A study of the development of dieldrin-resistance in relation to acaricide pressure in a population of Boophilus microplus

1964 ◽  
Vol 15 (3) ◽  
pp. 490 ◽  
Author(s):  
WJ Roulston
Keyword(s):  
Resistance Gene ◽  
Laboratory Tests ◽  
Tick Control ◽  
Boophilus Microplus ◽  
The Other ◽  
Acaricide Resistance ◽  
Property A ◽  
Irregular Distribution ◽  
Experimental Programme ◽  
The One

Dieldrin and aldrin preparations were used on separate properties where only arsenic had been used previously for tick control. Tick stocks from the properties before the commencement of the experiment showed no acaricide resistance. Dipping in dieldrin commenced on one property in November, and satisfactory control was obtained with the first three dippings at approximately 6-week intervals. After the fourth dipping, in late March, however, there was a marked survival of all stages of ticks, but particularly adults, although the vat concentration of dieldrin was almost as high as formerly and the deposits of the toxicant on the hair of the cattle were heavier. Progeny of female ticks which survived the fourth dipping were shown in laboratory tests to be highly resistant to dieldrin. Ticks present on the cattle at the fourth dipping could have included descendants of tick stocks which had undergone a maximum of four challenges with dieldrin, though most would have experienced only two to three. The fifth dipping was more effective than the fourth, which suggested irregular distribution of the dieldrin-resistant ticks in the pastures, possibly associated with periodical changes in the grazing of the cattle. The ticks present at the sixth dipping were highly resistant to dieldrin, and there was no protective period. Ticks from a culture established about 8 months after the inception of dipping were more than 900 times as resistant to dieldrin as the reference culture when tested by immersion. On another property a poor kill resulted from an initial dipping in 0.05% aldrin in early February, but high kills resulted from dippings in 0.10% aldrin in early March and early April. The tolerance of the ticks to aldrin after the conclusion of the experimental programme of five dippings was no higher than before its commencement. This could have been due to the fact that the reproducing populations of the tick received less severe and less frequent selection with the acaricide than during the course of the dieldrin trial. However, satisfactory results were still obtained by the owner with aldrin during the following tick season, and it is more likely that the contrasting results on the two properties were due to the presence of the resistance gene on the one property and its absence on the other.

The rate of loss of DDT on cattle in relation to protection from reinfestation by the cattle tick Boophilus microplus

1972 ◽  
Vol 23 (5) ◽  
pp. 735 ◽  
Author(s):  
HJ Schnitzerling ◽  
WJ Roulston ◽  
BF Stone ◽  
JT Wilson ◽  
PG Thompson
Keyword(s):  
Laboratory Tests ◽  
Boophilus Microplus ◽  
The Other ◽  
Cattle Tick ◽  
Cyclic Change ◽  
Minimum Period ◽  
The Mean

Australian Illawarra Shorthorn cattle were sprayed with 0.5% w/v DDT on 31 consecutive occasions at intervals of 4 weeks. Spraying was rotated amongst three groups of cattle. The rate of loss of DDT was determined on the barrel for all occasions and concurrently on the flank and escutcheon for the last 16 occasions. A protective period, defined as the minimum period cattle were protected against reinfestation by the cattle tick, was determined concurrently from observations made on the flank and escutcheon. A cyclic change in the rate of loss of DDT occurred on all sites. The rate was highest in summer and lowest in winter, and was in antiphase with corresponding changes in the protective period. The magnitude of the change of rate of loss of DDT was greater on the flank than on either the barrel or the escutcheon. The rate of loss from the three sites was always in the sequence flank > escutcheon > barrel. The mean deposits of DDT present on the flank and escutcheon when protection had just ceased were respectively 0.29 mg/g hair and 0.054 mg/sq. in., and the protective periods did not differ significantly. The protective period on the barrel was not measured, but it was calculated from data on the DDT deposits to be longer than on either of the other sites, even allowing for the fact that laboratory tests showed that DDT on barrel hair was relatively less effective against larvae than similar weights of DDT on flank hair.

