Have the Genetic Patterns of Fishes been Altered by Introductions or by Selective Fishing?

1957 ◽  
Vol 14 (6) ◽  
pp. 797-806 ◽  
Author(s):  
Richard B. Miller
Keyword(s):  
Introgressive Hybridization ◽  
Cutthroat Trout ◽  
Fish Populations ◽  
Gene Pools ◽  
Genetic Changes ◽  
Great Caution ◽  
Wide Range ◽  
Genetic Patterns ◽  
Genetic Pattern ◽  
Induced Changes

This paper is a review of some of the literature dealing with changes in freshwater fish populations following exploitation or after introduction of exotic species. The object of the review was to look for changes that could be attributed to alterations in the gene pools of the affected populations. Very little concrete evidence could be found, either because the investigations reviewed were not looking for genetic changes, or because such changes did not occur. Changes in some salmonids may be assigned to introgressive hybridization, particularly where rainbow and cutthroat trout have been put together on the Eastern Slopes. In many cases, however, exotics have apparently failed to contribute to the gene pool of the resident population, and most hybrids, when they occur, have been of low fertility.Fishes have a remarkable ability to respond to changes in population density by altered growth rates and times of maturity. These changed characters are not necessarily due to genetic changes and may be explained by assuming that fishes are pre-adapted to a wide range of conditions. There is a rather speculative suggestion that angling may select less intelligent fish, leading to an upgrading in intelligence of the fish. The general conclusion is that in the light of the existing evidence, great caution must be used in attributing to man-induced changes in fish populations changes in the genetic pattern.

scholarly journals Drivers of Infectious Disease Seasonality: Potential Implications for COVID-19

2021 ◽  
pp. 074873042098732
Author(s):  
N. Kronfeld-Schor ◽  
T. J. Stevenson ◽  
S. Nickbakhsh ◽  
E. S. Schernhammer ◽  
X. C. Dopico ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Infectious Diseases ◽  
Multidisciplinary Approach ◽  
Preliminary Assessment ◽  
Epidemiological Evidence ◽  
Wide Range ◽  
Human Coronaviruses ◽  
Induced Changes ◽  
And Behavior ◽  
Timing Phase

Not 1 year has passed since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19). Since its emergence, great uncertainty has surrounded the potential for COVID-19 to establish as a seasonally recurrent disease. Many infectious diseases, including endemic human coronaviruses, vary across the year. They show a wide range of seasonal waveforms, timing (phase), and amplitudes, which differ depending on the geographical region. Drivers of such patterns are predominantly studied from an epidemiological perspective with a focus on weather and behavior, but complementary insights emerge from physiological studies of seasonality in animals, including humans. Thus, we take a multidisciplinary approach to integrate knowledge from usually distinct fields. First, we review epidemiological evidence of environmental and behavioral drivers of infectious disease seasonality. Subsequently, we take a chronobiological perspective and discuss within-host changes that may affect susceptibility, morbidity, and mortality from infectious diseases. Based on photoperiodic, circannual, and comparative human data, we not only identify promising future avenues but also highlight the need for further studies in animal models. Our preliminary assessment is that host immune seasonality warrants evaluation alongside weather and human behavior as factors that may contribute to COVID-19 seasonality, and that the relative importance of these drivers requires further investigation. A major challenge to predicting seasonality of infectious diseases are rapid, human-induced changes in the hitherto predictable seasonality of our planet, whose influence we review in a final outlook section. We conclude that a proactive multidisciplinary approach is warranted to predict, mitigate, and prevent seasonal infectious diseases in our complex, changing human-earth system.

scholarly journals Morphometric and Molecular Analyses of Ostertagia leptospicularis Assadov, 1953 from Ruminants: Species Diversity or Host Influence?

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 182
Author(s):  
Anna Wyrobisz-Papiewska ◽  
Jerzy Kowal ◽  
Elżbieta Łopieńska-Biernat ◽  
Paweł Nosal ◽  
Iwona Polak ◽  
...  
Keyword(s):  
Host Species ◽  
Roe Deer ◽  
Bos Taurus ◽  
Capreolus Capreolus ◽  
Nematode Species ◽  
Molecular Techniques ◽  
Systematic Classification ◽  
Morphological Variations ◽  
Wide Range ◽  
Induced Changes

Ostertagia leptospicularis Assadov, 1953 was formally described in roe deer Capreolus capreolus and has been reported in a wide range of ruminants, including other Cervidae, as well as Bovidae. Nematode specimens derived from various host species exhibit morphological similarity; however, some differences can be observed. It is unclear if this is due to the differential reaction of one nematode species in different host species (i.e., host-induced changes) or because of distinct nematode species in these hosts (i.e., species complex). This paper focuses on specimens resembling O. leptospicularis f. leptospicularis and its closely related species (Ostertagia ostertagi f. ostertagi) collected from various hosts. Morphometric and molecular techniques were applied to assess host-induced changes in nematode morphology and to clarify its systematic classification. There was an overall effect of host species on measurements of nematodes resembling O. leptospicularis (both males and females), but the distinctiveness of the specimens from cattle Bos taurus were highlighted. The results obtained may suggest that the specimens of O. leptospicularis from cattle in Germany and cervids in central Europe belong to different strains. Furthermore, nematodes from the cervid strain appear to circulate within particular host species, which can be seen in the stated morphological variations.

