title: Systemic effects of Leucaena leucocephala ingestion on ringtailed lemurs (Lemur catta) at Berenty Reserve, Madagascar.
abstract: Leucaena (Leucaena leucocephala) is a leguminous tree that is nutritious forage for domestic livestock when ingested in limited amounts. Unfortunately, leucaena contains mimosine, a plant amino acid, that can be toxic when ingested at higher concentrations. Reported toxic effects include alopecia (fur loss), poor body condition, infertility, low birth weight, thyroid gland dysfunction, and organ toxicity. Originally native to Mexico and Central America, leucaena has been introduced throughout the tropics, including Berenty Reserve, Madagascar where it was planted as supplemental browse for livestock. In Berenty, a seasonal syndrome of alopecia in ringtailed lemurs (Lemur catta) is associated with eating leucaena. Although much is known about the toxic effects of leucaena and mimosine on domestic animals and humans, the systemic effects on wildlife had not been studied. In a comparison of lemurs that include leucaena in their diet and those that do not, we found that animals that ingest leucaena absorb mimosine but that ingestion does not affect body condition, cause kidney or liver toxicity, or affect the intestinal tract. Alopecia is due to mimosine's interference of the hair follicle cycle. Leucaena ingestion is associated with higher serum albumin, α-tocopherol, and thyroxine concentrations, suggesting that leucaena may provide some nutritional benefit and that lemurs can detoxify and convert mimosine to a thyroid stimulating metabolite. The primary conservation consequence of leucaena ingestion at Berenty may be increased infant mortality due to the infants' inability cling to their alopecic mothers. The widespread introduction of leucaena throughout the tropics and its rapid spread in secondary forest conditions mean that many other leaf-eating mammals may be including this tree in their diet. Thus, exposure to leucaena should be considered when wildlife health is being evaluated, and the potential effects on wildlife health should be considered when contemplating leucaena introduction into or near wildlife habitat.
authors: San Francisco Zoo Veterinary Department, San Francisco, California.
authors: Graham
authors: G
authors: Crawford
authors: California Animal Health and Food Safety Laboratory System and the Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California.
authors: Birgit
authors: B
authors: Puschner
authors: Department of Anatomic Pathology, School of Veterinary Medicine, University of California, Davis, California.
authors: Verena
authors: V
authors: Affolter
authors: Wildlife Disease Laboratories, Institute for Conservation Research, San Diego Zoo Global, San Diego, California.
authors: Ilse
authors: I
authors: Stalis
authors: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California.
authors: Autumn
authors: A
authors: Davidson
authors: Department of Radiology and Surgical Services, School of Veterinary Medicine, University of California, Davis, California.
authors: Tomas
authors: T
authors: Baker
authors: California Animal Health and Food Safety Laboratory System and the Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California.
authors: John
authors: J
authors: Tahara
authors: Department of Biological and Environmental Science, School of Life Sciences, University of Sussex, Falmer, Brighton, United Kingdom.
authors: Alison
authors: A
authors: Jolly
authors: San Francisco Zoo Veterinary Department, San Francisco, California.
authors: Susan
authors: S
authors: Ostapak
mesh_terms: D000505:Alopecia / Q000139:chemically induced / Q000503:physiopathology / Q000662:veterinary*; D000818:Animals; D004032:Diet / Q000662:veterinary; D007887:Fabaceae / Q000633:toxicity*; D005260:Female; D006197:Hair / Q000503:physiopathology; D007668:Kidney / Q000187:drug effects / Q000473:pathology; D007900:Lemur; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008270:Madagascar; D008297:Male; D008898:Mimosine / Q000378:metabolism / Q000633:toxicity*; D012709:Serum Albumin / Q000378:metabolism; D013974:Thyroxine / Q000097:blood; D024502:alpha-Tocopherol / Q000097:blood
chemical_list: D012709:Serum Albumin; D008898:Mimosine; D024502:alpha-Tocopherol; D013974:Thyroxine
keywords: Madagascar; alopecia; mimosine; toxicity; wildlife