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Vitex agnus-castus

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Vitex agnus-castus
General form of a blossoming adult Vitex agnus-castus
Scientific classification
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V. agnus-castus
Binomial name
Vitex agnus-castus

Vitex agnus-castus, also called vitex, chaste tree, chasteberry, Abraham's balm,[1] lilac chastetree,[2] or monk's pepper, is a native of the Mediterranean region. It is one of the few temperate-zone species of Vitex, which is on the whole a genus of tropical and sub-tropical flowering plants.[3] Theophrastus mentioned the shrub several times, as agnos (άγνος) in Enquiry into Plants.[4] It has been long believed to be an anaphrodisiac but its effectiveness remains controversial. This is a cross-pollinating plant. However self-pollination may also occur now and then.[5]

Etymology

Vitex, its name in Pliny the Elder, is derived from the Latin vieo, meaning to weave or to tie up, a reference to the use of Vitex agnus-castus in basketry.[6] Its macaronic specific name repeats "chaste" in both Greek and Latin, and considered to be sacred to the goddess Hestia/Vesta.

Confusion with Vitex on the part of early settlers in the West Indies may have given to Ricinus communis the name "Castor-oil plant".[7] Or the name "castor oil" might have come from its use as a replacement for castoreum.[8]

Agronomy

The controlled cultivation of medicinal plants like vitex agnus-castus gains increasing importance due to the modern quality standards and safety regulations such as GMP, that are required practices in order to conform to the guidelines recommended by agencies that control authorization and licensing for manufacture and sale of inter alia drug products, and GACP (Good Agricultural And Collection Practice), that is a guideline to ensure appropriate and consistent quality of medicinal plant respectively herbal substances.[9][10] Only one variety of monks pepper, namely the variety “Agnuzell 440” that is optimized for medicinal use, is registered (as of April 2009) with CPVO, a system of plant variety rights.[11] But the controlled cultivation is economically not satisfactory regarding the yield.[9]

Reproduction

This plant could also be reproduced vegetatively. One possibility is to use 5–8 cm long piece of the ripening wood with buds in July or August and another is to cut the ripe wood in November and then let it root in a cold box.[5] Also in vitro reproduction with spike of the shoots or node explants is possible.[12]

Cultivation

Vitex agnus-castus is widely cultivated in warm temperate and subtropical regions for its delicate-textured aromatic foliage and butterfly attracting[13] spikes of lavender flowers in late summer in cooler climates. It grows to a height of 1–5 meters. It requires full sun or partial shade along with well-drained soil. Under ideal conditions it is hardy to -10 degrees F USDA Zone 6, and can be found on the south shore of Long Island and Nantucket on the East Coast of North America and in the southwest of England.[14]

This plant is inter alia a brackish water habitant. Consequently, it is salt tolerant to a certain level. Cold and wet weather results to high yield loss of Monks pepper. The plant grows well on loamy neutral to alkaline soil.[5] The monks pepper fruits from one single tree can be harvested for more than 15 years. This indicate that the monks pepper can’t be integrated in a usual crop rotation system.[5][15] Though, it is suggested to have legumes as its previous crop for nitrogen supply for the monks pepper in young stage. Besides, it is suggested to sow dissimilar plants such as monocots as its subsequent crop so that it might be easier to control the monks pepper plant, the dicot. Because the fruits of monks pepper tend to fall constantly and uncontrollably, it is likely that the plant can grow as weed again.[5]

It is said that at a row spacing of 180 cm the overall best yield per hectare can be achieved if the plant spacing is around 70 cm.[5]

Pinching out the tips of branches has no significant influence on growth, branching and number of shoots. Pruning back the branches in autumn has a positive influence on fruit yield while a re-pruning in spring can induce an increase of vegetative shoot and thus to tremendous fruit yield loss.[5]

Harvest

The flowering and ripening process is not simultaneously. At the other hand it enables to get fresh fruits respectively seeds over a long span of time. Additionally, the ripe fruit tend to fall down unpredictably and may get lost. Thus, there is no optimal fixed harvest time. Consequently, to avoid yield loss unripe fruits need to be harvested. This too early harvesting has no effect on quality.[5] Overall it is said that harvesting the fruits by hand is the most convenient solution.[15]

