sperm ploidy has not been elucidated as tetraploid males are rare in wild populations. Here, we aimed to characterize the types of sperm and elucidate the mechanism of spermatogenesis in ginbuna. In the present study, we artificially produced tetraploid males by crossbreeding triploid ginbuna females with diploid goldfish (Carassius auratusauratus) males via accidental incorporation of sperm nuclei. We then examined spermatogenesis to reveal the process by which reduced diploid sperm are generated from tetraploid germ cells. DNA fingerprinting by random amplified polymorphic DNA (RAPD)-PCR indicated that the tetraploid progeny had a paternally derived genome. For the tetraploid male sperm, there were narrow (N-type) and broad (B-type) flow cytometrical histograms. The N-type were determined to be diploid with a low coefficient of variation (CV) by flow cytometry. The B-type were found to be aneuploid (hypodiploid to hexaploid) with a high CV. The head sizes of B-type sperm were variable, whereas those of the N-type sperm were uniform. Computer-assisted sperm analysis (CASA) revealed that both the haploid and diploid B-type sperm were weakly motile compared with the haploid sperm of goldfish and the diploid N-type sperm of tetraploid males. Bivalents and various multivalents were observed in the meiotic configurations of diploid spermatogenesis. In aneuploid spermatogenesis, most of the chromosomes were unpaired univalents and there were very few bivalents. Our findings provide empirical evidence for two different types of spermatogenesis in tetraploid C. a. langsdorfii males. Meiotic synapses might explain the observed differences in the ploidy status of the two sperm types.

Detection and analysis of serum food-specific IgG antibody in Beijing area

Objective: The level of food specific IgG antibody in serum of patients with suspected food intolerance in Beijing area was detected and analyzed, so as to provide a basis for patients to eliminate the food that causes disease in their diet. Methods: Data were retrospectively analyzed in a total of 2368 suspected chronic food intolerance patients (all resident population in Beijing) admitted to Beijing Jishuitan Hospital from October 2015 to December 2019, including 859 males and 1509 females. The age range ranged from 2 months to 90 years, (40.2±18.6) years, and the median age was 36 years. Serum specific IgG (sIgG) antibody concentrations in 14 kinds of food (beef, chicken, pork, cod, shrimp, crab, egg, milk, corn, wheat, mushroom, soybean, tomato and rice) were determined by enzym-linked immunosorbentassay (ELISA).SPSS V22.0 was used for statistical analysis, and χ2 was used to compare the positive rate of each group. Results: The positive rate of food sIgG in 2 368 patients was 82.7% (1959/2368), the higher sIgG positive rates were found in eggs (54.7%), shrimp (29.0%) and milk (26.0%), and the lowest sIgG positive rates were found in pork (4.1%) and beef (1.2%) (P<0.05).There was significant gender difference in egg (χ²=10.885) and shrimp (χ²=6.607) sIgG, and female was significantly higher than male (P<0.05).The sIgG positive rates of egg (χ²=515.645), shrimp (χ²=74.20.4), milk (χ²=305.65), soybean (χ²=39.413), wheat (χ²=133.222), cod (χ²=25.540), crab (χ²=55.521), corn (χ²=20.645), tomato (χ²=118.108), chicken (χ²=32.821), pork (χ²=26.539), beef (χ²=21.632) and rice (χ²=25.335) were significant in different age groups. The positive rate of shrimp and crab sIgG increased with age (P<0.05).The positive rate of tomato sIgG decreased with age, and then increased slightly after 45 years. However, egg, milk, soybean, wheat, corn, and rice all showed a decreasing positive rate with the increase of age. The increase of chicken, pork and cod was observed in childhood, and then decreased with age, and then increased in middle and old age. Conclusions: There may be a certain correlation between food intolerance and elevated food sIgG levels in Beijing area. It is suggested that patients of different genders and ages should be optimized and adjusted according to their own characteristics, and children patients are still the key population for food intolerance control.

The role of Desmodium intortum, Brachiaria sp. and Phaseolus vulgaris in the management of fall armyworm Spodoptera frugiperda (J. E. Smith) in maize cropping systems in Africa

BACKGROUNDThe fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) is a serious pest of maize. Farming systems such as push‐pull or maize‐legume intercropping have been reported to reduce FAW infestations significantly. However, the exact mechanisms involved in FAW management have not been practically elucidated. We therefore assessed larval host preference, feeding and survival rate when exposed to four host plants commonly used in push‐pull and legume intercropping. We also compared adult moths' oviposition preference between maize and other grasses used as trap crops in push‐pull.RESULTSThe larval orientation and settlement study showed that maize was the most preferred host plant followed by bean, desmodium and Brachiaria brizantha cv Mulato II. The larval arrest and dispersal experiment showed that mean number of larvae was significantly higher on maize than on Desmodium or B. brizantha cv Mulato II. However, no significant differences were found between maize and bean after 24 h. Maize was the most consumed plant, followed by bean, desmodium and finally brachiaria. The mean percentage of survival to the pupation stage was significantly higher on maize. The study on FAW oviposition preference showed no significant differences in egg deposited between maize and other grasses. However, B. brizantha cv Xaraes, which received more eggs than maize, could be a promising alternative to B. brizantha cv Mulato II for the control of FAW.CONCLUSIONThe study provides a better understanding of the mechanisms involved in the control of fall armyworm under the push‐pull and maize legume intercropping. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The Effects of High-Altitude Windborne Migration on Survival, Oviposition, and Blood-Feeding of the African Malaria Mosquito, Anopheles gambiae s.l. (Diptera: Culicidae)

