Influence of temperature on larval development of four co-occurring species of the brachyuran genus Cancer

1994 ◽  
Vol 118 (4) ◽  
pp. 593-600 ◽  
Author(s):  
S. D. Sulkin ◽  
G. McKeen
Author(s):  
Monika Weiss ◽  
Sven Thatje ◽  
Olaf Heilmayer ◽  
Klaus Anger ◽  
Thomas Brey ◽  
...  

The influence of temperature on larval survival and development was studied in the edible crab, Cancer pagurus, from a population off the island of Helgoland, North Sea. In rearing experiments conducted at six different temperatures (6°, 10°, 14°, 15°, 18° and 24°C), zoeal development was only completed at 14° and 15°C. Instar duration of the Zoea I was negatively correlated with temperature. A model relating larval body mass to temperature and developmental time suggests that successful larval development is possible within a narrow temperature range (14° ± 3°C) only. This temperature optimum coincides with the highest citrate synthase activity found at 14°C. A comparison for intraspecific variability among freshly hatched zoeae from different females (CW 13–17 cm, N = 8) revealed that both body mass and elemental composition varied significantly. Initial larval dry weight ranged from 12.1 to 17.9 μg/individual, the carbon content from 4.6 to 5.8 μg/individual, nitrogen from 1.1 to 1.3 μg/individual, and the C:N ratio from 4.1 to 4.4. A narrow larval temperature tolerance range of C. pagurus as well as the indication of intraspecific variability in female energy allocation into eggs may indicate a potential vulnerability of this species to climate change. Large-scale studies on the ecological and physiological resilience potential of this commercially fished predator are needed.


Parasitology ◽  
1964 ◽  
Vol 54 (1) ◽  
pp. 59-65 ◽  
Author(s):  
J. A. Dinnik ◽  
N. N. Diknik

Experiments on the larval development of Fasciola gigantica carried out under natural conditions have shown that at temperatures of 16° C. or less the rediae did not produce cercariae. The first-generation rediae, developed from the sporocyst, and all the rediae of subsequent generations produced only daughter rediae and did not change over to the production of cercariae as long as the low temperatures of the cold season lasted.As soon as the cold season ended and the temperature of the water in the aquaria containing the infected snails rose to a mean maximum of 20° C. all the rediae switched from redial to cercarial production.


1978 ◽  
Vol 110 (6) ◽  
pp. 623-626 ◽  
Author(s):  
W. P. Roberts ◽  
Jean R. Proctor ◽  
J. H. H. Phillips

AbstractLaboratory tests, at constant temperatures, were conducted to evaluate quantitatively the influence of temperature on development of the Oriental fruit moth, Grapholitha molesta (Busck). The results showed that at the highest temperature (30°C) some larvae had four instars and some had five, indicating a mixed population. Fifth instar larvae developed only at the highest temperature (30°C) where larval development was also most rapid. It can, therefore, be assumed that the Oriental fruit moth has four distinct larval instars when reared in the laboratory at 15°–24 °C.


Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 960
Author(s):  
Simone Morelli ◽  
Mariasole Colombo ◽  
Anastasia Diakou ◽  
Donato Traversa ◽  
Marika Grillini ◽  
...  

The metastrongyloid Aelurostrongylus abstrusus has an indirect lifecycle involving gastropod intermediate hosts. The widespread snail Cornu aspersum is an efficient intermediate host of A. abstrusus. As the temperature may influence the developmental rate of metastrongyloids from first (L1) to the third infective larval stage (L3) inside molluscs, this study evaluated the effect of two controlled temperatures on the development of A. abstrusus in C. aspersum. Overall, 300 snails were infected with 500 L1 of A. abstrusus and kept at ∼25 °C. Fifteen days post infection (D15), the overall developmental rate to L3 (0.8%) was assessed in a subset of 20 snails. The remaining gastropods were divided in 2 groups, i.e., 180 still kept at ∼25 °C (G1) and 100 hibernated at ∼4 °C (G2). On D30, the larval development was evaluated in 20 snails from each group, while another batch of 80 snails was selected random from G1 and hibernated at ∼4 °C (G3). The larval developmental rate was determined digesting 20 snails from each of the three groups on D45, D60, and D75. The higher mean developmental rate was registered in G1 (3.8%) compared to G2 (1.9%) and G3 (2.3%), indicating that the development to L3 of A. abstrusus in C. aspersum is positively influenced by the increase of temperature.


