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The differentiation and variation of body color in fish is an important component of biological evolution and phylogenetic research, and is influenced by several factors such as heredity, nutrition, physiological hormones and rearing conditions, with heredity being the most critical factor. An improved comprehension of the genetic regulation in different carp populations will facilitate future applications of precision breeding and pigment cell development-related genes editing. In this study, we used restriction site-associated DNA sequencing (2d-RAD) to determine the distribution characteristics of single nucleotide polymorphisms (SNPs) in eight common carp strains including six koi strains, i.e., Kohaku (Hb), Taisho (Dz), Showa (Zh), Golden (Hj), Matsukawabake (Sch) and Five-color (Ws), and two genetically improved breeding strains, i.e., FFRC No. 2 strain (Fr) and red FFRC strain (Hfr), and then SNP markers to resolve genetic information on the population structure and skin color formation of these strains. We found that most individuals of eight strains were clearly divided into eight clades. Genetic diversity within Fr, Sch and Ws is relatively high, while it is low within Dz, Hb and Hfr. A comparison between the populations revealed that Hfr and Ws have the highest degree of genetic differences, while Hb and Dz have the lowest. The GWAS analysis for two strategies identified several SNPs that are significantly related to skin color variation and affect melanin synthesis (ephrinb 2 , slc 22 a 23 , herc 2 , ephb 2), carotenoid metabolism (oca 2 , bcmo 1 , bco 2) and circadian rhythm(cipc). To summarize, our study provides some information on the genetic structure and diversity of Japanese koi and Chinese FFRC carp. Furthermore, based on the data obtained on relevant genes related to skin color differentiation and pigmentation, it can provide a theoretical basis for the subsequent integration of dominant traits and precision breeding in carps. • Compared to that of FFRC carp, the genetic diversity of koi carp is relatively lower. • There is a significant population differentiation between FFRC and koi. • GWAS analysis identified genes associated with body color differentiation including ephrinB 2, oca 2 and bcmo 1. [ABSTRACT FROM AUTHOR]

Emerging pathogen, carp edema virus (CEV) causes koi sleepy disease (KSD) in Koi and common carp causing severe mortalities worldwide. In the present study, a total of 150 fish species belonging to eight different families were sampled from the ornamental fish retailers and farms, located in Karnataka, India. The OIE protocol viz., level-I, II and III diagnoses confirmed the infection of CEV in 10 koi fish. Interestingly, other fish species belonging to different fish family including cyprinidae family were negative to CEV. Further, CEV infection was confirmed by sequencing (partial 4a gene); it showed the similarity with that of CEV reported from India and Germany strains with similarity of 97.4–99.94% and belonged to genogroup IIa. TEM analysis of purified CEV, in vivo cohabitation and tissue infection experiments confirmed the CEV infection. In addition, viral load was significantly higher (106−7 copies) in koi collected from Dakshina Kannada than of Bengaluru (103−4 copies). To understand the host–pathogen interaction, different organs such as gill, kidney, liver and spleen from naturally (CEV) infected koi were used to study the immune gene responses by using eight innate and one adaptive immune response. Results indicated that TNF-α, RohTNF-α, iNOS, IFN-γ and IL-10, and catalyze β-2M of MHC class I pathway genes were upregulated in koi. Higher expression of immune genes during the CEV infection may have inhibited viral replication and mount an antigenic adaptive response. Similar to other viral infections, interferon-γ play an important role during poxvirus infections. Quantification of immune genes in infected fish will provide insights into the host responses and provide valuable information to devise intervention strategies to prevent and control disease due to CEV. • Ornamental fish species were screened for CEV, only ten koi were found to be positive. • TEM analysis and in vivo experiments confirmed the CEV infection. • Viral load was high in koi from Dakshina Kannada followed by Bengaluru. • Upregulation of immune genes such as TNF-α, RohTNF-α, iNOS, IFN-γ and IL-10 in koi. [ABSTRACT FROM AUTHOR]

Plant polyphenol supplementation may improve fish health in aquaculture systems. To assess the potential benefits and function mechanism of plant polyphenols in aquaculture, fish were fed either basal feed (CON) or the basal feed supplemented with 500 mg/kg of curcumin (CUR), oligomeric proanthocyanidins (OPC), chlorogenic acid (CGA), or resveratrol (RES). After an 8-week feeding experiment, blood samples were used to analyze the concentrations of biochemical indices. Gut samples were collected to evaluate microbiota, short chain fatty acid (SCFA) levels, and gene expression. The results indicated that polyphenol administration reduced serum glucose and insulin. Lysozyme activity was enhanced by OPC and CGA, and superoxide dismutase activity was increased by CUR, OPC, and CGA. The gut microbial structure of the RES group was segregated from that of the CON, and the genus Bacteroides was identified as a potential biomarker in the CUR, CGA, and RES groups. Total gut SCFA increased in the CUR, CGA, and RES groups. A strong correlation was observed between Bacteroides and SCFA. In conclusion, dietary polyphenols have distinct anti-inflammatory, anti-oxidant, and anti-hyperglycemic activities that may be closely associated with their microbiota-modulation effects. [ABSTRACT FROM AUTHOR]

Galectins are β-galactoside sugar binding proteins which function as important pattern recognition receptors (PRRs) in innate immunity. Here, we identified a galectin-9 gene from koi carp (Cyprinus carpio), named kGal-9. The ORF of kGal-9 is 963 bp in length, which encodes a polypeptide of 320 amino acids without either signal peptide. The predicted molecular weight is 36.25 kDa, and the isoelectric point is 8.3. Multiple sequence alignment showed that the putative kGal-9 contains two carbohydrate recognition domains (CRD), which are conserved in Galectin-9s. The phylogenetic tree showed that kGal-9 clustered to Galectin-9s from other teleosts, and shared the highest identity of 87.5% with Qihe crucian (Carassius auratus). kGal- 9 mRNA was abundant in head kidney, gills, and gut, but low in liver and muscle. Further, the expression level of kGal-9 in the head kidney and liver increased significantly after Aeromonas veronii (abbreviated A.v) infection. Unexpectedly, kGal-9 showed a remarkable downregulation in the spleen at various time points post A.v infection. Intramuscular injection of pckGal-9 not merely reduced the bacterial load of spleen tissue, but also improved the survival rate of koi carp post A.v challenge. Besides, administration of pckGal-9 stimulated the expression of several immuno-related genes including proinflammatory cytokines (IL-1β , IL-6), anti-inflammatory cytokine (IL-10), complement components (C4 , C9), with fluctuation in spleen and head kidney. Taken together, the obtained results suggest that kGal-9 occupies an important role in innate immunity and defense against bacterial infection in koi carp. • Galectin-9 was characterized in koi carp, and the eukaryotic expression plasmid pckGal-9 was constructed. • kGal-9 was abundant in head kidney, gill, and intestine and up-regulated in head kidney and liver by bacteria A.v infection. • IAdministration of pckGal-9 reduced the splenic bacterial load, but also improved the survival rate of koi post A.v challenge. • Injection of pckGal-9 stimulated the expression of IL-1β, IL -6, IL -10, C4, C9 , with fluctuation in spleen and head kidney. [ABSTRACT FROM AUTHOR]

