Life History and Smolt-to-Adult Survival of Keogh River Steelhead Trout (Salmo gairdneri) and the Relationship to Smolt Size

1988 ◽  
Vol 45 (7) ◽  
pp. 1110-1122 ◽  
Author(s):  
B. R. Ward ◽  
P. A. Slaney
Keyword(s):  
Age Structure ◽  
Predictive Models ◽  
Adult Survival ◽  
Salmo Gairdneri ◽  
Adult Size ◽  
Steelhead Trout ◽  
Adult Age ◽  
Large Fluctuations ◽  
The Relationship ◽  
Size Estimates

A decade of data on wild steelhead trout (Salmo gairdneri) from a coastal stream in British Columbia demonstrated large fluctuations in smolt number, age structure, size, estimates of adult run sizes, smolt-to-adult survival, and adult age. Adult runs averaged 922 (range 209–2730) with approximately 10% repeat spawning incidence. Females repeat spawned more than males and were more abundant as kelts, but maiden run adults were equally male and female. The proportion of males returning after 1, 2, and 3 yr in the ocean averaged 3, 62, and 35%, respectively; 58 and 42% of females returned after 2 and 3 yr, respectively. Adult age structure, smolt number, and smolt size varied biennially. Adult size decreased with freshwater age, but increased with ocean age of returns. Males were larger at each ocean age. Mean number of smolts (50:50 sex ratio) was 5543 and varied fivefold. Mean smolt length was 173 mm and mean weight was 49 g. Smolts were 2–5 yr old, and freshwater age 3 was most prevalent (average 56%). Mean survival from smolt to adult was 16% (7% from 1978 cohorts to 26% from 1982 cohorts). Survival was positively correlated with smolt length and weight. However, 1982 cohorts had twice the survival of other cohorts, possibly related to El Niño. No clear relationship was found between return age and mean smolt size, but on average, freshwater age was inversely related to ocean age. The relationships suggest that predictive models may be developed over the longer term from this type of study.

Attachment and Field Dependence: Individual Differences in Information Processing

2004 ◽  
Vol 9 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Patrizia Vermigli ◽  
Alessandro Toni
Keyword(s):  
Information Processing ◽  
Individual Differences ◽  
Field Dependence ◽  
Attachment Styles ◽  
Close Relationships ◽  
Adult Age ◽  
Males And Females ◽  
Figure Test ◽  
The Relationship ◽  
Measure Field

The present research analyzes the relationship between attachment styles at an adult age and field dependence in order to identify possible individual differences in information processing. The “Experience in Close Relationships” test of Brennan et al. was administered to a sample of 380 individuals (160 males, 220 females), while a subsample of 122 subjects was given the Embedded Figure Test to measure field dependence. Confirming the starting hypothesis, the results have shown that individuals with different attachment styles have a different way of perceiving the figure against the background. Ambivalent and avoidant individuals lie at the two extremes of the same dimension while secure individuals occupy the central part. Significant differences also emerged between males and females.

Persistence of giants: population dynamics of the limpet Scutellastra laticostata on rocky shores in Western Australia

2020 ◽  
Vol 646 ◽  
pp. 79-92
Author(s):  
RE Scheibling ◽  
R Black
Keyword(s):  
Population Dynamics ◽  
Western Australia ◽  
Size Structure ◽  
Survival Rates ◽  
Maximum Size ◽  
High Rate ◽  
Adult Survival ◽  
Rocky Shores ◽  
Adult Size ◽  
Decadal Time Scale

Population dynamics and life history traits of the ‘giant’ limpet Scutellastra laticostata on intertidal limestone platforms at Rottnest Island, Western Australia, were recorded by interannual (January/February) monitoring of limpet density and size structure, and relocation of marked individuals, at 3 locations over periods of 13-16 yr between 1993 and 2020. Limpet densities ranged from 4 to 9 ind. m-2 on wave-swept seaward margins of platforms at 2 locations and on a rocky notch at the landward margin of the platform at a third. Juvenile recruits (25-55 mm shell length) were present each year, usually at low densities (<1 m-2), but localized pulses of recruitment occurred in some years. Annual survival rates of marked limpets varied among sites and cohorts, ranging from 0.42 yr-1 at the notch to 0.79 and 0.87 yr-1 on the platforms. A mass mortality of limpets on the platforms occurred in 2003, likely mediated by thermal stress during daytime low tides, coincident with high air temperatures and calm seas. Juveniles grew rapidly to adult size within 2 yr. Asymptotic size (L∞, von Bertalanffy growth model) ranged from 89 to 97 mm, and maximum size from 100 to 113 mm, on platforms. Growth rate and maximum size were lower on the notch. Our empirical observations and simulation models suggest that these populations are relatively stable on a decadal time scale. The frequency and magnitude of recruitment pulses and high rate of adult survival provide considerable inertia, enabling persistence of these populations in the face of sporadic climatic extremes.

