Ultrasonography screening of hepatic cystic echinococcosis in sheep flocks used for evaluating control progress in a remote mountain area of Hejing County, Xinjiang.

BACKGROUND: Although ultrasonography (US) has been widely used in the diagnosis of human diseases to monitor the progress of cystic echinococcosis (CE) control, the screening method for hepatic CE in sheep flocks requires adjustment. In this study, we used a US scanner to screen sheep flocks and evaluated the efficacy of dosing dogs once a year with praziquantel for 7 years from 2014 to 2021. METHODS: All sheep in the three flocks were screened using an ultrasound scanner in 2014 and compared with the prevalence of infection in 2021 in Bayinbuluke, Xinjiang, China. Sheep age was determined using incisor teeth. Cyst activity and calcification were determined using US images. The dogs were dewormed with praziquantel once a year to control echinococcosis in the community. RESULTS: Three flocks had 968 sheep in 2014, with 13.22%, 22.62%, 18.7%, 27.27%, 11.88%, and 6.3% of sheep aged 1, 2, 3, 4, 5, and ≥ 6 years old, respectively. US scanning revealed that the overall CE prevalence was 38.43% (372/968), with active cysts and calcified cysts present in 9.40% (91/968) and 29.02% (281/968) of the sheep, respectively. For the young sheep aged 1 and 2 years, the prevalence of active and calcified cysts was: 1.56% and 0.91%, and 10.94% and 18.72%, respectively. Approximately 15.15% and 16.52% of the 4- and 5-year-old sheep, respectively, harbored active cysts. There was no significant difference in the infection rates of sheep between 2014 and 2021 (P > 0.05). CONCLUSIONS: US is a practical tool for the field screening of CE in sheep flocks. One-third of the sheep population in the flocks was 1-2 years old, and these sheep played a very limited role in CE transmission, as most of the cysts were calcified. Old sheep, especially culled aged sheep, play a key role in the transmission of CE. Dosing dogs once a year did not affect echinococcosis control.

Comparative analysis of host immune responses to Hydatid cyst in human and ovine hepatic cystic Echinococcosis.

BACKGROUND: Hydatid disease is caused by the larval stages of the canine tapeworm Echinococcus granulosus. It is one of the most critical helminthic diseases, representing worldwide public health and socio-economic concern. AIM: This study aimed to investigate the expression of apoptosis and immune response within hepatic tissues of humans and sheep infected with the Hydatid cyst. METHODS: Paraffin-embedded tissue was prepared from each tissue sample and used for histopathological examination by Haematoxylin- Eosin. Also, toluidine blue staining was used for mast cell detection, while an immunohistochemical study was performed to assess CD3 T lymphocytes, CD4 helper T lymphocytes, CD8 cytotoxic T lymphocytes, CD20 memory B lymphocytes, CD68 macrophage, and caspase-3 antibodies. RESULTS: The histological examination revealed significant changes, including the infiltration of inflammatory cells, predominantly lymphocytes with scattered giant cells, necrotic hepatic tissue, and fibrosis. Toluidine blue stain revealed a higher number of mast cells (5 cells/field) in humans compared to sheep (3.6 cells/field). The immunohistochemical analysis confirmed that the CD3 were the most predominant inflammatory cell in the hepatic tissue of humans (intensive 70%), and sheep (moderate 38.47%). Caspase-3 was observed in all samples in different grades and mostly in human liver tissue. CONCLUSION: This data could aid in recognizing immunological markers for differentiating disease progression, as well as enhance the understanding of local immune responses to cystic Echinococcosis (CE). The findings could provide preliminary data for future studies on immune responses associated with Hydatid cysts.

Untargeted metabolomics to discriminate liver and lung hydatid cysts: Importance of metabolites involved in the immune response.

