title: The site of intestinal disappearance of DL-methionine and methionine hydroxy analog differs in pigs.
abstract: A study was conducted with pigs to determine the sites of and the influence of dietary wheat middlings (WM) as a fiber source on the absorption of dl-Met (DLM) and dl-2-hydroxy-4-methylthio butanoic acid (HMTBA). Twelve 25-kg barrows were used in a replicated 6 × 4 incomplete Latin-square design with 6 diets and 4 periods per pig. Each pig was surgically fitted with simple T-cannulas in the terminal duodenum and ileum 2 wk before the initiation of the experiment and housed in a stainless-steel metabolism crate. The 6 diets were arranged in a 2 × 3 factorial of WM at 0 (CON) or 8% and Met source including none, DLM, or HMTBA. Supplemental DLM doubled the duodenal free Met concentration from 9.6 to 19.6 g/100 g of DMI. Supplemental DLM also increased the apparent ileal digestibility (AID) of free Met from 52 to 92% (P < 0.05). Adding 8% WM increased (P < 0.01) duodenal NDF concentrations by 2 g/100 g of DMI and decreased (P < 0.05) AID of free Met. No HMTBA was detected in digesta collected from the duodenum or ileum of pigs fed the CON + HMTBA or the WM + HMTBA diets, indicating complete absorption before the terminal duodenum regardless of WM inclusion. Interactions between Met supplementation and WM were observed for the digestibility of all other nutrients (P < 0.05). Fiber and AA digestibility in the ileum were the greatest for the CON + HMTBA diet, and least for the WM + HMTBA diet. The CON + HMTBA diet had greater AID of ADF, NDF, CP, and Thr, and greater AID of ADF, NDF, ash, Arg, Ile, Gly, and Pro when compared with the CON and CON + DLM diets, respectively (P < 0.05). The WM + HMTBA had less AID of ADF, CP, and all AA with the exception of Lys, Trp, and Val when compared with the CON + HMTBA (P < 0.05). In summary, absorption of HMTBA in the pig is complete by the end of the duodenum, but negative interaction between HMTBA and WM can decrease the AID of most AA.
authors.affiliation: Department of Animal Sciences, Purdue University, West Lafayette, IN 47907-2054, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Jendza
authors.forename: P A
authors.initials: PA
authors.lastname: Geraert
authors.forename: D
authors.initials: D
authors.lastname: Ragland
authors.forename: O
authors.initials: O
authors.lastname: Adeola
mesh_terms: D000824:Animal Nutritional Physiological Phenomena / Q000502:physiology; D000818:Animals; D004043:Dietary Fiber / Q000378:metabolism; D004063:Digestion / Q000502:physiology; D005243:Feces / Q000737:chemistry; D007408:Intestinal Absorption / Q000502:physiology; D007421:Intestine, Small / Q000378:metabolism*; D008297:Male; D008715:Methionine / Q000031:analogs & derivatives* / Q000378:metabolism*; D013552:Swine / Q000378:metabolism*
chemical_list: D004043:Dietary Fiber; C008391:alpha-hydroxy-gamma-methylmercaptobutyric acid; D008715:Methionine