Since the end of the1990ies, Cyprinid herpesvirus 3 (also known as koi herpesvirus, KHV) has caused mass mortality events of koi and common carp all over the globe. This induced a high economic impact, since the KHV disease cannot be cured up to now, but only prevented by vaccination. Unfortunately, there is only one commercial vaccine available which is not approved in most countries. Therefore, there is an urgent need for new, safe and available vaccines. In this study, a live attenuated vaccine virus was generated by cell culture passages of virulent KHV, and shown to protect carp or koi after immersion or oral application against wild type challenge. An advantage of boost immunization was demonstrated, especially after oral application. Vaccination induced no or mild clinical signs and protecting antibodies have been measured. Additionally, the vaccine virus allowed differentiation of infected from vaccinated animals (DIVA) by PCR. The attenuation of the newly generated vaccine was tracked down to a partial deletion of open reading frame 150. This was confirmed by the generation of engineered ORF150 deletion mutants of wild-type KHV which exhibited a similar attenuation in vivo. [ABSTRACT FROM AUTHOR]

Economic importance of common carp (Cyprinus carpio L.) increases every year. Viral diseases are major threat for carp aquaculture and cause significant economic losses. Koi herpesvirus (KHV) is one of the most serious carp diseases. Current study is focused on confirmation of possible differences in early immune response to KHV depending on level of resistance. Class I interferon signalling, complement cascade and cell-mediated cytotoxicity are hypothesized as major mechanisms of early innate immune response against KHV. Different breeds of common carp show distinct level of resistance to KHV. Two breeds of common carp with completely different susceptibility to KHV were chosen for current research: amur wild carp (AS) as highly resistant and koi carp (KOI) as very susceptible breed. KHV infection caused no mortalities, but the viral load in selected tissues increased during infection. Levels of expressions of chosen genes was examined using qRT-PCR and overall change in protein expression profiles was analysed by mass spectrometry. Significant differences in immune response between AS and KOI were detected mostly at the level of protein expression. Although cell-mediated cytotoxicity showed minimal influence during KHV infection, many immune response parameters related to class I interferon signalling pathway and complement cascade were increased earlier during KHV infection in AS comparing to KOI. • Viral load increased significantly in susceptible carp, but not in resistant carp. • Activation of class I interferon signalling pathway was faster in resistant carp. • Complement cascade was triggered during koi herpesvirus infection at protein level. [ABSTRACT FROM AUTHOR]

Quality evaluation of koi (Cyprinus rubrofuscus) is essential to the koi industry. However, the community has a lack of knowledge about the quality evaluation of koi and about features of koi which are valuable. During the "All Japan Nishikigoi Show" competition, a quality evaluation of koi was conducted by authoritative experts. In the present study, photos of participants of this competition were used for analysis to discover features affecting the quality of the Kohaku variety of koi. The HSVA color model was used to define and extract from image red and pale red coverage rates in Kohaku body coloration. Body aspect ratio, body proportions, red coverage rate, and pale red coverage rate were extracted using tools written in Python programming language. Analyses of the extracted data revealed the significant impact body aspect ratio (p < 0.001) and pale red coverage rate (p < 0.001) on Kohaku quality. A low body aspect ratio has a positive impact on Kohaku quality, while a high pale red coverage rate has a very strong negative impact on Kohaku quality. This study and its results can be an important foundation for further research about koi quality. [ABSTRACT FROM AUTHOR]

Aims: To investigate the gut microbiota communities of reciprocal hybrids and inbred lines of koi (Cyprinus carpio) and goldfish (Carassius auratus), as well as the genetic effect of intestinal microbiota between hybrids and parents. Methods and Results: The reciprocal hybrids and inbred lines derived from the parents, koi and goldfish, were established. Then, the bacterial 16S rRNA gene of intestinal contents was sequenced using Illumina Miseq PE300. Alpha diversity in the two types of hybrids was lower than inbred lines of koi or goldfish and was highest in goldfish, followed by koi. For beta diversity, microbial samples presented clear clusters and the two types of hybrids were more similar to koi than goldfish, indicating the gut microbiota of the reciprocal hybrids was more affected by koi. The dominant phyla were Proteobacteria, Actinobacteria and Firmicutes in koi, and Proteobacteria, Fusobacteria and Actinobacteria in goldfish, and Proteobacteria, Fusobacteria and Firmicutes in the reciprocal hybrids. In the case of Proteobacteria, the dominant classes were Alphaproteobacteria and Gammaproteobacteria in four fish. The dominant genera were norank_f_Rhizobiales_Incertae_Sedis and Plesiomonas in koi, Cetobacterium in goldfish, and Cetobacterium and ZOR0006 in the reciprocal hybrids. PICRUSt1 predictive function analysis showed that the reciprocal hybrids had lower abundance in the most functional categories than koi and goldfish. Conclusions: The gut microbiota of reciprocal hybrids was more affected by koi. Two types of hybrids possessed the same dominated phyla and were different from the inbred lines of koi and goldfish. Significance and Impact of the Study: It enhanced our understanding of gut microbiota of hybrid lines of goldfish and koi and provided a new perspective for the selective breeding of gut microbiota traits. [ABSTRACT FROM AUTHOR]

This study reports the occurrence of cyprinid herpesvirus 3 (CyHV‐3) in koi carp (Cyprinus carpio koi) for the first time in India. The koi carp, with clinical signs of ulcer with haemorrhage on body surface, necrosis of fin and discolouration of gill associated with huge mortality, were observed in aquarium shops, rearing tanks and grow‐out ponds located in Chennai, India. The PCR assay carried out on infected fish samples using different primer sets specific to CyHV‐3 confirmed its presence in the infected fish. Sequence analysis of partial thymidine kinase gene revealed 100% similarity with the sequence of CyHV‐3 available in GenBank. Cell lines of koi carp and catla were found to be susceptible to CyHV‐3 and its replication was confirmed by viral‐specific cytopathic effect, PCR and bioassay. The CyHV‐3 infection was reproduced by intramuscular injection of inoculum prepared from CyHV‐3‐infected fish to satisfy Koch's postulates. Tissue tropism of CyHV‐3 in infected fish by PCR assay revealed the presence of CyHV‐3 in all vital organs with prominent band in gill and gut tissue. [ABSTRACT FROM AUTHOR]

