Pterophyllum Research Articles

Migration of primordial germ cells and their relationship of PGCs with sex development in transgenic germline-specific fluorescent freshwater angelfish (Pterophyllum scalare)

Primordial germ cells (PGCs), the progenitors of gametes, are essential for teleost reproduction. While their formation is conserved across teleosts, the activation, migration routes, and localization periods vary among species. In this study, we developed a novel transgenic line, Tg(ddx4:TcCFP13-nanos3), based on the Nile tilapia genome, to label PGCs with clear fluorescent signals in the freshwater angelfish (Pterophyllum scalare). Our findings reveal a complex, multistage PGCs migration process in angelfish, with a significantly extended localization period (168 hpf) compared to zebrafish (24 hpf). Notably, individual differences in PGCs abundance were observed during early somite development. Analysis of PGCs counts and subsequent sexual maturation demonstrate a potential correlation between PGCs abundance and sex determination: 90% of PGCs-reduced individuals developed as males, while 83% of PGCs-rich individuals developed as females. This study provides a foundation for understanding PGCs migration and sex development in freshwater angelfish, offering valuable insights into reproductive biology and ornamental fish species. Furthermore, this in vivo PGCs tracking system for Cichlids provides a versatile tool for advancing research and applications in germ cell biology.

Knockout of dead end 1 by CRISPR/Cas9 leads to loss of germ cells and male-biased sex development in freshwater angelfish (Pterophyllum scalare)

Knockout of dead end 1 by CRISPR/Cas9 leads to loss of germ cells and male-biased sex development in freshwater angelfish (Pterophyllum scalare)

Isolation of potential zoonotic Mycobacterium spp. from diseased freshwater angelfish (Pterophyllum scalare) from an aquarium.

Nontuberculous mycobacteria infection is one of the most common chronic bacterial diseases in ornamental aquarium fish and appears to be directly related to stressful husbandry practices. Furthermore, it also represents zoonotic potential. Here we present the isolation and characterization of non-tuberculous mycobacteria from diseased freshwater angelfish (Pterophyllum scalare) in São Paulo, Brazil. Nine discarded breeding females with signs of disease were evaluated. The fish exhibited lethargy, loss of appetite, cachexia, skin ulcers, and exophthalmia. At necropsy, four fishes presented macroscopic granulomas in the spleen. Mycobacterium chelonae, M. fortuitum, M. gordonae, M. intracellulare and M. peregrinum were isolated and identified by hsp65 PCR restriction analysis. Histopathological analysis revealed microscopic lesions compatible with mycobacteriosis, and Mycobacterium bacillus were observed by Ziehl-Neelsen stain. Notably, all Mycobacterium species identified in this study have already been reported in human patients; therefore, diseased animals may be a source of infection for people who handle fish and aquariums.

The growth performance and parasite load of angelfish juveniles Pterophyllum scalare kept at different stocking densities in two rearing systems.

This study evaluated the growth performance and parasite load of angelfish juveniles Pterophyllum scalare kept at different stocking densities using two rearing systems. The experiment was conducted in a factorial design (4x2) with four stocking densities (0.1, 0.4, 0.7, and 1.0 g/L), two type of aquarium tanks (glass and ceramic aquariums), and four replicates. The experiment lasted 60 days using 148 juvenile fish (3.05 ± 0.09 g) randomly placed in 32 aquariums (50 L) equipped with filters and aeration. All fish received two meals a day ad libitum (8:00 and 16:00). Water quality parameters such as temperature, dissolved oxygen, pH, and total ammonia were measured. At the end of the experiment, all fish were measured and weighed to determine growth performance and then subjected to parasitological analysis. The data were analyzed with a two-way ANOVA with post-hoc Tukey test (p<0.05). No effects on growth performance at different stocking densities were observed. However, there was an increase in Capillaria pterophylli infestation in the high stocking density within ceramic aquariums. Thus, this study recommends the use of 1.0 g/L for the intensive aquaculture system of freshwater angelfish, and applying cleaning management to avoid parasite infestation, particularly in ceramic aquariums.

