Effects of age, temperature, and previous infection on the development of Physaloptera maxillaris (Nematoda: Physalopteroidea) in field crickets (Acheta pennsylvanicus)

1976 ◽  
Vol 54 (4) ◽  
pp. 442-448 ◽  
Author(s):  
Richard J. Cawthorn ◽  
Roy C. Anderson
Keyword(s):  
Growth Rate ◽  
Field Crickets ◽  
Larval Length ◽  
Third Stage ◽  
Previous Infection ◽  
Final Length

Larvae of Physaloptera maxillaris developed to the stage infective to skunk in only 9 days in adult crickets held at 30 °C. The growth rate and final length of third-stage larvae of P. maxillaris were greater in adult crickets held at higher temperatures (i.e. 30 °C) than at lower temperatures (i.e. 20.25 °C).Crickets as young as 1 week of age were successfully infected with P. maxillaris. Third-stage larvae that were recovered from older nymphs tended to be shorter than larvae in younger nymphs. There was no correlation between mean larval length at 25 days after infection, and the total number of larvae per cricket in older nymphs. Adult and nymphal crickets were successfully given challenge infections.

Immunization of Guineapigs against Ascaris suum

1960 ◽  
Vol 34 (3-4) ◽  
pp. 347-348 ◽  
Author(s):  
L. F. Taffs
Keyword(s):  
Control Group ◽  
Group Iii ◽  
Successful Attempt ◽  
Group I ◽  
Third Stage ◽  
Previous Infection ◽  
Group Ii ◽  
Intravenous Inoculation ◽  
Subcutaneous Inoculation ◽  
Control Group Group

It has been shown that guineapigs can be effectively protected against re-infection by the subcutaneous inoculation of embryonated Ascaris eggs (Soulsby, 1957). The purpose of this communication is to report a successful attempt to immunize guineapigs against a lethal oral challenge dose of eggs by the intravenous inoculation of third stage larvae of A. suum.Three groups, each containing nine guineapigs, were infected with Ascaris as follows: Group I was given 10,000 eggs by mouth. Group II Was inoculated intravenously with 2,000 third stage Ascaris larvae which had been obtained from the lungs of other guineapigs on the sixth day of infection. Both groups were challenged at the same time with 250,000 eggs by mouth, along with a control group (Group III) which had no previous infection. The guineapigs in Group I were re-infected after 18 days and those in Group II after 12 days.

scholarly journals Effect of temperature on growth of the threatened annual fish Austrolebias nigrofasciatus Costa & Cheffe 2001

2012 ◽  
Vol 12 (4) ◽  
pp. 68-73 ◽  
Author(s):  
Matheus Vieira Volcan ◽  
Alinca Peres da Fonseca ◽  
Mário Roberto Chim Figueiredo ◽  
Luís André Sampaio ◽  
Ricardo Berteaux Robaldo
Keyword(s):  
Growth Rate ◽  
Sexual Dimorphism ◽  
Effect Of Temperature ◽  
Initial Growth ◽  
Southern Brazil ◽  
Annual Fish ◽  
Annual Killifish ◽  
In Captivity ◽  
Final Length

This study evaluated the effect of temperature on growth of Austrolebias nigrofasciatus, an endemic and threatened annual killifish species of the Patos-Mirim lagoon system in Southern Brazil. In order to verify the effect of temperature on initial growth of A. nigrofasciatus, eggs stored in the laboratory were hatched and juveniles reared for eight weeks at 16 and 22 ºC. The standard length of newly hatched fishes was 4.67 ± 0.25 mm and after eight weeks they reached 23.68 ± 3.73 and 22.68 ± 5.36 mm, respectively at 16 and 22 ºC. However, initial growth of fish reared at 22 ºC was faster and they reached sexual dimorphism at an earlier age compared to those reared at 16 ºC. Final length of females reared at 22 ºC was 23.00 ± 2.83 mm, they were significantly larger than those reared at 16 ºC (17.91 ± 2.47 mm). Males were significantly larger than the females at 16 ºC, but there was no difference for growth between sexes of fish reared at 22 ºC. The sex ratios were 1:0.6 and 1:1.1 (M:F) at 16 ºC and 22 ºC, respectively, suggesting temperature determination of phenotypic sex. Considering the results, it appears that juveniles to be developed in captivity should be kept at 22 ºC during the first six weeks of life, thus ensuring a higher growth rate until puberty.

scholarly journals Analysis of Heavy-Chain Antibody Responses and Resistance to Parelaphostrongylus tenuis in Experimentally Infected Alpacas

