© Rory Harper
New insights into dietary management of polar bears (Ursus maritimus) and brown bears (U. arctos) (Robbins et al., 2021)
New paper in Zoo Biology looked into the diets of polar bears & brown bears:
✔Both wild & captive bears select diets with low protein and higher fat or digestible carbohydrate concentration;
✔Captive bears are often fed high-protein diets, which may be associated with their susceptibility to renal failure & liver cancer;
✔Diets of captive polar & brown bears should be reviewed to better match their preferred macronutrients ratios.
Colony composition and nutrient analysis of Polyrhachis dives ants, a natural prey of the Chinese pangolin (Manis pentadactyla) (Xu et al., 2021)
A study in Zoo Biology analysed the nutritional contents & composition of a colony of Polyrhachis dives ants - key prey in the diet of the critically endangered Chinese pangolin:
✔Colony consisted mostly of adults, but also pupae, larvae & eggs;
✔High protein & chitin, low fat & formic acid identified in both colony & adult ants;
✔Colony & adult ants differed in several aspects of chemical composition - diet of captive pangolins shouldn't be composed solely by adult ants as they prey on all colony in the wild;
✔Applications to husbandry and nutrition of captive Chinese pangolins.
Investigating food preference in zoo-housed meerkats
(Brox et al., 2021)
A study in Zoo Biology looked into food preferences in zoo-housed meerkats:
✔Clear, stable preference hierarchy identified;
✔High in preference hierarchy: Cooked eggs & raw meat;
✔Lower in preference hierarchy: Vegetables;
✔Slight differences between juveniles & adults;
✔Applications to zoo management and welfare assessments.
A modified diet to support conservation of the Atala hairstreak butterfly (Eumaeus atala Poey)(Braatz et al., 2021)
A study in Zoo Biology investigated the suitability of a freeze-dried diet in a captive breeding programme for the Atala hairstreak butterfly:
✔Smaller larvae fed freeze-dried leaves & stems from host plant;
✔Larger larvae switched to live-plant diet;
✔Highly successful method: over 3400 individuals released into the wild;
✔Freeze-dried diet is appropriate substitute when live plant is scarce or not available - potential applications to other butterfly species.
Ensiling of maple leaves and its use in winter nutrition of mantled guereza (Colobus guereza) (Lasek et al., 2021)
A paper in Zoo Biology evaluated the composition and nutritional value of maple leaf silage and its suitability for inclusion in the winter diets of captive mantled guerezas:
✔Most nutrients were unaffected by ensiling process;
✔Mantled guerezas promptly fed on maple leaf silage.
✔Higher nutrient intake when maple leaf silage included in diet;
✔Ensiling, with or without additives, effectively conserved maple leaves.
Grading fecal consistency in an omnivorous carnivore, the brown bear: Abandoning the concept of uniform feces (De Cuyper et al., 2021)
A study in Zoo Biology graded faecal consistency in nine zoo-housed brown bears fed a variety of diets:
✔Six-point scale established for uniform faeces;
✔Additional grading system for faeces with dual consistencies (observed in 11% of all faeces);
✔More vegetation or whole prey seemed to be associated with firmer faeces;
✔Faecal consistency is affected by diet in this species and can be used for gut health monitoring.
Circulating nutrients and hematological parameters in managed African elephants (Loxodonta Africana) over a 1‐year period (Wood et al., 2020)
A study published in Zoo Biology investigated the circulating nutrients and hematological parameters in zoo-housed African elephants, over a one-year period:
✔Seasonal changes in circulating nutrients;
✔African elephants fed mixed feedstuff & fortified pellet diets may not need Vitamin E supplementation.
✔Assessment of circulating nutrients provides evidence for better elephant management in captivity.
Daily lettuce supplements promote foraging behavior and modify the gut microbiota in captive frugivores (Greene et al., 2020).
A study in Zoo Biology investigated the effects of daily lettuce supplements on the behaviour and gut microbiota of captive ruffed lemurs:
✔The lemurs (especially younger individuals) consistently foraged on the lettuce during the study period;
✔Enrichment of potentially-beneficial microbes in the guts;
✔Lettuce provision is potentially beneficial to captive frugivores.
Dietary management of hypercholesterolemia in a bachelor group of zoo-housed Slender-tailed meerkats (Suricata suricatta) (Dobbs et al., 2020)
Captive meerkats are prone to high cholesterol levels, which can lead to health problems. A study in JZAR investigated the impact of a new diet on cholesterol levels in a group of zoo-housed meerkats:
✔New diet with lower saturated fat & cholesterol implemented;
✔Reduction of cholesterol levels in all individual meerkats;
✔Good body condition score & weight reported after new diet introduction.
Photo credit: Twycross Zoo