Survey on Endoparasites of Dairy Goats in North-Eastern Italy Using a Farm-Tailored Monitoring Approach

Abstract

With the spread of anthelmintic resistance (AR), endoparasite monitoring consolidates its role for a more sustainable targeting of treatments. A survey on endoparasites in dairy goat farms of north-eastern Italy was conducted to test a monitoring approach based on a farm-tailored sample size. Farm management and parasites control practices were investigated in 20 farms through a questionnaire survey. Further, fecal samples were collected (November 2018–September 2019) from 264 animals from 13 farms and were analyzed individually with a modified McMaster method and subsequently pooled to perform a coproculture. Coccidia (78.4%), gastrointestinal strongyles (37.9%), Strongyloides (28.4%), Skrjabinema (18.9%), Trichuris (8.0%) and Nematodirus/Marshallagia (0.4%) were identified. Abundances were higher for coccidia and gastrointestinal strongyles. Haemonchus (71%) was the dominant gastrointestinal nematode. Pasture and age class resulted in the main risk factors at the multivariable analysis through a negative binomial regression model. Results from farm monitoring indicate that our approach can be a cost-effective decision tool to target treatments more effectively, but farmers need to be educated about the importance of parasitological testing, which is currently scarcely implemented, against the risk of AR.

Deaths Due to Mixed Infections with Passalurus ambiguus, Eimeria spp. and Cyniclomyces guttulatus in an Industrial Rabbit Farm in Greece

“…Concerning the sample size used for pooling in both sick and healthy animals (100 faecal samples in each case), research in ruminants indicates that a smaller sample size should also be sufficient in determining the infestation level [99]. A prerequisite for the smaller sample size would be the homogeneous distribution of parasites in each group, that in our case was expected, based on the same symptoms, age and common housing of animals in each group.…”

Quantitative Monitoring of Selected Groups of Parasites in Domestic Ruminants: A Comparative Review

“…Their suggestion on sample size determination, based on both general indications and on practical/logistical constraints, is shown in Figure 1 . The non-proportional increment is clearly demonstrated in the same figure by a more recent study carried out on goat farms [ 28 ], which is proposing a statistical determination of the sample size.…”

“…Specific indications regarding which individuals to sample can be present, as different animal categories can show a different susceptibility to parasites or be specifically targeted for treatment. For instance, symptomatic [ 27 ] and asymptomatic [ 18 ] animals or specific age classes (e.g., calves or young adults in grazing herds/flocks [ 19 , 28 ]) may be preferentially sampled. For coccidiosis, some authors [ 25 , 26 ] recommend only sampling calves/kids.…”

“…Individual and composite samples both have their advantages, such as lower costs and labor for pools and a more complete portray of the infection burden for individual samples. As such, some authors recommend the use of individual samples [ 20 , 28 ], while others prefer pooled samples as more applicable in common practice [ 16 , 32 ]. The literature concerning the use of composite samples is wide and several methodological studies exist.…”

“…Nevertheless, some aspects for GIN were also quite neglected in the literature, for which the quantitative approach is widely adopted. The indications for sample size remained very generic (i.e., 10 animals per farm) and [ 28 ] a formula to optimize the sample size, taking into account the aggregation level, was developed only recently for goats. Moreover, this formula allows the sample size to be tailored to the farm size, providing a relevant step forward in the statistical definition of group-based diagnostics in ruminant farming.…”