2012 ◽  
Vol 19 (7) ◽  
pp. 1019-1026 ◽  
Author(s):  
S. R. Purdy ◽  
L. F. Gagliardo ◽  
S. Lefman ◽  
P. J. S. Hamel ◽  
S. Ku ◽  
...  
Keyword(s):  
Heavy Chain ◽  
Antibody Responses ◽  
Neurologic Disease ◽  
Content Type ◽  
Secondary Infections ◽  
Third Stage ◽  
Parelaphostrongylus Tenuis ◽  
Previous Infection ◽  
Heavy Chain Antibody ◽  
One Year

ABSTRACTThe parasitic nematodeParelaphostrongylus tenuisis an important cause of neurologic disease of camelids in central and eastern North America. The aim of this study was to determine whether alpacas develop resistance to disease caused byP. tenuisin response to a previous infection or a combination of controlled infection and immunization. Alpacas were immunized with a homogenate of third-stage larvae (L3) and simultaneously implanted subcutaneously with diffusion chambers containing 20 live L3. Sham-treated animals received adjuvant alone and empty chambers. The protocol was not effective in inducing resistance to oral challenge with 10 L3, and disease developed between 60 and 71 days following infection. Immediately following the onset of neurologic disease, affected animals were treated with a regimen of anthelmintic and anti-inflammatory drugs, and all recovered. One year later, a subset of alpacas from this experiment was challenged with 20 L3 and the results showed that prior infection induced resistance to disease. Primary and secondary infections induced production of conventional and heavy-chain IgGs that reacted with soluble antigens in L3 homogenates but did not consistently recognize a recombinant form of a parasite-derived aspartyl protease inhibitor. Thus, the latter antigen may not be a good candidate for serology-based diagnostic tests. Antibody responses to parasite antigens occurred in the absence of overt disease, demonstrating thatP. tenuisinfection can be subclinical in a host that has been considered to be highly susceptible to disease. The potential for immunoprophylaxis to be effective in preventing disease caused byP. tenuiswas supported by evidence of resistance to reinfection.

Numerical Simulation of Cavitation Bubble Growth within a Droplet

2015 ◽  
Vol 32 (2) ◽  
pp. 211-217 ◽  
Author(s):  
M. Lü ◽  
Z. Ning ◽  
K. Yan ◽  
J. Fu ◽  
C.-H. Sun
Keyword(s):  
Surface Tension ◽  
Growth Rate ◽  
Bubble Growth ◽  
Cavitation Bubble ◽  
Control Mechanism ◽  
Inertial Force ◽  
Viscous Force ◽  
Two Phase ◽  
Second Stage ◽  
Third Stage

ABSTRACTCavitation bubbles, which always exist in the diesel jet leaving the nozzle and in diesel droplets breaking up from the jet as a result of supercavitation of the diesel within the injection nozzle, increase the instability of jet and droplets in part due to the two-phase mixture, while the mechanism of this effect is still unclear. Cavitation bubble expansion within the diesel droplet has been simulated numerically based on the volume of fluid (VOF) method, and the control mechanism of bubble growth process is analyzed by Rayleigh-Plesset equation. The process of bubble growth is divided into three parts, including surface tension controlled domain, comprehensive competition controlled domain and inertial force controlled domain. During the first stage, cavitation bubble growth is controlled by the surface tension, and the decrease of the surface tension leads to the increase of the bubble growth rate. During the second stage, the bubble growth rate is controlled by the comprehensive competition of the surface tension, the inertial force and the viscous force. During the third stage, the process of bubble growth is majorly controlled by the inertial force.

scholarly journals Rearing of Milkfish, Chanos Chanos, in Net Cages at Sea at Various Stocking Densities

2007 ◽  
Vol 1 (2) ◽  
pp. 53
Author(s):  
Kusman Sumawidjaja ◽  
T. Yusdiana ◽  
Irzal Effendi ◽  
, Dharmadi
Keyword(s):  
Growth Rate ◽  
Survival Rate ◽  
Key Words ◽  
Stocking Density ◽  
Stocking Rate ◽  
Chanos Chanos ◽  
Feeding Efficiency ◽  
Final Length ◽  
Net Cage ◽  
Net Cages

