Nutritive value for pigs of a formic acid preserved blood-mucosa product

A digestibility and balance experiment was conducted to evaluate the nutritive value of formic acid preserved blood-mucosa product (FBM) for pigs. The FBM consisted of a mixture of slaughterhouse blood, gastrointestinal mucosa, and proteins and fat separated from slaughterhouse process waters. The mixture was coagulated at 90°C, filtered, sterilized at 120°C for 20 min, and preserved with formic acid (12–14 1 per 1000 kg). The FBM contained 171 g dry matter (DM) kg−1, 680 g crude protein (CP) kg−1 DM and 19.5 g crude fat (CF) kg−1 DM. The experiment was conducted with eight barrows at live weights from 77 to 101 kg. The experimental diets were barley-based and supplemented with FBM or soya bean meal (SBM; 489 g CP kg−1 DM) at two levels: 30 or 70 g CP kg−1 DM. parent total tract digestibilities of nutrients in FBM and SBM were: organic matter 81.8 and 86.0%, CP 87.2 and 90.6%, CF 78.9 and 71.6%, and energy 80.8 and 84.6%, respectively. The digestible and net energy contents were 21.2 and 14.0 MJ kg−1 DM for FBM, and 17.5 and 11.4 MJ kg−1 DM for SBM, respectively. The pigs given FBM diets retained more nitrogen than those given SBM diets (P < 0.05), which was most probably due to a higher lysine content in FBM compared to SBM (8.2 vs. 5.7 g per 100 g CP). The results indicate that FBM is a feasible protein and energy source for pigs. The high lysine content in the product makes it a valuable feedstuff to be incorporated into cereal-based diets.