The Echinococcus granulosus sensu lato species complex is responsible for the neglected zoonotic disease known as cystic echinococcosis (CE). Humans and livestock are infected via fecal-oral transmission. CE remains prevalent in Western China, Central Asia, South America, Eastern Africa, and the Mediterranean. Approximately one million individuals worldwide are affected, influencing veterinary and public health, as well as social and economic matters. The infection causes slow-growing cysts, predominantly in the liver and lungs, but can also develop in other organs. The exact progression of these cysts is uncertain. This study aimed to understand the survival mechanisms of liver and lung CE cysts from cattle by determining their metabolite profiles through metabolomics and multivariate statistical analyses. Non-targeted metabolomic approaches were conducted using quadrupole-time-of-flight liquid chromatography/mass spectrometry (LC-QTOF-MS) to distinguish between liver and lung CE cysts. Data processing to extract the peaks on complex chromatograms was performed using XCMS. PCA and OPLS-DA plots obtained through multiple statistical analyses showed interactions of metabolites within and between groups. Metabolites such as glutathione, prostaglandin, folic acid, and cortisol that cause different immunological reactions have been identified both in liver and lung hydatid cysts, but in different ratios. Considering the differences in the metabolomic profiles of the liver and lung cysts determined in the present study will contribute research to enlighten the nature of the cyst and develop specific therapeutic strategies.

Computed tomographic appearance of canine hepatic alveolar echinococcosis.

Alveolar echinococcosis (AE) is caused by Echinococcus multilocularis, affecting dogs as accidental intermediate hosts. CT is increasingly used for abdominal imaging in small animals, providing valuable information, particularly for large masses and limited ultrasound accessibility. This study describes CT findings of hepatic lesions in 13 dogs with AE. All cases displayed well-defined cavitary lesions in the liver. Lesions showed minimal to no contrast uptake in the periphery, no uptake centrally, irregular internal walls, and soft tissue septa. Eight of 13 cases exhibited large cavitary masses (mean diameter 18.7 cm) with thick walls and feathery mineralization. Three of 13 cases had multiple smaller cavitary lesions with thin walls and without mineralization (mean diameter 8.4 cm). Two of 13 cases presented with both lesion types. These findings suggest two typical CT appearances correlated with AE: large thick-walled- and smaller thin-walled lesions. These groups may represent different stages of AE, with smaller lesions merging and progressing into larger ones. In conclusion, CT provides valuable information in evaluating hepatic lesions in dogs with AE. Large cavitary, thick-walled liver lesions with feathery wall mineralization, irregular inner margination, septation, and no central contrast uptake strongly indicate hepatic AE in dogs, differentiating it from other masses.

ULTRASOUND-GUIDED PERCUTANEOUS TREATMENT OF HEPATIC HYDATIDOSIS IN TWO RED-SHANKED DOUC LANGURS (PYGATHRIX NEMAEUS).

Hydatid disease caused by Echinococcus ortleppi is a major cause of morbidity and mortality for critically endangered captive langurs in northern Vietnam. The most common sites for hydatid cyst development are the liver and the lungs. Chemotherapy trials with albendazole alone or in combination with praziquantel in these langurs had varying results and in most cases were ineffective. Ultrasound-guided percutaneous aspiration of cystic fluid followed by instillation and re-aspiration of a scolicidal agent (PAIR technique), has gained importance in the treatment of active hepatic cysts in humans and in many cases is preferred over surgical and endoscopic approaches. The PAIR technique was used in two red-shanked douc langurs (Pygathrix nemaeus) for the treatment of unilocular active hepatic cysts. The technique was found to be fairly easy to perform, safe, and effective and should be a useful treatment tool for hepatic hydatidosis in langurs and other nonhuman primate species.

Ultrasonographic verification of hepatic hydatidosis in a female dromedary camel: a case report.

This report describes for the first time, the antemortem diagnosis of hydatidosis in dromedary camel based on the WHO informal working groups on echinococcosis guidelines of echinococcosis classification. The case was admitted at the University Veterinary Hospital, Qassim University, Saudi Arabia, with a history of progressive weight loss and decreased appetite for the past 4 months. Alterations in hematobiochemical parameters included leukopenia, neutropenia, decreased hematocrit percent, red blood cells count and hemoglobin concentration, hypoproteinemia, hypoalbuminemia, hyperglobulinemia, hyperglycemia and azotemia. Ultrasonographically, multiple cysts were imaged within the hepatic tissue containing anechoic fluid and fibrin tags. Ultrasound-guided aspiration of a cyst revealed a clear non-turbid fluid. Ultrasonographic diagnostic is recommended for the work-up of cystic lesions of camel liver suspected to be due to Echinococcus granulosus.

