The physiological consequences of ingesting a toxic plant (Diplotaxis tenuifolia) and medicinal supplements influence subsequent foraging decisions by sheep.

VILLALBA, J J; CATANESE, F; DISTEL, R

Salt Lake City, UT

Congreso; 2016 Joint Annual Meeting ASAS & ADSA; 2016

ASAS y ADSA

There is a large group of highly nutritious plants which are commonly avoided by grazing livestock due to the presence of toxic plant secondary compounds. Our hypothesis was that aversion towards toxic plants is learned and that their negative post-ingestive effects could be attenuated by specific nutrients. Thus, we determined the impact of supplements on physiological parameters and feeding behavior in Merino sheep consuming Diplotaxis tenuifolia (?Wild rocket?), a plant with high concentration of glucosinolates (37.2±3.6 umol/g). Thirty-six sheep were randomly assigned to four feeding treatments (n=9): Wild rocket (?DT?), Wild rocket and a protein (160 g/d) supplement (?DT+P?), Wild rocket, and a protein supplement containing iodine (10 mg/d) and copper (40 mg/d) (?DT+P+M?), or alfalfa pellets (?CTRL?) in amounts that paired the ingestion of Wild rocket in DT. Towards the end of a 35 d exposure period, sheep in DT showed the lowest intake of Wild rocket (P=0.04), as well as reduced concentrations of plasma thyroid hormones (T3 and T4; P