Effect of nonwaxy and waxy sorghum on growth, carcass traits, and glucose and insulin kinetics of growing-finishing barrows and gilts12

Abstract

Two experiments were conducted to determine the effect of nonwaxy (amylose and amylopectin starch) or waxy (amylopectin starch) sorghum on growth, carcass traits, and glucose and insulin kinetics of pigs. In Exp. 1 (95-d), 60 crossbred barrows or gilts (initial and final BW of 24 and 104 kg) were allotted to three treatments with five replications of four pigs per replicate pen in a randomized complete block design. The dietary treatments for Exp. 1 were 1) corn-soybean meal (C-SBM) diet, 2) sorghum-SBM (red pericarp, non-waxy), and 3) sorghum-SBM (red pericarp, waxy). In Exp. 2, 28 crossbred barrows (initial and final BW of 24 and 64 kg) were allotted to two treatments with three replications of four or five pigs per replicate pen in a randomized complete block design. Growth data were collected for 49 d, and then 20 barrows were fitted with jugular catheters, and then a glucose tolerance test (500 mg glucose/kg BW), an insulin challenge test (0.1 IU of porcine insulin/kg BW), and a feeding challenge were conducted. The dietary treatments for Exp. 2 were 1) sorghum-SBM (white pericarp, nonwaxy) and 2) sorghum-SBM (white pericarp, waxy). In Exp. 1, ADG (P = 0.10) and ADFI (as-fed basis; P = 0.02) were increased (P = 0.10) and gain:feed was decreased (P = 0.04) in pigs fed the sorghum-SBM diets relative to those fed the C-SBM diet. These responses may have resulted from the lower energy content of sorghum relative to corn. Plasma NEFA concentration (collected after a 16-h fast on d 77) was decreased (P = 0.08) in pigs fed the waxy sorghum-SBM diet relative to those fed the nonwaxy sorghum-SBM diet. Kilograms of carcass fat was decreased (P = 0.07) in pigs fed the waxy sorghum-SBM diet relative to those fed the nonwaxy sorghum-SBM diet. In Exp. 2, there was no effect (P = 0.57 to 0.93) of sorghum starch type on growth performance by pigs. During the glucose tolerance and insulin challenge tests, there were no effects (P = 0.16 to 0.98) of diet on glucose or insulin kinetics. During the feeding challenge, glucose (P = 0.02) and plasma urea N (P = 0.06) area under the response curves from 0 to 90 min were decreased in pigs fed the waxy sorghum-SBM diet. Feeding waxy sorghum had minimal effects on growth and carcass traits relative to pigs fed corn or nonwaxy sorghum. Waxy sorghum vs. nonwaxy sorghum had no effect on glucose or insulin kinetics in pigs.

Effect of Italian heavy pig diets based on different barley varieties with or without non-starch polysaccharides degrading enzymes on growth performance, carcass characteristics and fresh thigh quality

“…The present findings suggest that Perez et al's (1980) equation applied in the current study to calculate the DE of the 2 barley varieties could be more appropriate than the Fairbairn et al's (1999) Equation 1 used in the previous study (Prandini, Sigolo, Giuberti, et al 2015). The literature reports contrasting results about the effect of starch type on carcass characteristics (Camp et al 2003;Shelton et al 2004;Doti et al 2014;Prandini, Sigolo, Giuberti, et al 2015). These discrepancies could be addressed to the different experimental conditions used such as growth phase of pigs, level of inclusion of high glycemic index starch sources, and type of starchy ingredients.…”

TRIENNIAL GROWTH SYMPOSIUM: Effects of polymeric carbohydrates on growth and development in pigs1

“…A possible explanation could be that glucose specifically inhibits protein degradation, as indicated by the study of Fulks et al (1975). However, a study with waxy sorghum showed that the only carcass trait where there was a tendency to be affected by feeding of waxy sorghum was kilograms of carcass fat, which was slightly decreased in pigs fed waxy sorghum relative to pigs fed corn or nonwaxy sorghum (Table 5; Shelton et al, 2004). A study with waxy corn (Camp et al, 2003) reported a decrease in lOth-rib fat thickness, which, however, was not affected by the diet in the study of Shelton et al (2004).…”

“…Thus, presently there is not enough evidence that the type of starch influences carcass composition of pigs. From the study with sorghum starch type, it was also evident that the starch type had no effect on either glucose or insulin kinetics (Table 6 and Figure 3; Shelton et al, 2004). During the feeding challenge, plasma concentrations and the area under the curve for glucose were numerically decreased in pigs fed the waxy sorghum compared with those fed the nonwaxy sorghum diet.…”

“…However, a study with waxy sorghum showed that the only carcass trait where there was a tendency to be affected by feeding of waxy sorghum was kilograms of carcass fat, which was slightly decreased in pigs fed waxy sorghum relative to pigs fed corn or nonwaxy sorghum (Table 5; Shelton et al, 2004). A study with waxy corn (Camp et al, 2003) reported a decrease in lOth-rib fat thickness, which, however, was not affected by the diet in the study of Shelton et al (2004). In a study of Camp et al (2003), an increase in carcass weight and length, but no effect on fatness or leanness, was reported when feeding waxy corn.…”

“…This increase in dietary carbohydrates may improve growth performance and affect plasma metabolites brought about by rapidly digestible and absorbable carbohydrates. However, the results have been variable; dietary sucrose addition and the use of waxy cereals have shown variable results (Camp et al, 2003;Shelton et al, 2004). Waxy cereals (i.e., sorghum and corn) contain approximately 100% amylopectin, which in vitro and in vivo has been shown to be more rapidly available than amylose (Rooney and Pflugfelder, 1986).…”