Trapping of larvae of the cattle tick Boophilus microplus by Stylosanthes scabra under grazing conditions

1989 ◽  
Vol 40 (6) ◽  
pp. 1301 ◽  
Author(s):  
LJ Wilson ◽  
RW Sutherst ◽  
JD Kerr
Keyword(s):  
Laboratory Tests ◽  
Seasonal Pattern ◽  
Tick Control ◽  
Boophilus Microplus ◽  
Cattle Tick ◽  
Research Station ◽  
Morphological Attributes ◽  
Control Programs ◽  
Per Se ◽  
Stylosanthes Scabra

Several varieties of the leguminous genus Stylosanthes have the capacity to trap larvae of the tick Boophilus microplus. This capacity was assessed for S. scabra plants collected from grazed fields at two locations, Brian Pastures Research Station and 'The Springs' in central Queensland. Morphological attributes which may affect the capacity of plants to trap tick larvae were recorded. In laboratory tests, plants collected from Brian Pastures trapped 27% of larvae in summer and 12% in winter, whilst plants from 'The Springs' trapped an average of 12%, with no seasonal pattern discernible. The percentage of branches which were sticky was the major determinant of a plant's capacity to trap ticks. Variation in stickiness per se was less important. Frost and burning temporarily reduced tick-trapping capacity, but after four months, burnt plants trapped a higher percentage of larvae than unburnt plants due to the production of sticky regrowth. The implication of the results for the use of S. scabra in tick control programs is discussed.

In vitro Efficacy of Deltamethrin against Hyalomma anatolicum anatolicum

2019 ◽  
Vol 15 (01) ◽  
pp. 55-56
Author(s):  
Pratibha Thakur ◽  
R K Bagherwal ◽  
A K Jayraw ◽  
A K Soni
Keyword(s):  
Tick Control ◽  
Boophilus Microplus ◽  
Acaricide Resistance ◽  
Hyalomma Anatolicum Anatolicum ◽  
Nerve Ganglion ◽  
Cattle Health ◽  
College Farm

Tick and tick-borne diseases such as theileriosis,babesiosis, and Anaplasmosis pose a constant threato cattle health. Rhipicephalus (Boophilus) microplus andHyalomma anatolicum are the most commonly foundcattle tick species and cause significant economic lossesto dairy and leather industries by adversely affecting themilk production and quality of hides. Tick control strategyinvolves mainly the use of synthetic acaricides which resultsin the development of acaricide resistance. Deltamethrinacts on the parasites by contact and has strong lipophilicaction thus penetrates the cuticle nerve ganglion and block the motor activity. The presentstudy was aimed at the determination of in vitro efficacyof Deltamethrin against H. anatolicum ticks collected fromhealthy cattle of college farm and nearby dairy farms.

scholarly journals COMPARISON BETWEEN TURBIDITY MEASURED IN AN ESTUARY AND TURBIDITY CALCULATED FROM LABORATORY TESTS

2011 ◽  
Vol 1 (5) ◽  
pp. 28
Author(s):  
Andre Wallet
Keyword(s):  
Laboratory Tests ◽  
The Other ◽  
Scale Model ◽  
Seine Estuary ◽  
Direct Measurements ◽  
Hydraulic Conditions ◽  
Solid Discharge ◽  
Solid Transport ◽  
The One ◽  
The Relationship

The study of navigation conditions in the Seine estuary has led to scale model tests which are now being carried out by the NEYBPIC Laboratory, Grenoble; for the Port of Rouen Authority. In order to calibrate the model correctly, that is to say to ensure that the natural conditions would be reproduced on the model, it was necessary to carry out laboratory studies on the sand from the estuary bed to determine the solid discharge of this material for definite hydraulic conditions. This was necessary because, while at some distance above the bed direct measurements of the solid transport are relatively easy to make in nature by means of samples, they are practically impossible in the immediate neighborhood of the bottom when the sand is fine, as is the case in the Seine estuary. On the other hand, by taking certain precautions it is possible to measure the solid discharge in the immediate neighborhood of the bottom when.the transport of sand is studied in the laboratory. The two methods, direct measurements of the suspended load in nature and measurements of solid discharge near the bottom in the laboratory therefore complement one another. However, it seemed interesting to justify this method by comparing the results where nature and the laboratory coincide, i.e. for material in suspension. This paper gives details on the procedure followed for these laboratory tests on an experimental canal. The main results of these tests will be reviewed by examining the relationship between the concentration in the neighbourhood of the bottom and the solid discharge on the one hand, and the bottom shear stress on the other.

