Zoo Biology最新文献

Studies on captive individuals are highly informative to behavior of animals that can be difficult to observe in the wild. The Amazon Basin emerald treeboa (Corallus batesii) is a prime example, being both arboreal and nocturnal. The current study aimed to document the basic behavior and foraging style of juvenile C. batesii in logistically simpler captive conditions, by creating an activity budget and analyzing location preferences. Individuals spent the majority of the observations (88.2%) stationary, with 41.8% of their time interpreted as resting postures and 24.3% as hunting postures. Data available on other Corallus spp. suggest that juveniles are relatively active foragers, adopting more ambush strategies later as adults. Thus, C. batesii appears to differ from its best-studied congeners in using a high proportion of ambush strategies as juveniles. Nevertheless, movements between ambush postures were evident and juvenile C. batesii may be better described as a mixed forager. Our results do not support recognizing the juveniles as active foragers as in juveniles of other Corallus spp. Juvenile C. batesii displayed preferences for spatial locations in both resting and foraging behaviors.

The proximate composition of milk from seven free-ranging white rhinoceroses during the first 20 days of lactation is reported with detailed analysis of minerals and fatty acids. The composition of colostrum (day 1) is marked by a high content of dry matter at 23.8 g/100 g milk, mainly consisting of 18.0 g/100 g proteins, 5.6 g/100 g lactose, 0.6 g/100 g fat, 0.7 g/100 ash and 0.2 g/100 g NPN. The major minerals consisted of 24.0 mg/100 g Na, 55.2 mg/100 g K, 33.4 mg/100 g Ca, 10.3 mg/100 g P, 10.1 mg/100 g Mg and 0.4 mg/100 g Zn. The gross energy was 123.2 kCal/100 g. On day 2 the dry matter decreased to 11.9 g/100 g, specifically the ash and protein, and an increase of lactose, Ca and P. The change from colostrum to milk was complete at day two and transitional changes continued to day 5. Changes up to twenty days were minimal with lactose as main component at 6.6 g/100 g, followed by 1.3 g/100 g protein, 1.0 g/100 g fat, 0.2 g/100 g ash, 0.1 g/100 g NPN, 5.6 mg/100 g Na, 15.0 mg/100 g K, 53.3 mg/100 g Ca, 19.9 mg/100 g P and a gross energy of 41.4 kCal/100 g. At days 3 and 4 of lactation the fat content of the rhinoceros milk peaked at 1.6 g/100 g milk. The milk fatty acid composition was characterized by a high saturated content of 68-82%. Capric-, lauric, myristic, and palmitic fatty acids were the major fatty acids, followed by oleic- and linoleic acids. Caprilic- and capric acid, as well as the sum of medium chain fatty acids content, steadily increased to stabilize after day 5. The Δ9-desaturase 16 and -18 indexes reached peak activity at days 2-3 of lactation.

Given the morphological conformation of seahorses, there are several difficulties associated with the evaluation of body reserves and physical condition. This study proposes the development and validation of a body condition scoring system (BCS) applicable to Hippocampus reidi. This study comprises two phases: first, the development of the BCS methodology, followed by its application to a group subjected to an experimental diet, which serves to validate our findings. Weight gain and biometric parameters of 31 seahorses were weekly monitored for a period of 90-150 days. Additionally, histological analysis of organs of the digestive and reproductive tract was carried out to characterize and validate the scoring system, as well as a skin lipid profile evaluation as a measure of lipid mobilization. It is proposed that animals should be evaluated for abdominal muscle coverage, thoracic narrowing, contrast between the dorsal and abdominal region and muscle coverage between dorsal rings. We found significant differences between size and accumulation of fat in the liver as well as the degree of development of the gonads in the animals evaluated. Better energy reserves and reproductive potential are therefore expected for animals with a higher BCS. Our BCS methodology presents itself as an alternative of high practicality, simplicity and low cost, being an innovative tool for the evaluation of energy reserves in Syngnathids.

Good feed management in captivity is essential to animal survival and well-being. For snakes, most studies focus on the frequency of prey consumption and the types of prey that constitute their diets in the wild. Conversely, there is a notable scarcity of studies regarding their dietary habits in captivity. The prevailing trend involves feeding nearly all snake species exclusively with mice, barring the exceptions found in ophiophagic species. Considering that Bothrops species consume different diets in young and adults in the wild, we use B. jararacussu as a model to introduce other prey items in captivity. We use a generalized linear model (GLM) to understand if native and exotic anurans can be alternative items in the captivity diet of young and adult individuals. Our glm showed that snakes fed on bullfrog had less weight gain and consequently less growth than those provided with other diet groups. Our experiments indicated that native anurans could be an interesting food alternative to B. jararacussu and other Bothrops species with an ontogenetic diet in captivity.

Sichuan takins (Budorcas taxicolor tibetana) are capable climbers whose movements in the wild appear to be driven by seasonal variations in resources. Ex situ habitats for takins frequently incorporate elevated features to encourage species-appropriate climbing. We opportunistically observed three takins at the Saint Louis Zoo, split across two adjacent habitats, to quantify their climbing behaviors for 8 months in 2023. One of the males observed was under treatment for arthritis, with additional treatments occurring during the study. Observation sessions were performed several times each day via single 1-min interval scans that recorded elevation status and whether subjects were active, recumbent, or standing still. All takins were observed climbing throughout the study, but repeated measures tests found no significant differences in activity or elevation between months. Takins on elevated structures were less often recorded active when compared to their behavior at ground level, and males were observed more often standing still rather than laying down when elevated compared to the female. The arthritic male was less active and less often observed on elevated structures in his habitat compared to the female and older male, though his activity and climbing seemed to improve after medical interventions that included two rounds of stem cell treatments. Although the sample size was small, this study highlights the importance of planning habitat features relevant to the natural history of species in order to encourage appropriate behaviors.