Diseases and pests

Thysanoptera or widely known as Thrips can cause great damage to the growth and the generative development of Vitex agnus castus.[16] The insect feeds on Chastetree by sucking up the contents or puncturing them. As well Chastetree is the only known host (especially in Israel) for the bug insect called Hyalesthus obsoletus. This cicada is the vector for Black wood disease of grapevines. Hyalesthus obsoletus prefers V. agnus castus more as a host than the grapevine. In this case Chastetree can be used as a biological control agent by planting it around vineyards to trap the Hyalesthus obsoletus. [17] V. agnus-castus was found not only to be an appropriate food source for the adult vectors, but also a reservoir of Candidatus Phytoplasma solani (bacterial Phytoplasma species), the casual agent of the Black wood disease in grapevines.[18] The pathogen-caused leaf spot disease can almost defoliate V. agnus castus. Furthermore root rot can occur, when soils are kept too moist.[19]

Chemical compounds

Flavonoids (vitexin, casticin), iridoid glycoside (agnuside, aucubin),[20] p-hydroxybenzoic acid,[21] alkaloids, essential oils, fatty oils, diterpenoids and steroidal hormone precursors have been identified in the chemical analysis of Vitex agnus-castus.[22] They occur in the fruits and in the leaves.[20]

Essential oils

Essential oils have been found in the fruits and in the leaves. The oil of leaves, unripe and ripe fruits differ in compounds. 50 compounds were identified in the oil of unripe fruits, 51 compounds in the oil of ripe fruits and 46 compounds in the oil of the leaves. 1,8-cineole and sabinene are the main monoterpene components and beta-caryophyllene is the major sesquiterpene compound found in the fruits of Vitex agnus-castus.[23] Other important chemical compounds are: limonene, alpha- and beta-pinene, trans-beta-farnesene.[20] There are some slight differences between fruits from white flowering plants and such from violet flowering ones. The oil of fruits of white flowering plants have a higher amount of monoterpene constituents. The content of mono- and sesquiterpene was nearly the same for both oils.[23] The leaves mainly contain 1,8-cineole, trans-beta-farnesene, alpha-pinene, trans-beta-caryophyllene and terpine-4-ol. All essential oils found in Vitex agnus-castus have an antimicrobial effect. Antifungal effects are slightly higher compared to antibacterial effects. Antibacterial activity is higher in oils coming from white flowering plants than from such of violet flowering plants.[20][23][24]

Drugs

Agni casti fructus (ripe, dried fruits) is a pharmaceutical drug made out of Vitex agnus-castus. Albania and Morocco are the main export countries. The fruits are wildly collected (wild grafting). There are three other types of drugs of Vitex agnus-castus fruits: Vitex agnus-castus hom. HAB1 (ripe, dried fruits), Agnus castus hom PFX (dried fruits) and Agnus castus hom. HPUS88 (fruits). The smell of ground fruits is aromatic, sage-like whereas the taste is spicy, pepper-like. The drug Vitex agnus-castus hom. HAB1 is a round, up to 5 mm big, red-brown to dark fruit. In the middle it is often yellow. It contains 4 fruit compartments with one seed per compartment. A minimum of 0.4% of essential oil is required. Viticis folium (dried leaves) is another drug which is produced from Vitex agnus-castus. The whole drug consists of lanceolate leaves with tomentose under and hairless upper sides.[20]

Herbal uses

Vitex, also a traditional plant in Africa, is a little-known fruit plant that has potential to improve nutrition, boost food security, foster rural development and support sustainable landcare.[25]

The leaves and tender stem growth of the upper 10 cm (3.9 in), along with the flowers and ripening seeds, are harvested for alternative medicinal purposes. The berries are harvested by gently rubbing the berries loose from the stem. The leaves, flowers, and/or berries may be consumed as a decoction, traditional tincture, cider vinegar tincture, syrup, elixir, or simply eaten straight off the plant as an alternative medicinal food.[26] A popular way of taking Vitex is on awakening as a simple 1:1 fluid extract, which is said to interact with hormonal circadian rhythms most effectively.[27]

