E J Flach

Batrachochytrium dendrobatidis infection and lethal chytridiomycosis in caecilian amphibians (Gymnophiona)

Batrachochytrium dendrobatidis (Bd) is commonly termed the ‘amphibian chytrid fungus’ but thus far has been documented to be a pathogen of only batrachian amphibians (anurans and caudatans). It is not proven to infect the limbless, generally poorly known, and mostly soil-dwelling caecilians (Gymnophiona). We conducted the largest qPCR survey of Bd in caecilians to date, for more than 200 field-swabbed specimens from five countries in Africa and South America, representing nearly 20 species, 12 genera, and 8 families. Positive results were recovered for 58 specimens from Tanzania and Cameroon (4 families, 6 genera, 6+ species). Quantities of Bd were not exceptionally high, with genomic equivalent (GE) values of 0.052–17.339. In addition, we report the first evidence of lethal chytridiomycosis in caecilians. Mortality in captive (wild-caught, commercial pet trade) Geotrypetes seraphini was associated with GE scores similar to those we detected for field-swabbed, wild animals.

Macromineral Absorption in the Black Rhinoceros (Diceros bicornis) Compared with the Domestic Horse

*Division of Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, Switzerland; yInstitute of Animal Physiology, Physiological Chemistry and Animal Nutrition, Ludwig-Maximilians-University Munich, Oberschleissheim, Germany; **GSF National Research Center for Environment and Health, Institute for Ecological Chemistry, Neuherberg, Germany; zSaint Louis Zoo, St. Louis, MO; yyZoological Society of London, Whipsnade Wild Animal Park, Dunstable, UK; Zoological Garden of Cologne, Cologne, Germany; Institute for Zoo and Wildlife Research (IZW), Berlin, Germany; and Institute of Animal Sciences, Department of Nutrition, University of Bonn, Germany

Positive Skin and Serologic Test Results of Diagnostic Assays for Bovine Tuberculosis and Subsequent Isolation of Mycobacterium interjectum in a Pygmy Hippopotamus (Hexaprotodon liberiensis)

Abstract A 20-yr-old male pygmy hippopotamus (Hexaprotodon liberiensis), weighing 250 kg, arrived at Zoological Society London Whipsnade Zoo (United Kingdom) from a captive collection in Portugal. A quarantine health check was performed including a comparative intradermal tuberculosis (IDTB) test. Assessment of the comparative IDTB test at 72 hr revealed a strong positive reaction at the bovine site. Serum was tested with a rapid immunochromatographic assay (TB STAT-PAK®) and was positive for tuberculosis antibodies. The tuberculosis tests were repeated 6 wk later with the same positive test outcome. In addition, a broncho-alveolar lavage (BAL) was submitted for mycobacterial culture. The positive IDTB test and TB STAT-PAK® results were supported by multiantigen print immunoassay (MAPIA). Based on these results, the animal was suspected to be infected with Mycobacterium tuberculosis complex organisms and was euthanized. No gross or histologic signs of tuberculosis were found at postmortem examination. Mycobacterium interjectum was cultured from the BAL but not from necropsy samples. The antigens used in the TB STAT-PAK® and MAPIA tests are reportedly specific for the M. tuberculosis complex, and so it is possible this animal presented with a latent case of tuberculosis or had a previous tuberculosis infection that resolved prior to testing. Cross-reactions with nontuberculous mycobacteria have been described with TB STAT-PAK® and MAPIA tests. However, Western blotting analysis using serum from this animal did not recognize M. interjectum proteins of equivalent size to the M. tuberculosis-Mycobacterium bovis proteins recognized in the MAPIA. Thus, antigenic cross-reactivity with M. interjectum can be deemed less likely, but other nontuberculous mycobacterial proteins cannot be ruled out. It is therefore possible that false-positive reactions were obtained. These results highlight the difficulty of diagnosing tuberculosis in the absence of pathology and the presence of nontuberculous mycobacteria.

Fatty acid status in captive and free‐ranging black rhinoceroses (Diceros bicornis)*

The fatty acid (FA) patterns of plasma/serum triglycerides (TG), phospholipids (PL) and cholesteryl esters (CE) of captive and free-ranging black rhinoceroses (Diceros bicornis) were investigated. Free-ranging animals (n = 28) stemmed from four different regions. Captive animals sampled included specimens from North American (n = 11) and three different European facilities (n = 6). The European animals were tested on 1-4 different diets, resulting in a total of 15 blood samples. Regardless of differences between the free-ranging animals from different regions, differences between captive and free-ranging animals were relatively uniform: captive animals had higher overall proportions of polyunsaturated fatty acid (PUFA), due to levels of linoleic acid (LA, 18:2n6) that were drastically increased as compared to free-ranging animals. In contrast, levels of alpha-linolenic acid (ALA, 18:3n3) were consistently lower on conventional zoo diets. n6/n3 ratios for TG, PL and CE were 1.6, 10 and 8 in samples from free-ranging animals, respectively, as compared to 4.1-16.3, 16-148 and 40-277 in samples from captive animals. There was a distinct correlation between the proportion of grain-based products (commercial concentrates, plain grains and bread) in the diets of the European animals and the measured levels of n6 PUFA. An animal from a facility with a very low proportion of grain products in the diet nevertheless had high LA readings, most probably due to the use of sunflower oil as 2% (dry matter basis) of its diet. One animal that received a high proportion of grass meal pellets due to an oral disease had increased ALA contents after the diet change. These results allow conclusions on the suitability of diets fed in captivity: the black rhinoceros is prone to several uncommon diseases that have been suspected to be linked to oxidative damage, possibly due to the disposition of this species to excessive iron storage. An unnatural dietary loading with PUFAs would exacerbate this problem. Additionally, n6 FAs are known as precursors of pro-inflammatory mediators, and their overrepresentation could therefore exacerbate any inflammatory processes. Therefore, the current practice of using grain-based feeds as major ingredients in captive rhinoceros diets is discouraged. Diet items containing ALA (a precursor of anti-inflammatory mediators) such as, fresh grass, fresh browse, the respective silages should be included at higher levels in diets for captive black rhinoceroses. Grass meal pellets, although a good source of ALA and linked with high levels of ALA in an animal of this study, must be chosen with care for black rhinoceroses due to their particular proneness for high iron contents.

