Blood gases, biochemistry and haematology of Galápagos hawksbill turtles (Eretmochelys imbricata)

Abstract

The hawksbill turtle, Eretmochelys imbricata, is a marine chelonian with a circum-global distribution, but the species is critically endangered and has nearly vanished from the eastern Pacific. Although reference blood parameter intervals have been published for many chelonian species and populations, including nesting Atlantic hawksbills, no such baseline biochemical and blood gas values have been reported for wild Pacific hawksbill turtles. Blood samples were drawn from eight hawksbill turtles captured in near shore foraging locations within the Galápagos archipelago over a period of four sequential years; three of these turtles were recaptured and sampled on multiple occasions. Of the eight sea turtles sampled, five were immature and of unknown sex, and the other three were females. A portable blood analyzer was used to obtain near immediate field results for a suite of blood gas and chemistry parameters. Values affected by temperature were corrected in two ways: (i) with standard formulas and (ii) with auto-corrections made by the portable analyzer. A bench top blood chemistry analyzer was used to measure a series of biochemistry parameters from plasma. Standard laboratory haematology techniques were employed for red and white blood cell counts and to determine haematocrit manually, which was compared to the haematocrit values generated by the portable analyzer. The values reported in this study provide reference data that may be useful in comparisons among populations and in detecting changes in health status among Galápagos sea turtles. The findings might also be helpful in future efforts to demonstrate associations between specific biochemical parameters and disease or environmental disasters.

Venous blood gas and biochemical analysis of wild captured green turtles (Chelonia mydas) and Kemp’s ridley turtles (Lepidochelys kempii) from the Gulf of Mexico

“…Maintaining the environmental conditions necessary for proper functions of the i-STAT analyzer, such as temperature and humidity, were a challenge that was overcome by keeping the equipment in a shaded area and near an ice pack for temperature control. Although pH, pCO 2 , and iCa values were manually corrected for temperature using previously published calculations, the auto-corrected values from the i-STAT were very similar PLOS ONE and clinically acceptable as seen in other studies [13,28]. Hematocrit determined by the i-STAT analyzer may be lower than that determined by conventional centrifugation, so these values should be reviewed cautiously [24,28,42].…”

Blood biochemistry of olive ridley (Lepidochelys olivacea) sea turtles foraging in northern Sinaloa, Mexico

“…We found similar values in parameter as PCV, total protein, albumin, globulin and A/G ratio between our females turtles with healthy olive ridley turtles sampled during the breeding season in Costa Rica [ 44 ]. An increase in the concentration of plasma proteins has been observed when the turtles begin their breeding season [ 11 ]; however, this similarity may be due to the nutritional status of our turtles [ 45 ].…”

Biochemistry and hematology parameters of the San Cristóbal Galápagos tortoise (Chelonoidis chathamensis)

“…Although numerous studies on the ecology, behavior and genetics of Galapagos tortoises have been published, little is known about the health status of these animals. Peripheral blood chemistry and hematology parameters are useful diagnostic tools in health assessment and management in the reptiles ( Geffre et al , 2009 ; Zhang et al , 2011 ; Gibbons et al , 2013 ; Lewbart et al , 2014 ; Muñoz-Pérez et al , 2017 ) and many other taxa. To detect and monitor changes in the health of individuals and populations, it is paramount to determine species-specific normal values for blood parameters of interest.…”