Swiss ethnoveterinary knowledge on medicinal plants – a within-country comparison of Italian speaking regions with north-western German speaking regions

Ethnoveterinary research, defined by McCorkle as the “systematic investigation and application of veterinary folk knowledge, theory and practise” [1], is of raising importance in Europe [2, 3] even though conducted mostly in developing countries [3]. Traditional knowledge of medicinal plant use in animals has been recorded from 12 out of 37 European Union and affiliated countries, with Italy, Spain and Turkey being the most intensively investigated ones [2].

Homemade herbal remedies, handed down over generations, may be a useful therapeutic alternative for treatment of livestock [4, 5]. In addition, dissemination of such knowledge may raise awareness of the potential of veterinary phytotherapy [6]. While in developing countries animal health care is often based on self-made preparations, particularly when access to western veterinary products is difficult or too expensive [7], European farmers may opt for such “phytotherapeutic products” in order to comply with EU directives for organic livestock treatment [8]. Moreover, a considerable amount of veterinary antimicrobials is sold in EU each year (4,802 tonnes of active ingredient in 2012) [9] and since the most of this amount is directed to treat livestock species, cross contamination of resistant strains of zoonosis pathogens is more than a possibility [4, 9, 10]. Thus ethnoveterinary medicine may play an important role also in Europe [2].

Switzerland is one of several states which arouse out of the dissolution of the Holy Roman Empire, but differs profoundly in its cultural origins from other European countries. While other states often originated from the consolidation of princely houses domains, the core of Switzerland was born as voluntary union of small communities in a loose federation [11]. The Swiss Confederation expanded over centuries from a central German speaking core to 26 cantons of today. Cantons are relatively autonomous, and the sometimes significant cultural differences are the result of distinctly differing historical paths followed by individual cantons, and are reflected by four linguistic regions and official languages (German, French, Italian and Romansch) [11, 12]. While the topography of Switzerland was largely responsible for the development of cultural and linguistic regions, the political system of a federal republic established in the 19^th century was the basis for a preservation of cultural and linguistic plurality [12].

A comparison of ethnoveterinary data from Spain, Italy and Albania with those from the Romanian region of Transylvania shows only few overlaps [13]. On the other hand, the compared regions are distant from each other and belong to different linguistic regions. But even within the same country and linguistic region significant regional differences have been reported, as e.g. for four territories of the Catalan linguistic area of Spain [14]. In contrast, the comparison of ethnoveterinary data even from two continents (central and southern Italy, Europe, with Tunisia, Africa) shows that about one third of the plant species described for Tunisia are also used in Italy for veterinary purposes [15]. However, a comparative study of ethnoveterinary knowledge of two maximally different regions (regarding history, geography, farm size, farm structure and spoken language) within the same country, and with ethnoveterinary data from the same linguistic region in an neighbouring country has not been conducted up to now in central Europe. Switzerland seems to be predestined to address this question in an exemplary manner due to its large cultural, agricultural, geographical and linguistic diversity on the one hand, and the long history of territorial and political cohesion on the other.

The study area included two different regions of Switzerland: on the one hand, a climatically mild, low altitude area extending over five German speaking cantons (GeC) of central and north-western Switzerland (Solothurn, Basel Landschaft, Basel Stadt, the northern part of Lucerne, and the north-eastern German speaking part of Berne), and a southern, mainly mountainous area comprising the canton of Ticino and adjacent Italian speaking regions (ItR) in the canton of Grisons (Moesa district, Bernina district and Bregaglia municipality) (Fig. 1). Three major biogeographic regions can be distinguished in Switzerland, (i) the Jura, a low mountain range, (ii) the Central Plateau, an alluvial basin and, (iii) the Alps, a high mountain region. GeC represents mainly the Central Plateau, while ItR is part of the Alps. The Alps, in particular, are an area of high plant diversity.

