Body weight gain and nutrient utilization in starter pigs that are liquid-fed high-moisture corn-based diets supplemented with phytase

Abstract

. M. 2010. Body weight gain and nutrient utilization in starter pigs that are liquid-fed high-moisture corn-based diets supplemented with phytase. Can. J. Anim. Sci. 90: 45Á55. A total of 384 starter pigs were used to examine the application of exogenous phytase in high-moisture corn (HMC)-based liquid diets. Pigs were randomly assigned to 24 pens in six blocks. Pens were randomly assigned one of four HMC-based diets formulated to vary in total phosphorus (P) content (Low, Medium and High), with phytase added to only the Low P diet (Phy). Body weight gain and feed intake were monitored until body weight exceeded 20 kg. Apparent total tract digestibility of crude protein and P were measured on day 21 (Phase II) and day 42 (Phase III). At the end of the trial, two pigs from each pen were sacrificed for analysis of carcass composition and evaluation of metacarpals. Pigs fed the Phy treatment had increased digestibility of crude protein (P B0.05) and P (P00.062) in Phase III, and increased metacarpal breaking strength (PB0.01) and P content (PB0.05). Average daily gain, feed intake, and carcass composition were not affected by treatment (P0.05). In conclusion, performance of starter pigs fed liquid HMC-based diets was maintained at dietary P levels below established requirements, but addition of phytase improved bone strength and mineralization. This study provides evidence for the effectiveness of phytase, and that P requirement for maximum rate of weight gain in pigs is not sufficient for maximum skeletal development.Key words: High-moisture corn, liquid feed, phosphorus, phytase, starter pigs Columbus, D., Zhu, C. L., Pluske, J. R. et de Lange, C. F. M. 2010. Gain de poids et assimilation des e´le´ments nutritifs par les porcs de de´marrage nourris avec une ration liquide de maı¨s a`haute teneur en eau enrichie de phytase. Can. J. Anim. Sci. 90: 45Á55. Les auteurs ont recouru a`384 porcs de de´marrage pour e´tudier l'utilite´de la phytase exoge`ne dans une ration liquide a`base de maı¨s a`haute teneur en eau (MHTE). Les animaux ont e´te´re´partis au hasard entre 24 enclos, en six blocs. Quatre rations de MHTE ont ensuite e´te´attribue´es au hasard aux enclos. Ces rations avaient e´te´pre´pare´es pour faire varier la concentration de phosphore (P) (faible, moyenne et e´leve´e) et la phytase n'a e´te´ajoute´e qu'a`la ration contenant le moins de P (Phy). Les auteurs ont surveille´le poids corporel et l'ingestion d'aliments jusqu'a`ce que le poids des animaux de´passe 20 kg. Ils ont mesure´la digestibilite´apparente totale des prote´ines brutes et du P dans le tube digestif le 21 e jour (Phase II) et le 42 e jour (Phase III). À la fin de l'expe´rience, deux sujets de chaque enclos ont e´te´sacrifie´s et on a analyse´la composition de leur carcasse ainsi qu'e´value´leurs me´tacarpiens. Les porcs recevant la ration Phy assimilaient mieux les prote´ines brutes (PB0,05) et le P (P00,062) a`la Phase III, et leurs me´tacarpiens e´taient plus solides (PB0,01), tout en contenant plus de P (PB0,05). Le traitement n'affecte p...