Effects of increasing the farm produced content in organic feeds on pig performances

Summary

In three experimental facilities (Exp.1, 2 and 3), two organic diets, one complex including processed feedstuffs as wheat bran and heat-treated soya beans (control), the other simplified and containing over 80 % of cereal and pulses (CP), were compared for growing-finishing pigs. The base components of the CP diets were moist maize grain, wheat and faba beans in Exp.1, triticale plus coloured-flowered peas in Exp.2, and triticale, oats, white-flowered peas and faba beans in Exp.3. The diets were formulated with similar energetic values and a lysine content (0.70 g ileal digestible lysine /MJ NE) 20 % lower than the conventional mean requirement for growing pigs. However, the CP diet had a lysine proportion 30% lower than requirement in Exp.1 and did not achieve the ideal protein pattern in Exp. 2 and 3. Diets were given in all experiments from 35 to 115 kg according to a feeding plan. Respectively 96, 100 and 80 pigs were used in Exp.1, 2 and 3 and were blocked in straw bedded pens of 4, 25 and 40.
In Exp.1, pigs receiving the control diet had a lower average feed intake than those offered the CP diet (p<0.01), whereas feed intake was similar between treatments for Exp.1 and Exp2. Daily weight gains (g/d) for pigs offered the control and the CP diets were respectively of 673 and 669 in Exp.1 (p>0.05), 760 and 719 in Exp.2 (p=0.04) and 684 and 677 in Exp.3 (p>0.05). The feed conversion rate (g/g) was high and reached respectively 3.28 and 3.41 in Exp.1 (p=0.01), 3.2 and 3.,4 in Exp.2, 3.3 and 3.4 in Exp.3. The lean meat rate did not differ significantly in Exp.1, 2 and 3, for pigs given control and CP diets. The study underlines that with a moderate growth objective, an organic feed with a low energetic and protein concentration can yield a satisfying lean meat rate. In spite of a tendency for lower performances, especially concerning the feed conversion rate, a simplified diet based on cereal and pulses can be used, taking into account its economical interest for organic pig production.