scholarly journals STRUCTURE-ACTIVITY STUDIES ON ANALOGUES OF 4-METHYLGUAIACOL, A CATTLE ANAL ODOUR CONSTITUENT REPELLENT TO THE BROWN EAR TICK (Rhipicephalus appendiculatus)

2018 ◽  
Author(s):  
Margaret W. Kariuki ◽  
Ahmed Hassanali ◽  
Margaret M. Ng’ang’a
Keyword(s):  
Rhipicephalus Appendiculatus ◽  
Major Constituent ◽  
Feeding Site ◽  
Phenolic Oxygen ◽  
Structure Activity ◽  
Varying Length ◽  
Ear Tick ◽  
Set Up ◽  
Climbing Assay ◽  
Different Doses

AbstractPreviously, 4-methylguaiacol, a major constituent of cattle anal odour, was found to have a high repellence on Rhipicephalus appendiculatus. In the present study, 10 structural analogues of the phenol were tested for repellence against R. appendiculatus in order to assess the effects of (i) absence or presence of the 4-alkyl group of varying length, (ii) inclusion of a double bond in the 4-alkyl chain, (iii) linking the two phenolic oxygen in a methylenedioxy bridge, (iv) replacement of the OCH3 with CH3 and inclusion of another CH3 at position 6, and (v) presence of an additional OCH3 group at position 6. The analogues comprised of 2-methoxyphenol (guaiacol), 4-ethyl-2- methoxyphenol, 4-propyl-2-methoxyphenol, 4-allyl-2-methoxyphenol (eugenol), 3,4-methylenedioxytoluene, 2,4- dimethylphenol, 4-ethyl-2-methylphenol, 2,4,6-trimethylphenol, 4-propyl-2,6-dimethoxy-phenol and 4-allyl-2,6- dimethoxyphenol, which were compared at different doses in a two-choice climbing assay set up. Each analogue showed either increased or reduced repellence compared with 4-methylguaiacol. The structural feature that was associated with the highest repellence was 4-propyl moiety in the guaiacol unit (RD75 = 0.031 for 4-propyl-2- methoxyphenol; that of 4-methylguaiacol = 0.564). Effects of blending selected analogues with high repellence were also compared. However, none of the blends showed incremental increase in repellence compared with that of 4- propyl-2-methoxyphenol. We are currently evaluating the effects of controlled release of the compound at different sites on cattle on the behavior and success of R. appendiculatus to locate their predilection feeding site.

scholarly journals Repellent Activities of Essential Oils of Some Plants Used Traditionally to Control the Brown Ear Tick,Rhipicephalus appendiculatus

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Wycliffe Wanzala ◽  
Ahmed Hassanali ◽  
Wolfgang Richard Mukabana ◽  
Willem Takken
Keyword(s):  
Essential Oils ◽  
Rhipicephalus Appendiculatus ◽  
Tithonia Diversifolia ◽  
Ethnobotanical Survey ◽  
Traditional Use ◽  
Western Kenya ◽  
Tagetes Minuta ◽  
Ear Tick ◽  
Climbing Assay ◽  
Study Dose