Carp edema virus (CEV) is the causative agent of koi sleepy disease (KSD), a serious gill disease affecting common carp, Cyprinus carpio, and its ornamental variety, koi. After recent detections of the virus in various countries around the world, KSD has emerged as a new global disease in carp. However, the prevalence of the infection in carp populations in a given geographical region has not been studied thoroughly. The present communication reports an investigation into the presence of CEV in carp and koi populations in Germany. For this purpose, gill samples collected from carp and koi populations suffering from gill diseases or collected for a routine examination of their health status were tested for the presence of CEV by PCR. In total, 651 fish samples from 401 carp or koi cases were examined in 2015 and 2016, additional 118 samples from previous studies were included in the examination. CEV was detected in archive samples from carp dating back to 2007, and in koi samples dating back to 2009. From 2015 to 2016, CEV was detected in 69% of cases from carp populations examined from the main carp‐producing areas in Germany, and in 41% of the examined cases from koi populations from all over Germany. Clinical KSD occurred mainly from April to June in carp populations at water temperatures ranging from 8 to 12°C and in koi populations at water temperatures ranging from 18 to 22°C. Most fish from clinically affected carp or koi populations harboured high virus loads of above 10,000 copies of CEV‐specific DNA per 250 ng DNA, while gills from fish of other fish species from the ponds, including goldfish, grass carp and European perch were found CEV negative or harboured a low virus load. A phylogenetic analysis revealed the presence of multiple CEV variants from genogroup I in carp and genogroup II in koi populations in Germany. Genetically identical genogroup I isolates were detected in carp from different geographical locations in Germany and in other European carp populations. Some German genogroup II variants were identical to variants previously recorded from koi in Asian and other European countries. The data presented here show that CEV is highly prevalent in German common carp and koi populations and implies the spreading of this virus by intense trading of common carp and koi without necessary risk mitigating measures. As infections with this virus may induce serious disease, CEV diagnostic should be included in health surveillance and disease monitoring programmes. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Desert Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dermocystidiosis in common carp (Cyprinus carpio L.) as a skin infection in the form of small, pea‐sized bulging nodules is well‐known in Hungary. Its occurrence is sporadic, and the pathogenic effect is generally moderate. Nonetheless, here we report an unusual case of the infection when a mass of dermocystid spore‐filled hyphae‐like cysts formed a large tumour‐like nodule under the skin intruding deeply in the red muscle on one side occipital region of the fish body. Histological sections showed that the tumour‐like nodule was composed of two layers, a pale peripheral part with a high mass of cysts surrounded by some cell debris of muscle cells and a dark central part with a less dense meshwork of tubular cysts which were embedded in the partially damaged red muscle tissue. No infection was found in the white muscle. Sequences of 18S rDNA of spores from the tumour‐like nodule showed a complete identity to sequences from typical bulging nodules in skin. They were also highly similar to the sequences of D. anguillae clones (99.5%–99.4%), to some samples of D. salmonis (99.7% and 99.4%), and to the Dermocystidium sp. CM‐2002 (99.4%) from European perch. [ABSTRACT FROM AUTHOR]

Domestication is a process in which animals are bred in captivity under controlled resource availability. Compared with wild-type phenotypes, animals with domesticated phenotypes exhibit reduced stress sensitivity and cognitive abilities. The pigmentation of domesticated phenotype animals is a morphological change, one of those that is considered a "domestication syndrome". In fish, the impact of pigmentation on behaviour and physiology has rarely been examined. We compared the performance of two phenotypes of the common carp Cyprinus carpio : a wild-coloured phenotype and an orange-coloured phenotype of koi carp. The fish were exposed to short-term stress conditions, after which blood samples were collected to obtain biochemical indices. The maze and field experiments were used to observe individuals' movement activity, exploratory behaviour, and ability to find food in the experimental maze. The fish were equipped with radio tags for the field experiment. In the riverine environment, movement activity and preferred temperatures during light/dark cycles were observed. Presuming that the orange-coloured carp exhibit reduced cognitive ability, we hypothesized that they would exhibit i) reduced exploratory behaviour and ii) lower stress sensitivity than wild-coloured carp. Our results revealed mostly nocturnal activity in koi carp. The koi carp needed more time to explore the maze, as expected, but contrary to our assumption they showed greater stress levels accompanied by greater movement activity. This behaviour was similar for different maze setting. The wild-coloured carp were active during both day and night and exhibited greater left-sided lateralization and cognitive skills, allowing them to find food faster. For the wild-coloured phenotype, body temperature was significantly correlated with all the other observed variables. Our results suggest potentially lower welfare of the koi carp in mixed aquaculture, e.g., a lower ability to use feeding resources than the wild-coloured carp. [Display omitted] • Behavioural and physiological traits differed between coloured carp phenotypes. • Wild-coloured carp explored the environment more effectively. • Behaviour of the wild-coloured phenotype correlated with a proactive coping style. • Koi phenotype showed higher sensitivity to stress and mostly nocturnal activity. • Mixing of coloured fish may reduce the welfare of phenotypes sensitive to stress. [ABSTRACT FROM AUTHOR]

The koi carp is an ornamental fish that was obtained through artificial selection from the common carp (Cyprinus carpio L.). The most economically important traits of koi are their beautiful skin patterns in bright colors. As seasonality is an important factor in the biology and ecology of fish, we thus assumed that seasonal changes are involved in regulating the formation of skin color and patterns of koi carp. The white, red, cyan, and black skin colors from four varieties of scaleless koi carp (Doitsu Shiromuji (W), Doitsu Kohaku (W R), Doitsu Showa Sanke (WRI), and Kumonryu (WI)) were evaluated using the CIELab color space (lightness, redness, and yellowness) in different seasons. Compared to winter, the yellowness of the white color in all koi varieties decreased in summer and autumn. The black skin color areas in WRI and WI koi increased in summer and autumn compared to winter. The yellowness of the red color decreased only in WRI koi, while no changes were observed in W R koi. Targeted metabolomics analysis revealed that the levels of the structural pigment guanine of all koi varieties showed significant seasonal variation. Of seven detected carotenoids, the zeaxanthin and tunaxanthin contents in W, WI, and WRI koi changed with the seasons, while none of the carotenoids in W R koi were altered. Of the seven potential regulatory metabolites, epinephrine, melatonin, and cyclic adenosine monophosphate (cAMP) in all four koi varieties showed the highest levels in winter. A correlation analysis suggested that the seasonal changes in white skin color occurred through the epinephrine-cAMP pathway; melanin-dependent and carotenoid-dependent skin color changes occurred through melatonin in koi carp. This study demonstrated the seasonal plasticity of skin color in koi carp regulated by melatonin and epinephrine, associating with variety and color specificity. [Display omitted] • Koi variety differences in seasonal skin color plasticity. • Components of seasonal variation in carotenoids are zeaxanthin and tunaxanthin. • Seasonality changes the red skin of koi through melatonin. • Seasonality changes the white skin of koi through epinephrine-cAMP pathway. [ABSTRACT FROM AUTHOR]