Author(s):  
L. Valdes ◽  
M. T. Alvarez-Ossorio ◽  
E. Gonzalez-Gurriaran

The influence of temperature on the duration of the embryonic and larval development in Necora puber (L., 1767) was studied. Nine different temperatures were used for the eggs and seven for the larvae, in both cases ranging from 2 to 35°C. The temperature range where visible development was obtained was between 4 and 31°C, with the lowest lethal temperature (temperature at which the eggs did not show any sign of development and development did not resume when the eggs were placed at 15°C) being between 2 and 4°C and the highest lethal temperature between 31 and 35°C for both eggs and larvae.Temperature was found to be inversely related to developmental time. The incubation period (D) fluctuated between 76 days at 10°C and 17·6 days at 25°C, with an increase in the rate of development (100/D) from 1·13 to 5·55 between these two temperatures. The larval period varied between 48·5 days at 15°C and 28 days at 25°C with rates of development of 2·08 and 3·57 respectively. The adjustment equations used show that temperature has a greater accelerating effect on eggs than on larvae. A simple potential equation, D=aT, describes the relationship between temperature and developmental time better than the Belehrádek equation, D=a(T-t).Acording to the fitted equations developmental time from spawning to the first postlarval stage is completed in 91–105 days at temperatures of 13–15°C which is very close to our experimental data. The model proposed also fits most of the data from the available literature even those for other species such as Liocarcinus holsatus (Fabricius, 1798) and Carcinus maenas (L., 1758), which suggests that a similar response of developmental time vs temperature could be expected from other related Portunidae.


1967 ◽  
Vol 99 (3) ◽  
pp. 244-249 ◽  
Author(s):  
W. A. Smirnoff

AbstractThe effect of temperatures on the development of a virus disease of Neodiprion swainei Midd. was studied at constant temperatures of 30° and 12 °C., and under fluctuating temperatures (15°–20 °C.) in the laboratory and outdoors. Viral concentrations of 30 × 106 polyhedra per ml. and 1 × 106 polyhedra per ml. were used. Only the higher concentration of virus was effective at 30 °C. At 12 °C. the incubation period of the disease was prolonged and mortality caused by the virus was considerably reduced for both viral concentrations. Mortality due to the virus was similar at both viral concentrations for the fluctuating temperatures which were within the optimum temperature range for larval development.


1991 ◽  
Vol 69 (5) ◽  
pp. 1356-1365 ◽  
Author(s):  
John W. McCreadie ◽  
Murray H. Colbo

The influence of temperature on survival, development, and growth of simuliid larvae of the EFG/C cytotype and of a mixed population of ACD–AA cytotypes was examined, employing a stir bar rearing system. The EFG/C type completed larval development from 5 to 30 °C, with maximum survival between 15 and 20 °C (68.0–73.5%). The ACD–AA types completed development between 5 and 25 °C, with maximum survival between 15 and 25 °C (55.3–61.0%). The temperature–survivorship curve of EFG/C was significantly different from the ACD–AA one. Using regression analysis, threshold temperature was determined to be 0 °C. Mean degree-days required to complete larval development varied depending on temperature, cytotype, and sex. Degree-day determination in the laboratory agreed well with field data. Final larval instars of EFG/C and ACD were largest at 10–15 °C. The results are compared with those of previous studies and discussed in relation to "optimal temperature" and fitness. The size and band discrimination of the salivary gland polytene chromosomes used to identify the above cytotypes were found to vary with rearing conditions. We suggest that larvae reared at 15 °C and fed Tetra, at a dosage of ≥ 0.3 mg/larva per day, will provide good-quality chromosome preparations.


Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).


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