Latest Research Ichthyology: September 2021

A Phylogenomic Perspective on the New Era of Ichthyology

With more than 24,000 extant species, the Actinopterygii is the most diverse group of vertebrates. This astonishing diversity represents not only an underexploited resource for research focused on these fishes but also a source of valuable information for comparative biology and medical science. Although the technical advances in morphology concomitant with revolutionary phylogenetic concepts have presented many challenges in ichthyology for the past half-century, spectacular progress in DNA technology provides other opportunities for research using multiple-gene or genomic data for the study of biological questions, particularly those related to the evolution of fishes. In this article, we discuss how ichthyology is changing in this new era, and how the emerging phylogenomic approach has been used to study species diversification in relation to gene and genome duplications and to resolve the complex evolutionary history of ray-finned fishes. [1]

Integrated ichnology and ichthyology of the Oligocene Menilite Formation, Skole and Subsilesian nappes, Polish Carpathians: A proxy to oxygenation history 

The anoxic, mostly black or brown fine-grained sediments of the Menilite Formation (Oligocene–Early Miocene) in the Skole and Subsilesian nappes contain thin layers of bioturbated green or grey-green mudstones, some of which contain the trace fossils Halimedides annulataMultina isp., Palaeophycus ?tubularis, ?Planolites isp., Rhizocorallium isp., Trichichnus isp. and Zoophycos isp. The Trichichnus–Palaeophycus–(MultinaHalimedides)–Rhizocorallium suite indicates an increase in oxygenation of sediments. The contribution of different ecological groups of fishes, including epipelagic, bathypelagic, benthopelagic, neritic and reef, and demersal taxa changes significantly through the Menilite Formation. The absence or reduction of bathypelagic fishes points to anoxia in the water column. The combination of ichnological and ichthyological data and incorporation of data on benthic foraminifers allowed a reconstruction of oxygenation changes in the sediment and water column during deposition of the Menilite Formation. Total anoxia at the sea floor and in the water column, attributed to a combination of thermo-stratification and extremely high organic productivity, occurred only during the period reflected by ichthyofaunal Zone IPM2 (middle part of the NP23 Zone). Anoxia restricted to the basin floor or upper slope, related in part to upwelling, occurred during sedimentation of the upper part of the Menilite Formation. [2]

How far has Neotropical Ichthyology progressed in twenty years?

Studies on the diversity, taxonomy, phylogeny, and biogeography of Neotropical Fishes have thrived over the twenty years that have elapsed since the first symposium on their phylogeny and classification in Porto Alegre, Brazil. Here, we review recent advances in the study of Neotropical fishes and assess the known diversity of freshwater species in that region. 6,255 valid freshwater species have been discovered in the Neotropics so far, and we estimate that over 9,000 species will be known when the inventory is complete. We also summarize the events of the second Symposium on Phylogeny and Classification of Neotropical Fishes that took place last year in Londrina, Brazil. Along with invited talks on the biodiversity of all major groups of Neotropical fishes, a series of presentations on the development of fish collections, and numerous contributed talks, the meeting included a special session to honor Dr. Richard Vari, who was one of the most prolific and beloved members of our community. [3]

Monthly Frequency Occurrence, Sex-ratio, Length-weight Relationship and Condition Factor of Native Fishes Caught in a Tropical Floodplain Rivers of Cameroon, Central Africa 

Aims: To evaluate the aquaculture potential of the native fishes from the Mbô Floodplain (MF) Rivers for their domestication and preservation the genetic diversity.

Study Design: Descriptive research.

Place and Duration of Study: Laboratory of Applied Ichthyology and Hydrobiology, Department of Animal Productions, Faculty of Agronomy and Agricultural Sciences, the University of Dschang-Cameroon, between October 2008 and October 2009.

Methodology:A total of 449 fishes measured 11.50 to 50.50cm (mean: 24.60±5.70 SDcm) total length (TL) and 8 to 1300g (mean: 169.18±111.01 SDg) total weight (W), were used for the analysis. Taxonomic identification was performed. The TL and the W were measured using an ichtyometer and electronic balance respectively. The sex of the fish was determined by macroscopic examination of genital papilla or the gonads after dissection. Fishes were counted by species, sexes and months. For data analysis, descriptive statistics, Chi-square test, t-test, general linear model, and the statistical significance of r2 were performed using SPSS 20.0 software at 5% and 1% significance levels.

