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Currently, 7 named Sarcocystis species infect cattle: Sarcocystis hirsuta , S. cruzi , S. hominis , S. bovifelis , S. heydorni , S. bovini and S. rommeli ; other, unnamed species also infect cattle. Of these parasites of cattle, a complete life cycle description is known only for S. cruzi , the most pathogenic species in cattle. The life cycle of S. cruzi was completed experimentally in 1982, before related parasite species were structurally characterized, and before the advent of molecular diagnostics; to our knowledge, no archived frozen tissues from the cattle employed in the original descriptions remain for DNA characterization. Here, we isolated DNA from a paraffin-embedded kidney of a calf experimentally infected with S. cruzi in 1980; we then sequenced portions of 18S rRNA, 28S rRNA, COX1 and Acetyl CoA genes and verified that each shares 99–100% similarity to other available isolates attributed to S. cruzi from naturally infected cattle. We also reevaluated histological sections of tissues of calves experimentally infected with S. cruzi in the original description, exploiting improvements in photographic technology to render clearer morphological detail. Finally, we reviewed all available studies of the life cycle of S. cruzi , noting that S. cruzi was transmitted between bison (Bison bison) and cattle (Bos taurus) and that the strain of parasite derived from bison appeared more pathogenic than the cattle strain. Based on these newfound molecular, morphological and physiological data, we thereby redescribed S. cruzi and deposited reference material in the Smithsonian Museum for posterity. [ABSTRACT FROM AUTHOR]

New ideas for diagnostics in clinical parasitology are needed to overcome some of the difficulties experienced in the widespread adoption of detection methods for gastrointestinal parasites in livestock. Here we provide an initial evaluation of the performance of a newly developed automated device (Telenostic) to identify and quantify parasitic elements in fecal samples. This study compared the Telenostic device with the McMaster and Mini-FLOTAC for counting of strongyle eggs in a fecal sample. Three bovine fecal samples were examined, in triplicate, on each of the three fecal egg-counting devices. In addition, both manual (laboratory technician) and automated analysis (image analysis algorithm) were performed on the Telenostic device to calculate fecal egg counts (FEC). Overall, there were consistent egg counts reported across the three devices and calculation methods. The Telenostic device compared very favourably to the Mini-FLOTAC and McMaster. Only in sample C, a significant difference (P < 0.05) was observed between the egg counts obtained by Mini-FLOTAC and by the other methods. From this limited dataset it can be concluded that the Telenostic-automated test is comparable to currently used benchmark FEC methods, while improving the workflow, test turn-around time and not requiring trained laboratory personnel to operate or interpret the results. [ABSTRACT FROM AUTHOR]

As genomic research continues to improve our understanding of the genetics of anthelmintic drug resistance, the revolution in DNA sequencing technologies will provide increasing opportunities for large-scale surveillance for the emergence of drug resistance. In most countries, parasite control in cattle and bison has mainly depended on pour-on macrocyclic lactone formulations resulting in widespread ivermectin resistance. Consequently, there is an increased interest in using benzimidazole drugs which have been used comparatively little in cattle and bison in recent years. This situation, together with our understanding of benzimidazole resistance genetics, provides a practical opportunity to use deep-amplicon sequencing to assess the risk of drug resistance emergence. In this paper, we use deep-amplicon sequencing to scan for those mutations in the isotype-1 β-tubulin gene previously associated with benzimidazole resistance in many trichostrongylid nematode species. We found that several of these mutations occur at low frequency in many cattle and bison parasite populations in North America, suggesting increased use of benzimidazole drugs in cattle has the potential to result in widespread emergence of resistance in multiple parasite species. This work illustrates a post-genomic approach to large-scale surveillance of early emergence of anthelmintic resistance in the field. [ABSTRACT FROM AUTHOR]