The management of acaricide resistance in the cattle tick, Boophilus microplus (Canestrini) (Acari: Ixodidae), in Australia

1979 ◽  
Vol 69 (3) ◽  
pp. 519-537 ◽  
Author(s):  
R. W. Sutherst ◽  
H. N. Comins
Keyword(s):  
Geographical Area ◽  
Optimal Strategies ◽  
Tick Control ◽  
Boophilus Microplus ◽  
Cattle Tick ◽  
Economic Factors ◽  
Acaricide Resistance ◽  
Development Of Resistance ◽  
High Concentrations

AbstractAn analysis, using mathematical models, is presented of the ecological, genetic and economic factors that determine the optimal strategies for the long-term use of chemical control of Boophilus microplus (Can.) on cattle. As an illustration, the control of the tick in south-eastern Queensland is considered, but the approach is readily applicable in any other geographical area. It is suggested that optimal strategies take into account the need to delay the development of resistance to acaricides. The suggested strategies involve the use of tick-resistant Zebu-type cattle as a basis for tick control. High concentrations of acaricides are recommended to reduce seleotion of resistant ticks. Careful timing and moderation in the use of acaricides is also recommended to minimise the number of occasions on which resistant ticks are subjected to selection at times when they can successfully reproduce. As the spread of resistance is thought to occur primarily on moving cattle and before resistance is evident, stringent quarantine measures may slow down the spread.

Races of Fusarium oxysporum f. sp. apii in California and their genetic interrelationships

1984 ◽  
Vol 62 (3) ◽  
pp. 546-550 ◽  
Author(s):  
John E. Puhalla
Keyword(s):  
Acid Phosphatase ◽  
Fusarium Oxysporum ◽  
Colony Size ◽  
Laboratory Tests ◽  
The Other ◽  
Vegetative Incompatibility ◽  
Race 1 ◽  
Race 2 ◽  
The One ◽  
Derivatives Of

Other researchers distinguished two races of Fusarium oxysporum f. sp. apii based on virulence tests; race 1 attacked only yellow celery varieties, whereas race 2 attacked both yellow and green types. In the present study, a third race, race 3, was found which attacked only green celery. Three laboratory tests were devised that identified these three races without recourse to virulence tests. The laboratory-based criteria included colony size on a sorbose-containing medium, allozymic differences for the enzyme acid phosphatase, and heterokaryon, or vegetative, incompatibility. These laboratory tests also tentatively defined two additional races, 2E and 3E, and they indicated that some avirulent strains isolated from celery were attenuated variants of all three races. Race 1 was clearly unrelated to race 2, and therefore the one did not arise from the other. However, races 2 and 3 appeared to be closely related. Strains of these two races were genetically very homogeneous and could be clonal derivatives of a single progenitor. Races 1 and 2E, however, each represented a group of genetically diverse strains. So far only races 2 and 3 have been found in California.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

The Reliability of Retrieval-Induced Forgetting

2012 ◽  
Vol 17 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Rosalind Potts ◽  
Robin Law ◽  
John F. Golding ◽  
David Groome
Keyword(s):  
Individual Differences ◽  
Recognition Test ◽  
Laboratory Tests ◽  
The Other ◽  
Clinical Factors ◽  
Test Items ◽  
T1 And T2 ◽  
Test Materials ◽  
Induced Forgetting

Retrieval-induced forgetting (RIF) refers to the finding that the retrieval of an item from memory impairs the retrieval of related items. The extent to which this impairment is found in laboratory tests varies between individuals, and recent studies have reported an association between individual differences in the strength of the RIF effect and other cognitive and clinical factors. The present study investigated the reliability of these individual differences in the RIF effect. A RIF task was administered to the same individuals on two occasions (sessions T1 and T2), one week apart. For Experiments 1 and 2 the final retrieval test at each session made use of a category-cue procedure, whereas Experiment 3 employed category-plus-letter cues, and Experiment 4 used a recognition test. In Experiment 2 the same test items that were studied, practiced, and tested at T1 were also studied, practiced, and tested at T2, but for the remaining three experiments two different item sets were used at T1 and T2. A significant RIF effect was found in all four experiments. A significant correlation was found between RIF scores at T1 and T2 in Experiment 2, but for the other three experiments the correlations between RIF scores at T1 and T2 failed to reach significance. This study therefore failed to find clear evidence for reliable individual differences in RIF performance, except where the same test materials were used for both test sessions. These findings have important implications for studies involving individual differences in RIF performance.

Stories and the Self

2020 ◽  
Vol 32 (2) ◽  
pp. 47-58 ◽  
Author(s):  
Stefan Krause ◽  
Markus Appel
Keyword(s):  
Meta Analysis ◽  
The Self ◽  
The Other ◽  
Lower Degree ◽  
Contrast Effects ◽  
Self Perception ◽  
Self Perceptions ◽  
Other Hand ◽  
The One ◽  
Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome

2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann
Keyword(s):  
Acute Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Primary Tumour ◽  
The Other ◽  
Haematopoietic Stem Cell ◽  
Other Hand ◽  
Primary Reduction ◽  
The One ◽  
Acute Myeloid

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

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