摘要
试验旨在探明饲粮添加不同水平叶酸(FA)对圆环病毒-2(PCV-2)攻击下断奶仔猪增重和组织病变的影响。选用45头PCV-2阴性、初重8.44kg的健康去势、28d断奶DLY仔猪,饲喂添加不同水平FA(0、0.3、15mg/kg)的饲粮7 d后,进行PCV-2攻毒,继续饲喂相应饲粮28 d。第1、7(攻毒前)、21天和第35天采集组织样品;测定体重、腹泻指数、组织病变、血清PCV-2特异抗体、猪瘟抗体和细胞因子水平。结果表明:无PCV-2攻击,断奶应激导致仔猪免疫组织损伤,饲粮添加15 mg/kg FA可明显改善淋巴组织病变;PCV-2攻击导致免疫抑制与组织损伤,仔猪体重极显著降低(P<0.01);饲粮不添加FA仔猪免疫抑制和组织病变最严重,添加0.3 mg/kg FA缓解了免疫抑制而组织病变减轻,添加15 mg/kg FA则不利于组织修复。
To detect the effects of dietary supplementation with folic acid （FA） on body weight and histopathological changes of weanling piglets with PCV-2 challenging, a 2x3 factorial （two states： PCV-2 challenge or not; three added FA levels： O, 0.3, or 15 mg/kg） randomized block design was conducted in this study. Fourty-five PCV-2 negative, 8.44 ± 0. 12 kg, crossbred （Duroc × Landrace × Yorkshire） castrated piglets were weaned at （28 ± 1） days of age, and fed ad libitum with three diets for 35 days, respectively. Seven piglets from each diet group were challenged with PCV-2 in the morning of d7. Blood and tissue samples were collected on dl, d7 （without PCV-2 challenge）, d21 ＆ d35. The bodyweight, diarrhea incidence, histopathological change, and serum levels of cytokines were measured, respectively. Results showed that immune tissue damages were induced by intense stress during weaning in piglets without PCV-2 infection; Dietary supplementation with FA 15 mg/kg obviously restored the tissue damage. After 14 days since PCV-2 challenge, the piglets had the depressed body weight （P〈0.01） with the intensified immunosuppression and tissue damage; Compared with the basal diet, the Diet supplementation with FA 0.3 mg/kg relieved partly the immunosuppression and tissue damages; but the diet supplementation with 15 mg/kg FA disadvantaged restoration of immune system in piglets. It implied that the suitable level of dietary FA might be different for piglets with different PCV-2infection status.
出处
《中国畜牧杂志》
CAS
北大核心
2012年第3期29-34,共6页
Chinese Journal of Animal Science
基金
教育部长江学者和创新团队发展计划(IRTO555-5)
关键词
叶酸
圆环病毒-2
组织病变
免疫抑制
断奶仔猪
folic acid
porcine circovirus-2
weanling piglet
histopathological changes
immunosuppression
