Review: Feeding fodder beet to grazing dairy cows: Is it a paradigm for reduced animal welfare and increased economic and environmental risk?

Abstract

Purpose: This review addresses the potential animal welfare, farm profit, and environmental outcomes when fodder beet is fed to grazing dairy cows. Sources: The information and data included in the review are from peer-reviewed literature. Synthesis: Although large yields (>20 t of DM/ha) and high utilization (90%) of fodder beet (FB) are attractive to farmers, a combination of high establishment costs and low milk yield response may reduce profit margin from growing and feeding FB to dairy cows. The limited milk yield response may be a consequence of subacute acidosis, which reduces ruminal fermentation, feed intake, and milk production. Although FB is a low CP (<10%, DM basis) feed, large crop yields increase stocking density, which may increase nutrient leaching and soil erosion when FB is grazed in situ. Conclusions and Applications: Winter FB feeding programs may reduce animal welfare by causing a chemical imbalance leading to hypophosphatemia, hypocalcemia, hypomagnesemia, ketosis, and hepatic lipidosis, in addition to ruminal acidosis. The information available indicates that a trade-off exists between feeding levels of FB to dairy cows that reduce urinary N excretion but impair animal welfare. The high cost of establishment, variable crop yield, and low milk yield response to FB may limit positive financial outcomes when FB is grown to support lactation. Although the high yield capacity of FB will reduce wintering area and costs, animal welfare costs may be greater than currently realized, and we advise producers to proceed with caution.