Table 3 Non-experimental validation of ethnoveterinary remedies used for horses in BC and Trinidad

Arctostaphylos uva-ursi

Leaves contain arbutin which is converted in alkaline urine to hydroquinone (antibacterial and anti-inflammatory action).

20–25

Astragalus membranaceus

Astragalus increases T-cell-mediated immune functions in vitro, in mice, and in uncontrolled trials in humans. Polysaccharide fractions enhance phagocytosis, increase macrophage numbers, and enhance humoral immunity. Astragalus root increases the immune-stimulating effects of interleukin-2 and acyclovir.

26–31

Calendula officinalis

Calendula is anti-inflammatory and promotes epithalization; it is also used for focal skin irritation.

32–34, 28

Cecropia pachystachya

In vivo studies of Cecropia pachystachya showed weak broncodilator activity and cardiovascular toxicity on endovenous administration on dogs and rabbits. Cecropia obtusifolia has shown antihypertensive, diuretic, hypoglycemic, analgesic and central depressor effects. An infusion prepared with the leaves of C. obtusifolia produced beneficial effects on carbohydrate and lipid metabolisms when it was administered to patients with type 2 diabetes.

35–36

Cichorium intybus

Four of six rat stomachs were protected from EtOH damage by aqueous extracts of Cichorium intybus.

37

Cordia curassavica

Cordia curassavica hexane extracts showed antibacterial activity against Gram-positive and Gram-negative bacteria. The crude dichloromethane extract of Cordia curassavica showed significant antiedematogenic activity and antinociceptive activity.

38–39

Crataegus oxycantha

Hawthorn (Crataegus oxycantha) may increase myocardial contractility and reduce peripheral vascular resistance. The Crataegus cohort in one study showed less marked symptoms of heart failure after 2 years (fatigue, stress dyspnoea, palpitations).

40–42

Curcuma longa

In a randomised, double-blind, placebo-controlled, parallel group clinical trial of P54FP, 61 client-owned dogs with osteoarthritis were randomly allocated to receive P54FP (an extract of Curcuma domestica and Curcuma xanthorrhiza) or a placebo orally twice daily for eight weeks. There was a statistically significant treatment effect in favour of P54FP (P = 0.012). The clinical efficacy of a formulation containing roots of Withania somnifera, the stem of Boswellia serrata, rhizomes of Curcuma longa and a zinc-complex (Articulin-F), was evaluated in a randomized, double-blind, placebo controlled, cross-over study in 42 patients with osteoarthritis for three months. Treatment with the herbomineral formulation produced a significant drop in severity of pain (P < 0.001) and disability score (P < 0.05).

43–44

Desmodium adscendens

The butanolic extract of Desmodium adscendens inhibits contraction of the ileum and trachea in guinea pigs. Three active triterpenoid glycosides were found. An extract of Desmodium grahami produced a concentration-dependent inhibition of spontaneous ileum contractions. The extract showed antimicrobial activity against pathogenic enterobacteria supporting its ethnomedical use for gastrointestinal disorders. Three antimicrobial isoflavones were isolated from Desmodium canum.

45–48

Echinacea purpurea

Echinacea purpurea has been investigated for its potential to activate the innate immune response. A time course study, using the time of sheep red blood cells (SRBC) immunization to mimic the onset of illness, examined the effects of 8 and 4 days of Echinacea purpurea treatment at 0.6 mL/kg/day. Only in the 4-day administration, with dosing beginning 1 hour after SRBC immunization, was there an observed enhancement of the antibody forming cell response. This supports the acute use of Echinacea purpurea in traditional medicine, and demonstrates the potential for enhancement of humoral and innate immune responses.

49

Equisetum arvense

Equisetum arvense has demonstrated hypoglycaemic and diuretic activity. The hydroalchoholic extract of stems of Equisetum arvense produced an antinociceptive effect and anti-inflammatory activity linked to beta-sitosterol, campesterol and isofucosterol. A standardized extract from horsetail (Equisetum arvense) was administered to 11 volunteers following a flavonoid-free diet for 8 days. Hippuric acid, the glycine conjugate of benzoic acid, increased twofold after drug intake.