Enrichment of Daphnia magna (Straus, 1820) with Viterna and Its Effects on the Growth and Survival Performance of the Freshwater Angelfish Pterophyllum scalare (Schultze, 1823) Larvae

Enrichment of Daphnia magna (Straus, 1820) with Viterna and Its Effects on the Growth and Survival Performance of the Freshwater Angelfish Pterophyllum scalare (Schultze, 1823) Larvae

First case of chronic systemic spironucleosis in Freshwater Angelfish (Pterophyllum scalare Schultze, 1823) in Türkiye

This study aimed to identify the cause of sustained mortality in freshwater angelfish (Pterophyllum scalare Schultze, 1823) kept at an ornamental fish production facility in Türkiye. Parasitological, bacteriological and histopathological examination were performed on moribund hybrid angelfish individuals. The moribund fish had haemorrhaged eyes, darkened skin, scale loss, ascites and false faeces. A pale liver, splenomegaly and a thinning of the intestinal wall were observed internally. The parasitological examination revealed flagellated protozoan endoparasite Spironucleus sp. in the intestine. A number of histopathological changes were observed including lipid degeneration in the liver, hemosiderin deposits as well as granulomas in the spleen, a large number of mast cells in the lamina propria of the intestine and enteritis. Numerous Spironucleus parasites were seen in the intestinal wall. According to physiological and biochemical tests, the bacterial isolates obtained from the visceral organs of some fish were identified as Citrobacter freundii. After oral metronidazole treatment, with a dose of 50 mg/kg fish daily for 5 days, a decrease in fish mortality and resumed feeding were noted. A chronic spironucleosis, which systemically affects fish by penetrating the intestinal mucosa, was identified as the cause of this sustained mortality in freshwater angelfish.

Effects of Protein Concentration in Fish Feed on Physical and Chemical Water Pollution

Nitrates are linked to higher rates of fish mortality. Fish feces discolors water, reducing clarity and affecting the metabolism of organisms. Food eaten by fish is the main source of nitrates and feces. This work studies how protein concentration in fish feed affects the production of wastes that pollute water. It is hypothesized that high protein fish foods lead to more nitrates, less clear water in addition to an increased amounts of trace amino acids entering the water column. Three experiments were performed to determine which food at a 28%, 36%, or 42% protein concentration contributed most to poor water quality. These tests were performed on feces collected from three species of fish, the freshwater angelfish, koi and the tamasaba goldfish. The tests determined that increasing the protein concentration in fish food did in fact increase nitrate levels in aquariums while water clarity and residual amino acid concentration did not necessarily increase. This is significant because it allows for greater insights into fish feeding which are important for the traditional aquarium hobby and aquaculture farms.

The effect of Artemia nauplii (Artemia franciscana) enriched with different commercial products on the growth performance of the larvae of freshwater angelfish, Pterophyllum scalare (Lichtenstein, 1823)

The present study was planned to determine an optimum live-feeding protocol for angelfish larvae (Pterophyllum scalare). Larvae with an initial weight of 0.10 mg, a length of 4.5 mm, and a depth of 1 mm were reared on three different feeding regimens for 30 days. All experimental larval groups were fed Artemia nauplii from the end of the yolk-sac resorption. The control treatment (Group I) was maintained on Artemia nauplii on days 14-28, and on Artemia nauplii + dry feed on days 29 and 30. Group II was reared with Artemia nauplii enriched with Algamac 3050 on days 14-28 and with dry feed + Artemia nauplii enriched with Algamac 3050 on days 29 and 30, whereas Group III was fed with Artemia nauplii enriched with Red Pepper on days 14-28, and with dry food + Artemia nauplii enriched with Red Pepper on days 29 and 30. The highest weight (37.8±0.51 mg) and length (15.8±0.35 mm) were determined in Group II with significant differences from the control group (p&lt;0.05). However, enrichment treatments were comparable in terms of growth performance (p&gt;0.05). The survival rate of the larvae in the treatments varied between 70-75% without significant differences (p&gt;0.05). Overall, the study results suggest that a feeding protocol for angelfish larvae with the administration of Artemia nauplii during the first two weeks after hatching and then enriched Artemia with Algamac 3050 over the following 14-28 days followed by a gradual weaning onto dry feed.

Essential oils from Cymbopogon citratus and Lippia sidoides in the anesthetic induction and transport of ornamental fish Pterophyllum scalare.

