Iron and iron/manganese ratio in forage from Icelandic sheep farms: relation to scrapie

• Published in: Acta Veterinaria Scandinavica
• Main Authors: Jóhannesson T, Eiríksson T, Kristinsson J, Sigurdarson S, Gudmundsdóttir KB
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2006
• Subjects: Veterinary medicine; SF600-1100; Pivot; Iceland
• Online Access: https://doi.org/10.1186/1751-0147-48-16; https://doaj.org/article/6b24f8db1f9e483daa458808d35c8656

Abstract This study was undertaken in order to examine whether any connection existed between the amounts of iron in forage and the sporadic occurrence of scrapie observed in certain parts of Iceland. As iron and manganese are considered antagonistic in plants, calculation of the Fe/Mn ratios was also included by using results from Mn determination earlier performed in the same samples. Forage samples (n = 170) from the summer harvests of 2001–2003, were collected from 47 farms for iron and manganese analysis. The farms were divided into four categories: 1. Scrapie-free farms in scrapie-free areas (n = 9); 2. Scrapie-free farms in scrapie-afflicted areas (n = 17); 3. Scrapie-prone farms (earlier scrapie-afflicted, restocked farms) (n = 12); 4. Scrapie-afflicted farms (n = 9). Farms in categories 1 and 2 are collectively referred to as scrapie-free farms . The mean iron concentration in forage samples from scrapie-afflicted farms was significantly higher than in forage samples from farms in the other scrapie categories (P = 0.001). The mean Fe/Mn ratio in forage from scrapie-afflicted farms was significantly higher than in forage from scrapie-free and scrapie-prone farms (P < 0.001). The results indicated relative dominance of iron over manganese in forage from scrapie-afflicted farms as compared to farms in the other categories. Thus thorough knowledge of iron, along with manganese, in soil and vegetation on sheep farms could be a pivot in studies on sporadic scrapie.