In alternative medicine, it is believed the berries are a tonic herb for both the male and female reproductive systems. The leaves are believed to have the same effect but to a lesser degree.[26][27]

In ancient times it was believed to be an anaphrodisiac, hence the name chaste tree. Pliny, in his Historia Naturalis, reports the use of stems and leaves of this plant by women as bedding "to cool the heat of lust" during the time of the Thesmophoria, when Athenian women left their husbands' beds to remain ritually chaste. At the end of the thirteenth century John Trevisa reports of it "the herbe agnus-castus is always grene, and the flowre therof is namly callyd Agnus Castus, for wyth smel and vse it maketh men chaste as a lombe".[28] Chaucer, in "The Flower and the Leaf," refers to it as an attribute of the chaste Diana, and in the 16th century the English herbalist William Turner reports the same anaphrodisiac properties of the seed, both fried and not fried. More recently, this plant has been called monk's pepper in the thought that it was used as anti-libido medicine by monks to aid their attempts to remain chaste. There are disputed accounts regarding its actual action on libido, with some claims that it is anaphrodisiac and others that it is aphrodisiac. Because of the complex mechanism of action it can be probably both, depending on concentration of the extract and physiologic variables (see below).

According to the Mayo Clinic’s ‘Book of Alternative Medicine’, 2010, second edition, ch.3 pg. 51: under ‘Chasteberry’ it says: “There’s no evidence it reduces sexual desire.”

Medical use

Close up of vitex-agnus-castus-flowers with carpenter bee (Xylocopa sp.)

Clinical studies have demonstrated effectivness of standardised and controlled medications produced from extract of the plant in the management of premenstrual stress syndrome (PMS),[29][30][31] and cyclical breast pain (mastalgia).[32] The medication is recommended in Germany.[33][34]

Mechanism of action

It is believed that some of the compounds found in the plant work on the pituitary gland which would explain its effects on hormonal levels. A study has shown that extracts of the fruit of VAC can bind to opiate receptors; this could explain why intake of VAC reduces PMS discomforts.[35]

The mechanism of action is not fully understood[36] but it is assumed that it has dopaminergic effects resulting in changes of prolactin secretion. At low doses, such as might have been used in previous centuries for suppression of sexual desire, it inhibits activation of dopamine 2 receptor by competitive binding, causing a slight increase in release of prolactin. In higher concentrations, as in modern extracts, the binding activity is sufficient to reduce the release of prolactin. A study has found that treatment of 20 healthy men with higher doses of Vitex agnus-castus was associated with a slight reduction of prolactin levels, whereas lower doses caused a slight increase as compared to doses of placebo.[37] A decrease of prolactin will influence levels of Follicle-stimulating hormone (FSH) and estrogen in women ;[citation needed] and testosterone in men .[citation needed] Dopaminergic compounds (diterpenes with prolactin-suppressive effects that were almost identical in their prolactin-suppressive properties to dopamine itself) present in Vitex agnus castus seem likely to be the clinically important compounds which improve premenstrual mastodynia and possibly also psycho-somatic symptoms of PMS.[38]

Current uses

Vitex agnus-castus is used to alleviate symptoms of various gynecological problems. All evidence is limited to standardised controlled extracts such as used in Germany, different extracts or herbal mixes may have significantly different properties and safety issues. Some of the modern uses include premenstrual syndrome, abnormal uterine bleeding disorders and mastodynia.

Good evidence and safety exists for these uses:[33]

No specific clinical studies but use partially supported by clinical evidence on symptoms and mechanism of action:

Emerging uses (with very early evidence):

Contraindications

It is recommended that Vitex agnus-castus be avoided during pregnancy due to the possibility of complications.[33][46]

Other uses

Historical uses, uses outside the scope of medicine.

