Premium
Digestibility, ruminal fermentation, blood metabolites and antioxidant status in ewes supplemented with DL ‐methionine or hydroxy‐4 (methylthio) butanoic acid isopropyl ester
Author(s) -
BaghbanzadehNobari B.,
Taghizadeh A.,
Khorvash M.,
ParnianKhajehdizaj F.,
Maloney S. K.,
HashemzadehCigari F.,
Ghaffari A. H.
Publication year - 2017
Publication title -
journal of animal physiology and animal nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.651
H-Index - 56
eISSN - 1439-0396
pISSN - 0931-2439
DOI - 10.1111/jpn.12600
Subject(s) - rumen , dry matter , chemistry , latin square , neutral detergent fiber , fermentation , zoology , food science , propionate , hay , valerate , biochemistry , biology , butyrate
Summary The effects of supplementing ewe diets with either DL ‐methionine ( DL ‐Met) or 2‐hydroxy‐4 (methylthio) butanoic acid isopropyl ester ( HMB i) were investigated on ruminal in situ degradability of grain and forage diets, in vivo digestibility, rumen fermentation, blood metabolites and antioxidant status. Six ruminally cannulated ewes were used in a replicated 3 × 3 Latin square design with 28‐day periods. The dietary treatments were as follows: (i) no supplemental Met (control; CON ), (ii) DL ‐Met at 1.2 g/kg DM intake and (iii) HMB i at 1.8 g/kg dry matter ( DM ) intake. Corn grain, barley grain and alfalfa hay were evaluated for their ruminal degradability by both in situ incubation and effective degradability measurements of DM , neutral detergent fibre ( NDF ) and acid detergent fibre ( ADF ). Compared to other treatments, HMB i supplementation increased (p < 0.05) the digestibility of organic matter, crude protein and NDF and also tended (p = 0.08) to increase the digestibility of DM and ADF . Moreover, HMB i supplementation increased (p < 0.01) total VFA concentrations, the molar proportions of valerate and iso‐butyrate in the rumen. Compared to the CON treatment, DL ‐Met and HMB i treatments tended (p = 0.08) to increase the molar proportion of acetate but decreased (p < 0.05) ruminal ammonia‐N concentration. Ewes supplemented with HMB i and DL ‐Met recorded greater (p < 0.05) serum concentrations of glutathione peroxidase, total antioxidant capacity and superoxide dismutase than the CON treatment. Serum concentrations of glucose, total protein, albumin, high‐density lipoprotein and very low‐density lipoprotein were greater (p < 0.01) and serum urea nitrogen (p < 0.05), malonyl dialdehyde and triglyceride were lower (p < 0.02) in the HMB i and DL ‐Met animals than in the CON ewes. The results concluded that HMB i is a very effective form of dietary Met supplementation for ewes with a positive effect on digestion, rumen fermentation and serum antioxidant function.