Accumulation Of Eggs Research Articles

Ascarid eggs disappear faster from gravel and wood chips than from soil

ABSTRACT 1. Ascarids (Ascaridia galli and Heterakis spp.) are highly prevalent in free-range laying hens. Ascarid eggs survive for long periods in soil, and one preventive measure is to add litter material to areas close to the henhouse. In this study, recovery rates of ascarid eggs from three common litter materials, namely pea gravel, beech (Fagus sylvatica) and spruce (Picea abies) wood chips were compared to recovery rates from soil. 2. Materials were mixed with faeces containing 1,408 ascarid eggs per g of faeces, placed in plastic fruit boxes and exposed to natural weather conditions in a randomised block design with six replicates per treatment. 3. Numbers of ascarid eggs were quantified at 28 time points over 3.5 years. Ascarid eggs were recovered for over three years from all materials and completely disappeared during the fourth winter of exposure. Time needed to get to a 50% reduction in ascarid eggs did not differ between litter materials and soil (242 to 269 days). A 99% reduction was reached significantly (P < 0.001) earlier in pea gravel (548 days) than in the three other materials, and earlier in the two wood chips (day 682 for beech, day 692 for spruce, P < 0.05) than in soil (1,277 days). 4. Accumulation of ascarid eggs in the area close to the henhouse can be reduced by any of the tested litter materials compared to bare soil. Adding litter to this area is highly recommended for free-range layer farmers in order to reduce numbers of infective ascarid eggs.

Supplementation of two sources and three levels of iodine in the diet of laying hens: effects on performance, egg quality, serum and egg yolk lipids, antioxidant status, and iodine accumulation in eggs

In total, 378 Shaver White layers were allocated into 7 treatments with 6 replicates, from 30 to 42 wk of age, to assess the effects dietary organic (ethylenediamine dihydroiodide [EDDI]) versus inorganic (calcium iodate [CIOD]) iodine in laying hens. A basal diet served as control while the remaining six diets were supplemented with either CIOD (CIOD2, CIOD4, and CIOD8) or EDDI (EDDI2, EDDI4, and EDDI8) to provide 2.0, 4.0, and 8.0 mg of added iodine/kg of diet, respectively. Performance and egg quality were not affected by adding 2.0 or 4.0 mg/kg of iodine to the diets. However, a progressive decline in egg performance and feed intake occurred with EDDI8 and CIOD8 diets. The EDDI8 diet also increased abnormal eggs in parallel with decreasing the eggshell strength and Haugh unit and disturbing the serum and egg yolk lipids. This trend was connected with increase in triiodothyronine (T3) and thyroxine (T4), which led to oxidative stress in serum and egg contents. The iodine levels of eggshell and egg contents were increased by dietary iodine in a dose and time-dependent manner, while the effect of EDDI was higher than CIOD at all levels. To summary, supplementation of diets with 2 or 4 mg/kg of iodine as CIOD and specifically EDDI increased the iodine content of eggs without adverse effect on hen performance and egg quality traits. However, considering the time-dependent nature of this increase, a 12-wk period of supplementation might be not sufficient to achieve a specified level of iodine in the eggs. Highlights Diet supplementation with 2, 4, and 8 mg/kg of iodine as CIOD and EDDI increased iodine content of eggs. The highest level of iodine, especially as EDDI, diminished egg performance and egg quality connected with an increase in serum T3 and T4, which led to oxidative stress. A 12-wk period of supplementation appears to be not sufficient to achieve a specified level of iodine in the egg.

Monocyte and Macrophage-Mediated Pathology and Protective Immunity During Schistosomiasis.

