Dietary Black Soldier Fly ()-Dipterose-BSF-Enhanced Zebrafish Innate Immunity Gene Expression and Resistance to Infection.

Dietary management using immunostimulants to protect fish health and prevent bacterial infection is widely practiced. Many insect species possess various bioactive substances that can improve animal health. We previously identified several bioactive polysaccharides derived from insects, including dipterose-BSF from black soldier fly () larvae; this can stimulate innate immunity in mammalian macrophage RAW264.

Effects of dietary silkrose of Antheraea yamamai on gene expression profiling and disease resistance to Edwardsiella tarda in Japanese medaka (Oryzias latipes).

We previously identified a novel acidic polysaccharide, silkrose-AY, from the Japanese oak silkmoth (Antheraea yamamai), which can activate an innate immune response in mouse macrophage cells. However, innate immune responses stimulated by silkrose-AY in teleosts remain unclear. Here, we show the influence of dietary silkrose-AY in medaka (Oryzias latipes), a teleost model, in response to Edwardsiella tarda infection.

The Dipterose of Black Soldier Fly ) Induces Innate Immune Response through Toll-Like Receptor Pathway in Mouse Macrophage RAW264.7 Cells.

In our study, a novel bioactive polysaccharide was identified in the larvae of the black soldier fly (BSF) () as a molecule that activates the mammalian innate immune response. We attempted to isolate this molecule, which was named dipterose-BSF, by gel-filtration and anion-exchange chromatography, followed by nitric oxide (NO) production in mouse RAW264.7 macrophage cells as a marker of immunomodulatory activity.

Replacement of Fish Meal by Defatted Yellow Mealworm () Larvae in Diet Improves Growth Performance and Disease Resistance in Red Seabream ().

Yellow mealworm () larvae are a potential alternative animal protein source for sustainable aquaculture. However, reports on the successful complete substitution of fish meal with yellow mealworm larvae in an aquaculture diet have been limited. In this study, we conducted a feeding trial with red seabream () being fed diets with partial or complete replacement of fish meal with yellow mealworm larvae defatted with a hexane⁻ethanol solution.

Evaluation of Black Soldier Fly () Larvae and Pre-Pupae Raised on Household Organic Waste, as Potential Ingredients for Poultry Feed.

Black soldier fly (BSF) larvae and pre-pupae could be satisfactorily raised on household organic waste and used as poultry feed, offering a potential sustainable way to recycle untapped resources of waste. The present study was conducted to determine if whole (non-defatted) BSF larvae and pre-pupae raised on experimental household waste could substitute soybean meal and oil as ingredients for laying hen diets. While no significant differences in feed intake and the egg-laying rate of hens were observed throughout the experiment, egg weight and eggshell thickness were greater in the pre-pupae-fed group than in the other groups.

Sex-changing patterns of Akoya pearl oyster ().

Background: Pearl production by transplantation in Akoya pearl oyster is a biotechnology developed in Japan that skillfully utilizes the pearl-forming ability of oysters. In this method, cultured pearls are formed from a pearl nucleus and a small piece of mantle transplanted into the gonads of recipient pearl oysters. In this study, we hypothesized that the sex of the recipient pearl oyster might affect the quality of pearl produced.

The silkrose of Bombyx mori effectively prevents vibriosis in penaeid prawns via the activation of innate immunity.

We previously identified novel bioactive polysaccharides from Bactrocera cucurbitae and Antheraea yamamai that activate innate immunity in RAW264 murine macrophages. However, in terms of potential applications in the cultivation of prawns, there were problems with the availability of these insects. However, we have now identified a polysaccharide from Bombyx mori that activates innate immunity in RAW264 cells and penaeid prawns.

Effect of the squid viscera hydrolysate on growth performance and digestion in the red sea bream Pagrus major.

The improvement in feed efficiency is one of the most important subjects in fish culture. The development of feed, in terms of good intake, high growth performance, and high feed efficiency is needed. Squid viscera are one of the candidates for alternative material in improving feed efficiency in fish culture.

Silkrose: A novel acidic polysaccharide from the silkmoth that can stimulate the innate immune response.

We have identified a novel acidic polysaccharide from silkmoth (Antheraea yamamai) pupae that activates the mammalian innate immune response. This bioactive polysaccharide was isolated using nitric oxide production in mouse RAW264 macrophages as an indicator of immunostimulatory activity. We named this polysaccharide "silkrose".

A novel polysaccharide in insects activates the innate immune system in mouse macrophage RAW264 cells.

A novel water-soluble polysaccharide was identified in the pupae of the melon fly (Bactrocera cucurbitae) as a molecule that activates the mammalian innate immune response. We attempted to purify this innate immune activator using nitric oxide (NO) production in mouse RAW264 macrophages as an indicator of immunostimulatory activity. A novel acidic polysaccharide was identified, which we named "dipterose", with a molecular weight of 1.

Examination of digestive enzyme distribution in gut tract and functions of intestinal caecum, in megascolecid earthworms (Oligochaeta: Megascolecidae) in Japan.

Earthworms ingest various materials in addition to food items, such as soil particles. Most earthworms of the family Megascolecidae, a dominant family in Japan, have intestinal caeca connected directly to the intestinal tract. The function of the caeca has not been demonstrated, although it is thought to be associated with digestion.

Trypsin regulates meiotic initiation in the Japanese eel (Anguilla japonica) by promoting the uptake of taurine into germ cells during spermatogenesis.

Meiosis is a unique and critical process in reproduction. Although the key molecular components of meiosis have been identified, the molecular mechanisms regulating the entry into this pathway remain unclear. We previously demonstrated that a progestin in teleost fish, 17alpha, 20beta-dihydroxy-4-pregnen-3-one, is essential for meiotic initiation, and up-regulates taurine synthesis and the production of trypsin in Sertoli cells.

