Reply to: Estimating low-opportunity-cost feed

Abstract

replying to Y. Gong and Y. Yang Nature Food https://doi.org/10.1038/s43016-025-01116-z (2025)

We are pleased that Gong and Yang¹ consider our work² an important contribution for alleviating the multiple environmental stresses caused by the global expansion of animal production and its associated increased demand for animal feed^3,4,5. Our study² revealed that the pressures on land use and the environment can be reduced by about one-third in China when partially replacing commercial feed with low-opportunity-cost feeds (LCFs) in animal production. However, Gong and Yang¹ comment that this result may be overestimated because of the use of simple methods, overestimation of the use of food waste and fish meal as animal feed, use of relatively low feed conversion ratios (FCRs) and other possible alternatives for using LCFs. Here we reply to the criticisms and underscore the validity of our estimates.