Infection by Schistosoma parasites culminates in a chronic granulomatous disease characterized by intense tissue fibrosis. Along the course of schistosomiasis, diverse leukocytes are recruited for inflammatory foci. Innate immune cell accumulation in Th2-driven granulomas around Schistosoma eggs is associated with increased collagen deposition, while monocytes and macrophages exert critical roles during this process. Monocytes are recruited to damaged tissues from blood, produce TGF-β and differentiate into monocyte-derived macrophages (MDMs), which become alternatively activated by IL-4/IL-13 signaling via IL-4Rα (AAMs). AAMs are key players of tissue repair and wound healing in response to Schistosoma infection. Alternative activation of macrophages is characterized by the activation of STAT6 that coordinates the transcription of Arg1, Chi3l3, Relma, and Mrc1. In addition to these markers, monocyte-derived AAMs also express Raldh2 and Pdl2. AAMs produce high levels of IL-10 and TGF-β that minimizes tissue damage caused by Schistosoma egg accumulation in tissues. In this review, we provide support to previous findings about the host response to Schistosoma infection reusing public transcriptome data. Importantly, we discuss the role of monocytes and macrophages with emphasis on the mechanisms of alternative macrophage activation during schistosomiasis.

Effects of Replacing Inorganic with Organic Iron on Performance, Egg Quality, Serum and Egg Yolk Lipids, Antioxidant Status, and Iron Accumulation in Eggs of Laying Hens.

This study compared the effects dietary organic (ferrous glycine [FG]) versus inorganic (ferrous sulfate [FS]) iron in laying hens on performance, egg quality, serum and egg yolk lipids, antioxidant status, and iron enrichment of eggs. A total of 378 Shaver White layers were allotted to 7 treatments with 6 replicates (9 birds each) from 30 to 42weeks of age. A basal diet (19mg iron/kg) served as control, while the other six diets were supplemented with either FS or FG to provide 30, 60, and 120mg/kg of added iron. Dietary FG and FS treatments improved (P < 0.05) laying rate, egg weight, and egg quality of layers, relative to the control, albeit eggshell strength and eggshell calcium also deteriorated with the highest level of FS (P< 0.05). The iron treatment groups exhibited a lower serum and egg yolk levels of triglycerides, total cholesterol, and low-density lipoprotein cholesterol that accompanied by higher levels of high-density lipoprotein cholesterol and greater activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) as compared with the control (P < 0.05). The contents of malondialdehyde and protein carbonyl were conversely related to the activities SOD and GPx (P < 0.05). The serum and egg fractions (yolk, albumen, and shell) displayed gradually increases in iron contents as the level of iron increased in the diet (P < 0.05), while FG was superior to FS at all tested levels (P < 0.05). To summary, FS can be replaced by FG, with more favorable impacts on egg quality and iron enrichment.

Lead Exposure Influences Serum Biomarkers, Hepatocyte Survival, Bone Marrow Hematopoiesis, and the Reproductive Cycle in Japanese Quails.

Lead toxicity has been a hallmark issue of toxicology over the last decades. However, predictive and non-robust models did not provide complete data on low-dose lead interaction with the organism at different functional levels (e.g., blood-serum-liver-bone marrow-bursa fabricii-reproductive system axis). Japanese quails are an animal model with a strong immune system, making them suitable for the thorough assessment of in vivo chronic lead toxicity. In this study, we have exposed Japanese quails via water ingestion to 0.25 and 0.5 μg/mL lead(II) chloride (PbCl2) for 20 days and assessed blood cells, serum biomarkers, hepatocyte survival, bone marrow hematopoiesis, bursa fabricii, and lead accumulation in eggs. Blood cells passed through morphological alterations (loss and inversion of the erythrocyte nucleus, multiple erythrocyte and thrombocyte aggregation, lymphocyte degradation, and blast cell infiltration). In the serum, PbCl2 increased the activity of creatine kinase (CK) and lactate dehydrogenase (LDH); increased the level of cholesterol, sodium, creatinine, and urea; and reduced the level of proteins, triglycerides, chloride, potassium, calcium, and alkaline phosphatase (ALP) activity (P < 0.05). Liver tissue of the exposed animals exhibited apparent death of hepatocytes. In the bone marrow, macrophages and heterophils contained a vast number of the infiltrated/uptaken granules upon PbCl2 exposure. Ultimately, PbCl2 exposure elicited a series of events observed first in the blood and serum parameters and later translated to the hematopoietic centers.