Historically, GeC includes territories of the Old Federation, an association of confederates signing pacts of eternal alliance as early as 1332 (Lucerne), 1353 (Berne), 1481 (Solothurn) and 1501 (Basel), respectively [11]. The canton of Grisons became loosely associated with the Federation in 1498 [11], while the territories of Ticino belonged to the dukes of Milan until 1512, when they were conquered and by this way fell under “foreign” administration of the Federates. Grisons and Ticino became formally part of the Swiss Confederation in 1803 [12].

The area of the GeC is located between 46°96′–47°59′ North and 7°02′–8°51′ East in the north-western part of Switzerland, while ItR is located between 45°81′–46°63′ North and 8°38′–10°16′ East on the southern side of the Swiss Alps. The altitude of GeC is between 246 m and 1,592 m above sea level, with an average annual temperature of 9 °C and annual average precipitation of 1009 mm [16]. The altitude of the ItR is between 194 m and 3,402 m above sea level. Climate in ItR differs widely depending on altitude, with an average annual temperature in between 11,7° and −6 °C [16]. The average annual precipitation ranges between 789 and 2262 mm [16]. Both regions cover approximately 3,900 km². ItR has about 360,000, GeC about 1,090,000 inhabitants [17].

In ItR, out of a total of 790 farms in Ticino, 122 are registered as organic (16%), while the canton of Grisons has the highest percentage of organic farms (55%; 1280 organic farms out of a total of 2298) in Switzerland. About 290 of all farms of Grisons are located in ItR. Due to the mountainous topography of the area, most often reared livestock species are cattle and small ruminants. Also due to missing arable land as base for own crop-feed production poultry is most commonly kept in small herds for self-supply, while pigs have almost no importance [17, 18].

GeC include more densely populated areas, and farms are generally larger and have significantly more cropland. Out of a total of 28,441 farms in the 4 cantons, the area where interviews were carried out counts approximately 10,000 farms. In Bern 212 (5%) of 4,046, in Luzern 234 (7%) of 3,507, in Solothurn 124 (8%) of 1,508, and in both Basel cantons 128 (13%) of 978 were organic farms. The most often reared livestock species were cattle. Small ruminants are negligible, while poultry and pigs have a high importance in the rural economy [17, 18].

Ethnobotany, the “study of the relationship between human beings and vegetation in their environment” [19] is “an interdisciplinary approach, including anthropology, archaeology, botany, chemistry, ecology, pharmacology and psychology (that) leads us to understand the relationship between plants and human societies” [20]. Ethnoveterinary studies have shown differences and similarities between and even within countries [14, 21]. However, a comparison of two maximally different areas within the same country has not been conducted so far. Regarding history, spoken language, geography, farm size and farm structure ItR and GeC represent probably the highest difference within Switzerland. Due to the fact that ItR and Italy belong to the same linguistic area we expected here a close similarity.

The aims of our study were (a) to compare the ethnoveterinary practices of two cultural and sociodemographic different regions of Switzerland, ItR and GeC, (b) to analyse to what extent the ethnoveterinary practices in both regions were in accord with earlier studies conducted in neighbouring areas of Switzerland [22, 23] and Italy [24‐28] and, (c) to estimate if and how far political borders, language and other reasons could be responsible for regional differences in European ethnoveterinary medicine.

Out of the 125 ItR-HSHR, plants belonging to the Asteraceae family were the most frequently mentioned, with a total of 33 HSHR (26%), followed by Linaceae and Urticaceae (13 ItR-HSHR each, 10%). Calendula officinalis L. (15 ItR-HSHR, 12%), Linum usitatissimum L.(13 ItR-HSHR, 10%) and Coffea spp. (9 ItR-HSHR, 7%) were the species with the highest number of reports, while Arnica montana L., Urtica urens L. and Malva neglecta Wallr. were each single ingredient of 7 ItR-HSHR (6%) (Table 1).

