Effects of bacterial treatment at early stages of Atlantic cod (Gadus morhuaL.) on larval survival and development

Increased larval viability with increased spawner age (i.e., maternal effects) have been observed in Atlantic cod (Gadus morhua) and Pacific rockfish (Sebastes spp.) stocks. Analytical results from a Beverton–Holt recruitment model indicate density-independent maternal effects affected the relative stock productivity and fishing rate reference points. We simulated populations based on Pacific cod (Gadus macrocephalus) and Pacific ocean perch (Sebastes alutus) to explore how estimates of reference points Fmsy and Fcrash are affected by maternal effects and potential interactions with life-history pattern, recruitment autocorrelation, and exploitation rate. Estimates of Fmsy and Fcrash were made from populations with maternal effects using either total larvae (proportional to eggs) or viable larvae (incorporating the maternal effect). Maternal effects have the largest impact upon estimated population productivity at high fishing rates. Estimates of Fmsy and Fcrash for cod were also affected by autocorrelated recruitment variability because of their reduced longevity compared with Pacific ocean perch. These results suggest the importance of evaluating the influence of maternal effects on estimated stock productivity on a case-by-case basis, particularly for depleted stocks composed of relatively young spawners.

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Influence of Bacteria on Larval Survival and Development in Rhagoletis (Diptera: Tephritidae)

Annals of the Entomological Society of America ◽

10.1093/aesa/82.5.633 ◽

1989 ◽

Vol 82 (5) ◽

pp. 633-640 ◽

Cited By ~ 9

Author(s):

Daniel J. Howard ◽

Guy L. Bush

Keyword(s):

Larval Survival ◽

Survival And Development

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Effects of Temperature and Humidity on the Rust-Red Flour Beetle, Tribolium-Castaneum (Herbst) (Coleoptera, Tenebrionidae), in Wheat-Grain

Australian Journal of Zoology ◽

10.1071/zo9870043 ◽

1987 ◽

Vol 35 (1) ◽

pp. 43 ◽

Cited By ~ 22

Author(s):

GG White

Keyword(s):

Tribolium Castaneum ◽

Larval Survival ◽

Population Increase ◽

Effect Of Temperature ◽

Wheat Grain ◽

Mathematical Functions ◽

Temperature And Humidity ◽

Survival And Development ◽

Effects Of Temperature ◽

Coleoptera Tenebrionidae

Rates of survival and development of the immature stages of Tribolium castaneum (Herbst) (Coleoptera : Tenebrionidae) were determined in wheat grain at constant temperatures from 20 to 37.5�C and constant relative humidities from 25 to 65%. The rates for eggs and pupae were similar to those previously published for T. castaneum in flour, but larval development was slower and mortality greater, except at low temperature and high humidity. The effect of temperature and humidity on rates of fertility and oviposition in young adults were also determined in wheat grain. The patterns of effects of temperature and humidity on oviposition were similar to those previously published for T. castaneum in flour, but the maximum observed oviposition rate was lower. Fertility was significantly reduced when densities of adults were greater than one pair per 250 g. Mathematical functions were fitted to data from the present and previous studies on age-specific survival and fecundity of adults; population growth rate statistics were calculated from life-table parameters defined by these functions. Under optimal conditions within the range of the present study (35�C, 65% RH), the innate capacity for increase rm was 0.84 per week. The limits for population increase, where rm is zero, were largely determined by.the limits for larval survival, which were approximately 35% RH, and 20-22�C at the lower limit and 40�C at the upper limit.

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Effect of twelve species of marine phytoplankton on larval survival and development of the mosquito Culex quinquefasciatus

International Journal of Marine Science ◽

10.5376/ijms.2015.05.0057 ◽

2015 ◽

Author(s):

V. Rai. Sushanth

Keyword(s):

Culex Quinquefasciatus ◽

Larval Survival ◽

Marine Phytoplankton ◽

Survival And Development

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Characterizations of Larval Gut Bacteria of Anopheles Subpictus Grassi and Their Role in Mosquito Development in Hooghly, West Bengal, India.

10.21203/rs.3.rs-707008/v1 ◽

2021 ◽

Author(s):

Madhurima Seal ◽

Soumendranath Chatterjee

Keyword(s):

Bacterial Flora ◽

Bacterial Load ◽

Larval Survival ◽

Gut Bacteria ◽

Bacterial Isolates ◽

Anopheles Subpictus ◽

Survival And Development ◽

Different Seasons ◽

Culture Suspension ◽

Developmental Characteristics

Abstract Malaria is a serious vector borne disease transmitted by different species of Anopheles mosquitoes. The present study was aimed to isolate & characterize the bacterial flora from the gut of An. subpictus larvae prevalent in Hooghly and explore their roles in host survival and development. Mosquito larvae and adults were collected from field and were maintained in laboratory. Bacterial load in the larval midgut was determined, predominant strains were isolated and characterized by polyphasic approach. Role of these bacteria in larval survival & development were assayed. Bacterial load in the gut of larvae was found to vary in field collected and lab reared mosquitoes in different seasons. Morphological, bio-chemical and molecular analysis explored four common bacterial isolates namely Bacillus subtilis, Bacillus pumilus, Bacillus cereus & Proteus vulgaris in the larval gut throughout the year. Larval survival rate was greatly reduced (0.06) & time of pupation was prolonged (17.8±0.57) in absence of their gut bacteria. Total tissue protein (7.78±0.56), lipid (2.25±0.19) & carbohydrate (16.5±0.79) contents of larvae and body weight & wing length of adult male (0.17±0.02 & 1.74±0.43) & female (0.19±0.02 & 1.99±0.46) mosquitoes were also found to be greatly reduced in the absence of gut bacteria. Developmental characteristics were restored with the introduction of culture suspension of all four resident gut bacterial isolates. Present study indicates that the mosquitoes solely depend on their gut bacteria for their survival & development. So, manipulation or control of this gut bacterial communities might inhibit survival & development of vector mosquitoes.

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Developmental plasticity among strains of the yellow mealworm, Tenebrio molitor L., under dry conditions

Journal of Insects as Food and Feed ◽

10.3920/jiff2021.0087 ◽

2021 ◽

pp. 1-8

Author(s):

C. Adamaki-Sotiraki ◽

C.I. Rumbos ◽

C.G. Athanassiou

Keyword(s):

Growth Performance ◽

Developmental Plasticity ◽

Survival Rates ◽

Tenebrio Molitor ◽

Larval Survival ◽

Survival And Development ◽

Dry Conditions ◽

Feed Utilisation ◽

Good Productivity ◽

Utilisation Efficiency

Edible insect production relies, among others, on the use of high-quality strains with good productivity characteristics. However, studies on the evaluation of the growth performance of different insect strains are limited. In this framework, the objective of the present study was to evaluate the growth and development under dry conditions of larvae of six Tenebrio molitor strains of different geographical origins, i.e. Greece, Italy, Turkey, Spain and USA, in terms of larval survival and development, as well as feed utilisation efficiency. In light of our results, we report the variable growth performance of different T. molitor strains in the absence of a moisture source. Although no significant differences were shown among the strains tested with regard to the final larval weights and survival rates, there were significant differences in the development time and the growth rate, which may affect the overall efficiency of T. molitor larvae production. Our study aims to highlight the significance of strain for the growth performance and consequently the productivity of T. molitor.

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