(+)-(R)- and (−)-(S)-Perhexiline maleate: Enantioselective synthesis and functional studies on Schistosoma mansoni larval and adult stages

Schistosomiasis is a neglected tropical disease mainly affecting the poorest tropical and subtropical areas of the world with the impressive number of roughly 200 million infections per year. Schistosomes are blood trematode flukes of the genus Schistosoma causing symptoms in humans and animals. Organ morbidity is caused by the accumulation of parasite eggs and subsequent development of fibrosis. If left untreated, schistosomiasis can result in substantial morbidity and even mortality. Praziquantel (PZQ) is the most effective and widely used compound for the treatment of the disease, in prevention and control programs in the last 30 years. Unfortunately, it has no effect on juvenile immature schistosomes and cannot prevent reinfection or interfere with the schistosome life cycle; moreover drug-resistance represents a serious threat. The search for an alternative or complementary treatment is urgent and drug repurposing could accelerate a solution. The anti-anginal drug perhexiline maleate (PHX) has been previously shown to be effective on larval, juvenile, and adult stages of S. mansoni and to impact egg production in vitro. Since PHX is a racemic mixture of R-(+)- and S-(−)-enantiomers, we designed and realized a stereoselective synthesis of both PHX enantiomers and developed an analytical procedure for the direct quantification of the enantiomeric excess also suitable for semipreparative separation of PHX enantiomers. We next investigated the impact of each enantiomer on viability of newly transformed schistosomula (NTS) and worm pairs of S. mansoni as well as on egg production and vitellarium morphology by in vitro studies. Our results indicate that the R-(+)-PHX is mainly driving the anti-schistosomal activity but that also the S-(−)-PHX possesses a significant activity towards S. mansoni in vitro.

In vivo cultivation of tuna blood fluke Cardicola orientalis in terebellid intermediate hosts

Some fish blood flukes of the genus Cardicola (Aporocotylidae) are considered important pathogens of farmed/ranched tuna, Thunnus spp. Infections with Cardicola spp. might obstruct the blood flow in the gills via massive accumulations of eggs and often lead to mass mortalities in captive tuna. At present, oral administration of an anthelminthic drug, praziquantel is the most effective treatment, but the tuna farming industries are seeking non-drug control measures. Development of prophylactic and holistic measures have been difficult, owing to a lack of basic knowledge about these parasites. Unlike other trematodes which use molluscs, blood flukes of marine actinopterygian fish use terebellid polychaetes as intermediate hosts. However, information about the development of Cardicola spp. within intermediate hosts is very limited. Recent success in Cardicola opisthorchis sporocyst transplantation into the host polychaete has opened possibilities for the cultivation of Cardicola in the laboratory. Here, we conducted several transplantation trials with another tuna blood fluke, Cardicol orientalis, into its natural and surrogate polychaete hosts. Cardicola orientalis sporocysts were injected into a total of 195 Nicolea gracilibranchis, the natural host, and clear sporocyst development and reproduction was observed in 32 recipients (overall success rate 16.4%). The production of daughter sporocysts in the transplanted polychaete occurred within 14 days post injection, and one sporocystogenous cycle took approximately 4 weeks. Serial passage culture via transplantation of in vivo-cultured sporocysts was also achieved, but with limited sporocyst reproduction. In addition, sporocysts were successfully retrieved from six and one individuals of the surrogate hosts, Thelepus setosus (n = 10) and Thelepus japonicus (n = 5), respectively. These results indicate that the in vivo cultivation of C. orientalis sporocysts is possible, not only in its natural host but also in other terebellids, although the problems of high mortality and inconsistency in successful transplantation need to be resolved.

Dystocia in Nymphicus hollandicus with metabolic complications due to renal ischemia: case report

Dystocia in psitacides is common, being defined as an obstruction of the reproductive tract by one or more eggs, due to problems in its formation, as well as to be influenced factors such as physical, nutritional, and genetic among others. The present study aimed to report a clinical case of a female Nymphicus hollandicus, with about two-year-old presenting with ischemic renal complications secondary to prolonged maintenance, attended at the Hospital Metropolitan veterinarian of the municipality of Caucaia – Ceará, diagnosed with dystocia after anamnesis, physical examination and radiography abdominal. After contamination of the condition, treatment was established support followed hours observes three eggs free in the celtic cavity, oviduct rupture, egg adherence medium with the intestine, and renal ischemia. It can be concluded that in cases of dystocia associated with late treatment there is a greater possibility of occurrence of metabolic impairment due to the accumulation of eggs in the cavity, favoring the rupture of oviduct, adhesion and ischemia of other organs.

