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PubMed1978

[Findings in quality controls of ocean fish in the Siegen district].

In quality tests on traded sea-fish, 30 fresh fish- and 20 quick-frozen fish specimens were tested for their TVB-N content, TMA-N content, as well as for TMAO-N, and were subjected to a sensorial test. Equal portions of codfish- and perch fillets were tested. According to the chemical analytic data, 13 specimens of the fresh fillets proved to be unobjectionable commercial merchandise 17 specimen had to be eliminated as being spoiled, since part of the above values for TVB-N and TMA-N had been considerable exceeded. The results differ enormously between the two species of fish. The perch fillets showed a significant better quality condition than the specimens of codfish. In the sensorial test the objective total result was confirmed in the main. On the basis of the chemical findings one specimen of codfish out of the deep-frozen fillets had to be objected. 16 fillet-specimens could sensorially be approved as being commercially marketable, 4 were tested not for sale. With codfish showing considerable better results than perch.

Animals↗
PubMed1978

Relation between myelin sheath thickness and axon size in spinal cord white matter of some vertebrate species.

The relation between number of myelin lamellae and axon size in the CNS was examined by electron microscopy of spinal cord white matter fibres in different vertebrate species (cat, rabbit, guinea pig, rat, mouse, frog and perch). The results show that the number of myelin lamellae increases with increasing axon size in a non-linear fashion. Below an axon size of 4--5 micron the relation follows a fairly straight line but above this size rectilinearity is lost. The mouse and the frog differ from the pattern shared by the other animals. In the mouse the lamellar number increases more slowly with axon size and the relation is close to linear. In the frog the number of lamellae increases very slowly with axon size and the relation is markedly curvilinear. Measurements of the myelin repeating period show that in the mammals and the frog the average period of thick sheaths is about 85% of that in thin sheaths, in accordance with previous findings in the cat. In the perch a clearcut difference in this respect between thick and thin sheaths is not found. Calculations of the g-ratio on the basis of the findings indicate that it increases with increasing fibre size. This is most pronounced in the perch and the frog in which the g-ratio for the largest fibres far exceeds the functionally optimal value defined in theoretical analyses on impulse propagation.

Animals↗
PubMedDate not supplied

Distribution of total and fecal coliform organisms from septic effluent in selected coastal plain soils.

Distribution of total and fecal coliform bacteria in three Atlantic coastal plain soils in Virginia were monitored in situ over a 3-year period. The soils studied were Varina, Goldsboro, and Beltsville sandy loams. These and similar soils are found extensively along the populous Atlantic seaboard of the United States. They are considered only marginally suitable for septic tank installation because the restricting soil layers result in the subsequent development of seasonal perched water tables. To determine both horizontal and vertical movement of indicator organisms, samples were collected from piezometers placed at selected distances and depths from the drainfields in the direction of the ground water flow. Large reductions in total and fecal coliform bacteria were noted in the perched ground waters above the restricting layers as distance from the drainfield increased. These restricting soil layers appear to be effective barriers to the vertical movement of indicator organisms. The reduction in the density of the coliform bacteria above the restricting soil layers can probably be attributed to dilution, filtration, and dieoff as the bacteria move through the natural soil systems.

Escherichia coli↗
PubMed1978

Development of the compound eyes of dragonflies (Odonata). III. Adult compound eyes.

The distribution of ommatidial diameters and interommatidial angles, as determined by measuring the angles between the optic axes of adjacent ommatidia, are mapped across the surface of the compound eyes of a variety of species selected for different adult behaviors, developmental histories, and taxonomic positions. The size of the visual fields, prey capture foveas, foveas composed of large dorsal ommatidia, and other specializations in the numbers of ommatidia that view various directions in the visual field are discussed in relation to adult behavior. Advanced species have less resemblance between their larval and adult eyes than primitive species. In contrast to their larvae, adults increase the monocular resolution of each eye at the expense of binocular vision. Most species have foveas which view in approximately the anterior direction, instead of in a region of binocular overlap, and many species have foveal bands which view along the horizon. Some advanced perching species, which approach their prey and other odonates from below, have an additional vertical foveal band that views along a vertical plane from the anterior direction to a more dorsal direction. The most unusual foveal band is seen in active flying species. The large dorsal ommatidia of the migratory Anax junius, which cover approximately one third of the eye surface, view a narrow region of the visual field that extends along a plane from the most lateral direction of one eye to a dorsal direction, and continues without interruption to the most lateral direction of the other eye.

