PDF(Pubmed)
Abstract：
BACKGROUND: At present, porcine reproductive and respiratory syndrome (PRRS) caused by the PRRS virus (PRRSV) is one of the most severe epidemics impacting pig farming globally. Despite the fact that a number of studies have been conducted on potential solutions to this problem, none have proven effective. The focus of problem solving is the use of natural ingredients such as plant extracts. Popular throughout Asia, Caesalpinia sappan (CS) is a therapeutic plant that inhibits PRRSV in vitro. Therefore, this study was performed to determine the efficacy of CS extract dietary supplementation on the productive performance, antibody levels, immunological indicators, and lung pathology of PRRSV-challenged weaned pigs. A total of 32 weaned piglets (28 days old) were randomized into 4 groups and kept separately for 14 days. The treatments were organized in a 2 × 2 factorial design involving two factors: PRRSV challenge and supplementation with 1 mg/kg CS extract. The pigs in the PRRSV-challenged groups were intranasally inoculated with 2 mL of PRRSV (VR2332) containing 104 TCID50/mL, while those in the groups not challenged with PRRSV were inoculated with 2 mL of normal saline.
RESULTS: In the PRRSV-challenged group (CS + PRRSV), supplementation with CS extract led to an increase in white blood cells (WBCs) on Day 7 post infection (p < 0.05) and particularly in lymphocytes on Days 7 and 14. The antibody titer was significantly greater in the CS + PRRSV group than in the PRRSV-challenged group not administered CS (PRRSV group) on Day 14 postinfection (S/P = 1.19 vs. 0.78). In addition, CS extract administration decreased the prevalence of pulmonary lesions, which were more prevalent in the PRRSV-challenged pigs that did not receive the CS extract.
CONCLUSIONS: The findings of this study suggest that supplementation with CS extract is beneficial for increasing WBC counts, especially lymphocytes, increasing the levels of antibodies and reducing the prevalence of lung lesions in PRRSV-infected pigs.
RESULTS: In the PRRSV-challenged group (CS + PRRSV), supplementation with CS extract led to an increase in white blood cells (WBCs) on Day 7 post infection (p < 0.05) and particularly in lymphocytes on Days 7 and 14. The antibody titer was significantly greater in the CS + PRRSV group than in the PRRSV-challenged group not administered CS (PRRSV group) on Day 14 postinfection (S/P = 1.19 vs. 0.78). In addition, CS extract administration decreased the prevalence of pulmonary lesions, which were more prevalent in the PRRSV-challenged pigs that did not receive the CS extract.
CONCLUSIONS: The findings of this study suggest that supplementation with CS extract is beneficial for increasing WBC counts, especially lymphocytes, increasing the levels of antibodies and reducing the prevalence of lung lesions in PRRSV-infected pigs.
摘要：
背景：目前，由PRRS病毒（PRRSV）引起的猪繁殖与呼吸综合征（PRRS）是影响全球养猪业的最严重的流行病之一。尽管已经对这个问题的潜在解决方案进行了许多研究，没有一个被证明是有效的。解决问题的重点是使用天然成分，如植物提取物。在整个亚洲都很受欢迎，苏木（CS）是一种体外抑制PRRSV的治疗植物。因此,这项研究是为了确定CS提取物膳食补充剂对生产性能的影响，抗体水平，免疫学指标，和PRRSV攻击的断奶猪的肺病理学。将32只断奶仔猪(28日龄)随机分为4组,分别饲养14天。以2×2阶乘设计组织治疗，涉及两个因素：PRRSV攻击和补充1mg/kgCS提取物。PRRSV攻击组中的猪鼻内接种含有104TCID50/mL的2mLPRRSV（VR2332），而未感染PRRSV的组接种2mL生理盐水。
结果：在PRRSV挑战组（CS+PRRSV）中，CS提取物的补充导致感染后第7天的白细胞(WBC)增加(p<0.05),特别是第7天和第14天的淋巴细胞增加。感染后第14天，CSPRRSV组的抗体滴度明显高于未施用CS的PRRSV攻击组（PRRSV组）（S/P=1.19vs.0.78)。此外,CS提取物给药降低了肺部病变的患病率，在未接受CS提取物的PRRSV攻击的猪中更为普遍。
结论：这项研究的结果表明，补充CS提取物有利于增加白细胞计数，尤其是淋巴细胞,增加PRRSV感染猪的抗体水平和减少肺部病变的患病率。
结果：在PRRSV挑战组（CS+PRRSV）中，CS提取物的补充导致感染后第7天的白细胞(WBC)增加(p<0.05),特别是第7天和第14天的淋巴细胞增加。感染后第14天，CSPRRSV组的抗体滴度明显高于未施用CS的PRRSV攻击组（PRRSV组）（S/P=1.19vs.0.78)。此外,CS提取物给药降低了肺部病变的患病率，在未接受CS提取物的PRRSV攻击的猪中更为普遍。
结论：这项研究的结果表明，补充CS提取物有利于增加白细胞计数，尤其是淋巴细胞,增加PRRSV感染猪的抗体水平和减少肺部病变的患病率。