Considering the 145 GeC-HSHR, the Asteraceae family was represented in 36 (25%) GeC-HSHR. Rubiaceae, Boraginaceae families were each mentioned in 9 (6%) GeC-HSHR, while Urticaceae and Rhamnaceae were mentioned in 8 (6%) GeC-HSHR. Eighteen (12%) GeC-HSHR contained Matricaria recutita L., while Coffea spp L. and Symphytum officinale L. represented 9 GeC-HSHR (6%) each. Calendula officinalis L., Urtica dioica L. and Rhamnus catharticus L. were contained in 8 GeC-HSHR (6%) each (Table 2).

Aqueous extraction was the main processing of plants in both regions (51 ItR-HSHR, 41%; 64 GeC-HSHR, 44%). Direct use of plant parts without an extraction process came second (43 ItR-HSHR, 34%; 43 GeC-HSHR, 30%). In both regions also alcohol or oil/fat was used as extracting agent, and the use of some commercial products based on plants were reported (Tables 1 and 2). Farmers in ItR prepared 6 ointments, while in GeC 15 ointments were recorded. In 4 ItR-HSHR and 6 GeC-HSHR lard served as both extraction agent and ointment base. In 2 ItR-HSHR and in 7 GeC-HSHR beeswax was used as additional ointment base. In 2 GeC-HSHR milking grease (mineral ointment) alone or in combination with beeswax was the ointment-base.

Concentration of dry plant equivalent in the end-product was estimated for 95 ItR-HSHR (76%), either by using plant material provided by the interview partner (17 ItR-HSHR, 13.5%), with plant samples of our collection of herbal drugs (37 ItR-HSHR, 29.5%), or by assessment of administered volume of mentioned plant and subsequent weighing (41 ItR-HSHR, 33%). For 30 ItR-HSHR (24%), no estimation was possible. The same procedure was used in GeC, leading to estimation of concentration of plant equivalent in the final product for 84 GeC-HSHR (58%): in 33 GeC-HSHR (23%) by weighting the original plant, in 40 GeC-HSHR (27.5%) with our reference drugs, and in 11 cases (7.5%) the concentration was estimated by assessment of administered volume of mentioned plant and subsequent weighing. For further 61 GeC-HSHR (42%) it was not possible to estimate plant weight.

A complete list of ItR-UR and GeC-UR is available in Additional file 1. A total of 205 ItR-UR were reported for the 125 ItR-HSHR (Table 3). Thirty-nine of these (19%) were used as prophylactics, while 166 ItR-UR (81%) were therapeutics. For the 145 GeC-HSHR a total of 209 GeC-UR were described (Table 4), of which 199 GeC-UR (95%) were used for therapy, and 10 as prophylactics (5%). In both regions topical and oral administration were most frequently employed, and afflictions of the skin and the gastrointestinal tract were the main categories of use (Tables 3 and 4, Fig. 2). Ruminants were predominant as target animal species in both research regions. In ItR there was a nearly equal distribution between small ruminants and cattle, while in GeC mainly cattle were the intention of the treatment.

For each UR further information was collected, such as date of last use, frequency of use within the last five years, need for additional therapies, and source of knowledge (Table 5). While in both regions about half of all UR have been used during the last year, 34% of the ItR-UR and 16% of the GeC-UR were used the last time more than 10 years ago.

The degree of satisfaction with UR outcomes was measured for 183 ItR-UR and 196 GeC-UR, and average VAS of 87.2 mm and 77.7 mm respectively, were reported (Table 5 and Additional file 1).

Sex and age distribution of dialogue partners in the two study regions were comparable between the research regions and with former Swiss studies (median age 53 [23] and 55 [22] years respectively) but in contrast to dialogue partners in Italian studies (74 [25], 67 [26], and 72 [27] years in average). This may be due to differing methods for recruitment of dialogue partners. However, if this trend will be confirmed in future ethnoveterinary studies, it may be indicative of a higher interest for traditional ethnoveterinary knowledge in the younger generation of Swiss farmers.

