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The present study was conducted to detect the therapeutic effect of Moringa oleifera and Thymus vulgaris oils on hepatic coccidiosis in experimentally infected rabbits. Also, immunomodulatory effect of the two oils was detected. Twenty-four Newzealand rabbits were used in this study and divided into 4 groups; healthy rabbits, experimentally infected rabbits with Eimeria stiedae oocysts, and two infected treated groups (one with moringa (200 mg/kg) and the other with thyme (500 mg/kg) oils). The results showed highly significant reduction in oocysts shedding (P

Eimeria stiedai is an apicomplexan protozoan parasite that invades the liver and bile duct epithelial cells in rabbits and causes severe hepatic coccidiosis, resulting in significant economic losses in the domestic rabbit industry. Hepatic coccidiosis lacks the typical clinical symptoms and there is a lack of effective premortem tools to timely diagnose this disease. Therefore, in the present study we cloned and expressed the two microneme proteins i.e., microneme protein 1 (EsMIC1) and microneme protein 3 (EsMIC3) from E. stiedai and used them as recombinant antigens to develop a serodiagnostic method for an effective diagnosis of hepatic coccidiosis. The cDNAs encoding EsMIC1 and EsMIC3 were cloned and the mRNA expression levels of these two genes at different developmental stages of E. stiedai were determined by quantitative real-time PCR analysis (qRT-PCR). The immunoreactivity of recombinant EsMIC1 (rEsMIC1) and EsMIC3 (rEsMIC3) proteins were detected by Western blotting, and indirect enzyme-linked immunosorbent assays (ELISAs) based on these two recombinant antigens were established to evaluate their serodiagnostic potential. Our results showed that the proteins encoded by the ORFs of EsMIC1 (711 bp) and EsMIC3 (891 bp) were approximately 25.89 and 32.39 kDa in predicted molecular weight, respectively. Both EsMIC1 and EsMIC3 showed the highest mRNA expression levels in the merozoites stage of E. stiedai. Western blotting analysis revealed that both recombinant proteins were recognized by E. stiedai positive sera, and the indirect ELISAs using rEsMIC1 and rEsMIC3 were developed based on their good immunoreactivity, with 100% (48/48) sensitivity and 97.9% (47/48) specificity for rEsMIC1 with 100% (48/48) sensitivity and 100% (48/48) specificity for rEsMIC3, respectively. Moreover, rEsMIC1- and rEsMIC3-based indirect ELISA were able to detect corresponding antibodies in sera at days 6, 8, and 10 post E. stiedai infection, with the highest positive diagnostic rate (62.5% (30/48) for rEsMIC1 and 66.7% (32/48) for rEsMIC3) observed at day 10 post infection. Therefore, both EsMIC1 and EsMIC3 can be used as potential serodiagnostic candidate antigens for hepatic coccidiosis caused by E. stiedai.

Hepatic infection involving a parasite of the family Calyptosporidae was recorded in characiform fish from the Tocantins river in the Brazilian Amazon region. In the present study, an integrated comparative analysis of morphological characteristics, histological and structural traits, and the sequence of a partial fragment of the SSUrRNA gene provides support for the identification of a new calyptosporid species, found parasitising the hepatic tissue of the fish Triportheus angulatus, collected from the Tocantins River. This new species was named Calyptospora gonzaguensis n. sp. and had ovoid oocysts with a diameter of 19.6 ± 1.4 μm and four peripheral sporocysts, 9.2 ± 0.6 μm long and 3.9 ± 0.2 μm wide, enveloped individually in fine adhesive membrane, composed of an ellipsoid body and posterior extension, with a mean length of 2.2 ± 0.4 μm.

