Giardiosis and other enteropathogenic infections: a study on diarrhoeic calves in Southern Germany.

Diarrhoea induces massive problems in the rearing of calves. The aim of the study was to obtain current data about the frequency of Giardia spp., Cryptosporidium spp. and Eimeria spp. in diarrhoeic calves in Southern Germany with the particular focus on giardiosis

Strongyle infections and parasitic control strategies in German horses - a risk assessment

Background: As a consequence of the increasing levels of anthelmintic resistance in cyathostomes, new strategies for equine parasite control are being implemented. To assess the potential risks of these, the occurrence of strongyles was evaluated in a group of 1887 horses. The distribution of fecal egg counts (FECs), the frequency of anthelmintic drug use, and the deworming intervals were also analyzed. Between June 2012 and May 2013, 1887 fecal samples from either selectively or strategically dewormed horses were collected at 195 horse farms all over Germany and analyzed quantitatively with a modified McMaster technique. All samples with FEC >= 20 eggs per gram (EPG) were subjected to coproculture to generate third-stage larvae (LIII) for species differentiation. Results: Egg counts were below the limit of detection (20 EPG) in 1046 (55.4%) samples and above it in 841 (44.6%) samples. Strongylus vulgaris larvae were identified in two of the 841 positive samples. Infections with cyathostomes were found on every farm. The most frequently applied anthelmintic was ivermectin (788/50.8%), followed by pyrantel (336/21.6%). The mean time since last treatment was 6.3 months. High-egg-shedding (> 500 EPG) strategically dewormed horses (183/1357) were treated, on average, three times/year. The planned treatment date was already exceeded by 72.5% of the high egg-shedders and by 58.1% of the moderate (200-500 EPG) and low egg-shedders (20-199 EPG). Conclusions: S. vulgaris seems to be rare in Germany and no difference in its frequency has yet been found between selectively treated horses and horses receiving treatment in strategic intervals. However, inconsistent parasite control has been observed. Therefore, to minimize the risks for disease, consistent and efficient parasite control should be implemented

Molecular identification of zoonotic and livestock-specific Giardia-species in faecal samples of calves in Southern Germany

Background: Giardia-infection in cattle is often subclinical or asymptomatic, but it can also cause diarrhoea. The livestock-specific species Giardia bovis is the most frequently observed in cattle, however, the two zoonotic species Giardia duodenalis and Giardia enterica have also been found. Therefore calves are thought to be of public health significance. The aim of this study was to obtain current data about the frequency of the different Giardia-species in calves in Southern Germany. Findings: Faecal samples of calves (diarrhoeic and healthy) in Southern Germany, diagnosed Giardia-positive by microscopy, were characterised by multi-locus PCR and sequencing. Of 152 microscopically Giardia-positive samples 110 (72.4%) were positive by PCR and successfully sequenced. G. bovis (Assemblage E) was detected in 101/110 (91.8%) PCR-positive samples, whilst G. duodenalis (Assemblage A) was detected in 8/110 (7.3%) samples and a mixed infection with G. duodenalis and G. bovis (Assemblage A+E) was identified in 1/110 (0.9%) samples. The sub-genotypes A1, E2 and E3 were identified with the beta-giardin and the glutamate dehydrogenase genes. In the majority of diarrhoeic faecal samples a co-infection with Cryptosporidium spp. or Eimeria spp. was present, however, there were some in which G. bovis was the only protozoan pathogen found. Conclusions: The results suggest that there is potentially a risk for animal handlers as calves in Southern Germany are, at a low percentage, infected with the zoonotic species G. duodenalis. In addition, it was found that G. bovis was the only pathogen identified in some samples of diarrhoeic calves, indicating that this parasite may be a contributing factor to diarrhoea in calves

Repeatability of strongyle egg counts in naturally infected horses

The selective treatment of horses is used to decrease the number of anthelmintic treatments by only treating a proportion of animals in the population. One way to select animals for treatment is to identify low and high egg-shedders using faecal egg counts (FEC); then to treat only the high egg-shedders. The value of this method is enhanced if differences among individuals in the level of egg-shedding remain consistent over time. One way to assess the stability of the rankings of animals over time is to measure the repeatability which is defined as the variance between horses divided by the total variance. The repeatability varies between 0 (no consistency in the values) to 1 (perfect consistency). To determine the repeatability of egg-shedding in naturally infected horses over time, 2637 FEC and raw egg counts (REC; i.e. originally counted eggs without multiplication factor) from 303 horses were analysed. The distribution of FEC was more overdispersed than a Poisson distribution. Therefore, a negative-binomial model was used. The within-horse-repeatability of RECs was 0.52. In a second analysis, we excluded horses that were treated with anthelmintic drugs during the study by eliminating all REC within the egg-reappearance-period. Here, the within-horse-repeatability was very similar at 0.53. The results show that egg-shedding of individual horses stays fairly consistent over time. They also show that animals which shed relatively high numbers of nematode eggs can be identified and targeted for treatment

Strongyle infections and parasitic control strategies in German horses ― a risk assessment

Background: As a consequence of the increasing levels of anthelmintic resistance in cyathostomes, new strategies for equine parasite control are being implemented. To assess the potential risks of these, the occurrence of strongyles was evaluated in a group of 1887 horses. The distribution of fecal egg counts (FECs), the frequency of anthelmintic drug use, and the deworming intervals were also analyzed. Between June 2012 and May 2013, 1887 fecal samples from either selectively or strategically dewormed horses were collected at 195 horse farms all over Germany and analyzed quantitatively with a modified McMaster technique. All samples with FEC >= 20 eggs per gram (EPG) were subjected to coproculture to generate third-stage larvae (LIII) for species differentiation. Results: Egg counts were below the limit of detection (20 EPG) in 1046 (55.4%) samples and above it in 841 (44.6%) samples. Strongylus vulgaris larvae were identified in two of the 841 positive samples. Infections with cyathostomes were found on every farm. The most frequently applied anthelmintic was ivermectin (788/50.8%), followed by pyrantel (336/21.6%). The mean time since last treatment was 6.3 months. High-egg-shedding (> 500 EPG) strategically dewormed horses (183/1357) were treated, on average, three times/year. The planned treatment date was already exceeded by 72.5% of the high egg-shedders and by 58.1% of the moderate (200-500 EPG) and low egg-shedders (20-199 EPG). Conclusions: S. vulgaris seems to be rare in Germany and no difference in its frequency has yet been found between selectively treated horses and horses receiving treatment in strategic intervals. However, inconsistent parasite control has been observed. Therefore, to minimize the risks for disease, consistent and efficient parasite control should be implemented