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Alison Jolly - One of the best experts on this subject based on the ideXlab platform.
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systemic effects of Leucaena leucocephala ingestion on ringtailed lemurs lemur catta at berenty reserve madagascar
American Journal of Primatology, 2015Co-Authors: Graham C Crawford, Birgit Puschner, Verena K Affolter, Ilse Stalis, Autumn P Davidson, Tomas W Baker, John Tahara, Alison Jolly, Susan OstapakAbstract: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. Am. J. Primatol. 77:633–641, 2015. © 2015 Wiley Periodicals, Inc.
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coat condition of ringtailed lemurs lemur catta at berenty reserve madagascar ii coat and tail alopecia associated with Leucaena leucocepahala 2001 2006
American Journal of Primatology, 2009Co-Authors: Alison JollyAbstract: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.
Scott A. Dalzell - One of the best experts on this subject based on the ideXlab platform.
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effect of tree density on competition between Leucaena leucocephala and chloris gayana using a nelder wheel trial ii belowground interactions
Crop & Pasture Science, 2018Co-Authors: Nahuel A A Pachas, Max H Shelton, Christopher J Lambrides, John G Murtagh, Scott A. Dalzell, Craig HardnerAbstract:Silvopastoral systems with the tree legume Leucaena (Leucaena leucocephala (Lam.) de Wit) and grass pastures are widely used for ruminant feeding in subtropical and tropical regions. Different densities and planting configurations of Leucaena will influence relative yields of both species because of intra- and interspecific competition. With the aim to describe the effects of competition between Leucaena and Rhodes grass (Chloris gayana Kunth), a Nelder Wheel trial with 10 different Leucaena tree densities (100–80 000 trees ha–1) growing with and without Rhodes grass was established in a subtropical environment at Gatton, south-east Queensland, in November 2013. From 2014 to 2016, the biomass of Leucaena (six harvests) and Rhodes grass (seven harvests) was measured by using allometric equations and the BOTANAL sampling procedure over 742 and 721 days, respectively. No complementary or facilitative aboveground interactions were observed between the Leucaena and Rhodes grass components of the pasture system. Increasing Leucaena tree density resulted in greater aboveground intra- and interspecific competition. Average maximum individual tree yield (38.9 kg DM tree–1 year–1) was reached at 100 trees ha–1 without grass competition and was reduced by 60% with grass competition. Rhodes grass biomass yield was negatively affected by shading from the Leucaena canopy, with negligible grass yield at tree densities ≥8618 trees ha–1. Therefore, there was effectively no grass competition on individual tree yield at higher Leucaena densities. Accordingly, edible Leucaena biomass per unit area was positively related to log10 Leucaena density (R2 = 0.99) regardless of grass competition, reaching 21.7 t DM ha–1 year–1 (2014–15) and 27 t DM ha–1 year–1 (2015–16) at the highest Leucaena density of 80 000 trees ha–1. By contrast, the yield of Rhodes grass was linearly and inversely correlated with log10 tree density (R2 = 0.99). Practical implications for the design and management of commercial Leucaena–grass pastures are discussed.
