The variations of oil content and composition of Diplotaenia cachrydifolia Boiss. in green and dry states as a forage anti-quality factor

The essential oil yield and composition of the aerial parts of Diplotaenia cachrydifolia Boiss. were investigated in green and dry states, to understand why it is toxic and unpalatable in green state and palatable in dry state, for livestock. The essential oil was obtained by hydro-distillation method with Clevenger-type apparatus. GC and GC/MS analysis were carried out for investigating the oil composition. According to the results, the oil yield was 2.7% in green state and 0.4% in dry state. Ighteen components were identified representing 91.4% of the oil in green state and 17 components representing 91.6% of the oil in dry state. The major volatile components in green state were: limonene (49.6%), Cis-β-ocimene (12.6%), dill apiole (10.8%) and α-phellandrene (4.32%), respectively and in dry state were: limonene (50.7%), dill apiole (18.3%), Cis-β-ocimene (10.3%) and α-pinene (4.1%), respectively. The results showed that the high amount of the oil in green state is a factor for decreasing plant palatability. Furthermore, β-myrcene and α-phellandrene which are harmful biological compounds decreased in dry state. These compounds are introduced as forage anti-quality factors. In conclusion, the high quantity of volatile oil and some components are forage anti-quality factors.