Diagnosis, treatment, and outcome of four dogs with alveolar echinococcosis in the northwestern United States.

OBJECTIVE: To describe the clinical disease, diagnostic findings, medical management, and outcome in dogs with alveolar echinococcosis (AE). ANIMALS: 4 dogs with naturally occurring AE. PROCEDURES: Medical records were retrospectively reviewed from 2020 to 2022 to identify dogs diagnosed with AE. Signalment, case history, clinical signs, imaging and pathological laboratory findings, treatment, and clinical outcome were reported. RESULTS: All dogs developed systemic clinical illness and weight loss. Abdominal ultrasonography revealed multifocal to coalescent cystic masses of variable size distributed throughout the liver in all cases. Evaluation of aspirated hepatic cyst contents included membranous parasite structures and calcareous corpuscles. Echinococcus multilocularis was confirmed via PCR from hepatic cyst fluid in 3 of 4 cases. Treatment included systemic benzimidazole and praziquantel administration, 1 or more instances of ultrasound-guided cyst drainage in all cases, with ethanol ablation (percutaneous aspiration-injection-reaspiration) in 2 cases, and surgical resection in 1 case. Two of 4 dogs were euthanized within 5 months of diagnosis. One of these dogs was necropsied and had nearly complete obliteration of the hepatic parenchyma by multilocular cystic masses. One dog is still alive, and 1 dog has been lost to follow-up. CLINICAL RELEVANCE: This series of cases highlighted the diagnostic findings and therapeutic intervention in 4 dogs with AE. This was the first report of medical management incorporating the percutaneous aspiration-injection-reaspiration method used in humans. Reports of canine AE are rare in the US, so this series serves to help raise awareness of hepatic AE in the northwestern US.

Response patterns in adventitial layer of Echinococcus granulosus sensu stricto cysts from naturally infected cattle and sheep.

Cystic echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus granulosus sensu lato. The disease is characterized by the development of cystic structures inside viscera of the intermediate host, mainly liver and lungs. These cysts are formed by three layers: germinal, laminated, and adventitial layer, the latter being the local host immune response. Metacestodes that develop protoscoleces, the infective stage to the definitive host, are termed fertile, whereas cysts that do not produce protoscoleces are termed non-fertile. Sheep usually harbor fertile cysts while cattle usually harbor non-fertile cysts. Adventitial layers with fibrotic resolution are associated to fertile cysts, whereas a granulomatous reaction is associated with non-fertile cysts. The aim of this study was to analyze cellular distribution in the adventitial layer of fertile and non-fertile E. granulosus sensu stricto cysts found in liver and lungs of cattle and sheep. A total of 418 cysts were analyzed, 203 from cattle (8 fertile and 195 non-fertile) and 215 from sheep (64 fertile and 151 non-fertile). Fertile cysts from cattle showed mixed patterns of response, with fibrotic resolution and presence of granulomatous response in direct contact with the laminated layer, while sheep fertile cysts always displayed fibrotic resolution next to the laminated layer. Cattle non-fertile cysts display a granulomatous reaction in direct contact with the laminated layer, whereas sheep non-fertile cysts display a granulomatous reaction, but in direct contact with the fibrotic resolution. This shows that cattle and sheep cystic echinococcosis cysts have distinct local immune response patterns, which are associated to metacestode fertility.

