40 research outputs found

    Parrots Eat Nutritious Foods despite Toxins

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    Generalist herbivores are challenged not only by the low nitrogen and high indigestibility of their plant foods, but also by physical and chemical defenses of plants. This study investigated the foods of wild parrots in the Peruvian Amazon and asked whether these foods contain dietary components that are limiting for generalist herbivores (protein, lipids, minerals) and in what quantity; whether parrots chose foods based on nutrient content; and whether parrots avoid plants that are chemically defended.We made 224 field observations of free-ranging parrots of 17 species in 8 genera foraging on 102 species of trees in an undisturbed tropical rainforest, in two dry seasons (July-August 1992-1993) and one wet season (January-February1994). We performed laboratory analyses of parts of plants eaten and not eaten by parrots and brine shrimp assays of toxicity as a proxy for vertebrates. Parrots ate seeds, fruits, flowers, leaves, bark, and insect larvae, but up to 70% of their diet comprised seeds of many species of tropical trees, in various stages of ripeness. Plant parts eaten by parrots were rich in protein, lipid, and essential minerals, as well as potentially toxic chemicals. Seeds were higher than other plant materials in protein and lipid and lower in fiber. Large macaws of three species ate foods higher in protein and lipids and lower in fiber compared to plant parts available but not eaten. Macaws ate foods that were lower in phenolic compounds than foods they avoided. Nevertheless, foods eaten by macaws contained measurable levels of toxicity. Macaws did not appear to make dietary selections based on mineral content.Parrots represent a remarkable example of a generalist herbivore that consumes seeds destructively despite plant chemical defenses. With the ability to eat toxic foods, rainforest-dwelling parrots exploited a diversity of nutritious foods, even in the dry season when food was scarce for other frugivores and granivores

    Effect of scattered-site housing using rent supplements and intensive case management on housing stability among homeless adults with mental illness: A randomized trial

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    IMPORTANCE Scattered-site housing with Intensive Case Management (ICM) may be an appropriate and less-costly option for homeless adults with mental illness who do not require the treatment intensity of Assertive Community Treatment. OBJECTIVE To examine the effect of scattered-site housing with ICM services on housing stability and generic quality of life among homeless adults with mental illness and moderate support needs for mental health services. DESIGN, SETTING, AND PARTICIPANTS The At Home/Chez Soi projectwas an unblinded, randomized trial. From October 2009 to July 2011, participants (N = 1198) were recruited in 4 Canadian cities (Vancouver, Winnipeg, Toronto, and Montreal), randomized to the intervention group (n = 689) or usual care group (n = 509), and followed up for 24 months. INTERVENTIONS The intervention consisted of scattered-site housing (using rent supplements) and off-site ICM services. The usual care group had access to existing housing and support services in their communities. MAIN OUTCOMES AND MEASURES The primary outcome was the percentage of days stably housed during the 24-month period following randomization. The secondary outcome was generic quality of life, assessed by a EuroQoL 5 Dimensions (EQ-5D) health questionnaire. RESULTS During the 24 months after randomization, the adjusted percentage of days stably housedwas higher among the intervention group than the usual care group, although adjusted mean differences varied across sites. The mean change in EQ-5D score from baseline to 24 months among the intervention group was not statistically different from the usual care group (60.5 [95%CI, 58.6 to 62.5] at baseline and 67.2 [95%CI, 65.2 to 69.1] at 24 months for the intervention group vs 62.1 [95% CI, 59.9 to 64.4] at baseline and 68.6 [95%CI, 66.3 to 71.0] at 24 months for the usual care group, difference in mean changes, 0.10 [95%CI, −2.92 to 3.13], P=.95). CONCLUSIONS AND RELEVANCE Among homeless adults with mental illness in 4 Canadian cities, scattered site housing with ICM services compared with usual access to existing housing and community services resulted in increased housing stability over 24 months, but did not improve generic quality of life.This research has been made possible through a financial contribution from Health Canada
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