The present study was carried out to investigate the therapeutic effect of Nigella sativa seeds oil emulsion as against Eimeria stiedae experimentally infected rabbits. After isolation of local E. stiedae strain from infected gallbladders, a total of 90 local rabbits (6-8 weeks age) and body weighing (750-1000 gm) were used. They were divided into 6 groups as follow: Group: 1 uninfected and untreated (control group), Group: 2 infected (untreated) with 10,000 sporulated oocysts of E. stiedae, Group: 3 uninfected and given 200mg/kg B.W. N. sativa L. oil emulsion, Group: 4 infected with 10,000 sporulated oocysts of E. steidae. and treated with N. sativa L. oil emulsion of 200 mg/kg B.W on day 16, post infection, Group: 5 uninfected and given 400 mg/kg B.W N. sativa L. oil emulsion, Group: 6 infected with 10,000 sporulated oocysts of E. stiedae. and treated with N. sativa L. oil emulsion of 400 mg/ kg B.W on day 16, post infection. Fecal sample were examined for oocyst count (16 days post infection) at each period of experiment (10, 20 and 30 days) 5 animals for each group were sacrificed, and specimens for liver, were excised for histopathological examination. The E. stiedae infected group showed deleterious pathological changes in infected livers. Both treated doses of N. sativa had significant anticoccidial activities as reflected by reduced fecal oocysts shedding and remarkable improvement of liver tissue histopathology. This improvement include restoration of normal hepatic architecture and increase of the binucleated hepatocytes, disappearance of hemorrhage between the hepatic lobules, formation of foreign body granulomas and reduction in the various stages of the parasites and oocysts in the bile ducts .The result showed that changes more rapid when animals were treated with 400 mg/ kg/ B.W of N. sativa seeds oil emulsion than when treated same emulsion at dose 200 mg/ k.g/ B.W without side effects. From the results obtained in the present study N. sativa seeds oil emulsion was safe without side effects and the dose 400 mg/kg/B.W was more effective against E. stiedae infection than dose 200 mg/kg/B.W which may be recommended for use as adjuvant therapy in clinical practices.

The present study focuses on the anatomopathological alterations provoked by parasitism by Calyptospora sp. in 40 specimens of Aequidens plagiozonatus collected in Pará, Brazil. Examinations of the fresh material by compression of the hepatopancreas and histological sections showed immature forms and oocysts characteristic of the genus Calyptospora, in addition to a large quantity of melanomacrophagic centers spread throughout the organ. No significant inflammation of the hepatic tissue was observed. The melanomacrophagic centers and the compression of the hepatocytes are part of the response of the host to the parasite. This study represents the first record of parasitism by Calyptospora in A. plagiozonatus. Descreveram-se as alterações anatomopatológicas provocadas pelo parasitismo por Calyptospora sp. em 40 espécimes de Aequidens plagiozonatus, provenientes do município de Peixe-boi, Pará, Brasil. Foram encontradas formas imaturas e oocistos característicos do gênero Calyptospora, nos exames frescos por compressão e cortes histológicos, além de um grande número de centros melanomacrofágicos dispersos por todo o órgão. Digna de nota foi a ausência de inflamação significativa no tecido hepático. Centros melanomacrofágicos e compressão dos hepatócitos estão envolvidos na resposta do hospedeiro ao parasito. Este é o primeiro registro de ocorrência de parasitismo por Calyptospora sp. na espécie estudada.

Made available in DSpace on 2014-06-11T19:33:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-02Bitstream added on 2014-06-13T21:06:05Z : No. of bitstreams: 1 freitas_flc_dr_jabo.pdf: 1139081 bytes, checksum: 856bf3c96a6f7eed40da1a35b470f7ae (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) A infecção experimental por Eimeria stiedae em coelhos foi realizada com o objetivo de avaliar os sinais clínicos, alterações hematológicas, metabólicas e anatomopatológicas. Foram utilizados 50 coelhos, raça Nova Zelândia, brancos, com idade entre 40 - 60 dias e de pesos semelhantes. Os animais foram randomizados com relação ao peso e distribuídos em 2 grupos experimentais: grupo infectado, inoculado com 1ml de solução contendo 1x104 oocistos esporulados de E. stiedae; grupo controle, inoculado 1 ml de água destilada. Os animais foram avaliados semanalmente, durante 28 dias, a partir da data de inoculação. Os dados foram avaliados utilizando-se método estatístico não paramétrico pelo teste de Wilcoxon ao nível de 5% de significância. Coelhos infectados com oocistos esporulados de Eimeria stiedae tiveram cirrose hepática que afetou o funcionamento normal do referido órgão repercutindo em produção de proteínas de fase aguda e ocasionando consideráveis alterações metabólicas. The experimental infection by Eimeria stiedae in rabbits was performed to evaluate the clinical signs, hematological, metabolic and pathological changes. Fifty rabbits were used, New Zealand race, white, aged 40 to 60 days and of similar weight. The animals were randomized to the weight and distributed into 2 experimental groups: infected group, inoculated with 1 ml of solution containing 1x104 sporulated oocysts of Eimeria stiedae; control group, inoculated 1 ml of distilled water. The animals were evaluated weekly, for 28 days from the date of inoculation. A statistical was used non-parametric Wilcoxon test method at 5% level of significance. Rabbits infected with sporulated oocysts of Eimeria stiedae had liver cirrhosis that affected the normal functioning of the body resulting in production of acute phase proteins and cause considerable metabolic changes.

