A method for measuring the acaricide-susceptibility of the cattle tick Boophilus microplus (Can.)

A simple method is described of testing the susceptibility to acaricides of larvae of the cattle tick Boophilus microplus (Can.) in Queensland, Australia, by enclosing them in packets made from rectangular filter papers, folded once and secured along the remaining three sides by spring clips, that had been impregnated with Risella-oil solutions of DDT, dieldrin, or Bayer 21/199 (coumaphos), or with deposits from xylene solutions of Dilan. The response of susceptible engorged adult females to dieldrin was tested similarly. Five out of six experiments showed statistical evidence of repeatability of results in determination of relative DDT-resistance of larvae. There was a slight increase in susceptibility of non-resistant larvae to DDT with increasing age between 7 and 28 days for fresh packets but not for re-used packets. In three out of four tests, re-used packets were significantly more toxic (up to 1·40 times) to susceptible larvae than fresh packets. In one test a loss of toxicity occurred after storage of Bayer 21/199 packets for 23 days. The possible use of this method for measuring resistance in ticks is discussed.

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The inheritance of DDT-resistance in the cattle tick, Boophilus microplus

Australian Journal of Agricultural Research ◽

10.1071/ar9620984 ◽

1962 ◽

Vol 13 (5) ◽

pp. 984 ◽

Cited By ~ 15

Author(s):

BF Stone

Keyword(s):

Resistant Strain ◽

Reference Strain ◽

Boophilus Microplus ◽

Autosomal Gene ◽

Cattle Tick ◽

Adult Females ◽

Ddt Resistance ◽

High Level ◽

Multiresistant Strain

Adults of a DDT-resistant strain of the cattle tick from central Queensland were crossed with adults of a susceptible reference strain, by means of cardboard mating boxes glued to the skins of cattle. F1, backcross, and F2 larvae were tested for resistance to DDT by enclosure of larvae in filter paper packets impregnated with oil solutions of pp'-DDT. F1 and backcross engorged adult females were tested for resistance by injection with oil solutions of pp'-DDT. There was no evidence of departure from a 1 : 1 ratio in the backcrosses or from a 1 : 2 : 1 ratio in the F2, and there was little difference between the compositions of the F1 reciprocal crosses or among the backcrosses derived from them. Therefore DDT resistance in this strain was considered to be due to a single, incompletely recessive, autosomal gene. Engorged nymphs of the resistant strain moulted later in vitro than nymphs of the susceptible strain, and resistant engorged adult females detached from the host later than susceptible engorged adult females. After 13 generations of DDT-free culturing of a multiresistant strain, the percentage of homozygous DDT-resistant ticks in the strain had fallen from a high level to about 55%. This figure remained constant for a further 10 generations.

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Biocidal potential of Eugenia pyriformis essential oil in the control of Rhipicephalus (Boophilus) microplus in the free-living cycle

Pesquisa Veterinária Brasileira ◽

10.1590/1678-5150-pvb-6434 ◽

2019 ◽

Vol 39 (11) ◽

pp. 879-888

Author(s):

Jaqueline P. Medeiros ◽

Wanessa C. Bortollucci ◽

Eloisa S. Silva ◽

Herika L.M. Oliveira ◽

Caio F.A.A. Campo ◽

...

Keyword(s):