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effect of tree density on competition between Leucaena leucocephala and chloris gayana using a nelder wheel trial ii belowground interactions
Crop & Pasture Science, 2018Co-Authors: Nahuel A A Pachas, Max H Shelton, Christopher J Lambrides, John G Murtagh, Scott A. Dalzell, Craig HardnerAbstract:Leucaena (Leucaena leucocephala (Lam.) de Wit subsp. glabrata (Rose) Zarate) in combination with grass pasture is one of the most persistent, productive and sustainable grazing systems used in Queensland, Australia. Nevertheless, a better understanding of the competitive interactions that determine the proportions of Leucaena and grass components is needed to optimise the design and management of the hedgerow pasture system. In a water-limited environment, belowground interactions between species are especially influential. Accordingly, the aim of this study was to determine the effect of Leucaena plant density and Rhodes grass (Chloris gayana Kunth) competition on root distribution, evapotranspiration, patterns of soil-water use and the resulting water-use efficiency (WUE) of the Leucaena and grass components. Results showed that although Leucaena had deeper roots than Rhodes grass, the majority of fine roots of both Leucaena and Rhodes grass were in the upper 1.5 m of the soil profile suggesting a high level of competition for water resources. A major factor favouring Rhodes grass was that its root abundance was 8–10 times greater than Leucaena, allowing it to compete more effectively for water resources and limit the lateral spread of Leucaena roots. Higher cumulative evapotranspiration values were recorded from Leucaena grown with Rhodes grass than from Leucaena grown in absence of grass. However, this difference was negligible at the highest Leucaena density owing to the reduced yield of grass caused by shading and increased water uptake of Leucaena. The findings of this study also confirmed the hypothesis that at low tree densities, Leucaena–grass pasture will have higher WUE (13.8 kg DM mm–1) than sole Leucaena, but this difference was reduced with increments of Leucaena density. Highest WUE (65.9 kg DM mm–1) occurred at highest Leucaena density with or without grass.
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survey of long term productivity and nutritional status of Leucaena leucocephala grass pastures in subtropical queensland
Animal Production Science, 2016Co-Authors: Max H Shelton, Alejandro Radrizzani, Olena Kravchuk, Scott A. DalzellAbstract:A survey of the productivity and nutritional status of Leucaena (Leucaena leucocephala subsp. glabrata) pastures of different ages was conducted in subtropical Queensland from 2006 to 2008. Four Leucaena stands (aged 8, 20, 31 and 38 years) growing on the same Vertosol soil type at Brian Pastures Research Station were surveyed. In the higher rainfall season of 2007-2008, Leucaena yields and rainfall-use efficiency were highest in 8-year-old stands [2128 kg total dry matter (DM)/ha or 4.0 kg DM/ha.mm] and lowest in 38-year-old stands (978 kg total DM/ha or 1.9 kg DM/ha.mm). The reduced productivity in the 38-year-old Leucaena pasture was associated with a decline in stem number/plant and Leucaena plant density due to observed plant mortality. The reduced yield and vigour of aging Leucaena was associated with nitrogen deficiency related to declining phosphorus and sulfur availability for adequate symbiotic N2 fixation and Leucaena plant growth. Nutrient deficiencies of phosphorus and sulfur in leaf tissue were related to low to medium initial soil fertility (7-27 mg/kg of bicarbonate extractable phosphorus in the top 20 cm), coupled with inherent subsoil constraints (shallow soils, sodicity and high pH), and exacerbated by both long-term removal of nutrients by grazing animals and a reduction in soil phosphorus and sulfur availability over time. To maintain the productivity of Leucaena pastures, plant nutritional status needs to be monitored in order to determine strategic fertiliser application.
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a grazier survey of the long term productivity of Leucaena Leucaena leucocephala grass pastures in queensland
Animal Production Science, 2010Co-Authors: Scott A. Dalzell, Alejandro Radrizzani, Olena Kravchuk, H M SheltonAbstract:Leucaena leucocephala subsp. glabrata (Leucaena)-grass pastures are productive, perennial and long-lived (40 years). However, little is known about changes in the productivity of these pastures as they age even though they are grazed intensively and are rarely fertilised. A postal survey of beef cattle producers in Queensland who grow Leucaena pastures was conducted. The questionnaire gathered information regarding: property location; extent and age of Leucaena pastures; soil type; Leucaena and grass establishment methodology; grazing and fertiliser management; and grazier perceptions of changes over time in Leucaena productivity, grass growth and ground cover, prevalence of undesirable grasses and weeds, and livestock productivity. Graziers were asked to report on both young (≤10 years old) and aging (10 years old) pastures under their management. Eighty-eight graziers responded describing 124 Leucaena paddocks covering 11750 ha. The survey results described the typical physical and management characteristics of Leucaena pastures in Queensland. Graziers reported a decline in Leucaena productivity in 58% of aging pastures, and declines in grass growth (32%) and livestock productivity (42%) associated with declining Leucaena growth. Leucaena decline was greater in soil types of marginal initial fertility, particularly brigalow clay, soft wood scrub, downs and duplex soils. Maintenance fertiliser was not applied to most (98%) Leucaena pastures surveyed despite significant amounts of nutrient removal, particularly phosphorus and sulphur, occurring over prolonged periods of moderate to high grazing pressure. It is predicted that large areas of Leucaena pasture will continue to suffer soil nutrient depletion under current management practices. Research is needed to develop ameliorative actions to reinvigorate pasture productivity. © 2010 CSIRO.
