No abstract

The effects of B chromosomes in Allium schoenoprasum on germination rate and on the ability of seeds to germinate under drought conditions have been investigated. When water was freely available for germination, there was an increased frequency of B-containing individuals amongst the first 10 per cent of seeds to germinate compared with the middle germinating group (64 cf. 56 per cent). Two drought regimes were employed: in one ('droplet') seeds were provided with a limited amount of water, and in the other ('PEG') the availability of water was limited osmotically. There was a significantly increased frequency of B-containing individuals amongst the 5 per cent of seeds that were able to germinate in both the droplet sample (79 per cent) and the PEG sample (65 per cent) compared with the control sample (56 per cent). Although the early and drought germinating groups had higher frequencies of B-containing seedlings, the individual seedlings did not carry a significantly increased number of B chromosomes. The increases in the frequencies of B-containing seedlings in the early and drought germinating groups were comparable to or greater than that observed previously in the wild between the seed and seedling stages, suggesting that the increased survival of B-containing individuals in natural populations could be due to the effects of Bs on germination behaviour. There was no relationship between the presence of B chromosomes and seed size, seed density or seed shape, implying that differences in these seed characteristics do not provide an explanation of the effects of B chromosomes on germination.

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.

Dung counts are frequently employed to infer abundance of antelope species in African forests, but the accuracy of dung identification has rarely been tested. We used non-invasive genetic methods to test the accuracy of both field identification and morphometrics for identifying dung samples collected in the Udzungwa Mountains, Tanzania. Species identity was established by sequencing part of the mitochondrial control region from faecal DNA. Field identification was found to be correct in only 58-76% of cases depending on the observer. Discriminant analysis of dung pellet length correctly classified 80% of samples but a larger reference sample size is needed before using this method to classify dung of unknown origin. The results of this study illustrate the potential inaccuracy of dung counts as a monitoring tool for sympatric forest antelope species when the probability of correct identification is unknown. We recommend molecular testing of species identity during forest antelope surveys before conclusions are drawn on the basis of other identification methods.

In captivity, the pygmy slow loris Nycticebus pygmaeus population worldwide suffers from poor reproduction, dental diseases, facial abscesses and various other health problems which, cumulatively, mean that the population is far from self-sustaining. The diet recommendations are anecdotal at best, and improvements are urgently needed for this vulnerable species. New evidence suggests that wild N. pygmaeus are primarily exudativores, and consume nectar and gum daily from a variety of tropical plant species, along with a large variety of insects. The typical diet in captivity contains fruit, a concentrated pellet, some insects and occasionally gum as enrichment. Our aims were to compare the behavioural activity budget of 1 male N. pygmaeus at Paignton Zoo on his original diet, on the same diet with added nectar and on an evidence-based naturalistic diet of mainly gum and nectar. We also investigated the nutrient intake of 2 males when given these diets. Behavioural observations were made overnight using night-vision cameras for 15, 10 and 11 d for each diet, respectively. Abnormal (generalised linear mixed model, GLMM χ 2 (1, 2) = 8.673, p = 0.013), travelling (GLMM χ 2 (1, 2) = 6.107, p = 0.047) and feeding (GLMM χ 2 (1, 2) = 79.679, p = 0.0001) behaviours all varied significantly between diets. In the behavioural study, the addition of gum, nectar and insects and the removal of fruit expanded and diversified the loris' activity budget and reduced the extent to which abnormal behaviour patterns were displayed. The intake study showed that both lorises consumed more when fed the naturalistic diet, suggesting they found it more palatable. Evidence of diet change suggests that a naturalistic approach to feeding N. pygmaeus enhances its welfare.KEY WORDS: Loris · Diets · Evidence-based husbandry · Gum · Nectar · Exudativore Resale or republication not permitted without written consent of the publisher Contribution to the Theme Section 'Conservation and ecology of slow lorises'FREE REE ACCESS CCESS