ABSTRACT
Over 23 months, zinc toxicosis was diagnosed in 35 baboons aged 5-12 months in one galvanized metal and concrete cage complex with conditions that led to excessive exposure to environmental zinc. Clinical signs included reduced pigmentation of hair, skin, and mucous membranes (whiteness), alopecia, dehydration, emaciation, cachexia, dermatitis, diarrhea and, in six cases, severe gangrenous dermatitis of extremities. The syndrome was characterized by pancytopenia, elevated zinc and low copper serum concentrations, low vitamin D and bone-specific alkaline phosphatase levels, and atypical myelomonocytic proliferation of bone marrow. This syndrome emphasizes the importance of proper husbandry and cage design and indicates the potential of infant baboons as a model to study the effects of excessive zinc on development. This is the first report describing the epidemiologic and clinical presentation of zinc toxicosis in infant baboons in captivity.
Subject(s)
Environmental Exposure , Housing, Animal , Monkey Diseases/pathology , Papio , Vitamin D/analogs & derivatives , Zinc/poisoning , Alopecia/etiology , Alopecia/veterinary , Analysis of Variance , Anemia/etiology , Anemia/veterinary , Animals , Bone and Bones/diagnostic imaging , Copper/blood , Copper/deficiency , DNA-Binding Proteins/blood , Dermatitis/etiology , Dermatitis/veterinary , Diarrhea/etiology , Diarrhea/veterinary , Flow Cytometry/veterinary , Karyotyping/veterinary , Light , PAX5 Transcription Factor , Pigmentation/drug effects , Radiography , Radioimmunoassay/veterinary , Syndrome , Transcription Factors/blood , Vitamin D/blood , Zinc/bloodABSTRACT
Heavy metals are essential for the normal progression of maternal and fetal tissue growth and metabolism in pregnancy. Considerable data have been collected for concentrations of various elements in pregnant women, but no comprehensive evaluation of element concentrations in any non-human primate model has been performed. Baboons were studied at the second half of pregnancy. Forty essential and toxic element concentrations were analyzed by absorption spectrophotometry in paired maternal and fetal blood samples; hair and nail samples in pregnant baboons; in placenta, amniotic fluid; and fetal femur, lymph nodes, and liver. Concentrations demonstrated an excellent correlation with concentrations reported in late human pregnancy. Twenty-four elements were below detectable limits in various specimens. We conclude that the pregnant baboon offers unique opportunities to study both normal maternal, fetal, and placental physiology as well as the environmental toxicology of these elements. This information and the ability to use the pregnant baboon as a model is important because essential and toxic elements are key components of the diet as well as major products of manufacturing processes within our industrialized society.