Comparative impact of coumaphos, amitraz and plant extract of Ageratum conyzoides on the oogenesis of Rhipicephalus microplus

The present experiment was conducted to evaluate and compare the impact of Ageratum conyzoides plant extract (ACE) with routinely used synthetic acaricides i.e., amitraz and coumaphos on the oogenesis of engorged adult females of Rhipicephalus microplus tick. On the day of dropping from the host, panoistic ovary of R. microplus appeared white in colour, horseshoe shaped, hollow tubular organ with immature oocytes predominantly in dorsal groove. Different developmental stages of oocytes (I–V) proceed simultaneously and asynchronously. Oocytes showed gradual increase in size, deep brown colored with accumulation of eggs in oviduct during 24–72 hours of development.At LC90 concentration a highly significant (p < 0.001) cessation of egg laying after exposure to amitraz and ACE while significant reduction (p < 0.01) of egg laying in coumaphos treated ticks was observed. Upon dissection of treated ticks, uterus and oviduct packed with eggs, which failed to pass out was observed. The histo-architectural alterations including presence of extensive vacuolation, alteration of oocyte morphology, deformation of chorion and disorganization of yolk granules were observed in the treated ovaries. Histochemically, low level of storage or synthesis of essential elements viz., proteins, polysaccharides and lipids in treated oocytes responsible for reduction of fertility and inhibition of progress of vitellogenesis was observed.

The Domestic BCO2 Allele Buffers Low-Carotenoid Diets in Chickens: Possible Fitness Increase Through Species Hybridization.

Domestic animals are adapted to conditions vastly different from those of their wild ancestors, and this is particularly true for their diets. The most numerous of all domestic species, the chicken, originated from the Red Junglefowl (RJF), a native of subtropical forests in Southeast Asia. Surprisingly however, in domestic chicken breeds, a common haplotype of the β-carotene oxygenase 2 (BCO2) gene, which is involved in carotenoid metabolism, is introgressed from a related species, the Gray Junglefowl, and has been under strong selective pressure during domestication. This suggests that a hybridization event may have conferred a fitness advantage on chickens carrying the derived allele. To investigate the possible biological function of the introgressed BCO2 allele in chicken, we introgressed the ancestral BCO2 allele into domestic White Leghorn chickens. We measured gene expression as well as carotenoid accumulation in skin and eggs of chickens carrying either the ancestral or the derived BCO2 allele. The derived haplotype was associated with down-regulation of BCO2 in skin, muscle, and adipose tissue, but not in liver or duodenum, indicating that carotenoid accumulation occurred in the tissues with reduced gene expression. Most importantly, we found that hens with the derived BCO2 genotype were capable of allocating stored carotenoids to their eggs, suggesting a functional benefit through buffering any shortage in the diet during egg production. Nevertheless, it is of interest that loss of function mutations in BCO2 gene are prevalent in other domesticates including cows, rabbits, and sheep, and, given the importance of carotenoids in development, reproduction, and immunity, it is possible that derived BCO2 alleles may provide a general mechanism in multiple domestic species to deal with higher demand for carotenoids in an environment with carotenoid shortage in the diet.

Homeostatic Feedback Modulates the Development of Two-State Patterned Activity in a Model Serotonin Motor Circuit in Caenorhabditis elegans.

