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.

Prevalence of pasture-associated metazoal endoparasites in Bavarian dairy goat herds and farmers' approaches to parasite control.

The majority of dairy goat farms in Bavaria operate pasture-based systems. Endoparasites are therefore a common problem affecting health and productivity of these herds. Pooled faecal samples from 37 commercial dairy goat farms in Bavaria were examined by modified McMaster, flotation, sedimentation and Baermann funnel techniques. In addition, a questionnaire was used to gather information on farmers' perceptions and parasite management efforts. The average trichostrongyle faecal egg count across the 37 farms was 620 epg, with a median of 450 epg (1st quartile: 135 epg; 3rd quartile: 930 epg; range: < 30 to 3090 epg). Fasciola hepatica eggs were detected on four farms, Moniezia expansa eggs on one, Muellerius capillaris larvae on 13 and Dicrocoelium dendriticum eggs in none of the samples. Following coproculture third stage larvae of trichostrongyle species were identified morphologically. Sufficient larval numbers were obtained from samples from 23 farms. Haemonchus spp. was the most abundant larval genus and accounted for 30.4% of all larvae examined (n = 4868), followed by Trichostrongylus spp. (27.5%), Teladorsagia spp. (21.8%) and Oesophagostomum spp./Chabertia spp. (19.0%; these two genera were not differentiated). Further nematodes were identified according to their egg morphology: Nematodirus spp were present on nine farms, Skrjabinema spp. on nine, Trichuris spp. on five and Strongyloides spp. were not detected in any of the samples. The questionnaire results indicated a widespread lack of farmer awareness of appropriate parasite management and treatment measures. Farmer and veterinary education is therefore important to avoid future resistance problems caused by under-dosing or inappropriate treatments.

Fascioloides magna--epizootiology in a deer farm in Germany.

After initial observations of suspicious cases in 2009, the occurrence of Fascioloides (F.) magna in deer of a deer farm located in northeastern Bavaria, Germany, at the border to the Czech Republic was confirmed in autumn 2011. In March 2012, the deer were treated for fascioloidosis with triclabendazole. To monitor the epizootiology of fascioloidosis in the farm, 80-100 faecal samples were examined for Fascioloides eggs at monthly intervals from June 2012 to June 2013 inclusive. In addition, livers of 27 red deer and one sika deer collected during winter 2012/2013 were examined for gross lesions suspicious for F. magna infection and 21 of the 28 livers were dissected for F. magna recovery. Fascioloides eggs were recorded in 63 (4.9%) of 1280 faecal samples (range 0.4 to 355 eggs per gram). Both, number of Fascioloides-egg positive samples and egg counts were low during the first eight months of the study but increased notably since February 2013. While Fascioloides egg-positive faecal samples were obtained from red deer (46/948,4.9%) and fallow deer (17/166, 10.2%), no Fascioloides eggs were demonstrated in the 166 samples obtained from sika deer. Livers of five red deer and the sika deer showed gross lesions characteristic for fascioloidosis, and F. magna were recovered from three of the five affected red deer livers (range, five to seven flukes). Results of this study confirm that F. magna is endemic in the deer farm, and measures should be implemented to minimize the transmission of the parasite.

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.

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

BACKGROUND: 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. RESULTS: 1564 samples were analysed for the three pathogens using microscopical methods. Giardia spp. was detectable in 112/1564 samples (7.2%). The mean age was 46.5 days and the odds of being infected with Giardia spp. increased slowly up to 8 times from about 12 days to 30 days of age. There appeared to be no seasonal influence on the frequency of Giardia spp. A mono-infection with Giardia spp. was diagnosed in 46 calves (2.9%) whereas 15 calves (1.0%) had a mixed-infection with Cryptosporidium spp. and 51 calves (3.3%) with Eimeria spp. Cryptosporidium spp. and Eimeria spp. could be detected in 646/1564 samples (41.3%) and 208/1564 samples (13.3%), respectively, with a mean age of 11.3 and 55.0 days, respectively. The odds of being infected with Cryptosporidium spp. increased up to 4.5 times until an age of 10 days. After that the odds decreased continuously and was approaching zero at about 30 days. The odds of being infected with Eimeria spp. increased continuously up to 30 times from about 20 days to 60 days of age. There appeared to be no significant seasonal influence on the frequency of Cryptosporidium spp.; but there was one for Eimeria spp.: the odds of being infected with Eimeria spp. in March and April decreased by about half and increased up to 2.3 times between July and September. Additionally, as requested by the veterinarians, 1282 of those samples were analysed for E. coli, Rota-, Coronavirus and Cryptosporidium spp. using an ELISA. Obtained frequencies for these pathogens were 0.9%, 37.8%, 3.4% and 45.3% with a mean age of 24.8 days, 12.1 days, 9.0 days and 12.1 days, respectively. CONCLUSIONS: The results indicate that in Southern Germany in addition to Eimeria spp., Giardia spp. seems to play a contributing role in diarrhoea in older calves, whereas Cryptosporidium spp. and Rotavirus are mostly relevant in young calves.

