Effect of inclusion of porcine mucosa hydrolysate in diets varying in lysine content on growth performance and ileal histomorphology of broilers

Porcine mucosa hydrolysate sprayed into a soybean meal carrier (PMH) is a co-product of heparin production from clean endothelial digestive tissues. An experiment was conducted to evaluate growth performance and ileal morphology of broilers fed diets with or without PMH inclusion. There were 8 dietary treatments arranged as a 2 × 4 factorial with two levels of PMH (0 vs. 25 g/kg diet) and four levels of lysine (Lys; 11, 12, 13 and 14 g/kg diet). Diets were formulated to have similar apparent metabolizable energy (AMEn) content and within each Lys level, the indispensable amino acid to AMEn ratio was maintained constant. Birds received the experimental diets from d 1 to 21 and then, a common commercial finisher diet without PMH inclusion from d 21 to 32. Each treatment was replicated five times and the experimental unit was the pen with 32 chicks. An interaction between PMH inclusion and Lys content of the diet was detected for body weight gain (BWG) from d 1 to 7; PMH inclusion improved BWG (P = 0.013) in all cases but the effects were more noticeable in birds fed the low Lys diets (P < 0.05 for the interaction). PMH inclusion did not affect BWG after this age but improved (P < 0.01) feed to gain ratio (F:G) from d 1 to 21. From d 1 to 21, an increase in dietary Lys improved BWG (P < 0.001) but F:G was not affected. From d 22 to 32, when all bird received a common finisher diet, growth performance was not affected by type of diet fed during the starter period. At d 14, villus height and crypt depth of the ileum were not affected by dietary treatment. The results indicate that the inclusion of 25 g PMH/kg diet improved F:G from d 1 to 21 and BWG during the first 7 d of life. From d 1 to 21, broilers required at least 13 g Lys/kg diet to optimize growth performance.