Bovine trichomoniasis is a notifiable, reproductive disease of cattle caused by the parasite Tritrichomonas foetus. Culturing with modified Diamond's medium (MDM) is required to increase the low number of organisms received from a preputial sample, but is limited in application to remote areas as it requires continuous cold chain storage. This study utilized lyophilization to sustain the viability of MDM during transport in lieu of a continuous cold chain. All lyophilized MDM was able to sustain T. foetus after storage for 42 days at 24 °C, and the results demonstrated that lyophilized MDM was equally as viable as refrigerated liquid MDM. Storage of lyophilized MDM at room temperature for 1 and 7 days did not impact T. foetus yield, both with and without exposure to light. A limitation of the lyophilized MDM was demonstrated with a significant decrease in T. foetus yield when the media was stored at 37 and 58 °C. The lyophilization of MDM provides a robust method of transporting and storing medium prior to reconstitution and inoculation, for use in T. foetus diagnosis and surveillance in remote areas. [ABSTRACT FROM AUTHOR]

The epidemiology of trematode infections in cattle was investigated within highland and lowland areas of Iringa Rural District, in southern Tanzania. Fecal samples were collected from 450 cattle in 15 villages at altitudes ranging from 696 to 1800 m above the sea level. Freshwater snails were collected from selected water bodies and screened for emergence of cercariae. The infection rates in cattle were Fasciola gigantica 28⋅2%, paramphistomes 62⋅8% and Schistosoma bovis 4⋅8%. Notably, prevalence of trematode infections in cattle was much higher in highland (altitude > 1500 m) as compared with lowland (altitude < 1500 m) areas and was statistically significant (P-value = 0⋅000) for F. gigantica and paramphistomes but not for S. bovis. The snails collected included Lymnaea natalensis, Bulinus africanus, Bulinus tropicus, Bulinus forskali, Biomphalaria pfeifferi, Melanoides tuberculata and Bellamya constricta with a greater proportion of highland (75%) than lowland (36%) water bodies harbouring snails. Altitude is a major factor shaping the epidemiology of F. gigantica and paramphistomes infections in cattle in Iringa Rural District with greater emphasis upon control needed in highland areas. [ABSTRACT FROM AUTHOR]

Fasciola hepatica is a pathogenic trematode parasite of ruminants with a global distribution. Here, we briefly review the current epidemiology of bovine fasciolosis in Europe and discuss the progress made over the last decade in the diagnosis, impact on production and prediction of F. hepatica in cattle. Advances in diagnosis have led to significantly improved coprological and serological methods to detect presence of infection. Diagnostic test results have been correlated with intensity of infection and associated production losses, unravelling the impact on carcass weight and milk yield in modern cattle production systems. The economic impact of fasciolosis may, however, go beyond the direct impacts on production as evidence shows that F. hepatica can modulate the immune response to some co-infections. Control of bovine fasciolosis remains hampered by the limitations of the currently available flukicidal drugs: few drugs are available to treat dairy cows, many have low efficacies against juvenile stages of F. hepatica and there is evidence for the development of drug resistance. This makes research into the prediction of risk periods, and thus the optimum application of available drugs more pertinent. In this field, the recent research focus has been on understanding spatial risk and delivering region-specific spatial distribution maps. Further advances in epidemiological and economic research on bovine fasciolosis are expected to deliver farm-specific economic assessments of disease impact, to leverage non-chemotherapeutic management options and to enhance a more targeted use of anthelmintics. [ABSTRACT FROM AUTHOR]

