Contamination with ergot bodies (Claviceps purpurea sensu lato) of two horse pastures in Northern Germany.

Because the occurrence of Claviceps in European pastures may have been overlooked to cause serious health problem for grazing animals, we documented the degree of Claviceps contamination in two horse pastures and estimated whether the horses could have ingested a critical quantity of alkaloids. We counted the Claviceps sclerotia and determined alkaloid levels using high performance liquid chromatography with fluorescence detection. Depending on the location, the number of sclerotia varied from 0.09 to 0.19 per square meter (central area) and from 0.23 to 55.8 per square meter (border strips). Alkaloid levels in individual sclerotia also varied in different genera of grasses, ranging from 0.98 ± 0.17 µg/kg in Agrostis sp. to 25.82 ± 9.73 µg/kg in Dactylis sp., equivalent to 0.98 µg/kg and 7.26 mg/kg. Sclerotia from Dactylis contained high levels of ergosine (0.209 % ± 0.100 %) and ergocristine (0.374 % ± 0.070 %). Depending on the localization in pastures, alkaloid levels in forage (dry matter, DM) ranged from 16.1 to 45.4 µg/kg in central areas and from 23.9 to 722 µg/kg in border strips. The amount of alkaloids that a horse could have ingested depended on its daily DM uptake, which was higher in the central areas (5.85 kg/day) than in the border strips (2.73 or 0.78 kg/day). In the central areas, this amount of alkaloids ranged from 94.2 to 265.9 µg/day; and in the border strips, from 65.3 (in 2.73 kg DM/day) to as much as 563.8 µg/day (in 0.78 kg DM/day). All these amounts are higher than the European averages for alkaloids ingested by horses via feedstuffs.

[Yellow oat grass intoxication in horses: Pitfalls by producing hay from extensive landscapes? A case report]. / Goldhafer-Intoxikation bei Pferden: Wie sicher ist die Heuqualität von extensiven Standorten? Ein Fallbericht.

Vitamin-D intoxication by yellow oat grass is often reported under the syndrome of enzootic calcinosis in ruminants in the upper regions of the Alps. The intake of Trisetum flavescens in ruminants and horses induces calcification of soft tissue, including vessels, tendons and ligaments, lung, heart and kidneys. Clinical symptoms, including a reluctance to move, inappetence, body-weight loss and impaired organ function, are frequently observed. To date, there are only a very few case reports about yellow-oat-grass intoxication in horses. The present case report describes Vitamin-D intoxication by yellow oat grass in a riding stable in Thuringia, Germany. The horses, which were fed hay with a 50% contamination of Trisetum flavescens, displayed symptoms, including inappetence, body-weight loss, colic, polydipsia and polyuria. The hay, contaminated with Trisetum flavescens, was harvested from an extensively cultivated landscape according to the European Fauna-Flora-Habitat (FFH)-directive. The present case report demonstrates the pitfalls in producing hay from extensively used landscapes and indicates some peculiarities of Vitamin-D metabolism in horses.

[Alimentary intake of opioid alkaloids by horses. Hazards due to poppy-containing feeds]. / Alimentäre Aufnahme von Opioid-Alkaloiden durch Pferde. Gefahren durch mohnhaltige Futtermittel.

Opioid alkaloids were identified in the urine of horses during an anti-doping control and in a case of intoxication. In both cases, it was suspected that the horses had ingested poppy-contaminated feed. To verify this suspicion, possible opioid alkaloid sources in Germany were identified through a literature research. Additionally, the contaminated feed was botanically and chemically analysed. The results indicated that both cases were most probably caused by the poppy in the feed. This highlights the previously underestimated risk of an intake of poppy-contaminated feed in horses. Recommendations are formulated for the prevention of positive doping-test results and intoxications by poppy-contaminated feeds in horses. Furthermore, a threshold for morphine in urine samples in competing horses is proposed.

[Accident report: animal nutrition in veterinary medicine--actual cases: houndstongue (Cynoglossum officinale) in pasture--a health hazard for horses]. / Fallbericht: Tierernährung für Tierärzte--aktuelle Fälle: Hundszunge (Cynoglossum officinale) im Weideaufwuchs--ein Risiko für die Gesundheit von Pferden.

Meteorism and colics were observed in horses after grazing on young pasture. The botanical analysis of a sample as taken by the owner revealed a great diversity of grasses, herbs and legumes. Houndstongue (Cynoglossum officinale) in its rosette stage was identified in amounts of 1% of the total sample, although this cannot be regarded as representative for the composition of the green fodder. This plant has been reported to be highly toxic for horses and other species, mainly during the early growth stadium due to its contents of pyrrolizidin alkaloids with a strong hepatotoxic activity. In the present case it remained unclear, whether the horses actually ingested this poisonous plant in relevant amounts. In general it has to be emphasised, that a contamination especially of hay or silage bears a severe risk for horses. The contamination of green fodder with houndstongue can be a serious problem for the feeding practice in certain regions (dry grassland, loess or shell lime soil, extensive management).