Neuron activity accompanies synapse formation and maintenance, but how early circuit activity contributes to behavior development is not well understood. Here, we use the Caenorhabditis elegans egg-laying motor circuit as a model to understand how coordinated cell and circuit activity develops and drives a robust two-state behavior in adults. Using calcium imaging in behaving animals, we find the serotonergic hermaphrodite-specific neurons (HSNs) and vulval muscles show rhythmic calcium transients in L4 larvae before eggs are produced. HSN activity in L4 is tonic and lacks the alternating burst-firing/quiescent pattern seen in egg-laying adults. Vulval muscle activity in L4 is initially uncoordinated but becomes synchronous as the anterior and posterior muscle arms meet at HSN synaptic release sites. However, coordinated muscle activity does not require presynaptic HSN input. Using reversible silencing experiments, we show that neuronal and vulval muscle activity in L4 is not required for the onset of adult behavior. Instead, the accumulation of eggs in the adult uterus renders the muscles sensitive to HSN input. Sterilization or acute electrical silencing of the vulval muscles inhibits presynaptic HSN activity and reversal of muscle silencing triggers a homeostatic increase in HSN activity and egg release that maintains ∼12-15 eggs in the uterus. Feedback of egg accumulation depends upon the vulval muscle postsynaptic terminus, suggesting that a retrograde signal sustains HSN synaptic activity and egg release. Our results show that egg-laying behavior in C. elegans is driven by a homeostat that scales serotonin motor neuron activity in response to postsynaptic muscle feedback.SIGNIFICANCE STATEMENT The functional importance of early, spontaneous neuron activity in synapse and circuit development is not well understood. Here, we show in the nematode Caenorhabditis elegans that the serotonergic hermaphrodite-specific neurons (HSNs) and postsynaptic vulval muscles show activity during circuit development, well before the onset of adult behavior. Surprisingly, early activity is not required for circuit development or the onset of adult behavior and the circuit remains unable to drive egg laying until fertilized embryos are deposited into the uterus. Egg accumulation potentiates vulval muscle excitability, but ultimately acts to promote burst firing in the presynaptic HSNs which results in egg laying. Our results suggest that mechanosensory feedback acts at three distinct steps to initiate, sustain, and terminate C. elegans egg-laying circuit activity and behavior.

Food Modulation Controls Astaxanthin Accumulation in Eggs of the Sea Urchin Arbacia lixula.

The carotenoid astaxanthin has strong antioxidant properties with beneficial effects for various degenerative diseases. This carotenoid is produced by some microalgae species when cultivated in particular conditions, and, interestingly, it is a predominant carotenoid in aquatic animals throughout a broad range of taxa. Recently, astaxanthin was detected in the eggs of the sea urchin Arbacia lixula in relevant concentrations when this organism was maintained in culture. These results have paved the way for deeper research into astaxanthin production by this species, particularly in regards to how astaxanthin production can be modulated by diet. Results showed that the highest content of astaxanthin in eggs was observed in sea urchins fed on a diet enriched with Spirulina platensis. This result was confirmed by the high antioxidant activity recorded in the egg extracts of these animals. Our results suggest that (i) the sea urchin A. lixula is able to synthesize astaxanthin from precursors obtained from food, and (ii) it is possible to modulate the astaxanthin accumulation in sea urchin eggs by modifying the proportions of different food ingredients provided in their diet. This study demonstrates the large potential of sea urchin cultivation for the eco-sustainable production of healthy supplements for nutraceutical applications.

Spatial and temporal patterns of nest distribution influence sexual selection in a marine fish

In many species, the natural distribution of material resources important for reproduction can profoundly impact reproductive success among individuals and, hence, the opportunity and intensity of sexual selection. Here, we report on a field‐based experiment investigating the effects of nest aggregation on sexual selection in a fish, the sand goby Pomatoschistus minutus. We found that the distribution of potential nests (sparse versus aggregated nest treatments) affected patterns of nest colonization and reproductive success. Specifically, in the treatment with aggregated nesting resources, a greater proportion of nests remained unoccupied by sand goby males. Although the size of nesting males did not differ between treatments, eggs accumulated more rapidly when nests were sparsely distributed. We found that the opportunity for selection decreased over time with the accumulation of eggs in the nests in both the aggregated and sparse treatments. Moreover, the effect of male size on reproductive success was influenced by an interaction between nest distribution and time, with the selection gradient being highest right after nest colonization when nests were aggregated, while the opposite pattern was observed in the sparse nest treatment. Such findings highlight the vital role that environmental and social factors can play in determining the importance of male phenotypic traits (in this case, male size). More broadly, our results also underscore how the natural distribution of resources, both in space and time, can impact the strength of sexual selection acting on wild animal populations.

