Search

This study analyzes the species composition, length–weight relationship (LWR), condition factor, and morphometric and meristic characteristics of eleven freshwater fish species in Kota Panjang Reservoir, Indonesia. Fresh specimens were collected from September 2023 to February 2024. Results show that among the sampled species, two belong to Order Anabantiformes, three to Order Siluriformes, and six to Order Cypriniformes. The Order Siluriformes has the lowest species composition, with Hemibagrus wyckii at 3.09%, while the Order Cypriniformes has the highest, with Barbonymus schwanefeldii at 15.25%. The LWR coefficient b ranges from 1.693 to 3.151. Of the species studied, only Hemisilurus heterorhynchus (b = 2.174), Clarias teijsmanni (b = 2.046), Anabas testudineus (b = 2.375), Labiobarbus festivus (b = 2.305), and Rasbora argyrotaenia (b = 1.693) fall outside the expected range of 2.5 < b less than < 3.5. One species exhibits a positive allometric growth (+), seven show a negative allometric growth (−), and three display an isometric growth (I). Fulton's condition factor (Kc) averages between 0.73 ± 0.15 and 4.96 ± 0.63, indicating morphological variation. The allometric condition factor (Ka) ranges from 0.87 ± 0.18 to 26.25 ± 4.05, reflecting differences in resource availability and competition. Relative condition factor (Kn) values range from 1.00 ± 0.09 to 2.51 ± 0.55, indicating good growth. Morphometric analysis shows that Rasbora argyrotaenia has the smallest average total length, head length, and body depth, while Hemibagrus wyckii has the largest. The results provide new data on the LWR, condition factor, and morphometric characteristics of eleven selected freshwater fish species in Kota Panjang Reservoir, Indonesia, and offer up‐to‐date information on the remaining species in the study area. These findings could have a significant impact on species stock assessments and help identify priority species for domestication. [ABSTRACT FROM AUTHOR]

A study was conducted to compare the high-density rearing of stinging catfish (Heteropneustes fossilis) fingerlings in both a control system and a biofloc system over 100 days. In the biofloc system, probiotics and a carbon source were added, while the control group had no additions. The biofloc system showed significantly (p < .05) higher floc volume (8.34 ± 1.33 ml L−1) and improvements in growth performance, survival rate, and biomass yield. Fingerlings reared in the biofloc system had increased digestive, oxidative enzyme activities and a lower feed conversion ratio. No changes were observed in the whole-body proximate composition between the groups. However, nonspecific immune responses, such as lysozyme and myeloperoxidase, were relatively improved, and other immune parameters like respiratory burst activity and total serum immunoglobulin were significantly increased in the biofloc system. In conclusion, biofloc-based rearing significantly enhanced the growth performance, feed utilization, and immunological conditions of stinging catfish. [ABSTRACT FROM AUTHOR]

Research focusing specifically on people who have been catfished online, or deceived in some way, but maybe not defrauded out of money is relatively scarce. The current study sought to add to the literature in this area by surveying social media and dating application users about their catfishing victimization experiences (n=1,511). Fourty-four percent had been catfished in the last 5 years. Common characteristics of those who had been catfished include the catfish reaching out first, a short duration of communication, and asking for money, among other characteristics. The lifestyles/routine activities (LRAT) framework and self-control were utilized to examine potential risk factors for catfishing victimization. Both online and offline behaviors were found to influence catfishing risk, suggesting the LRAT can be applied to this type of victimization. Implications for policy application and prevention of catfishing fraud are discussed. [ABSTRACT FROM AUTHOR]

The present study was conducted to select Streptomyces strains that exhibited characteristics of probiotics for application in aquaculture. Streptomyces were isolated from soil and sediment samples collected from various habitats such as riverside, shrimp ponds, pangasius ponds, mangrove forests, or estuaries along the coast of Vietnam. Two strains of Streptomyces (AG12.2 and ND10.1) were selected due to (1) their potent antimicrobial activity against common pathogens that cause serious diseases in shrimp and pangasius such as E. ictaluri, A. hydophila, V. harveyi, V. parahaemolyticus, and (2) their superior ability to produce several extracellular enzymes that strongly hydrolyze organic compounds such as starch, CMC, and skimmed milk, compared to other strains. AG12.2 and ND10.1 can tolerate salinity from 0 ppt to 5 ppt and pH from 3 to 8; however, their growth is most vigorous at salt concentrations and pH between 0 ppt to 2 ppt, and 7.2 to 8, respectively. In vivo evaluation on L. vannamei in this study shows that shrimp that were fed with diets containing AG12.2 and ND10.1 had WG (%) increasing by 1.59 times and 1.61 times respectively, DGW (g/day) increasing by 1.64 times, and FCR decreasing by 1.30 times and 1.35 times respectively. The shrimp treated with AG12.2 and ND10.1 were then challenged with V. parahaemolyticus, resulting in a survival rate increase of 3.9 times and 3.71 times, respectively. Phylogenetic analysis revealed that strains AG12.2 and ND10.1 belong to Streptomyces kunmingensis and Streptomyces angustmyceticus, respectively. The findings of the present study led to the conclusion that Streptomyces kunmingensis AG12.2 and Streptomyces angustmyceticus ND10.1 are excellent candidates for producing beneficial probiotics for aquaculture. [ABSTRACT FROM AUTHOR]

The impact of dietary fenugreek (FN) supplementation on growth performance, physio‐metabolic enzyme response, and antioxidant enzyme activities in hybrid African catfish (Clarias gariepinus ♀ × Heterobranchus bidorsalis ♂) was investigated in this study. Five isonitrogenous diets (38% crude protein) were developed and fed to the fish for 60 days. The FN was incorporated into the diets at 0%, 0.5%, 1.0%, 1.5%, and 2%. Two hundred twenty‐five fingerlings of hybrid African catfish (average weight 4.01 g ± 0.02) were used for the study and randomly distributed to five dietary groups in triplicate. FN supplementation improved growth responses and survival rates; the dietary groups considerably (p < 0.05) outperformed the control group. FN‐based diets considerably increased the carcass protein content (p = 0.020) and improved protein retention (p = 0.015). FN supplementation markedly (p < 0.001) and dose‐dependently reduced the carcass's lipid content and substantially (p < 0.001) increased the levels of metabolic enzymes. The fish antioxidant capacity was significantly enhanced (p < 0.001), and hepatic stress enzymes were greatly (p < 0.001) lowered in FN‐based diets. In summary, the second‐order polynomial regression analysis indicates that the optimal dose of FN supplementation to improve hybrid catfish growth without negatively affecting the fish's physio‐metabolic response or overall wellbeing is 1% dietary inclusion level. [ABSTRACT FROM AUTHOR]

Glyptothorax pongoensis, sp. n. is described from the Yongmon River in Nagaland, India. The new species can be distinguished from its congeners in the Indian subcontinent by the following combination of characters: an ovate-shaped thoracic adhesive apparatus with skin ridges present over the entire apparatus, including the subulate-shaped median depression; presence of plicae on the ventral surface of the pectoral fin spine and the first ray of the pelvic fin; W-shaped anterior nuchal plate element; dorsal-fin origin nearer to the snout tip than to the origin of the adipose fin; posterior margin of dorsal spine rugose with 4–5 ridges, tuberculate skin, and nasal barbel not reaching eye when adpressed. [ABSTRACT FROM AUTHOR]

The current study tested the hypothesis that an increase in the ionic levels (Na+, Cl--, Ca2+, Mg2+, and K+) in the gastrointestinal tract (GIT), and hepatosomatic index (HSI), gonadosomatic index (GSI), and Fulton's condition factor (FCF) are associated with the reproduction period of silver catfish (Rhamdia quelen). So, we verified ionic levels of the fluid phase of the different portions of the GIT content, HSI, GSI, and FCF of silver catfish in different seasons in a dam in southern Brazil. The highest Na+ and Cl-- levels in GIT were found in spring. The stomach's Na+ and Cl-- values were lower than the other segments. The K+ and Ca2+ levels in GIT were higher in winter, except in the stomach, where the values increased in summer. The highest K+ levels were reported in the anterior intestine. The highest Ca2+ levels in winter and spring were reported in the anterior and mid-intestines. In summer, the Mg2+ levels in the intestine were lower. The values of GSI and FCF were higher in winter and spring, and those of HSI were higher in winter. In conclusion, ions in the GIT and HSI, GSI, and FCF were higher in the reproduction period (winter for spring). [ABSTRACT FROM AUTHOR]