The regulation of day–night changes in hydroxyindole-O-methyltransferase activity in the pineal gland of steelhead trout (Salmo gairdneri)

1976 ◽  
Vol 54 (9) ◽  
pp. 1530-1534 ◽  
Author(s):  
John R. Smith ◽  
Lavern J. Weber
Keyword(s):  
Pineal Gland ◽  
Sharp Increase ◽  
Pineal Region ◽  
Salmo Gairdneri ◽  
Steelhead Trout ◽  
Methyltransferase Activity ◽  
Surgical Exposure

Elevation in pineal hydroxyindole-O-methyltransferase (HIOMT; EC 2.1.1.4) activity in juvenile steelhead trout was associated with the dark portions of three different photoperiods with a sharp increase in pineal HIOMT activity occurring in the first 4 h of darkness. This pattern of activity could be abolished by bilateral enucleation but not by surgical capping of the pineal region. Surgical exposure of the pineal region in blinded fish did not restore HIOMT responses to changes in lighting.

CNTF genotype is associated with muscular strength and quality in humans across the adult age span

2001 ◽  
Vol 90 (4) ◽  
pp. 1205-1210 ◽  
Author(s):  
Stephen M. Roth ◽  
Matthew A. Schrager ◽  
Robert E. Ferrell ◽  
Steven E. Riechman ◽  
E. Jeffrey Metter ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Body Mass ◽  
Muscular Strength ◽  
Peak Torque ◽  
Fat Free Mass ◽  
Muscle Quality ◽  
Knee Extensors ◽  
Muscular Power ◽  
Adult Age ◽  
The Relationship

The relationship between ciliary neurotrophic factor (CNTF) genotype and muscle strength was examined in 494 healthy men and women across the entire adult age span (20–90 yr). Concentric (Con) and eccentric (Ecc) peak torque were assessed using a Kin-Com isokinetic dynamometer for the knee extensors (KE) and knee flexors (KF) at slow (0.52 rad/s) and faster (3.14 rad/s) velocities. The results were covaried for age, gender, and body mass or fat-free mass (FFM). Individuals heterozygous for the CNTF null (A allele) mutation (G/A) exhibited significantly higher Con peak torque of the KE and KF at 3.14 rad/s than G/G homozygotes when age, gender, and body mass were covaried ( P < 0.05). When the dominant leg FFM (estimated muscle mass) was used in place of body mass as a covariate, Con peak torque of the KE at 3.14 rad/s was also significantly greater in the G/A individuals ( P < 0.05). In addition, muscle quality of the KE (peak torque at 3.14 rad · s−1 · leg muscle mass−1) was significantly greater in the G/A heterozygotes ( P < 0.05). Similar results were seen in a subanalysis of subjects 60 yr and older, as well as in Caucasian subjects. In contrast, A/A homozygotes demonstrated significantly lower Ecc peak torque at 0.52 rad/s for both KE and KF compared with G/G and G/A groups ( P < 0.05). No significant relationships were observed at 0.52 rad/s between genotype and Con peak torque. These data indicate that individuals exhibiting the G/A genotype possess significantly greater muscular strength and muscle quality at relatively fast contraction speeds than do G/G individuals. Because of high positive correlations between fast-velocity peak torque and muscular power, these findings suggest that further investigations should address the relationship between CNTF genotype and muscular power.

scholarly journals Significance of SCIWORA in adults

2015 ◽  
Vol 14 (2) ◽  
pp. 134-137
Author(s):  
Pedro Luis Bazán
Keyword(s):  
Japanese Orthopaedic Association ◽  
Prospective Evaluation ◽  
Resonance Imaging ◽  
Adult Age ◽  
Intramedullary Lesion ◽  
Central Cord Syndrome ◽  
Asia Score ◽  
The Relationship ◽  
Cervical Arthrosis