Complementary effect of Capparis spinosa L. and silymarin with/without praziquantel on mice experimentally infected with Schistosoma mansoni

SummarySchistosomiasis remains to be the most common fibrotic disease resulting from inflammation and deposition of scar tissue around trapped parasitic eggs in the liver. Though chemotherapy eradicates matured worms efficiently and prevents the accumulation of schistosome eggs, fewer effective drugs are directed to reverse the present hepatic fibrosis. Therefore, treatment targeting hepatic fibrosis associated with schistosomiasis remains a challenging proposition.The present study was designed to investigate the potential complementary schistosomicidal and hepatoprotective activities of the methanol extract of Capparis spinosa L. (C. spinosa) with or without praziquantel (PZQ) and compare results with silymarin (Milk thistle), a known hepatoprotective and antifibrotic agent, on induced liver fibrosis by experimental Schistosoma mansoni (S. mansoni) infection. Total polyphenols in the extract were determined using colorimetric assay.C. spinosa L. caused a partial decrease in worm burden; a statistically significant reduction in hepatic and intestinal tissue egg load, what was associated histopathologically with decreasing in both the number and diameter of granulomas, as well as restoring serum aminotransferases (AST & ALT), alkaline phosphatase (ALP) and improving liver albumin synthesis. The best results were obtained in the group of mice treated with C. spinosa L. and PZQ together. Quantitative estimation of total polyphenols content using colorimetric assay showed that C. spinosa L. leaves contain higher concentration of polyphenolic compounds than fruits.It was concluded that C. spinosa L. has a promising hepatoprotective and antifibrotic properties and could be introduced as a safe and effective therapeutic tool with PZQ in the treatment of schistosomal liver fibrosis. Nevertheless further studies on the mechanism of action of C. spinosa L. in chronic liver diseases may shed light on developing therapeutic methods in clinical practice.

The effects of dietary calcium iodate on productive performance, egg quality and iodine accumulation in eggs of laying hens.

The aim of this study was to examine the effects of various levels of supplemental calcium iodate (CI) on productive performance, egg quality, blood indices and iodine (I) accumulation in the eggs in commercial laying hens. A total of 240 White Leghorn layers (Hy-line W36) were divided through a completely randomized design into six treatments with five replicates and eight hens per each at 32weeks of age. This experiment lasted for 12weeks. Concentrations of I in the mash diets were 0.74, 3.13, 5.57, 8.11, 10.65 and 12.94mg I/kg of feed in treatments 1-6 respectively. The added doses of CI were included 0.0 (control), 2.5, 5.0, 7.5, 10.0 and 12.5mg/kg of diet for treatments 1-6 respectively. There were no significant differences in productive performance among the treatments. The highest eggshell strength was observed in group fed diet containing 3.13mg I/kg (p=.014). The highest percentage of calcium and lowest percentage of phosphorus in eggshell were observed in group fed diet containing 12.94mg I/kg (p=.0001). Feeding hens with diet containing 12.94mg I/kg increased serum triiodothyronine-to-thyroxine ratio (p=.0001). Serum alanine aminotransferase activity in hens fed diet containing 12.94mg I/kg was significantly more than control (p=.041). Blood Serum triglycerides in hens fed diet containing 8.11mg I/kg were significantly higher than control (p=.0001). Edible fraction of the eggs of birds fed diet containing 12.94mg I/kg was enriched by I almost 3 times more than those fed diet containing 0.74mg I/kg. The results suggested that egg production, egg mass, feed intake and feed conversion ratio were not significantly affected by dietary I levels. Iodine accumulation in the eggs were increased by increasing dietary I levels and the level of 10mg/kg CI could supply I enrichment of the eggs.