A variety of bionic vacuum suckers with papillae structures of different parameters were developed to improve the attachment performance of vacuum suckers. The oral sucker of the suckermouth catfish served as the bionic prototype and bionic suckers were made by taking the diameter of papillae, the number of single rows of papillae, the center distance between adjacent rows of papillae, and the distance between the outermost row of papillae and the edge as influencing factors. The single-factor tests and response surface tests were carried out respectively with the growth rates of vertical and horizontal attachment forces as the response values. Twenty-five groups of bionic suckers and one group of standard suckers were fabricated and tested for attachment forces. The experimental results revealed that the bionic suckers had higher vertical and horizontal attachment forces than standard suckers and that their maximum growth rates for these forces were 5.16% and 59.87%, respectively. This suggested that the bionic suckers had better attachment performance. The significant orders of the factors affecting response values were established and their interaction was also analyzed. Besides, the optimal parameter combination of papillae structures of the bionic suckers with optimal vertical and horizontal attachment properties was obtained, respectively. Finally, the influence mechanism of papillae structures on the attachment properties of bionic suckers was analyzed. The studies can serve as a guide for the application of bionic suckers in agricultural production areas such as fruit picking and handling, and the improvement of attachment performance of associated machinery. [ABSTRACT FROM AUTHOR]

The banjo catfish, Xyliphius barbatus, belongs to the Aspredinidae family and typically inhabits the main channels of medium to large rivers in the La Plata River basin. The mimetic coloration with the substrate and the benthic lifestyle likely contribute to the challenge of sampling this species, resulting in its underrepresentation in museums and ichthyological collections. In fact, the original description of X. barbatus was based solely on two specimens. Consequently, little is known about its osteology, distribution, and phylogenetic relations. In this work, these information gaps are filled and the distributional range for X. barbatus is extended to northwestern Argentina. [ABSTRACT FROM AUTHOR]

This work provides new molecular data on seven species representing three genera (Protoancylodiscoides, Schilbetrema and Synodontella) in the order Dactylogyridea. The results help to explain the origin of Synodontella spp. and to elucidate the phylogenetic position of Synodontella in relation to the other genera. The findings also highlight the importance of the haptoral elements in determing phylogenetic relationships between and within Dactylogyridea taxa, which are monogenean parasites of mostly cyprinid fishes in fresh water. A total of 36 catfish specimens representing five species in three genera (Synodontis, Schilbe and Chrysichthys) were collected from two rivers in Cameroon: the Sanaga River (at Edéa and Nachtigal, in the Littoral and Cental regions, respectively) and Boumba River (at Mang-kaka, East Region), and examined for gill parasites. The novel 28S rDNA sequences of seven species belonging to Dactylogyridea were obtained and their phylogenetic relationships inferred. Synodontella resulted as a monophyletic lineage; the samples obtained from the catfish in Cameroon were well-differentiated into two groups. Synodontella appears to be more closely related to Schilbetrema than to the other Dactylogyridea species investigated here. The shape of the ventral bar should be considered an important feature for distinguishing among Dactylogyridea genera. The existence of two or more lineages within the genus Synodontella, as suggested by previous morphological studies, is here molecularly confirmed, indicating speciation as likely an outcome of ecological influences or the phylogenetic relationships among parasites and/or hosts. [ABSTRACT FROM AUTHOR]

Homology is the foundation of any comparative evolutionary study, and as structures previously considered homologous are found to be convergent, and vice versa, terminology needs to be changed to reflect homology. The dorsal- and pectoral fin-spines of catfishes (order Siluriformes) are morphologically diverse and ornamentations adorning the anterior and posterior edges of the spines have regularly been used in systematic studies of the group. Building on Vanscoy et al. (2015), Kubicek et al. (2019) showed that some of the ornamentations of siluriform fin-spines previously considered homologous result from two different developmental pathways, and presented a terminology based on the homology of these structures. In their recent paper, Ballen and de Pinna (2021) proposed a new terminology for various catfish fin-spine structures, including fin-spine ornamentation. However, homology was not considered and, instead, their terminology is based on the general shape of the ornamentation to allow for 'unambiguous use' in various applications, including the placement of fossil fin-spines into well-defined clades of catfishes. We show that the terminology proposed by Ballen and de Pinna (2021) is problematic as it confuses non-homologous conditions into the same state and thus undermines the usefulness of fin-spine ornamentation as a character in comparative evolutionary studies of siluriforms. [ABSTRACT FROM AUTHOR]

Burn injury remains a health problem, specifically in Indonesia. In major burns, xenograft has been proved to be useful as temporary wound coverage. However, some xenografts are not widely available due to cultural, financial and religious backgrounds, or have an unesthetic appearance, such as the scaly appearance of tilapia fish xenograft.Striped catfish (Pangasius hypophthalmus) is a scaleless fish that has abundant type 1 collagen. This study aimed to compare striped catfish skin to commonly used xenograft (Nile tilapia and porcine skin) as xenograft material for burn wound. In this experimental study, nine different skin samples of striped catfish, Nile tilapia and porcine were prepared and histologically examined using hematoxylin-eosin stained samples. Macroscopic and microscopic features of each sample were documented and analysed. The macroscopic skin appearances of striped catfish were hairless and scaleless with black-silver color and moderate thickness. As for microscopic features, the epidermal thickness of striped catfish skin (8.49±1.60 μm) was significantly different to both Nile tilapia (2.18±0.37 μm; p<0.001) and porcine skin (42.22±14.85 μm; p=0.002). The dermal thickness of striped catfish skin (288.46±119.04 μm) was similar to Nile tilapia (210.68±46.62 μm; p=0.783) but differs significantly to porcine skin (1708.44±505.12 μm; p<0.001). The integrity and collagen organization of striped catfish was also similar to tilapia based on semi-quantitative histology scoring system (p>0.05). Striped catfish had potential macroscopic appearance and comparable microscopic features to Nile tilapia; smoother macroscopic appearance, thicker epidermis, and similar dermis thickness. Therefore, we believe it can be potentially used as a xenograft material. Further studies are required to evaluate the effectiveness and feasibility of striped catfish xenograft in burn wound management. [ABSTRACT FROM AUTHOR]

Pimelodidae is a family of large‐sized catfishes consisting of 116 valid species divided into 30 genera distributed in the Neotropical region. Despite recent advancements in understanding the pimelodid phylogeny, several internal relationships have remained unclear and have received limited support from various phylogenetic analyses. We provide a new genomic dataset comprising 55 species representing 25 genera of Pimelodidae and related siluriform families Aspredinidae, Auchenipteridae, Cetopsidae, Doradidae, Diplomystidae, Heptapteridae, Loricariidae, and Pseudopimelodidae. Our phylogenetic analyses support the monophyly of Pimelodidae, as well as the existence of four major lineages: the Steindachneridion clade, the Leiarius + Phractocephalus clade, and two major subclades herein classified as Sorubiminae and Pimelodinae. Our topology resolves Phractocephalus sister to Leiarius differing from previous phylogenies. In Sorubiminae, Zungaro is sister to two large clades: one with Sorubim, Sorubimichthys, and Pseudoplatystoma, and the other with Hemisorubim, Platysilurus, Platystomatichthys, Brachyplatystoma, and Hypophthalmus. In Pimelodinae, we found the Pimelodus ornatus clade, the calophysines, and the clade with Exallodontus, Propimelodus, and Pimelodus altissimus closer to the Pimelodus group. Parapimelodus, Duopalatinus, Iheringichthys, and Bergiaria are included within the Pimelodus group. The Pimelodus group contains four main components: (1) Duopalatinus peruanus, (2) the trans‐Andean Pimelodus grosskopfii; (3) Pimelodus maculatus clade with species from the Brazilian Shield in southeastern Brazil; and (4) Pimelodus blochii clade composed by species from the Amazon, Orinoco, Paraná‐Paraguay, Parnaíba, São Francisco and coastal drainages of the Guiana Shield. The P. maculatus clade is composed by phenotypically diverse species, and the P. blochii clade houses species morphologically similar that appear nested within the widely distributed P. blochii. [ABSTRACT FROM AUTHOR]