Animals↗
PubMed1976

Toxicity of natural pyrethrins and five pyrethroids to fish.

The toxicity of natural pyrethrins and five pyrethroids was determined with coho salmon (Oncorhynchus kisutch), steelhead trout (Salmo gairdneri), fathead minnow (Pimephales promelas), channel catfish (Icatlurus punctatus), bluegill (Lepomis macrochirus), and yellow perch (Perca flavescens). The 96-hour LC50's in static tests at 12 degrees C ranged from 24.6 to 114 mug/l of natural pyrethrins and from 0.110 to 1,140 mug/l of pyrethroids. Two pyrethroids, RU-11679 and SBP-1382 (R), were over 10 times more toxic than pyrethrum extract in the flow-through tests. Coldwater species of fish were more sensitive than warmwater species to all the compunds. Temperature (12-22 degrees C) influences the toxicity of natural pyrethrin and the pyrethroids. The natural pyrethrin was more toxic to fish in pH 6.5 than in pH 9.5 water, but the toxicity of pyrethroids was not influenced in the pH range. The two most toxic pyrethroids, RU-11679 and SBP-1382, Were deactivated more rapidly in water solutions than natural pyrethrins, S-bioallethrin, dimethrin, and d-trans allethrin.

Animals↗
PubMed1978

Acute toxicity of hydrogen cyanide to freshwater fishes.

Acute toxicity of hydrogen cyanide was determined at various temperatures from 4 degrees to 30 degrees C and oxygen concentrations of 3.36 to 9.26 mg/L on different life history stages of five species of fish: fathead minnow, Pimephales promelas Refinesque; bluegill, Lepomis macrochirus Rafinesque; yellow perch, Perca flavescens (Mitchill); brook trout, Salvelinus fontinalis (Mitchill); and rainbow trout, Salmo gairdneri Richardson. Median lethal threshold concentrations and 96-hr LC50's were established by flow-through type biassays. Acute toxicity varied from 57 microgram/L for juvenile rainbow trout to 191 microgram/L for field stocks of juvenile fathead minnows. Juvenile fish were more sensitive at lower temperatures and at oxygen levels below 5 mg/L. For most species juveniles were most sensitive and eggs more resistant.

Aging↗
PubMed2026

Brain-wide spontaneous neural avalanches: Definition, functional dynamics and cognitive relevance.

Although spontaneous activity is ubiquitous across multiple spatiotemporal scales, its functional organization and cognitive relevance remain poorly understood. Following the classic neuronal avalanche framework, a spontaneous avalanche is defined as consecutively active frames separated by inactive time bins. Hence, multiple distinct avalanches may be considered as one avalanche, thereby ignoring their spatial and temporal distinguishability. Furthermore, group-level power-law fitting of such neural avalanches is often performed to evaluate brain criticality (referring to a system perched between order and disorder) due to the limited recording length of macroscale neuroimaging (such as functional magnetic resonance imaging), and the functional representation of brain-wide neural avalanches is largely unexplored. To address these issues, we proposed large-scale neural avalanches as a single, spatially consecutive cascade pattern and further investigated their functional dynamics, network propagation, and association with task-evoked activity. Compared with the conventional inactive-bin definition, our current approach is more favorable to power-law fitting of avalanche size and duration distributions at the individual level. We also demonstrated that participants whose brain activities were close to the critical point tend to have higher cognitive abilities. Notably, the ratio of neural avalanches that evolved from primary sensory to association networks negatively correlated with cognitive abilities. Moreover, the geometric distance between low-dimensional representations of task-evoked activity and spontaneous avalanches was associated with behavioral performance. This study not only provides a promising avenue for measuring avalanche criticality based on human whole-brain neuroimaging, but also suggests that spontaneous neural avalanches and their low-dimensional representations contribute to human cognitive abilities.

