Guidelines for the interpretation of laboratory findings in birds and mammals with unknown reference ranges: plasma biochemistry.

The results of analyses of plasma samples from healthy and sick adult birds and mammals of a wide range of species were used to calculate reference ranges and clinical ranges for 11 biochemical variables (calcium, sodium, chloride, total protein, albumin, globulin, inorganic phosphate, potassium, bicarbonate, urea and creatinine concentrations) in six mammalian Orders (Primata, Carnivora, Pinnipedia, Proboscidea, Perissodactyla and Artiodactyla) and six avian Orders (Ciconiiformes, Gruiformes, Pelecaniformes, Psittaciformes, Falconiformes and Strigiformes). The patterns of variation between Orders for the different biochemical variables were then used to provide guidelines for the interpretation of plasma biochemistry results in the species in these Orders for which there are no reference data. The observed clinical ranges provide an indication of the potential diagnostic value of each variable.

Aspects of rabies infection and control in the conservation of the African wild dog (Lycaon pictus) in the Serengeti region, Tanzania.

Lycaon pictus is amongst the most endangered wildlife species in Africa. In 1990 rabies virus was isolated from the brain of an adult Lycaon found dead in the Serengeti region of Tanzania. One adult and six pups of the same pack feeding on the carcass showed clinical signs and rabies was suspected; within two days they had disappeared and are presumed to have died. Subsequently, two Lycaon packs in the Serengeti National Park were given inactivated rabies vaccine either by dart or by parenteral inoculation following anaesthesia. Lycaon sera which had been collected over the previous two years and sera collected pre- and post-vaccination were examined for the presence of rabies virus neutralizing antibody. Three of 12 unvaccinated Lycaon had antibody levels > 0.5 IU/ml; post-vaccination samples from two Lycaon showed increased antibody levels. Between four and ten months post-vaccination, at least four of the vaccinated animals had died from unknown causes. Issues relating to wildlife vaccination and veterinary intervention in conservation are discussed.

Rabies in African wild dogs (Lycaon pictus) in the Serengeti region, Tanzania.

Rabies was confirmed as the cause of death of one African wild dog (Lycaon pictus) in the Serengeti region, Tanzania. One adult African wild dog in the same pack showed central nervous signs consistent with rabies infection. Inactivated rabies vaccine was administered intramuscularly to African wild dogs in two packs, by dart or by hand following anesthesia. These individuals comprised all known adults in the Serengeti National Park. In a limited study of seroprevalence of rabies antibody carried out at the time of vaccination, 3 of 12 African wild dogs sampled in the Serengeti had rabies serum neutralizing antibody titers before vaccination. Paired serum samples from two individuals sampled after vaccination showed increased antibody titers.

Development of LYNX: a computer application for disease diagnosis and health monitoring in wild mammals, birds and reptiles.

IBM-compatible software has been developed so that quantitative and qualitative haematological and biochemical reference data for over 500 species of mammals, birds and reptiles can be made readily accessible to veterinary surgeons. The LYNX software makes it possible to retrieve these data at different taxonomic levels (species, genera, families, orders and classes) and to select data by age and sex. The data for each variable may be presented in the form of a reference range or as a frequency histogram. Notes describing the variations in blood cell morphology observed in healthy individuals of each species are included in the database. The user's own haematological and biochemical data can also be entered, stored and used.

Erythrocyte size, number and haemoglobin content in vertebrates.

Relationships between erythrocyte number, size and haemoglobin content were examined in 441 species (101 families) of mammals, birds and reptiles. Whereas the total number of red cells (RBC), the mean cell volume (MCV) and mean cell haemoglobin (MCH) showed much variation, the haemoglobin level (Hb), packed cell volume (PCV) and mean cell haemoglobin concentration (MCHC) were relatively constant in all adult mammals and birds but lower in reptiles. There was a strong positive correlation between MCV and MCH and a strong negative correlation between MCV and RBC across all species. Mammals had more, smaller erythrocytes per unit volume of blood than birds, which, in their turn, had more, smaller erythrocytes than reptiles. The findings confirm that the oxygen-carrying capacity of the blood is highly conserved in birds and mammals but is lower in exothermic groups such as reptiles. Although the significance of the observed species differences in RBC and MCV has yet to be explained, the findings have considerable evolutionary, physiological and diagnostic interest.