Effect of Exogenous Enzymes and a Novel GLP2 on Gut Health and Growth Performance

Matthew Duane Asmus, Purdue University

Abstract

We have a need to increase protein production as the world population continues to increase. Seeing that land and resources are a limited commodity, the need to raise pigs as efficiently as possible will continue to increase. Similarly, as the industry switches further away from antibiotics and growth performance technologies, the need for wholistic alternatives continues to increase. Therefore, the focus of this dissertation primarily focuses on technologies to improve pig growth performance both in the nursery (Chapter 3 and 4) as well as the finisher (Chapter 2 and 3). In chapter two, two experiments were conducted to evaluate the effect of β-mannanase and lysine level as well as β-glucanase and β-mannanase in combination during ractopamine feeding prior to market. In Exp. 1, 343 crossbred pigs were blocked by ancestry, sex, and initial BW (97.3 ± 1.36 kg) and allocated to mixed gender pens (5 or 6 pigs/pen) to 5 treatments with 10 or 12 pens/treatment. Dietary treatments included: 1) low lysine (0.80% SID Lys; LL); 2) LL+mannanase (0.08 MU/kg); 3) high lysine (0.95% SID Lys; HL); 4) HL+mannanase (0.08 MU/kg); 5) As treatment 3 + 4% choice white grease (CWG). Diets were corn-soy based (LL and HL=3335 and CWG=3517 kcal ME/kg) and contained 7.5 ppm ractopamine. One pig/pen was harvested on d 7 and 21, with remaining pigs harvested on d 35. For d 7-21 and 0-35 pigs fed the HL diets tended (P<0.06) to have improved G:F compared to pigs fed LL diets. For d 21-28 (P<0.03) and 0-35 (P<0.03) pigs fed LL diets had greater ADFI than pigs fed HL diets. Pigs fed mannanase tended to have increased ADFI (P<0.06) d 21-28 and improved (P<0.10) ADG (984 vs 937 g/d) from d 21-35. Pigs fed the CWG diet had improved ADG (P<0.04) from d 21-35 and 0-35 and for periods d 7-21 (P<0.01) and 0-35 (P<0.07) had reduced ADFI compared to pigs fed the HL diet. This resulted in improved G:F (P<0.01) from d 14-21, 21-28, 7-21, 21-35, and 0-35. Pigs harvested on d 7 fed mannanase diets had increased (P<0.01) carcass yield and tended to have increased (P< 0.06) loin depth, but reduced yield (P<0.06) on d 21. Pigs fed LL diets had increased (P<0.05) backfat (BF) depth compared to pigs fed HL diets on d 7. Pigs fed HL diets harvested on d 21 had reduced (P<0.01) BF depth and increased (P<0.03) percent lean versus pigs fed LL diets. Pigs fed CWG had increased (P<0.02) BF depth d 21 and d 35 and reduced (P<0.03) percent lean d 21 compared to pigs fed the HL diet. Overall, pigs fed HL diets had reduced (P<0.04) BF depth and tended to have increased (P<0.08) percent lean when compared to pigs fed LL and CWG diets.

Degree

Ph.D.

Advisors

Richert, Purdue University.

Subject Area

Immunology|Alternative Medicine|Animal sciences|Bioinformatics|Cellular biology|Developmental biology|Genetics|Medicine|Microbiology|Pharmaceutical sciences

COinS