Effectiveness of the recruitment methods significantly differed in the two regions, as in ItR 15 out of 25, but only 2 out of 31 interview partners in GeC were recruited via snow-ball sampling [29]. This may be due to cultural differences. In GeC persons apparently felt comfortable in proposing themselves for the project, whereas dialogue partners from ItR seemed more reticent in the beginning. However, after meeting the interviewer in person they were willing to participate, and to help in finding more dialogue partners via their personal contacts. This leads in the end to an overrepresentation of ItR considering the total number of farms of both regions (about 10’000 in GeC and about 1,100 in ItR).

Interviewed farmers in GeC remain after retirement on the farm, while in ItR farms were so small that they often closed with the retirement of the farmer. These small farms have been operated mainly as a second income and were economically unattractive for the following generation. This difference of the two regions might explain also the higher percentage in ItR of remedies used for the last time more than 10 years ago. In ItR the retired farmers have no possibilities to use their knowledge while retired farmers of GeC can assist the following farming generation and transmit their knowledge. One interview in ItR took place just the day after one of Ticino organic farming pioneers sold off his last 4 dairy cows, given that neither relatives nor friends were willing to continue his activity and to pass his knowledge on to a next generation. This example underlines the necessity of ethnoveterinary research for documenting ethnoveterinary practices, in particular, in regions of smallholding farms.

While in both research regions plant material was purchased in almost 40% of the cases, more cultivated plants were used in GeC (21%; ItR-HSHR, 14%), and plants were slightly more often collected in the wild in ItR (45%; GeC-HSHR, 39%). Commercial products were less used in ItR than in GeC. This may be, in part, explained by the geographical and topographical differences between the two regions, given that ItR is considerably less urbanized and populated. Earlier studies from Switzerland [22] and, even more, from Italy [24‐28], reported collection in the wild as the most frequent way for obtaining plants. Regarding the Italian studies methodological differences may, in part, explain the outcomes, given that these studies focused more on botanical aspects (explicitly looking for wild plants), while the focus of Swiss studies were more on veterinary outcomes. However, in Switzerland medicinal plants are more widely available in local pharmacies or druggist stores, while in Italy they are typically only available in the few herbalist shops.

Regarding extraction procedures, in ItR and GeC one third of HSHR were without any extraction. Water extractions were reported frequently in both regions. Infusions appear to be more common in GeC, and decoctions seem to be slightly more common in ItR. Some differences might be directly connected with the commonness of some plant species: e.g. chamomile is typically prepared by infusion, and more common in GeC than in ItR. Other differences might be connected to local cultural aspects: e.g. Coffea spp is prepared as infusion in the northern territories, while in ItR is still reported the old custom of boiling Coffea spp. Former Swiss studies reported similar outcomes regarding extraction procedures, with infusion being the most common mode of extraction, while approximately one third of HSHR were used without any extraction [22, 23]. The same is true for the Italian studies which report a high number of plant species used directly as feed or feed additive, albeit often without obvious medicinal purpose. In contrast, infusions or decoctions appear to be linked to treatment of specific diseases [24‐28]. In the perception of the Italian dialogue partners the oral administration of unprocessed plant material is more likely to be a feed additive than a medicine, while some kind of processing or extraction is required to create a “real drug” for the treatment of a disease.

As in former Swiss [22, 23] or Italian studies [24‐28] alcohol was less used as extracting agent (“Schnaps” (GeC) or “grappa” (ItR) with 45 up to 60% vol), normally at room temperature. Exclusively in ItR the use of “flemma”, a sub-product of grappa distillation with 16% vol, and decoctions based on red wine and Syzygium aromaticum (L.) Merr. & L.M. Perryor Cinnamonum verum J. Presl. respectively (“vin brulè”) were reported. The latter extraction process was also reported from northern Italy [27].

