Identification of possible nutritional and stress risk factors in the development of marmoset wasting syndrome.

Marmoset wasting syndrome (MWS) describes a series of symptoms in callitrichids that lead to general weakness and a failure to thrive in captive conditions such as zoological institutions. Though the cause of MWS has not been identified, the majority of hypotheses are linked to deficiencies of specific nutrients and increased stress levels. Questionnaires were sent to zoos requesting information on diets and housing of currently living and dead callitrichids before their deaths, as well as their postmortem reports. Risk factors for development and occurrence of MWS include close proximity of predator enclosures and high levels of dietary magnesium and zinc. Variables with effects which may protect against the development of MWS included provision of a nest box, natural trees within enclosure, reduced visibility to visitors, as well as dietary factors such as higher concentrations of potassium and fiber fractions. The protective effects of limited concentrate feeds and increased total dietary fiber may help reduce the risks of developing MWS. The minerals may not have biological implications in MWS per se, however, they may be reflective of diets too high in concentrates and too low in plant matter. Habitat designs that are less naturalistic and those which provide insufficient privacy or hide areas may increase chronic stress for callitrichid species, possibly because of visitor-related stress. Other causes of chronic stress in captive zoo populations should be the topic of further research to reduce occurrence of MWS.

Feeding Asian pangolins: An assessment of current diets fed in institutions worldwide.

Pangolins are ant specialists which are under intense threat from the illegal wildlife trade. Nutrition has notoriously been their downfall in captivity and is still an issue in regards to rescue and rehabilitation. We analyzed the nutrient content of diets used by institutions that are successfully keeping Asian pangolins and to assess the variety of the ingredients and nutrients, compared these with the nutritional requirements of potential nutritional model species. We performed intake studies at five institutions and also had data from three other institutions. We also analyzed five different wild food items to use as a proxy of wild diet. We observed two categories of captive diets: those mostly or completely composed of insects and those high in commercial feeds or animal meat. Nutrient values were broad and there was no clear rule. The non-protein energy to protein energy ratio of the diets were much higher than the wild food items, more so for those which receive less insects. The average contribution of carbohydrate, fat and protein energy were also further away from the wild samples the less insects they contained. The previously suggested nutritional model for pangolins is the domestic dog which is supported by our relatively large nutrient ranges of apparently successful diets, however due to their highly carnivorous nature; the upper most nutrient intake data are not consistent with this and favor the feline nutrient recommendations. We are unable to render a conclusion of what model is more appropriate based on our data collected.

Population size and habitat quality affect genetic diversity and fitness in the clonal herb Cirsium dissectum.

Remaining populations of plant species in fragmented landscapes are threatened by declining habitat quality and reduced genetic diversity, but the interactions of these major factors are rarely studied together for species conservation. In this study, the interactions between population size, habitat quality, genetic diversity and fitness were investigated in 22 populations of the clonal herb Cirsium dissectum throughout the British Isles. Regression analysis was used to identify significant factors, and a structural equation model was developed to illustrate and integrate these interactions. It was found that smaller populations (measured as the total number of plants) had lower genetic diversity (proportion of polymorphic loci), and that reduced genetic diversity (allelic richness) had a negative impact on the survival of seedlings grown under standard conditions. Habitat quality also had a large effect on C. dissectum. Unmanaged sites with tall vegetation, no bare soil and higher nutrient levels had smaller populations of C. dissectum, but flowering was promoted. Flowering was suppressed in heavily grazed sites with short vegetation. Higher levels of bare soil and phosphorus both had a positive relationship with genetic diversity, but probably for distinctly different reasons: bare soil provides safe sites for establishment, whilst phosphorus may promote flowering and improve seed germination. In order to conserve C. dissectum, management needs to maintain site heterogeneity so that C. dissectum can flower and establishment gaps are still available for seedlings; when either component is reduced, negative feedbacks through reduced genetic diversity and individual fitness can be expected. This study therefore highlights the importance of considering both conservation genetics and habitat quality in the conservation of plant species.

BIAZA statistics guidelines: toward a common application of statistical tests for zoo research.

Zoo research presents many statistical challenges, mostly arising from the need to work with small sample sizes. Efforts to overcome these often lead to the misuse of statistics including pseudoreplication, inappropriate pooling, assumption violation or excessive Type II errors because of using tests with low power to avoid assumption violation. To tackle these issues and make some general statistical recommendations for zoo researchers, the Research Group of the British and Irish Association of Zoos and Aquariums (BIAZA) conducted a workshop. Participants included zoo-based researchers, university academics with zoo interests and three statistical experts. The result was a BIAZA publication Zoo Research Guidelines: Statistics for Typical Zoo Datasets (Plowman [2006] Zoo research guidelines: statistics for zoo datasets. London: BIAZA), which provides advice for zoo researchers on study design and analysis to ensure appropriate and rigorous use of statistics. The main recommendations are: (1) that many typical zoo investigations should be conducted as single case/small N randomized designs, analyzed with randomization tests, (2) that when comparing complete time budgets across conditions in behavioral studies, G tests and their derivatives are the most appropriate statistical tests and (3) that in studies involving multiple dependent and independent variables there are usually no satisfactory alternatives to traditional parametric tests and, despite some assumption violations, it is better to use these tests with careful interpretation, than to lose information through not testing at all. The BIAZA guidelines were recommended by American Association of Zoos and Aquariums (AZA) researchers at the AZA Annual Conference in Tampa, FL, September 2006, and are free to download from www.biaza.org.uk.