Evaluation of extruded soybean and soybean meal on weanling pig diets

Author(s)

Natália Cristina Milani

• Document type: Doctoral Thesis
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
• Defense date: 2021-01-12

Examining board members

Urbano dos Santos Ruiz; Fábio Enrique Lemos Budiño; Marcos Livio Panhoza Tse

• Advisor: Urbano dos Santos Ruiz

Abstract

The study was divided in three experiments, using weanling pigs ranging from 6.02 to 7.26 kg initial BW. Experiment 1 consisted in evaluating ileal and total tract digestibility of nutrients and energy of raw soybean extruded at 82°C; 122°C and 137°C, untoasted soybean meal extruded at 86°C; 120°C and 149°C, deactivated soybean, toasted soybean meal and a nitrogen-free diet in piglets, totaling 9 treatments, 8 repetitions and 1 animal per experimental unit. In experiment 2, 6 diets containing different levels of spray-dried and of toasted or extruded untoasted soybean meal were evaluated in piglets feeding, with 8 repetitions and 4 animals per experimental unit. In experiment 3, 5 diets in which soybean meal was replaced by corn soybean, extruded or deactivated, blends in 50 and 100% were evaluated in piglets feeding, with 8 repetitions and 4 animals per experimental unit. The parameters evaluated in experiments 2 and 3, over a 42 days period, were pigs\' growth performance, diarrhea occurrence, diet nutrient and energy digestibility, blood parameters, gut epithelium integrity and economic viability. A randomized complete block design was adopted in the three experiments, and data were submitted to ANOVA and means were separated using Tukey test (P<0.05). In experiment 1, apparent total tract digestibility of nutrients and apparent and standardized ileal digestibility of CP and amino acids of soybeans, deactivated and extruded at 122°C and 137°, did not differ (P>0.05), but were greater (P<0.05) than in soybean extruded at 82°C. Similar results occurred for toasted or untoasted soybean meal extruded at 120°C and 149°C that presented similar digestibility of nutrients (P>0.05), but higher (P<0.05) than untoasted soybean meal extruded at 86°C. In experiment 2, toasted soybean meal replacement by extruded untoasted soybean meal had no (P<0.05) effects on pigs\' growth performance and intestinal health, however, diets with extruded untoasted soybean meal had higher (P<0.05) cost per kilogram weight. Regarding the spray-dried plasma replacement, pigs fed diets with lower soybean meal levels, regardless of soybean meal source, and higher spray-dried plasma levels, showed greater (P<0.05) average daily gain at two first week experimental period. In experiment 3, the extrusion temperature of the corn-soybean blend was insufficient to inactivate the anti-nutritional factors of soybean and probably this was the reason for the lower (P<0.05) diet protein digestibility and the lower (P<0.05) growth performance of pigs that consumed these diets. The inclusion of extruded corn- soybean blend in replacement of soybean meal reduced (P<0.05) weanling pig growth performance. (AU)

• FAPESP's process: 18/02343-6 - Evaluation of extruded soybeans and extruded soybean meal on weanling pig diets
• Grantee: Natália Cristina Milani
• Support Opportunities: Scholarships in Brazil - Doctorate