Available online 31 December 2016
In Press, Accepted Manuscript — Note to users
Research paper
- a Wageningen University & Research, Department of Animal Sciences, Animal Nutrition Group, PO Box 338, 6700 AH, Wageningen, the Netherlands
- b Department of Animal, Rangeland and Wildlife Sciences, Mekelle University, PO Box 231, Mekelle, Ethiopia
- c UMR 1225 IHAP INRA/ENVT, 23 Chemin des Capelles, Toulouse F-31076, France
- d Université de Toulouse, INP-ENVT, 23 Chemin des Capelles, Toulouse F-31076, France
- e Laboratory of Organic Chemistry and Chemical Biology, Department of Chemistry, University of Turku, FI-20014, Turku, Finland
- f Department of Animal Health, Utrecht University, PO Box 80163, 3508 TD, Utrecht, the Netherlands
- Received 12 October 2016, Revised 23 December 2016, Accepted 29 December 2016, Available online 31 December 2016
Highlights
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- The browse plant species exhibit in vitro anthelmintic properties against Haemonchus contortus.
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- Proanthocyanidin concentration is not necessarily related to anthelmintic property.
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- Polyphenols other than tannins exert anthelmintic activity in the browse.
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- In some tannin containing browse, anthelmintic properties are mainly due to non-phenolic compounds.
Abstract
The
aims of the present study were to (a) evaluate the anthelmintic
activity of 10 East African browse extracts, (b) examine their role in
inhibition of Haemonchus contortus larval exsheathment, (c)
establish relationship between inhibition of larval exsheathment and
browse extract polyphenol composition. Acetone/water (70/30%) extracts
of air dried leaves of Acacia etbaica, Cadaba farinosa, Capparis tomentosa, Dichrostachys cinerea, Dodonaea angustifolia, Euclea racemosa, Maerua angolensis, Maytenus senegalensis, Rhus natalensis and Senna singueana were used. The larval exsheathment inhibition assay (LEIA) was applied using H. contortus third stage larvae (L3)
and extract concentrations of 0, 150, 300, 600, 1200 μg/ml phosphate
buffered saline (PBS). Data were analysed using the PROC MIXED procedure
of SAS. Polyvinylpolypyrrolidone (PVPP) was used to evaluate whether
polyphenols were involved in L3 exsheathment inhibition. All browse extracts significantly (P ≤ 0.0001) inhibited larval exsheathment in a dose dependent manner. The dose required to inhibit 50% of the larvae (EC50) was highest in C. farinosa and lowest in E. racemosa and M. senegalensis. Significant differences (P < 0.001) between the control and PVPP treated A. etbaica, C. tomentosa, M. angolensis, R. natalensis and D. cinerea indicates that larval inhibition was largely due to non-phenol compounds. For E. racemosa, M. senegalensis, D. angustifolia and S. singueana,
PVPP treatment reversed inhibition activity and in these extracts,
inhibition was mostly attributable to tannin and other polyphenols
(kaempferol, quercetin and myricetin based aglycones and glycosides).
Overall, browse extracts have anthelmintic property against H. contortus and larval inhibition resulting from the presence of phenolic and non-phenolic compounds.
Keywords
- Proanthocyanidins;
- larvae;
- exsheathment;
- Haemonchus contortus
© 2016 Published by Elsevier B.V.
Accepted manuscripts are Articles in Press