Koi , Y. , Watanabe , A. , Kawasaki , A. , Ideo , S. , Matsutani , N. , Miyashita , K. , Shioi , S. , Tokunaga , E. , Shimokawa , M. , Nakatsu , Y. , Kuraoka , I. , Oda , S. Mutation spectra of the BRCA1/2 genes in human breast and ovarian cancer and germline. Environmental and Molecular Mutagenesis. 2024 ; 65 : 179 – 186.The gray shading in Table 1 that denotes analyses with an insufficient number of data (as noted in the table footnote) was missing in the original publication. It has been corrected and republished.We apologize for these errors. [Extracted from the article]

Klebsiella michiganensis is emerging as an important human pathogen of concern especially strains with plasmid-mediated carbapenemase genes. The IncX3- bla NDM-5 plasmid has been described as the primary vector for bla NDM-5 dissemination. However, whether strains with this plasmid have any competitive edge remain largely unexplored. We characterized a bla NDM-5-producing Klebsiella michiganensis strain (KO_408) from Japan and sought to understand the driving force behind the recent dissemination of IncX3- bl aNDM-5 plasmids in different bacterial hosts. Antibiotic susceptibility testing, conjugation, and whole-genome sequencing were performed for KO_408, a clinical isolate recovered from a respiratory culture. Fitness, stability, and competitive assays were performed using the IncX3- bla NDM-5 plasmid, pKO_4-NDM-5. KO_408 was ascribed to a novel sequence type, ST256, and harbored resistance genes conforming to its MDR phenotype. The bla NDM-5 gene was localized on the ~44.9 kb IncX3 plasmid (pKO_4-NDM-5), which was transferable in the conjugal assay. The acquisition of pKO_4-NDM-5 did not impose any fitness burden and showed high stability in the host cells. However, transformants with pKO_4-NDM-5 were outcompeted by their host cells and transconjugants with the IncX3- bla OXA-181 plasmid. The genetic environment of bla NDM-5 in pKO_4-NDM-5 has been previously described. pKO_4-NDM-5 showed a close phylogenetic distance with seven similar plasmids from China. KO_408 clustered with strains within the KoI phylogroup, which is closely associated with carbapenemase genes. This study highlights the emergence of a high-risk Klebsiella michiganensis clone harboring carbapenemase genes and affirms that the recent spread of IncX3- bla NDM-5 plasmids might be due to their low fitness cost and stability but not their competitive prowess. [ABSTRACT FROM AUTHOR]

A ten-week feeding trial was performed to evaluate the effects of chlorogenic acid (CGA) on the growth, body color, antioxidant activity, serum biochemical parameters, and immune response of koi. Five diets were formulated to contain 0 (control), 200 (CGA-2), 400 (CGA-4), 600 (CGA-6), and 800 (CGA-8) mg/kg CGA for the rearing of experimental fish. By means of an analysis by polynomial orthogonal contrasts, it was determined that dietary supplementation with CGA had no significant effects on the growth performance of koi (P > 0.05), while body color indices (redness, yellowness, and lightness) showed a linear order polynomial (P < 0.05). A quadratic response was found for the relationship between total carotenoid in scale of koi and dietary CGA levels, with an optimum level of 381.84 mg/kg. Dietary CGA levels and lysozyme activity showed a cubic relationship polynomial model, with an optimum level of 383.89-975.73 mg/kg. TGF-β expression in the head-kidney of koi was obviously improved by 600 mg/kg CGA diet (P < 0.05). And in regards to effect in serum, SOD and CAT activities was best explicated by a linear order polynomial, while the quadratic and cubic relationship polynomial models represented the GSH and GSH-Px activities, which the optimal supplementation level of CGA was estimated at 550.78 and 231.74-782.66 mg/kg, respectively. The relationship between ALT activity and CGA supplementation was best explicated by quadratic relationship polynomial, with an optimum level of 522.78 mg/kg. Based on the model observed, 522.78-600 mg/kg CGA was the recommended supplementation in diet that improved the body color, antioxidant activity, biochemical parameters, and immune response of koi. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Tikrit University for Humanities is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background. Myxosporean diversity is a hot topic since they are difficult to accurately identify and classify. Many Myxobolus parasites have been named as Myxobolus koi because of their similar morphological features with the species originally reported. However, the distinctions in fine morphological features, host specificity, and molecular data have given rise to the attention of researchers. Methods. The classical morphometric and histological methods were used to describe the Myxobolus dajiangensis n. sp. in morphology. The common techniques in modern molecular biology and the methods of phylogenetic analyses were combined to identify the species. Results. Plasmodia of interlamellar-vascular type were found in the vascular network of gill lamellae. Mature myxospores of M. dajiangensis n. sp. were elongated and pyriform from the frontal view. The myxospores were 14.8 ± 0.4 (13.9-15.6) mm in length, 8.0 ± 0.5 (7.2-9.1) mm in width, and 5.5 mm in thickness. The two polar capsules were pyriform and slightly different in length. The length of the larger polar capsules was 8.0 ± 0.4 (7.1-8.8) mm, and it was 7.4 ± 0.4 (6.1-8.0) mm for the smaller ones. The width of both polar capsules was 2.5 ± 0.2 (2.0-3.2) mm. The polar filaments within the polar capsules were each coiled nine to 11 turns. Comparative analysis of both the morphological and molecular data between the present speices and other similar species revealed that the present species is a novel species, Myxobolus dajiangensis n. sp. Also, M. koi (FJ710800) was misidentified and the congener with M. dajiangensis n. sp., depending on the secondary structures of SSU rRNA and phylogenetic analysis. Moreover, the cryptic species existed in the M. koi parasites. [ABSTRACT FROM AUTHOR]

The increasing number of Koi ornamental fish interested around the world, this fish farming business is increasingly developing. Blitar is one of the geographically suitable areas to develop Koi fish farming. The resulting production has a quality of Koi better than from other countries. Cultivation models and techniques developed are also increasingly advanced, but often cultivators have disease problems stemming from decreasing environmental quality that are not handled early. This attracted the Brawijaya University Doctoral community service team to help find solutions to these problems.

