Fluorosis as a probable factor in metabolic bone disease in captive New Zealand native frogs (Leiopelma species).

This report describes the investigations into the cause and treatment of metabolic bone disease (MBD) in captive native New Zealand frogs (Leiopelma spp.) and the role of fluoride in the disease. MBD was diagnosed in Leiopelma archeyi and Leiopelma hochstetteri in 2008 at three institutions: Auckland Zoo, Hamilton Zoo, and the University of Otago. Most of these frogs had originally been held at the University of Canterbury for several years (2000-2004) but some were collected directly from the wild. Radiographs on archived and live frogs showed that MBD had been present at Canterbury, but at a lower rate (3%) than in the current institutions (38-67%). Microcomputed tomography showed that the femoral diaphyses of the captive frogs at Auckland Zoo had greater bone volume, bone surface, cross-sectional thickness, and mean total cross-sectional bone perimeter, which is consistent with osteofluorosis. On histology of the same femurs, there was hyperplasia, periosteal growth, and thickening of trabeculae, which are also consistent with skeletal fluorosis. An increase in fluoride levels in the water supply preceded the rise in the incidence of the above pathology, further supporting the diagnosis of osteofluorosis. Analysis of long-standing husbandry practices showed that ultraviolet B (UVB) exposure and the dietary calcium:phosphorus ratio were deficient when compared with wild conditions-likely causing chronic underlying MBD. To prevent multifactorial MBD in captive Leiopelma, the authors recommend increasing dietary calcium by incorporating into the captive diet inherently calcium-rich invertebrates; increasing exposure to natural or artificial (UVB) light; and using defluoridated water. Addressing these three factors at Auckland Zoo reduced morbidity, bone fractures, and mortality rates.

Chloramphenicol with fluid and electrolyte therapy cures terminally ill green tree frogs (Litoria caerulea) with chytridiomycosis.

Terminal changes in frogs infected with the amphibian fungal pathogen Batrachochytrium dendrobatidis (Bd) include epidermal degeneration leading to inhibited epidermal electrolyte transport, systemic electrolyte disturbances, and asystolic cardiac arrest. There are few reports of successful treatment of chytridiomycosis and none that include curing amphibians with severe disease. Three terminally ill green tree frogs (Litoria caerulea) with heavy Bd infections were cured using a combination of continuous shallow immersion in 20 mg/L chloramphenicol solution for 14 days, parenteral isotonic electrolyte fluid therapy for 6 days, and increased ambient temperature to 28 degrees C for 14 days. All terminally ill frogs recovered rapidly to normal activity levels and appetite within 5 days of commencing treatment. In contrast, five untreated terminally ill L. caerulea with heavy Bd infections died within 24-48 hr of becoming moribund. Subclinical infections in 15 experimentally infected L. caerulea were cured within 28 days by continuous shallow immersion in 20 mg/L chloramphenicol solution without adverse effects. This is the first known report of a clinical treatment protocol for curing terminally ill Bd-infected frogs.

Efficacy of chemical and botanical over-the-counter pediculicides available in Brazil, and off-label treatments, against head lice ex vivo.

BACKGROUND: There is a lack of reliable data on the efficacy of over-the-counter (OTC) pediculicides in Brazil. METHODS: We performed ex vivo assays of eight marketed pediculicides: 1% permethrin (Kwell, Clean Hair, Keltrina, Nedax), 0.02% deltamethrin (Deltacid, Pediderm), and two "natural" products (Piolho e Lêndea, Pilogenio). We also tested 5% permethrin (Keltrina Plus), traditional home remedies and an ivermectin-based product used in veterinary medicine. Head lice (49-52 per group) were immersed in the compound for 3 min and washed after 20 min to simulate the typical in vivo treatment protocol. Lice were examined for activity up to 24 h using stringent criteria for survival. RESULTS: Of the permethrin containing products, highest mortality was observed with Kwell and Clean Hair (97.9 and 90.2% after 4 h). Keltrina, Nedax, Keltrina Plus, and the two deltamethrin-based products showed only a low efficacy of <60% after 4 h. With exception of pure coconut oil (80% mortality after 4 h), home remedies showed a very low efficacy, and both marketed products killed few lice. The ivermectin-based product caused a mortality of 100% after 4 h. CONCLUSIONS: Most Brazilian OTC products did not show a satisfactory efficacy against head lice. Resistance may be present. Ivermectin and coconut oil are promising compounds for topical treatment. Laboratory-based tests should be used to assess resistance patterns and to identify formulations of the active ingredient that increase the efficacy. Standardized testing should be performed before a product is licensed for head lice treatment.

A comparison of botanical and synthetic substances commonly used to prevent head lice (Pediculus humanus var. capitis) infestation.

BACKGROUND: Pediculosis, caused by head lice (Pediculidae: Pediculus humanus var. capitis), is experiencing a global resurgence, with the prevalence in primary schools averaging as high as 40% in some areas regardless of socioeconomic factors. Control efforts using chemical treatments are becoming increasingly ineffective, with insecticide resistance recorded in several countries. Prevention using repellents and oils would be useful if they limited transmission. Many commercially available substances reputedly have effective repellent qualities, but remain untested. METHODS: This study tested the preventative efficacy of N,N-diethyl-3-methylbenzamide (DEET) against several commercially available botanicals to clarify their value as transmission inhibitors, irritants, repellents, and antifeedants. RESULTS: The transfer of head lice to treated hairs was limited by the slippery nature of the oils rather than their repellent qualities. Irritancy was not important because lice proceeded despite being highly irritated, except in the case of coconut. Tea tree and peppermint caused the most repellence, and tea tree and lavender prevented some blood feeding on treated skin. Comparatively, tea tree oil was most efficacious, with DEET ranking equal second overall with coconut, peppermint, and a botanical mixture. CONCLUSIONS: Neither DEET nor any of the botanicals tested showed sufficient preventative efficacy to be endorsed.