A synthesis of senescence predictions for indeterminate growth, and support from multiple tests in wild lake trout

Senescence—the deterioration of functionality with age—varies widely across taxa in pattern and rate. Insights into why and how this variation occurs are hindered by the predominance of laboratory-focused research on short-lived model species with determinate growth. We synthesize evolutionary theories of senescence, highlight key information gaps and clarify predictions for species with low mortality and variable degrees of indeterminate growth. Lake trout are an ideal species to evaluate predictions in the wild. We monitored individual males from two populations (1976–2017) longitudinally for changes in adult mortality (actuarial senescence) and body condition (proxy for energy balance). A cross-sectional approach (2017) compared young (ages 4–10 years) and old (18–37 years) adults for (i) phenotypic performance in body condition, and semen quality—which is related to fertility under sperm competition (reproductive senescence)—and (ii) relative telomere length (potential proxy for cellular senescence). Adult growth in these particular populations is constrained by a simplified foodweb, and our data support predictions of negligible senescence when maximum size is only slightly larger than maturation size. Negative senescence (aka reverse senescence) may occur in other lake trout populations where diet shifts allow maximum sizes to greatly exceed maturation size.

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A synthesis of senescence predictions for indeterminate growth, and support from multiple tests in wild lake trout

10.1101/2021.10.05.463025 ◽

2021 ◽

Author(s):

Craig F Purchase ◽

Anna C Rooke ◽

Michael J Gaudry ◽

Jason R Treberg ◽

Elizabeth A Mittell ◽

...

Keyword(s):

Body Condition ◽

Lake Trout ◽

Semen Quality ◽

Maximum Size ◽

Adult Mortality ◽

Cross Sectional ◽

Indeterminate Growth ◽

Adult Growth ◽

In The Wild ◽

Negligible Senescence

Senescence, or the deterioration of functionality with age, varies widely across taxa in pattern and rate. Insights into why and how this variation occurs are hindered by the predominance of lab-focused research on short-lived model species with determinate growth. We synthesize evolutionary theories of senescence, highlight key information gaps, and clarify predictions for species with low mortality and variable degrees of indeterminate growth. Lake trout are an ideal species to evaluate predictions in the wild. We monitored individual males from two populations (1976-2017) longitudinally for changes in adult mortality (actuarial senescence) and body condition (proxy for energy balance). A cross-sectional approach (2017) compared young (ages 4-10 years) and old (18-37 years) adults for (1) phenotypic performance in body condition, and semen quality - which is related to fertility under sperm competition (reproductive senescence), and (2) relative telomere length (potential proxy for cellular senescence). Adult growth in these particular populations is constrained by a simplified food web, and our data support predictions of negligible senescence when maximum size is only slightly larger than maturation size. Negative senescence (aka reverse senescence) may occur in other lake trout populations where diet shifts allow maximum sizes to be much larger than maturation size.

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No long-term effect of intracoelomic acoustic transmitter implantation on survival, growth, and body condition of a long-lived stenotherm in the wild

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2020-0106 ◽

2020 ◽

Author(s):

Justin A. G. Hubbard ◽

Brendan E. Hickie ◽

Jeff Bowman ◽

Lee E. Hrenchuk ◽

Paul J. Blanchfield ◽

...

Keyword(s):

Body Condition ◽

Lake Trout ◽

Negative Effects ◽

Term Survival ◽

Acoustic Transmitter ◽

Negative Effect ◽

In The Wild ◽

Surgical Implantation ◽

Fish Survival

A fundamental assumption of biotelemetry studies is that there are no adverse consequences from the surgical implantation or presence of the acoustic transmitter. In fisheries, most studies have evaluated this assumption over only short time periods (<2 y) in a laboratory setting. Here we compared the survival, growth, and body condition of populations of Lake Trout (Salvelinus namaycush) in three lakes containing tagged and untagged individuals over a 12-year period (2002-2013). We found no significant negative effects of acoustic telemetry tagging on the long-term survival of fish (estimates of combined annual survival ranged from 67% to 91%), and no negative effect of surgical implantation on growth or body condition for fish of either sex. Additionally, we found no significant effect of transmitter:fish mass ratio on fish survival, growth (with the exception of smaller-bodied fish in one lake), or condition. All implanted fish received tags weighing <1.25% of their mass (in water), indicating that this criterion is desirable for larger-bodied adult Lake Trout. Our findings support the assumption that long-lived fish species tagged with acoustic transmitters via intracoelomic surgery survive, grow, and maintain body condition similar to un-tagged conspecifics over the long-term in the wild.

