A harmonized sampling approach in combination with spatial modelling is required to update current knowledge of fasciolosis in dairy cattle in Europe. Within the scope of the EU project GLOWORM, samples from 3,359 randomly selected farms in 849 municipalities in Belgium, Germany, Ireland, Poland and Sweden were collected and their infection status assessed using an indirect bulk tank milk (BTM) enzyme-linked immunosorbent assay (ELISA). Dairy farms were considered exposed when the optical density ratio (ODR) exceeded the 0.3 cut-off. Two ensemble-modelling techniques, Random Forests (RF) and Boosted Regression Trees (BRT), were used to obtain the spatial distribution of the probability of exposure to Fasciola hepatica using remotely sensed environmental variables (1-km spatial resolution) and interpolated values from meteorological stations as predictors. The median ODRs amounted to 0.31, 0.12, 0.54, 0.25 and 0.44 for Belgium, Germany, Ireland, Poland and southern Sweden, respectively. Using the 0.3 threshold, 571 municipalities were categorized as positive and 429 as negative. RF was seen as capable of predicting the spatial distribution of exposure with an area under the receiver operation characteristic (ROC) curve (AUC) of 0.83 (0.96 for BRT). Both models identified rainfall and temperature as the most important factors for probability of exposure. Areas of high and low exposure were identified by both models, with BRT better at discriminating between low-probability and high-probability exposure; this model may therefore be more useful in practise. Given a harmonized sampling strategy, it should be possible to generate robust spatial models for fasciolosis in dairy cattle in Europe to be used as input for temporal models and for the detection of deviations in baseline probability. Further research is required for model output in areas outside the eco-climatic range investigated.

This long-term observational cohort study was carried out to evaluate the effect of caprine arthritis-encephalitis virus (CAEV) infection on the quantitative and qualitative characteristics of milk production in dairy goats. For this purpose, a dairy herd comprising both CAEV-infected and uninfected female goats was observed for 12 consecutive years. Records on daily milk yield, somatic cell count (SCC), and contents of the major milk components (fat, protein and lactose) were collected every month. In total, 3,042 records (1,114 from CAEV-positive and 1,928 from CAEV-negative animals) from 177 female goats were used for statistical analysis. The multi-trait repeatability test-day animal model using the derivative-free multivariate analysis package with the average information-REML method was applied to eliminate the influence of factors other than CAEV infection on milk production in goats. The statistical significance of the differences between estimates for seropositive and seronegative goats was evaluated using Student's t-test. The effect of age of goats (parity) on their serological status was also estimated with the one-trait repeatability test-day model. The serological status of goats was linked to parity: the higher the parity, the greater the probability of CAEV infection. No significant differences between infected and uninfected goats with respect to daily milk yield and SCC were found. On the other hand, the milk of uninfected goats contained more total protein (3.40% vs. 3.35%), fat (3.69% vs. 3.54%), and lactose (4.30% vs. 4.25%) than the milk of infected goats. Even though these differences were highly significant, they were small when expressed numerically.

Currently, there are three classes of anthelmintics most commonly used in small ruminants: the benzimidazoles (BZs), macrocyclic lactones (MLs) and cholinergic agonists (especially levamisole; LEV). The widespread use of those products has led to the emergence of drug-resistant parasite strains which represents a serious threat to the livestock industry. In the present study, we describe for the first time a case of resistance to anthelmintics in goats in Romania. The study was carried out in 2021 in a dairy goat herd from the Transylvania region. Two types of diagnostic methods were used to confirm anthelmintic resistance (AR). First, the faecal egg count reduction test (FECRT), an in vivo AR diagnostic method, was used to evaluate the efficacy of eprinomectin (EPM). The results of this test were analysed applying two different calculative methods that are used only in treated animals (without the control group). Furthermore, two in vitro methods were used: the egg hatch test (EHT) for the detection of resistance to BZs, and the larval development test (LDT) for detection of resistance to all three classes of anthelmintics. The results of FECRT indicate the resistance of gastrointestinal nematodes (GINs) to EPM in both calculative methods (FECR₁ = −88% and FECR₂ = −202%). In addition, the results obtained for ivermectin aglycone (IVM-AG) in LDT also indicate resistance to drugs from MLs group, especially avermectins. Similarly, the results of in vitro methods (EHT and LDT) indicate resistance to BZs in this herd. LEV was the only drug that stopped the development of L3 larvae 100% (LDT). H. contortus was the only nematode species found in coproculture after EPM treatment. Furthermore, H. contotus L3 larvae was the only species found in the wells with the highest concentrations of thiabendazole (TBZ) and IVM-AG in LDT. This suggests that resistance to both BZs and MLs was present for that species.

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