Klebsiella michiganensis is emerging as an important human pathogen of concern especially strains with plasmid-mediated carbapenemase genes. The IncX3-blaNDM-5 plasmid has been described as the primary vector for blaNDM-5 dissemination. However, whether strains with this plasmid have any competitive edge remain largely unexplored. We characterized a blaNDM-5-producing Klebsiella michiganensis strain (KO_408) from Japan and sought to understand the driving force behind the recent dissemination of IncX3-blaNDM-5 plasmids in different bacterial hosts. Antibiotic susceptibility testing, conjugation, and whole-genome sequencing were performed for KO_408, a clinical isolate recovered from a respiratory culture. Fitness, stability, and competitive assays were performed using the IncX3-blaNDM-5 plasmid, pKO_4-NDM-5. KO_408 was ascribed to a novel sequence type, ST256, and harbored resistance genes conforming to its MDR phenotype. The blaNDM-5 gene was localized on the ~44.9 kb IncX3 plasmid (pKO_4-NDM-5), which was transferable in the conjugal assay. The acquisition of pKO_4-NDM-5 did not impose any fitness burden and showed high stability in the host cells. However, transformants with pKO_4-NDM-5 were outcompeted by their host cells and transconjugants with the IncX3-blaOXA-181 plasmid. The genetic environment of blaNDM-5 in pKO_4-NDM-5 has been previously described. pKO_4-NDM-5 showed a close phylogenetic distance with seven similar plasmids from China. KO_408 clustered with strains within the KoI phylogroup, which is closely associated with carbapenemase genes. This study highlights the emergence of a high-risk Klebsiella michiganensis clone harboring carbapenemase genes and affirms that the recent spread of IncX3-blaNDM-5 plasmids might be due to their low fitness cost and stability but not their competitive prowess.

Acyclovir inhibits CyHV-3 replication in a dose-dependent manner. The viral load in the CyHV-3-infected, ACV-treated group was divided by the viral load in CyHV-3-infected control and the outcomes were expressed as a percent of the control. Contrary to Troszok et al., (2018) that suggested 66.67 µM as a maximal safe concentration of ACV, Quijano Cardé et al. (2020) showed that even 1500 µM of ACV was safe for the koi carp fin (KF1) cell line. [Extracted from the article]

Fish are frequently anesthetized to reduce stress and injury during various procedures, particularly surgery. Nonetheless, the majority of chemical fish anesthetics have some negative effects on both fish and humans. 2-Phenoxyethanol (2-PE), for example, which is normally used as an anesthetic for ornamental fish, can cause neuropsychological syndromes in humans. To reduce toxicity, some herbal essential oils have been applied as an anesthetic to fish. However, essential oils must be dissolved in ethanol, which has side effects such as disrupting gas exchange in fish. This study aimed to develop mugwort (Artemisia vulgaris) oil as a nanoemulsion without ethanol and determine their optimal concentrations to use as an anesthetic for surgery on koi carp (Cyprinus carpio). Gas chromatography-mass spectrometry (GC/MS) was used to examine the chemical compositions of mugwort oil. The droplet size of mugwort oil nanoemulsion was measured by the dynamic light scattering method. The results revealed that mugwort oil consisted of three major active compounds which were b-pinene (11.7%), 1,8-cineole (10.34%), and a-pinene (8.29%). The average diameter of mugwort oil nanoemulsion droplets was 22.08 ± 0.70 nm. The lowest effective concentrations were 0.6 ml/L for mugwort oil and 12.5 ml/L for mugwort oil nanoemulsion. [ABSTRACT FROM AUTHOR]

Information on growth dynamics of koi grown long-term in recirculating aquaculture systems (RAS) is lacking. The objective of this study was to establish baseline parameters for an older (i.e. not larval or juvenile) population of koi grown in a commercial RAS. A population of 1033 1.5-year-old koi (6 g to 764 g) cultured in a 60 m3 commercial decoupled aquaponics system with cannabis were graded into distinct size cohorts (six cohorts, from "very small" to "very large"), and their growth and population distributions were monitored over 66 days. Fish were weighed at day 0, day 36, and day 66. Feed conversion ratios and specific growth rates were between 2.8–4.1 and 0.63–0.87, respectively, and increased and decreased with fish size, respectively. Regardless of average initial weight or cohort size, several individuals in each tank vastly outgrew the rest of the population, resulting in right-skewed population distributions. Right-tail asymmetry (skewness) of the population distributions became more pronounced for all cohorts, except the largest cohort. Similarly, kurtosis (the relative number and extremity of outliers compared to a normal distribution) increased in all cohorts. These results suggest that the production of "tobi koi" or "shoot carp" is not restricted to larval and juvenile koi populations, and that if size disparity cannot be eliminated through husbandry practices (e.g. minimizing feed competition), populations should be graded 2–3 times yearly to promote growth and welfare of the smallest fish in a cohort. [ABSTRACT FROM AUTHOR]

In the aquaculture industry, an efficient and safe water purification system is important to prevent mass mortality by virulent pathogens. As extensive use of traditional methods (e.g.: povidone-iodine, ozone, ultraviolet irradiation, formalin, and chlorine dioxide) have adverse effects on cultured fish, an appropriate and alternative water purification method is vital for the sustainability of the industry. Non-thermal plasma technology has been successfully used for various biomedical purposes (e.g: food sterilization, medical device disinfection, wound healing, cancer therapy, etc.) and has great potential to be used as a sterilizing system. However, few studies have been conducted on its usefulness in the aquaculture industry. In this study, we investigated the bactericidal efficacy of plasma-activated water induced by non-thermal plasma and its histopathological as well as immunological adverse effects on koi. A highly virulent Aeromonas hydrophila SNU HS7, which caused massive mortality of koi, was used for this study. Non-thermal plasma was applied for 10 min to the fish tanks with 1.2 × 109 CFU/mL SNU HS7 using PLMB-20 system to confirm the sterilization efficacy and to observe the survival and immunological reaction of koi for 14 days. As a result, gross pathological, histopathological, and immunological investigations did not reveal any significant adverse effects in fish as compared to the control groups. To the best of our knowledge, this is the first study showing that non-thermal plasma can be used for sterilization of rearing water without giving significant physiological damage to the fish, even under the assumption of extreme situations. As plasma can effectively sterilize not only bacteria but also other unknown pathogens, the results of this study are showing a promising future in purifying water in aquaculture practice. • Highly virulent A. hydrophila SNU HS7, toxic to koi, was isolated and identified. • Non-thermal plasma treatment shows excellent bactericidal efficacy. • First study to show–sterilization is possible without significant physiological damage to fish. • Applying plasma to aquaculture can prevent diseases caused by unknown pathogens. [ABSTRACT FROM AUTHOR]

The need for yield research is increasing with the popularity of aquaponic food production systems where plants and fish are grown together in a recirculating system. Our objective was to compare the yield of three basil cultivars ("Elenora," "Genovese," "Nufar," Ocimum basilicum) in four configurations (greenhouses: floating raft DWS, ebb & flow, A‐frame; warehouse: floating raft; 1–8 tank replications/treatment) as well as a soilless control to establish a baseline for aquaponic producers in northern latitudes. We also tested whether basil yield varied among fish types: yellow perch, Perca flavescens, goldfish, Carassius auratus, tilapia, Oreochromis spp., and koi, Cyprinus carpio. Fish tank water temperature, nitrite, and alkalinity levels differed significantly over seasons (summer, winter). There was a significant decrease in basil production in all aquaponic systems that used koi (greenhouse, warehouse). No significant difference in basil yield was found among greenhouse and aquaponic systems for perch, tilapia, or goldfish nor among the basil "Elenora," "Genovese," and "Nufar." Considerable variation occurred in yield although most of it occurred in fresh weights, being reduced significantly in dry weights. The effects of growing koi fish on reducing aquaponic production of basil is noteworthy, although future research is needed to the exact cause. [ABSTRACT FROM AUTHOR]