Prevalence of Liver Hydatidosis and Its Economic Significance in Sheep Slaughtered in a Private Abattoir in Konya

Objective: This study aimed to determine the prevalence of liver hydatidosis in sheep slaughtered in a private slaughterhouse in Konya and to estimate the economic loss incurred because of the disease. Methods: The study was conducted over a period of 12 months between 1 June 2018 and 31 May 2019. Given that the aim of this investigation was to determine the prevalence of liver hydatidosis, only the livers of 41,002 sheep were examined for hydatid cysts. Results: The liver of 810 (1.97%) sheep was found to be infected with hydatid cysts during the study period. The infection rate was determined as 5.34% in animals older than one year of age and 1.68% in animals less than one year of age. Regardless of the age group, the highest infection rate was found in autumn (3.34%), while the lowest infection rate was seen in spring (0.84%). In the sheep, the highest infection rate was in December (17.2%), and in lambs, it was in June (2.9%). On the other hand, the lowest infection rate in sheep was observed in November (1.8%), while the lowest infection rate in lambs was found in April (0.7%). The total economic loss incurred due to the annihilated livers was estimated as 36,450 TL (6.417$). Regardless of the number of cysts and degree of infection, the infected livers were completely discarded. The economic loss incurred due to the discarded livers was estimated by considering the 2019 offal prices. Conclusion: Based on the data obtained from this study, it could be concluded that hydatidosis still exists in Konya as well as throughout Turkey and that it causes serious economic loss.

Relationship between hepatic grayish-white solid nodules in horses imported from Canada and larval Echinococcus multilocularis infection.

Histopathological and genetic examinations were conducted on grayish-white solid hepatic nodules in 150 horses imported from Canada, in order to investigate larval Echinococcus multilocularis infection. Ten of the 150 horses (6.7%) were diagnosed with alveolar hydatid disease. The sequences of the mitochondrial cytochrome b genes obtained from all 10 polymerase chain reaction positive samples had 99 to 100% identity with the European haplotype E1 of E. multilocularis. Therefore, we concluded that the infections likely originated in Canada.

Relation entre les nodules hépatiques solides blanc-grisâtre trouvés chez des chevaux importés du Canada et l'infection larvaire à Echinococcus multilocularis . Des examens histopathologiques et génétiques ont été effectués sur des nodules hépatiques solides blanc-grisâtre observés chez 150 chevaux importés du Canada afin d'étudier l'infection larvaire à Echinococcus multilocularis. Dix des 150 chevaux (6,7 %) ont reçu un diagnostic de maladie hydatique alvéolaire. Les séquences des gènes mitochondriaux du cytochrome b obtenus à partir des 10 échantillons positifs par réaction d'amplification en chaîne par la polymérase ont montré une identité de 99 à 100 % avec l'haplotype européen E1 d'E. multilocularis. L'haplotype d'E. multilocularis obtenu à partir de cette étude suggère que les infections sont probablement originaires du Canada.(Traduit par Dr Serge Messier).

Percutaneous aspiration-injection-reaspiration (PAIR) for the treatment of abdominal cysts: Initial report in sheep and goat.

Percutaneous aspiration-injection-reaspiration (PAIR), also called sclerotherapy, is a minimally invasive, inexpensive and safe technique for the treatment of abdominal cysts in humans. A study was planned to evaluate the feasibility of this procedure in the management of abdominal cysts in sheep and goat. Adult ewes (n = 5) and one doe (n = 1) found to have abdominal cysts (one cyst/animal) on repeated survey ultrasonography (USG) were included in the study. The animals were restrained in standing position. A hypodermic needle (G-18) securely attached to a 10-mL Dispovan syringe was carefully passed under ultrasound guidance into the abdominal cyst in all these animals. Depending on the size of the cyst, 1.0-5.5 mL fluid was aspirated, and 0.5-2.0 mL of 20% hypertonic saline solution infused. The needle was thereafter kept in situ for 10 min. The maximum possible volume of the cyst content was reaspirated and the needle withdrawn. On day 7, sclerotherapy was repeated in five animals showing no appreciable reduction in cyst size by USG. USG was repeated on days 30 and 90. All the cysts except one responded to PAIR during this period. From this study it can be concluded that sclerotherapy using hypertonic saline (20%) is a minimally invasive, inexpensive, effective and safe interventional ultrasonographic technique for the treatment of abdominal cysts in sheep and goats. However, the procedure needs further evaluation after using different sclerotic agents of varying concentrations and duration of their retention in the cysts in a sufficient number of animals with cysts.