Essential Oil ◽

Immersion Test ◽

Probit Analysis ◽

Boophilus Microplus ◽

Control Measures ◽

Cattle Tick ◽

Free Living ◽

Adult Females ◽

Southern Cattle Tick ◽

Cattle Herds

ABSTRACT: Brazil has one of the largest commercial cattle herds in the world, which naturally coexist with an enormous number of parasitic species. Southern cattle tick, Rhipicephalus (Boophilus) microplus, is among these species, interfering with animal productivity and causing losses to the beef and dairy cattle sector. The use of chemical acaricides in the control of this mite has resulted in the emergence of resistant populations. In this sense, alternative control measures using plants as sources of botanical acaricides have shown to be effective. Eugenia pyriformis Cambess is a Brazilian plant with antioxidant and antimicrobial activity; however, there are no reports on its acaricidal activity in the literature. The present study aimed to evaluate the acaricidal and larvicidal potential of E. pyriformis leaf essential oil (EO) on southern cattle tick at different stages of the reproductive cycle. E. pyriformis leaves were collected and dried, and had their EO extracted by hydrodistillation (3h) using a modified Clevenger apparatus. Chemical analysis was performed by gas chromatography coupled with mass spectrometry (GC/MS), and 32 compounds belonging to the sesquiterpene class were identified: hydrocarbons (17.98%) and oxygenated forms (81.96%), with spathulenol (43.65%) and caryophyllene oxide (12.17%) as the most common. The EO was evaluated by the Adult Immersion Test at the concentrations (500.00 to 3.12mg/mL) in which the following parameters were measured: mortality of females (%), hatchability of eggs (%), and product efficiency (%). Larvae were assessed by the Larval Packet Test at concentrations ranging from 25.00 to 0.00004mg/mL. Lethal concentrations (LC) required for killing 50 and 99.9% of adult females and larvae were determined using Probit analysis. LC50 and LC99.9 of EO were 0.06 and 24.60mg/mL and 1,208.80 and 2,538mg/mL for larvae and adult females, respectively. Action of the EO in the free-living cycle of R. (B.) microplus larvae was another parameter assessed. To this end, the larvae were deposited in pots containing Brachiaria decumbens and, after migration to the leaf apex, a solution containing LC99.9 (24.60mg/mL) of the EO was sprayed. After 24h, 72.25% of the larvae had died, indicating stability of the EO when subjected to uncontrolled temperature and humidity conditions. The mechanism of action through which the EO killed the larvae and adult females was investigated by the Bioautographic Method, which showed inhibition of 3.15mg/mL of the EO on the acetylcholinesterase (AChE) enzyme. The results found in the present experiment indicate that E. pyriformis essential oil is an alternative in the control of southern cattle tick in the larval (parasitic) and free-living cycle (non-parasitic) stages under field conditions.

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The inheritance of dieldrin-resistance in the cattle tick, Boophilus microplus

Australian Journal of Agricultural Research ◽

10.1071/ar9621008 ◽

1962 ◽

Vol 13 (5) ◽

pp. 1008 ◽

Cited By ~ 12

Author(s):

BF Stone

Keyword(s):

Filter Paper ◽

Reference Strain ◽

Boophilus Microplus ◽

Autosomal Gene ◽

Cattle Tick ◽

Laboratory Population ◽

Reciprocal Crosses ◽

Adult Females ◽

Multiresistant Strain

Adults of a dieldrin-resistant straiu of cattle tick from southern Queensland were crossed with adults of a susceptible reference strain, by means of cardboard mating boxes glued to the skins of cattle. The F1 and backcross larvae were tested for resistance by enclosure in filter paper packets impregnated with oil solutions of dieldrin. The corresponding engorged adult females were tested by injection with oil solutions of dieldrin. There was no evidence of significant departure from a 1 : 1 ratio of resistant and susceptible phenotypes in the backcrosses, and there was little difference between the composition of the F1 reciprocal crosses or between the backcrosses derived from them. Dieldrin-resistance in this strain appears to be due to a single, dominant autosomal gene. Dieldrin-resistant ticks in a multiresistant strain from central Queensland steadily declined from 50–60% to an undetectable percentage in a laboratory population bred in the absence of dieldrin for 24 generations.

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Evaluation of activity of the crude ethanolic extract of Magonia pubescens St. Hil (Sapindaceae) against larvae of the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae)

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132008000600009 ◽

2008 ◽

Vol 51 (6) ◽

pp. 1147-1152 ◽

Cited By ~ 8

Author(s):

Fernando de Freitas Fernandes ◽

Priscilla Antunes Diógenes Bessa ◽

Edméia de Paula e Souza Freitas

Keyword(s):

