TRYPTAMINE LEVELS IN PASTURAGE IMPLICATED IN BOVINE PULMONARY EMPHYSEMA

Pasture mediated bovine pulmonary emphysema (BPE) in British Columbia may be associated with high tryptamine levels in aftermath pasture following hay on wetland meadows. Reed canary grass (Phalaris arundinacea L.) (RCG) is the most common component of the BPE meadows containing tryptamines. Tryptamines in this species occur primarily in young chlorophyllous tissue but not in appreciable quantity in root, stem or older leaves; moreover tryptamines disappear with the advent of sharp frost at which time BPE vanishes. Ammonium source fertilizer, especially when applied at high rates, but not nitrate source fertilizer, is associated with high tryptamine levels in RCG Animal trials to confirm involvement of RCG and tryptamines in BPE appear to be warranted.