A ten-year review of commercial vaccine performance for control of tick infestations on cattle

2007 ◽  
Vol 8 (1) ◽  
pp. 23-28 ◽  
Author(s):  
José de la Fuente ◽  
Consuelo Almazán ◽  
Mario Canales ◽  
José Manuel Pérez de la Lastra ◽  
Katherine M. Kocan ◽  
...  

AbstractTicks are important ectoparasites of domestic and wild animals, and tick infestations economically impact cattle production worldwide. Control of cattle tick infestations has been primarily by application of acaricides which has resulted in selection of resistant ticks and environmental pollution. Herein we discuss data from tick vaccine application in Australia, Cuba, Mexico and other Latin American countries. Commercial tick vaccines for cattle based on the Boophilus microplus Bm86 gut antigen have proven to be a feasible tick control method that offers a cost-effective, environmentally friendly alternative to the use of acaricides. Commercial tick vaccines reduced tick infestations on cattle and the intensity of acaricide usage, as well as increasing animal production and reducing transmission of some tick-borne pathogens. Although commercialization of tick vaccines has been difficult owing to previous constraints of antigen discovery, the expense of testing vaccines in cattle, and company restructuring, the success of these vaccines over the past decade has clearly demonstrated their potential as an improved method of tick control for cattle. Development of improved vaccines in the future will be greatly enhanced by new and efficient molecular technologies for antigen discovery and the urgent need for a tick control method to reduce or replace the use of acaricides, especially in regions where extensive tick resistance has occurred.

2016 ◽  
Vol 11 (12) ◽  
pp. 1934578X1601101
Author(s):  
Nicolas Lebouvier ◽  
Thomas Hue ◽  
Joseph Brophy ◽  
Edouard Hnawia ◽  
Mohammed Nour

Essential oil from leaves of Nemuaron vieillardii (Baill.) Baill., a shrub used in the kanak pharmacopeia, was analyzed by gas chromatography and combined gas chromatography-mass spectrometry. The main compounds identified were safrole (49.7%), linalool (8.0%), δ-cadinene (5.1%), caryophyllene oxide (4%) and α-copaene (2.4%). This chemical composition is consistent with leaf oils of the Atherospermataceae family and demonstrates the proximity of the two genera Nemuaron and Atherosperma as regards to their essential oil compositions. The modified Larval Packet Test (LPT) was used to assess acaricidal effect of N. vieillardii essential oil on larvae of the cattle tick Rhipicephalus (Boophilus) microplus and LC50 was then calculated to 14.67%. High content of safrole in this oil which is suspected of being a human carcinogen, poses the problem of the use of this oil in a perspective of development of alternative tick control strategy and in the traditional medicinal consumption of Nemuaron vieillardii.


1962 ◽  
Vol 13 (5) ◽  
pp. 974 ◽  
Author(s):  
PR Wilkinson

Weekly counts of Boophilus microplus (Canestrini) on 30 Australian Illawarra Shorthorn heifers enabled the cattle to be ranked in order of tick infestation, with highly significant correlations between counts of two observers and between counts of one observer on different occasions. In May 1960, when the heifers were 1½–2 years old, 12 were selected as relatively tick-resistant and 12 as relatively tick-susceptible. Each of these groups was divided at random into herds of six, and the four herds were then allotted randomly to separate paddocks, each onequarter of the area previously grazed. A herd was sprayed with 0.5% DDT emulsion when its average count of ticks (adult females over 5 mm in length) on one side of the animals exceeded 40. During the ensuing tick season, from October 5, 1960, to June 7, 1961, the sums of average weekly tick counts, and the numbers of sprayings (in parenthesis) were: susceptible herds 4853 (5) and 5962 (6): resistant herds 718 (0) and 1073 (1). Counts of tick larvae on defined body areas showed that, in the summer after segregation, resistant herds carried fewer larvae than the susceptible herds, apparently because fewer mature ticks fell from the resistant cattle in the preceding spring and winter. As a consequence of this, counts of adult ticks were comparatively lower after than before segregation. There was little or no 'spring rise' of tick infestation on the resistant herds. There was no significant correlation between tick resistance and coat score, sweat gland dimensions, or total skin thickness, but a correlation of -0.53 with follicle depth was significant at the 1% level. There was no evidence of adaptation of cattle ticks to the resistant animals, either in the field experiment or in observations on stalled cattle. The experiment draws attention to the appreciable proportion of tick-resistant animals within the Australian Illawarra Shorthorn breed, which has largely been overlooked in past discussions on tick-resistant breeds of cattle. It also suggests a technique for estimating the improvement in tick control that may be obtained by a given degree of selection within any breed, for any given environment.