To maximize profits from aquaponic system, a high-price 'koi' carp (Cyprinus carpio) produced at Sultan Qaboos University was used. This study consisted of two experiments. The first experiment aimed to determine the optimal stocking density of 'koi' carp in an aquaponic system. In the second experiment, the optimal density of 'koi' carp based on the first experiment was used in combination with tomato, eggplant, and mint as a control from the first experiment. The aquaponic system consisted of 9 pairs of glass tanks; in each pair water was recirculating with the use of a submersible pump. In the first experiment, 'koi' carp fry (0.4-0.5 g each) were stocked at 50, 100 and 150 individuals per tank (0.1 m3) in combination with mint and the ornamental plant Petunia. Fish were stocked in tanks with and without plants. Results show that 'koi' carp stocked at 100 per tank without plants had significantly better growth (mean final weight of 7.5 g from the initial weight of 0.4-0.5 g). Fish stocked in tanks with plants, 'koi' carp at 50 per tank had significantly better growth (mean final fish weight of 5.2 g from the initial weight of 0.4-0.5 g). Survival rate was highest at 50 per tank with or without plants. Mint growth was better in tanks with 50 fish per tank. Petunia had flowers in all treatments. Water quality parameters were within optimal range even at high fish stocking densities. Overall, stocking density of 50 fish per tank can be recommended based on survival data. In the second experiment, 30 'koi' carp juveniles were stocked in all tanks without plants (i.e. 6.5 g, 5.5 g and 6.1 g respectively) for each treatment in combination with mint, tomato, and eggplant. Growth and survival rates of koi (30 fish per tank) in combination with mint, eggplant and tomato were high with a weight gain of 21.3, 17.6, 17.6 g and survival rate of 90%, 95.5% and 87.8%, respectively. The results showed that 'koi' can be successfully grown with different plants in an aquaponic system. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study themacronutrient profilingof high valued indigenous freshwater fishes of West Bengal. Eleven high valued freshwater finishes, viz. Folui (Notopterusnotopterus), Belle (Glossogobiusgiuris), Koi (Anabas testudineus), Mourala (Amblypharyngodonmicrolepis), Punti (Puntiuschola), Cuchia (Monopterus cuchia), Pabda (Ompok pabda), Kailipabda (Ompok bimaculatus), Tengra (Mystus vittatus), Chanda (Parambassis ranga) and Nandus (Nandus nandus) were collected from local market of West Bengal to determine their nutritive valuethrough proximate and major mineral composition of flesh. The proximate and major mineral composition of these fishes like protein, lipid, moisture, ash and carbohydrate as well as calcium and potassium were estimated by standard methods. The average moisture content ranged from 70.20 to 79.70%. The flesh crude protein content ranged between 14.79% to 20.44%with the highest protein was found in Ompok bimaculatus and lowest in Puntius chola.The lipid content varied widely from 1.94 to 4.28%, with Ompok bimaculatus being the fattiestflesh (4.28 %). Other nutrients, such as ash content werevarying from 0.96% to 2.31%. The Calcium contents were 0.02 to 0.06% and the Phosphorous contents were 0.05 to 0.20% as well.So,in the present study, it could be concluded that these fishes are the source of quality protein and minerals, thereby safeguarding both nutritional and livelihood security for protein hunger. [ABSTRACT FROM AUTHOR]

A 60 days experiment was conducted to evaluate the effect of marigold (Tagetes erecta) leaf meal as natural carotenoid for koi carp (Cyprinus carpio L.) fingerlings. Fishes with an average weight of 2.0 g were fed one of the six diets prepared for this study as follows: Diet 1 (T0) without marigold, Diet 2 (T1) – Basal diet + 11%, Diet 3 (T2) – Basal diet + 13%, Diet 4 (T3) – Basal diet + 15%, Diet 5 (T4) – Basal diet + 17%, Diet 6 (T5) – Basal diet + 19% marigold flower leaf meal, respectively. The experimental koi carp were fed at the rate of 3% body weight. Significantly difference at (p<0.05). In growth parameters highest in as weight gain (3.600 ± 0.057 g) in T3, percent weight gain (35.465± 0.468) in T3, specific growth rate (0.506 ± 0.005) in T3, gross conversion efficiency (0.158 ± 0.001) T3, length gain (0.78 cm) in T3 and the lowest value of feed conversion ratio was reported (6.308 ± 0.061) in T3 as maximum feed utilization. At the end of research period the maximum coloration was recorded in T4 with L, A & B value {(17.470± 0.060), (1.820± 0.081), (5.010 ± 0.121)} respectively and lowest L, A & B value. The findings of current research indicate that dietary use of graded marigold flower meal at the rate of 15gm/ 100gm diet has a beneficial impact on growth performance and 17g/100g of diet can enhance the coloration of koi carp fingerling. [ABSTRACT FROM AUTHOR]

This study used an experimental approach to compare the passage success of native and exotic fish species from the temperate Southern Hemisphere over an artificial baffled fish ramp designed for overcoming low‐head (≤1.0 m) fish migration barriers. Passage efficiency was, on average, lower for the exotic species [koi carp (Cyprinus carpio), rudd (Scardinius erythrophthalmus) and rainbow trout (Oncorhynchus mykiss)] compared to the native species [inanga (Galaxias maculatus), redfin bully (Gobiomorphus huttoni) and common bully (Gobiomorphus cotidianus)]. Nonetheless, there was considerable variation between individual species, with rainbow trout outperforming common bully and juvenile inanga, but koi carp and rudd failing to pass any of the ramps. The differences in predicted probability of passage success between the native and exotic fish species in this study were sufficient in some cases to indicate the potential for the baffled fish ramps to operate as a selective migration barrier. Nonetheless, further testing is required to validate these results across a broader range of conditions before deployment. [ABSTRACT FROM AUTHOR]

Gills of fish are involved in respiration, excretion and osmoregulation. Due to numerous interactions between these processes, branchial diseases have serious implications on fish health. Here, "koi sleepy disease" (KSD), caused by carp edema virus (CEV) infection was used to study physiological, immunological and metabolic consequences of a gill disease in fish. A metabolome analysis shows that the moderately hypoxic-tolerant carp can compensate the respiratory compromise related to this infection by various adaptations in their metabolism. Instead, the disease is accompanied by a massive disturbance of the osmotic balance with hyponatremia as low as 71.65 mmol L−1, and an accumulation of ammonia in circulatory blood causing a hyperammonemia as high as 1123.24 µmol L−1. At water conditions with increased ambient salt, the hydro-mineral balance and the ammonia excretion were restored. Importantly, both hyponatremia and hyperammonemia in KSD-affected carp can be linked to an immunosuppression leading to a four-fold drop in the number of white blood cells, and significant downregulation of cd4, tcr a2 and igm expression in gills, which can be evaded by increasing the ion concentration in water. This shows that the complex host-pathogen interactions within the gills can have immunosuppressive consequences, which have not previously been addressed in fish. Furthermore, it makes the CEV infection of carp a powerful model for studying interdependent pathological and immunological effects of a branchial disease in fish. [ABSTRACT FROM AUTHOR]