To face the current downward trajectory of freshwater biodiversity loss, the implementation of effective biodiversity monitoring programs is of utmost importance. Environmental DNA offers unprecedented opportunities for this aim but several challenges still need to be addressed before implementing efficient species monitoring using eDNA. One of them is optimizing the eDNA sampling scheme to maximize the eDNA detection probability. For instance, in flowing freshwaters, the transport of eDNA downstream from its source can impact the eDNA detection probability, and blur the link between eDNA detection and the local occurrence of the species. Here, we investigated the eDNA spatial range of Harttiella lucifer (Siluriformes, Loricariidae), a threatened neotropical siluriform fish inhabiting French Guianese mountain streams, and confined to waterfalls and fast‐flowing environments. Environmental samples were collected at 11 sites from the H. lucifer population to 2000 m downstream. A species‐specific dPCR approach was applied to quantify the amount of DNA present in each sample and evaluate the eDNA detection probability of H. lucifer according to the distance from its source. Results showed an accumulation of eDNA at 50 and 100 m downstream from H. lucifer population. The evaluation of detection probabilities revealed that 300 m downstream from H. lucifer population, the probability of detection drops to 50%. This study suggests that eDNA drift in neotropical small streams is limited to a few tens meters downstream. These findings demonstrate that in neotropical small streams, eDNA provides a picture of the local fish fauna rather than integrating information over large spatial scales. [ABSTRACT FROM AUTHOR]

Hardhead catfish (Ariopsis felis) are one of two Ariidae catfishes in the northern Gulf of Mexico and are one of the most common fishes found in the coastal waters in this region. As a generalist consumer with a unique reproductive life history and limited information on long-term population dynamics in the Western Gulf of Mexico, the objectives of this study were to assess trends in Texas estuaries using long-term fishery independent and dependent data sets and to conduct habitat suitability analyses in these same estuaries for both young-of-the-year and adult hardhead catfish. Some estuaries have experienced decreasing trends in catch-per-unit-effort (CPUE) of adult hardhead catfish beginning in the mid-1990s and early 2000s, and widespread decreasing trends in adult mean length were additionally observed for central and lower coast estuaries. Compared to the CPUE of finfish in the larger community, adult hardhead catfish largely exhibited decreasing trends in their relative contribution (expressed as percentage of CPUE) across most Texas estuaries. When combined with the larger Ariidae species grouping, and compared to the relative contribution of common Sciaenids, it was generally observed that the contributions of these two species groupings were converging for many estuaries. This was primarily characterized by increasing Ariidae trends. Given the trophic role of Ariidae catfishes, they clearly have the potential to exert major trophic influence on estuarine food webs. Our study highlights the value of long-term monitoring and the study of non-gamefish species in the larger assessment of community change across time. [ABSTRACT FROM AUTHOR]

Purpose: Studies on monogeneans parasitizing representatives of Siluriformes in Africa remain scarce and fragmentary. In order to contribute to fill this gap, we screened Heterobranchus longifilis from the Lindi River in the Democratic Republic of the Congo. Methods: Heterobranchus longifilis was purchased from fishermen in DR Congo, province of Tshopo, in Kisangani town, the Lindi River. The monogeneans were individually isolated from the gill and transferred directly onto a slide in a drop of Hoyer's medium. Results: Quadriacanthus lindiensis n. sp. is morphologically similar to Quadriacanthus longifilisi. However, it is distinguished from the latter by its non-sclerotized vagina, its dorsal cunei shape and the size of its bars. Conclusion: Only Q. lindiensis n. sp. was found on the gills of the single individual of H. longifilis screened. In the future, a representative sampling should enable us to verify if Q. lindiensis n. sp. co-occurs with other species known to parasitize H. longifilis. [ABSTRACT FROM AUTHOR]

As nutrient-rich water in aquaponic systems cannot supply growing plants with all the required trace elements, supplementation with specific fertilizers is performed to make up for this deficit. While chelated fertilizers such as ethylenediaminetetraacetic acid-zinc disodium complex (Zn-EDTA) are becoming more popular in this context for improving plant growth in aquaponic systems, little is known about their effects on fish. During two experiments, a total of 576 individuals of catfish fry (0.19 g) and fingerlings (220.01 g) of the African catfish (Clarias gariepinus; Burchell, 1822) were kept separately for 32 days under experimental aquarium conditions. The fry was exposed to 0.125 and 0.5 mg/L, while the fingerlings were exposed to 0.5 and 2.0 mg/L Zn-EDTA in a plantless aquaponic system. The third treatment group consisted of a control group without Zn-EDTA. The growth, mortality, and ethological indicators were assessed for all growth stages, while the leukocyte distribution and histopathological changes were additionally determined for the fingerlings. As the feed intake in the experiment was limited, the investigations were focused on the effects of Zn-EDTA and not on the growth process of a respective fish growth stage. While the growth, mortality, and behavior were not significantly different in both growing stages, the number of mature neutrophils changed significantly in all treatments in fingerlings. Zn was not detected in the histologically investigated organs at the tested concentrations using the staining method. However, morphological alterations of the gill epithelium were found on the secondary lamellae. Quantitative multiplex PCR was used to simultaneously evaluate the expression of 17 genes related to Zn metabolism and stress physiology in head kidney samples. The transcripts of several selected genes changed by up to 70-fold. Due to high individual variances, only the copy numbers of the KMT2A (lysinespecific methyltransferase 2a) gene were significantly different across treatment groups and sampling points. However, the present results indicate that the addition of Zn-EDTA at the tested concentrations can be considered relatively benign for the health and welfare of C. gariepinus, as no toxic effects of Zn-EDTAwere observed in moderately hard to hard water. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to analyze the physiological properties, pathogenicity and application of probiotic bacteria to catfish (Clarias sp.) cultivation in vivo. Methodology and results: Probiotic bacteria's physiological characteristics were described using descriptive approaches, whereas experimental methods analyzed pathogenicity tests and the application of the probiotic bacteria in catfish cultivation. The results of bacterial characterization showed that Bacillus safensis strain C251 SA3, Bacillus amyloliquefaciens strain NO10 SA8 and Bacillus australimaris strain IIHR GAPB01 SL1 had bacili cell shape and showed a positive catalase test for all test bacteria except Bacillus safensis strain C251 SA3. The three probiotic bacteria also had negative oxidative-fermentative results, which were able to reduce nitrate and survive in environmental conditions with pH 3-9. Pathogenicity analysis revealed that the three bacteria had the potential to be non-pathogenic or less pathogenic. Bacillus safensis strain C251 SA3 treatment on catfish resulted in the best survival rate of 64% and a 17.5 cm growth in catfish body length by week 13. When Bacillus amyloliquefaciens strain NO10 SA8 was applied to catfish, the survival rate was 32% and the catfish body length increased by 22 cm by week 13. The control treatment revealed that all catfish samples died or had a 0% survival rate, while the application of Bacillus australimaris strain IIHR GAPB01 SL1 revealed a catfish survival rate of 0%. Conclusion, significance and impact of study: Bacillus australimaris strain IIHR GAPB01 SL1 is a potential probiotic bacterium to be applied in catfish food. [ABSTRACT FROM AUTHOR]

The article discusses research which demonstrated the first record of armored catfish Pterygoplichthys pardalis, a native belonging to the Loricariidae family, from the North Himalayan region on River Tawi in India. The study describes the morphometric and meristic characteristics of Pterygoplichthys pardalis, including snout, dorsal, pectoral, pelvic and anal spines, caudal peduncle, pectoral and pelvic base, and dorsal, pectoral, pelvic, anal and caudal fin rays.