Recent results of high-altitude windborne mosquito migration raised questions about the viability of these mosquitoes despite ample evidence that many insect species, including other dipterans, have been known to migrate regularly over tens or hundreds of kilometers on high-altitude winds and retain their viability. To address these concerns, we subjected wild Anopheles gambiae s.l. Giles mosquitoes to a high-altitude survival assay, followed by oviposition (egg laying) and blood feeding assays. Despite carrying out the survival assay under exceptionally harsh conditions that probably provide the lowest survival potential following high altitude flight, a high proportion of the mosquitoes survived for 6- and even 11-h assay durations at 120- to 250-m altitudes. Minimal differences in egg laying success were noted between mosquitoes exposed to high altitude survival assay and those kept near the ground. Similarly, minimal differences were found in the female's ability to take an additional bloodmeal after oviposition between these groups. We conclude that similar to other high-altitude migrating insects, mosquitoes are able to withstand extended high-altitude flight and subsequently reproduce and transmit pathogens by blood feeding on new hosts.

Differences in Egg and Milk Food Challenge Outcomes Based on Tolerance to the Baked Form

To determine if a history of tolerance versus avoidance of baked egg or cow’s milk influenced the outcomes of an oral food challenge to egg or whole cow’s milk.The study included 569 pediatric patients who underwent egg or cow’s milk oral challenges at the Children’s Hospital of Philadelphia from 2012 to 2015.This was a retrospective chart review of pediatric patients who underwent whole egg and cow’s milk oral food challenges.More patients passed the whole egg food challenge if they previously tolerated baked egg (75%) versus avoidance (58%, P = .01) or never ingested (45%, P < .0001). Among the positive reactions, those patients who tolerated baked egg reacted at higher doses (3.0 g) and required epinephrine less often (10%) than those patients with egg avoidance (0.69 g, P = .03; 22%, P = .02) or who never ingested (0.88 g, P = .01; 32%, P = .0001). No difference was found among patients with cow’s milk allergy. Those who never ingested egg or cow’s milk had the poorest oral food challenge outcomes and the highest rates of atopic dermatitis (66% for patients with egg allergy and 86% for patients with milk allergy).This study shows that children who were known to be able to tolerate baked egg had higher food challenge pass rates (tolerance). Additionally, in those patients who did react, they were able to tolerate higher doses and had less-severe reactions if they previously tolerated baked egg. This association was not observed with patients with cow’s milk allergy.Known tolerance of baked egg may be a helpful marker for identifying children who will have more favorable food challenge outcomes. Although the effects of including baked egg in the diet on altering the natural history of egg allergy remains inconclusive, the results of this study support that tolerance of baked egg may help to promote tolerance of concentrated egg. Patients should be evaluated by an allergist early to possibly allow for introduction of baked egg into the diet. If baked egg tolerance has been established, the pediatrician can encourage parents to continue it in the diet. Further studies are needed to determine if the same benefit may be seen with cow’s milk and identify markers for favorable food challenge outcome.

Life-history consequences of bidirectional selection for male morph in a male-dimorphic bulb mite

Intralocus sexual conflict (IASC) arises when males and females have different trait optima. Some males pursue different alternative reproductive tactics (ARTs) with different trait optima, resulting in different strengths of IASC. Consequently, for instance daughter fitness is differentially affected by her sire’s morph. We tested if—and which—other life-history traits correlatively change in bidirectional, artificial selection experiments for ARTs. We used the male-dimorphic bulb mite Rhizoglyphus robini, the males of which are high-fitness ‘fighters’ or low-fitness ‘scramblers’. Twice in each of the five generations of selection, we assessed clutch composition (number of mites of the various life stages present) and size (total number of offspring). Furthermore, we tracked offspring from egg to adulthood in the first and final generation to detect differences between selection lines in the size and duration of stages, and in maturation time. We found that selection for male morph increased the frequency of that morph. Furthermore, compared to fighter lines, scrambler lines produced more females, which laid larger eggs (in the final generations), and maintained a higher egg-laying rate for longer. Otherwise, our results showed no consistent differences between the selection lines in clutch size and composition, life stage size or duration, or maturation time. Though we found few correlated life-history trait changes in response to selection on male morph, the differences in egg laying rate and egg size suggest that IASC between fighters is costlier to females than IASC with scramblers. We hypothesize that these differences in reproductive traits allow fighter-offspring to perform better in small, declining populations but scrambler-offspring to perform better in large, growing populations.

