In vivo efficacy of chicory silage against parasitic nematodes in cattle

Infections with parasitic nematodes are a persistent risk for grazing cattle, which is met with widespread use of synthetic anthelmintics. However, heavy reliance on these drugs may lead to selection of drug-resistant nematodes. Integrated control strategies, including anti-parasitic crops, are needed. Chicory (Cichorium intybus) can have an impact against sheep nematodes, but this has not been investigated in cattle. Our study aimed to assess the effect of chicory on infections with abomasal (Ostertagia ostertagi) and intestinal (Cooperia oncophora ) nematodes in stabled calves. Chicory (cv. Spadona) was ensiled and fermented for 5-12 weeks. 15 Jersey male calves (2-4 months) were stratified by live weight and randomly allocated to 2 groups: chicory (CHI, n=9) and control (CON, n=6). CHI and CON calves were fed with chicory silage and hay ad libitum, resp., for 8 weeks. Daily intake was monitored and protein/energy intake in both groups was equalized during the study. After 2 weeks on the diet all calves were infected with approx. 10,000 O.ostertagi and 65,000 C. oncophora third-stage larvae. Fecal excretion of nematode eggs was calculated as number of eggs per g of dried faeces (FECDM). Individual live weight was measured once a week. 6 weeks after infection calves were slaughtered for worm recovery. FECDM and live weights were analysed by ANOVA using repeated measurements. Log-transformed worm counts were analysed by ANOVA. Mean FECDM were not different between groups (P=0.14) but live weight gains during the study were significantly higher in CHI calves (+ 35%; P<0.05). Mean worm counts for O. ostertagi adults were 1599 and 3752 in CHI and CON, respectively (P<0.01). Worm counting of C. oncophora is undergoing. Based on these preliminary results we conclude that chicory may have an anti-parasitic effect against O. ostertagi