EFFECT OF CALCIUM AND CHOLECALCIFEROL SUPPLEMENTATION ON SEVERAL PARAMETERS OF CALCIUM STATUS IN PLASMA AND URINE OF CAPTIVE ASIAN (ELEPHAS MAXIMUS) AND AFRICAN ELEPHANTS (LOXODONTA AFRICANA)

Abstract

Abstract:The aim of the current study was to assess the effect of oral calcium and cholecalciferol supplementation on several parameters of calcium status in plasma and urine of captive Asian (Elephas maximus; n ¼ 10) and African elephants (Loxodonta africana; n ¼ 6) and to detect potential species differences. Calcium and cholecalciferol supplementation were investigated in a feeding trial using a crossover design consisting of five periods of 28 days each in summer. From days 28-56 (period 2), elephants were fed the Ca-supplemented diet and from days 84-112, elephants were fed the cholecalciferol-supplemented diet (period 4). The control diet was fed during the other periods and was based on their regular ration, and the study was repeated similarly during winter. Periods 1, 3, and 5 were regarded as washout periods. This study revealed species-specific differences with reference to calcium and cholecalciferol supplementation. Asian elephants showed a significant increase in mean plasma total calcium concentration following calcium supplementation during summer, suggesting summerassociated subclinical hypocalcemia in Western Europe. During winter, no effect was seen after oral calcium supplementation, but a significant increase was seen both in mean plasma, total, and ionized calcium concentrations after cholecalciferol supplementation in Asian elephants. In contrast, evidence of subclinical hypocalcemia could be demonstrated neither in summer nor in winter in African elephants, although 28 days of cholecalciferol supplementation during winter reversed the decrease in plasma 1,25(OH)2-cholecalciferol and was followed by a significant increase in mean plasma total calcium concentration. Preliminary findings indicate that the advisable permanent daily intake for calcium in Asian elephants and cholecalciferol in both elephant species at least during winter might be higher than current guidelines. It is strongly recommended to monitor blood calcium concentrations and, if available, blood parathyroid hormone levels to adjust the nutritional supplementation for each individual elephant.

Zoo elephant research: contributions to conservation of captive and free‐ranging species

“…Importantly, zoo elephant research has repeatedly identified differences between African and Asian elephants. Different drug‐dosage requirements (Bechert et al ., ), reproductive pathologies (Hildebrandt et al ., ; Brown et al ., ), digestive physiologies (Dierenfeld, ; van Sonsbeek et al ., ), pheromones (Rasmussen & Schulte, ) and susceptibility to EEHV (Bronson, E., et al ., ) are a few such examples. Nonetheless, African and Asian elephants have typically been viewed and managed collectively as ‘elephants’ in captive settings.…”

“…Typically, dietary supplementation with vitamin E is required to match values found in free‐ranging elephants, and there also appears to be a species‐specific response to vitamin E (Swanson et al ., ) that requires further investigation. Vitamin D and calcium dynamics in both species of elephants have been eloquently examined by seasonal studies and supplementation in a zoo setting (van Sonsbeek et al ., ). Species‐specific responses were documented, which may relate to habitats and available nutrient resources within which each species evolved (van Sonsbeek et al ., ).…”

“…Vitamin D and calcium dynamics in both species of elephants have been eloquently examined by seasonal studies and supplementation in a zoo setting (van Sonsbeek et al ., ). Species‐specific responses were documented, which may relate to habitats and available nutrient resources within which each species evolved (van Sonsbeek et al ., ). However, more such comparative and well‐designed studies are required for us to truly understand similarities and differences, and optimize nutrition, for these species.…”

Review of the management of the Asian elephant Elephas maximus EEP: current challenges and future solutions

“…Research has also been carried out into hypocalcaemia in captive elephants, because there are some indications that hypocalcaemia is associated with dystocia (difficult births) (van Sonsbeek et al , ). Although causality between hypocalcaemia and dystocia in elephants is still unproven, it has been reported in other species, such as cattle and sheep, and there are some indications that this relationship also applies in elephants (Stubbings, ; Smith & Risco, ; van Sonsbeek et al , ). Therefore, veterinary experts recommend that elephants are provided with more calcium and cholecalciferol than was prescribed by previous guidelines (van Sonsbeek et al , ).…”

Low coverage sequencing of two Asian elephant (Elephas maximus) genomes

“…Asian elephants also have fewer ribs, more molar plates and a small intestine twice as long as that in African elephants [1,2,4]. The elephant species also differ in their nutritional needs [5] and susceptibility to infectious diseases [6]. …”