Due to the high importance of sheep and goat rearing in ItR, small ruminants were more frequently mentioned in ItR-UR than in GeC-UR (Tables 3 and 4). However, despite the high economic importance of pig and poultry farming and the specific search for dialogue partners involved in this sector in GeC [17], only 4% and 8% of GeC-UR were reported for hens and pigs respectively. In contrast, 8% of ItR-UR were directed towards treatment or prevention of diseases in chicken. This may be related to the low number of chicken per farm kept in ItR compared to GeC, as farmers may be more likely to treat “single” animals than an indistinct large group. Ethnoveterinary remedies seem to be uncommon for the treatment in intensive commercial chicken and pig farms where no individual treatment is possible. These animals were normally treated as a whole herd or flock, but an ethnoveterinary tradition for the treatment of larger herds or flocks (in intensive livestock production) does not exist. This hypothesis is supported by the fact that in European ethnoveterinary studies pigs and poultry are generally less frequently mentioned compared to other animal species such as cattle [2]. This is also true for data from former Swiss [22] and Italian studies [24‐28].

Disorders against which UR were directed to, were categorized according to the anatomical therapeutic chemical classification system for veterinary medicinal products ATCvet [33] (Fig. 2). In both ItR and GeC, treatments were mainly directed to dermatological (QD) and alimentary tract disorders (QA). These data are consistent with overall data from Europe [2] as well as from Swiss studies [22, 23].

Although differences are reported regarding specific QA pathologies addressed: ItR counts a considerably lower number of UR for treatment of diarrhoea (5%), which is in contrast to GeC-UR (23%), to former Swiss studies [22, 23], and the fact that calf diarrhoea is reported as one of the major health problems in young cattle [36]. In ItR musculoskeletal (QM) and genito-urinary (QG) treatments seem to be more common than in GeC (Fig. 2). In contrast, ItR counts only one UR to treat mastitis, while 13 GeC-UR were mentioned by dialogue partners. However mastitis is considered to be one of major problem in dairy herds [37] and various plant species were reported in previous Swiss [22, 23] and European [2] studies to treat mastitis.

One reason for the differences between both regions might be the high importance of small ruminants in ItR, with a different kind of problems. Antiparasitic treatments, both for endo- and ecto-parasites, are a major concern for ItR farms. These data seem consistent with previous finding which highlighted parasitosis as one of the major issues in sheep and goats [37, 38].

Most of the further information (Table 5) was comparable between both research regions as well as with former Swiss studies [22, 23] but compared to ItR-UR GeC-UR were more frequently reported to be added by another complementary therapy (e.g. homeopathy).

The source of knowledge “Courses and Education” was much more frequently reported for GeC than for ItR (22% versus 3%) and former Swiss studies [22, 23]. This might be due to the higher offer of such courses in GeC through the farmer’s advisory service. The source of knowledge “Ancestors, relatives and friends” was highly overrepresented in ItR-UR (85% versus 50% GeC-UR) and might be a sign for the regional seclusion of ItR. The satisfaction with the outcome of the UR of our both study regions (ItR 87 mm, GeC 78 mm) is comparable to previous Swiss studies which showed values from 80–85 mm in average [22, 23]. None of this further information is available from Italian studies [24‐28].

Dosages reported by farmers represent their individual empirical knowledge but might be the base for further clinical research, as well as a starting point even for veterinarians to gain own experience [6]. Most of the 27 determined drug dosages of our study (Tables 6 and 7) are well comparable between the both research regions, with previous Swiss studies [22, 23] and human and veterinary literature [39‐42] with three exceptions: (1) Coffea spp. is in both research regions applicate in a considerable higher oral dose (ItR: 1.7 g/kg^0.75; GeC: 1.2 g/kg^0.75), as in previous Swiss studies (0.4 g/kg^0.75), (2) Thymus vulgaris L. is considerably lower dosed (only determined for GeC: 1.2 g/kg^0.75) than in one previous Swiss study (2.2 g/kg^0.75) and (3) for Urtica dioica L. was a considerable different dosage determinable in both research region (ItR: 13.8 g/kg^0.75; GeC: 0.1 g/kg^0.75) but even between previous Swiss studies some differences and a high diversity was detectable (2.4 and 0.5 g/kg^0.75). In eight cases we could determine Swiss ethnoveterinary based dosages for the first time (Table 6). Italian data regarding dosages were not available.