2019 ◽  
Vol 59 (8) ◽  
pp. 1401 ◽  
Author(s):  
Heather M. Burrow ◽  
Ben J. Mans ◽  
Fernando F. Cardoso ◽  
Michael A. Birkett ◽  
Andrew C. Kotze ◽  
...  

About 80% of the world’s cattle are affected by ticks and tick-borne diseases, both of which cause significant production losses. Cattle host resistance to ticks is the most important factor affecting the economics of tick control, but it is largely neglected in tick-control programs due to technical difficulties and costs associated with identifying individual-animal variation in resistance. The present paper reviews the scientific literature to identify factors affecting resistance of cattle to ticks and the biological mechanisms of host tick resistance, to develop alternative phenotype(s) for tick resistance. If new cost-effective phenotype(s) can be developed and validated, then tick resistance of cattle could be genetically improved using genomic selection, and incorporated into breeding objectives to simultaneously improve cattle productive attributes and tick resistance. The phenotype(s) could also be used to improve tick control by using cattle management. On the basis of the present review, it is recommended that three possible phenotypes (haemolytic analysis; measures of skin hypersensitivity reactions; simplified artificial tick infestations) be further developed to determine their practical feasibility for consistently, cost-effectively and reliably measuring cattle tick resistance in thousands of individual animals in commercial and smallholder farmer herds in tropical and subtropical areas globally. During evaluation of these potential new phenotypes, additional measurements should be included to determine the possibility of developing a volatile-based resistance phenotype, to simultaneously improve cattle resistance to both ticks and biting flies. Because the current measurements of volatile chemistry do not satisfy the requirements of a simple, cost-effective phenotype for use in commercial cattle herds, consideration should also be given to inclusion of potentially simpler measures to enable indirect genetic selection for volatile-based resistance to ticks.


1957 ◽  
Vol 8 (4) ◽  
pp. 414 ◽  
Author(s):  
PR Wilkinson

When two comparable herds of cattle were kept continuously in adjoining paddocks, frequent acaricidal treatment was necessary to control ticks (Boophilus microplus (Canestrini) ). Thereafter, one of the two herds was grazed alternately in its own and an adjacent paddock, the intervals between each transfer being sufficient to ensure that most of the ticks in the unoccupied paddock had died. Tick infestations on this herd were greatly reduced, and less frequent use of acaricides was necessary. The herd remaining in the continuously stocked pasture continued to need acaricidal treatment for recurring tick infestation. In a field trial with 350–400 cattle moved a t intervals to each of three formerly heavily infested paddocks, tick infestations remained very light, although the herd was dipped only In January, September, and the following January. A control herd on continuously stocked pasture, treated at the owner's discretion, required eight dippings in this period. This procedure of "pasture spelling" seems likely to be widely applicable in central Queensland.


2018 ◽  
Vol 6 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Gustavo Alfonso Barrera

Entrepreneurship has become a fundamental theme in Latin America. In recent years, public and private institutions have invested in training entrepreneurs in order to contribute to economic growth, develop work and reduce poverty. In the presented research, it is compared the self-appraisal as innovators, of micro-entrepreneurs who have attended training during the last five years, with micro-entrepreneurs without training, and additionally, it is studied if the micro-entrepreneurs that self-perceive themselves as innovators are more prone to hiring workers and obtain higher profits. The methodology used is hypothesis testing with Chi2 statistic and descriptive statistics. The results exhibit that trained micro-entrepreneurs call themselves innovators in greater proportion and that this relationship is more relevant in some training topics, moreover, that innovative self-perception is linked to a greater intention of hiring and profits. The evidence obtained is considered relevant, since it allows orienting training activities in Latin American countries and improving the selection of topics and methodologies to promote their effectiveness.


