Table 2.
A summary of the effects of weaning Stress on intestinal immune function in piglets.
| Weaning age | Sampling time points | Significant results | References |
|---|---|---|---|
| 21-d-old piglets | Piglets are divided into Sucking group (S), Weaned group (W), and FMT + Weaned group (FW), and 4 piglets were killed at 24 days of age | mRNA expression of IL-6 and TNF-α is increased, while IL-10 is decreased in the jejunum and colon after weaning | Ma et al. (13) |
| 28-d-old piglets | Piglets are killed at 0, 1, 2, 5, and 8 d postweaning | the levels of IL-1β, IL-6,and TNF-α are increased during the first 2 days postweaning | Pie et al. (14) |
| 21-d-old piglets | Piglets are divided into two treatments: suckling piglet group (SP) and weaning piglet group (WP), and piglets were killed at 25 days of age | the WP group has significantly higher colonic IL-1β and lower IL-10 content than the SP group | Tang et al. (28) |
| 21-d-old piglets | Piglets are killed at 0, 3, 7, and 14 d postweaning | mRNA levels of TNF-a and IL-6 are increased at 3 d and 7 d post-weaning | Hu et al. (30) |
| 21-d-old piglets | Weaned and sucking piglets are killed at 25 days of age | pro-inflammatory signals (tumor necrosis factor and NO synthases 2 are increased in weaned piglets | Zhu et al. (44) |
| 19-d-old piglets; 28-d-old piglets | Piglets are killed at twenty-four hours postweaning | the early-weaned pigs (weaned at 19 days of age) have higher numbers of intestinal mast cells than late-weaned pigs (weaned at 28 days of age) | Moeser et al. (70) |
| Piglets weaned at 15, 18, 21, 23, or 28 days of age | Piglets of the five groups with different weaning days are slaughtered at 35 days of age | Lamina propria immune cell density particularly mucosal mast cells is increased in early weaning (15 to 21-day weaning age) piglets | Smith et al. (71) |
| 21-d-old piglets | Piglets are killed at 0, 0.5, 1, 2, 4, and 7 d after weaning | inflammatory T-cell numbers and local expression of matrix metalloproteinase stromelysin are increased | McCracken et al. (113) |
| 26-d-old piglets | Piglets are killed at 0, 1, 2, and 4d after weaning | the CD4+/CD8+ T-lymphocytes ratio is decreased after weaning | Spreeuwenberg et al. (114) |
| 16-d-old piglets; 28-d-old piglets | The pigs were killed at 7 weeks and 20 weeks | the early-weaned pigs sustained hyperplasia of intestinal mast cells at 7 weeks and 20 weeks | Pohl et al. (116) |
| 21-d-old piglets | Piglets are killed at 0, 1, 3, 7, and 14d after weaning | TNF-α mRNA expression is enhanced from day 7 to 14; the abundance of TLR4 and IFN-γ mRNA expression are increased during the first 24 h after weaning | Deng et al. (117) |
| 21-d-old piglets | Piglets are killed at days 0, 15, 30, and 45 postweaning | IFN-γ, IL-1α, IL-8, IL-10, IL-12α, and TGF-β in the jejunum, ileum, and colon are increased during 15 d postweaning | de Groot et al. (118) |
| 21-d-old piglets | Piglets are sacrificed at 0, 1, 7, or 14 d after weaning | the mRNA levels of IFN-γ, iNOS, IL-6, IL-8, IL-12, and IL-22 are increased in the jejunum at 7 and 14 d after weaning | Yi et al. (119) |
| 14-d-old piglets | Piglets are slaughtered until they were on d 0, 3, 7, 14, and 21 after weaning | early weaning disrupted IFN-γ/IL-4, IL-2/sIL-2R, and T lymphocyte balance | Cao et al. (120) |
| 28-d-old piglets | Piglets are slaughtered at 0, 7, 14, and 21 d after weaning | the mRNA and protein expression of TNF-α and IFN-γ are increased at post-weaning day 7 | Zhong et al. (121) |
TNF-α, tumor necrosis factor-α; IFN-γ, interferon-γ; IL-1β, interleukin-1β; IL-2, interleukin-2; IL-4, interleukin-4; IL-6, interleukin-6; IL-8, interleukin-8; IL-10, interleukin-10; IL-12α, interleukin-12α; TLR4, toll-like receptor 4; TGF-β, transforming growth factor-β1.