Growth performance and feed intake behaviour of whey fed beef cattle on an alpine pasture

In alpine-cheese production areas, whey represents an important source of available energy which is both largely untapped and problematic for the environment if it is not properly disposed of. Its utilisation by beef cattle was studied in two trials, each comprising 48 heifers and steers belonging to different breeds or crosses of beef breeds, and allocated to three experimental treatments: a control treatment with access to pasture grass only and two treatments receiving a supplement to grazing, either barley or warm non-centrifuged whey distributed once daily by group in a limited quantity (2012) or ad libitum (2013). The three groups, each comprising 16 animals with an average live weight of 480kg, were summer-grazed in the Jura at an altitude of 1200 m for 95 days. When provided ad libitum, the whey was consumed at the rate of 32.9 litres per animal and per day, and significantly increased the daily weight gain compared to the animals receiving no supplement with no negative effect on carcass quality or health, but with a 60% reduction in water requirement. In conclusion, this production system turns out to be a promising alternative enabling value-added to be given to a by-product such as whey.