Filter Paper ◽

Ethanolic Extract ◽

Boophilus Microplus ◽

Cattle Tick ◽

Distilled Water ◽

Significant Mortality

The acaricidal potential of the crude ethanolic extract (c.e.e.) of the stem peel of Magonia pubescens was evaluated against larvae of Rhipicephalus (Boophilus) microplus. The larvae were placed in filter paper envelopes impregnated with different concentrations of c.e.e., dissolved in dimethylsulfoxide (DMSO) and distilled water for determination of lethal concentrations (LC). The following treatments were used: 1. Envelopes of dry filter paper; 2. Envelopes of filter paper moistened with distilled water; 3. Envelopes of filter paper moistened with a solution of DMSO in distilled water; and 4. Envelopes moistened with 2 mL of each concentration of the c.e.e. to be tested. The bioassays were carried out in quadruplicate at 27°±1° C and RH e"80% and 12h light. Mortality was observed after 48 h, LC50 and LC99 values of 365 and 4,000 ppm being obtained. There was no significant mortality in larvae exposed to the first three treatments (p < 0.05).

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Heparan sulfate glycosaminoglycan expression in the intestinal tract and ovary of fully engorged adult females of the cattle tick Boophilus microplus and in their laid eggs

Molecular and Biochemical Parasitology ◽

10.1016/s0166-6851(03)00169-5 ◽

2003 ◽

Vol 130 (2) ◽

pp. 163-166 ◽

Cited By ~ 5

Author(s):

Glaucia R Onofre ◽

Flávio A Lara ◽

Pedro L Oliveira ◽

Luiz-Claudio F Silva

Keyword(s):

Heparan Sulfate ◽

Intestinal Tract ◽

Boophilus Microplus ◽

Cattle Tick ◽

Adult Females

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Radioactive studies on the feeding of larvae, nymphs, and adults of the cattle tick,Boophilus microplus(Canestrini)

Parasitology ◽

10.1017/s0031182000069444 ◽

1968 ◽

Vol 58 (2) ◽

pp. 415-430 ◽

Cited By ~ 23

Author(s):

G. W. Seifert ◽

P. H. Springell ◽

R. J. Tatchell

Keyword(s):

Life Cycle ◽

Technical Assistance ◽

Boophilus Microplus ◽

Red Cells ◽

Cattle Tick ◽

Blood Components ◽

Larval Stages ◽

Adult Females ◽

Host Blood ◽

Radioactivity Levels

The erythrocytes and plasma of a British and Brahman crossbred steer were labelled with51Cr and125I respectively. The radioactivity levels were subsequently maintained as constant as feasible by injecting the steers with calculated amounts of the appropriate labelled material on 3 consecutive days. The steers had previously been heavily infested withBoophilus microplusto ensure that all stages in the parasite's life-cycle would be present during the 4-day period, when the steers were being treated with isotopes.Various stages ofB. micropluslarvae, nymphs and adults were collected and the uptake of red cells and plasma at each stage assessed by radioassay. In certain calculations, corrections were made for the uptake of blood fractions before the animals were made radioactive.A relationship between the weight of the tick and its dietary intake was established. At all the stages of larval and nymphal feeding the plasma content of the diet was greater than that of the host blood. However, erythrocytes were detectable even in the earliest larval stages examined. Dropped fully engorged adult females contained more red cells per individual, and generally also more plasma, than engorged ticks removed from the host.Fully engorged adult females took up as much as twice their own weight of blood components, but in none of the earlier stages did the tick concentrate its blood meal.No obvious differences could be demonstrated statistically between the behaviour of the parasites on the two hosts. However, indications are that recently attached larvae took up more erythrocytes from the British animal.We wish to thank Messrs A. K. Duffield, A. J. Short, B. Wilson, and Miss S. J. Shepherd, for skilful technical assistance.

