Control of gastrointestinal helminths in small ruminants to prevent anthelmintic resistance: the Italian experience

Abstract

Helminth infections are ubiquitous in grazing ruminants and cause significant costs due to production losses. Moreover, anthelmintic resistance (AR) in parasites is now widespread throughout Europe and poses a major threat to the sustainability of modern ruminant livestock farming. Epidemiological data on the prevalence and distribution of gastrointestinal nematodes, cestodes and liver-and rumen-flukes in Italian small ruminants are outdated and fragmentary. However, anthelmintics are commonly used to control these infections and often without prior diagnosis. Compared to other European countries, few reports of AR in small ruminants against levamisole, ivermectin and benzimidazoles have been published in Italy, but recent studies suggest that this phenomenon is spreading. Increased and integrated research efforts in developing innovative approaches to control helminth infections and AR are needed and must be tailored to the peculiarities of each context in order to be effectively implemented.This manuscript provides an overview on helminth prevalence and distribution, sustainable treatment strategies and integrated control approaches in small ruminants in Italy. The implementation of targeted treatments and targeted selective treatments is discussed based on different parameters, such as faecal egg count, degree of anaemia (FAMACHA © method), milk production and body condition score. In addition, several Italian studies have also investigated the implementation of alternative strategies such as the use of different natural bioactive compounds or genetic selection for resistance and resilience to helminth infections. These concrete solutions for helminth management in small ruminant farms in the country are reported and discussed, representing a valid example for other Mediterranean countries.

Epidemiological Data Regarding the Distribution of Gastrointestinal Parasites in Albanian Small Ruminants

“…Top of Form Use of the multiple control strategies can reduce the risk of evolution of pathogen. Strategies to prevent anthelmintic resistance are described previously by other colleagues in Italy (Maurizio et al, 2023;Zanzani et al, 2014). Also the use of herbal anthelmintics can be an alternative that is cheap, safe and can overcome the problem of resistance with the presence of multitarget compounds (Liu et al, 2020;Mares et al, 2023;Barua et a l., 2023).…”

Parasitological transitions: selected outcomes from the XXXII Congress of the Italian Society for Parasitology

“…The usefulness of comparing and discussing control practices has already been demonstrated at the European level through different collaborative projects (Charlier et al ., 2022 ), however this exercise is still lacking at the national level. The Italian perspective on the control of gastrointestinal helminth infections was deeply analysed during the symposium and subsequently reported in this SI (Maurizio et al ., 2023 ). The work includes a nationwide epidemiological update on parasite prevalence and on the possible emergence of anthelmintic resistance.…”

Effect of pomegranate (Punica granatum) anthelmintic treatment on milk production in dairy sheep naturally infected with gastrointestinal nematodes

“…The findings showed that, in sheep and goats, the average farm-level prevalence of AR was 48 and 51% for benzimidazoles, 29 and 44% for macrocyclic lactones other than moxidectin, and 32 and 20% for levamisole ( 16 , 17 ). There have not been many published cases of AR in small ruminants in Italy against levamisole, macrocyclic lactones, and benzimidazoles ( 18 ). Nevertheless, in 2007, there were reports of AR in small ruminants in central and southern Italy for benzimidazoles, levamisole, and ivermectin ( 19 , 20 ).…”