Faba beans in diets for growing-finishing pigs

Summary

Two experiments were carried out to study the effects of using the new faba bean (Vicia faba L.) cultivar Kontu as a domestic protein source for growing-finishing pigs.In Experiment 1,120 pigs were used with a body weight (BW)of 25–110 kg to study the effects of replacing 0, 25, 50, 75,and 100%of rapeseed meal with faba beans in barley +rapeseed meal based diets. Restrictedly fed grower and finisher diets contained 137–317 and 114–260 g kg–1 faba beans, respectively. A barley +soya bean meal based diet was included as a control. The replacement of rapeseed meal with faba beans exerted a quadratic effect on daily weight gain and on the feed conversion ratio of pigs in the growing period and during total fattening (P <0.05).The growth rate of growing pigs declined when 75 or 100%of rapeseed meal was replaced with faba beans.In addition,the complete replacement of rapeseed meal with faba beans decreased feed consumption (P<0.05).The best overall growth performance and feed conversion ratio were observed when 50% of rapeseed meal was replaced with faba beans. These pigs had a better feed conversion ratio than those fed a barley +soya bean based meal diet (P<0.05).The Minolta L*value of the longissimus dorsi muscle decreased linearly (P<0.01) with increasing dietary faba bean levels. This indicates that the meat became darker. Therefore, Experiment 2 was carried out with 20 pigs (25–107 kg BW)to study the effect of faba beans on the colour and ultimate pH of the meat. The pigs were fed barley +soya bean meal or barley + faba bean based diets (243 g kg–1 faba beans).The ultimate pH of the longissimus dorsi muscle was higher in pigs fed the faba bean diet (P=0.05),but meat colour did not differ between the treatments (P>0.05).In conclusion,inclusion of over 200 g kg–1 of faba beans in barley + rapeseed meal based diets is not recommended for growing pigs because it may result in reduced growth performance. Faba beans may influence meat colour,but this phenomenon should be investigated further.