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Cattle ticks, Boophilus microplus, resistant to DDT, BHC, and Dieldrin

Australian Journal of Agricultural Research ◽

10.1071/ar9600106 ◽

1960 ◽

Vol 11 (1) ◽

pp. 106 ◽

Cited By ~ 7

Author(s):

BF Stone ◽

LG Webber

Keyword(s):

Reference Strain ◽

Previous History ◽

Boophilus Microplus ◽

Injection Method ◽

Adult Females ◽

Cattle Ticks ◽

History Of ◽

Ddt Resistance

Cattle ticks on a property in central Queensland, where there had been a previous history of DDT-resistance, were not readily controlled by dipping infested cattle in 0.05 per cent. w/v gamma-BHC or 0.05 per cent. w/v dieldrin after these chemicals had been in use for 10 and 4 months respectively. Spraying of steers artificially infested with ticks taken from this property 9 months later, indicated resistance to DDT and dieldrin, but not to "Diazinon". Immersion tests with larvae and engorged adult females of this strain showed them to be respectively about 9 and 20 times as resistant to DDT as those of a susceptible reference strain. The engorged females were shown to be more than 700 times as resistant to dieldrin. When tested by an injection method, the engorged adult females of this strain showed a resistance to DDT and dieldrin of 5 and 12 times respectively, some resistance to BHC, but no resistance to Bayer 21/199. Similarly tested engorged adult females of another strain taken from the property 15 months later showed a resistance to DDT of 8 times.

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Resistance to DDT in the catle trick, Boophilus microplus (Canestrini)

Australian Journal of Agricultural Research ◽

10.1071/ar9570424 ◽

1957 ◽

Vol 8 (4) ◽

pp. 424 ◽

Cited By ~ 14

Author(s):

BF Stone

Keyword(s):

Resistant Strain ◽

Boophilus Microplus ◽

Susceptible Strain ◽

Cattle Tick ◽

Three Generations ◽

Adult Females ◽

Selection For

Difficulty was experienced in controlling the cattle tick, on a herd at Rockhampton in central Queensland, by dipping in 0.5 per cent. w/v pp'-DDT. When an animal artificially infested with this strain was sprayed with 1 per cent. w/v pp'-DDT, only 26 per cent. of the engorged females falling from the animal over the 48-hr period after spraying failed to lay viable eggs, as compared with 64 per cent. of susceptible ticks falling from a similarly treated aninial. Both strains were, however, equally susceptible to "Diazinon". Laboratory concentration-response tests with a culture of the Rockhampton ticks indicated that the larvae exhibited a resistance 22 times that of a susceptible strain, and the engorged adult females a degree of resistance probably of the same order. The Rockhampton strain showed no significant resistance to dieldrin or toxaphene. There was no difference in susceptibility to DDT between adults of an 'early-falling' and a "late-falling" substrain of the resistant strain after selection for three generations.

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Biochemical Genetics of Resistance to Organophosphorus Acaricides in Three Strains of the Cattle Tick, Boophilus microplus

Australian Journal of Biological Sciences ◽

10.1071/bi9760265 ◽

1976 ◽

Vol 29 (3) ◽

pp. 265 ◽

Cited By ~ 11

Author(s):

Bernard F Stone ◽

James Nolan ◽

Charles A Schuntner

Keyword(s):

Ache Activity ◽

Reference Strain ◽

Organophosphorus Compounds ◽

Boophilus Microplus ◽

Cattle Tick ◽

Biochemical Genetics ◽

Genetics Of Resistance ◽

Adult Females ◽

Degree Of Dominance ◽

Brain Ache Activity

Three aspects of the biochemical genetics of resistance to organophosphorus compounds in the Biarra (B), Mackay (M) and Ridgelands (R) strains of the cattle tick B. microp/us were studied. These were: decreased acetylcholinesterase (AChE) activity in adult brains of strains Band M; decreased AChE sensitivity to inhibitors in adult brains and in larvae of strains B, M and R; and increased detoxication in larvae and adult females of strain M. Comparisons were made with a susceptible reference strain (S). Microspectrophotometric estimations of AChE activity in histochemical preparations of whole brains showed that hybrids had levels of activity approximately intermediate between those of the parental strains. Homogenates of brains from hybrids assayed biochemically gave similar but more precise results which indicated that decreased brain AChE activity was neither recessive nor dominant (degree of dominance, D = + O� 02) in strain B and incompletely recessive (D = - O� 26) in strain M. The proportions of brains showing decreased AChE activity in testcross and F 2 progenies indicated that decreased AChE activity in strains Band M is controlled by single autosomal genes.

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