1989 ◽  
Vol 40 (6) ◽  
pp. 1301 ◽  
Author(s):  
LJ Wilson ◽  
RW Sutherst ◽  
JD Kerr

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.


1966 ◽  
Vol 17 (3) ◽  
pp. 387 ◽  
Author(s):  
KLS Harley

Survival of the non-parasitic stages of the cattle tick, Boophilus microplus (Canestrini), has been investigated over a period of 5 years in 25, 40, and 80 in. rainfall districts of north Queensland. Engorged ticks were exposed regularly in field plots and in Stevenson screens, and the times of egg hatchmg (prehatch period) and periods of survival of the larvae were observed. The prehatch period in the three districts followed the same pattern and was related to seasonal temperature changes, varying from less than 4 weeks in midsummer to over 13 weeks in midwinter. A relationship between minimum prehatch period and mean air temperature for ticks exposed in screens was established, but the data from ticks exposed in the field were too variable to establish a relationship between prehatch periods and soil temperatures. Hatching was recorded in every month of the year from all districts, but during the driest months in the 25 in. rainfall areas many ticks in exposed situations failed to reproduce. Larval survival and total longevity also followed a similar pattern in all districts. The longest survival periods were recorded for the progeny of ticks exposed late in the wet season from March to April, and the shortest survival periods for the progeny of ticks exposed during the dry season from August to September. Mean maximum total longevity for ticks exposed in field plots in the 25 in. rainfall district varied from 10 to 22 weeks, in the 40 in. rainfall district from 14 to 22 weeks, and in the 80 in. rainfall district from 15 to 26 weeks. The data on prehatch and survival periods are a suitable basis for formulating recommendations for tick control by pasture spelling and planned dipping.


2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
H. Aguilar-Díaz ◽  
M. Esquivel-Velázquez ◽  
R. E. Quiroz-Castañeda ◽  
E. Miranda-Miranda ◽  
R. J. P. Conde-Baeye ◽  
...  

The cattle tick Rhipicephalus (Boophilus) microplus is one of the most harmful ectoparasites affecting bovines worldwide. It represents a major threat to livestock industry due to the economic losses caused and diseases associated with these ticks. The most important tick control strategy has been the use of ixodicides, resulting in chemically resistant tick populations. It is necessary to understand the mechanisms that result in resistance so as to create new strategies increasing the lifespan of ixodicides or finding alternative targets to produce new acaricides. In this paper, in order to obtain an insight into the mechanisms that govern ixodicides resistance, we will compare the hemolymph proteome of two tick R. microplus strains, one susceptible (MJ) and one resistant (SA) to ixodicides, using HPLC and 2D electrophoresis. Significant differences were found in protein content between strains using HPLC. 2D electrophoresis revealed that 68 hemolymph protein spots were common between strains; however, 26 spots were unique to the susceptible strain MJ and 5 to the resistant strain SA. The most distinctive protein spots on the preparative gels were selected for further analyses. Nine protein spots were identified by mass fingerprinting, 
revealing proteins that may have a role in the ixodicides resistance or susceptibility. In this paper, we present the tick hemolymph proteome revealing a set of proteins which suggest a possible role in tick detoxification.


2021 ◽  
pp. 1-31
Author(s):  
Karel Kouba ◽  
Jan Pumr

Abstract Despite theoretical arguments suggesting the strong effects of presidential term limits and re-election on democracy, there is surprisingly little empirical evidence to evaluate them. We test both the effect on democracy of the existence of a consecutive re-election rule and of reforms introducing it for incumbent presidents. Using evidence from Latin American countries between 1945 and 2018, we test their relationship to both vertical and horizontal accountability. A synthetic control method is employed to account for the effect of term-limit reforms, and time-series cross-section models for modelling the association with the re-election rule. Both vertical and horizontal accountability as well as the quality of democracy are eroded by term-limit evasion reforms in most countries and strengthened in none between 1990 and 2018. Allowing presidents to run for re-election – relative to term-limited ones – is consistently associated with weak democratic outcomes.


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