<sec><title>OBJECTIVE:</title><p> Recognizing the importance of SCIWORA in adult age; analyze the usefulness of complementary studies; evaluating therapeutic options; learn about the evolution of the treated patients.</p></sec><sec><title>METHODS:</title><p> A prospective evaluation with a minimum follow-up of 5 years, eight elderly patients with cervical arthrosis and diagnosis of SCIWORA. The Japanese Orthopaedic Association (JOA) scale and ASIA were used on admission and at 6, 12, 24, 36, 48 and 60 months.</p></sec><sec><title>RESULTS:</title><p> The central cord syndrome (CCS) was the neurological condition at admission. One patient recovered after corticosteroid therapy, but later, his disability worsened, and he was operated at 18 months, another patient recovered and a third died. The other patients underwent laminoplasty in the first 72 hours; patients with partial severity condition had a minimum improvement of five points in JAO scale and those with severe conditions died.</p></sec><sec><title>CONCLUSIONS:</title><p> The low-energy trauma can decompensate the relationship between container and content in the spine with asymptomatic arthrosis, and can be devastating to the patient. The diagnosis of intramedullary lesion is made by magnetic resonance imaging. Patients with incomplete deficit undergoing laminoplasty reached at least one level in ASIA score. The potential postoperative complications can be serious.</p></sec>

Movements of Rainbow Steelhead Trout (Salmo Gairdneri) in Lake Ontario and a Hypothesis for the Influence of Spring Thermal Structure

1986 ◽  
Vol 12 (4) ◽  
pp. 304-313 ◽  
Author(s):  
James M. Haynes ◽  
David C. Nettles ◽  
Kevin M. Parnell ◽  
Michael P. Voiland ◽  
Robert A. Olson ◽  
...  
Keyword(s):  
Thermal Structure ◽  
Lake Ontario ◽  
Salmo Gairdneri ◽  
Steelhead Trout

Differential fertility among immigrants to England and Wales and some implications for population projections

1969 ◽  
Vol 1 (S1) ◽  
pp. 119-127 ◽  
Author(s):  
Jean Thompson
Keyword(s):  
Age Structure ◽  
Age Groups ◽  
Population Projections ◽  
Fertility Rates ◽  
Female Population ◽  
Differential Fertility ◽  
England And Wales ◽  
Adult Age ◽  
Completed Family Size ◽  
Socio Economic Factors

SummaryThe age structure of the immigrant female population as shown by the 1961 Census was heavily biased towards the young adult age groups, where fertility rates are highest. The birth rate for such a population could be expected considerably to exceed the average for this country as a whole, due to differences in age structure alone. The Census also showed marked differences betwen the fertility rates of different groups of immigrants but suggested that for the most important groups —from the Irish Republic, the Indian sub-continent and the Caribbean—they then amounted to a completed family size of roughly ½ child above the England and Wales average. There were also marked differences in 1961 between the socio-economic structure of immigrant groups; such evidence as there is points to socio-economic factors as playing an important part in explaining the fertility of immigrants, and its possible change over time.

scholarly journals A New Analysis of Ammonia and Sodium Transport Through the Gills of the Freshwater Rainbow Trout (Salmo Gairdneri)

1989 ◽  
Vol 142 (1) ◽  
pp. 155-175 ◽  
Author(s):  
MARTINE AVELLA ◽  
MICHEL BORNANCIN
Keyword(s):  
Sodium Transport ◽  
Proton Transport ◽  
External Medium ◽  
Ammonia Excretion ◽  
Gill Tissue ◽  
Ammonia Concentration ◽  
Salmo Gairdneri ◽  
Sodium Absorption ◽  
Ammonia Transport ◽  
The Relationship

The mechanism of ammonia excretion and sodium absorption was re-examined in trout using the isolated-perfused head preparation. Preliminary experiments in which ammonia concentration was increased on the blood side (internal) showed that ammonia and sodium transport was uncoupled. For ammonia excretion, our results showed that gill tissue endogenously produces ammonia. A correlation was demonstrated between ammonia excretion and the internal-external ammonia gradient. We conclude that diffusion in the form of NH3 was responsible for ammonia efflux and we were therefore able to estimate its diffusion coefficient (DNH3 = 1.55×10−6cm2s−1) and permeability coefficient (6×10−3cm s−1). This ammonia diffusion was shown to be modified according to the external proton availability. For sodium absorption, significant changes were caused by indirect modifications of intracellular pH brought about by addition of acetazolamide inside or ammonia outside or by acidification of the internal or external medium. The relationship between sodium and proton transport was further confirmed by the action of the drug amiloride and the measurement of H+ excretion. A possible model representing sodium, proton and ammonia transport through the gill epithelium is proposed.

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