The bristlenose pleco (Ancistrus cirrhosus) is a species of Loricariidae armored catfish that breathes air using its highly vascularized stomach when faced with hypoxic aquatic environments. The main goals of this study were to determine the developmental onset of air breathing and air-breathing behavior in A. cirrhosus from juveniles to adults. Developing juveniles reach functional maturity within 4 to 6 months of hatching, growing to an adult length of 8 to 10 cm. To examine the timing of the developmental onset of air breathing, we tested for air-breathing behavior in juveniles beginning at 1 cm in length up through adults at 8 cm in length by exposing each fish to an acute gradual decrease in aquatic oxygen content from 100% air saturation down to 8% air saturation over a 50-min period. Juvenile fish first began to breathe air at body lengths between 2.1 and 3 cm and masses of 1.1 and 2 g. Fish with body lengths above 3 cm all breathed air when hypoxia challenged. In fish that breathed air, there was a weak negative correlation between fish length and % air saturation at which air breathing began. Fish were also exposed to an acute bout of 15% air saturation for 60 min, and breathing behavior was observed. Fish exposed to 60 min acute 15% air saturation exhibited a negative correlation between the frequency of air breathing and fish length. The developing A. cirrhosus can take advantage of the aerial environment once they reach 3 cm in length and 2 g when exposed to aquatic hypoxia. Prior to this size, these animals would potentially succumb to severe aquatic hypoxia without the ability to breathe air. [ABSTRACT FROM AUTHOR]

Fish gut is a versatile organ serving as the primary pathway for invasion by pathogens, particularly parasites, playing a crucial role in modulating the intestinal adaptive immune response. This study aimed to investigate the cellular-mediated reaction, mucosal acidity, and the expression of proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), and CD68 in the intestines of catfish, Clarias gariepinus, naturally infected with helminths. Forty catfish were collected from the Nile River and examined for intestinal parasites. The intestinal tissues of the control and infected fish were fixed for histochemical and immunohistochemical studies. Two groups of helminths were found: cestodes Tetracampos ciliotheca and Polyonchobothrium clarias, and nematodes Paracamallanus cyathopharynx, with a prevalence rate of 63.63%, 18.0%, and 18.0%, respectively. Our results showed that the infected fish had a statistically significant rise in the activity of immune cells, including mast cells, eosinophil granular cells, and dendritic cells. This correlated with upregulation in the expressions of PCNA, VEGF, and CD68. Histochemical analyses demonstrated a marked increase in acidic mucus production, Sudan black B, and bromophenol mercury blue. This study enriches our understanding of the evolution of vertebrate immunity in combating intestinal parasitic infections and the host's adaptive responses. [ABSTRACT FROM AUTHOR]

Nano-sized Zn particles are recognized for its ability to elevate fish health and well-being, enhancing antimicrobial and antioxidant capacities and reinforcing the immune system. In the present study we explored the effects of Zn-NPs supplementation on augmenting the growth performance and nutritional indicators and physiological aspects of the catfish, Clarias batrachus. Zn-NPs were prepared by heating the mixture of [Zn(CH3COO)2.2H2O], ethylene glycol and polymer surfactant (PVP) at 70°C for 45  min using an oil bath heater. The resultant solution was centrifuged at 6000  rpm on a heated plate at 70°C until the precipitation of Zn-NPs was achieved. Crystal structure, growth mechanisms and shapes of Zn-NPs were characterized by the atomic force microscopy. Produced Zn-NPs was characterized by spectrophotometer and the zeta potential and mean size was recorded as −32.5  ±  1.0  mV and 14.7  ±  2.5  nm, respectively. The experiment comprised six distinct test diets, categorized by the incorporation of Zn-NPs at levels of 0, 10, 20, 30, 40, and 50  mg/kg into the feed where the initial diet was employed as a control group, devoid of any Zn-NPs supplementation. Three glass aquariums were employed for each diet. In each aquarium, 12 fish with an initial mean weight of 5.23  ±  0.06  g were stocked. The fish underwent experimental feeding for 60  days, with the feed amount set at 3% of their body weight. After the experimental period, growth performance (weight gain, length gain, average daily gain, specific growth rate, thermal growth co-efficient, condition factor and survival rate), nutritional indices (feed conversion ratio, protein efficiency ratio, annual net protein utilization), proximate composition of muscle (protein, lipid, carbohydrate, ash and moisture), hematological parameters (RBC, WBC, hemoglobin, hematocrit, MCV, MCH, MCHC, total protein, albumin and globulin), serum lipid and enzymatic parameters (total cholesterol, HDL, LDL, triglycerides, ALP, AST, ALT, amylase, lipase and protease), and bioaccumulation of Zn in different organs of fish were estimated following standard methods. Growth analysis revealed that C. batrachus fed with Zn-NPs at 40  mg/kg of feed had significantly (p  <  0.05) improved growth performance (WG  =  18.87  ±  0.91  g, SGR  =  2.52  ±  0.06% g/day, TGC  =  1.09  ±  0.05 and CF  =  1.47  ±  0.12), nutritional indices (FCR  =  1.35  ±  0.06, PER  =  2.24  ±  0.10 and ANPU  =  41.46  ±  2.56%), hematological parameters, and enzymatic activity compared to control and other groups. The optimal dietary supplementation of Zn-NPs for final weight, weight gain and specific growth rate of C. batrachus was estimated to be ranged between 30.4 and 30.5  mg/kg per diet, respectively. [ABSTRACT FROM AUTHOR]

The pharmacokinetics and residue depletion of doxycycline (DOX) in striped catfish (Pagasianodon hypophthalmus) after oral dosage were investigated. The pharmacokinetic experiment was conducted in an aquarium, while the experiment of residue depletion was performed in both an aquarium and earth ponds. Medicated feed was administered orally using the gavage method at a dosage of 20 mg/kg body weight. Blood, liver, and kidney from medicated fish samples were collected. In the depletion experiments, fish were fed medicated feed for five consecutive days at a dosage of 20 mg/kg body weight, with samples collected during and after medication. The concentrations of DOX were quantified using an LC–MS/MS system. The pharmacokinetics parameters of DOX in striped catfish included the absorption rate constant (ka), absorption half‐life (T1/2abs), maximal plasma concentration (Cmax), time to maximal plasma concentration (Tmax), and area under the plasma concentration–time curve from time 0 to 96 h (AUC0–96 h) which were 0.12 h−1, 5.68 h, 1123.45 ng/mL, 8.19 h, and 25,018 ng/mL/h, respectively. Residue depletion results indicated that the withdrawal times of DOX in muscle (with skin) from fish kept in the aquarium were slightly longer than that in fish raised in earth ponds, corresponding to 194 degree‐days compared with 150 degree‐days. In conclusion, administration of DOX at the dosage of 20 mg/kg body weight can be used for treatment of bacterial infections in striped catfish, and a withdrawal time of 5 days at 29.4°C will ensure consumer food safety due to the rapid depletion of DOX from muscle and skin. [ABSTRACT FROM AUTHOR]

The study of reproductive biology is extremely crucial in fishery. Pachypterus atherinoides (Bloch, 1794) is a good food as well as an ornamental catfish in the World. The present study aims to examine the seasonal reproductive behavior of P. atherinoides regarding both its lentic and lotic ecosystems. The study was conducted over two years in selected lentic and lotic aquatic ecosystems of the Jhargram and Paschim Medinipur districts of West Bengal, India using the seasonally observed gonadosomatic index (GSI), fecundity, and gonad maturation stages for both habitats in the study area. The study reveals P. atherinoides to show single annual spawning between June-September. No significant difference was found regarding breeding period in terms of lentic and lotic aquatic ecosystems. This study can help aquaculturists regarding the culture, captive breeding, and conservation of P. atherinoides, as well as researchers regarding the biometric study of another fish. [ABSTRACT FROM AUTHOR]

