PR - THE EFFECT OF A BYPRODUCT DIET ON THE PERFORMANCE OF DAIRY COWS IN THE UK
The performance of two intensive dairy farming systems is investigated by comparing production, health and financial indicators from continuously housed herds of Holstein Friesian cows. One herd were fed a total mixed ration containing approximately 4.0 tonnes of concentrate and low forage (LF) components. The additional herd were fed solely by-product (BP) feedstuffs which were non-human edible and included no forage components except straw. This by-product and industry waste based ration generated 5% fewer greenhouse gas emissions and required 25% less land. However, the BP diet was more expensive per tonne than the ration containing forage components. Results show this complete by-product diet had negative effects on milk composition which could lead to loss of income for the farmer through penalties for reduced butterfat. Body condition score attributed to the low forage herd was, on average, higher and healthier than the cows consuming by-products. This work suggests that in order to deliver a profitable housed dairy enterprise alongside meaningful emission or land use reductions, trade-offs should be considered and milk quality maintained.
Keywords: dairy system, housed, production, financial, environment