Efficacy of flukicides against Fasciola hepatica and first report of triclabendazole resistance on German sheep farms

Fasciola hepatica infections lead to severe health problems and production losses in sheep farming, if not treated effectively. Triclabendazole has been used extensively over decades due to its unique efficacy range against all definitive hostfluke stages but published data about the susceptibility of F. hepatica to anthelmintics in Germany are lacking. This study aimed to identify current F. hepatica infections in German sheep flocks by coproscopic examinations and to evaluate the efficacy of anthelmintics with a focus on triclabendazole in a field study conducted from 2020 to 2022. Initial screening included 71 sheep farms, many of them with known history of fasciolosis. In this highly biased sample set, the frequency of F. hepatica infection at individual sheep and farm level were 12.8% and 35.2%, respectively. Additionally, eggs of Paramphistominae were found at frequencies of 4.8% and 15.5% at individual sheep and farm level, respectively. Due to low egg shedding intensity, faecal egg count reduction (FECR) tests could only be conducted on a few farms. The efficacy of triclabendazole was tested on 11 farms and albendazole on one farm, including 3–53 sheep/farm. Individual faecal samples were collected before and two weeks after treatment to evaluate the FECR using the sedimentation or FLUKEFINDER® or a modified FLUKEFINDER® method. On all farms a coproantigen reduction test was conducted in parallel. Lacking efficacy of triclabendazole even at double dosage was shown on one farm associated with a high number of animal losses due to acute fasciolosis. On this farm, the Fasciola miracidium development test was additionally performed, revealing a high in vitro ovicidal activity of albendazole while closantel was effective in vivo. On all other farms, sufficient efficacy of triclabendazole was observed. In conclusion, triclabendazole resistance appears not to be widespread on German sheep farms but, when present, can have serious effects on animal health

Identification of Tsetse (Glossina spp.) using matrix-assisted laser desorption/ionisation time of flight mass spectrometry

Glossina (G.) spp. (Diptera: Glossinidae), known as tsetse flies, are vectors of African trypanosomes that cause sleeping sickness in humans and nagana in domestic livestock. Knowledge on tsetse distribution and accurate species identification help identify potential vector intervention sites. Morphological species identification of tsetse is challenging and sometimes not accurate. The matrix-assisted laser desorption/ionisation time of flight mass spectrometry (MALDI TOF MS) technique, already standardised for microbial identification, could become a standard method for tsetse fly diagnostics. Therefore, a unique spectra reference database was created for five lab-reared species of riverine-, savannah- and forest- type tsetse flies and incorporated with the commercial Biotyper 3.0 database. The standard formic acid/acetonitrile extraction of male and female whole insects and their body parts (head, thorax, abdomen, wings and legs) was used to obtain the flies' proteins. The computed composite correlation index and cluster analysis revealed the suitability of any tsetse body part for a rapid taxonomical identification. Phyloproteomic analysis revealed that the peak patterns of G. brevipalpis differed greatly from the other tsetse. This outcome was comparable to previous theories that they might be considered as a sister group to other tsetse spp. Freshly extracted samples were found to be matched at the species level. However, sex differentiation proved to be less reliable. Similarly processed samples of the common house fly Musca domestica (Diptera: Muscidae; strain: Lei) did not yield any match with the tsetse reference database. The inclusion of additional strains of morphologically defined wild caught flies of known origin and the availability of large-scale mass spectrometry data could facilitate rapid tsetse species identification in the futur

The predictive value of prostate cancer biomarkers depends on age and time to diagnosis: towards a biologically-based screening strategy.

Both benign and malignant prostate diseases elevate total prostate-specific antigen (tPSA), and the incidence of benign disease increases markedly with age. There is evidence, however, that free-to-total PSA ratio (%fPSA) and human kallikrein 2 (hK2) more closely reflect the malignant process. We tested the hypothesis that tPSA levels are more strongly predictive of cancer in younger when compared to older men, whereas %fPSA and hK2 are more strongly predictive in men tested closer to diagnosis. The study included 13,676 men age >/= 44 in Sweden, where PSA screening was uncommon during the study period. fPSA, tPSA and hK2 were measured in archived plasma collected during 1974-1986 in 501 men subsequently diagnosed with prostate cancer up to 1999 and in 1,292 matched controls. The predictive value of tPSA was lower in older men (p = 0.003) but was not strongly affected by time to diagnosis (p = 0.3); the predictive value of hK2 was higher closer to diagnosis (p < 0.0005) but was not modified by age (p = 0.7). A model including tPSA, fPSA and hK2 was superior (p = 0.02) to tPSA alone in older (AUC 0.819 vs. 0.794), but not in younger men (0.758 vs. 0.759). Total PSA can be used as a single marker at early middle age to predict long-term risk of prostate cancer and thus to determine intensity of subsequent screening. In contrast, %fPSA and hK2 add important predictive value in older men and much closer to diagnosis. Strategies for prostate cancer screening should be based on thorough understanding of the interaction of kallikrein-related biomarkers with prostate pathobiology