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Association between blood metal concentrations and human semen quality: a cross-sectional study in Hong Kong

10.26226/morressier.5af300ad738ab10027aa92c2 ◽

2018 ◽

Author(s):

Xiao Shi ◽

David YL Chan

Keyword(s):

Hong Kong ◽

Semen Quality ◽

Cross Sectional Study ◽

Human Semen ◽

Sectional Study ◽

Cross Sectional ◽

Metal Concentrations

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Optimizing the Properties of La0.8Sr0.2CrO3 Thin Films through Post-Annealing for High-Temperature Sensing

Nanomaterials ◽

10.3390/nano11071802 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1802

Author(s):

Dan Liu ◽

Peng Shi ◽

Yantao Liu ◽

Yijun Zhang ◽

Bian Tian ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Annealing Temperature ◽

Rf Sputtering ◽

Maximum Size ◽

Cross Sectional ◽

Post Annealing ◽

Maximum Conductivity ◽

Different Temperatures ◽

Post Annealing Temperature

La0.8Sr0.2CrO3 (0.2LSCO) thin films were prepared via the RF sputtering method to fabricate thin-film thermocouples (TFTCs), and post-annealing processes were employed to optimize their properties to sense high temperatures. The XRD patterns of the 0.2LSCO thin films showed a pure phase, and their crystallinities increased with the post-annealing temperature from 800 °C to 1000 °C, while some impurity phases of Cr2O3 and SrCr2O7 were observed above 1000 °C. The surface images indicated that the grain size increased first and then decreased, and the maximum size was 0.71 μm at 1100 °C. The cross-sectional images showed that the thickness of the 0.2LSCO thin films decreased significantly above 1000 °C, which was mainly due to the evaporation of Sr2+ and Cr3+. At the same time, the maximum conductivity was achieved for the film annealed at 1000 °C, which was 6.25 × 10−2 S/cm. When the thin films post-annealed at different temperatures were coupled with Pt reference electrodes to form TFTCs, the trend of output voltage to first increase and then decrease was observed, and the maximum average Seebeck coefficient of 167.8 µV/°C was obtained for the 0.2LSCO thin film post-annealed at 1100 °C. Through post-annealing optimization, the best post-annealing temperature was 1000 °C, which made the 0.2LSCO thin film more stable to monitor the temperatures of turbine engines for a long period of time.

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Drinking Water Arsenic and Adverse Reproductive Outcomes in Men and Women: A Systematic PRISMA Review

Water ◽

10.3390/w13141885 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1885

Author(s):

Ida M. Barsøe ◽

Ninna H. Ebdrup ◽

Hannah S. Clausen ◽

Julie Lyngsø ◽

Jörg Schullehner ◽

...

Keyword(s):

Drinking Water ◽

Spontaneous Abortion ◽

Semen Quality ◽

Arsenic Exposure ◽

Quality Characteristics ◽

Reproductive Outcomes ◽

Case Control Studies ◽

Time To Pregnancy ◽

Cross Sectional ◽

Men And Women

Infertility is a worldwide health issue, but mechanisms of both male and female reproductive toxicity remain to be elucidated. So far, a limited focus has been on potentially harmful environmental factors such as arsenic, which is naturally occurring in groundwater. The objective of this review was to systematically investigate the association between arsenic in drinking water and adverse reproductive outcomes in men and women of fertile age. We conducted a systematic literature search and included case-control studies and cohort studies reporting on decreased semen quality characteristics, increased time to pregnancy, infertility, or spontaneous abortion. In total, 433 articles were screened and ultimately, eight studies were included. Included literature was quality assessed with the Newcastle-Ottawa Scale. Findings were reported in a narrative synthesis. Only one study investigated male fertility. An association between increasing arsenic exposure and decreasing semen quality characteristics was found, as well as an indication of arsenic accumulation in seminal plasma. These findings are, however, at high arsenic levels (>1000 µg/L). No consistent evidence was found to support the hypothesis that arsenic exposure from drinking water is a cause of longer waiting time to pregnancy or spontaneous abortion, being the only endpoints investigated in the included literature. In conclusion; the evidence is sparse and of varying quality, however, it does warrant attention, as it conflicts with existing evidence, mainly from cross-sectional or ecologic studies.

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Prevalence of Ovine Haemonchosis in Wukro, Ethiopia

Journal of Parasitology Research ◽

10.1155/2015/635703 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Lidya Gebresilassie ◽

Berihun Afera Tadele

Keyword(s):