Results: Four families with four species were determined: Clariidae (Clarias jaensis), Cyprinidae (Labeo camerunensis and Labeobarbus batesii), Cichlidae (Tilapia camerunensis). All fish species were a higher size. The allometry coefficient b ranged from 2.01 (Labeo camerunensis) to 3.12 (C. jaensis) (mean=2.58±0.50 SD). All species sampled have more females than males indicate the number of both females and males for possible relative sex percentages. Fish species shows positive and negative allometric growth. The higher K factor was recorded in the Cichlidae family and the lower in Clariidae. However the majority of fish species showed a good well-being.

Conclusion:All fish species show a positive aquaculture potential. Then they could be domesticated and preserved genetic diversity. This study, however, need further work to validate reliability. [4]

Feeding Habits of the African Carp Labeobarbus batesii (Pisces: Cyprinidae) from the Mbô Floodplain Rivers

Aims: The African cyprinids were not yet used in aquaculture. For domestication and preservation of the African carp Labeobarbus batesii, aspects of feeding habits  in term of its aquaculture potential proves necessary.

Place and Duration of Study: Laboratory of Applied Ichthyology and Hydrobiology, Department of Animal Productions, Faculty of Agronomy and Agricultural Sciences, University of Dschang, Cameroon, from May 2008 to October 2009.

Methodology: 318 fish samples (17 cm to 93.70 cm, means 25.47±4.47 cm of total length; 40 g to 6000 g, means 187.41±125.69 g for total weight) were collected monthly from artisanal fishermen in the Mbô Floodplain Rivers (MF). After fish’s dissection, guts were immediately removed and dissected, empty and replete guts were counted. Food items were identified to lowest possible taxon. They were counted under a stereoscopic binocular microscope in petri dishes. The microscopic food organisms were examined under a light microscope and the identified organisms were counted using Thoma lam. Three indices were used for gut contents analysis: Gut vacuity index, Frequency of occurrence and Percentage of abundance. Descriptive statistics, analysis of variance (ANOVA) and the generalized linear model at P = 0.05 and P = 0.001 probability level were used.

Results: Gut vacuity index was very low (11.95 %), and varied between seasons, zones, sexes and maturity state. Seven taxonomic groups were observed in L. batesii guts: plant foods (macrophyta and algae) are predominant both in frequency and abundance in the diet than animal foods (insects, CrustaceansNematodaProtozoa and other invertebrates).

Conclusion: Labeobarbus batesii consumes many varieties of animal and plant organisms. This species is benthopelagic, detritivorous and omnivorous with a preference for plant material.  [5]


[1] Chen, W.J. and Mayden, R.L., 2010. A phylogenomic perspective on the new era of ichthyology. Bioscience60(6), pp.421-432.

[2] Kotlarczyk, J. and Uchman, A., 2012. Integrated ichnology and ichthyology of the Oligocene Menilite Formation, Skole and Subsilesian nappes, Polish Carpathians: A proxy to oxygenation history. Palaeogeography, Palaeoclimatology, Palaeoecology331, pp.104-118.

[3] Birindelli, J.L. and Sidlauskas, B.L., 2018. Preface: How far has Neotropical Ichthyology progressed in twenty years?. Neotropical Ichthyology16.

[4] Tiogué, C.T., Zango, P., Efolé, T.E., Kenfack, M., Tekwombuo, J., Tekou, G., Domwa, M., Tomedi, M.T.E. and Tchoumboué, J., 2014. Monthly frequency occurrence, sex-ratio, length-weight relationship and condition factor of native fishes caught in a tropical floodplain rivers of Cameroon, Central Africa. Journal of Scientific Research and Reports, pp.2864-2874.

[5] Tiogué, C.T., Tomedi, M.T.E., Nguenga, D., Tekou, G. and Tchoumboué, J., 2014. Feeding Habits of the African Carp Labeobarbus batesii (Pisces: Cyprinidae) from the Mbô Floodplain Rivers. Advances in Research, pp.757-765.