Influence of Cotton Fiber Strength and Fineness on Fiber Damage during Lint Cleaning

1988 ◽  
Vol 58 (8) ◽  
pp. 433-438 ◽  
Author(s):  
J. K. Dever ◽  
J. R. Gannaway ◽  
R. V. Baker
Keyword(s):  
Significant Relationship ◽  
Cotton Fiber ◽  
Fiber Length ◽  
Fiber Strength ◽  
Fiber Breakage ◽  
Fiber Damage ◽  
Fiber Properties ◽  
Fiber Fineness ◽  
Wide Range ◽  
Induced Changes

Seven sources of cotton representing a wide range of fiber properties were roller ginned, saw ginned, or saw ginned plus processed through tandem saw lint cleaners or through an aggressive carding-type cleaner (Cottonmaster1). Lint cleaner induced changes in fiber length and nep count were compared to fiber property measurements from roller ginned samples. Fiber length deterioration from saw ginning was negatively correlated with fiber strength. Fiber breakage in lint cleaning was positively correlated with fiber fineness. Resistance to fiber length damage in ginning was explained best by fiber strength and fineness, or an estimate of individual fiber strength. Initial and final nep level were related to fineness, nonlint content, and upper quartile length, but an increase in neps due to lint cleaning had no significant relationship to fiber properties.

Abstract 196: Involvement of Peroxynitrite Formation in Angiotensin II Induced Changes in Na+K+ATPase Activity in HK2 Cells

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Arpan K Maiti ◽  
Mohammed T Islam ◽  
Ryosuke Satou ◽  
Dewan S Majid
Keyword(s):  
Angiotensin Ii ◽  
Colorimetric Assay ◽  
Renin Angiotensin System ◽  
Human Kidney ◽  
Protective Role ◽  
Renal Tubules ◽  
Proximal Tubule Cell ◽  
Wide Range ◽  
Induced Changes ◽  
Hk2 Cells

Angiotensin II (AngII) induces both superoxide (O 2 - ) and nitric oxide (NO) generation forming peroxynitrite (ONOO - ) in biological systems. To determine the role of ONOO - in AngII induced sodium excretory responses, we examined Na + K + ATPase (NKA) activity in cultured HK2 cells (human kidney proximal tubule cell line) incubated for 30 min with a wide range (10 pM to 200 μM) of AngII concentrations (conc) in the presence or absence of a ONOO - scavenger, mercapto-ethyl-guanadine (MEG; 200μM). Post incubation HK2 cellular membrane fractions were used for measurement of NKA activity via colorimetric assay capable of detecting inorganic phosphate (Pi). Baseline value of NKA activity in these HK2 cells was measured as 10.3 ±0.7 μmoles of Pi liberated/mg protein/hr (n=12). AngII exerts dose-dependent differential effects on NKA activity. Compared to the baseline value, NKA activity was increased at lower conc (13.7±1.3% at 10 pM to 19.6±1.5% at 100nM) and decreased at higher conc (-6.0±0.8% at 1 μM to -38±2.1% at 200 μM ) without any significant effect at 500 nM conc (-1.2±0.6%) of AngII. Interestingly, MEG treatment markedly attenuated these AngII induced changes in NKA activity, both at lower conc (activity increased only to 7.8±0.67% at 10 pM and to 8.9±0.57% at 100nM; an average reduction of 33.2±2.4% in stimulatory effects) and at higher conc (activity decreased to -3.0±0.7% at 1 μM and to -20±0.57% at 200 μM; an average reduction of 54.4±4.1% in inhibitory effects). Co-incubation with O 2 - scavenger, tempol (1 mM) or NO synthase inhibitor, nitro-L-arginine methyl ester (100 μM) did not alter these AngII induced responses in HK2 cells indicating that neither O 2 - , nor NO, was directly involved in mediating these responses. AT 1 receptor (AT 1 R) blocker, losartan (10μM) treatment prevented these AngII induced changes on NKA activity confirming the involvement of AT 1 R signaling in these responses. These findings demonstrate a direct contributory role for concomitant ONOO - generation in mediating AngII induced changes in NKA activity in the proximal tubular cells. These data also suggest a reno-protective role for ONOO - in minimizing sodium retaining action of AngII by the renal tubules, particularly in the conditions associated with enhanced renin-angiotensin system.