  • Galactagogue, historical usage in very low concentrations and not advisable today.[47] However one recent study did find "Oral administration of 70 mg/kg/day of Vitex agnus-castus extract in lactation stages, significantly increased serum prolactin, compared with the control group of rats."[48]
  • Potential use as an insect repellent[49]
  • Used in supplements for male bodybuilders as a secondary component because of its effects on testosterone levels.[22]

References

  1. ^ New English Dictionary, s.v. "Chaste-tree".
  2. ^ NRCS. "Vitex agnus-castus". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 6 August 2015.
  3. ^ David J. Mabberley. 2008. Mabberley's Plant-Book third edition (2008). Cambridge University Press: UK.
  4. ^ Pliny reports that some Greeks called it lygos, others agnos.
  5. ^ a b c d e f g h Verein für Arznei- und Gewürzpflanzen Saluplanta. 2013. Handbuch des Arznei- und Gewürzpflanzenbaus volume 5 Arznei- und Gewürzpflanzen L-Z, pages 192-199. Verein für Arznei- und Gewürzpflanzen Saluplanta: Bernburg, Germany. ISBN 978-3-935971-64-5 (set).
  6. ^ Umberto Quattrocchi. 2000. CRC World Dictionary of Plant Names volume I, page 91. CRC Press: Boca Raton; New York; Washington,DC;, USA. London, UK. ISBN 978-0-8493-2673-8 (set).
  7. ^ Coats (1964) 1992.
  8. ^ http://www.billcasselman.com/cwod_archive/beaver_castor_two.htm
  9. ^ a b Chaanin A. 2014. "Der kontrollierte Anbau von Vitex agnus-fascastus–Chancen und Risiken". Julius-Kühn-Archiv. 446: 16. doi:10.5073/jka.2014.446.004.{{cite journal}}: CS1 maint: numeric names: authors list (link)
  10. ^ "GACP-Guideline" (PDF; 44 kB). EMEA. 2006.
  11. ^ Verein für Arznei- und Gewürzpflanzen Saluplanta. 2009. Handbuch des Arznei- und Gewürzpflanzenbaus volume 1 Grundlagen des Arznei- und Gewürzpflanzenbaus I page 617. Verein für Arznei- und Gewürzpflanzen Saluplanta: Bernburg, Germany. ISBN 978-3-935971-54-6 (set).
  12. ^ Balaraju K. Agastian P. Preetamraj J.P. Arokiyaraj S. Kade P. Ignacimuthu S. 2008. "Micropropagation of Vitex agnus-castus, (Verbenaceae)—a valuable medicinal plant". In Vitro Cellular & Developmental Biology - Plant. 44: 436–441. doi:10.1007/s11627-008-9155-9.{{cite journal}}: CS1 maint: numeric names: authors list (link)
  13. ^ Soule, J.A. 2012. Butterfly Gardening in Southern Arizona. Tierra del Soule Press, Tucson, AZ
  14. ^ United States Department of Agriculture. "Vitex Agnus-Castus Profile". Retrieved 15 July 2012.
  15. ^ a b van Rensen I. 2010. "Mönchspfeffer". Z Phytother. 31 (6): 322–326. doi:10.1055/s-0030-1262410.{{cite journal}}: CS1 maint: numeric names: authors list (link)
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  17. ^ Sharon R. Soroker V. Wesley SD. Zahavi T. Harari A. 2005. Weintraub PG. Vitex agnus-castus is a preffered host plant for hyalesthes obsoletus. Journal of Chemical Ecology. 31:1051-1063
  18. ^ Kosovac A. Radonji S. Hrnci S. Krstic O. Tosevski I. Jovic J. 2016. Molecular tracing of the transmission routes of bois noir in Mediterranean vineyards of Montenegro and experimental evidence for the epidemiological role of Vitex agnus-castus (Lamiaceae) and associated Hyalesthes obsoletus (Cixiidae). Plant Pathology. 65: 285–298