50–51

Euphrasia officinalis

Eyebright (Euphrasia officinalis) has anti-inflammatory activity. Eyebright contains quercetin, a bioflavonoid that may inhibit mast cell degranulation.

52, 28

Filipendula ulmaria

Meadowsweet (Filipendula ulmaria) contains a heparin-like anticoagulant in the flowers. An ointment composed of flowers of Filipendula ulmaria was studied for its efficacy against uterine cervical cancer in 48 patients. Positive responses were recorded in 32 patients (67%), including 25 cases (52%) of complete regression of dysplasia.

53–55, 56

Galium aparine

Asperuloside, an iridoid, is a mild laxative and has anti-inflammatory activity.

56

Glycyrrhiza glabra

This plant has been studied for its synergistic properties and its usefulness for respiratory conditions.

57–60

Harpagophytum procumbens

Chrubasik has conducted large trials with human patients using devil's claw and found that it relieved pain. Harpagophytum procumbens preparation was used to treat ten horses for degeneration of the proximal intertarsal, distal intertarsal and tarsometatarsal joints and found to be equivalent to the phenylbutazone control. Devil's claw has a protective action against arrhythmia.

61–66

Hyssopus officinalis

Antimicrobial activity of hyssop is linked to polysaccharides, essential oil, caffeic acid, tannins, and specifically (-)-cis- and (-)-trans-3-pinanones. Polysaccharides and crude extracts were active against HIV-type 1 and HIV-3 and non-toxic to uninfected cells. Extracts suppress hyperglycemia. The dried plant does not have the toxin pinocamphone.

68–69

Lavandula angustifolia

Extracts, fractions and essential oil of Lavandula angustifolia are reported to have CNS-depressant, anti-convulsive, sedative, anti-bacterial effects. Lavender (Lavendula sp.) has been used as a nocturnal sedative for elderly patients in the form of an air freshener. It has shown benefits in cancer care and stress. The calcium channel blocking activity of the aqueous-methanolic extract of Lavandula stoechas flowers (LS) may be responsible for the folk uses. At a dose of 600 mg/kg of LS, mice were calm and relaxed.

70–72

Lavandula augustifolia

Forty-two patients with advanced cancer were randomly allocated to receive weekly massages with lavender essential oil and an inert carrier oil (aromatherapy group), an inert carrier oil only (massage group) or no intervention (four week courses). Sleep scores improved significantly in both the massage and the combined massage (aromatherapy and massage) groups. There were also statistically significant reductions in depression scores in the massage group.

73

Magnolia grandiflora

A Chinese prescription containing Magnolia bark and ginger rhizome among others, is used to treat mental illnesses. Administration of this decoction and fluoxetine produced beneficial effects on rats subjected to chronic mild stress. Magnolia grandiflora contains magnolol and honokiol which exhibit a central nervous system effect and muscle relaxant activity (Bastidas et al., 1998). An improved elevated plus-maze test in mice revealed the anxiolytic potential of honokiol from Magnolia officinalis and Magnolia obovata.

74–76

Matricaria recutita syn. Matricaria camomilla

Apigenin is the sedative ingredient in chamomile. Aqueous 70% methanol extracts of Chamomilla recutita inhibited the growth of Helicobacter pylori, a Gram-negative bacteria responsible for chronic gastritis, peptic ulceration and gastric cancer. Treatment with Angelica sinensis and Matricaria chamomilla reduced hot flushes in menopausal women.

77–81

Mentha piperita

Peppermint (Mentha piperita) may reduce intestinal spasm and in one study, enhanced gastric emptying. Several studies of the efficacy of peppermint oil on irritable bowel syndrome showed that its activity was linked to the relaxation of intestinal smooth muscle. One study reported that peppermint odour had a positive effect on running speed.

