The WUR team said the results of their research suggested that bromoform can end up in both the milk and the urine of the cow.
FutureFeed, on its website and in emailed comments to this publication, took issue with the study, calling out “the poor animal ethics” involved in the research, with a spokesperson claiming scientific and animal standards were compromised during the WUR led trial.
FutureFeed says it is completely confident in the safety of Asparagopsis when used as recommended based on feed inclusion studies.
The company says it is working with partners to drive adoption of the use of that seaweed species as a feed ingredient for livestock to reduce methane emissions.
Born out of an IP partnership between CSIRO, Meat and Livestock Australia, and James Cook, FutureFeed holds the global IP rights to technology developed by those partners. It has seen investor support from Woolworths, GrainCorp, Harvest Road and AGP Sustainable Real Assets/Sparklabs Cultiv8.
Response to FutureFeed's claims
The lead author on the Dutch study, Wouter Muizelaar, researcher in marine resources for animal nutrition Wageningen University Livestock Research or WUR, defended the study.
Firstly, he said, while seaweed is a promising option to reduce enteric methane production in cattle, not all seaweed species are equally suitable for this purpose. “Many species have been studied (in vitro) for their methane reduction potential, and the Asparagopsis seaweed species showed promising strong reduction in methane reduction of ruminants (both in vitro and in vivo).”
He said the goal of the WUR study, however, was to further examine the potential for transfer of the active compound in the Asparagopsis seaweed species, bromoform, to milk, urine, feces, and animal tissue and to consider the effects on animal welfare and food safety. “For these kind of studies, it is necessary to work with different kind of inclusions rates, ones that not only represent the most likely use-level dose on commercial farms, but those were taken into account as well,” said Muizelaar.
The lead author said he and his colleagues were fully transparent in their paper about the experiment, its development, the results, and interpretations. “The statement from Future Feed (FF) highlights only very specific details and omits other relevant information, leading to a potential misinterpretation of the study results," he told us.
FutureFeed, in its website posting on the WUR study, claimed: “During a four-day feed deprivation regimen, the one milk sample that had detectable levels of bromoform came from only one of the cows receiving the most hazardous concentration of Asparagopsis and that individual [cow] had feed intake on the day of only 3.1kg. Existing research has demonstrated that amount of Asparagopsis should be mixed with 75kg of feed to be at the desired minimum effective intake of Asparagopsis where animal welfare and economics are sustainable. That’s a perilous 24 times higher concentration forced on the Wageningen cows.”
In response, Muizelaar said: “Highlighted in this statement by FutureFeed is the period between day 7-10. Section 3.4 of our paper, about the feeding strategies, shows that on day 7 and day 10, new feeding strategies were adopted. Actually, bromoform was measured in the milk and urine of cows in all treatment groups before and during days 7-10 [as shown in Table 3 of our paper]. Bromoform was present on day 1 in the milk of both the low and medium treatment groups and in the milk of the high treatment group on day 9. In the urine, bromoform was detected in all treatment groups on day 1 and day 10. These facts are not included in FutureFeed’s statement.
“FutureFeed concludes that the feed intake of the animals in the high treatment group was only 3.1kg on day 9 when the sample was taken. This is incorrect [as shown in Table 4 of our paper]. On day 9, the feed intake of cow H1 was actually 7.7 kg dry matter (DM).
“Furthermore, the feed intake on day 9, which is incorrectly referenced as 3.1kg in FutureFeed’s statement, is compared to a feed intake of 75kg per day. However, this 75kg/d mentioned by Future Feed is based on fresh weight, not on dry weight.
“FutureFeed does not provide a DM percentage of this fresh weight, but this would approximately be around 20 kg/d DM basis. Comparing fresh weight with dry weight is the same as comparing apples with oranges.”
Muizelaar added that, based on this specific day and animal, with “wrong reference to the actual feed intake”, FutureFeed concludes that all animals throughout the whole experiment were forced to consume 24x higher concentrations. “This is again incorrect due to the comparing of fresh weight vs dry weight, and, considering all animals throughout the whole study, the average feed intake was much higher than the wrongly cited 3.1kg.”
FutureFeed claimed: “The Wageningen study proves that dairy cows need to be subjected to a state of disregard for animal welfare and forced through feed deprivation to a state of high risk to fatal injury before bromoform can be detected in the milk.”
Muizelaar said this interpretation of the WUR work was also incorrect. “On day 1, bromoform was detected in the milk of low and medium treatment animals. The feed intake of these animals on this day (and the first days after) was not low. Animals in the low and medium treatment group had a rather normal feed intake. Several animals consumed the Asparagopsis and transfer of bromoform to the milk and the urine was detected.”
All the treatment levels were comparable to other studies in this field, he said.
He noted that Roque et al. (2019) used levels of 0.5% and 1.0% (organic matter (OM) basis) of a similar type of seaweed, Asparagopsis armata, with dairy cattle.
“Stefenoni et al. (2021) did not report OM, but we estimated the levels they used with dairy cattle are some 0.15 and 0.30% on OM basis. Our low and medium levels (0.24 and 0.44% OM basis) are similar to these levels, and only the high level (1.34% OM basis) was greater than the levels used in those dairy cattle studies; 1.34% on OM basis is still way lower than the highest level evaluated according to literature, in sheep (3.0% OM) (Li et al., 2016).”
FutureFeed claimed: “Using much more sensitive techniques able to detect much lower levels of bromoform than the Wageningen study, bromoform from Asparagopsis was not detected in meat or milk in any study and the results of multiple studies repeatedly demonstrate the significant impact Asparagopsis can safely have on methane emissions from agriculture – it is a proven performer”
In response, Muizelaar claims that bromoform has been detected in milk in previous studies.
“In a recent US study, Stefenoni et al. (2021) measured bromoform in the milk when using Asparagopsis taxiformis. Compared to the control, the bromoform levels almost doubled (from 16.5 to 28.9 μg/L milk for control and highest level, respectively), but this doubling was not significant due to the large variation [Table 3 in Stefenoni’s paper].
“These levels were comparable to the levels found in our study (when detected, bromoform ranging from 6.2 to 35 μg/L milk). In the study of UC Davis (Roque et al., 2019), the bromoform measured in the milk was 100 times lower than the studies of Penn State and Wageningen, which is inexplicable. In the study of UC Davis, the time of sampling, sample handling and processing for bromoform analysis was not mentioned, making comparison difficult."
In summary, Muizelaar said that any new product must be carefully evaluated, both in terms of its efficacy but also in terms of consumer and animal safety.