A study on causes of cattle liver condemnation at an abattoir in Omdurman area, Khartoum State, Sudan.

BACKGROUND: Information obtained from abattoirs on the causes of liver condemnation is important in preventing the spread of diseases and for promoting food security. The current study reviews three years (2009 to 2011) postmortem inspection records of cattle slaughtered at an abattoir in Omdurman, Khartoum State, Sudan. The aim was to determine the prevalence of diseases and conditions that lead to liver condemnation. RESULTS: From a total of 234,175 cattle slaughtered, 8,910 (3.8%) livers were condemned due to several diseases/conditions mainly fasciolosis, cysticercosis, necrosis, abscess, calcification, hemorrhages, liver cirrhosis, hydatidosis, and other miscellaneous causes. Collectively, fasciolosis was the leading cause of liver condemnation and was responsible for 51.6 % of total liver condemnations followed by necrosis (18.6%), and cysticercosis (13.5%). CONCLUSIONS: Because of their zoonotic nature, the observed high frequency of some detected diseases/conditions is thought to pose a public health risk among consumers. This survey could be used as a regional baseline for future monitoring of control programmers against these liver diseases.

Evaluation of the prevalence of Echinococcus multilocularis in dogs that visit off-leash dog parks in southern Ontario, Canada.

Prior to 2012, Echinococcus multilocularis was not known to occur in any host in Ontario, Canada. However, since that year, five cases of alveolar echinococcosis have been diagnosed in dogs that resided at the western end of Lake Ontario. In addition, E. multilocularis has been shown to be a common infection in wild canids (i.e. coyotes and foxes) across southern Ontario with a high-risk infection cluster in the area surrounding the western shores of Lake Ontario and northern shores of Lake Erie. In regions endemic for E. multilocularis, dog ownership is considered a risk factor for human alveolar echinococcosis. A study was therefore carried out to determine the prevalence of E. multilocularis intestinal infections in dogs within the high-risk infection cluster. From May to November 2018, faecal samples were collected from 477 dogs aged ≥6 months that visited 12 off-leash dog parks in the Halton, Hamilton and Niagara public health units. Faecal samples were analysed via a magnetic capture probe DNA extraction and real-time PCR method for E. multilocularis DNA. Overall, 0% (97.5% CI: 0%-0.80%) of samples tested positive. This result informs preventive recommendations for E. multilocularis infections in dogs in this region.

A Case-Study of the Molecular Diagnosis of Echinococcus multilocularis in Wild Boar with Comments on its Public Health Significance in Turkey.

Echinococcus multilocularis is a parasite species of zoonotic importance which can be fatal to humans and causes Alveolar Echinococcosis (AE). This report describes the development of a cyst from the liver of a wild boar and molecular confirmation of its identification. The cyst material was obtained from the liver of a wild boar killed by hunters. Genomic DNA was extracted from the germinal layer of the cyst material, and 875 bp mitochondrial cytochrome c oxidase subunit I (COI) gene fragment was amplified by PCR and sequenced. A BLAST search matched 100% with published Echinococcus multilocularis sequences. This study confirms the occurrence of E. multilocularis in a wild boar for the first time in Turkey.

Alveolar echinococcosis in a dog in the eastern United States.

An 8-y-old Labrador Retriever was presented to a small animal practice in northern Virginia with a history of recent lethargy. Physical examination findings were unremarkable. Ultrasound revealed several large hepatic masses and multiple smaller masses involving the pancreas. Cytologic findings on fine-needle aspirates of the hepatic masses included inflammation and necrosis with eosinophilic, membranous oval structures consistent with cestode infection. Histopathologic findings for biopsies of these masses included extensive necrosis, inflammation, and PAS-positive hyaline-like membranous material interpreted as metacestode cyst wall. A PCR product was generated from aspirate material using primers specific for Echinococcus multilocularis. Subsequent sequence data were 100% homologous to E. multilocularis NADH dehydrogenase subunit I gene sequences. The dog received daily oral albendazole (10 mg/kg) treatment, but its condition deteriorated, and the dog was euthanized. The dog, born in Mississippi, was brought as a puppy to Virginia with no other travel history. To our knowledge, alveolar echinococcosis has not been reported previously in a dog in the United States; E. multilocularis infection was apparently acquired in the mid-Atlantic region of the United States.

