Effects of fennel (Foeniculum vulgare L.) on consumption of two Mediterranean Juniperus species by goats

Mediterranean maquis ecosystem is the most important habitat for herbivores and livestock. But forage value of the Medirerranean shrubs varies considerably. Plants possess a variety of flavour and nutritional qualities as well as toxins. Juniperus species, as J. oxycedrus L. and J. phoenice L., are one of the dominant shrubs of Mediterranean maquis and posses a large amount of essential oils. Terpenes and terpenoids are the primary constituents of the 'essential oils' of many species of plant. Herbivores limit intake of plant to minimize the potentiall toxic effect of terpenes. In our experiments, total content of essential oils in shrubs of J. phoenicea was approximately two times higher than in shrubs of J. oxycedrus. We conducted two experiments (5 days each) comparing intake of tested shrubs individually and in combination with fennel (Foeniculum vulgare L.). In both experiments, goats consumed more total shrubs (P<0.01) when fed in conjunction with fennel. In these experiments, total intake of shrubs for both Juniperus species was different. Namely, goats consumed 10 times more J. oxycedrus then J. phoenicea in tested groups and 26 times more in controled ones. Our conclusion is that fennel has positive effect on consumption of terpenes-rich shrubs. However, space diversity, flavor, nutrients and toxins may affect shrubs intake and production. This knowledge will help in better understanding phytocemical interaction between plants and herbivores.