Humans↗
PubMed2026

Evolutionary history of Aotearoa New Zealand's extinct mātuhituhi | bush wren.

The reconstruction of ecosystem responses to past climate change has historically focused on large vertebrates. In contrast, small vertebrates with potentially stricter habitat preferences have been neglected in ancient DNA studies despite their potential utility as proxies for inferring geographic and temporal changes in habitat. Aotearoa New Zealand's acanthisittid wrens are a speciose group of tiny perching birds, including the mātuhituhi | bush wren (Xenicus longipes ssp.). Despite its relatively recent extinction in the 1970s, very little is known about this enigmatic bird. Here we sequence mitochondrial genomes and nuclear ultra conserved genomic elements from 32 historical bush wren specimens to reconstruct their evolutionary history. We also genetically sex specimens and reanalyse their plumage to reconstruct aspects of bush wren plumage variation. Our analyses suggest North and South Island bush wren populations diverged 2.6 million years ago when narrowing and closure of Plio-Pleistocene seaways allowed colonisation of new habitats, followed by rapid glaciation-driven diversification of South Island populations 470,000-94,000 years ago. Genetic sexing allowed an accurate reconstruction of ontogenetic, sexual, and geographic variation in plumage. Our multidisciplinary data supports recognition of North and South Island populations as separate species, and the description of a new subspecies X. longipes perditus subsp. nov. This research shows how ecosystems can buffer against the impacts of climate change up to an ecological tipping point, which has important lessons for conservation management in a fast-changing world.

Acanthisittidae↗
PubMed1979

Calcium, magnesium and the conformation of parvalbumin during muscular activity.

The conformation of perch parvalbumin in the Ca-, Mg- and metal-free state was studied by intrinsic fluorescence, trypsin susceptibility, thiol titration and circular dichroism. The data reveal that Ca-parvalbumin has a more compact structure than the metal-free protein, with a high alpha-helical content and a buried thiol. No difference in conformation could be detected between Mg- and Ca-parvalvumin, indicating that the Ca-Mg exchange that may take place during muscular activity is accompanied by little or no structural changes. Furthermore, recently published kinetic parameters can now be interpreted as meaning that, during the contraction-relaxation cycle, parvalbumin often stays in the Mg-form instead of switching to the Ca-form which is predominant in vitro.

Calcium↗
PubMedDate not supplied

[New species of parasitic infusoria of the family Urceolariidae].

Three new species of Ciliata of the family Urceolariidae were found as follows: Paratrichodina voikarensis sp. n. on the gills of Coregonus nasus and C. peled; P. uralensis sp. n. on the gills of the sterlet and Trichodina percae sp. n. in the nasal cavities of the perch. Figures and descriptions of the new species are given.

Animals↗
PubMed1976

[Conditioning of the avoidance to the contact call in the red face lovebird (Agapornis roseicollis, Aves, Psittacidae)].

Two experiments were run on 10 lovebirds to test the reinforcing effect of the social call in an operant conditioning task. In the first experiment, the reinforced behavior (perching) which provoked the occurence of the call decreased. In the second experiment, where the same behavior stopped the continuous emission of the call, the behavior increased. This behavior may results from an avoidance to the call recorded from a lovebird which do not belong to the group of our experimental birds.

Animals↗
PubMed1979

[Heme binding by the serum proteins of fish].

Starch gel and disc electrophoretical results about heme binding of serum proteins of fishes (Pike, perch, bream) are reported on. Metheme albumin binding and a hemopexin polymorphism could be detected in all species of the fishes. The problems of differentiation between heme and hemoglobin binding are discussed.

Animals↗
PubMed1979

Organochlorine pesticide residues in animals of Tasmania, Australia-1975-77.