The current study evaluated the efficiency of three forms of dietary sodium propionate (SP) on growth performance, digestive and liver antioxidant enzymes activities, as well as skin mucus immune responses of koi carp (Cyprinus carpio koi) fingerlings. Gelatine micro and nanoparticles loaded with SP were synthetized and expressed as gelatine‐SP MPs and gelatine‐SP NPs, respectively. Basal diet was supplemented with gelatine microparticles, gelatine nanoparticles, powder‐SP, gelatine‐SP MPs and gelatine‐SP NPs. Fish were distributed into 18 experimental units and fed with prepared diets for eight weeks. The results indicated that the growth performance improved in fish fed SP‐supplemented diets in comparison with the controls. The highest growth performance was observed in gelatine‐SP NPs followed by gelatine‐SP MPs. The digestive enzymes activity including protease, trypsin, lipase and α‐amylase in gelatine‐encapsulated SP micro and nanoparticles dietary groups increased significantly in comparison with other dietary groups (p <.05). The use of SP‐loaded micro and nanoparticles decreased the liver alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in comparison to other groups (p <.05). Feeding fish with SP‐supplemented diets led to increasing antioxidant enzymes of superoxide dismutase (SOD), glutathione (GSH) and catalase (CAT), as well as alkaline phosphatase (ALP) in the liver tissue in comparison to the controls (p <.05). The skin mucus lysozyme, alternative haemolytic complement activity (ACH50) and total immunoglobulin (Ig) levels were higher in SP‐dietary groups than the controls; the highest levels were in gelatine‐SP NPs dietary group (p <.05). The findings confirmed that the administration of SP loaded into micro and nanoparticles of gelatine could improve its efficiency in the diet of koi fish. [ABSTRACT FROM AUTHOR]

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Adult koi carp (Cyprinus carpio L.) were fed with feed supplemented with vitamin C at 200 mg/kg feed (T1), 400 mg/kg feed (T2) and 600 mg/kg feed (T3), and vitamin E at 200 mg/kg feed (T4), 400 mg/kg feed (T5) and 600 mg/kg feed (T6) at ad libitum for 60 days. Control (without vitamin inclusion) was also maintained. Observations were made on the growth performance, GSI and biochemical composition of gonads such as crude protein, crude fat, cholesterol and carotenoid once in 15 days. At the end of the experiment, fertilization was done to record the fertilization and hatching rate. The difference in the values was noticed among the male and female koi carp. Fish supplemented with vitamin E at 200 mg/kg feeexhibited higher growth in both male and female fish, and the fertilization rate and hatching rate were also higher in that group, and the values were significantly different (p < 0.05) and showed linear and quadratic trends. Inclusion of vitamin C at 600 mg/kg feed had shown higher lipid and carotenoid contents of female koi carp (p<0.05). Hence, the results revealed that supplementing vitamin C and E in the diet is necessary for the successful reproduction of koi carp. [ABSTRACT FROM AUTHOR]

The koi sleepy disease of carp caused by the carp oedema virus (CEV) was observed on farms and in ponds in France since the 2010s. Samples of CEV collected in France over a period of eight years were characterized at the molecular level by sequencing the partial p4a gene. All the sequences, except one, fell into two well‐defined genogroups. Sequences obtained from CEV detected in common carp generally clustered in genogroup I and sequences from CEV detected in the koi were assigned to genogroup II. A particular sample was different to the others and represented a putative new genogroup possibly arose from a recombination event between a genogroup II sequence and one from an unknown genogroup. Compared with sequences from CEV of other countries, most of the French sequences exhibited high degree of DNA identities with those published previously, indicating identical sources of viruses. The sequence diversity suggests multiple introductions of the viruses in France. Among the French sequences, two genogroup‐specific molecular markers were identified. One was an insertion/deletion identified within a microsatellite and other was a group of single nucleotide polymorphisms. CEV seems to generate genetic diversity via diverse mechanisms: substitutions, indels and recombination events. [ABSTRACT FROM AUTHOR]

The prime Kepler mission detected 34,032 transit-like signals, out of which 8054 were identified as likely due to astrophysical planet transits or eclipsing binaries. We manually examined 306 of the remaining 25,978 detections, and found six plausible transiting or eclipsing objects, five of which are plausible planet candidates (PCs), and one stellar companion. One of our new PCs is a possible new second planet in the KOI 4302 system. Another new PC is a possible new planet around the KOI 4246, and when combined with a different possible planet rescued by the False Positive Working Group, we find that KOI 4246 may be a previously unrecognized three-planet system. [ABSTRACT FROM AUTHOR]

Carp edema virus (CEV), a poxvirus from the family Poxviridae, was first detected in 1974 in Japan and has since spread to most parts of the world. CEV is the etiological agent of koi sleepy disease (KSD), which has adverse health effects on both koi and common carp fish species. Equally, KSD leads to detrimental financial distress to carp farmers and further threatens both food security and ecology. The onset and severity of CEV/KSD is influenced by water temperature and handling stress. The prominent clinical sign of KSD in both koi and common carp is lethargy, which is manifested when the water temperature is in the range of 15 - 25 °C and 6 - 9 °C, respectively. Much advancement is needed to curb the spread of CEV. Since the early years of CEV, the immersion of diseased fish into a 0.5% salt-water solution has been shown to be efficacious in treating the clinical signs but ineffective in eradicating the virus in infected fish. Therefore, infected asymptomatic fish become CEV carriers. This is further exacerbated by the limited knowledge of the transmission pathways of CEV. This paper aims to collate the current knowledge on CEV/KSD, to give an insight into the nature and characteristics of CEV. [ABSTRACT FROM AUTHOR]

In this study, the delimitation of intestine segments of koi carp (Cyprinus carpio var. koi) was conducted using a histological approach with the measurements of height of mucosa folds (HF), width of mucosa folds (WF), thickness of muscularis (TM) and cross‐sectional area (CSA). According to the change trends for these four parameters, the intestine of the koi carp was divided into anterior intestine, middle intestine and posterior intestine. The locations of the three intestine segments were defined, and their ratios along the entire intestine were accounted for 23.84 ± 1.18%, 46.77 ± 2.29% and 29.39 ± 1.65%, respectively. The anterior intestine had a significantly higher HF, compared with the middle (p <.01) or posterior intestines (p <.01). The muscularis became thin gradually from the anterior intestine to posterior part. TM was significantly different among the anterior, middle and posterior intestines (p <.01). The anterior intestine had a significantly higher CSA, compared with the middle (p <.01) and posterior intestines (p <.01), and the latter two segments had similar CSA values (p >.05). The procedure of the delimitation of the koi carp intestine segments can offer useful information for future studies on other fish species. The presented results are meaningful for studies on differential functions of the different intestine segments in fish. [ABSTRACT FROM AUTHOR]

