| Traditionally, veal calves were fattened on a diet exclusively consisting of milk replacer. Calves fed in this manner consistently showed a range of serious behavioural and health problems. To improve the welfare of veal calves, provision of some solid feed is compulsory in the European Union as of 1997. In addition to animal welfare considerations, there is also a considerable economic incentive to increase the provision of solid feed to veal calves. With increasing prices of milk replacer ingredients, roughage may represent an economically viable substitute for part of the milk replacer. However, observations both in practice and under experimental conditions indicate that provision of roughage to veal calves is associated with a number of problems. Abnormal behaviour is still occurring. In addition, health problems related to impaired rumen development, milk replacer leaking into the rumen (ruminal milk) and abomasal lesions remain predominant. These partly interrelated problems currently limit improvements in calf welfare and economic benefits that could be reached by a substantial increase of the roughage component of veal calf diets. The aim of this project is to develop novel roughage-based feeding strategies for calves that i) better respond to their behavioural needs, and ii) circumvent and alleviate health problems related to complex interactions between roughage and milk replacer. Correspondingly, the economic and environmental implications of such feeding strategies will be evaluated. In a first step, knowledge will be generated regarding the dietary preferences and behavioural needs of calves under experimental conditions (PhD-project 1). This knowledge will then be applied in comparative studies looking at the impact of different feeding strategies on motivational state, behaviour and health of the calf (PhD-projects 1 and 2). Furthermore, studies will focus on rumen and abomasal health, and digestion and nutrient utilization of the fibrous component of the diet (PhD-project 2). Based on results of these studies, novel feeding strategies for veal calves will be defined, and the economic and environmental consequences of using these strategies will be examined. By integrating animal welfare, economic and environmental aspects in an optimization model, strategies will be identified that not only contribute to the welfare of veal calves, but that are also economically feasible and environmentally sound |