Animals taken in Tasmania including duck (Anas superciliosa), eel (Anguilla australis), English perch (Perca fluviatilis), white-faced heron (Ardea pacifica), brown trout (Salmo trutta), European starling (Strunus vulgaris), cat (Felis cattus), cormorant (Phalacrocorax sp.), mutton bird (Puffinus tenuirostris), Tasmanian devil (Sarcophilus harrisii), rainbow trout (Salmo gairdnerii), Tasmanian raven (Corvus mellori), tench (Tinca tinca), and quail (Coturnix sp.) were sampled for p,p'-DDE, pp,p'-TDE, p,p'-DDT, lindane, dieldrin, and hexachlorobenzene. Pesticide residue levels exceeded 0.1 ppm in at least one animal from each area and in the majority of animals sampled from all areas. Pesticide sources could not be determined, partly because migratory species such as ducks, mutton birds, cormorants, and eels may have ingested pesticides outside of Tasmania.

Animals↗
PubMedDate not supplied

[Fatty acid make-up of the muscle tissue lipids of ocean fish].

Consequent upon the results of investigating fatty acids composition in the tissue lipids of a number of marine fish (marmoreal and green nototenia, merow, stavrida, klykach, lufar, marine perch and marine bream) of different degrees of fatness there were ascertained substantial differences in the correlation of basic acid components and the nutritional value of the lipids. A comparison between the overall lipid content and the quantity of highly unsaturated acids enabled it to disclose a possible relative resistance of the studied fish to the oxidative lipids decay.

Animals↗
PubMedDate not supplied

[Problem of the infertility of hybrids of the muscovy (Cairina moschata L.) and the domestic duck (Anas platyrhynchos domestica)].

Analysis of blood serum proteins electrophoretic spectra for perching and domestic ducks resulted in revealing interspecific differences of prealbumin and transferrin types showing incomplete identity of loci in analogous sites of some homologous chromosomes in the hybridizants. This confirms the genetic nature of sterility in this crossing combination hybrids whose blood serum proteins electrophoretic spectrum displays a complex hybrid phenotype.

Animals↗
PubMed1978

Effect of hormones and pharmacological drugs on the blood of Anabas testudineus (Bloch).

Effect of different gonadal steroids, hydrocortisone, catecholamines and antithyroidal agent on certain haematological parameters in an air breathing fish, Anabas testudineus (Bloch) commonly known as climbing perch, have been made. The treatment of hydrocortisone, adrenaline, noradrenaline and testosterone brings about a significant increase in RBC counts (polycythemia), Hb content and PCV values as compared to control which were subjected to the treatment of normal saline. Males were more susceptible to the treatment of hydrocortisone, catecholamines than females. Ovocyclin, Duogynon forte and Fertyl treatments bring about anaemia in this fish, i.e. a decrease in RBC number, Hb content and PCV was clearly marked out. Females were more susceptible to Fertyl than males. Lutocyclin failed to bring any significant changes in these blood parameters. Though the treatment of thiouracil could not bring about significant changes in different blood parameters, a tendency of increase in RBC counts, Hb content and PCV was observed. The absolute values for different blood parameters have also been calculated. Possible reason and the mechanism of such changes in different blood parameters are discussed in detail.

Animals↗
PubMed1979

Patterns of purine nucleotides in fish erythrocytes.

1. The purine nucleotides were determined in the whole blood of 9 fresh water teleosts and 2 marine selachians. 2. GTP and ATP accounted for 88-99% of the total erythrocytes purines. 3. The ATP/ADP ratio ranged from 11 to 60 in the erythrocytes of the fish examined. 4. GTP is widely distributed in fish erythrocytes but its level ranged from 1 to 33 nmol/mg Hb (0.4 to 9 mumol/ml erythrocyte). 5. Lepomis and Esox exhibited a GTP/ATP ratio as elevated as in Anguilla; moreover the concentration of GTP per mol of Hb (physiologically most indicative) is higher in Lepomis, Esox, Ictalurus and Silurus than in Anguilla.

Animals↗