MN and ZN content in eggs and musculature of rainbow trout ( Oncorhynchus Mykiss W. ) treated with fungicide mancozeb and pigment astaxanthin

The present study aims to determine the levels of the heavy metals manganese (Mn) and zinc (Zn) contained in the fungicide Mancozeb in the eggs and musculature of the rainbow trout (Oncorhynchus mykiss W.) which have grown in an environment, containing a permissible amount of Mancozeb and fed with or without the carotenoid pigment astaxanthin. The study follows the feeding, then the analysis of the level of Mn and Zn in the eggs and musculature of the rainbow trout, treated with and without the pigment astaxanthin and the fungicide Mancozeb. The determination of Mn and Zn concentrations is performed using a modern method for measuring macro- and microelements with an atomic absorption spectrometer, which is characterized by high selectivity, swiftness and sensitivity. Experimental data show accumulation of Mn and Zn, contained in the fungicide Mancozeb even when its concentration in the habitat does not exceed the maximum permissible levels in the normative documents. As a result, the analysis of the eggs and musculature shows the same trend regarding the accumulation of Mn and Zn. In non-fertilized, as well as in fertilized rainbow trout eggs and musculature, the experimental data show a slight increase of Mn and Zn in the presence of only astaxanthin in the added feed and a significant decrease in these metals in the presence of both astaxanthin and Mancozeb. The supplementation of astaxanthin in the diet can significantly reduce the rate of heavy metals accumulation in fish tissues and eggs, but high concentrations of these pollutants in the aquatic environment over a longer period of time would certainly result in metabolic disturbances in the fish body and reduction of their eggs’ hatchability.

The RIO protein kinase-encoding gene Sj-riok-2 is involved in key reproductive processes in Schistosoma japonicum

BackgroundSchistosomiasis is one of the most prevalent parasitic diseases worldwide and is caused by parasitic trematodes of the genus Schistosoma. The pathogenesis of schistosomiasis is caused by eggs whose production is the consequence of the pairing of schistosomes and the subsequent sexual maturation of the female. Previous studies have demonstrated that protein kinases are involved in processes leading to the male-induced differentiation of the female gonads, ovary and vitellarium. Right open reading frame protein kinase 2 (RIOK-2) is a member of the atypical kinase family and shown in other organisms to be responsible for ribosomal RNA biogenesis and cell-cycle progression, as well as involves in nematode development. However, nothing is known about its functions in any trematode including schistosome.MethodsWe isolated and characterized the riok-2 gene from S. japonicum, and detected the transcriptional profiles of Sj-riok-2 by using real-time PCR and in situ hybridization. RNAi-mediated knockdown of Sj-riok-2 was performed, mitotic activities were detected by EdU incorporation assay and morphological changes on organs were observed by confocal laser scanning microscope (CLSM).ResultsIn silico analyses of the amino acid sequence of Sj-RIOK-2 revealed typical features of this class of kinases including a winged helix (wHTH) domain and a RIO kinase domain. Sj-riok-2 is transcribed in different developmental stages of S. japonicum, with a higher abundance in adult females and eggs. Localization studies showed that Sj-riok-2 was mainly transcribed in female reproductive organs. Experiments with adult schistosomes in vitro demonstrated that the transcriptional level of Sj-riok-2 was affected by pairing. Knocking down Sj-riok-2 by RNAi reduced cell proliferation in the vitellarium and caused the increased amount of mature oocytes in ovary and an accumulation of eggs within the uterus.ConclusionsSj-riok-2 is involved in the reproductive development and maturation of female S. japonicum. Our findings provide first evidence for a pairing-dependent role of Sj-riok-2 in the reproductive development and maturation of female S. japonicum. Thus this study contributes to the understanding of molecular processes controlling reproduction in schistosomes.

Egg accumulation with 3D embryos provides insight into the life history of a pterosaur.

Fossil eggs and embryos that provide unique information about the reproduction and early growth of vertebrates are exceedingly rare, particularly for pterosaurs. Here we report on hundreds of three-dimensional (3D) eggs of the species Hamipterus tianshanensis from a Lower Cretaceous site in China, 16 of which contain embryonic remains. Computed tomography scanning, osteohistology, and micropreparation reveal that some bones lack extensive ossification in potentially late-term embryos, suggesting that hatchlings might have been flightless and less precocious than previously assumed. The geological context, including at least four levels with embryos and eggs, indicates that this deposit was formed by a rare combination of events, with storms acting on a nesting ground. This discovery supports colonial nesting behavior and potential nesting site fidelity in the Pterosauria.