Biotic and abiotic factors influencing channel catfish egg and gut microbiome dynamics during early life stages

This study quantified the effects of pond rearing environments on microbial community composition in larval channel catfish (Ictalurus punctatus) gastrointestinal (GI) tracts across early developmental stages. Larvae were reared under standard industry conditions and sampled at five developmental stages (Egg, Swim-up, Day of stocking, 24 h post-stocking, and 21 d post-stocking). Massive-parallel sequencing of a segment of the 16S rRNA gene was conducted using an Illumina MiSeq platform to characterize the diversity and taxonomic composition of gut and water microbial communities. PERMANOVA analyses of differences in egg and gut microbial community composition across stages indicated a significant interaction between nursery pond environment, and family (P < 0.05) during the last two stages. Proteobacteria and Firmicutes genera along with genera including Vibrio, Aeromonas and Flavobacterium were associated with differences in gut bacterial community composition during larval development before and after pond stocking. Our study demonstrates that the aquatic rearing environment is an important factor influencing the transfer of microbes from water or food into the gut, and provides insight concerning the niche and ecological adaptability of microbes inside the channel catfish gut. Findings demonstrating that catfish gut community composition is highly variable over time indicates probiotic treatments may be possible, however gut community manipulation would require concurrent manipulation of pond or other environmental regimes and microbial communities.

Resistance of Uganda soybean germplasm to Adzuki bean bruchid

Soybean (Glycine max (L.) Merrill) is among the major food and industrial crops grown globally for its high protein and oil content. Lately, in Uganda, soybean reportedly faces challenges with a storage pest, Callosobruchus chinensis. This study was carried out to quantify the damage caused by the pest and identify the sources of resistance in the germplasm in Uganda. The study was conducted at Makerere University Agricultural Research Institute, Kabanyolo (MUARIK) in Uganda, during 2015 and 2016. Callosobruchus chinensis was used to challenge 498 soybean lines under no choice condition, in the laboratory. Results showed no significant differences in eggs laid amongst the different genotypes; however the genotypes performed significantly different (P< 0.05) for adult insect emergence, median development period (MDP), Dobie susceptibility index (DSI), growth index (GI), insect percent emergence (% IE) and seed weight loss (%WL). Genotype AVRDC G8527 had the lowest % IE (6.31), DSI (0.7), % WL (0.02) and GI (0.07), suggesting high resistance. Weight loss of up to 27% was recorded in genotype USA 7. There was a strong positive correlation between number of adults that emerged with DSI (r=0.87), eggs (r=0.88), % weight loss (r=0.73), and growth index (r=0.996). Cluster analysis revealed that AVRDC G8527, a resistant genotype was closely related to S-line 13.2A, a moderate resistant genotype. Regression analysis, revealed that adult bruchid emergence explain seed weight loss with 62% coefficient of determination; while seed colour could be used to determine genotype DSI with up to 74% coefficient of determination. Genotypes AVRDC G8527 and G89 were identified as the most resistant genotypes based on levels of DSI. Keywords : Callosobruchus chinensis, Dobie susceptibility index, seed weight loss

Differences in egg and milk food challenge outcomes based on tolerance to the baked form

BackgroundPrevious studies suggest inclusion of baked egg and milk in the diet of children with egg or cow's milk (CM) allergy might positively affect native tolerance. However, differences in native food reactivity based on historical baked tolerance are not fully understood. ObjectiveTo assess differences in native egg and CM oral food challenge (OFC) outcomes based on presenting history of tolerance and exposure to these foods in the baked form. MethodsThis study is a retrospective review of all egg and CM OFCs at the Children's Hospital of Philadelphia (Philadelphia, Pennsylvania) over 4 years (N = 580). History of baked ingestion was compared with OFC pass rate, eliciting dose, epinephrine use, reaction classification, and recent skin test reaction or specific immunoglobulin E level. ResultsThere were 115 egg- and 70 CM-positive challenge reactions, with most eliciting anaphylaxis. Children tolerating baked egg passed OFC more frequently (75%) compared with children who avoided baked egg (58%; P = .01) or never ingested egg (45%; P < .0001). For positive reactions, children tolerant of baked egg reacted at higher eliciting doses of native egg (median 3.0 g, range 0.125–15.75 g) compared with those avoiding baked egg (median 0.69 g, range 0.13–10.0 g; P = .03) and those with no egg exposure (median 0.88 g, range 0.13–13.88 g; P = .01). Further, epinephrine use was lower in children tolerating baked egg (10%) compared with children avoiding baked egg (22%; P = .02) and compared with children who never ingested egg (32%; P = .0001). These differences were not observed for CM challenges. ConclusionChildren who historically tolerated baked egg were less sensitive to native egg during OFC compared with children whose baked reactivity was largely unknown.