Species of the catfish genus Rineloricaria are common in the Paraíba do Sul River basin, in southeastern Brazil; here we present a revision of the taxonomic diversity and geographic distribution of the species of the genus inhabiting the basin, based on novel morphologic and molecular data. Five species delimitation methods based on cytochrome C oxidase subunit 1 nucleotide sequences yielded comparable molecular operational taxonomic units. The automatic barcode gap discovery, assemble species by automatic partitioning, barcode index number, and Bayesian implementation of the Poisson tree process methods supported the recognition of five evolutionary lineages. These taxonomic units were assigned to the previously described Rineloricaria nigricauda, Rineloricaria steindachneri, Rineloricaria zawadzkii, and Rineloricaria nudipectoris, and an additional undescribed species. R. zawadzkii was further divided into two intraspecific geographically structured lineages using the generalized mixed Yule coalescent delimitation method. A maximum likelihood phylogenetic analysis revealed that the five lineages from the Paraíba do Sul have closer relationships to different species from southern and southeastern Brazil (Ribeira de Iguape, Lagoa dos Patos, Uruguay, Paraguay, and Parana river basins) than to each other. Based on the analysis of lectotypes, recently collected material, and specimens from ichthyological collections, the poorly described R. nigricauda and R. steindachneri are redescribed following current descriptive standards. The undescribed species from the middle and upper Paraíba do Sul River basin is formally described. The description of a new species, along with the description of species boundaries in R. nigricauda and R. steindachneri, contributes to the knowledge of the ichthyofauna of the Paraíba do Sul River basin and adjacent coastal drainages of southeastern Brazil. An identification key for the species of Rineloricaria occurring in the Paraíba do Sul River basin is provided. [ABSTRACT FROM AUTHOR]

In a recent study based on the generalized mixed Yule coalescent method for delimiting species, a threshold of 2% genetic distance using cytochrome c oxidase subunit I sequences was used to delimit the species of Microglanis. That action resulted in assembling several populations of Microglanis from Atlantic coastal rivers between Rio Grande do Sul and São Paulo states as a single species, Microglanis cottoides, including Microglanis cibelae as a junior synonym. We reexamined these populations and found three species diagnosed by their morphology and that constitute separate mtDNA lineages, including a new species. The synonym of M. cibelae and M. cottoides is reviewed and refuted based on morphological and molecular evidence. M. cibelae and the new species are sympatric and occasionally syntopic in the Tramandaí, Mampituba, and Araranguá river basins. The new species is distinguished from M. cibelae and M. cottoides by the anterior margin of the posttemporosupracleitrum narrow articulated with the epioccipital, the short mental and maxillary barbels, and depressed head and body. [ABSTRACT FROM AUTHOR]

Moina sp. recently has attracted the interest of hatchery operators because it is a renewable resource and has a low production cost. The effect of live and frozen forms of Moina in replacing Artemia during the larval rearing of river catfish, Pangasius nasutus, Bleeker, 1863, was investigated for 21 days. The eight-day-old posthatchling larvae were fed with live Moina (LM), frozen Moina (FM), and live Artemia (LA), of which LA served as control. The feeding trials were done in triplicate. There was no significant difference in the final mean weight and specific growth rate between all treatments. However, the larvae exhibited significantly (P <.05) higher survival when fed with LM (27.2 ± 1.1%) against LA (15.9 ± 3.9%) and FM (1.1 ± 0.7%). As a conclusion, live Moina could be used to replace Artemia in the larval rearing of P. nasutus based on comparable growth performance and improved survival. [ABSTRACT FROM AUTHOR]

Astronomical discharge of facial cosmetic products into the aquatic environments exposes aquatic organisms to these pollutants. Eight facial cosmetic products such as Milani Powder, Ponds Primer, Zikel Powder, Zaron concealer, Glam gal's foundation, Maybelline foundation, L.A Girl concealer and Milk of Magnesia were evaluated for relative acute toxicity (single and joint action) against Clarias gariepinus in static laboratory bioassays. Single action toxicity data were statistically analysed based on Probit, while the Synergistic Ratio and Concentration - Addition analysed joint action. Results of acute toxicity (single action) based on 96hrLC50 values showed that Milani Powder (184.14 mg/l) was the most toxic, followed by Ponds Primer (230.95 mg/l), Zikel powder (233.58 mg/l), Aaron concealer (384.47 mg/l), Glam Gals' foundation (421.83 mg/l), Maybelline foundation (565.32 mg/l), L, A Girl concealer (587.75 mg/l) and Milk of Magnesia (2218 mg/l) in descending order of toxicity. Joint action toxicity evaluation of the binary, trinary and quaternary mixtures subjected to the Synergistic Ratio and Concentration showed that binary mixtures tended towards synergism and antagonism in varied ratios and combinations. The ratio of toxicity units for all mixtures interaction tended to synergism and could be dangerous to the biota. Therefore, strict regulation standards should be enforced to protect the environment and make eco-friendly alternative ingredients that can be incorporated into these products. [ABSTRACT FROM AUTHOR]

Calcium is the mineral most needed by the body. One of the diseases caused by calcium deficiency is osteoporosis, which is a degenerative condition caused by a diet low in minerals such as calcium and phosphorus. The sailfin catfish (Pterygoplichthys pardalis) bones has been proved to contain a lot of minerals and phosphorus. The population of the sailfin catfish in Tempe Lake, Wajo Regency, has increased rapidly in recent years. The sailfin catfish bones can be processed into crackers. The purpose of this study was to analyze the quality characteristics of crackers fortified with the sailfin catfish bone meal (Pterygoplichthys pardalis). The acceptability of crackers was tested hedonically by 100 panelists to determine the best variation in the addition of the sailfin catfish bone meal. The chemical analysis included the moisture, ash, fat, protein, carbohydrate, calcium, and phosphorus content of crackers from the best treatment. Hedonic test results showed that the addition of 20% of the sailfin catfish bone meal produced the best crackers. Chemical analysis showed a significant increase in ash content to 11.65% compared to the control of 3.25%. Protein and fat levels also increased to 11.44 and 15.63%, respectively, from the control of 11.21 and 13.55%. Calcium and phosphorus levels also increased significantly in the best crackers, to 4.37 and 2.64% compared to the control of 0.10 and 0.70%, respectively. These findings indicate that the crackers have the potential to be used as a food additive to address calcium and phosphorus deficiencies in growing children and the elderly. [ABSTRACT FROM AUTHOR]

The Mekong giant catfish Pangasianodon gigas is endemic to the Mekong River and is one of the largest freshwater fish. This critically endangered species is a popular food for local people and a commercially essential fishery resource. Ecological knowledge of this catfish is required to conserve it. However, its ecology has not yet been well studied. We monitored the food intake of the Mekong giant catfish in a stable aquarium for over 13 years. We analyzed their feeding rhythms and fasting periods. The feeding rhythm (circannual rhythm) of the Mekong giant catfish over 13 years and its temporal variations were revealed. Four of the six catfish showed feeding cycles that extended more than one year (395.7 days). Five of the six catfish showed prolonged fasting periods over 30 consecutive days. These patterns coincide with the wet/dry seasons in Thailand, corresponding to the abundance of catfish food resources (Cladophora spp.). Furthermore, it is suggested that the Mekong catfish has acquired the physiological ability to tolerate a fasting state for about 1 year, possibly because this species may have survived many critical situations in the Mekong River in the past, such as food insufficiency. At the same time, however, this also indicates that the fish is highly dependent on Cladophora spp. as a food item and may not be able to substitute other food items. From these, reductions in food items or feeding habitats for catfish after damming in many places of the Mekong River basin may decrease the population size of this species. [ABSTRACT FROM AUTHOR]

Importance: Over the past decade, catfish farming has increased in Southeast Asia. However, there has been no existing for pharmacokinetic data in the hybrid catfish ( Clarias macrocephalus x C. gariepinus). Objective: This study was designed to evaluate the pharmacokinetic characteristics of oxytetracycline (OTC) in the hybrid catfish, following single intravascular (IV) or oral (PO) administration at a single dosage of 50 mg/kg body weight (BW). Methods: In total, 140 catfish (each about 100-120 g BW) were divided into two groups (n = 70). Blood samples (0.6-0.8 mL) were collected from ventral caudal vein at pre-assigned times up to 144 h (sparse samples design). OTC plasma concentrations were analyzed using high-performance liquid chromatography-photodiode array detector. Results: The pharmacokinetic parameter of OTC was evaluated using a non-compartment model. OTC plasma concentrations were detectable for up to 144 and 120 h after IV and PO, respectively. The elimination half-life value of OTC was long with slow clearance after IV administration in hybrid catfish. The average maximum concentration value of OTC was 2.72 µg/mL with a time at the maximum concentration of 8 h. The absolute PO bioavailability was low (2.47%). Conclusions and Relevance: These results showed that PO administration of OTC at a dosage of 50 mg/kg BW was unlikely to be effective for clinical use in catfish. The pharmacodynamic properties and clinical efficacy of OTC after multiple medicated feed are warranted. [ABSTRACT FROM AUTHOR]

