A new study in Zoo Biology described the effects of fecal microbiota transplants on the microbiome of a two-toed sloth exhibiting abnormal bowel movements:
✔Microbiome showed positive changes in diversity, composition and membership (more closely resembling the healthy donor's).
✔Pronounced improvement in the bowel movements, although it was temporary.
✔Fecal microbiota transplants can help improving gut microbiome & health.

A zoo-housed giraffe was trained for voluntary foot radiographs when she started displaying signs of lameness, with the training process described in a paper in the Journal of Zoological and Botanical Gardens:
✔Procedure: Positive reinforcement in a protected contact set up.
✔Giraffe was taught six behaviours: (1) Target Training, (2) Recall, (3) Back Up, (4) Station, (5) Lift Foot, (6) Front Foot Radiograph.
✔Radiographs achieved used for clinical evaluation.
✔Training for medical procedures is an effective method to reduce stress & other risks associated.

A study in Zoo Biology looked into contraception of dwarf bucks via immunisation against gonadotropin-releasing hormone (GnRH):
✔Comparison of single immunisation of Improvac (two doses) VS repeated immunisation (one dose every six months); 
✔Males in repeated immunisation group: greater decrease in scrotal circumference, testosterone, male odor & sperm quality.
✔Repeated Improvac treatment reduced BUT did not completely block fertility. 
✔Applications to ex situ contraception & population management.

A paper in Journal of Zoo Aquarium Research investigated current practices in surveilling endotheliotropic herpesvirus shedding in European herds of captive Asian elephants:
✔42% of breeding institutions had protocols for EEHV screening;
✔30% monitored viral shedding;
✔Shedding data (2,863 samples from 12 institutions): 13.9% of samples & 48.9% of elephants tested positive for EEHV;
✔Evidence of EEHV present in all 12 herds;
✔Routine monitoring of EEHV is recommended.

A new paper in Scientific Reports has looked into the vitamin D status of chimpanzees in human care:
✔245 samples from chimpanzees housed at 32 European zoos.
✔Inadequate vitamin D levels detected in 33.1% of samples.
✔Season of the year, health status & daily outdoor access had significant effect on vitamin D status.
✔These inadequate levels can lead to several diseases.
✔Husbandry & nutrition practices for this species must be reviewed & adjusted.

The new issue of Journal of Zoo & Aquarium Research is out, featuring the Mauritian pink pigeon on the cover... This species is also featured in one of the papers, with a disease risk analysis of a translocation of pigeons from the European ex situ programme (EEP) to the captive breeding colony in Mauritius, to increase the genetic diversity there:
✔21 pathogens were medium or high risk to the pink pigeon population.
✔Some were also a risk to poultry & endemic birds.
✔Pre-export quarantine protocol & mitigation techniques developed to reduce risk.
✔On top of 30-day quarantine, multiple testing recommended (e.g. blood samples, radiography, faecal sampling, cloacal swabbing, etc.).
✔Protocol also has applications to future translocations.

A paper in Zoo Biology investigated what factors influence fertility (i.e. testosterone production) in zoo-housed African elephant bulls:
✔Physiology: Glucose-to-insulin ratio (+) associated with testosterone;
✔Physical: Musth score & moderate exercise (+) associated with testosterone (which was lower in overweight elephants);
✔Social: Social contact & female interactions increased testosterone;
✔Management: Time spent outdoors & browse opportunities increased testosterone.

A study in JZAR looked into age and growth of zoo-housed zebra sharks:
✔  288 biometric measurements from 24 individuals;
✔  Average length & weight at birth were 26.5 cm & 71.94 g, respectively;
✔  Accelerated growth in first 3.5 years of life;
✔  No differences in growth between males & females;
✔  Strong correlation between length & weight.

A study in Journal of Zoo Aquarium Research reviewed medical records of 161 Livingstone's bats housed at two zoos between 1992 and 2017:
✔ Most common causes of morbidity: wounds, localised inflammation & fractures;
✔ Males & immature individuals more likely to suffer wounds;
✔ Females more likely to suffer fractures;
✔ Most common causes of mortality: early foetal death, heart diseases & conspecific aggression.

A study in Zoo Biology compared body mass & growth rates of chimpanzees housed at zoos, sanctuaries & research facilities:
✔ Higher body mass in adult zoo & research chimps;
✔ Slower growth rates in sanctuary chimps;
✔ Older age at maturation (body mass) for sanctuary chimps;
✔ Growth patterns of chimps differ between captive environments.

A paper in Zoo Biology compared body condition in captive and wild American alligators:
✔209 captive & 935 wild alligators;
✔Higher body condition in adult captive alligators (weight gain in males);
✔No differences found between juvenile captive & wild individuals;
✔Movement & diet likely played a role in differences detected in adult individuals.

A study in Journal of Zoo & Aquarium Research looked into the behaviour of a zoo-housed meerkat group after the dominant female was implanted with a deslorelin contraceptive:
✔  No births - effective reproductive control;
✔  Social hierarchy and relationships remained stable;
✔  Agonistic behaviours decreased;
✔  12 months later: follicles detected in ovaries - return to reproductive activity?  
✔  Further research on long-term effects recommended.

