Three studies were conducted to compare the effects of 4 different porcine intestinal mucosa products (PEP2, PEP2+, Peptone 50, and PEP-NS; TechMix Inc., Stewart, MN) with select menhaden fish meal (SMFM) on nursery pig performance. These intestine-derived mucosal ingredients are byproducts of heparin production, with a similar amount of mucosal protein, but differ based on the carriers with which they are co-dried. Enzymatically processed vegetable protein is the carrier for PEP2 whereas PEP2+ is co-dried with enzymatically processed vegetable proteins and biomass from crystalline AA production. Peptone 50 uses vegetable protein as its carrier while PEP-NS is co-dried with byproducts of corn wet milling and biomass from crystalline AA production. In Exp. 1, 300 weanling pigs (PIC 327 × 1050; initially 5.4 kg and 19 d of age) were allotted to 1 of 5 dietary treatments with 12 replications and 5 pigs per pen. Diets consisted of a negative control (NC) containing no specialty protein sources, NC with 4, 8, or 12% PEP2 in phases 1 (d 0 to 11) and 2 (d 11 to 25), and a positive control containing 4% spray-dried animal plasma (SDAP) in phase 1 and 4% SMFM in phase 2. From d 0 to 11, pigs fed SDAP had greater (P < 0.05) ADG and G:F than pigs fed PEP2. From d 11 to 25, increasing PEP2 increased (quadratic; P < 0.01) ADG and G:F, with the greatest response observed at 4%. In Exp. 2, 960 weanling pigs (Newsham GPK35 × PIC 380; initially 5.6 kg, and 20 d of age) were allotted to 1 of 5 dietary treatments with 32 pigs per pen and 6 replications per treatment. Diets included a control with 4.5% SDAP in phase 1 (d 0 to 7) and no specialty protein sources in phase 2 (d 7 to 21) or the control diet with 6% of the following: SMFM, PEP2+, Peptone 50, or PEP-NS. From d 0 to 21, pigs fed diets containing SMFM, PEP2+, or PEP-NS had greater (P < 0.05) ADG than pigs fed the control or 6% Peptone 50. In Exp. 3, 180 nursery pigs (PIC 327 × 1050; initially 6.4 kg and 28 d of age) were allotted to 1 of 5 dietary treatments with 5 pigs per pen and 6 replications per treatment. Treatment diets were fed from d 7 to 21 postweaning. Treatments consisted of a NC, NC with 3, 6, 9, or 12% PEP-NS, or NC with 6% SMFM. Overall, pigs fed increasing PEP-NS had improved (quadratic; P < 0.01) ADG and G:F, with the greatest improvement observed in pigs fed 6% PEP-NS, similar to those fed 6% SMFM. These results suggest PEP2, PEP2+, and PEP-NS can effectively replace SMFM in nursery pig diets.