The study of length-weight relationship and condition factor was carried out on of freshwater catfish, Clupisoma garua. Altogether 280 samples were collected from three different rivers of North India (Gomti, Ganga and Rapti). The value of b ranges from 2.571-2.720 for the length-weight relationship in the current study. The growth pattern showed significant deviation from isometric value (b=3), therefore all the three populations are supposed to follow negative allometric growth pattern. The coefficient of determination (r2) was found to be in the range of 0.8059-0.8587. The value of condition factor in the present study was found to be more than '1' in all the three populations of the fish which indicated the good health conditions. The present study is considered to be important for assessment of the biology of the fish that could help in conservation and management of C. garua in the North Indian Rivers. [ABSTRACT FROM AUTHOR]

A potamodromous species found in both fresh and brackish water, Clupisoma garua (Hamilton, 1822) is also known as "garuabachcha". It belongs to the order Siluriformes and the family Schilbeidae. The species mostly inhabits Asian countries such as Bangladesh, India, Pakistan and Nepal and is predominantly found in expansive freshwater reservoirs. The species are classified as Least Concern (LC) by the IUCN, although they are classified as Vulnerable (Vu) according to the CAMP and CAFF studies. The species is an omnivorous carnivore that consumes insects, molluscs, crustaceans and small fish in its natural habitat. This species possesses both utilitarian and aesthetic qualities and individuals of moderate size are also regarded as sport fish in India. The species is reported to have a broad distribution; however, it is at risk in certain areas, such as southern West Bengal, due to excessive fishing and human activity. This review aims to provide comprehensive information on the species 'garuabachcha', including its characteristics, significance and recommended conservation strategies. [ABSTRACT FROM AUTHOR]

Over the course of an approximately 11-month period, an outdoor, freshwater, mixed species, recirculating, display system at a public aquarium experienced intermittent mortalities of channel catfish (Ictalurus punctatus) and blue catfish (I. furcatus). Catfish acutely presented for abnormal buoyancy, coelomic distention, and protein-rich coelomic effusion. Gross lesions typically involved massive coelomic distension with protein-rich effusion, generalized edema, and gastric hemorrhage and edema. Microscopically, primary lesions included renal tubular necrosis, gastric edema with mucosal hemorrhages, and generalized edema. Aerobic culture and virus isolation could not recover a consistent infectious agent. Intracoelomic injection of coelomic effusion and aspirated retrobulbar fluid from a catfish into naïve zebrafish (bioassay) produced peracute mortality in 3 of 4 fish and nervous signs in the fourth compared with 2 saline-injected control zebrafish that had - no mortality or clinical signs. Kidney tissue and coelomic effusion were submitted for gas chromatography tandem mass spectrometry by multiple reaction monitoring against laboratory standards, which detected the presence of multiple pyrethroid toxins, including bioallethrin, bifenthrin, trans-permethrin, phenothrin, and deltamethrin. Detection of multiple pyrethroids presumably reflects multiple exposures with several products. As such, the contributions of each pyrethroid toward clinical presentation, lesion development, and disease pathogenesis cannot be determined, but they are suspected to have collectively resulted in disrupted osmoregulation and fluid overload due to renal injury. Pesticide-induced toxicoses involving aquarium fish are rarely reported with this being the first description of pyrethroid-induced lesions and mortality in public aquarium-held fish. [ABSTRACT FROM AUTHOR]

This research aims to determine the optimal dose of boiled mackerel tuna mixture on HI-PRO VITE 781 feed on gonadal maturity index and feed conversion ratio of transgenic mutiara catfish G4 in indoor hatchery maintenance at optimal temperature. This research was conducted at the Hatchery of the Faculty of Fisheries and Marine Sciences, Universitas Padjadjaran. The method used was an experimental method with a completely randomized design (CRD) method with four treatments, namely the difference in the dose of boiled mackerel tuna administration in comercial feed and three replications. The treatment in this study was the administration of boiled mackerel tuna doses of 3.5%, 2.5%, 1.5% in mixed feeds to G4 transgenic mutiara catfish and tested on non-transgenic mutiara catfish with a percentage of 3.5% female weight biomass and then added an 30 g HI-PRO-VITE 781 with two times feeding frequency. The research parameters included gonad maturity index and feed conversion ratio. The results showed that feeding a mixture of boiled mackerel tuna and HI-PRO-VITE 781 had a significant effect on the gonadal maturity index and feed conversion ratio. Feeding boiled mackerel tuna at 1.5% was the best treatment with a gonadal maturity index of 47.16% for females and 4.98% for males and a feed conversion value of 1.19 for 56 days of rearing. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to quantify the economic costs and impacts of off‐flavor on U.S. catfish farms. Methods: A survey was conducted to quantify the costs and economic methods using enterprise budget techniques to enumerate the costs of off‐flavor on catfish farms. Result: Diuron was the most popular‐choice algicide for off‐flavor management. Direct annual costs associated with off‐flavor management on catfish farms amounted to US$40 million/year. Total industry economic losses due to off‐flavor was estimated at $73.9 million in 2022. Conclusion: The study confirms the continued significance of off‐flavor in U.S. catfish farming and quantifies the associated economic effects. Impact statementEvaluating the economic cost associated with off‐flavor management practices provides insights into the economic significance of this persistent problem on U.S. catfish farms. This study found that the annual cost of off‐flavor amounts to $2325/ha and $0.272/kg, accounting for 10% of the total cost of production. The direct economic loss to the industry amounted to $40 million annually, with a total negative economic impact of $74 million in 2022. [ABSTRACT FROM AUTHOR]

African catfish is a popular freshwater aquaculture species as it can be farmed at high stocking density. However, high stocking density caused growth and health impairment. Hence, nutritional approach such as feed additive can be applied in fish farming to overcome this issue. This study evaluated the impacts of ginger (Zingiber officinale) leaf powder (GLP) on growth performance, digestive enzymes activities, antioxidative response, and disease resistance towards Edwardsiella tarda infection in African catfish. A feeding trial was performed using a control diet and four formulated diets with GLP at 1, 2, 3, and 4%. Ginger is an herb used in cuisine and traditional medicine. It was reported possesses medicinal values such as antimicrobial, anti-oxidant, and immune system modulator. After eight weeks, the growth performance of GLP-treated African catfish was significantly improved than control, and the best results were observed in the 2 and 3% groups (p<0.05). Meanwhile, fish supplemented with 1 and 4% GLP demonstrated comparable growth performance. There was a significant decreasing trend in FCR, HSI, and VI, where the lowest values were recorded by the 2 and 3% GLP diet groups, followed by 1% GLP, 4% GLP, and control groups (p<0.05). The digestive enzymes activity, including amylase, lipase, and protease, was significantly higher in dietary GLP groups than in control, where the highest activity was exhibited by groups 2 and 3% GLP (p<0.05), followed by 1% and 4% GLP groups. There was an increasing trend in the antioxidative response, where the GLP-treated groups had significantly higher catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) activities than the control, and the highest was observed in fish fed with 2 and 3% GLP (p<0.05). Furthermore, the GLP-treated groups had a significantly higher cumulative survival rate than the control, where 2 and 3% GLP groups demonstrated the highest survival (p<0.05), followed by 1 and 4% GLP groups. In summary, this study revealed that dietary GLP potentially enhanced African catfish production at recommended doses of 2 and 3%. [ABSTRACT FROM AUTHOR]

The genus Silurus, an important group of catfish, exhibits heterogeneous distribution in Eurasian freshwater systems. This group includes economically important and endangered species, thereby attracting considerable scientific interest. Despite this interest, the lack of a comprehensive phylogenetic framework impedes our understanding of the mechanisms underlying the extensive diversity found within this genus. Herein, we analyzed 89 newly sequenced and 20 previously published mitochondrial genomes (mitogenomes) from 13 morphological species to reconstruct the phylogenetic relationships, biogeographic history, and species diversity of Silurus. Our phylogenetic reconstructions identified eight clades, supported by both maximum-likelihood and Bayesian inference. Sequence-based species delimitation analyses yielded multiple molecular operational taxonomic units (MOTUs) in several taxa, including the Silurus asotus complex (four MOTUs) and Silurus microdorsalis (two MOTUs), suggesting that species diversity is underestimated in the genus. A reconstructed time-calibrated tree of Silurus species provided an age estimate of the most recent common ancestor of approximately 37.61 million years ago (Ma), with divergences among clades within the genus occurring between 11.56 Ma and 29.44 Ma, and divergences among MOTUs within species occurring between 3.71 Ma and 11.56 Ma. Biogeographic reconstructions suggested that the ancestral area for the genus likely encompassed China and the Korean Peninsula, with multiple inferred dispersal events to Europe and Central and Western Asia between 21.78 Ma and 26.67 Ma and to Japan between 2.51 Ma and 18.42 Ma. Key factors such as the Eocene-Oligocene extinction event, onset and intensification of the monsoon system, and glacial cycles associated with sea-level fluctuations have likely played significant roles in shaping the evolutionary history of the genus Silurus. [ABSTRACT FROM AUTHOR]

Copyright of Indonesian Fisheries Processing Journal / Jurnal Pengolahan Hasil Perikanan Indonesia is the property of IPB University 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.)