Identification of Tsetse (<i>Glossina</i> spp.) Using Matrix-Assisted Laser Desorption/Ionisation Time of Flight Mass Spectrometry

<div><p><i>Glossina (G.)</i> spp. (Diptera: Glossinidae), known as tsetse flies, are vectors of African trypanosomes that cause sleeping sickness in humans and nagana in domestic livestock. Knowledge on tsetse distribution and accurate species identification help identify potential vector intervention sites. Morphological species identification of tsetse is challenging and sometimes not accurate. The matrix-assisted laser desorption/ionisation time of flight mass spectrometry (MALDI TOF MS) technique, already standardised for microbial identification, could become a standard method for tsetse fly diagnostics. Therefore, a unique spectra reference database was created for five lab-reared species of riverine-, savannah- and forest- type tsetse flies and incorporated with the commercial Biotyper 3.0 database. The standard formic acid/acetonitrile extraction of male and female whole insects and their body parts (head, thorax, abdomen, wings and legs) was used to obtain the flies' proteins. The computed composite correlation index and cluster analysis revealed the suitability of any tsetse body part for a rapid taxonomical identification. Phyloproteomic analysis revealed that the peak patterns of <i>G. brevipalpis</i> differed greatly from the other tsetse. This outcome was comparable to previous theories that they might be considered as a sister group to other tsetse spp. Freshly extracted samples were found to be matched at the species level. However, sex differentiation proved to be less reliable. Similarly processed samples of the common house fly <i>Musca dome</i>stica (Diptera: Muscidae; strain: Lei) did not yield any match with the tsetse reference database. The inclusion of additional strains of morphologically defined wild caught flies of known origin and the availability of large-scale mass spectrometry data could facilitate rapid tsetse species identification in the future.</p></div

Laboratory-reared <i>Glossina (G.)</i> spp. selected for the compilation of spectra database.

1<p>Tsetse & Trypanosomiasis Research Institute, Tanga, Tanzania;</p>2<p>International Atomic Energy Agency, Seibersdorf, Austria.</p

Coproscopical diagnosis of patent Fasciola hepatica infections in sheep - A comparison between standard sedimentation, FLUKEFINDER® and a combination of both.

The liver fluke Fasciola hepatica is a highly pathogenic and zoonotic trematode with a cosmopolitan distribution. In livestock, infections may lead to significant economic losses if not diagnosed promptly and treated effectively. Particularly for small ruminants, the standard method for the detection of fluke infection is based on coproscopical methods such as the sedimentation method, which detects F. hepatica eggs in faecal samples. In this respect a recent innovative coproscopical approach to diagnose patent infections is the FLUKEFINDER® method, which relies on differential sieving before sedimentation. These two methods and a combination of both methods that allows larger amounts of faeces to be processed with the FLUKEFINDER® apparatus were compared, to assess which method is most appropriate to determine the prevalence and intensity of F. hepatica egg shedding. The methods were compared for their ability to recover eggs from ovine faecal samples containing different numbers of fluke eggs per gram (EPG) of faeces and diluting the samples further by mixing with faeces from uninfected sheep. To compare the specificity of the test procedures, positive and negative samples with a low EPG were analysed in parallel by an investigator blinded to the nature of the samples. Significant differences concerning the EPG outcome were found: The FLUKEFINDER® method demonstrated the highest EPG values (p < 0.001) in the undiluted samples as well as in all mixing levels, followed by the modified FLUKEFINDER® method. The standard sedimentation showed the lowest EPG values and the highest variability between technical replicates. The precision of the FLUKEFINDER® method and the modified FLUKEFINDER® method were significantly higher than the precision of the standard sedimentation as determined by comparison of variability between technical replicates. The highest raw egg counts were detected using the modified FLUKEFINDER® method. The FLUKEFINDER® method and the combined method showed a sensitivity of 100 % even at the lowest egg concentrations, whereas the sensitivity of the standard sedimentation was 98.1 % for the same set of samples (i.e. one false negative sample). In a separate investigation aiming to estimate the specificity no differences were found between the three methods: all protocols showed 100 % specificity and were able to correctly distinguish between truly positive and truly negative samples without any evidence of cross-contamination between positive and negative samples processed in parallel

Score-oriented main spectra dendrogram of whole <i>Glossina spp</i>. extracts.

<p>The dendrogram was calculated by Biotyper 3.0 software with distance measure set at correlation and linkage set at complete.</p

Spectra reproducibility among the biological and technical replicates.

<p>Overlay view of 27 spectra obtained from biological and technical replicates of <i>Glossina austeni</i> female whole insect. The masses (in Da) of the ions are shown on the <i>x</i>-axis and the <i>m/z</i> value stands for mass to charge ratio. On the y-axis, the relative intensity of the ions (a.u., arbitrary units) is shown. In the insert, zoomed m/z 5000 to 5200 displays the uniformity among the measured spectra and the stacked view m/z 9000 to 12500 provides a direct comparison of all 27 measured spectra.</p