Quantification of enterobacteriaceae in faeces of captive black rhinoceros (Diceros bicornis) in relation to dietary tannin supplementation

Free-ranging browsing herbivores ingest a range of secondary plant compounds, such as tannins, with their natural diet. As many of these substances have been shown to have antibacterial properties, it could be speculated that a lack of such compounds in captive zoo diets could favour the growth of potentially pathogenic intestinal bacteria. The effect of a supplementation of a conventional diet (N, consisting mainly of grass hay and/or lucerne hay and pelleted compound feeds) fed to eight captive black rhinoceroses (Diceros bicornis) from three zoological institutions with either tannic acid (T), a source of hydrolysable tannins, or quebracho (Q), a source of condensed tannins, was investigated. The number of faecal colony forming units (CFU) of Enterobactericeae was determined by colony count of dilution series from fresh faeces applied to MacConkey agar plates. Tannins were added to the diets at approximately 5-15 g/kg dry matter, depending on the varying intake of roughage and compound feeds by the animals. There was no difference in the number of CFU between diets N (95.0 x 10(5) +/- 225.3 x 10(5)/g fresh faeces) and T (164.3 x 10(5) +/- 225.1 x 10(5)/g fresh faeces); in contrast, diet Q led to a significant reduction in CFU (4.3 x 10(5) +/- 6.5 x 10(5)/g fresh faeces) compared with the other diets. These findings suggest that condensed tannins could have the potential to reduce the number of potentially pathogenic intestinal bacteria, and that the deliberate inclusion of tannin sources in the diets of captive wild animals should be further investigated. The fact that tannic acid, shown to have antibacterial effects in various in vitro studies, did not have an effect in this study, emphasizes that the relevance of tannin supplementation for intestinal health must be verified in vivo.

Alpaca and llama nematodes in Britain

SIR, — Parasites have a significant impact on the health and productivity of South American camelids and, of all the parasites, nematodes have been reported to have the single biggest impact, particularly in animals under one year of age ([Leguia 1991][1]). In their native South America,

A novel investigation of a blister-like syndrome in aquarium echinopora lamellosa

This study investigates potential causes of a novel blister-like syndrome in the plating coral Echinopora lamellosa. Visual inspections of this novel coral syndrome showed no obvious signs of macroparasites and the blisters themselves manifested as fluid-filled sacs on the surface of the coral, which rose from the coenosarc between the coral polyps. Histological analysis of the blisters showed that there was no associated necrosis with the epidermal or gastrodermal tissues. The only difference between blistered areas and apparently healthy tissues was the presence of proliferated growth (possible mucosal cell hyperplasia) directly at the blister interface (area between where the edge of the blister joined apparently healthy tissue). No bacterial aggregates were identified in any histological samples, nor any sign of tissue necrosis identified. We conclude, that the blister formations are not apparently caused by a specific microbial infection, but instead may be the result of irritation following growth anomalies of the epidermis. However, future work should be conducted to search for other potential casual agents, including viruses.

Development of a body condition score for the mountain chicken frog (Leptodactylus fallax)

The Critically Endangered mountain chicken frog (Leptodactylus fallax) has undergone drastic population decline due to habitat loss, hunting, invasive species, and chytridiomycosis. In response, several partner institutions initiated a conservation breeding program. It is important to maintain the captive population in good health. Therefore the program partners have recommended establishment of protocols for health examination of the species, including body condition assessment. Visual body condition scoring is a useful means to assess body condition in zoo animals for which regular bodyweight measurements are impractical or associated with capture-related stress. In this study, the authors developed a visual body condition score for the mountain chicken frog based on an ordinal categorical scale from 1 to 5 (1 = lowest body condition, 5 = highest body condition) using anatomical features that vary with total body energy reserves. Veterinary staff, animal managers, keepers, researchers, and students subsequently used the body condition score to assign scores to 98 mountain chicken frogs (41 male, 57 female) aged between 8 months and 12 years housed in five zoos in the UK and Jersey between February and March 2016. Body condition scores showed moderate (rho = 0.54; males) to strong (rho = 0.6; females) correlation with the scaled mass index, an objective measure of total energy reserves. The majority of pairwise comparisons between scores showed slight to substantial intra-observer agreement (93.8%) and slight to almost perfect inter-observer agreement (97.2%). Cases of poor agreement were likely due to limited observer experience working with the species.

OSTEOCHONDROSIS IN THE DISTAL FEMURS OF AN ADULT RETICULATED GIRAFFE (GIRAFFA CAMELOPARDALIS RETICULATA): MACROSCOPIC, RADIOLOGIC, AND HISTOLOGIC FINDINGS

Abstract An adult male reticulated giraffe (Giraffa camelopardalis reticulata) was presented for postmortem examination. During radiologic examination of the hindlimbs, osseous cyst-like lesions were detected in both medial femoral condyles. These lesions were subsequently examined macroscopically and histologically. The gross appearance suggested a diagnosis of bilateral osteochondrosis that was confirmed with histopathologic examination. This finding has not previously been reported in giraffes. Macroscopic visualization of the major limb joints, including the femorotibial joints, is therefore encouraged in future postmortem examinations of giraffes (Giraffa camelopardalis), and further assessment of clinical significance is required.