Use of Biomass as a Raw Material for Energy Production

The purpose of this research is to explain why biomass is used as a raw material for energy generation. The significance of biomass is defined, as well as why it is a potential energy source. The use of biomass as an energy source is based on the creation of heat energy during burning. During biomass burning, the solar energy absorbed and stored by plants is released as heat energy. The chemical composition, percentage of extractives, moisture content, ash content, and density of forest biomass are all factors that influence its energy value (heating value). The literature review stated the calorific values of several chemical components (cellulose, lignin, extractives), forest species (Softwoods, hardwoods), and different portions of the same tree (wood, bark, leaves, branches) as numerical facts. On a dry weight basis, softwoods have more energy than hardwoods due to increased lignin content and the presence of more resinous extractives. Finally, the benefits and drawbacks of biomass as an energy source are discussed: biomass is renewable and environmentally beneficial, but it has a poor efficiency. However, because of rising oil prices and the pollution generated by its combustion, this problem is progressively dissipating, encouraging a greater use of biomass as an energy source.

Author (S) Details

Tsatiris Michael
Department of Forestry and Management of the Environment and Natural Resources, Democritus University of Thrace, Orestiada 68200, Greece.

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Role of Surface Carbohydrates in the Adaptation of Fasciola hepatica to the Intermediate Host Galba truncatula

The fluke of the liver Fasciola hepatica is a parasite that has a significant detrimental influence on the livestock sector and is also an issue for humans in various parts of the world. Lymnaeid snails serve as an essential intermediary host for F. hepatica’s multiplication and act as parasite carriers. However, the particular mechanisms through which F. hepatica has adapted to thrive in its sensitive invertebrate host are unknown.

Surface carbohydrates play an important role in cell-to-cell contacts, such as the parasite-snail relationship. Carbohydrate-binding molecules recognise them, and this is the start of the mechanisms by which parasites are able to use the specific snail host for development and proliferation.

Using lectin labelling, our team was able to identify the carbohydrates linked to the snail-pathogenic larval stages of F. hepatica, as well as the tissues of Galba truncatula, the major fasciolosis transmitter. The significance of surface carbohydrates in the parasite’s adaptation to this particular host, such as snail identification, miracidial-to-sporocyst transformation, and immune evasion, has also been investigated.

This review highlights our findings and sheds light on the critical function of surface carbohydrates in interactions with carbohydrate-binding molecules, indicating that these interactions are one of the determining elements in F. hepatica transmission by the particular vector G. truncatula.

Author (S) Details

Katya Georgieva
Department of Animal Diversity and Resources, Bulgarian Academy of Sciences, Institute of Biodiversity and Ecosystem Research, Acad. G. Bonchev St., Bl. 25, 1113 Sofia, Bulgaria.

Veselin Nanev
Department of Experimental Parasitology, Bulgarian Academy of Sciences, Institute of Experimental Morphology, Pathology and Anthropology with Museum, Acad. G. Bonchev St., Bl. 25, 1113 Sofia, Bulgaria.

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Study on Increase in PKCα Activity during Heart Failure Despite the Stimulation of PKCα Braking Mechanism

Heart failure (HF) is characterised by a reduction in cardiac contractility. During heart failure, a mild treatment target that improves contractile function without desensitising the -adrenergic system could enhance cardiac contractility and possibly survival. Inhibiting the activity of protein kinase C (PKC) may meet the criteria for a therapeutic target with fewer systemic side effects while yet increasing contractility in HF patients. During HF, PKC activity has been reported to rise. The fact that this increase in PKC activity is accompanied by up-regulation of a molecular braking mechanism is confusing.

Despite the presence of a molecular braking mechanism, I want to see if PKC activity can be boosted and maintained during HF.

Methods and Results: I show that in cardiomyocytes, local diacylglycerol (DAG) signalling is regulated by a two-compartment signalling system using a computational approach. These findings suggest that local DAG signalling equilibrium is compromised after a severe myocardial infarction (MI). When this equilibrium is disrupted, PKC, a critical molecular target connected to LV remodelling and defective filling and ejection in mammals, is activated over an extended period of time. This research also explains how DAG homeostasis is maintained throughout normal systolic and diastolic heart activity.