82–85

Momordica charantia

Momordica charantia has many medicinal properties.

86

Mucuna pruriens

The spicular hairs of the pod of Mucuna pruriens penetrate skin causing intense irritation. Hairs contain 5-hydroxytryptamine (serotonin) and the itching produced by the hairs is due to the liberation of histamine in the epidermal layer of the skin.

87–89

Musa paradisiaca

Musa sapientum var. Cavendishii contains soluble and insoluble dietary fibre that contributes to its hypo-cholesterolaemic effect. Other studies found that dried unripe plantain banana (Musa sapientum L. var.paradisiaca) was anti-ulcerogenic. One study found that extracts of both raw Musa sapientum Linn. Musa paradisiacal bananas protected the rat stomach from indomethacin-induced injuries. The extract from Musa sapientum Linn. had a significant healing effect on acetic acid-induced ulcers.

90–93

Nasturtium officinale

Histamine release inhibitors (flavonols and megastigmanes) were found in watercress (Nasturtium officinale). Phenethyl isothiocyanate (PEITC) which is released upon chewing of watercress (Nasturtium officinale) is a chemoprotective agent.

94–97

Nopalea cochenillifera

More studies need to be conducted on this plant. An oral glucose tolerance test showed that stems of Nopalea cochinellifera raises blood glucose levels in mice.

98

Oxalis corniculata

Five Oxalis species including Oxalis corniculata have been used to treat skin infections and unspecified microbial infections. Dichloromethane extracts of Oxalis erythrorhiza showed activity against methicillin-resistant and methicillin-sensitive strains of Staphylococcus aureus as well as towards five dermatophytes. Embelin also inhibits the five dermatophytes.

99

Passiflora incarnata

In one non-randomized clinical observatory trial a combination product composed of valerian root and passion flower extracts was evaluated using 20 ambulatory patients (Dhawan et al., 2004). The plant combination reduced occipital region central hyperactivity after 2 weeks. The anxiety and depression self rating decreased for all patients. Many other studies, and adverse reactions, are summarised in this paper.

100

Petroselinum crispum

Parsley's diuretic effect was validated in rat experiments. Six rats offered an aqueous parsley seed extract to drink, eliminated a significantly larger volume of urine per 24 h (P < 0.001) as compared to when they were drinking water, but less than that observed with known diuretics amiloride and furosemide. The rats served as their own controls.

101

Pimenta racemosa

Antinociceptive and anti-inflammatory effect activity was found in the leaves of Pimenta racemosa.

102

Plantago major

Plantago major contains several compounds that aid in wound healing. The polysaccharide fraction from P. major protects against pneumococcal infection in mice when administered systemically, with prechallenge by stimulation of the innate immune system.

103–105

Pulmonaria officinalis

The anti-coagulant glycopeptide from Pulmonaria officinalis reduces the death rate of animals with exogenous thromboplastmenia. T-100 anticoagulants were isolated from the ammonia extract of Pulmonaria mollissima. The anticoagulants consist of a peptide and a glycopeptide which in nontoxic doses causes stable hypocoagulemia in animals.

106–107

Prunella vulgaris

The polysaccharide prunelline has immunomodulation effects and some constituents have antioxidative, anti-inflammatory, and moderate activity on Gram positive bacteria. Other polysaccharides have antiviral activity. The aqueous fraction of the plant inhibits anaphylactic shock, allergic reactions, protects rat erythrocytes against haemolysis and kidney and brain homogenates against lipid peroxidation.

108–109

Psidium guajava

Leaf extracts of Psidium guajava act as antidiarrhoeic agents by a triple pronounced antibacterial, antiamoebic and antispasmodic action (inhibition of intestinal motility).

111–113

Ricinus communis

The wounded leaf of Ricinus communis contained increased free fatty acids and diacylglycerol and decreased in phospholipids. Leaves of Ricinus communis are nematicidal.

