Animal proteins such as milk products, blood products, fish meal, chicken meal (CM), and poultry by-product meal (PBM) are usually used as amino acid sources in diets for weanling pigs because the nutrients in these ingredients are highly digestible and because they do not contain the anti-nutritional factors that are present in conventional soybean meal. Due to the cost of animal protein sources, other alternatives have been investigated. One alternative is soybean meal which has been fermented to destroy antinutritional factors and increase protein digestibility. Fermented soybean meal (FSBM) has been shown to be able to replace milk, blood proteins, and fish meal in diets fed to weanling pigs. However, there are no data on whether or not fermented soybean meal can replace chicken meal and poultry by-product meal. An experiment was, therefore, performed to test the hypothesis that fermented soybean meal can replace chicken meal and poultry by-product meal in diets fed to weanling pigs without negatively affecting growth performance.

Experimental design

A total of 175 newly weaned pigs were allotted to five dietary treatments in three phases (seven, seven, and 14 days, respectively). Five phase 1 diets  that all contained 15% whey powder and 3% protein plasma, were formulated. The negative control diet contained no other animal products. The positive control diet contained fish meal, and three experimental diets contained chicken meal, poultry by-product meal, or  fermented soybean meal. The Phase 2 and Phase 3 diets were formulated in the same way except that protein plasma was excluded, and the inclusion rate of whey powder was decreased to 10% in Phase 2 and 5% in Phase 3.

Table 1. Inclusion rates of selected ingredients in Phase 1, Phase 2, and Phase 3 diets

In phase 1, no differences were observed in body weight, average daily gain, average daily feed intake, or gain:feed ratio among pigs fed any of the different diets (Table 2). In phase 2, no differences were observed in average daily feed intake among treatments. However, final body weight, average daily gain, and gain:feed were less in pigs fed the negative control diet than in pigs fed the other diets, but no differences  among pigs fed the other diets were observed. In phase 3, no differences in any of the performance measures were observed among pigs fed any of the diets. Overall, the gain:feed ratio in pigs fed the positive control diet was greater than in pigs fed the other diets, which did not differ. No differences in the other performance measures were observed.

Table 2. Growth performance of nursery pigs fed diets containing fish meal, chicken meal, poultry meal, and fermented soybean meal

^a-bMeans within a row lacking a common superscript letter are different (P< 0.05).

• Fermented soybean meal may be used  as an alternative to animal protein sources in diets fed to weanling pigs.
• Fermented soybean meal may replace chicken meal or poultry by-product meal in diets fed to pigs during the initial 28 days post-weaning without affecting growth performance.

This research report is based on unpublished research by O. J. Rojas and H. H. Stein.