Niche partitioning and competition between different rabbit breeds using stable isotopes

Stable isotope analysis (SIA) is an evolving method for determining diet, understanding food web and resolving biogeochemical issues in the ecosystem. This study aims to trace out ecological niche preferences/partitioning and competition among the lagomorphs, including two different breeds of European rabbit (Oryctolagus cuniculus), New Zealand rabbit and American Dutch rabbit, using SIA. Thirty-two samples of tooth enamel were analysed, which were collected from different districts of Punjab, Pakistan, including Okara, Sahiwal and Kasur. Among these samples, 16 belonged to the New Zealand breed (08 male and 08 female rabbits) and 16 to the American Dutch breed (08 male and 08 female rabbits). Significant (P<0.001) intergender differences in the isotope content of delta C-13 in the enamel for New Zealand and American Dutch rabbit were found. The European rabbits showed significant differences for both genders in the stable isotope of oxygen in the enamel (delta O-18) values (P=0.05). Nitrogen stable isotope results showed no significant intergender differences between American Dutch and New Zealand rabbits (P=0.24). The stable isotope results for delta C-13, delta N-15, and delta O-18 indicate that the trophic niche partitioning of both breeds overlaps, which can potentially cause competition for resources, whereas the water intake may differ among different genders, which may reflect differential gender-related activities. The archaeological and fossilised data of lagomorphs is present, but there is no significant literature available for living lagomorphs (rabbits). In general, this study provides a basic and first dataset for delta C-13, delta N-15, and delta O-18 of living lagomorphs, which can serve as a comparative dataset for future studies.