Edwardsiellosis of catfish caused by Edwardsiella ictaluri and Edwardsiella piscicida remains one of the most significant diseases in U.S. catfish aquaculture. Economic losses related to this disease are currently unknown. This work sheds light on the losses associated with E. ictaluri and E. piscicida in catfish aquaculture. The robust economic approach employed is grounded in farm-level production data and long-term disease trends in the industry. Direct farm-level economic losses from Edwardsiellosis ranged from −$3,485 to −$13,320/ha causing industrywide economic losses of −$5.2 to −$17.6 million/year. The lost revenue due to Edwardsiellosis ranged from −$8.4 to −$24.8 million/year causing a negative economic impact of −$15.5 to −$45.9 million/year. The economic losses and negative impacts of Edwardsiellosis are relatively greater on the foodfish sector compared to the fingerling sector. This work provides a platform for a more accurate estimation of the true economic impacts of diseases for aquaculture sectors for which commercial farm data is available. [ABSTRACT FROM AUTHOR]

The taxonomy of the blood-feeding candiru catfish genus Paravandellia is poorly resolved, incomplete, and hindered by a complex nomenclatural history, with many species being arbitrarily synonymized, considerable morphological and geographic variation being unevaluated, and morphological boundaries between the genus and its sister, Paracanthopoma, differing among authors. Herein, we describe three new species of Paravandellia based on photomicroscopy, cleared and stained specimens, and µCT imagery. We also reevaluate diagnostic character states for Paravandellia and Paracanthopoma, propose a new character to diagnose Paravandellia, and present our discovery of a possible type specimen of Parabranchioica teaguei and additional non-type specimens of Branchioica bertoni, junior synonyms of Parav. oxyptera. Based on these observations, we confirm Parav. alleynei and a recent newly described species of Paracanthopoma as members of a rediagnosed, putatively monophyletic Paravandellia, increasing its richness from two to seven species. We also discuss interrelationships of Paravandellia species based on the characters described. [ABSTRACT FROM AUTHOR]

Patterns of genetic variation reflect interactions among microevolutionary forces that vary in strength with changing demography. Here, patterns of variation within and among samples of the mouthbrooding gafftopsail catfish (Bagre marinus, Family Ariidae) captured in the U.S. Atlantic and throughout the Gulf of Mexico were analyzed using genomics to generate neutral and non‐neutral SNP data sets. Because genomic resources are lacking for ariids, linkage disequilibrium network analysis was used to examine patterns of putatively adaptive variation. Finally, historical demographic parameters were estimated from site frequency spectra. The results show four differentiated groups, corresponding to the (1) U.S. Atlantic, and the (2) northeastern, (3) northwestern, and (4) southern Gulf of Mexico. The non‐neutral data presented two contrasting signals of structure, one due to increases in diversity moving west to east and north to south, and another to increased heterozygosity in the Atlantic. Demographic analysis suggested that recently reduced long‐term effective population size in the Atlantic is likely an important driver of patterns of genetic variation and is consistent with a known reduction in population size potentially due to an epizootic. Overall, patterns of genetic variation resemble that of other fishes that use the same estuarine habitats as nurseries, regardless of the presence/absence of a larval phase, supporting the idea that adult/juvenile behavior and habitat are important predictors of contemporary patterns of genetic structure. Gafftopsail catfish show high levels of genetic structuring across their distribution in the U.S., Atlantic and Gulf of Mexico. Non‐neutral data present two contrasting signals of structure and historical demography is likely an important driver of patterns of neutral and non‐neutral genetic variation. Results of this study are similar to what is seen in other fishes that use the same estuarine habitats as nurseries, but gafftopsail catfish lack a larval phase, supporting the idea that adult/juvenile behavior and habitat use are important predictors of contemporary patterns of genetic structure. [ABSTRACT FROM AUTHOR]

Xenogenesis has been recognized as a prospective method for producing channel catfish, Ictalurus punctatus ♀ × blue catfish, I. furcatus ♂ hybrids. The xenogenesis procedure can be achieved by transplanting undifferentiated stem cells derived from a donor fish into a sterile recipient. Xenogenesis for hybrid catfish embryo production has been accomplished using triploid channel catfish as a surrogate. However, having a surrogate species with a shorter maturation period, like white catfish (Ameiurus catus), would result in reduced feed costs, labor costs, and smaller body size requirements, making it a more suitable species for commercial applications where space is limited, and as a model species. Hence, the present study was conducted to assess the effectiveness of triploid white catfish as a surrogate species to transplant blue catfish stem cells (BSCs) and channel catfish stem cells (CSCs). Triploid white catfish fry were injected with either BSCs or CSCs labeled with PKH 26 fluorescence dye from 0 to 12 days post hatch (DPH). No significant differences in weight and length of fry were detected among BSCs and CSCs injection times (0 to 12 DPH) when fry were sampled at 45 and 90 DPH (P > 0.05). The highest survival was reported when fry were injected between 4.0 to 5.5 DPH (≥ 81.2%). At 45 and 90 DPH, cell and cluster area increased for recipients injected from 0 to 5.2 DPH, and the highest cluster area values were reported between 4.0 to 5.2 DPH. Thereafter, fluorescent cell and cluster area in the host declined with no further decrease after 10 DPH. At 45 DPH, the highest percentage of xenogens were detected when fry were injected with BSCs between 4.0 to 5.0 and CSCs between 3.0 to 5.0 DPH. At 90 DPH, the highest number of xenogens were detected from 4.0 to 6.0 DPH when injected with either BSCs or CSCs. The current study demonstrated the suitability of white catfish as a surrogate species when BSCs and CSCs were transplanted into triploid white catfish between 4.0 to 6.0 DPH (27.4 ± 0.4°C). Overall, these findings allow enhanced efficiency of commercializing xenogenic catfish carrying gametes of either blue catfish or channel catfish. [ABSTRACT FROM AUTHOR]

In this study, effect of different stocking densities on growth, oxidative stress, antioxidant enzymes, and hematological and immunological values in European catfish (Silurus glanis) was examined. The control (0.06 kg fish/L) and trial (T) 1 (0.08 kg fish/L), T2 (0.10 kg fish/L), and T3 (0.12 kg fish/L) stocking groups were used. Each stocking group with three replicates was carried out in a tank at 22 ± 2 °C water temperature. The fish were fed three times daily for 60 days. The highest final weight (123.3–171.6 g), weight gain (84.13–159.6%), specific growth rate (1.40–2.66%), feed intake (138.5–178.2 g/fish), and feed conversion rate (1.12–1.65%) were provided from the control and T1 stockfish (p > 0.05), followed by the T2 and T3 stockfish (p < 0.05), respectively. The lowest oxidant level and the highest reduced glutathione level and superoxide dismutase, catalase, and glutathione peroxidase activities were obtained from the control fish, followed by the T1, T2, and T3 stockfish, respectively (p < 0.05). In addition, parallel to the increase in stocking density, the erythrocyte count, hematocrit, hemoglobin, erythrocyte volume, corpuscular hemoglobin, and corpuscular hemoglobin concentration values of fish increased (p < 0.05), but the leukocyte count, nitroblue tetrazolium activity, total protein, and immunoglobulin-M values decreased (p < 0.05). The high stocking densities caused oxidative stress in fish, negatively affecting their health and growth and feed evaluation values. However, the stocking density could increase to 0.08 kg/L from 0.06 kg/L in the European catfish fingerling reared in the recirculating aquaculture system by maintaining the water quality and applying good care and feeding. [ABSTRACT FROM AUTHOR]

