Weaning Stress in Piglets Alters the Expression of Intestinal Proteins Involved in Fat Absorption

Abstract

Background In vivo data on intestinal fat absorption in weanling piglets are scarce. Objective This study aimed to investigate the effect of weaning stress on intestinal fat absorption. Methods 18 seven-day-old sow-reared piglets (Duroc-Landrace-Yorkshire) were assigned to 3 groups (n = 6/group, 3 males and 3 females per group). Piglets were nursed by sows until 24 d of age (suckling piglets, S), or weaned at 21 d of age to a corn-soybean meal-based diet until 24 d (3 d post-weaning, W 3) or 28 d (7 d post-weaning, W 7) of age, respectively. Duodenum, jejunum, and ileum were collected to determine intestinal morphology and abundance of proteins related to fat absorption. Result Compared with the S group, the W 3 group had lower villus height (17%-34%) and villus height to crypt depth ratio (13%-53%), as well as a 1-1.45 times greater crypt depth, which in the W7 group was 1.18-1.31, 0.69-1.15, and 1.47-1.87 times greater than in the W 3 group, respectively. Compared with the S group, weaning stress for both 3 and 7 d reduced intestinal alkaline phosphatase activity (26%-73%), serum lipids (26%-54%), and abundances of proteins related to fatty acid transport (FATP4 and I-FABP) and chylomicron assembly (APOA4, MTTP, APOB, and APOA1) in the duodenum and ileum (10%-55%), as well as in the jejunum (25%-85%). All these indexes did not differ between W 3 and W 7 groups. Compared with the S group, the W 3 group had lower mRNA levels of duodenal APOA4 and APOA1 (25%-50%), as well as jejunal FATP4, IFABP, MTTP, APOA4, and APOA1 (35%-50%), whereas they were 5-15% and 10-37% lower in the W 7 group than in the W 3 group, respectively, Conclusion Weaning stress in piglets attenuates the expression of intestinal proteins related to fatty acid transport (FATP4 and I-FABP) and chylomicron synthesis (APOA4).

Expressions of Insulin-like Growth Factor System among Different Breeds Impact Piglets’ Growth during Weaning

“…Hence, the changes in serum IGFs concentrations may affect the growth rate of weaned piglets. Previously, it has been found that piglets exhibited stress damage on the 3rd day after weaning [17]. However, the changes in the IGF system of piglets during this weaning period (3rd day after weaning) are still unclear.…”