The intra-erythrocytic protozoan Babesia bovis is an economically important pathogen that causes an acute and often fatal infection in adult cattle. Babesiosis limitation depends on the early activation of macrophages, essential cells of the host innate immunity, which can generate an inflammatory response mediated by cytokines and nitric oxide (NO). Herein, we demonstrate in bovine macrophages that lipids from B. bovis attenuated R1A strain (LA) produced a stronger NO release, an early TNFα mRNA induction and 2-fold higher IL-12p35 mRNA levels compared to the lipids of virulent S2P strain (LV). Neither LA nor LV induced anti-inflammatory IL-10. Regarding signalling pathways, we here report that LA induced a significant phosphorylation of p38 and extracellular signal-regulated kinases 1 and 2 (ERK1/2) whereas LV only induced a reduced activation of ERK1/2. Besides, NF-κB was activated by LA and LV, but LA produced an early degradation of the inhibitor IκB. Interestingly, LV and the majority of its lipid fractions, exerted a significant inhibition of concanavalin A-induced peripheral blood mononuclear cell proliferation with respect to LA and its corresponding lipid fractions. In addition, we determined that animals infected with R1A developed a higher increase in IgM anti-phosphatidylcholine than those inoculated with S2P. Collectively, S2P lipids generated a decreased inflammatory response contributing to the evasion of innate immunity. Moreover, since R1A lipids induced a pro-inflammatory profile, we propose these molecules as good candidates for immunoprophylactic strategies against babesiosis. [ABSTRACT FROM AUTHOR]

Neospora caninum is an Apicomplexan protozoan that has the dog as a definitive host and cattle (among other animals) as intermediate hosts. It causes encephalopathy in dogs and abortion in cows, with significant loss in worldwide livestock. As any Apicomplexan, the parasite invades the cells using proteins contained in the phylum-specific organelles, like the micronemes, rhoptries and dense granules. The aim of this study was the characterization of a homologue (denominated NcMIC2-like1) of N. caninum thrombospondin-related anonymous protein (NcMIC2), a micronemal protein previously shown to be involved in the attachment and connection with the intracellular motor responsible for the active process of invasion. A polyclonal antiserum raised against the recombinant NcMIC2-like1 functional core (thrombospondin and integrin domains) recognized the native form of NcMIC2-like1, inhibited the in vitro invasion process and localized NcMIC2-like1 at the apical complex of the parasite by confocal immunofluorescence, indicating its micronemal localization. The new molecule, NcMIC2-like1, has features that differentiates it from NcMIC2 in a substantial way to be considered a homologue†. [ABSTRACT FROM PUBLISHER]

SUMMARYNeospora caninumis a cyst-forming parasite that causes abortion in cattle. Despite this parasite's ubiquitous distribution and wide host range, the number of N. caninumisolates obtained to date is limited. In vitroisolation of the parasite is arduous and often unsuccessful. In addition, most isolates have been obtained from clinically affected hosts and therefore could be biased towards more virulent isolates. In this report, an improved isolation approach from transplacentally infected newborn calves was undertaken and 9 new isolates were obtained. Moreover, a microsatellite technique was applied to investigate the genetic diversity of these isolates. Most isolates showed specific genetic profiles. However, the Nc-Spain10 isolate was identical to the previously described Nc-Spain1H isolate and Nc-Spain3H was identical to Nc-Spain4H. These isolates were likely to have identical genotypes because they were isolated from distinct calves of the same herd. Future pathogenic characterization of these isolates will contribute to the investigation of the relationship between isolate virulence and the outcome of infection, as well as other epidemiological features, such as transmission. [ABSTRACT FROM AUTHOR]

SUMMARYTheileria parvais an intracellular protozoan parasite transmitted by ticks that causes a fatal lymphoproliferative disease of cattle known as East Coast Fever. Vaccination against the disease currently relies on inoculation of the infective sporozoite stage of the parasite and simultaneous treatment with long-acting formulations of oxytetracycline. Sporozoites are maintained as frozen stabilates of triturated infected ticks and the method requires accurate titration of stabilates to determine appropriate dose rates. Titration has traditionally been undertaken in cattle and requires large numbers of animals because of individual variation in susceptibility to infection. An alternative tissue culture-based method is laborious and time consuming. We have developed a flow cytometric method for quantifying the infectivity of sporozoite stabilates in vitrobased on the detection of intracellular parasite antigen. The method allows clear identification of parasitized cells with a high degree of sensitivity and specificity. Analysis of infected cells between 48 and 72?h post-infection clearly defines the potential transforming capability of different stabilates. [ABSTRACT FROM AUTHOR]