Does castration affect the development and appearance of captive blackback gorillas? A study in Journal of Zoo & Aquarium Research found:
✔ No significant differences in morphological measures between castrated & intact males;
✔ Lower average weight in castrated males than intact ones, & similar to females;
✔ Lack of sagittal ridge development & secondary sexual traits in castrated males.

A paper in Nature investigated cancer risk across mammalian taxa, using data from zoo-housed mammals (110,148 individuals, 191 species):

✔Carnivorous mammals have highest cancer-related mortality (especially mammal-consuming ones);

✔Cancer mortality risk is independent of body mass & adult life expectancy;

✔Important findings to help the understanding of the evolution of cancer resistance while highlighting the importance of data generated from zoo animals.

A paper in Reproduction & Fertility looked into pregnancy loss & fetal development in zoo-housed red pandas:

✔Trans-abdominal ultrasound examinations on 6 females over 10-year period - 12 profiles;

✔Pregnancy identified in 10 profiles, with 40% of those showing fetal loss;

✔Pregnancy loss (no cubs produced) in 20% of cases, partial loss (one cub lost, one born) in other 20% of cases.

✔Fetal loss between days 51 & 23 pre-partum;

✔Fetal growth characteristics reported - applications to breeding management of this species in captivity.

A paper in Zoo Biology compared post-ovulatory characteristics in a giant panda during a pseudopregnancy (2014) and a pregnancy (2015) at Toronto Zoo:
✔Pseudopregnancy: minimal pre-partum behaviours, unusual uterine edemas & folding, extended luteal phase;
✔Pregnancy: increased feeding time with rise in primary progestagen, followed by a decrease in appetite and activity, and pre-partum behaviours (changes started 25 days before birth);
✔Monitoring behaviour, morphology & urinary-endocrine profiles may facilitate distrinction between pregnancies & pseudopregnancies in giant pandas.

A paper in JZAR described the effectiveness of biosecurity measures (gloves, designated tools or a combination of both) in reducing pathogen transfer in terrarium management:
✔Combination of tools & gloves significantly reduced contamination;
✔The use of gloves or tools alone did not significantly decrease contamination;
✔The combined use of simple biosecurity measures can drastically reduce risk of pathogen transfer in reptile & amphibian captive populations.

Paper in Zoo Biology discussed the applications of Improvest® (GnRH immunological product) in suppressing reproduction in seven captive female giraffes:

✔Ovarian activity stopped in all treated females, reducing male interest & pursuit of females;

✔Supplemental contraception did not reduce effectiveness of Improvest®;

✔Reversible: Treatment stopped 1.5 years later & ovarian activity resumed 90 days after that;

✔Small sample size but interesting applications to captive management of giraffes.

An image-based Body Condition Score (BCS) has been developed for giraffes and published in JZAR:
✔BCS developed for both shoulder & hip areas (rib area not useful for BCS);
✔Score applied & validated in both free-ranging & zoo-housed giraffes;
✔Low scores should be avoided in zoo-housed giraffes but no evidence that high scores are detrimental;
✔On average, higher scores in zoo-housed animals improvements in zoo diets & less restrictions than in the wild.

A study in Zoo Biology looked into data from the International Tiger Studbook to investigate reproductive parameters and survival in the captive tiger population:

✔Low adult mortality & progressive increase of mortality rates after 10 years of age (longevity: 19 years).

✔Females: highest reproductive parameters (litter size and cub survival) when 7-9 years old;

✔Differences found between sub-species, highlighting the importance of considering them separately.

New research looked into body fat, metabolism and activity levels of Asian elephants in nine North American zoos:

✔Higher body fat not associated with abnormal reproductive cycles;

✔Walking rates similar to those of wild individuals;

✔Higher insulin levels in individuals with higher body fat;

✔Threshold for "obesity" in this species was attempted but further research required;

✔Obesity may not be such a problem in this species but may cause metabolic perturbations.

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Photo credit: Smithsonian's National Zoo

The endotheliotropic herpesvirus-haemorrhagic disease (EEHV-HD) is a major cause of death in captive Asian elephants and increasingly recognised in their wild counterparts as well. A risk factor analysis of this disease in Europe (1985-2017) found the following:

✔EEHV-HD accounted for 57% of Asian elephant deaths;

✔Median age of EEHV-HD deaths: 2.6 years;

✔Similar risk for ♂ & ♀ ;

✔Only significant risk factor identified was a previous EEHV-HD death in the institution;

✔Exposure to new elephants was not a significant risk factor.

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Photo credit: Copenhagen Zoo

Heart disease is a major cause of mortality in zoo-housed great apes. A study in Zoo Biology introduced a electrocardiogram technology that facilitates the monitoring of great ape heart health:
✔Kardiamobile allows for voluntary, instant, reliable & economic electrocardiogram readings;
✔Operant conditioning training guidelines provided;
✔System generates evidence to inform management regarding great ape heart health.

New research looked into "lumpy jaw" disease in captive macropods:
✔High mortality (62.5% for Australian & European institutions);
✔Risk of developing the disease increased with age;
✔Different incidence rates & risk of infection between institutions and geographic regions;
✔Recommendations to reduce disease risk were provided.

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Photo credit: Perth Zoo