Hyperkeratotic mange caused by Sarcoptes scabiei (Acariformes: Sarcoptidae) in juvenile human-habituated mountain gorillas (Gorilla gorilla beringei).

To facilitate ecotourism and behavioral research, free-ranging mountain gorillas (Gorilla gorilla beringei) have been habituated to humans. During routine health monitoring, five juvenile gorillas were observed with active crusted dermatitis and alopecia. Papular and vesicular lesions and crusts with papular eruption and oozing were numerous and disseminated over the body of one gorilla with a confirmed infestation of scabies. In this gorilla, the hyperkeratotic crusts were loose and thick with a flaky and scaly appearance. Histologically, the epidermis was thickened, displayed hyperkeratosis and was infiltrated with lymphocytes and neutrophils. Examination of skin scraping yielded a positive identification of adults and eggs of Sarcoptes scabiei mites. The gorillas were treated with ivermectin, 200 mg kg(-1). As S. scabiei mites can cross-infect various mammalian species causing self-limiting dermatitis, these ectoparasites can be propagated in the habitats shared by gorillas, people, and livestock, and therefore they represent an anthropozoonotic threat.

Field anesthesia of free-living mountain gorillas (Gorilla gorilla beringei) from the Virunga Volcano region, Central Africa.

Twenty-six anesthetic procedures involving 24 free-living mountain gorillas (Gorilla gorilla beringei) from Rwanda or the Democratic Republic of Congo were performed between February 1987 and October 1997. Sixteen procedures were performed to remove snares or to treat snare-related wounds, and four of the animals died without recovering consciousness because of their severe medical conditions. Ketamine was used for induction 19 times, tiletamine/zolazepam was used five times, and the agent was not recorded for two procedures. The mean (+/- SD) ketamine dosage for four animals of known weight was 7.1 +/- 0.9 mg/kg. All induction agents were delivered i.m. by remote injection, and mean induction times for ketamine and tiletamine/zolazepam were 5.5 +/- 2.6 min (n = 12) and 5.4 +/- 3.7 min (n = 5), respectively. Mean recovery times were significantly shorter with ketamine compared with tiletamine/zolazepam (42.0 +/- 24.9 min, n = 9 vs. 75.25 +/- 22.1 min, n = 4). Low hemoglobin oxygen saturation (mean = 86.7%) was recorded in three cases under ketamine anesthesia, and oxygen insufflation is therefore recommended to prevent hypoxemia. Gorillas induced with tiletamine/zolazepam had significantly higher respiratory rates compared with animals given ketamine. Successful anesthesia and recovery, in particular, depended on the assistance of local personnel.

Gastrointestinal parasites of mountain gorillas (Gorilla gorilla beringei) in the Parc National des Volcans, Rwanda.

Ninety-eight fecal samples were collected from 74 free-living mountain gorillas (Gorilla gorilla beringei) from the Parc National des Volcans, Rwanda, between July 1995 and January 1997 and examined for parasites by Sheather's sugar and zinc sulfate flotation methods, trichrome staining, and larval cultures. All samples contained at least one parasite. Seventeen endoparasites were identified, including eight protozoa, seven nematodes, one cestode, and one trematode. Two species of arthropod mite were also recovered from the fecal samples. Parasites observed on fecal examinations included strongyle/trichostrongyle-type eggs (72/74) (representing Oesphagostomum sp., Trichostrongylus sp., Hyostrongylus spp., and possibly Murshidia sp.), Strongyloides sp. (1/74), Trichuris trichiura (2/74), Probstmayria sp. (7/74), Anoplocephala sp. (63/74), Entamoeba hartmanni cysts and trophozoites (19/70), Endolimax nana cysts (31/70), Iodamoeba buetschlii cysts (11/70), Endolimax nana or Iodamoeba buetschlii trophozoites (63/70). Entamoeba coli cysts and trophozoites (14/70), Entamoeba histolytica trophozoite (1/70), Chilomastix sp. cysts and trophozoites (31/70), and Giardia sp. cysts (2/70). In addition, one ascarid and one trematode egg were seen. There were no significant differences in the prevalence of parasites between males and females and between age groups: however, infants and juveniles appeared to have a lower prevalence of Anoplocephala gorillae, and the silverbacked males appeared to have a higher prevalence of Probstmayria sp. Parasite prevalence was consistent among the five social groups studied except Susa group had a significantly lower prevalence of Anoplocephala gorillae. Trichuris trichiura, Strongyloides sp., Chilomastix sp., and Endolimax nana were identified for the first time in this population, and it is possible that these parasites were of human origin. Although there were no obvious clinical effects due to the presence of these parasites, six parasites identified (Trichuris trichiura, Strongyloides sp., Oesphagostomum sp., Trichostrongylus sp., Entamoeba histolytica, and Giardia sp.) could potentially be pathogenic. Some of the parasite products and cultured larvae could not be speciated.

Analysis of urine from free-ranging mountain gorillas (Gorilla gorilla beringei) for normal physiologic values.

Voided urine samples were collected from apparently healthy free-living mountain gorillas (Gorilla gorilla beringei) and analyzed for normal physiologic values. Mountain gorillas were found to have a high urinary pH (x = 8.45) and low specific gravity (x = 1.013). Commercial dipsticks appear to be unreliable for the measurement of specific gravity and leukocytes. The establishment of urinary reference intervals should aid in the noninvasive detection of certain diseases in the mountain gorilla and assist with prompt and effective decisions regarding the immobilization and treatment of individual gorillas.