Fasciola hepatica coinfection modifies the morphological and immunological features of Echinococcus granulosus cysts in cattle.

Polyparasitism occurs when animals harbour multiple parasites concomitantly. It is a common occurrence but is generally understudied in wild and domestic animals. Fasciola hepatica and Echinococcus granulosus, which are helminths of ungulates, frequently coinfect cattle. The effects of this particular type of polyparasitism are not well documented. The metacestode of Echinococcus granulosus is surrounded by the adventitial layer, which constitutes the host immune response to the parasite. This layer in cattle is produced by a granulomatous reaction and is involved in echinococcal cyst (EC) fertility. Due to the systemic immune-modulating abilities of Fasciola hepatica, coinfection possibly generates a favourable environment for EC growth. A total of 203 Echinococcus granulosus sensu stricto cysts were found in 82 cattle, of which 42 ECs were found in 31 animals coinfected with Fasciola hepatica. The overall infection intensity was 3 cysts per animal. Coinfection with Fasciola hepatica decreased the mean infection intensity to 1.4 cysts per animal. Regarding EC size, coinfection resulted in smaller ECs (15.91 vs 22.09 mm), especially for infertile lung cysts. The adventitial layer of ECs in coinfected animals lacked lymphoid follicles and palisading macrophages, which are generally hallmarks of the granulomatous immune response. The ECs in coinfected animals had organized laminated layers, whereas those in animals without coinfection did not. Although coinfection was not statistically associated with EC fertility, we did not find fertile cysts in the livers of coinfected animals. We concluded that coinfection with Fasciola hepatica and Echinococcus granulosus has a detrimental effect on ECs, particularly infertile cysts.

Molecular survey on cattle and sheep hydatidosis and first detection of Echinococcus canadensis (G6/G7) in sheep in Turkey.

Larval stage of genus Echinococcus is the causing agent for the zoonotic infection which is life threatening known as Echinococcosis. The purpose of this study was the identification, molecular analysis and characterization of Echinococcus spp. in sheep and cattle. The sampling was done from slaughterhouse of Elazig, Turkey. A total of 85 isolates (sheep, n = 19 and cattle, n = 66) have been collected after slaughtering. Following the gDNA isolation and PCR products of mt-CO1 gene (446 bp) of all the samples were sequenced. Out of 85 isolates, 84 were recognized as Echinococcus granulosus sensu stricto and one sheep isolate was found as Echinococcus canadensis (G6/G7 ) which is identified for the first time in Turkey. However, single nucleotide polymorphism has been observed not only in samples of different animals but also in samples collected from the same cattle. Six liver and three lung hydatid cysts have been detected in cattle. Although no nucleotide differences have been observed in the liver samples, there was single nucleotide polymorphism (C→T) in 40th nucleotide of two lung cysts. As a result of haplotype analysis, 16 haplotypes of E. granulosus s.s. were detected in 66 cattle isolates whereas 7 haplotypes of E. granulosus s.s. were identified in 19 sheep samples.

Alveolar echinococcosis in an Ontario dog resembling an hepatic abscess.

A boxer dog was evaluated because of lethargy, vomiting, and abdominal pain. Ultrasonography revealed multiple cystic structures in the abdomen. Exploratory laparotomy revealed 3 well-encapsulated hepatic masses and abdominal effusion with suppurative inflammation. Collectively, these findings suggested the hepatic masses were most likely abscesses. However, histologic examination of the hepatic masses revealed multi-cystic structures, consistent with alveolar echinococcosis. The diagnosis was confirmed by DNA sequencing. The dog was treated with daily albendazole, but within a few weeks exhibited adverse side effects. After 6 months, the dog's condition deteriorated, and it was euthanized.