A xenograft mantle transplantation technique for producing a novel pearl in an akoya oyster host.

The brightness and color of pearls varies among different pearl-producing shellfish and have been a source of human fascination since ancient times. When produced through cultivation, the characteristics and quality of a pearl depend on the kind of shellfish used and also the transplanted mantle graft. This suggests that the Akoya pearl oyster, which is generally used in Japan for pearl culturing, can produce different kinds of pearl through the use of mantles from different species of shellfish.

Proliferating spermatogonia are susceptible to reactive oxygen species attack in Japanese eel (Anguilla japonica).

Oxidative stress has been implicated in pathogenesis of many diseases, but few studies describe its influence on spermatogenesis. In this study, we analyzed the direct influence of hypoxanthine (Hx)-induced reactive oxygen species (ROS) on spermatogenesis in fish using the Japanese eel (Anguilla japonica) testicular organ culture system. Testicular fragments of eels were cultured in 0.

Gonads directly regulate growth in teleosts.

In general, there is a relationship between growth and reproduction, and gonads are known to be important organs for growth, but direct evidence for their role is lacking. Here, using a fish model, we report direct evidence that gonads are endocrine organs equal to the pituitary in controlling body growth. Gonadal loss of function, gain of function, and rescue of growth were investigated in tilapia.

Taurine plays an important role in the protection of spermatogonia from oxidative stress.

It has been demonstrated that taurine has various physiological functions in the body. We demonstrated that taurine is abundant in the serum, liver, muscle and testis of the Japanese eel (Anguilla japonica). In the eel testis, taurine is found mainly in spermatogonia and is weakly expressed also in the Sertoli cells.

Molecular characterization and gene expression of Japanese eel (Anguilla japonica) gonadotropin receptors.

A luteinizing hormone receptor (lhr) cDNA with high identity to other fish lhrs was fully cloned from the ovary of the Japanese eel (Anguilla japonica). The genes for two gonadotropin receptors (Gthr), follicle-stimulating hormone receptor (fshr) and lhr, were differentially expressed during oogenesis, which was artificially induced by salmon pituitary extract, a gonadotropin-rich source. Transcript abundance of fshr was significantly elevated at the early vitellogenic stage and peaked at the late vitellogenic stage, while lhr gene expression rapidly induced at the late vitellogenic stage and thereafter remained at a high level.

The synthesis and role of taurine in the Japanese eel testis.

In teleost fish, the progestin 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) is an essential component of the spermatogenesis pathway. In a series of investigations on the mechanisms underlying progestin-stimulated spermatogenesis, we have found that DHP up-regulates the expression of cysteine dioxygenase1 (CDO1) in the Japanese eel testis. CDO1 is one of the enzymes involved in the taurine biosynthesis pathway.

Gh is produced by the testis of Japanese eel and stimulates proliferation of spermatogonia.

Gh plays important roles in development, somatic growth and gametogenesis in vertebrates. To determine the physiological role of Gh in reproduction in male teleosts, the expression of genes encoding Gh and the two Gh receptors (Ghrs) during spermatogenesis, and the action of Gh in vitro was examined using the Japanese eel (Anguilla japonica). gh, ghr1 and ghr2 mRNA transcripts were detected in all spermatogenic stages.

Tolerance of spermatogonia to oxidative stress is due to high levels of Zn and Cu/Zn superoxide dismutase.

Background: Spermatogonia are highly tolerant to reactive oxygen species (ROS) attack while advanced-stage germ cells such as spermatozoa are much more susceptible, but the precise reason for this variation in ROS tolerance remains unknown.

Methodology/principal Findings: Using the Japanese eel testicular culture system that enables a complete spermatogenesis in vitro, we report that advanced-stage germ cells undergo intense apoptosis and exhibit strong signal for 8-hydroxy-2'-deoxyguanosine, an oxidative DNA damage marker, upon exposure to hypoxanthine-generated ROS while spermatogonia remain unaltered. Activity assay of antioxidant enzyme, superoxide dismutase (SOD) and Western blot analysis using an anti-Copper/Zinc (Cu/Zn) SOD antibody showed a high SOD activity and Cu/Zn SOD protein concentration during early spermatogenesis.

Anti-viral effects of interferon administration on sevenband grouper, Epinephelus septemfasciatus.

Interferon (IFN) plays crucial roles in innate immune responses against viral infections. In the present study, we report cloning and characterization of the IFN gene from the sevenband grouper (Epinephelus septemfasciatus), and the anti-viral effects of its recombinant IFN protein in vivo. The isolated cDNA from sevenband grouper IFN encoded a protein consisting of 178 amino acids, and its first 22 amino acids represented a putative signal peptide.

Trypsin is a multifunctional factor in spermatogenesis.

Trypsin is well known as a pancreatic enzyme that is typically secreted into the intestine to digest proteins. We show in our current study, however, that trypsin is also a key factor in the control of spermatogenesis. A progestin in teleost fish, 17alpha, 20beta-dihydroxy-4-pregnen-3-one (DHP), is an essential component of the spermatogenesis pathway, particularly during the initiation of the first meiotic division.

Zinc is an essential trace element for spermatogenesis.

Zinc (Zn) plays important roles in various biological activities but there is little available information regarding its functions in spermatogenesis. In our current study, we further examined the role of Zn during spermatogenesis in the Japanese eel (Anguilla japonica). Human CG (hCG) was injected into the animals to induce spermatogenesis, after which the concentration of Zn in the testis increased in tandem with the progression of spermatogenesis.