Intestinal development and growth performance of early weaned piglets fed a low-threonine diet
Hamard, A., Sève, B., Le Floc’h, N. (2007) Animal 1 : 8, 1134-1142
22-Nov-2007 (18 years 6 months 14 days ago)Compared to other essential amino acids, Threonine requirements for maintenance
are high and the intestine is thought to contribute extensively to this high requirements.
Therefore, Threonine may be essential for maintaining the structural and functional
integrity of the gut, especially in the weaned piglet, when the small intestine
is immature and grows very quickly. The experiment was carried out in order to
compare the intestinal development and growth performance of early weaned piglets
when fed a Control well-balanced (CT) diet or a low Threonine diet (LT).
Six pairs of littermate weaned piglets, seven days old, were used in the study. On day 7 of live, animals were penned individually, and one pig of each pair was fed the CT and the other the LT diet for 2 weeks. Threonine content in the CT was 9.3 g/kg, and in the LT was 6.5 g/kg. From day 3 onwards, animals belonging to both experimental treatments were fed at the same feeding level, in order to obtain a reduction of 30% in Threonine intake in LT fed animals compared to CT. Blood samples were obtained at different moments and plasma aminoacid concentration determined. At the end of the experimental period, two weeks, animals were slaughtered, and the gastrointestinal tract was removed. In samples obtained from the intestine it was evaluated: the small intestine morphology, the intestinal goblet cell histochemistry, and the enzymatic activity.
Results showed that total consume of Threonine in the LT piglets was 25% lower than that presented by CT fed piglets. Plasmatic levels of Threonine were higher, as expected, in CT fed animals. No modifications on the digestive organ development were found, however, low Threonine supply determined a lowered villi heights and crypt widths (P-diet < 0.05) at the ileum compared to CT piglets. No modifications were found in the maltase and lactase specific activities measured in different sites of the small intestine, but, LT fed piglets presented a lowered aminopeptidase N-specific activity (P-diet < 0.05).
Weaning is a situation in which small intestine structure is often negatively affected; from the results in the present study it is shown that the provision of a well-balanced diet in Threonine is critical in order to maintain the ileal mucosal structure.
Six pairs of littermate weaned piglets, seven days old, were used in the study. On day 7 of live, animals were penned individually, and one pig of each pair was fed the CT and the other the LT diet for 2 weeks. Threonine content in the CT was 9.3 g/kg, and in the LT was 6.5 g/kg. From day 3 onwards, animals belonging to both experimental treatments were fed at the same feeding level, in order to obtain a reduction of 30% in Threonine intake in LT fed animals compared to CT. Blood samples were obtained at different moments and plasma aminoacid concentration determined. At the end of the experimental period, two weeks, animals were slaughtered, and the gastrointestinal tract was removed. In samples obtained from the intestine it was evaluated: the small intestine morphology, the intestinal goblet cell histochemistry, and the enzymatic activity.
Results showed that total consume of Threonine in the LT piglets was 25% lower than that presented by CT fed piglets. Plasmatic levels of Threonine were higher, as expected, in CT fed animals. No modifications on the digestive organ development were found, however, low Threonine supply determined a lowered villi heights and crypt widths (P-diet < 0.05) at the ileum compared to CT piglets. No modifications were found in the maltase and lactase specific activities measured in different sites of the small intestine, but, LT fed piglets presented a lowered aminopeptidase N-specific activity (P-diet < 0.05).
Weaning is a situation in which small intestine structure is often negatively affected; from the results in the present study it is shown that the provision of a well-balanced diet in Threonine is critical in order to maintain the ileal mucosal structure.