Échinococcose alvéolaire ressemblant à un abcès hépatique chez un chien en Ontario. Un chien de race boxer fut évalué à cause de léthargie, vomissements, et douleur abdominale. Une échographie révéla de multiples structures kystiques dans l'abdomen. Une laparotomie exploratoire révéla trois masses hépatiques bien encapsulées et une effusion abdominale avec inflammation suppurative. Collectivement, ces données suggéraient que les masses hépatiques étaient fort probablement des abcès. Toutefois, l'examen histologique des masses hépatiques révéla des structures multi-kystiques, compatibles avec une échinococcose alvéolaire. Le diagnostic fut confirmé par séquençage d'ADN. Le chien fut traité avec de l'albendazole quotidiennement, mais en quelques semaines il montra des signes d'effets adverses. Après 6 mois la condition du chien se détériora et il fut euthanasié.(Traduit par Dr Serge Messier).

Revisiting cyst burden and risk factors for hepatic hydatid disease (Echinococcus granulosus sensu stricto) in Australian beef cattle.

The characteristics and risk factors associated with hepatic Echinococcus granulosus sensu stricto infection (hydatid disease) were investigated in beef cattle slaughtered at an abattoir in eastern Australia. Sampled cattle were sourced from all eastern states, predominantly from regions associated with the Great Dividing Range. Livers and corresponding demographic data were collected from 601 carcasses. Livers were examined for the number, size, viability, and fertility of hydatid cysts. Mixed effects logistic regression was used to evaluate associations of sex, feed-type (grass- or grain-fed), and dentition (age) on hydatid disease. Hydatid cysts were detected in all dentition groups. The most commonly sampled dentition group was zero-tooth cattle (less than 18 months). Twenty-nine percent of infected livers had only one cyst, and 48% of infected livers contained viable cysts. Thirty-seven percent of infected livers had cysts that were 3-10 mm in diameter. The size and number of cysts were positively correlated with age of the animal. Regression analysis showed that the odds of hydatid disease were highest in eight-tooth cattle (>42 months; OR 26.9; 95% CI 11.8-61.6; reference level [ref] zero-tooth). Being grass-fed was also significantly associated with the presence of hydatid disease (total effect; OR 3.0; 95% CI 1.7-5.5; ref grain-fed). Although there was no evidence of a total effect of sex across the study population, males of a given dentition group and feed-type (grass- or grain-fed) were more likely to be infected than respective females. Despite changes in Australian agriculture in the last 30 years, the burden (number, size, and viability of cysts) of hydatid disease in individual infected animals remains similar to previous Australian studies.

Occurrence of Liver Hydatid Cysts in a Donkey and Molecular Characterization of Echinococcus equinus.

Larval tapeworms of Echinococcus granulosus have been viewed as the etiological agent for the zoonotic disease cystic echinococcosis, but the species is a complex readily divided into several species and genotypes. Cystic echinococcosis is an important public health issue. Here, the case of liver hydatid cyst in a donkey and molecular characterization of the cyst is presented. The fluid-filled hydatid cyst materials were obtained from the liver of a necropsied donkey. Genomic DNA was extracted and PCR amplification of mitochondrial 12S rRNA gene as well as partial sequencing of mitochondrial cytochrome c oxidase subunit 1 (COI) gene were performed. All cysts were fertile. Traditional polymerase chain reaction (PCR) amplification of 12S rRNA and COI yielded bands (254 and 446 base pairs, respectively) for all 3 cyst samples. However, partial COI gene sequences were identical to those reported for Echinococcus equinus (formerly E. granulosus genotype G4). Thus E. equinus is still transmitting among the equids in Turkey but the mitochondrial 12S rRNA gene primers may not be sufficient for the molecular characterization of members of the E. granulosus species/genotype complex. Molecular diagnosis must be confirmed by partial COI sequence analysis.