## 4 Discussion  
We aimed to study the main features of nest composition of wild rabbits and to test if such features are still preferred in naive domestic does. The European rabbit is an especially useful mammalian model for studying maternal behaviour [38] as both wild animals and domestic stocks are available, and the domestication of this species has not dramatically changed the features of maternal behaviour [17; 39; 40]. A well-constructed nest may increase the survival of the offspring and provide long-term benefits to the mother in the wild but is seemingly less important under controlled laboratory settings [36; 41]. Remarkable specialization in the physiological mechanisms underlying the above reactions is known for this species [42; 43]. Mimicking the ancestral situation in the rearing is still plausible [41] and can improve the welfare status of rabbits [44]. The worldwide distribution of rabbits [45] indicates that it is an adaptable species with high phenotypic plasticity enabling it to cope with the challenges in various local habitats. As the vegetation is completely different in the several continents the rabbit inhabits today, both food and nest material choice should be flexible. Diet composition of these animals should change both locally and seasonally [46; 47] to follow food availability. Laboratory data show that the food preferences are fine-tuned by both individual learning and social impacts on diet choice [48] fulfilling the dietary needs of rabbits. Lagomorphs prefer grass species as food wherever these are available [47; 49], but grass is also used for nest building, even by domestic females observed in semi-natural habitats [32; 50]. The high percent of dry grass found in the field nests could have been explained by the ageing of the material, as  
Figure 3: The relative percentage of time spent in collecting from either long (30 cm) or short (10 cm) grass by rabbit females (N = 7). Asterisks indicate significant differences (\(p<0.05\)) in Wilcoxon matched-pairs signed-ranks tests. we have probably found the nests already empty thus being at least 21 days old, when the doe leaves the entrance open and the kits hide outside [18]. Our repeated tests performed mimicking natural conditions indicate that even though there was a significant increase in dry grass scores (see Figure 2), its small dimension suggests that the nests collected in the field should have been predominantly dry at the time of construction. We have found a remarkably small variation in the composition of both the wild rabbit nests and the laboratory constructed nests suggesting that rabbit nest building is a result of tightly controlled mechanisms [43; 51]. While our tests were restricted to the beginning of the nest building, and the plant components are usually collected during several days preceding the parturition [51], we were able to demonstrate that even the initial plant choice indicates clear preferences toward features present in wild rabbit nests. In order to judge the preference in the two-way choice tests, we reduced the time available for nest material collection to one hour as initial observation indicated this period is enough for the does to reduce one bunch of material to minimum. Extending the test period might have resulted in also collecting the inferior material, even though the offered amount of grass was enough to construct a full nest. It would be interesting to follow the process during the several days preceding parturition [51]. The result of Experiment 2 is in accordance with the hypothesis that rabbit does can modify the nest composition by eating out some of the grass disproportionally, as the slight preference to dry grass in the collection phase was found to be significantly enhanced in the final nest composition. Nevertheless, there are other possible explanations of this increase in the dry grass ratio, for example, the time spent collecting is not a reliable measurement of the amount actually collected.