Susan Ostapak - One of the best experts on this subject based on the ideXlab platform.
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systemic effects of Leucaena leucocephala ingestion on ringtailed lemurs lemur catta at berenty reserve madagascar
American Journal of Primatology, 2015Co-Authors: Graham C Crawford, Birgit Puschner, Verena K Affolter, Ilse Stalis, Autumn P Davidson, Tomas W Baker, John Tahara, Alison Jolly, Susan OstapakAbstract: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. Am. J. Primatol. 77:633–641, 2015. © 2015 Wiley Periodicals, Inc.
Graham C Crawford - One of the best experts on this subject based on the ideXlab platform.
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systemic effects of Leucaena leucocephala ingestion on ringtailed lemurs lemur catta at berenty reserve madagascar
American Journal of Primatology, 2015Co-Authors: Graham C Crawford, Birgit Puschner, Verena K Affolter, Ilse Stalis, Autumn P Davidson, Tomas W Baker, John Tahara, Alison Jolly, Susan OstapakAbstract: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. Am. J. Primatol. 77:633–641, 2015. © 2015 Wiley Periodicals, Inc.
Max H Shelton - One of the best experts on this subject based on the ideXlab platform.
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effect of tree density on competition between Leucaena leucocephala and chloris gayana using a nelder wheel trial ii belowground interactions
Crop & Pasture Science, 2018Co-Authors: Nahuel A A Pachas, Max H Shelton, Christopher J Lambrides, John G Murtagh, Scott A. Dalzell, Craig HardnerAbstract:Silvopastoral systems with the tree legume Leucaena (Leucaena leucocephala (Lam.) de Wit) and grass pastures are widely used for ruminant feeding in subtropical and tropical regions. Different densities and planting configurations of Leucaena will influence relative yields of both species because of intra- and interspecific competition. With the aim to describe the effects of competition between Leucaena and Rhodes grass (Chloris gayana Kunth), a Nelder Wheel trial with 10 different Leucaena tree densities (100–80 000 trees ha–1) growing with and without Rhodes grass was established in a subtropical environment at Gatton, south-east Queensland, in November 2013. From 2014 to 2016, the biomass of Leucaena (six harvests) and Rhodes grass (seven harvests) was measured by using allometric equations and the BOTANAL sampling procedure over 742 and 721 days, respectively. No complementary or facilitative aboveground interactions were observed between the Leucaena and Rhodes grass components of the pasture system. Increasing Leucaena tree density resulted in greater aboveground intra- and interspecific competition. Average maximum individual tree yield (38.9 kg DM tree–1 year–1) was reached at 100 trees ha–1 without grass competition and was reduced by 60% with grass competition. Rhodes grass biomass yield was negatively affected by shading from the Leucaena canopy, with negligible grass yield at tree densities ≥8618 trees ha–1. Therefore, there was effectively no grass competition on individual tree yield at higher Leucaena densities. Accordingly, edible Leucaena biomass per unit area was positively related to log10 Leucaena density (R2 = 0.99) regardless of grass competition, reaching 21.7 t DM ha–1 year–1 (2014–15) and 27 t DM ha–1 year–1 (2015–16) at the highest Leucaena density of 80 000 trees ha–1. By contrast, the yield of Rhodes grass was linearly and inversely correlated with log10 tree density (R2 = 0.99). Practical implications for the design and management of commercial Leucaena–grass pastures are discussed.