<p>ABSTRACT</p><p>Stocking rate of milkfish, <em>Chanos chanos</em>, from 75 to 225 fish/m<sup>3 </sup> or from 1,33 to 3,98 kg/m<sup>3 </sup> did not affect the growth rate, survival rate, feeding efficiency, and final length and weight of fish, each at 2,32%/day, 81,8%, 63,8%, and 185,2 mm and 64,0 g respectively. Final biomass (Y) increased from 3,66 to 12,05 kg/m<sup>3</sup> with the increase of stocking rate (X) with Y = 0,056 X-0,45 (p&lt;0,05).</p><p>Key words :   Milkfish<em>, Chanos chanos</em>, floating net cage, stocking density.</p><p> </p><p>ABSTRAK</p><p>Padat penebaran ikan bandeng, <em>Chanos chanos</em>, dari 75 hingga 225 ekor/m<sup>3</sup> atau dari 1,33 hingga 3,98 kg/m<sup>3</sup> tidak mempengaruhi laju pertumbuhan, kelangsungan hidup, efisiensi pemberian pakan serta panjang dan bobot ikan akhir, masing-masing dengan rata-rata 2,32%/hari, 81,8%, 63,8%, 185,2 mm dan 64,0 g. Biomasa akhir (Y) meningkat dari 3,66 hingga 12,05 kg/m<sup>3</sup> dengan meningkatnya padat penebaran (X) dengan persamaan Y = 0,056 X -0,45 (p&lt;0,05).</p><p>Kata kunci :  Ikan bandeng, <em>Chanos chanos</em>, keramba jaring apung, padat penebaran</p>

Growth and adaptation to sea water in 'underyearling' sockeye (Oncorhynchus nerka) and coho (O. kisutch) salmon subjected to regimes of constant or changing temperature and day length

1978 ◽  
Vol 56 (11) ◽  
pp. 2413-2421 ◽  
Author(s):  
W. C. Clarke ◽  
J. E. Shelbourn ◽  
J. R. Brett
Keyword(s):  
Growth Rate ◽  
Environmental Factors ◽  
Constant Temperature ◽  
Sea Water ◽  
Rate Of Change ◽  
Day Length ◽  
Artificial Photoperiod ◽  
Final Length ◽  
Temperature Controlled ◽  
Rate Of Response

Growth and hypoosmoregulatory ability of 'underyearling' sockeye and coho were studied in relation to the influence of constant as well as changing temperature and day length. Both environmental factors influenced growth and osmoregulatory performance. Temperature controlled the rate of response to photoperiod so that changes in growth rate caused by photoperiod treatments were apparent sooner at higher temperatures than at lower ones. Changing temperatures did not alter the final length or weight achieved in comparison with a constant temperature of the same mean.The sensitivity of the fry to photoperiod varied seasonally. The characteristics of photoperiod which formed the most important cues were direction of change and rate of change of day length.It is concluded that artificial photoperiod treatments are not required to produce 'underyearling' sockeye smolts in spring, provided that water temperatures are sufficient to allow growth to a weight of 3–4 g. However, coho smoltify at a larger size and thus would require a substantially greater thermal input to produce 'underyearling' smolts in spring.

scholarly journals Telomere length is highly heritable and independent of growth rate manipulated by temperature in field crickets

2021 ◽  
Author(s):  
Jelle Boonekamp ◽  
Rolando Rodríguez‐Muñoz ◽  
Paul Hopwood ◽  
Erica Zuidersma ◽  
Ellis Mulder ◽  
...  
Keyword(s):  
Growth Rate ◽  
Telomere Length ◽  
Field Crickets

The threshold energy for atom displacement in fcc metals

1990 ◽  
Vol 48 (4) ◽  
pp. 530-531
Author(s):  
Wilfried Sigle ◽  
Matthias Hohenstein ◽  
Alfred Seeger
Keyword(s):  
Growth Rate ◽  
Elevated Temperatures ◽  
Threshold Energy ◽  
Dislocation Loops ◽  
Absolute Minimum ◽  
Voltage Electron ◽  
Atom Displacement ◽  
Electron Microscopes ◽  
Fcc Metal

Prolonged electron irradiation of metals at elevated temperatures usually leads to the formation of large interstitial-type dislocation loops. The growth rate of the loops is proportional to the total cross-section for atom displacement,which is implicitly connected with the threshold energy for atom displacement, Ed . Thus, by measuring the growth rate as a function of the electron energy and the orientation of the specimen with respect to the electron beam, the anisotropy of Ed can be determined rather precisely. We have performed such experiments in situ in high-voltage electron microscopes on Ag and Au at 473K as a function of the orientation and on Au as a function of temperature at several fixed orientations.Whereas in Ag minima of Ed are found close to <100>,<110>, and <210> (13-18eV), (Fig.1) atom displacement in Au requires least energy along <100>(15-19eV) (Fig.2). Au is thus the first fcc metal in which the absolute minimum of the threshold energy has been established not to lie in or close to the <110> direction.

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