Safety of standardized Macleaya cordata extract in an eighty‐four‐day dietary study in dairy cows
Macleaya cordata (Willd.) R. Br. is a plant (commonly referred to as the plume poppy) native to temperate eastern Asia (China and Japan) (European Food Safety Authority, 2005). The absolute, extract, oil and tincture of the Macleaya cordata plant are listed in the EU feed additive register (European Food Safety Authority, 2015); the extract has been used in several feeding trials of different animal species (Kantas, Papatsiros, Tassis, Athanasiou, & Tzika, 2015; Kosina et al., 2004; Zhang, Wu, Sun, & Liu, 2013). Quaternary benzo[c]phenanthridine alkaloids (QBAs) from Macleaya cordata have been identified as a source of flavouring compounds (Chin, 2009) which could potentially improve palatability of animal feed, similar to several other phytogenic compounds (Yang, Chowdhury, Huo, & Gong, 2015). MCEP, a standardized product of MCE containing the QBAs sanguinarine and chelerythrine, is patented for use as a flavouring agent for animal feeds (Roth, 2003, 2010).
MCE has been reported to be well tolerated when fed to poultry, swine, ewes and steers (Aguilar‐Hernandez et al., 2016; Kosina et al., 2004; Matulka, von Alvensleben, & Morlacchini, 2014). To our knowledge, no prior study describing the feeding of MCE to dairy cows has been reported. The objective of the current study was to assess the safety of Macleaya cordata Extract Product (MCEP) fed to dairy cows (1,000 and 10,000 mg per animal per day), with comprehensive examinations on animal physiology and performance including the milk component as well as haematological and biochemical analyses. The doses in this study reflect the maximum intended amount to be added to cattle feed (1,000 mg/animal) and used in target animal studies based on previous experiences of feeding commercial livestock animals of various species with MCEP/MCE as published in different studies (Aguilar‐Hernandez et al., 2016; Estrada‐Angulo et al., 2016; Juskiewicz et al., 2010; Kantas et al., 2015; Kosina et al.,2004; Matulka et al., 2014), as well as a 10‐fold level above the maximum intended dosage, to access potential adverse effects from accidental excess addition to the feed.