Bone marrow and kidney fat as indicators of condition in reindeer
Abstract
Back-fat depth, kidney-fat index (KFI), fat and triglyceride contents in femur and metatarsal marrows were measured from 92 semi-domesticated reindeer (Rangifer tarandus tarandus L.) in northern Finland during 1980-84. The age of the reindeer varied from 5 months to 10 years and marrow fat content was estimated by five different methods: standard ether extraction, oven-drying (Neiland, 1970), reagent-dry assay (Verme and Holland, 1973), compression method (Greer, 1968) and visual estimation (Cheatum, 1949). The kidney-fat index (Riney, 1955) was significantly related (r=0.892) to the percent marrow fat in femur and metatarsus. The oven-drying method gave high correlations with results obtained by ether extraction and reagent-dry methods. Oven-drying produced a lower mean dry-weight value than reagent-drying (1.31 ±0.36%). The amount of compression had a concave relationship with the ether-extractable fat content of femur and metatarsal marrows. The subjectiveness of the visual estimation technique limited its use. Femur marrow fat contents (dry-weight %) in reindeer which died from starvation varied between 2 - 8%. Metatarsal fat contents were slightly higher. Adult males had a mean triglyceride content of 46.8 |Jmol/g in August in the femur. Adult females had slightly lower values. The amount of triglycerides was significantly related to the ether-extractable fat content of the femur (r=0.914) and metatarsal (r=0.911).Authors retain copyright and grant Rangifer irrevocable and non-exclusive right of publication with the work simultaneously licensed under a Creative Commons Attribution License (CC-BY). This means, among other things, that anyone is free to copy and distribute the content, as long as they give proper credit to the author(s) and the journal. For further information, see Creative Commons website for human readable or lawyer readable versions.