This research aims to study the ability of Aloe vera (Burm.f.), extract to treat Koi fry [Cyprinus rubrofuscus (Lacépède, 1803)] which is attacked by Aeromonas hydrophila (Chester, 1901). The method used was the experimental method using a completely randomized design with five treatments and three replications was applied. The treatment used was immersion with A. vera extract with a concentration of treatment A (0 mg kg-1), B (150 mg kg-1), C (300 mg kg-1), D (450 mg kg-1) and E (600 mg kg-1). The variables observed were in vitro test, LC50-24-h test, clinical symptoms which included damage to fish body, fish feeding response and fish response to shock which were analyzed descriptively comparatively. The results showed A. vera extract has the ability as an antibacterial with inhibition zone diameter reaching 20.49 mm at a concentration of 5 000 mg kg-1 and LC50 test 48 h (in vivo test) of 1 157.16 mg kg-1, so for the treatment of fish use concentrations below that concentration. The use of aloe vera extract with a concentration of 300 mg kg-1 for 48 h was effective to treat koi fry infected with A. hydrophila by healing relatively fast body damage, response to feed and shock is normal and fast. [ABSTRACT FROM AUTHOR]

Koi herpesvirus (KHV) is a highly contagious virus that causes KHV disease (KHVD) inducing high mortality in carp and koi (Cyprinus carpio L.). In the late stage, latency occurs with very low, often non‐detectable virus concentrations, which represents a challenge for virus detection. After validation according to OIE recommendations, an antibody ELISA was established to recognize antibodies of C. carpio against KHV infection. In this study, the ELISA was modified to detect anti‐KHV antibodies from a non‐cyprinid fish. Experimentally infected rainbow trout (Oncorhynchusmykiss) were able to transmit KHV to naïve carp at two different temperatures, demonstrating their potential as a reservoir host. At 20°C, KHVD was induced in carp but not at 15°C. Unexpectedly, rainbow trout developed humoral response against KHV at both temperatures. In contrast to carp, at 15°C trout produced neutralizing antibodies but not at 20°C. While antibodies obtained from infected carp sera reacted in a similar way against all KHV, antibodies from rainbow trout sera reacted differently to the same isolates by ELISA. The data show that even when non‐cyprinid fish species are infected with KHV, they can produce antibodies that differ from those observed in carp. [ABSTRACT FROM AUTHOR]

The quality and safety of the aquatic products have gradually become the focus of global attention. In this study, the environmental eukaryotic and fungi communities in pond-cultured grass carp (Ctenopharyngodon idellus) and the koi carp (Cyprinus carpio L.) were investigated. For comparative analysis, the alpha diversity shows that the environmental microbial abundance in the koi carp groups were higher than that in the grass carp groups, while beta diversity reveals that the differences of the microbial community composition and structures in the grass carp groups were significantly higher than those in the koi carp groups. Meanwhile, the environmental microbial diversity of grass carp groups was higher than that of koi carp groups at phylum level, but showed no significant difference at genus level. Additionally, the dominant total phyla were Opisthokonta, Stramenopiles plusAlveolates plusRhizaria, Archaeplastida, Cryptophyceae, and Centrohelida for the 18S rRNA gene and Ciliophora, Chlorophyta, and Ascomycota for the ITS2 rRNA gene in both of the two carp groups. Additionally, annotation analysis showed that the biomarkers in the grass carp groups are significantly higher than those of the koi carp groups. Furthermore, the functional prediction of Funguild showed significant difference in outputs, while similarity in trophic modes and guild types between the two carp groups. Meanwhile, the total relative abundances of animal pathogen, fungal parasite, and plant pathogen were extremely similar between the two carp groups. Surprisingly, one pathogenic fungus of genus Fusarium was identified in both the environments of two carp groups based on filtered operational taxonomic unit tables. Overall, this is the first robust report to understand the characteristics of environmental eukaryotic microorganisms and fungi in the edible and ornamental carps. Our results also provide the basic data for the prevention of fungal diseases and the healthy culture of the carps. [ABSTRACT FROM AUTHOR]

The present research aims to evaluate the impact of both dietary vitamin E and dietary sage supplementation on growth performance of koi carp fingerlings, reared in a partial recirculating aquaculture system. Koi carp specimens with an average individual biomass of 5.1 ± 0.4 g were equally distributed, as follows: V1 - diet supplemented with 1% vitamin E (V1), respectively, V2 - diet supplemented with 1% sage. A 5% BW (Body weight) daily feeding ratio was applied. During the 49 days trial, individual biomass measurements were performed at initial, after 8, 15, 25 and 37 days, as well as at the final stage of the experiment. The specific growth rate indicates a superior fish production at V2 (3.30%BW/day), compared to V1 (2.75%BW/day). Also, better FCR values are recorded at V2 (1.28), compared to V1 (1.62). The Protein efficiency ratio (PER) results indicate a better ability of V2 koi carp specimens to utilize proteins (1.39), compared to V1 specimens (1.10). Thus, dietary supplementation with 1% sage has a superior effect on growth performance of koi carp fingerlings, compared to 1% vitamin E dietary supplementation. [ABSTRACT FROM AUTHOR]

Koi herpesvirus (KHV) is highly contagious and lethal to cyprinid fish, causing significant economic losses to the carp aquaculture industry, particularly to koi carp breeders. Vaccines delivered through intramuscular needle injection or gene gun are not suitable for mass vaccination of carp. So, the development of cost-effective oral vaccines that are easily applicable at a farm level is highly desirable. In this study, we utilized chitosan-alginate capsules as an oral delivery system for a live probiotic (Lactobacillus rhamnosus) vaccine, pYG-KHV-ORF81/LR CIQ249, expressing KHV ORF81 protein. The tolerance of the encapsulated recombinant Lactobacillus to various digestive environments and the ability of the probiotic strain to colonize the intestine of carp was tested. The immunogenicity and the protective efficacy of the encapsulated probiotic vaccine was evaluated by determining IgM levels, lymphocyte proliferation, expression of immune-related genes, and viral challenge to vaccinated fish. It was clear that the chitosan-alginate capsules protected the probiotic vaccine effectively against extreme digestive environments, and a significant level (P < 0.01) of antigen-specific IgM with KHV-neutralizing activity was detected, which provided a protection rate of ca. 85% for koi carp against KHV challenge. The strategy of using chitosan-alginate capsules to deliver probiotic vaccines is easily applicable for mass oral vaccination of fish. [ABSTRACT FROM AUTHOR]