Dietary starch sources affect net portal appearance of amino acids and glucose in growing pigs

Abstract

Four male pigs (Duroc 3 Landrace 3 Yorkshire; average initial (mean 6 SEM) BW 5 22.5 6 1.1 kg), fitted with permanent catheters in the portal vein, ileal vein and carotid artery, were used in a 4 3 4 Latin square experimental design to measure the effect of dietary starch sources on the net portal appearance of glucose and amino acids. Dietary starch sources were resistant starch (RS), maize, sticky rice and brown rice. Diets were provided at 0730, 1530 and 2330 h during a 6-day adjustment period and 1-day collection period. On day 7 of each period, blood samples were collected from the portal vein and carotid artery at 0730 h (prior to feeding) and hourly up to 8 h after meal. Blood samples were used to determine glucose, amino acid, packed cell volume and partial pressure of oxygen (pO 2 ). When calculated per 100 g feed intake, cumulative portal glucose appearance was lower (P , 0.05) for resistant starch than for maize, sticky rice or brown rice up to 8 h after the meal. Cumulative portal glucose appearance was higher (P , 0.05) for sticky rice and brown rice than for other diets until 4 h after the meal, but maize had higher cumulative glucose appearance after 4 h. Net cumulative portal concentrations of most amino acids for resistant starch were also reduced (P , 0.05) than for the other starch sources. Cumulative portal appearance of amino acid represented 48.39%, 63.76%, 61.80% and 59.18% of dietary intake for resistant starch, maize, sticky rice and brown rice, respectively. Collectively, our results indicate that dietary starch sources substantially affect the appearance of amino acids and glucose in the portal circulation.

Grain Sorghum: A Conundrum for Chicken-Meat Production

“…Accumulating evidence suggests that the provision of some slowly digestible starch in broiler diets is beneficial for feed conversion efficiency [79][80][81]. One possibility is that retarded starch digestion rates provide a greater supply of glucose to the lower small intestine which spares amino acids from catabolism for energy to meet the gut mucosa's requirements thereby permitting the entry of amino acids into the systemic circulation to become available for protein deposition [22].…”

Plasma glucose response and glycemic indices in pigs fed diets differing in in vitro hydrolysis indices

“…), housed individually in stainless steel metabolism crates in a temperature-controlled room (from 238C to 268C), were fitted with an indwelling jugular vein catheter (Deng et al, 2010), which was carried out as described by Li et al (2008). Only five pigs were used because of difficulties related to animal management.…”

“…The kinetics of starch digestion are an emerging issue in swine nutrition (Menoyo et al, 2011), because of their implications for productive performance (Mateos et al, 2007), nutrient digestibility (Vicente et al, 2008), metabolism of amino acids (Li et al, 2008), feed intake (van Kempen et al, 2007), carcass composition (Bach Knudsen, 2011) and physiological responses (Regmi et al, 2011).…”

“…-E-mail: francesco.masoero@unicatt.it Although the effect of different starch sources with various physicochemical characteristics (such as starch structure, amylose content, resistant starch content (RS) and degree of gelatinization) on postprandial blood glucose appearance and physiological responses has been reported both for humans (Englyst et al, 1996) and pigs (Li et al, 2008;van Kempen et al, 2010), their contribution in the kinetics of the in vivo postprandial glucose response is not clearly understood. In particular, in vivo responses are not always consistent (Regmi et al, 2011), and results may vary considerably because of the confounding effect of nutrients other than starch or when the range of digestibility is not sufficiently wide (Noah et al, 2000;Regmi et al, 2010).…”

“…In particular, our results showed that diets with high HI increased the incremental plasma glucose appearance in jugular-catheterized pigs when compared with low HI diets in the same level of TS (P , 0.05). Different postprandial glucose responses were detected when pigs (Li et al, 2008;van Kempen et al, 2010) and humans (Behall et al, 2002) consumed various sources of dietary starch with a wide range in starch digestion kinetics. The reason for the different incremental plasma glucose levels may be related primarily to the hydrolysis of starch in the digestive tract, starch hydrolysis being a rate-limiting factor for the appearance of glucose (Cummings and Englyst, 1995).…”