胃肠道线虫(GIN)感染影响小反刍动物的健康,福利,和农业系统的生产。有机农业中驱虫抗药性的上升和合成药物使用的调节正在推动GIN控制的可持续替代方案的研究和开发。一种替代方法是喂养含有次生代谢物(PSM)的植物,例如,原花青素(PA,syn.缩合单宁)显示出驱虫潜力。然而,PSM可能会损害性能,由于适口性降低,因此摄入量降低,消化率甚至毒性作用。在这项研究中,我们测试了羔羊食用石南花的抗寄生虫和抗营养作用之间的权衡。还探讨了额外喂食线虫真菌(Duddingtoniaflagrans)对幼虫发育的影响。羔羊感染了环孢菌或未感染的对照,随意提供希瑟,或在感染专利期间控制切碎的干草22天。进入专利期八天,在5天的时间内,用D.flag补充(或保持未补充)被寄生的羔羊。记录性能和感染指标,测量了石南花草和对照干草中的多酚水平,以研究它们与活性的关系。羔羊以大约20%的干物质摄入量消耗希瑟,这足以通过减少总卵产量表现出显着的驱虫作用(P=0.007),与干草喂养的羔羊相比;与对照羔羊相比,希瑟喂养的羔羊随时间减少的幅度几乎是10倍。显示了对生产的负面影响,因为以希瑟为食的羔羊比以干草为食的羔羊体重低6%(P<0.001),即使石南花的干物质摄入量(drymatteradvance,degainment,degainment,degaining,drainmatteradvances,eventhoughwenttime.D.flag补充使感染羔羊粪便中的幼虫恢复降低了31.8%(P=0.003),尽管没有观察到摄食石南和D.flagrans之间的相互作用(P=0.337)。PA、或饮食和鸡蛋产量中的其他多酚亚组,这表明,希瑟摄食和驱虫作用之间的任何关联都不是简单而直接地归因于测得的多酚。在这项研究中,石南花的摄入水平对D.flagrans没有拮抗作用,演示这些方法可以组合使用,但对整体驱虫效果没有累加作用。总之,希瑟喂养可以帮助减少受感染绵羊的卵子产量,但是在20%的MI对羔羊性能的负面影响是可以预期的,这可能超过任何抗寄生虫的好处。
Gastrointestinal nematode (GIN) infections impact small ruminant health, welfare, and production across farming systems. Rising anthelmintic resistance and regulation of synthetic drug use in organic farming is driving research and development of sustainable alternatives for GIN control. One alternative is the feeding of plants that contain secondary metabolites (PSMs) e.g., proanthocyanidins (PA, syn. condensed tannins) that have shown anthelmintic potential. However, PSMs can potentially impair performance, arising from reduced palatability and thus intake, digestibility or even toxicity effects. In this study, we tested the trade-off between the antiparasitic and anti-nutritional effects of heather consumption by lambs. The impact of additional feeding of a nematophagous fungus (Duddingtonia flagrans) on larval development was also explored. Lambs infected with Teladorsagia circumcincta or uninfected controls, were offered ad libitum heather, or a control chopped hay for 22 days during the infection patent period. Eight days into the patent period, parasitised lambs were supplemented (or remained unsupplemented) with D. flagrans for a 5-day period. Performance and infection metrics were recorded, and polyphenol levels in the heather and control hay were measured to investigate their association with activity. The lambs consumed heather at approximately 20% of their dry matter intake, which was sufficient to exhibit significant anthelmintic effects via a reduction in total egg output (P = 0.007), compared to hay-fed lambs; the magnitude of the reduction over time in heather fed lambs was almost 10-fold compared to control lambs. Negative effects on production were shown, as heather-fed lambs weighed 6% less than hay-fed lambs (P < 0.001), even though dry matter intake (DMI) of heather increased over time. D. flagrans supplementation lowered larval recovery in the faeces of infected lambs by 31.8% (P = 0.003), although no interactions between feeding heather and D. flagrans were observed (P = 0.337). There was no significant correlation between PA, or other polyphenol subgroups in the diet and egg output, which suggests that any association between heather feeding and anthelmintic effect is not simply and directly attributable to the measured polyphenols. The level of heather intake in this study showed no antagonistic effects on D. flagrans, demonstrating the methods can be used in combination, but provide no additive effect on overall anthelmintic efficacies. In conclusion, heather feeding can assist to reduce egg outputs in infected sheep, but at 20% of DMI negative effects on lamb performance can be expected which may outweigh any antiparasitic benefits.