Goldhafer-Intoxikation bei Pferden: Wie sicher ist die Heuqualität von extensiven Standorten?

Abstract

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.

Enzootic calcinosis in horses grazing Solanum glaucophyllum in Argentina

“…Clinical signs and lesions in these horses were comparable to those of T. flavescens intoxication in this species. 1…”

“…2,19 EC induced by this plant, locally referred to as enteque seco, causes considerable economic losses to the livestock industry. 19 Other plants are well-recognized causes of EC worldwide, 17 including Nierembergia veitchii 16 and Nierembergia rivularis in South America, 8 Cestrum diurnum in North America, 7,11 Trisetum flavescens in Europe, 1,6,10,18 and Solanum torvum in Oceania. 13 All of these plants are within the Solanaceae family, except for T. flavescens, which is a grass in the family Poaceae.…”

“…12,14 Hay contaminated with calcinogenic plants constitutes another potential source of poisoning for horses and cattle. 1 EC is more frequent in ruminants and rare in monogastric species; however, natural cases have been reported in pigs 3 and horses (Gimeno EJ, pers. comm., 2017).…”

“…12,17 Based on the pleiotropic physiological role of vitamin D in classical target tissues, as well as evidence of the extraskeletal effects of calcitriol, 4 it is evident that the pathogenesis of EC is highly complex. Experimental studies performed in different animal models that administered ground leaves of S. glaucophyllum orally or intraruminally have shown changes in cell proliferation, differentiation, and apoptosis in the aorta and lungs, 15 20 In horses, EC has been associated primarily with the ingestion of T. flavescens in Europe, 1,10,18 and less frequently with C. diurnum in the United States. 11 EC has occurred in horses after grazing calcinogenic plants, 10 and also after ingestion of calcinogenic plants present in hay.…”

“…11 EC has occurred in horses after grazing calcinogenic plants, 10 and also after ingestion of calcinogenic plants present in hay. 1 Clinical signs include weight loss, lameness, disturbances of movement, kyphosis, pain on palpation of the flexor tendons and suspensory ligaments, polyuria, and recurrent colic. 1,[10][11][12] Reports describing EC in horses are scarce in the literature, and none of them involve ingestion of S. glaucophyllum, to our knowledge.…”