Since ethnoveterinary data from Italy [24‐28] were collected with different methodologies than in Switzerland we decided to focus on the reported plant species to highlight similarities and differences of the different regions (Fig. 3 and Additional file 2). GeC as well as ItR shared about one quarter of the reported plant species with the Italian studies while four fifth (GeC) and two thirds (ItR) are in accordance with former Swiss studies [22, 23]. A comparison with German ethnoveterinary data would have been of interest but was not possible because such data are not available.

However, the comparison of Swiss and Italian ethnoveterinary data shows a higher similarity than the comparison of Romanian with Spanish, Italian and Albanian data [13], but it is comparable with the overlapping of southern Italian with Tunisian data [15]. This suggests that ethnoveterinary tradition may change with growing geographic distance.

Interestingly, no plant species of GeC corresponds exclusively to a plant species of ItR or Italy but about one quarter of the GeC plant species corresponds exclusively with former Swiss studies. In contrast only one ItR plant species overlaps exclusively with Italian (Gentiana purpurea L., which also shares indication [26]) but 5 exclusively with former Swiss studies. To our surprise ItR data are closer to former Swiss [22, 23] than to Italian studies, even though we included explicitly only studies of mountain regions of northern Italy [24‐28]. However, with one third of the plant species being exclusively reported from ItR compared to only one fifth from GeC, ItR shows a slightly higher independence in this aspect than GeC. Most of the exclusively reported plant species are cited only with one UR. Three or more UR are reported only for Oryza sativa L. and Urtica urens L. (ItR-UR) and Armoracia rusticana P. Gaertn. & al. and Berberis vulgaris L. (GeC-UR). U. urens L. is one of the most often reported species in ItR, while only a few European ethnobotanic surveys report its use to treat animals [43‐45]. Four plant species each of ItR (Allium ursinum L., Artemisia campestris L., Cucurbita maxima Duch. and Eugenia caryophillata Thunb.) and GeC (Alchemilla mollis (Buser) Rothm., Armoracia rusticana P. Gaertn. & al., Cinnamomum camphora (L.) J.Presl. and Panax ginseng C.A. Mayer) have never been cited before in European ethnoveterinary literature to treat animal diseases [2].

About half of the plant species (22 species, Fig. 3) were named in both research regions. Some of them in the context of the same indications: e.g. Matricaria recutita L. is used in both regions to treat gastrointestinal as well as dermatological disorders. However, ItR and GeC share less than half of the plant species representing their usualness with more than 4 UR (Table 8): e.g. Malvaceae family, well known from previous Swiss [22, 23] and European studies [2] as a dermatological agent, is apparently well known only in ItR. Information regarding the frequency of use is not available from Italian studies [24‐28]. However, other studies show bigger differences in ethnoveterinary tradition even from neighbouring regions of the same linguistic area in the same country [14]. In that respect Switzerland shows a relative high consensus in ethnoveterinary data.

Natural conformation of the territories may explain at least some of the major differences between the two areas of the same country: for example Arnica montana L. naturally grows in the alpine regions and thus probably is associated with a higher number of ItR-UR than GeC-UR. Another example may be Urtica urens L. use in ItR, where is preferred to Urtica dioica L., probably because of its local prevalence on country side.

The attitude towards phytotherapy (for humans) is generally positive in Switzerland [46], and research in the field has been actively pursued over the last decades [47]. Availability of herbal drugs and finished products is therefore rather good. In contrast, phytotherapy is much less popular in Italy, and most of the plants used for veterinary purposes were harvested from the wild. This may, at least in part, explain the differences in the spectrum of plant species reported in the ethnoveterinary surveys. Nevertheless, how much differing policies and attitudes regarding medicinal plants are responsible for these national differences remains an open question. Different farm structure and main livestock species and, hence, different major pathologies likely also contributed to these differences. However, geographical and linguistic barriers on the one side, and political borders on the other side seem to contribute to the relative uniqueness of ItR ethnoveterinary knowledge, whereby political borders seem to be a higher barrier than mountain ranges.