Giant Anteater (Myrmecophaga tridactyla Linnaeus, 1758) of the brazilian cerrado: Hematology and storage effect

Abstract

Giant Anteater (Myrmecophaga tridactyla) is a vulnerable species because of progressive habitat destruction, mostly affected by wildfires and car accidents. The increasing number of animals that are attended by wildlife rescue centres reinforces the need of knowledge about haematological parameters, especially for those that inhabit Brazilian cerrado biome. For this purpose and in order to establish reference values for this species and also to compare them with previous studies, haematological analysis of captive giant anteaters from Brazilian cerrado were performed. Moreover, the alterations of blood samples after 24 and 48 hours of storage at refrigeration temperatures (4oC) and preserved with two different EDTA concentrations (5% and 10%) were studied. Means and standard deviations of haematological parameters analysed immediately after collection were: RBC: 2,07 ×106/μL ± 0,40; hematocrit: 38,08%± 5,93; haemoglobin: 11.33g/dL±2.15; MCV:186.52 fL±21.72; MCHC: 29.68g/dL±2.56; MCH: 55.08pcg±5,94; total leucocytes: 8.142/μL±2.441; neutrophils: 5.913/μL±2.168; lymphocytes: 1.460/ μL±740; eosinophil: 522/μL±385; monocytes: 247/μL±176; thrombocytes: 123.458/ μL±31.362 and total plasma protein: 6.23g/dL±0.49. This data shows evidence of the existence of important differences between these values and others from other areas, either from Brazil or from other South American countries. Those variations might be connected to environment, genetic, nutritional and/or management factors. Regarding the storage effect analysis, it can be concluded that in giant anteaters, haematological analysis can be performed until 24h after collection without any significant alterations on the haematological parameters, except for thrombocytes. Concerning the different EDTA concentrations, it can be concluded that there are no quantitative differences in haematological variables. Nevertheless, relevant morphologic alterations in blood cells can be observed after a 24h storage period, being most noticeable in the leucocytes. Those alterations can lead to misinterpretation of the results, interfering diagnosis, prognosis and treatment.