This study verified the effects of essential oils from Lippia sidoides (EOLS) and Cymbopogon citratus (EOCC) on the anesthesia of freshwater angelfish (Pterophyllum scalare) of two different sizes (juveniles I (0.82g) and II (2.40g)) and the transport (8h) of juveniles II. Fish were exposed to different concentrations of EOLS and EOCC: 0, 10, 25, 50, 75, 100, 150, 200, and 250mgL-1. Ventilatory rate (VR) and transport for 8h with 0, 10, and 15mgL-1 of each essential oil were evaluated in juveniles II. The major components found in EOLS and EOCC were carvacrol (44.50%) and α-citral (73.56%), respectively. The best sedation and anesthesia times for both essential oils were obtained with 10 and 25mgL-1 and 200 and 250mgL-1 for juveniles I and II, respectively. Fish sedated with EOLS had lower VR values than the other treatments. Blood glucose levels were higher in ornamental fish transported with 10 and 15mg EOLS L-1 and 15mg EOCC L-1. Hepatic glycogen values were higher in the control group. In general, fish transported with 10mg EOLS L-1 showed fewer gill histological alterations than other transported fish. When the type of lesion was evaluated, the highest gill alterations occurred in fish transported with EOCC. In conclusion, 10mg EOLS L-1 could be used to transport of juveniles II because although this concentration increased blood glucose levels, it decreased the VR and muscle glycogen levels and caused only mild alterations to the gills.

First Ever Whole Genome Sequencing and De Novo Assembly of the Freshwater Angelfish, Pterophyllum scalare.

This research work is the first to ever sequence and perform a de novo assembly of the genome of the freshwater angelfish, Pterophyllum scalare . The final genome assembly consisted of 15,486 contigs and was 734.79 Mb in size with an 86.5% BUSCO score. Functional annotation of the genome revealed 24,247 protein-coding sequences related to other fish species. 14,329 (59%) of the identified genes were orthologous to Archocentrus centrarchus , a closely related South American cichlid.

Water temperature modulates social behavior of ornamental cichlid (Pterophyllum scalare) in an artificial system

ABSTRACT Environmental changes can cause physiological alterations in fish, which may affect some behavioral patterns. We evaluated the effects of water temperature on the aggressive behavior of male freshwater angelfish, Pterophyllum scalare. We subjected pairs to three water temperature conditions: low (23.8 ± 0.8°C), medium (27.9 ± 1.2°C), and high (31.7 ± 1.0°C), with eight repetitions each. We assessed latency to fighting, aggressive interaction frequency, and territorial defense. In low and high temperatures there was a reduction in aggressive behavior exhibitions in comparison to medium temperatures (P < 0.05). As a result, water temperature can influence aggressive motivation and territorial establishment, given that temperatures closer to species optima (27.9 ± 1.2°C) can favor social contests for an Amazonian ornamental cichlid species, P. scalare.

Determination of growth performance and some gastrointestinal traits of Angelfish (Pterophyllum scalare) fed with different levels of Digestrum P.E.P.

This survey was done in order to use of different levels of the herbal supplement Digestrum P. A. P. in freshwater Angel fish (Pterophyllum scalare) fry and its effect on some growth performance; microbial Flore and morphology of intestine. 120 fry (1.2±0.4g) were gathered in a Complete Randomize Design plane with 4 treatments fed on different levels of Digestrum (0, 1, 1.5 and 2 g/kg) each with 3 replicates for 60 days. The results showed that Digestrum had positive effects on final body weight, SGR and FCR so that in the treatment fed on 2 gr. The most final weight (6.8g±0.34), the best SGR (4.0±0.12) and the least FCR (1.1±0.22) were observed in the same treatment (p<0.05). The most number of Lactobacilli colonies, The best length of intestine villi (600.14+_15.44), villi across (105.14±2.18), and cript depth (55.2±2.10) were reported from this treatment too (p<0.05). Based on the results, it could be concluded that the herbal supplement Digestrum P. A. P. can improve performance and intestine bacterial flour in 2g/kg level of diet.

