Problems with using weight versus carapace length relationships to assess tortoise health
Jacobson, E.R.; Weinstein, M.; Berry, K.; Hardenbrook, B.; Tomlinson, C.; Freitas, D.
Veterinary Record 132(9): 222-223
1993
ISSN/ISBN: 0042-4900 PMID: 8451815 Document Number: 411072
Bodyweight (w) versus carapace length at the midline (MCL) for 40 clinically healthy wild desert tortoises (Gopherus agassizii) were compared to the data for 37 wild desert tortoises with clinical respiratory tract disease. A small but significant difference was found between the log W: log MCL regression lines for the 2 groups but no significant difference was found when slopes of the lines were compared. On average, tortoises with clinical signs weighed about 7% less than the healthy tortoises but several sick tortoises weighed more for their length when compared with healthy tortoises. Factors limiting the usefulness of weight versus carapace length relationships for predicting the health of desert tortoises are discussed. Other methods of assessing health or reproductive potential including history, physical examination, radiography and haematological and biochemical tests should also be considered.