The Brazilian Atlantic Forest, one the five main biodiversity hotspots in the world, still houses many organisms that are rare and unknown to science, mostly concentrated in mountain ranges. Herein, we describe a rare new species of Cambeva from the Rio Tietê drainage at the Serra da Mantiqueira, exhibiting a caudal fin color pattern comprising a light-yellowish–white bar posteriorly edged by a black pigmented area. A similar color pattern was described for C. castroi, C. diabola, and C. melanoptera, also endemic to the Rio Paraná basin, and considered evidence of close relationships among these three species. However, other morphological characteristics highly suggest that the new species is not closely related to C. castroi, C. diabola, and C. melanoptera). Herein, we perform a molecular phylogenetic analysis using two mitochondrial genes and one nuclear gene, including all species with that bicolored caudal pattern. The analysis strongly supports the new species as a member of the alpha-clade, and therefore as distantly related to those three species belonging to the beta-clade, indicating that this color pattern has homoplastically arisen in Cambeva. The data reported here reinforce the urgent need for field studies to better understand the different evolutionary patterns found in the genus, since an intense process of environmental degradation is in course. [ABSTRACT FROM AUTHOR]

This study summarizes new data on induced spawning of Steindachneridion parahybae, focusing on the aggressive behavior of females. This study characterizes the vasotocinergic system using immunohistochemistry, highlighting the potential influence of arginine-vasotocin (AVT) on reproductive physiology. Two experimental groups were proposed: (A) control, with one female in the aquarium, and (B) experimental, with two females in the same aquarium. Dominant (D) females presented a more aggressive behavior and did not show any injury. They apparently had a length and body mass higher than injured nondominant (ND) females. The analysis identified positive AVT immunoreactive (ir) neurons exclusively within the preoptic area, including parvocellular, magnocellular, and gigantocellular subpopulations, containing fibers-ir extending into the pituitary gland. Cellular and nuclear areas were greater in D compared to ND in the magnocellular subpopulation. There were no differences between parvocellular and gigantocellular subpopulations. There was a difference on the steroid plasma profile of cortisol (more in ND than in D) and 17α,20β-dihydroxy-4-pregnen-3-one (more in D than in ND). Furthermore, control and D females presented higher optical densities for AVT-ir, gonadotropin-releasing hormone-ir, and luteinizing hormone-ir than ND. In general, there were no differences in the results of female (control group) with D females. The AVT system is highly complex, possibly counting multiple sites of action during artificial reproduction and acting directly and/or indirectly associated with behavioral and physiological changes in S. parahybae females when induced to spawning. [ABSTRACT FROM AUTHOR]

Fish is an important source of food and income for a significant portion of the Amazonian population, especially those who live along the rivers and lakes in the region. Pseudoplatystoma punctifer (Castelnau, 1855), known as surubim, is a species of Neotropical catfish widely exploited by fisheries and commercially valuable in the Guaporé River basin, Brazil. However, population dynamics are poorly known in the region. To understand the population structure and reproductive biology aspects of the surubim, monthly experimental fisheries were carried out in the São Miguel River, state of Rondônia, Brazil, between August 2020 and July 2021. The captured fish were weighed, and its gonads were removed and weighed for histological analyses (microscopic description) and classification of the maturation stages (macroscopic description). The collected gonads were fixed in 10% buffered formalin, dehydrated, cut into 4‐μm‐thick sections, and stained with hematoxylin and eosin. A total of 34 individuals were collected (20 females and 14 males), showing positive allometric growth and condition factor from 0.81 to 1.79 for females and males, respectively. Females were larger in size and weight than males. P. punctifer reaches its first maturation at an average length of 68.30 cm, indicating the importance of respecting the minimum capture size as an alternative to ensure the natural stocks of this fishery resource in the region. The results provide support for the establishment of public policies and actions for conservation, management, and regulation of fishing. [ABSTRACT FROM AUTHOR]

The spawning of striped catfish which is very dependent on the season and environmental conditions results in the unavailability of mature gonad broodstock during the dry season. The alternative that is often done is by biological stimulation using the ovaprim hormone and laserpuncture technology. The purpose of this study was to determine the effect of giving the ovaprim hormone, laserpuncture induction and a combination of the two on the speed of spawning time and the fecundity value of Striped catfish. This study used an experimental method with a completely randomized design with 3 treatments and 6 replications. The results of this study were the average spawning time for broodstock treated with laserpuncture and ovaprim hormone and the fecundity value was significantly different from the other treatments (p<0.05). Based on the results of the study, it can be concluded that the combination of 0.5 ml/kg of ovaprim hormone and laser puncture at a dose of 0.5 J/cm² for 32.66 seconds can speed up the spawning time and fecundity of striped catfish. [ABSTRACT FROM AUTHOR]

Simple Summary: Personality and light are crucial to ensure the welfare of aquatic animals. To understand how personality affects the light color selection of fish, we tested the behaviors with different personalities under six colors of light: violet (410–420 nm), yellow (580–590 nm), green (550–560 nm), red (620–630 nm), blue (470–480 nm), and white. In this study, the yellow catfish Pelteobagrus fulvidraco preferred the yellow and green light over the other light colors. After identifying their preferred light colors, bold individuals reduced their frequency of exploration. The results showed that bold individuals could make a quick decision for light color selection. This study provides a reference for the welfare of juvenile yellow catfish in aquaculture. Personality, which matters for animal welfare, demonstrates behavioral differences. Light is one of the most important factors in aquaculture. However, how fish personality affects light color selection is unclear. In this study, we tested the personality of yellow catfish Pelteobagrus fulvidraco juveniles and then quantified the selective behaviors of different personalities under six light colors: violet (410–420 nm), yellow (580–590 nm), green (550–560 nm), red (620–630 nm), blue (470–480 nm), and white. The results showed that juveniles preferred the yellow and green light over the other colors of light, probably due to different reasons. The average cumulative dwell time in yellow (32.81 ± 5.22%), green (21.81 ± 3.58%), and red (26.36 ± 4.89%) lights was significantly longer than the other light colors, and the average visit frequency in green light (32.00 ± 4.93%) was the most. Juveniles had the longest total moved distance in green light. Moreover, the results demonstrated that shy and bold individuals had the same preference for the green light. Bold individuals could find the preferred light colors rapidly and make quick decisions for light color selection. After identifying the preferred light colors, bold individuals reduced the frequency of exploration. This study provides a theoretical basis for the welfare of juvenile yellow catfish in aquaculture. [ABSTRACT FROM AUTHOR]

The Bagrid catfish, Bagrus orientalis, historically sustained communities in the Rufiji River basin (RRB), Tanzania, but has rapidly declined due to high consumer demand and unsustainable fishing. Consequently, a Ramsar site was designated within the RRB, although its potential to revitalize overexploited populations beyond its boundaries is uncertain because of limited information on genetic connectivity. To address this uncertainty, 158 partial cytochrome oxidase subunit I sequences of B. orientalis were analyzed to quantify genetic connectivity in the RRB. We observed significant genetic differentiation, indicating limited connectivity among populations. Populations in the Ramsar site were genetically connected to those in the Kilombero Valley Floodplain (KVFP), but were distinct from those in Ruaha and Rufiji, which clustered separately. Our findings suggested the Ramsar site could revitalize overexploited KVFP populations, and emphasized the need for sustained efforts against its encroachment. However, limited genetic connectivity with Ruaha and Rufiji implied that conservation measures in the site might have restricted effect in these areas. Conservation efforts should extend beyond the Ramsar site, by promoting sustainable fishing and enhancing habitat connectivity in Ruaha and Rufiji. [ABSTRACT FROM AUTHOR]