  19. ^ Gilman E. and Watson D. 1994. Vitex agnus-castus ‘Alba’; ‘Alba’ Chastetree Fact Sheet ST-665. A series of the Environmental Horticulture Department. Florida Cooperative Extension Service. Institute of Food and Agricultural Sciences. University of Florida
  20. ^ a b c d e Hager H.; et al. (2013). Hänsel R.; et al. (eds.). Hagers Handbuch der Pharmazeutischen Praxis: Drogen P-Z Folgeband 2. Springer-Verlag. pp. 1183–1196. ISBN 978-3-642-57881-6. {{cite book}}: Explicit use of et al. in: |editor1-last= (help); Explicit use of et al. in: |last1= (help)
  21. ^ Hoberg, Eva; Meier, Beat; Sticher, Otto (2000). "An analytical high performance liquid chromatographic method for the determination of agnuside and p-hydroxybenzoic acid contents in Agni-casti fructus". Phytochemical Analysis. 11 (5): 327–329. doi:10.1002/1099-1565(200009/10)11:5<327::AID-PCA523>3.0.CO;2-0.
  22. ^ a b Hajdú, Zsuzsanna; Judit Hohmann; Peter Forgo; Tamás Martinek; Máté Dervarics; István Zupkó; György Falkay; Daniel Cossuta; Imre Máthé. "Diterpenoids and flavonoids from the fruits of Vitex agnus-castus and antioxidant activity of the fruit extracts and their constituents". Wiley InterScience. Retrieved 2007-11-11.
  23. ^ a b c Senatore F. Napolitano F. Ozcan Dung M. (2003). "Chemical composition and antibacterial activity of essential oil from fruits of Vitex agnus-castus L. (Verbenaceae) growing in Turkey". Journal of Essential Oil Bearing Plants. 6:3: 185–190.
  24. ^ Stojkovic D. Sokovic M. Glamoclija J. Dzamic A. Ristic M. Grubisic D. (2011). "Chemical composition of antimicrobial activity of Vitex agnus-castus L. fruits and leaves essential oils". Food Chemistry. 128: 1017–1022.
  25. ^ National Research Council (2008-01-25). "Chocolate Berries". Lost Crops of Africa: Volume III: Fruits. Lost Crops of Africa. Vol. 3. National Academies Press. ISBN 978-0-309-10596-5. Retrieved 2008-07-17. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
  26. ^ a b Hartung, T., 2000. Growing 101 Herbs That Heal. Storey Books. ISBN 1-58017-215-6
  27. ^ a b Chevallier, A., 2000. Encyclopedia of Herbal Medicine. Dorling Kindersley. ISBN 0-7894-6783-6
  28. ^ Trevisa, quoted in The New English Dictionary; the misconnection of agnus, for agnos with agnus "lamb" is misleading: "it has nothing to do with the Latin agnus, a lamb," Alice M. Coats notes (Coats, Garden Shrubs and Their Histories [1964] 1992, s.v. "Vitex").
  29. ^ a b Wuttke, W; Jarry H; Christoffel V; Spengler B; Seidlová-Wuttke D. (May 2003). "Chaste tree (Vitex agnus-castus)--pharmacology and clinical indications". Exp Clin Endocrinol Diabetes. 10 (4): 348–57. doi:10.1078/094471103322004866. PMID 12809367.
  30. ^ a b Schellenberg, R. (20 January 2001). "Treatment for the premenstrual syndrome with agnus castus fruit extract: prospective, randomised, placebo controlled study". British Medical Journal. 322 (7279): 134–7. doi:10.1136/bmj.322.7279.134. PMC 26589. PMID 11159568.
  31. ^ a b Berger, D; Schaffner W; Schrader E; Meier B; Brattström A (November 2000). "Efficacy of Vitex agnus castus L. extract Ze 440 in patients with pre-menstrual syndrome (PMS)". Arch Gynecol Obstet. 264 (3): 150–3. doi:10.1007/s004040000123. PMID 11129515.
  32. ^ a b Carmichael, A. R. (2008). "Can Vitex Agnus Castus be Used for the Treatment of Mastalgia? What is the Current Evidence?". Evidence-based complementary and alternative medicine : eCAM. 5 (3): 247–250. doi:10.1093/ecam/nem074. PMC 2529385. PMID 18830450.