The interactive effects of stream temperature, stream size, and non-native species on Yellowstone cutthroat trout

2021 ◽  
Author(s):  
Robert Al-Chokhachy ◽  
Mike Lien ◽  
Bradley B. Shepard ◽  
Brett High
Keyword(s):  
Native Species ◽  
Cutthroat Trout ◽  
Population Level ◽  
Stream Temperature ◽  
Interactive Effects ◽  
Oncorhynchus Clarkii ◽  
Wide Range ◽  
Yellowstone Cutthroat Trout ◽  
Stream Size ◽  
Native Salmonids

Climate change and non-native species are considered two of the biggest threats to native salmonids in North America. We evaluated how non-native salmonids and stream temperature and discharge were associated with Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) distribution, abundance, and body size, to gain a more complete understanding of the existing threats to native populations. Allopatric Yellowstone cutthroat trout were distributed across a wide range of average August temperatures (3.2 to 17.7ºC), but occurrence significantly declined at colder temperatures (<10 ºC) with increasing numbers of non-natives. At warmer temperatures occurrence remained high, despite sympatry with non-natives. Yellowstone cutthroat trout relative abundance was significantly reduced with increasing abundance of non-natives, with the greatest impacts at colder temperatures. Body sizes of large Yellowstone cutthroat trout (90th percentile) significantly increased with warming temperatures and larger stream size, highlighting the importance of access to these more productive stream segments. Considering multiple population-level attributes demonstrates the complexities of how native salmonids (such as Yellowstone cutthroat trout) are likely to be affected by shifting climates.

Freshwater, Fish and the Future: Proceedings of the Global Cross-Sectoral Conference

2016 ◽  
Keyword(s):  
Fish Populations ◽  
Native Fish ◽  
Partnership Model ◽  
European Settlement ◽  
Southeastern Australia ◽  
Murray Darling Basin ◽  
Wide Range ◽  
Funding Opportunities ◽  
Funding Cuts

<em>Abstract</em> .—The Murray–Darling basin (MDB) in southeastern Australia, covers 1.1 million km<sup>2</sup>, involves six partner jurisdictions with a myriad of different government agencies, and, hence, provides an excellent example of the complexities of multijurisdictional management across a range of social and political tiers. In the MDB, fish and fisheries compete for water with agriculture, which is the traditional water user and is driven by national economics. Murray–Darling basin rivers are now highly regulated and generally in poor health, with native fish populations estimated to be at only about 10% of their pre-European settlement abundances. All native commercial fisheries are now closed, and the only harvest is by a recreational fishery. The six partner jurisdictions developed a Native Fish Strategy (NFS) to rehabilitate native fish populations to 60% of pre-European settlement levels after 50 years of implementation by addressing priority threats through a coordinated, long-term, whole-of-fish-community (all native fishes) approach. As there are a wide range of stakeholders, broad engagement was needed at a broad range of government and community levels. The NFS funding was discontinued after 10 years, not because of its lack of successes or project governance, but due to jurisdictional political changes and funding cuts that resulted in a failure of the collaborative funding structure. The withdrawal of considerable funding by one jurisdiction led to collective decline in monetary contributions and posed a threat to the multijurisdictional structures for both water and natural resource management (NRM) within the MDB. As a consequence, there was a review and reduction in NRM programs and a subsequent reduction in focus to the core business of water delivery. Reflection on the NFS, however, provides some useful insights as to the successes (many) and failures (funding) of this partnership model. Overall, the strategy and its structure was effective, as exhibited by an audit of outputs, outcomes, and networks; by the evident ongoing advocacy by NRM practitioners and the community; and by the continuation of ideas under other funding opportunities. This has provided a powerful legacy for future management of fishes in the MDB.

Cutthroat Trout: Evolutionary Biology and Taxonomy

2018 ◽  
Keyword(s):  
Great Basin ◽  
Late Miocene ◽  
Colorado River ◽  
Cutthroat Trout ◽  
Snake River Plain ◽  
Fish Populations ◽  
Snake River ◽  
Green River ◽  
Bear River ◽  
River Plain