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 ß-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.

The accuracy of the FAMACHA-method in detecting anaemia and haemonchosis in goat flocks in Switzerland under field conditions.

In this study, goats from six farms in Central Switzerland were examined for the evaluation of the FAMACHA-method under middle European conditions. Individual faecal egg counts were determined at a 4-week interval for a period of 6 months and the gastrointestinal nematode (GIN) genera were differentiated using larval culture. Simultaneously, the goats were bled for packed cell volume (PCV) determination and scored for anaemia of the conjunctiva according to the FAMACHA-method. The three methods used for evaluating haemonchosis, namely FEC, PCV and FAMACHA-score, were compared to test the FAMACHA-method for its accuracy and efficacy in detecting haemonchosis in Switzerland. PCV and FAMACHA-score correlated significantly during the entire period of 6 months, whereas PCV and FEC correlated significantly in four study months. The FAMACHA-score and FEC correlated significantly in June only. PCV served as the gold standard for evaluating the accuracy of FAMACHA-method in detecting anaemic goats. The sensitivity of FAMACHA in detecting anaemic goats was 93%, using the anaemia criteria cut-offs FAMACHA-categories >or=3 and PCV <22%. The applicability of the method for detecting goats which needed treatment was tested with FEC >300 epg and >600 epg as cut-off values for treatment. The sensitivity of the method for detecting goats which needed a treatment was 76%, with regard to FEC of Haemonchus contortus (treatment cut-offs: FAMACHA >or=3 and FEC >300 epg). The percentage of false negatives (FEC-Hc-portion) was less than 11%. In addition, the use of FAMACHA categories >or=3, as a treatment indicator, revealed that 64% of the animals were recommended for treatment. These results indicate the suitability of FAMACHA as an additional part of an integrated anthelmintic control of goat flocks in Switzerland.

Anthelminthic resistance of Haemonchus contortus in small ruminants in Switzerland and Southern Germany.

Two goat and two sheep flocks have been found to be suspicious of a clinically evident reduced anthelmintic efficacy, i.e. lacking improvement of gastrointestinal disorders, insufficient weight gain and continuing inappetence after anthelmintic treatments. In order to conduct an appropriate evaluation of the efficacy the following trials were performed: the faecal egg count reduction test on the studied goats of the two herds revealed a reduction of the egg-excretion after the eprinomectin-treatment (1 mg/kg BW, pour-on) of 17.4% and 27.5%, respectively, which clearly confirms the occurrence of anthelmintic resistance against eprinomectin in these two herds. The alternatively administered moxidectin-treatment (1 mg/kg BW, pour-on) of one flock resulted in a 99.1% faecal egg count reduction. In both sheep flocks, 30 randomly selected sheep were divided in three groups and each group was treated with a different anthelmintic, according to the instructions for use. The faecal egg count reductions for the various groups treated orally with benzimidazoles were 70.8% and 55.3% (albendazole), 52.4% (fenbendazole) and 47.3% (oxfendazole). The two moxidectin-treated groups (0.2 mg/kg BW, oral) showed an EpG-reduction of 100% and 44.3%, respectively, thus also demonstrating resistance against macrocyclic lactones. Pre- and post-treatment faecal larval cultures revealed Haemonchus contortus as the predominant resistant species.