Birds are kept in captive settings globally, and many of these birds are not flight-restrained. It is generally considered more ethical to house birds in aviaries than to practice flight restraint through wing clipping or pinioning, which means that aviaries are needed to prevent birds from escaping. Traditionally, rectangular aviaries are commonly used; these aviaries may not be well designed for bird flight, especially for large-bodied species. In this paper, we draw attention to the circular flight aviary, a design which has the potential to encourage extended flight in captive birds without the need for excessively large exhibit design. Several circular flight aviaries are already used in select zoos globally, but there is at present, limited empirical evidence on the welfare benefits for birds. We evaluate the tools that are required to assess the effects of circular flight aviary design on bird welfare, with a focus on aspects of exercise physiology that are sometimes overlooked in traditional welfare assessments. The circular design may also be used to overcome challenges associated with breeding birds in complex social structures, such as those which benefit from being housed in large flocks yet are intolerant of other individuals when nesting. Circular flight aviaries, if developed with a view to generating an evidence base, have the potential to improve bird welfare, at a time when bird flight is becoming more restricted globally due to disease implications.

Understanding the factors influencing the likelihood of breeding success is essential to the sustainable management of ex situ populations. Using keeper questionnaires and studbook data, we investigate maternal success in Southern Cheetahs (Acinonyx jubatus jubatus) in relation to life history and husbandry factors. Maternal success was measured using five maternal success indicators: (i) overall litter size; (ii) proportion of liveborn cubs in a litter; (iii) proportion of liveborn cubs raised by their mother surviving the 6-week neonatal stage; (iv) proportion of liveborn cubs raised by their mother surviving to 12 months; and (v) absence of maternal neglect. Cheetahs rep the feeding of ruminant meat and carcasses to cheetahs was found to be significantly related to a larger average litter size while the practice of starve days was associated with a higher stillbirth rate. Females who were moved to new enclosures for the pregnancy, lactation and parenting period also had poorer maternal success. While enrichment provision did not appear to result in a more positive mothering outcome, feederballs and catnip use were associated with lower mothering success, highlighting the importance of evidence-based practice in ex situ collections.

Incubation of pink pigeon (Nesoenas mayeri) eggs under foster doves is an important element of the captive breeding program for this threatened species, and determining optimal species-specific incubation conditions could help to maximize hatchability. We analyzed 7 years of records (n = 104 eggs) from a captive collection to investigate whether the existing guideline for optimal total weight loss of 15% is appropriate for the pink pigeon. Successfully hatched eggs lost on average 14% of their initial mass during incubation, while a weight loss of 15.5% was associated with embryo mortality, and successful eggs lost slightly less weight per day, both as raw weight and as percentage of fresh weight. Eggs weighing at least 14 g at laying were significantly more likely to hatch than lighter eggs, indicating that low fresh weight may be the most useful predictor of embryo death in pink pigeons.

Reliably assessing vitamin D status in nonhuman great apes presents unique challenges, including the optimal collection, handling and storage of appropriate samples, assay selection, and interpretation of results. In recent decades, significant scientific evidence accumulated on these matters in humans, but a comprehensive overview of this topic in nonhuman great apes is currently lacking. This paper provides a review of the various sample types, storage and transport considerations, the wide range of available assays and their respective advantages and disadvantages, as well as important considerations for the reporting and interpretation of results, including environmental and individual animal-related factors. A thorough discussion of the reasons behind inter- and intra-assay variability of vitamin D metabolite concentration measurement is provided with the intent to support those caring for great apes to be able to reliably assess vitamin D status and interpret results. We also highlight the limitations of current human reference intervals, cover the existing literature on nonhuman great apes, and the importance of standardization across institutions to improve animal welfare and facilitate robust research. Finally, we provide a set of recommendations based on primarily current human literature to support zoo and sanctuary practitioners.

Management of African wild dogs (Lycaon pictus) in zoos involves several challenges, including the difficulty of providing appropriate stimulation and enrichment for naturally wide-ranging, energetic, cursorial hunters. Perhaps consequently, zoo packs can exhibit bouts of extreme intra-pack aggression rarely seen in the wild. As with other species, considerable efforts are required to balance the retention and exhibition of wild-type behaviors, against ensuring that the nutritional and welfare needs of individual group-living animals are met. While some behaviors, such as hunting and wide-ranging movements are impossible to mimic in zoos, the provision of food may be refined to allow natural feeding behavior to be displayed. We conducted a feeding experiment on a breeding pack of nine African wild dogs at Taronga Western Plains Zoo in Australia, presenting food in three treatments (individual pieces, butchered carcasses, and whole carcasses) to determine whether: (1) natural age-related patterns of feeding behavior were observed; (2) food type or presentation affected feeding behavior, duration, and interactions. Free-ranging African wild dogs exhibit an age-based feeding structure at kill sites that is rare in other species. We found that carcass and butchered carcass feeds more closely exhibited the age-based feeding observed in the wild. The pack spent twenty times as long consuming carcasses than food presented as individual pieces, with consumption times matching those in the wild. Carcass and butchered carcass feeds also increased the number and rate of interactions over food compared to individual pieces, with a high proportion of interactions resulting in sharing outcomes. This suggests that carcass feeds allow the exhibition of natural patterns of behavior without increasing the risk of negative social interactions. Our results highlight the importance and possibility of managing socially complex carnivores through husbandry that balances the display of natural behavior with positive animal welfare.