COMPARATIVE EVALUATION OF CLUTCH FREQUENCIES ON EGG PROPERTIES OF FOUR SPECIES OF TORTOISES IN ECOLOGICAL ZONES, NIGERIA

KPEREGBEYI, J. I.; MEYE, J. A.; ONWUMERE-IDOLOR, S. O.; OKHALE, O. E.; NWADIOLU, R.; EWODODHE, A. C. A.

doi:10.70382/mejavs.v9i1.030

Authors

KPEREGBEYI, J. I.

Department of Animal Production, Faculty of Agriculture (FOA), Southern Delta University (SDU), P. M. B. 5, Ozoro, Nigeria.
MEYE, J. A. Department of Animal Production, Faculty of Agriculture (FOA), Southern Delta University (SDU), P. M. B. 5, Ozoro, Nigeria.
ONWUMERE-IDOLOR, S. O. Department of Animal Production, Faculty of Agriculture (FOA), Southern Delta University (SDU), P. M. B. 5, Ozoro, Nigeria.
OKHALE, O. E. Department of Animal Production, Faculty of Agriculture (FOA), Southern Delta University (SDU), P. M. B. 5, Ozoro, Nigeria.
NWADIOLU, R. Department of Agricultural Economics, Faculty of Agriculture (FOA), Southern Delta University (SDU), P. M. B. 5, Ozoro, Nigeria.
EWODODHE, A. C. A. Department of Agricultural Economics, Faculty of Agriculture (FOA), Southern Delta University (SDU), P. M. B. 5, Ozoro, Nigeria.

Abstract

Egg characteristics of tortoise species in ecological zones were observed by traversing line transects to locate nesting females between January to November in 2024–2025. The objective of this study was to evaluate clutch frequencies on egg features of tortoises’ species. Sixty (60) adult tortoises were allocated into 4 groups (Centrochlys sulcata; Pelusios sinuatus; Testudo marginata; and Pelusios castaneus). Clutch size (CLUTS) averaged 6 (range: 4–8) with elliptical, spherical or oval albescent eggs. The mean egg shape index (ESI) ± SD and egg volume (EV) ± SD were 1.16±0.02 and 18.22±1.02 cm³ respectively. Mean Straight Carapace Length (SCL) and egg mass (EM) were 186.00 mm and 2245.50 g respectively. The mean egg length (ELT) and egg width (EWD) ranged from 33.89mm – 38.50mm and 25.29mm – 31.21mm respectively with higher mean values and standard error of 38.50±1.20mm and 31.21 ±0.53mm for P. castaneus and T. marginata respectively. P. sinuatus species had the highest CLUTS of 5 and total egg count of 25 was recorded throughout the seasonal periods of the experiment. The mean relative egg mass (REM), relative clutch mass (RCM), relative egg length (REL), and relative egg width (REW) were calculated as 1.31%, 1.29%, 19.43% and 16.78%, respectively. Differences in clutch frequency of the four tortoise species studied was a significant source of variation in clutch number, CLUTS and total egg production. It is only the P. sinuatus that exhibited significantly different values in all parameters studied.