1. Department of Animal Nutrition and Feed Management, Wroclaw University of Environmental and Life Sciences, J. Chełmońskiego 38d, 51-630 Wrocław, Poland
2. Statistical Analysis Centre, Wroclaw Medical University, K. Marcinkowskiego 1, 50-368 Wrocław, Poland
3. Institute of Agroecology and Plant Production, Wroclaw University of Environmental and Life Sciences, Pl. Grunwaldzki 24A, 50-363 Wrocław, Poland
4. Department of Applied Mathematics, Faculty of Environmental Engineering and Geodesy, Wrocław University of Environmental and Life Sciences, 50-363 Wroclaw, Poland
5. Department of Filed Crops, Forage and Grasslands, Faculty of Agriculture, University of Zagreb, 10000 Zagreb, Croatia
6. Saatbau Poland Sp. z o.o., Żytnia 1, 55-300 Środa Śląska, Poland