Embryonic and larval development in the freshwater angelfish &lt;em&gt;(Pterophyllum scalare)&lt;/em&gt;

The freshwater angelfish, Pterophyllum scalare like many other cichlids show parental care of embryos and larvae. This study was carried out to investigate the embryonic development of P. scalare, which shows biparental care and substrate brooding. During the study adult reproductive behavior and parental care was observed. Once the eggs were fertilized upon spawning, the early and later embryonic stages were observed, documented and various embryo length measurements were analyzed to characterize the developmental pattern in this species. Whole mounts and bone and cartilage measurements of acid free double stained larvae were analyzed to further understand the developmental rates in the hatched larvae. The developmental events were compared with those of other documented cichlid species as well as with the zebrafish, Danio rerio (Family Cyprinidae), which does not show parental care. After fertilization, cleavage division of the P. scalare embryo starts 1.30 hours post fertilization (hpf). On average, cleavage, blastula, gastrula, segmentation and pharyngula periods of embryogenesis are observed for approximately 3 ½, 11 ½, 9 ½, 36 and 12 hours respectively. Ultimately, P. scalare embryos hatched around 72 (hpf). Head Length, dorsal, caudal and anal fins show positive allometric growth while body depth and digestive tract show almost isometric growth. The study highlights that similar to a few other studied cichlids, P. scalare embryogenesis and larval development occur at a slower rate of development compared to D. rerio. In cichlids including P. scalare, parental care may allow these embryos the luxury of developing at a slower rate whereas the lack thereof for D. rerio embryos may necessitate faster development.

Effect of fasting on freshwater angelfish Pterophyllum scalare (Lichtenstein; Pisces: Cichlidae) development

We tested the effect of fasting on the development of juvenile freshwater angelfish (Pterophyllum scalare). The juveniles were subjected to different fasting periods (0, 3, 6, 9, 12, and 15 days of fasting). Fish from all treatments were fed for 30 days after the fasting period. No difference (P &gt; 0.05) was observed between treatments for final weight and length. There was a significant difference (P &lt; 0.05) in treatments 12 and 15 days fasting for liver and intestine weight. These results may prove that 12 and 15 days of fasting force juveniles to use energy reserves, and these adaptations may also represent a saving energy strategy. The fish subjected to treatments 6, 9, 12, and 15 days of fasting showed different vacuolization in hepatocytes from the ones subjected to 0 and 3 days of fasting (P &lt; 0.05). These results show that during the lack of feeding, juveniles (P. scalare) mobilizes energy stored in the liver. No difference (P &gt; 0.05) was observed between treatments for survival rate. However, the increase in the number of deaths from the eighth day of fasting may indicate that periods with more than 15 days of fasting could be fatal to this species during this life stage. According to our findings, it can be assumed that juvenile freshwater angelfishes have strategies (e.g. a decrease in liver and intestine weight) to resist 15 days of fasting.

Edwardsiellosis in freshwater angelfish (Pterophyllum scalare)

The freshwater angelfish (Pterophyllum scalare) with its many varieties is one of the most popular species in the ornamental market. The moribund freshwater angelfish individuals (20-25 g in weight) were sampled from an ornamental fish production facility to determine the cause of mortalities started immediately in fish without any other visible finding except the loss of appetite. The mortality rate in the population was as high as 50% within a week. Bacteriological samples were taken from internal organs for the identification of the causative agent. Hemorrhage in the eyes, loss of scales and skin depigmentation were the most obvious external finding in the moribund fish. Internally; the liver was pale, the spleen was enlarged and the intestinal walls were thinned. According to conventional biochemical and physiological tests and 16S rRNA gene sequencing, all isolated bacteria were identified as Edwardsiella tarda. The antimicrobial susceptibility test performed using the disk diffusion test showed that the E. tarda strains we obtained were sensitive to enrofloxacin, sulfamethoxazole with trimethoprim, furazolidone and flumequine but resistant to ampicillin and tetracycline antibiotics.