Essential oils of eight plants, selected after an ethnobotanical survey conducted in Bukusu community in Bungoma County, western Kenya (Tagetes minuta, Tithonia diversifolia, Juniperus procera, Solanecio mannii, Senna didymobotrya, Lantana camara, Securidaca longepedunculata, andHoslundia opposita), were initially screened (at two doses) for their repellence against brown ear tick,Rhipicephalus appendiculatus, using a dual-choice climbing assay. The oils ofT. minutaandT. diversifoliawere then selected for more detailed study. Dose-response evaluations of these oils showed thatT. minutaoil was more repellent (RD50= 0.0021 mg) than that ofT. diversifolia(RD50= 0.263 mg). Gas chromatography-linked mass spectrometric (GC-MS) analyses showed different compositions of the two oils.T. minutaoil is comprised mainly ofcis-ocimene (43.78%), dihydrotagetone (16.71%), piperitenone (10.15%),trans-tagetone (8.67%), 3,9-epoxy-p-mentha-1,8(10)diene (6.47%),β-ocimene (3.25%), andcis-tagetone (1.95%), whereasT. diversifoliaoil is comprised mainly ofα-pinene (63.64%),β-pinene (15.00%), isocaryophyllene (7.62%), nerolidol (3.70%), 1-tridecanol (1.75%), limonene (1.52%), and sabinene (1.00%). The results provide scientific rationale for traditional use of raw products of these plants in controlling livestock ticks by the Bukusu community and lay down some groundwork for exploiting partially refined products such as essential oils of these plants in protecting cattle against infestations withR. appendiculatus.

East Coast Fever

2021 ◽  
pp. 195-220
Author(s):  
Sammy Gichuhi Ndungu ◽  
Sebastian K. Waruri ◽  
James M. Wanjohi
Keyword(s):  
Southern Africa ◽  
East Coast ◽  
Protozoan Parasite ◽  
Rhipicephalus Appendiculatus ◽  
East Coast Fever ◽  
Therapeutic Drugs ◽  
Major Constraint ◽  
Drug Companies ◽  
Ear Tick ◽  
The Cost

East coast fever, a disease of cattle caused by the protozoan parasite Theileria parva and transmitted by the three-host tick Rhipicephalus appendiculatus (the brown ear tick), is a major constraint to cattle production in Eastern, Central, and Southern Africa. In Kenya it is the most important tick-borne disease and a major constraint in cattle productivity. This is due to the high morbidity and mortality it causes in susceptible herds, the cost of control of the vector ticks, and the cost of treatment of clinical cases. Animals that recover from the disease also suffer from reduced productivity which can be long term. The limited distribution of the tick and the disease to only East, Central and Southern Africa also means that the market for therapeutic drugs and acaricides is small. Therefore, drug companies are not keen on funding research and development of new drug and acaricide molecules when resistance occurs.

scholarly journals Wiener Polarity Index Calculation of Square-Free Graphs and Its Implementation to Certain Complex Materials

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Lin Zhang ◽  
Tian-Le Sun ◽  
Micheal Arockiaraj ◽  
M. Arulperumjothi ◽  
S. Prabhu
Keyword(s):  
Quantitative Structure Activity Relationship ◽  
Complex Materials ◽  
Mathematical Technique ◽  
Polarity Index ◽  
Structure Activity ◽  
Physical Chemical ◽  
Chemical Descriptors ◽  
Set Up ◽  
Chemical Materials

Molecular topology is a portion of mathematical chemistry managing the logarithmic portrayal of chemical materials, permitting a tremendous yet straightforward characterization of the compounds. Concerning the traditional physical-chemical descriptors, it is conceivable to set up direct quantitative structure-activity relationship methods to associate with such descriptors termed topological indices. In this study, we have developed the mathematical technique to study the Wiener polarity index of chemical materials without squares. We have taken the cancer treatment drugs such as lenvatinib and cabozantinib to illustrate our approach. In addition, we explored the inherent property of silicate, Sierpiński, and octahedral-related complex materials that the edge set can be decomposed in such a way that any edge in the same part of the decomposition has an equal number of neighboring vertices and applied the technique to derive the formulae for these materials.

The effect of the brown ear-tick Rhipicephalus appendiculatus on the growth of Sanga and European Breed cattle

1988 ◽  
Vol 30 (2) ◽  
pp. 149-164 ◽  
Author(s):  
R.A.I. Norval ◽  
R.W. Sutherst ◽  
J. Kurki ◽  
J.D. Gibson ◽  
J.D. Kerr
Keyword(s):  
Rhipicephalus Appendiculatus ◽  
European Breed ◽  
Ear Tick
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