Does the Fat Tailed Damara Ovine Breed Have a Distinct Lipid Metabolism Leading to a High Concentration of Branched Chain Fatty Acids in Tissues? Susana P. Alves 1 , Rui J. B. Bessa 1 , Ma ´ rio A. G. Quaresma 1 , Tanya Kilminster 2 , Tim Scanlon 2 , Chris Oldham 2 , John Milton 3 , Johan Greeff 2 , Andre ´ M. Almeida 1,4,5,6 * 1 CIISA – Centro Interdisciplinar de Investigac ¸a ˜ o em Sanidade Animal, Faculdade de Medicina Veterina ´ria/UTL, Lisboa, Portugal, 2 DAFWA – Department of Agriculture and Food Western Australia, Perth, Western Australia, Australia, 3 Faculty of Natural and Agricultural Sciences, UWA – University of Western Australia, Crawley, Western Australia, Australia, 4 Biotrop, IICT – Instituto de Investigac ¸a ˜o Cientı ´fica Tropical, Lisboa, Portugal, 5 IBET – Instituto de Biologia Experimental e Tecnolo ´ gica, Oeiras, Portugal, 6 BCV, ITQB/UNL – Instituto de Tecnologia Quı ´mica e Biolo ´ gica, Oeiras, Portugal Abstract Fat tailed sheep breeds are known for their adaptation to nutritional stress, among other harsh production conditions. Damara sheep, native to Southern Africa, have recently been exported to other areas of the world, particularly Australia, aiming to produce lamb in semi-arid regions. Damaras have a unique hanging fat tail, a fat depot able to be mobilized under nutritional stress. In this article we perform an in-depth characterization of the fatty acid profiles of the fat tail in underfed and control Damara rams. Profiles were very similar between experimental groups, with the exception of palmitic acid (16:0) that was lower (P = 0.014) in underfed animals. However, the most striking result was the very high proportions of non-terminal branched chain fatty acids found in the fat tail adipose tissue, as well as the gastrocnemius muscle of Damara rams. The muscle of Dorper and Merino rams used in the same experiment did not present non-terminal branched chain fatty acids, suggesting that Damara rams have a unique lipid metabolism. Herein, we interpret this trait relating it to a higher ability of Damara sheep to digest fibrous fodder and to putative differences in the propionate metabolism by comparison to other sheep breeds. Citation: Alves SP, Bessa RJB, Quaresma MAG, Kilminster T, Scanlon T, et al. (2013) Does the Fat Tailed Damara Ovine Breed Have a Distinct Lipid Metabolism Leading to a High Concentration of Branched Chain Fatty Acids in Tissues? PLoS ONE 8(10): e77313. doi:10.1371/journal.pone.0077313 Editor: Wolf-Hagen Schunck, Max Delbrueck Center for Molecular Medicine, Germany Received July 12, 2013; Accepted September 6, 2013; Published October 18, 2013 Copyright: ß 2013 Alves et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: Authors acknowledge financial support from the Department of Agriculture and Food WA (Perth, Western Australia). SP Alves was supported through the grant SFRH/BPD/76836/2011 and AM Almeida was financed by grant SFRH/BPD/90916/2012, and a Cie ˆncia 2007 Research Contract, both from Fundac ¸a ˜ o para a Cie ˆncia e a Tecnologia of the Ministe ´rio da Cie ˆncia, Tecnologia e do Ensino Superior (Lisbon, Portugal). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: aalmeida@fmv.utl.pt Introduction Fat tail and fat rump sheep are characteristic of semi-arid environments and commonly found across vast areas of the globe: Eastern and Southern Africa, the steppes of Central Asia, as well as numerous countries in the Middle-East. The Damara (see Figure 1) is one of such fat tailed sheep breeds characterized by a large body frame and a shedding hair coat. Damaras originated from Southern Angola and Namibia and were later selected in South Africa [1]. Fat tailed sheep are reputed for being highly resilient to harsh environmental conditions such as diseases, parasites, water scarcity or seasonal weight loss, but experimental support for such claims are scarce. Recently, the resistance to feed restriction of male rams of three breeds present in Australia (Merino, Dorper and Damara) was evaluated [2]. Samples of tail adipose tissue of the Damara rams used in that experiment were collected and analysed for fatty acid composition. To our knowledge, no information of fatty acid composition of adipose tissue from Damara tails is available in scientific literature. Moreover, fatty acid composition of adipose tissue of fat tails of other breeds is generally limited to the major fatty acids [3–7] and more detailed fatty acid profiles are scarce [8]. As the tail fat depot is naturally mobilized (increased lipolysis and reduced deposition) in animals submitted to feed restriction, we hypothesized that this would also induce significant changes in fatty acid composition. Thus, our aim was to report the fatty acid composition of adipose tissue of Damara tails and relate it to feed restriction. However, we extended the fatty acid analysis to muscle samples in order to explain the unusual abundance of odd and branched chain fatty acids (BCFA) found in the Damara tail fat. Materials and Methods Animal Experiment All animal work was conducted according to relevant interna- tional guidelines (European Union procedures on animal exper- imentation – Directive 2010/63/EU) that regulate the use of production animals in animal experimentation. These define that in the case of experiments carried out under standard production conditions, no approval from an ethics committee is required. Nevertheless, this experiment was conducted with the approval of the Ethics Committee of the Department of Agriculture and Food Western Australia (DAFWA, Perth, WA, Australia) registered as process 07ME06. The entire trial was conducted under the PLOS ONE | www.plosone.org 1 October 2013 | Volume 8 | Issue 10 | e77313