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1.
Am J Primatol ; 77(6): 633-41, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25809223

RESUMO

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.


Assuntos
Alopecia/veterinária , Fabaceae/toxicidade , Lemur , Mimosina/toxicidade , Alopecia/induzido quimicamente , Alopecia/fisiopatologia , Animais , Dieta/veterinária , Feminino , Cabelo/fisiopatologia , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Madagáscar , Masculino , Mimosina/metabolismo , Albumina Sérica/metabolismo , Tiroxina/sangue , alfa-Tocoferol/sangue
2.
Am J Primatol ; 72(5): 391-406, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20039330

RESUMO

Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island-continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascar's geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10-15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher-training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long-term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Lemur , Animais , Criança , Conservação dos Recursos Naturais/economia , Humanos , Madagáscar , Organizações , População Rural , Instituições Acadêmicas
3.
Am J Primatol ; 71(3): 199-205, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19051314

RESUMO

Fur condition in wild ringtailed lemurs, Lemur catta, was recorded during September-November birth seasons 2001-2006 at Berenty Reserve, Madagascar. Body coat condition was scored on a scale from BS 0: full, smooth coat with guard hairs, to BS5: half or more of back and limbs hairless. Tail condition was scored from TS 0: full, to TS 5: half or more hairless. Where troop core areas included stands of Leucaena leucocephala, alopecia was dramatically more frequent than in similar areas without leucaena, including many animals with score BS5 or TS5, "bald lemur syndrome." Females' coats were worse than males', possibly related to female dominance and access to this preferred food. Tails in non-leucaena-feeding females tend to remain full, even if coats deteriorate, but with leucaena-feeding female tails are highly correlated with coat condition and equally bare. Coat and tail condition in L. catta reflected not only the dietary toxin but individual differences as well as differences between adjacent troops that may result from territorially mediated access to the environment. Leucaena contains the non-protein amino acid mimosine, a known cause of alopecia, wasting, and organ damage in livestock, although the effects are usually reversible. This is the first case of its effect in wildlife. Leucaena is an agroforestry tree introduced throughout the tropics. In high dietary concentrations leucaena might potentially affect any browsing mammal.


Assuntos
Alopecia/veterinária , Fabaceae/química , Cabelo/fisiopatologia , Lemur , Mimosina/efeitos adversos , Cauda , Alopecia/induzido quimicamente , Alopecia/fisiopatologia , Animais , Dieta , Meio Ambiente , Fabaceae/crescimento & desenvolvimento , Feminino , Indicadores Básicos de Saúde , Madagáscar , Masculino , Fatores Sexuais
4.
Am J Primatol ; 71(3): 191-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19051320

RESUMO

An index of coat condition can be a non-invasive tool for tracking health and stress at population level. Coat condition in ringtailed lemurs, Lemur catta, was recorded during September-November birth seasons of 1996, 1997, 1999, and 2001-2006 at Berenty Reserve, Madagascar. Condition was scored on a scale from 0: full, fluffy coat with guard hairs present, to 5: half or more of body hairless. Adult males did not differ overall from adult females. Coats were worse in adults than in 2-year-old subadults; 1-year-old juveniles were intermediate. Mothers and adult males lost coat condition as the season progressed: non-mother females maintained condition. Years 1999-2002 scored better coats than either 1996-1997 or 2003-2006. Lemurs in high population density areas had worse coats than in natural forest, but tourist presence had less effect than density. Monitoring coat condition in an apparently healthy population reveals differences between population segments, and in a forest fragment with limited immigration or emigration it can track progressive changes, correcting impressions of progressive improvement or degradation over time. Above all it gives a baseline for response to climate changes or eventual pathology.


Assuntos
Cabelo/fisiologia , Indicadores Básicos de Saúde , Lemur/fisiologia , Fatores Etários , Envelhecimento , Alopecia/fisiopatologia , Alopecia/veterinária , Animais , Meio Ambiente , Feminino , Madagáscar , Masculino , Mães , Densidade Demográfica , Estações do Ano , Fatores Sexuais , Estresse Fisiológico
5.
Am J Primatol ; 71(3): 183-90, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19142988

RESUMO

Coat condition can be influenced by a wide variety of disorders and thus provides a useful tool for noninvasive health and welfare assessments in wild and captive animals. Using Lemur catta as an exemplar, we offer a 6-step scoring system for coat and tail condition, ranging from perfectly fluffy to half or more of body and tail being hairless. The categories are described in detail and illustrated with sample pictures from a wild population in Berenty Reserve, Madagascar. Furthermore, we elaborate on intermediate conditions and discoloration of fur. Coat condition scoring allows the comparison between years, seasons, and the effect of toxin, disease or stress. Although this system was developed for wild L. catta, we believe it can also be of value for other species. We recommend scoring coat condition in healthy wild mammal populations to give a baseline on yearly and seasonal variations vs. deteriorating health conditions or pathology.


Assuntos
Cabelo/fisiologia , Indicadores Básicos de Saúde , Lemur/fisiologia , Cauda , Alopecia/fisiopatologia , Alopecia/veterinária , Animais , Cor de Cabelo/fisiologia , Nível de Saúde , Estações do Ano
6.
Science ; 309(5740): 1457, 2005 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-16141032
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