Variations in the concentration of zinc in the blood of Icelandic horses

Abstract

The effect of factors including the horses' farm environment, their sex and age and whether they suffered from summer seasonal recurrent dermatitis (sweet itch) on the concentrations of zinc in the plasma, whole blood and blood cells of 104 Icelandic horses was investigated. Its concentration in plasma varied significantly between farms (P<0.01), but its concentration in blood and blood cells was not influenced by any of the variables. The concentration of zinc in the blood cells was 10.5 times greater than in plasma, but its concentration in plasma was not correlated with its concentration in whole blood or blood cells owing to the variability in the proportion of whole blood zinc present in plasma (relative plasma zinc), which ranged between 9 and 24 per cent. This variability was significantly influenced by a three-way interaction between farm, sex and sweet itch (P<0.05). Relative plasma zinc was positively correlated with absolute plasma zinc (r=0.78, P<0.001) and negatively correlated with whole blood and blood cellular zinc (r=-0.58, r=-0.71, P<0.001).

Serum Zinc Levels and Their Relationship with Diseases in Racehorses

“…One reason for this difference may be environmental differences, such as weather, feedstuffs, grazing times, exercise intensity or daily routine. Previous reports have shown significant differences between farms [18] and/or stables [34]. In this study, there was a significant difference in serum zinc levels only between the highest (65.5 ± 8.9 µg/dl) and lowest (54.9 ± 4.9 µg/dl) levels seen among the 24 stables.…”

“…On the other hand, significant differences were not observed in tying-up syndrome and controls. Five horses with tying-up syndrome showed high creatinine kinase levels (10,506,12,100,13,140,18,308 and 80,833 U/l). The collapse of muscle tissue is the main clinical pathogenesis in tying-up syndrome, but serum zinc did not vary with physiological response on first examination.…”

“…The present results showed reference values from 41 to 79 µg/dl in Thoroughbred racehorses. Previous reports have shown various serum zinc levels (mean ± SD), 111 ± 45 µg/ dl (pasture), 170 ± 54 µg/dl (stable) in Thoroughbreds [34], 47 ± 11 µg/dl (pasture), 47 ± 9 µg/dl (stable) in Thorough-breds [6], 65.4 ± 9.8 µg/dl in Icelandic horses [33], 58.8-66.0 µg/dl (pasture) in Icelandic horses [18], 46.0-59.0 µg/dl in Warmbloods [5] and 42.0-87.0 µg/dl in various breds [21]. One reason for this difference may be environmental differences, such as weather, feedstuffs, grazing times, exercise intensity or daily routine.…”

“…In horses, associations between zinc deficiency and anorexia, reduced growth rate, parakeratosis, alopecia [11], osteochondrosis [10] and white line disease [12] have been reported. Previous studies have reported various equine reference values, including 111.2 ± 45.8 µg/dl on pasture and 170.0 ± 52.3 µg/dl in stable [34], 47 ± 11 µg/dl on pasture and 47 ± 9 µg/dl in stable [6], 58.8-66.0 µg/dl on pasture [18], 65.4 ± 9.8 µg/dl [33], 46.0-59.0 µg/dl [5] and 42.0-87.0 µg/dl [21]. These results suggest large differences in horse management.…”

Wie gut reflektieren Spurenelemente im Serum die entsprechende Versorgung beim Pferd?

“…So wurden z. B. bei Islandpferden, die mit einer ausgeprägten Form des Sommerekzems auffielen, niedrigere Plasma-Zn-Konzentrationen im Vergleich zu ge-sunden Islandpferden gemessen[8]. Bei Vollblütern kam es im Verlauf von fieberhaften Infektionen zu einem Abfall der Serum-Zn-Gehalte[9].In Bezug auf die Fütterung besitzen die verwendeten Zn-Verbindungen einen erheblichen Einfluss auf die Plasmabzw.…”