Conclusions: During Ang II-induced heart failure, I devised an unique two-compartment computational model for regulating DAG homeostasis. This model could be used to investigate the mechanisms of DAG signalling control in heart failure. The model can also be used to find new therapeutic targets for heart failure patients, with the goal of enhancing their quality of life.

Author (S) Details

Naveed Aslam
BioSystOmics 4424 Jim West Street, Bellaire, Texas 77401, USA.

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Studies on Sexual Dimorphism in a Cross River Ecotype Local Chicken – Rose Comb (Gallus gallus domesticus

In Cross River, researchers looked into sexual dimorphism in the local chicken (Gallus gallus domesticus)-Rose Comb. The influence of sex on body weight (BW), body length (BL), body girth (BG), thigh length (TL), shank length (SL), and keel length (KL) was measured fortnightly for twelve (12) weeks on sixty (60) male and female Gallus gallus domesticus chickens. To confirm the relative contribution of each characteristic to overall dimorphism, the Sexual Size Dimorphism Index (SSDI) and Sexual Dimorphism Index (SDI) were used. BW had SSDI and SDI values of 1.61 and 61 percent, TL had 1.26 and 26.52 percent, SL had 1.23 and 23.81 percent, BL had 1.22 and 21.50 percent, BG had 1.18 and 18.20 percent, and KL had 1.17 and 17.94 percent. Stepwise discriminate analysis was used to find the best feature for predicting sex, yielding Wilk’s Lamda values of BW(0.471); TL(0.452); SL(0.401); BL(0.283); BG(0.272); and KL(0.471) (0.271). At week 6, all measured parameters exhibited significant (p0.05) differences, with mean BW, BL, BG, SL, KL, and TL of 300.01 and 253.24; 22 and 18.62; 5.20 and 3.98; 4.60 and 3.50; 5.50 and 3.90; 13.10 and 11.20 for both male and female birds, respectively. These findings show that sexual dimorphism exists in all morphometric traits in favour of the male, with BW being the most dimorphic. The research will also aid in the selection of Gallus gallus domesticus for improved meat production and will address the issue of sex discrimination during mating selection before sexual maturity.

Author (S) Details

Hannah Edim Etta
Biological Sciences Department, Cross River University of Technology, Calabar, Cross River State, Nigeria.

Kogbara, Henry Barizigakol
Department of Genetics and Biotechnology, University of Calabar, Calabar, Cross River State, Nigeria.

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Hosts of the Parasitoid Pachycrepoideus vindemmiae (Rondani) (Hymenoptera: Pteromalidae) for Medical, Veterinary and Economic Importance Collected in the State of Goiás, Brazil

Pachycrepoideus vindemmiae (Rondani) (Hymenoptera: Pteromalidae) is a solitary parasitoid that feeds on Diptera from the families Anthomyiidae, Calliphoridae, Cecidomyiidae, Drosophilidae, Lonchaeidae, Muscidae, Phoridae, Piophilidae Pachycrepoideus vindemmiae is a parasitic Diptera parasitoid that feeds on Calliphora, Lucilia, Hylemya, Drosophila, Rhagoletis, Paratheresia, Anastrepha, Ceratitis, Phormia, Phaenicia, Sarcodexia, Zaprionus, Ornidia, Megaselia, Synthesiomyia, and Haematobia. This species has a wide range of distribution; it has been found in North America, Canada, Africa, and various Latin American, Asian, and European countries. The parasitoid P. vindemiae is studied in this book chapter in terms of its hosts, development in diverse substrates, geographical distribution, taxonomy, biology, types of traps and collecting methods, and an experimental research.

Author (S) Details

Carlos Henrique Marchiori
Instituto Federal Goiano, Goiás, Brazil.

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Determination of Correlationship between Hydrological Residence Time and Phytoplankton Dynamics in Lake Kinneret, Israel BP2436

The goal of this work is to try to link phytoplankton dynamics to hydrological features, and to use the nutrient as a speculative instrument to do so. Water Residence Time is the hydrological trait’s chosen parameter, which is evidently integrated throughout the full water balancing frame. The dynamics of phytoplankton (Peridinium, Cyanophyta, Chlorophyta, and Diatoms) in Lake Kinneret were compared to hydrological factors throughout time. The algal biomass distribution was shown to be associated with hydrological characteristics. As a result, Residence Time, the best representor of the hydrological feature, is suggested as a critical parameter governing algal dynamics.