<em>Abstract</em>.—In the past 17 million years (myr), the topography and drainage systems of the northwestern United States were drastically modified by the Yellowstone–Snake River Plain (YSRP) hotspot and associated east–west extension of the Basin and Range Province. These geologic changes influenced distribution and diversification of Cutthroat Trout <em>Oncorhynchus clarkii</em> and allowed connections between Snake River, Colorado River, and Great Basin fish populations beginning in the late Miocene. Studies of detrital zircon grains in Miocene to Holocene fluvial sands of the Snake River document the eastward migration of the regional drainage divide from central Idaho to northwestern Wyoming. This migration was concomitant with the southwest migration of the North American tectonic plate over the YSRP hotspot. In the late Miocene and Pliocene, since 10 million years before present (Ma), the Chalk Hills and Glenns Ferry lake systems formed on the western Snake River Plain and were hosts to diverse fish fauna. The modern Snake River formed after 3 Ma with the cutting of Hells Canyon and integration of the Snake and Columbia River drainage. In the Great Basin south of the Snake River watershed, Lake Lahontan has a history that goes back to the Miocene. Connections between the western Snake River Plain and the Great Basin were recurrent over the past 10 myr. In southeastern Idaho, the Bear River has had a complex drainage interaction with the Snake River and Bonneville watersheds. Lake Bonneville, in northern Utah, grew during Pleistocene glacial climate regimes. The modern Bear River connection to Lake Bonneville was initiated about 50,000 years before the present. The integration of the Green River with the Colorado River occurred in the late Miocene, developing after breaking of Eocene connections between the Green River and streams draining to the Atlantic Ocean. In sum, geological constraints are compatible with patterns of fish fossils and genetic linkages and identify mechanisms of colonization and isolation of fish populations that have resulted in regional diversification of Cutthroat Trout.

Diet selection in broiler chickens with corticosterone-induced changes in body composition

1997 ◽  
Vol 20 ◽  
pp. 121-123
Author(s):  
A. Sahin ◽  
J. M. Forbes
Keyword(s):  
Body Composition ◽  
Broiler Chickens ◽  
Diet Selection ◽  
Protein Concentrate ◽  
Male And Female ◽  
Protein Deposition ◽  
Macronutrient Selection ◽  
Wide Range ◽  
Corticosterone Treatment ◽  
Induced Changes

Birds attempt to compensate for an E : P (energy: protein) imbalance by increasing their intake of protein or energy from selected foods and this is related to changes in the birds’ body composition caused by corticosterone treatment.Corticosterone injections increase fatness despite increasing nitrogen and energy excretion (Bartov, 1985). More recently corticosterone has been used to modulate macronutrient selection in rats (Devenport et al., 1991; Bligh et al., 1993; Tempel et al., 1993) and chickens (Covasa and Forbes, 1995). The intake of high protein concentrate was decreased by corticosterone treatment in young chickens but not in older chickens (Covasa and Forbes, 1995). The previous results suggest that more information on corticosterone’s effect on diet selection will be obtained by using foods which can offer a wide range of choices to compose a proper diet (Covasa and Forbes, 1995). Therefore, two experiments were conducted to detect changes in protein preference in relation to reduced protein deposition and enhanced fattening induced by corticosterone in male and female growing broiler chickens.

The Institute of Evolution Wild Cereal Gene Bank at the University of Haifa

2018 ◽  
Vol 65 (3-4) ◽  
pp. 129-146 ◽  
Author(s):  
Tamar Krugman ◽  
Eviatar Nevo ◽  
Alex Beharav ◽  
Hanan Sela ◽  
Tzion Fahima
Keyword(s):  
Agronomic Traits ◽  
Natural Populations ◽  
Ecological Factors ◽  
Triticum Dicoccoides ◽  
Grain Protein Content ◽  
Hordeum Spontaneum ◽  
Gene Bank ◽  
Gene Pools ◽  
Wide Range ◽  
The University

The Institute of Evolution Wild Cereal Gene Bank (ICGB) at the University of Haifa, Israel, harbors extensive collections of wild emmer wheat (WEW), Triticum dicoccoides, and wild barley (WB), Hordeum spontaneum, the primary progenitors of wheat and barley, respectively. The ICGB also includes minor collections of 10 species of Aegilops, wild oat (Avena barbata), and Brachypodium stacei and B. hybridum (previously distachyon). Here, we describe the WEW and WB collections, explain sampling strategies, and introduce related studies. Natural populations were sampled across Israel along aridity gradients, occurring from north to south and from west to east, and in local microsites with variable (or contrasting) ecological factors. The collection sites varied greatly in terms of climatic (rainfall, temperature and humidity), edaphic (soil types), and topography (altitude, slope) variables. Thus, the ICGB collections represent wild cereals adapted to a wide range of habitats and eco-geographical conditions. We have collected and preserved these unique gene pools since mid-70th, and further used them for theoretical and applied studies in population genetics, evolution, domestication, adaptation to local and regional habitats, and coping mechanisms for a plethora of biotic and abiotic stresses. Our studies revealed that WEW and WB populations from Israel harbor high adaptive genetic diversity that can serve as a reservoir of beneficial alleles to improve important agronomic traits such as disease resistance, drought tolerance and improved grain protein content. These mostly untapped genetic resources could contribute to increasing world food production for the constantly rising human population.

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