Effect of Starch Sources Extrusion on Performance of Young pigs

Abstract

At weaning, the young pig is subjected to myriad of stressors (e.g. change in nutrition, separation from mother and littermates, new environment) which cause a reduction of growth. Reduced feed intake, limited digestive enzyme development and challenges to the digestive tract may all have serious consequences for the development and survival of the young pig. These factors often lead to the post-weaning `growth check' commonly observed during this period of time, which can have a major impact on subsequent performance. Starch is the main source of energy in piglet diets, but native starch is not completely digested in the small intestine of young pigs. Undigested starch enters the large intestine where it can be fermented, resulting in increasing the incidence of diarrhea and reducing piglet performance. More digestible source of the starch and heat processing of the cereal can improve digestibility in piglet, and reduce growth check. An experiment was conducted to evaluate the effects of starch sources and extrusion on growth performance, nutrient digestibility of weaning pigs. This study was a 2 x 3 factorial arrangement of treatments conducted in a randomized complete block (RCB) design. The first factor was ingredient processing method and the second factor was three different carbohydrate sources (corn, barley or rice). A total of 144 weaning pigs ([Yorkshire × Landrace] × Duroc) averaging 7.02 ± 1.07 kg body weight, weaned at 28 ± 3 days of age were allotted to 6 treatments in 6 replicates with 4 pigs per pen. All nutrients of experimental diets were met or exceeded NRC requirements (1998). During the whole experimental period, pigs fed raw carbohydrate sources had improved ADG (625 vs 545 g

P<0.01 and 469 vs 416 g

P<0.01), and G/F ratio was also increased when pigs were fed no extruded cereals (0.711 vs 0.652 g

P<0.01 and 0.695 vs 0.645 g

P<0.01). Among raw cereals, raw rice treatment tended to increase growth performance compared to raw corn treatment at 2-5 week (corn 593 vs rice 661

P<0.1), Protein digestibility of barley and rice was increased when extruded sources were provided but nitrogen retention was numerically decreased as pigs were fed extruded sources. Growth performance of weaning pigs was improved when raw carbohydrate sources were provided. This results demonstrated that extrusion of carbohydrate sources in weaning pigs diet did not show any positive response on nutrient digestibility. Consequently, raw carbohydrate sources rather than processed sources can be utilized in weaning pigs diet without detrimental effects on nutrient digestibility or growth performance.