A Body Condition Score for Crocodilians (original) (raw)

Body condition (BC) has been used extensively to evaluate fitness in animals. In traditional studies of crocodiles, the paradigm of evaluating BC with the Fulton index and interpreting the results with quartiles is predominant. However, the wide variety of indices available provides a diversity of tools with which BC can be interpreted in multiple ways. In this study, three indices based on the function of length and weight were evaluated: the Fulton index (K), relative condition index (Kn), and scaled mass index (SMI). The body condition score (BCS) index was also adapted. This was performed as a clinical evaluation of specific morpho-anatomical points. The Fulton index presented a strong relationship with corporal size that generates poor interpretation, scoring low BC in small individuals and high BC in large individuals. This problem does not occur in Kn, SMI nor BCS. SMI and Kn are difficult to interpret, but this is normally conducted by quartiles, generating ambiguous and potentially misleading explanations. The use of BCS avoids these complications because its direct and simple evaluation acts to convert the abstract numbers of the indices to a clinical reality.