The nutritional value of hybrid rye fed to growing pigs

McGhee, Molly Lee

Permalink

https://hdl.handle.net/2142/104912 Copy

Description

Title

The nutritional value of hybrid rye fed to growing pigs

Author(s)

McGhee, Molly Lee

Issue Date

2019-04-24

Director of Research (if dissertation) or Advisor (if thesis)

Stein, Hans H.

Committee Member(s)

• Cardoso, Felipe
• Emmert, Jason L.

Department of Study

Animal Sciences

Discipline

Animal Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• amino acids
• dietary fiber
• energy
• growing pigs
• hybrid rye
• phosphorus digestibility

Abstract

Three experiments were conducted to determine the nutritional composition and digestibility of hybrid rye and other cereal grains fed to growing pigs. In Exp. 1, the objective was to determine the standardized ileal digestibility (SID) of AA in 3 varieties of hybrid rye and in one source of barley, wheat, and corn. Seven ileal cannulated barrows (initial BW = 26.1 ± 2.4 kg) were randomly allotted to a 7 × 7 Latin square design with 7 periods and 7 experimental diets. Six diets included one cereal grain as the sole source of AA, and a N-free diet was used to determine basal endogenous losses of CP and AA. Wheat and barley contained more CP and indispensable AA than hybrid rye, but hybrid rye contained more indispensable AA compared with corn. The SID of CP and most indispensable AA was greater (P < 0.05) in barley, wheat, and corn than in the 3 varieties of rye but concentrations (g/kg) of SID AA in hybrid rye were close to values in corn. In Exp. 2, the objective was to determine the standardized total tract digestibility (STTD) of P in 3 varieties of hybrid rye and in one source of barley, wheat, corn, and sorghum. One hundred twelve growing barrows (initial BW = 13.7 ± 1.3 kg) were allotted to a randomized complete block design with 4 blocks of 28 pigs, 14 experimental diets, and 8 total replicate pigs per treatment. Each diet contained one of the cereal grains as the sole source of P, and there were 2 diets formulated with each cereal grain; the first contained no microbial phytase, and the second contained 1,000 units of microbial phytase per kg of diet. Among the diets that did not include microbial phytase, one hybrid of rye had greater (P < 0.05) STTD of P than wheat, corn, and sorghum. Among the diets containing microbial phytase, there was no difference in STTD of P among hybrid rye, barley, and corn. Microbial phytase improved (P < 0.05) the STTD of P in all cereal grains. In Exp. 3, the objectives were to determine the apparent ileal digestibility (AID) and the apparent total tract digestibility (ATTD) of energy, starch, and total dietary fiber (TDF), as well as the ME in 2 varieties of hybrid rye and in one source of barley, wheat, corn, and sorghum. Twenty-four ileal cannulated barrows (initial BW = 28.1 ± 3.0 kg) were randomly allotted to a 2-period experimental design with 6 experimental diets and 8 total replicate pigs per diet. Each diet consisted of 97% of one cereal grain, thus, the cereal grain was the sole contributor of energy and carbohydrates to the diet. The concentration of TDF was greatest in barley (19.0%), whereas hybrid rye contained 15.2% to 18.1% TDF, and wheat, corn, and sorghum contained less. In all grains, the AID of starch was greater than 90%, and the ATTD of starch was nearly 100%. The AID of TDF was less than 35% for all cereal grains, but the ATTD of TDF was greater (P < 0.05) in the 2 hybrid ryes than in the other ingredients. The AID of GE was greater (P < 0.05) in wheat, corn, and sorghum than in barley and hybrid rye. The ATTD of GE was also greater (P < 0.05) in corn than in hybrid rye, barley, and sorghum, but there were no differences between corn and wheat, nor among one hybrid of rye, wheat, and sorghum. On a DM basis, the ME in the 2 sources of hybrid rye was 3,459 and 3,499 kcal/kg, respectively, which was less (P < 0.05) than in corn and wheat. In conclusion, the SID of AA in hybrid rye is less than in other cereal grains; however, because of the greater concentration of AA in hybrid rye than in corn, the quantities of standardized ileal digestible AA are not different between corn and hybrid rye. Without microbial phytase, the STTD of P in hybrid rye is greater than in other cereal grains, which is likely due to the greater intrinsic phytase activity in rye, and the addition of microbial phytase improves the STTD of P in all cereal grains. Hybrid rye results in reduced pre-cecal absorption of energy compared with wheat, corn, and sorghum, but because hindgut fermentation of fiber is greater in rye than in other cereal grains, the ME in hybrid rye is not different from the ME in barley and sorghum, but less than in corn and wheat.

Graduation Semester

2019-05

Type of Resource

text

Permalink

http://hdl.handle.net/2142/104912

Copyright and License Information

Copyright 2019 Molly McGhee

Owning Collections