Author (S) Details

Moshe Gophen
Migal-Scientific Research Institute, Kiryat Shmone, Israel.

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Pathological Correlates to Prolactin and Growth Hormone

Prolactin (PRL) and Growth Hormone (GH) are important regulators of body growth and metabolism. The secretion and activities of GH and PRL are influenced by a variety of variables at various levels. These hormones begin their biological effects by attaching to their respective membrane-bound receptors for GH and PRL (GHR and PRLR). Changes in target tissue sensitivity are a feature of several hormone systems. The number of specific receptors and the duration of receptor triggered intracellular impulses are important determinants in hormone sensitivity. For example, tyrosine phosphorylated intracellular proteins are inactivated by tyrosine phosphatases or proteasomal degradation, which is a recurring motif. This chapter focuses on two distinct proteins, Suppressors of Cytokine Signaling2 (SOCS2) and Tuberous Sclerosis Complex2 (TSC2), which have distinct effects on JAK-STAT and mTOR activation. The SOCS2-dependent increase in GH and PRL sensitivity in diabetes and other disorders such as hormone-sensitive malignancies raises questions about the significance of changed GH/PRL sensitivity in addition to conditions involving over- or under-production of these hormones. It could be used to target GH/PRL sensitivity in the future if conventional hormone therapy fails due to decreasing sensitivity. There are many gaps in our understanding that need to be addressed, and this may be especially true for PRL, where fresh research suggests that the hormone’s activity profile in humans differs from that in animals.

Author (S) Details

Amira Al Kharusi
College of Medicine, Sultan Qaboos University (SQU), Oman.

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Life as Interplay of Information and Matter

By changing the alphabet and/or encoding, any sequence can be turned into an equivalent one. As a result, information should be described as the equivalence class among sequences with regard to such changes, an abstract entity, rather than a specific sequence. Its ‘information message,’ defined as the shortest binary sequence in this class, whose length quantitatively measures the information, can be used to describe it. Information connects the abstract and the concrete by requiring a physical medium to carry any sequence. Random symbol errors are caused by perturbations in the physical world, whereas information can command the assembly of physical objects by the computer. the task Because old sections of the genome are better preserved, genomic error-correcting codes are constructed up of nested component codes. This model takes into account core life characteristics such as the requirement for successive generations, the existence of discrete species with hierarchical taxonomy, and the evolution of complexity. Enzymes regulate gene transcription and translation into polypeptidic chains, which then fold into proteins. As a result, a feedback loop is formed, which is referred to as “semantic” since it implements the genetic code that explains the meaning of the genes. When the door is shut, As a result of its semantic specificity and redundancy, it has the power to remedy errors. As a result, stopping semantic feedback loops does not stop evolution: new structures can be added with better error resilience. Regeneration failure is uncommon, but it does result in a vastly altered genome, which can lead to the emergence of a new species if the phenotype it specifies survives Darwinian selection. It is offered a scenario for the origin of semantic feedback loops (and thus, possibly, life).

Author (S) Details

Gerard Battail

E.N.S.T., Paris, France

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Study on Revisiting Sacral Hiatus

The caudal opening of the sacral canal is known as the sacral hiatus. Through the sacral hiatus, caudal epidural anaesthesia is administered for a variety of therapeutic and diagnostic procedures. In the literature, there is a 25% failure rate for caudal epidural blocks. This procedure’s high failure rate could be due to the sacral hiatus’s various anatomical features. To reduce the failure rate of the sacral hiatus, clinicians must understand the anatomical variations in shape, size, level of apex, and base. caudal epidural block. The anatomical features of sacral hiatus are of immense value to orthopaedic surgeons, obstretricians, paediatricians, anaesthecians and anatomists. Aim of study is to update and consolidate the information on sacral hiatus as this updated and consolidated information on sacral hiatus in this chapter will serve a ready reference for future researchers and clinicians.

Author (S) Details

Prof. Rajani Singh

Department of Anatomy, UPUMS, Saifai Etawah, 206130, India.

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