Quantification of enrofloxacin residues in broiler chicken tissues using competitive enzyme-linked immunosorbent assay

Irrational use of antimicrobial agents’ results in their accumulation in poultry eggs, meat and other byproducts. Less is known regarding antimicrobial residues in broiler meat, specifically for Jhang, Punjab, Pakistan. Thus, the main purpose of this research was to evaluate the prevalence of enrofloxacin residues in broiler chickens tissue. A total of 90 samples of chickens’ tissue were collected randomly from different local meat shops of Jhang city and were analyzed using competitive colorimetric enzyme-linked immunosorbent assay kit. Out of 90 samples analyzed, 53% of the breast muscle and 62% of the liver tissues samples contained residues of enrofloxacin higher than maximum residue limits. Median concentration of enrofloxacin residues in breast muscle and liver tissue was 103 ng/g and 1409 ng/g respectively. Quantification of antibiotic residues distribution in chickens’ tissues revealed that the difference between breast muscle and liver tissue was non-significant. Results of study revealed that broiler chickens being sold in Jhang city contained the enrofloxacin residues and may exposethe consumers to their deleterious effects.

The influence of dietary arachidonic acid on growth, reproductive performance, and fatty acid composition of ovary, egg and larvae in an anabantid model fish, Blue gourami (Trichopodus trichopterus; Pallas, 1770)

This study investigates the influence of arachidonic acid (ARA) on growth, reproductive performance, and fatty acid compositions of ovary, egg and 3-DPH (days post hatching) larvae of Trichopodus trichopterus broodstock. A 150-day feeding experiment was performed comparing the effects of five ARA-supplemented diets containing 0 (control), 0.5, 1, 1.5 and 2% ARA (of total fatty acids) (TFA). Growth parameters including final weight, weight gain and specific growth rate (SGR) did not differ between different groups (P>0.05). Feed conversion ratio (FCR) was significantly lower in control group compared to 0.5 and 1.5% ARA groups (P<0.05). Contrary to growth indices, all reproductive traits were significantly affected by ARA contents in diets. Absolute and relative fecundities increased in relation to the ARA content (P<0.05). The maximum absolute and relative fecundities (13.3 and 974.3×103, respectively) were recorded in 2% ARA treatment group (P<0.05). Mean oocyte diameter reached the greatest size (861.66μm) in 1% ARA and was significantly different than other treatments (P<0.05). The yolk sac diameter was enhanced linearly by increasing dietary ARA (P<0.05). Results showed striking effects of dietary ARA on its accumulation in ovaries, eggs and larva. Ʃ n−6 series fatty acid (44.9%) and its constituent (18:2n−6) (40.85%) reached the highest contents in 0.5% ARA in ovaries (P<0.05). A similar trend was seen in fertilized eggs and 3-DPH larvae in that the highest amounts of 18:2-6 and Σ n−6 were found in the 0.5% ARA group (P<0.05). A second order polynomial regression was employed for estimating ARA/EPA (eicosapentaenoic acid) ratios and showed that the respective ratio enhanced linearly in the ovary and fertilized egg. Correspondingly, ARA/DHA (docosahexaenoic acid) ratio in ovary, fertilized egg and larvae reflected those of the experimental diets. Their fatty acid profiles reflect the diet composition well, ovary (R2=0.87), fertilized egg (R2=0.91) and 3DPH larvae (R2=0.82) and the ARA/DHA ratios were linearly improved by increasing dietary ARA (P<0.05). Overall, the results of this study revealed the necessity of ARA inclusion in T. trichopterus broodstock diets. This conclusion challenges the generally accepted hypothesis that freshwater fish meet their highly unsaturated fatty acids (HUFA) requirements by elongation and desaturation their precursors. These findings showed that T. trichopterus broodstock, as a model of asynchronous multi-batch spawning fish, needs to receive at least 1% ARA in their maturation diet to improve reproductive performance. The best efficiency was achieved in 2% ARA, based on fecundity, yolk sac diameter and hatching rate.