114–115

Salix spp.

A standardized willow bark extract was examined in 127 outpatients with osteoarthritis and rheumatoid arthritis in 2 randomized, controlled, double-blind trials with follow up for 6 weeks. No statistical differences were found. Ethanolic Salix extract 1520L inhibits COX-2-mediated PGE2 release through compounds that were not salicin or salicylate. In a 4-week blinded trial, 210 patients with an exacerbation of chronic low back pain were randomly assigned to receive an oral willow bark extract with either 120 mg (low dose) or 240 mg (high dose) of salicin, or placebo, with tramadol as the sole rescue medication. The numbers of pain-free patients in the last week of treatment were 27 (39%) of 65 in the group receiving high-dose extract, 15 (21%) of 67 in the group receiving low-dose extract, and 4 (6%) of 59 in the placebo group (P <0.001). Significantly more patients in the placebo group required tramadol (P <0.001) for each week of the study.

116–117

Salvia officinalis

Salvia officinalis is reported to have anti-bacterial, fungistatic, virustatic, astringent, eupeptic, hypotensive, anti-spasmodic, central nervous system-depressant actions, anti-inflammatory and anti-hydrotic effects. Its water and alcohol extracts have anti-viral activity. The chloroform extracts of Salvia officinalis leaves, and the active compound ursolic acid, showed anti-inflammatory properties after topical application.

118

Scrophularia nodosa

Phenolic fractions of aerial parts of Scrophularia frutescens and sambucifolia showed potent antibacterial activity. Saikosaponins from Scrophularia scorodonia had in vivo anti-inflammatory effects.

119–120

Silybum marianum

Several studies have been found that milk thistle (Silybum marianum) has liver protectant properties.

121–122

Stachys officinalis

The hydroalcoholic extract of Stachys lavandulifolia showed anxiolytic effects with lower sedative activity than diazepam. Aqueous 70% methanol extracts of Stachys alopecuros inhibited the growth of Helicobacter pylori.

123–126

Stachytarpheta jamaicensis

After intraperitoneal administration of gradual aqueous doses obtained from Stachytarpheta jamaicensis leaves in rats the following effects were seen: a reduction of motor activity and the alarm reaction, ataxia, sedation, analgesia, anesthesia, ptosis, piloerection, head tremors and a significant reduction of body temperature followed by apnea and the death of the animals. Iridoid ipolamiide and the phenylpropanoid glycoside, verbascoside, were found. The crude protein level of Stachytarpheta jamaicensis is fairly high.

127–129

Tanacetum parthenium

Feverfew (Tanacetum parthenium) has antinociceptive and anti-inflammatory effects attributed to the parthenolide content in the leaves and flowers.

130–131

Taraxacum officinale

Teas composed of common dandelion root and aerial parts are licensed in Germany for the treatment of biliary disorders, digestive and gastrointestinal complaints, and to provoke diuresis.

131, 28

Ulmus fulva

Slippery elm (Ulmus fulva) is effective on its own as a demulcent in dogs with mild stomach ulcers.

28

Verbascum thapsus

Mullein (Verbascum thapsus) leaves and flowers have expectorant and demulcent properties (from mucilagionous constituents) which are used to treat respiratory problems such as bronchitis, dry coughs, whooping cough, tuberculosis, asthma, and hoarseness. Mullein is mildly diuretic and has a soothing and anti-inflammatory effect on the urinary tract, and acts as a mild sedative. Leaf extracts of Verbascum thapsus have shown antiviral, antibacterial and antifungal activity.

132–134

Viburnum opulus

Water-soluble polysaccharide fractions were isolated from the squeezed berries of Viburnum opulus. Some plant polysaccharides have immunostimulating activity: they enhance phagocytosis.

135–136

Vitex agnus-castus

Animal experiments have shown evidence of a dopaminergic effect of Vitex agnus-castus.

137–139