  33. ^ a b c Daniele, C. (2005). "Vitex agnus castus: a systematic review of adverse events". Drug Safety. 28 (4): 319–32. doi:10.2165/00002018-200528040-00004. PMID 15783241. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  34. ^ Axel Valet; Kay Goerke; Joachim Steller (2003). Klinikleitfaden Gynäkologie Geburtshilfe. Untersuchung. Diagnostik. Therapie. Notfall. Urban & Fischer. ISBN 3-437-22211-2.
  35. ^ Webster, D.E. (2006). "Activation of the μ-opiate receptor by Vitex agnus-castus methanol extracts: Implication for its use in PMS". Journal of Ethnopharmacology. 106 (2): 216–221. doi:10.1016/j.jep.2005.12.025. PMID 16439081. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  36. ^ "Opioidergic mechanisms underlying the actions of Vitex agnus-castus L.", Biochemical Pharmacology. 2011 Jan 1;81(1):170-7 Authors: Webster DE, He Y, Chen SN, Pauli GF, Farnsworth NR, Wang ZJ
  37. ^ Merz, PG; Gorkow C; Schrödter A; Rietbrock S; Sieder C; Loew D; Dericks-Tan JS; Taubert HD (1996). "The effects of a special Agnus castus extract (BP1095E1) on prolactin secretion in healthy male subjects". Exp Clin Endocrinol Diabetes. 04 (6): 447–53. doi:10.1055/s-0029-1211483. PMID 9021345.
  38. ^ Wuttke, W; et al. (May 2003). "Chaste tree (Vitex agnus-castus)--pharmacology and clinical indications". Phytomedicine. 10 (4): 348–57. doi:10.1078/094471103322004866. PMID 12809367.
  39. ^ a b Cunningham, J.; Yonkers, K. A.; O'Brien, S.; Eriksson, E. (2009). "Update on Research and Treatment of Premenstrual Dysphoric Disorder". Harvard Review of Psychiatry. 17 (2): 120–137. doi:10.1080/10673220902891836. PMC 3098121. PMID 19373620.
  40. ^ Kilicdag, E.; Tarim, E.; Bagis, T.; Erkanli, S.; Aslan, E.; Ozsahin, K.; Kuscu, E. (2004). "Fructus agni casti and bromocriptine for treatment of hyperprolactinemia and mastalgia". International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics. 85 (3): 292–293. doi:10.1016/j.ijgo.2004.01.001. PMID 15145274.
  41. ^ Weisskopf, M.; Schaffner, W.; Jundt, G.; Sulser, T.; Wyler, S.; Tullberg-Reinert, H. (2005). "A Vitex agnus-castus extract inhibits cell growth and induces apoptosis in prostate epithelial cell lines". Planta Medica. 71 (10): 910–916. doi:10.1055/s-2005-871235.
  42. ^ Adelson, K.B.; Loprinzi, C.L.; Hershman, D.L. (2005). "Treatment of hot flushes in breast and prostate cancer". Expert Opinion on Pharmacotherapy. 6 (7): 1095–1106. doi:10.1517/14656566.6.7.1095.
  43. ^ Ambrosius, F (2006). "New indication for Vitex agnus-castus extract?". Zeitschrift für Phytotherapie. 27 (2): 95.
  44. ^ Goetz, P (2009). "Phytotherapy of benign prostatic hyperplasia". Phytotherapie. 7 (5): 275–278.
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  48. ^ Azadbakht, M.; Baheddini, A.; Shorideh, S.M.; Naserzadeh, A. (2005). "Effect of Vitex agnus - Castus L. leaf and fruit flavonoidal extracts on serum prolactin concentration". Journal of Medicinal Plants. 4 (16): 56–61.
  49. ^ Mehlhorn, H.; Schmahl,-G; Schmidt,-J (2005). "Extract of the seeds of the plant Vitex agnus castus proven to be highly efficacious as a repellent against ticks, fleas, mosquitoes and biting flies". Parasitol-Res. 95 (5): 363–5. doi:10.1007/s00436-004-1297-z. PMID 15682335.