International audience | Clinical indicators such as diarrhoea (DISCO) or anaemia (FAMACHA©) are used as a measure for targeted selective treatments against gastrointestinal nematodes (GIN). Enteric cestodes such as Moniezia may interfere directly with DISCO or indirectly with the FAMACHA© score. We investigated 821 Ouled Djellal rams naturally infected in a steppe environment (GIN alone, cestodes alone, GIN and cestodes) or not. The rams were treated with ivermectin 2 months before being slaughtered to reduce the impact of nematodes on the clinical scores; however, persistent or newly acquired GINs were not related to both scores. Of the non-infected rams (n = 296), 26% identified as needing treatment against GIN using the FAMACHA score, and 34.5% using DISCO would have been thus selected. This implies that the clinical indicators used for the targeted selective treatment of gastrointestinal nematodes are not fully reliable when a low infection is recorded and may well be influenced by confounding factors. As expected, only DISCO was affected by cestode infection, and we suggest that the presence of Moniezia should also be taken into consideration. | Des indicateurs cliniques tels que la diarrhée (DISCO) ou l'anémie (FAMACHA © ) sont utilisés comme mesure pour des traitements sélectifs ciblés contre les nématodes gastro-intestinaux (GIN). Les cestodes entériques tels que Moniezia peuvent interférer directement avec DISCO ou indirectement avec le score FAMACHA © . Nous avons enquêté sur 821 béliers Ouled Djellal naturellement infectés en milieu steppique (GIN seul, cestodes seuls, GIN et cestodes) ou non. Les béliers ont été traités à l'ivermectine 2 mois avant d'être abattus pour réduire l'impact des nématodes sur les scores cliniques ; cependant, les GIN persistants ou nouvellement acquis n'étaient pas liés aux deux scores. Parmi les béliers non infectés ( n = 296), 26% identifiés comme ayant besoin d'un traitement contre le GIN selon le score FAMACHA, et 34,5% selon DISCO auraient ainsi été sélectionnés. Cela implique que les indicateurs cliniques utilisés pour le traitement sélectif ciblé des nématodes gastro-intestinaux ne sont pas entièrement fiables lorsqu'une faible infection est enregistrée et peuvent bien être influencés par des facteurs de confusion. Comme prévu, seul DISCO a été affecté par l'infection par cestode, et nous suggérons que la présence de Moniezia soit également prise en considération.

International audience | Clinical indicators such as diarrhoea (DISCO) or anaemia (FAMACHA©) are used as a measure for targeted selective treatments against gastrointestinal nematodes (GIN). Enteric cestodes such as Moniezia may interfere directly with DISCO or indirectly with the FAMACHA© score. We investigated 821 Ouled Djellal rams naturally infected in a steppe environment (GIN alone, cestodes alone, GIN and cestodes) or not. The rams were treated with ivermectin 2 months before being slaughtered to reduce the impact of nematodes on the clinical scores; however, persistent or newly acquired GINs were not related to both scores. Of the non-infected rams (n = 296), 26% identified as needing treatment against GIN using the FAMACHA score, and 34.5% using DISCO would have been thus selected. This implies that the clinical indicators used for the targeted selective treatment of gastrointestinal nematodes are not fully reliable when a low infection is recorded and may well be influenced by confounding factors. As expected, only DISCO was affected by cestode infection, and we suggest that the presence of Moniezia should also be taken into consideration.