Good reproduction and health status in a genetically monomorphic species, the cheetah
In this project we investigate the effect of the low genetic variability of cheetahs on their reproductive performance and their health status. We demonstrate that free-ranging cheetahs reproduce successfully and have a strong immune system despite their genetic monomorphism. We also demonstrate that breeding challenges of captive cheetahs can be improved with a well-directed management.
|Involved Department(s):||Dept Evolutionary Ecology, Dept Evolutionary Genetics, Dept Wildlife Diseases, Dept Reproduction Biology|
|Leibniz-IZW Project Leader(s):||Bettina Wachter (Dept Evolutionary Ecology)|
|Leibniz-IZW Project Team:||Jörg Melzheimer, Rubén Portas, Rebekka Müller, Ralf Röder, Maria Serocki (all: Dept Evolutionary Ecology), Alexandre Courtiol, Alexandra Weyrich (all: Dept Evolutionary Genetics), Gábor Czirják (Dept Wildlife Diseases), Martin Dehnhard (Dept Reproduction Biology)|
|Current Funding Organisation:||Messerli Foundation, German Science Foundation (DFG)|
|Research Foci:||Understanding traits and evolutionary adaptations|
|Understanding wildlife health and disturbed homeostasis|
|Understanding the environmental context|
|Improving population viability|
Cheetahs are known for their low genetic variability. This was used for decades, together with other reasons such as human conflicts and habitat fragmentation, to explain why cheetahs are threatened and why their populations are declining globally. A low genetic variability is generally thought to be linked with a low reproductive performance and high disease susceptibility. Using the cheetah as an example, we show that this link does not hold for this species. Free-ranging females reproduce successfully compared to females kept in enclosures. In cooperation with the Department of Reproduction Management we demonstrated that this is due to the age at first reproduction and that reproduction in zoos can be improved when females are allowed to breed early in their lives.
Similar to genetic variability, allostatic load (“stress”) has no effect on the reproductive performance of cheetahs. This result was obtained in cooperation with the Department of Reproduction Biology, in whose endocrine laboratory methods for the measurement and validation of androgens (sexual hormones) and glucocorticoids (“stress” hormones) in faeces of cheetahs were established.
An additional method to measure the stress hormone cortisol in cheetah hairs was developed recently. The low genetic variability is, however, linked with a low adaptive immunity. This is because the immune genes, such as the major histocompatibility complex (MHC), are not very variable as we demonstrated in cooperation with the Department of Evolutionary Genetics. Nevertheless, free-ranging cheetahs have a good health status and show no clinical signs of infectious diseases. In collaboration with the Department of Wildlife Diseases we demonstrated that cheetahs compensate their weak adaptive immunity with a strong innate immunity. This innate immunity is stronger than that of leopards, which have a high MHC variability, and also stronger than that of other large carnivores. In cooperation with the Department of Evolutionary Genetics we investigate the mating system of free-ranging cheetahs as well as epigenetic modifications which regulate the expression of genes.
Seltmann A, Schares G, Aschenborn OHK, Heinrich SK, Thalwitzer S, Wachter B*, Czirják GÁ* (2020): Species-specific differences in Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti seroprevalence in Namibian wildlife. PARASITES VECTORS 13, 7. doi:10.1186/s13071-019-3871-3.
Costantini D, Czirják GÁ, Melzheimer J, Menges V, Wachter B (2018): Sex and species differences of stress markers in sympatric cheetahs and leopards in Namibia. COMP BIOCHEM PHYSIOL PART A 227, 8-13. doi:10.1016/j.cbpa.2018.09.002.
Costantini D, Wachter B, Melzheimer J, Czirják GÁ (2017): Socioecological and environmental predictors of physiological stress markers in a threatened feline species. CONSER PHYSIOL 5(1). doi:10.1093/conphys/cox069.
Heinrich SK, Hofer H, Courtiol A, Melzheimer J, Dehnhard M, Czirják GÁ, Wachter B (2017): Cheetah have a stronger constitutive innate immunity than leopards. SCI REP 7, 44837. doi:10.1038/srep44837.
Heinrich SK, Wachter B, Aschenborn OHK, Thalwitzer S, Melzheimer J, Hofer H, Czirják GÁ (2016): Feliform carnivores have a distinguished constitutive innate immune response. BIOL OPEN 5, 550-555. doi:10.1242/bio.014902.
Krengel A, Cattori V, Meli ML, Wachter B, Böni J, Bisset LR, Thalwitzer S, Melzheimer J, Jago M, Hofmann Lehmann R, Hofer H, Lutz H (2015): Gammaretrovirus-specific antibodies in free-ranging and captive Namibian cheetahs. CLIN VACCINE IMMUNOL 22, 611-617. doi:10.1128/CVI.00705-14.
Ludwig C, Wachter B, Silinski-Mehr S, Ganswindt A, Bertschinger H, Hofer H, Dehnhard M (2013): Characterisation and validation of an enzyme-immunoassay for the non-invasive assessment of faecal glucocorticoid metabolites in cheetahs (Acinonyx jubatus). GEN COMP ENDOCRINOL 180, 15-23. doi:10.1016/j.ygcen.2012.10.005.