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effect of tree density on competition between Leucaena leucocephala and chloris gayana using a nelder wheel trial ii belowground interactions
Crop & Pasture Science, 2018Co-Authors: Nahuel A A Pachas, Max H Shelton, Christopher J Lambrides, John G Murtagh, Scott A. Dalzell, Craig HardnerAbstract:Leucaena (Leucaena leucocephala (Lam.) de Wit subsp. glabrata (Rose) Zarate) in combination with grass pasture is one of the most persistent, productive and sustainable grazing systems used in Queensland, Australia. Nevertheless, a better understanding of the competitive interactions that determine the proportions of Leucaena and grass components is needed to optimise the design and management of the hedgerow pasture system. In a water-limited environment, belowground interactions between species are especially influential. Accordingly, the aim of this study was to determine the effect of Leucaena plant density and Rhodes grass (Chloris gayana Kunth) competition on root distribution, evapotranspiration, patterns of soil-water use and the resulting water-use efficiency (WUE) of the Leucaena and grass components. Results showed that although Leucaena had deeper roots than Rhodes grass, the majority of fine roots of both Leucaena and Rhodes grass were in the upper 1.5 m of the soil profile suggesting a high level of competition for water resources. A major factor favouring Rhodes grass was that its root abundance was 8–10 times greater than Leucaena, allowing it to compete more effectively for water resources and limit the lateral spread of Leucaena roots. Higher cumulative evapotranspiration values were recorded from Leucaena grown with Rhodes grass than from Leucaena grown in absence of grass. However, this difference was negligible at the highest Leucaena density owing to the reduced yield of grass caused by shading and increased water uptake of Leucaena. The findings of this study also confirmed the hypothesis that at low tree densities, Leucaena–grass pasture will have higher WUE (13.8 kg DM mm–1) than sole Leucaena, but this difference was reduced with increments of Leucaena density. Highest WUE (65.9 kg DM mm–1) occurred at highest Leucaena density with or without grass.
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survey of long term productivity and nutritional status of Leucaena leucocephala grass pastures in subtropical queensland
Animal Production Science, 2016Co-Authors: Max H Shelton, Alejandro Radrizzani, Olena Kravchuk, Scott A. DalzellAbstract:A survey of the productivity and nutritional status of Leucaena (Leucaena leucocephala subsp. glabrata) pastures of different ages was conducted in subtropical Queensland from 2006 to 2008. Four Leucaena stands (aged 8, 20, 31 and 38 years) growing on the same Vertosol soil type at Brian Pastures Research Station were surveyed. In the higher rainfall season of 2007-2008, Leucaena yields and rainfall-use efficiency were highest in 8-year-old stands [2128 kg total dry matter (DM)/ha or 4.0 kg DM/ha.mm] and lowest in 38-year-old stands (978 kg total DM/ha or 1.9 kg DM/ha.mm). The reduced productivity in the 38-year-old Leucaena pasture was associated with a decline in stem number/plant and Leucaena plant density due to observed plant mortality. The reduced yield and vigour of aging Leucaena was associated with nitrogen deficiency related to declining phosphorus and sulfur availability for adequate symbiotic N2 fixation and Leucaena plant growth. Nutrient deficiencies of phosphorus and sulfur in leaf tissue were related to low to medium initial soil fertility (7-27 mg/kg of bicarbonate extractable phosphorus in the top 20 cm), coupled with inherent subsoil constraints (shallow soils, sodicity and high pH), and exacerbated by both long-term removal of nutrients by grazing animals and a reduction in soil phosphorus and sulfur availability over time. To maintain the productivity of Leucaena pastures, plant nutritional status needs to be monitored in order to determine strategic fertiliser application.