Use of eugenol for the anaesthesia and transportation of freshwater angelfish (Pterophyllum scalare)

This study aimed to evaluate the effectiveness of eugenol for the induction and anaesthesia recovery of freshwater angelfish juveniles, and to verify its effectiveness for transportation. Juveniles were exposed to different concentrations of eugenol: 0 (control), 10, 15, 20, 30, 40, 50 and 60 μL L−1 (equivalent to 10.6, 15.9, 21.2, 31.8, 42.4, 53.0 or 63.6 mg L−1). Afterwards, other fish were divided into two groups: sedated with 15.9 mg L−1 eugenol and non-sedated, and they were evaluated 4 and 7 h after transportation. The minimum effective concentration for sedation and anaesthesia occurred with 15.9 and 53.0 mg L−1 eugenol, respectively. The total ammonia was significantly higher in the control group than the sedated group 7 h after transportation. Blood glucose levels were significantly higher in the sedated fish in relation to the control group 7 h after transportation. The gill histopathology analysis and muscle glycogen levels were not influenced by eugenol or the time of transportation. It is concluded that 15.9 and 53.0 mg L−1 eugenol were effective concentrations for sedation and anaesthesia in juveniles, and that 15.9 mg L−1 eugenol has the potential to be used for the transportation of freshwater angelfish for up to 7 h.

Economic And Logistical Viability of Production of Freshwater Angelfish (Pterophyllum Scalare)

The Freshwater Angelfish stands out for being one of the most beautiful, best-selling and also most popular ornamental fish of tropical waters. Its cultivation is concentrated in the southeastern and southern regions of Brazil, so reproduction of this species in other areas can become a profitable venture. The present study analyzed the economic viability of the cultivation of the Freshwater Angelfish, Pterophyllum scalare, in a water recirculation system. To measure the market demand, an interview was conducted with the main tenants in the industry, adding to the estimate. The profitability of the venture was 2,65% in the first year and 11,95% in the second to the tenth year and the payback rate was 38 months or 3 years and 2 months. Small-scale farming proved to be economically viable, presenting attractive profitability indicators compared to other aquaculture enterprises.Â

Efficacy of Benzocaine, Eugenol, and Menthol as Anesthetics for Freshwater Angelfish

For the production and commercialization of ornamental fish species, it is indispensable to collect biometric data that facilitate the selection of animals for trade and genetic improvement of the stock. However, during the handling process, fish receive more stress if proper anesthetics are not used. Thus, application of appropriate anesthetics is an important tool for minimizing stress in animals. The objective of this study was to determine the effective concentrations of benzocaine, eugenol, and menthol for achieving anesthesia in Freshwater Angelfish Pterophyllum scalare and to develop induction and recovery response curves for different concentrations of these anesthetics. In total, 75 fish were exposed to five concentrations of the three anesthetics in a completely randomized design: benzocaine at 60, 85, 110, 135, and 160mg/L; eugenol at 40, 80, 120, 160, and 200mg/L; and menthol at 50, 75, 150, 200, and 250mg/L. Each concentration (5fish/concentration) consisted of five replicates, with each replicate represented by a single fish. The results indicated that the tested substances met the criteria of anesthetic efficiency. The effective concentrations of benzocaine, eugenol, and menthol for the anesthesia of Freshwater Angelfish were identified as 89.25, 90.6, and 92.1mg/L, respectively.

Effects of Green Tea Extracts on freshwater angelfish, Pterophyllum scalare Growth Performance

The study was conducted to investigate the effects of dietary green tea extract (GTE) supplementation in diet on growth performance, feed utilization and biometric indexes in freshwater angelfish, Pterophyllum scalare. The fish (mean body weight, 2.61±0.01 g) were fed fish meal diets that included 0% (control), 2.5 and 5% GTE for 8 weeks. The results showed, the addition of green tea extract did not have a positive effect on growth performance and other variables. Addition of green tea extract did not change the amount of viscerosomatic index and hepatosomatic index.

Description of growth and body composition of freshwater angelfish (Pterophyllum scalare) by Gompertz model

ABSTRACT The objective of this study was to describe the growth of freshwater angelfish (Pterophyllum scalare) using the Gompertz model, determining the relative growth and allometric coefficients of body components in relation to body weight and protein weight. Six hundred animals were grown until 233 days of age. Data on chemical composition (water, lipid, protein, and ash) and weight measurements were obtained each 30 days. The Gompertz growth equation was used to analyze chemical allometry and to estimate growth parameters. [...]