A research team from The University of Nottingham has carried out the first
molecular1 characterisation of the African elephant's
adipose2 tissue(脂肪组织) -- body fat. This new information will form the basis of future studies aimed at securing the health and future survival of captive elephants. The population of captive elephants, both Asian and African, in Europe and North America is not self-sustaining, largely due to poor fertility, resulting in a fewer baby elephants being born. It is acknowledged that if a solution for these reproductive difficulties cannot be found quickly, captive elephants will face demographic
extinction3 in North American zoos within the next 50 years.
This new study, carried out by a team of scientists at the School of Veterinary Medicine and Science, will form the building blocks for later studies that will help scientists start to identify important dietary
components5 for health and reproduction in African elephants to enable better management of this species in
captivity6 and in the wild.
The research, Molecular Characterization of Adipose Tissue in the African Elephant, led by Dr Lisa Yon, and in equal part by her colleagues Dr Nigel Mongan, Dr Richard Emes and Dr Alison Mostyn, has been published in the open access journal PLOS ONE.
Using
expertise7 in molecular biology and bioinformatics at the Nottingham
vet4 school and with access to unique samples from the African elephant researchers were able to explore some important basic biological questions to achieve a better understanding of elephants.
Leptin -- a
hormone8 made by fat cells to regulate the amount of fat stored in the body -- is a crucial molecular link between
nutritional9 status, amount of adipose tissue and fertility in many species. This research has shown that it has a similar function in the African elephant.
Dr Yon said: "This research provides important information on the structure and function of adipose tissue in the African elephant, highlighting the crucial
genes10 and
nutrients11 present during different times of life -- particularly reproduction and
lactation(哺乳)."
Since the discovery of Leptin, adipose tissue has been shown to play a key role in reproduction, energy sensing and regulation, and inflammatory responses. It has been linked with reproductive activity both in terms of the
onset12 of puberty and in maintenance of reproductive function so it may play an important role in building up and maintaining the elephant's reserves to ensure health and fertility.
This work forms an important first step to help maintain a healthy, reproductively
viable13 captive population. This would also eliminate the need to catch additional animals from the wild to supplement the captive population.
Dr Yon said: "The information we gained can help us to know how to better provide for elephants' dietary needs, and what possible impact this may have on their reproductive success. These same methods can be
applied14 to further our understanding on a range of domestic or non-domestic species."
Elephant samples were obtained from management-organized
culling16 operations in Save Valley Conservancy (SVC) in Zimbabwe during 2009-2011. The Zimbabwe Parks and Wildlife Management Authority (PWMA) gave permits to SVC to
cull15 the animals and SVC gave the authors permission to use the samples. No animals were killed specifically for this study, and all permission was obtained from the relevant authorities.