Body Condition ◽

Haemonchus Contortus ◽

Significant Variation ◽

Cross Sectional Study ◽

Cross Sectional ◽

Highly Pathogenic ◽

Good Body Condition ◽

Associated Risk Factors ◽

Female Sheep ◽

Important Disease

Background.Haemonchosiscaused byHaemonchus contortusis a predominant, highly pathogenic, and economically important disease of sheep and goats.Objective. Assessing the prevalence ofHaemonchusparasite and its associated risk factors in sheep slaughtered at different restaurants of Wukro.Methods. Cross-sectional study using random sampling from November 2013 to April 2014 in a total of 384 sheep was conducted and SPSS version 20 software using descriptive statistics was used for data analysis andP<0.05was considered significant.Result. The overall prevalence ofHaemonchus contortuswas 40.9% (n=157). The prevalence in medium body condition 27.3% (n=105) varies significantly from that of good body condition 13.5% (n=52) (P<0.05). Moreover, there was significant variation (P<0.05) in the prevalence in young and adult sheep with rates of 21.9% (n=84) and 19% (n=73), respectively. At the same time, there is significant variation (P<0.05) in male and female sheep with prevalence of 29.7% (n=114) and 11.2% (n=43), respectively. The prevalence of 25.3% (n=97) in sheep that originated from Negash compared to Wukro and Agulae showed no significant variation (P>0.05).Conclusion. The current finding revealed that significant numbers of sheep were affected by the parasites. Hence strategic deworming with good husbandry practice should be implemented.

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Lack of relationship between simulated fish population responses and their life history traits: inadequate models, incorrect analysis, or site-specific factors?

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f05-049 ◽

2005 ◽

Vol 62 (4) ◽

pp. 886-902 ◽

Cited By ~ 18

Author(s):

Kenneth A Rose

Keyword(s):

Life History ◽

Life History Traits ◽

Lake Trout ◽

Fish Population ◽

Population Models ◽

Site Specific ◽

Density Dependent ◽

Population Responses ◽

Adult Growth ◽

Specific Factors

Relationships between fish population responses to changes in their vital rates and commonly available life history traits would be a powerful screening tool to guide management about species vulnerability, to focus future data collection on species and life stages of concern, and to aid in designing effective habitat enhancements. As an extension of previous analyses by others, I analyzed the responses to changes in fecundity and yearling survival of age-structured matrix and individual-based population models of 17 populations comprising 10 species. Simulations of the matrix models showed that the magnitude of population responses, but not the relative order of species sensitivity, depended on the state (sustainable or undergoing excessive removals) of the population. Matrix and individual-based models predicted population responses that appeared to be unrelated to their species-level life history traits when responses were plotted on a three-end-point life history surface. Density-dependent adult growth was added to the lake trout (Salvelinus namaycush) matrix model, and simulations demonstrated the potential importance to predicted responses of density-dependent processes outside the usual spawnerrecruit relationship. Four reasons for the lack of relationship between population responses and life history traits related to inadequate population models, incorrect analysis, inappropriate life history model, and important site-specific factors are discussed.

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Assisted colonisation trial of the eastern barred bandicoot (Perameles gunnii) to a fox-free island

Wildlife Research ◽

10.1071/wr16198 ◽

2017 ◽

Vol 44 (7) ◽

pp. 484 ◽

Cited By ~ 6

Author(s):

Rebecca Groenewegen ◽

Dan Harley ◽

Richard Hill ◽

Graeme Coulson

Keyword(s):

Habitat Use ◽

Body Condition ◽

Red Fox ◽

Suitable Habitat ◽

Viable Option ◽

Predator Exclusion ◽

In The Wild ◽

Radio Transmitters ◽

Release Group ◽

Small Sites

Context Assisted colonisation has the potential to protect species from intractable threats within their historical ranges. The Australian mainland subspecies of the eastern barred bandicoot (Perameles gunnii) is extinct in the wild, with surviving populations restricted to small sites protected by predator–barrier fences. PVA modelling shows that a self-sustaining bandicoot population would require an area free of the introduced red fox (Vulpes vulpes) of at least 2500ha. French Island is outside the historic range of the species, but is fox-free and contains around 9000ha of potentially suitable habitat. Aims This study will assess the suitability of French Island as a potential site for a self-sustaining eastern barred bandicoot population by conducting a 1-year assisted colonisation trial to assess habitat use, body condition and survival. Methods Between July and September 2012, 18 adult bandicoots were released. We radio-tracked bandicoots using intraperitoneal radio-transmitters for up to 122 days and trapped fortnightly. Key results The release group met the three measures of success: (1) appropriate habitat use; (2) recovery of post-release bodyweight; and (3) founder survival exceeding 100 days. Habitat use and body condition throughout the trial reflected that of mainland populations, and seven bandicoots survived longer than 100 days. Mortality was greatest in the first month, with veterinary investigations confirming two deaths due to cat predation, two deaths from toxoplasmosis and one unknown cause of death. Bandicoots that survived longer than 100 days occupied higher, drier ground than those that did not. Toxoplasmosis cases were associated with lower topographic position on the site. Conclusions Our results suggest that French Island provides suitable habitat for the establishment of a population of eastern barred bandicoots. On French Island, toxoplasmosis was identified as an important source of mortality in addition to cat predation, and warrants further investigation. Implications Given the costs and challenges of predator control and the maintenance of predator exclusion fences, assisted colonisation to one or more fox-free islands remains the most viable option to establish self-sustaining bandicoot populations. Our results highlight the value in conducting trial releases ahead of major translocations.

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