Summary The objective of this study was to evaluate some coagulation parameters in hepatic coccidiosis experimentally induced with Eimeria stiedai in rabbits. Fourteen healthy New Zealand rabbits were equally divided into two groups. One group received no treatment, the other group was orally inoculated with 40 000 sporulated oocysts of E. stiedai in a 1 ml inoculum using a catheter. At day 24 after inoculation, blood samples were collected into sodium citrate-containing tubes to evaluate some coagulation parameters. Although statistically not significant, infected rabbits had prolonged prothrombin time and activated partial thromboplastin time compared with rabbits in the control group. A significant reduction (P

To the Editor: Tularemia is a highly pathogenic zoonosis caused by the gram-negative intracellular bacterium Francisella tularensis. F. tularensis causes serious septicemia in animals, especially wild rodents and lagomorphs (rabbits and hares), and potentially fatal, multisystemic disease in humans. The human mortality rate can reach 30% in untreated persons (1). F. tularensis is listed as a category A bioterrorism agent by the Centers for Disease Control and Prevention alongside the causative agents of anthrax, plague, smallpox, botulism, and viral hemorrhagic fevers. Generally, lesions associated with septicemic tularemia include multifocal 1–2-mm, white foci of necrosis in the liver, spleen, lymph nodes, and lungs. Eimeria stiedae is the causative agent of hepatic coccidiosis, a common disease of wild rabbits (2) that can result in severe hepatic injury and death in juveniles and neonates. The gross lesion associated with hepatic coccidiosis is unique and nearly pathognomonic. Because E. stiedae causes proliferation of bile duct epithelial cells, affected livers contain multifocal, well-demarcated, linear, occasionally branching, bosselated, yellow to pearl-gray lesions that reflect the course of the biliary tree. We describe a unique case of tularemia in a rabbit co-infected with E. stiedae. This case was initially misdiagnosed as simple E. stiedae infection on the basis of the classical gross lesions of hepatic coccidiosis, which overshadowed the more subtle tularemia lesions. A juvenile wild rabbit was brought to a local veterinary clinic for postmortem examination. The owner, located in southwestern Missouri near the Arkansas–Kentucky border, raises wild-captured rabbits in a 10-acre, fenced area reserved for the training of hunting dogs. Beginning in the summer of 2009, a gradual rabbit die-off occurred, progressing to almost complete depopulation by May 2010. The liver from the dead rabbit was submitted to the University of Missouri Veterinary Medical Diagnostic Laboratory (Columbia, MO, USA). Gross examination showed the liver contained multifocal to coalescing, linear, yellow to gray nodules consistent with the classical appearance of hepatic coccidiosis. Although no gross evidence of tularemia was observed, the specimen was treated as potentially infected with tularemia because the veterinarian requested F. tularensis testing. Samples were collected and processed for bacteriologic culture, PCR, and histologic evaluation within the confines of a certified biological hood. The liver contained 2 distinct microscopic lesions. The first was severe biliary hyperplasia with numerous intraepithelial coccidia, consistent with hepatic coccidiosis, as was anticipated. The second, more surprising lesion was an acute, multifocal, necrotizing hepatitis (Figure). The differential diagnoses for acute, multifocal, necrotizing heptatitis in a rabbit include tularemia, Tyzzer disease, listeriosis, and salmonellosis. In this instance, F. tularensis was identified by bacterial culture (3) and PCR as previously described (4). No other pathogenic bacteria were isolated on culture. These results were reported to the veterinarian, the owner, and public health officials. All remaining biological specimens were immediately discarded following the University of Missouri’s select agent protocols, and further analysis was halted, preventing further typing of the isolated F. tularensis. Figure Liver from a juvenile wild rabbit with numerous oval Eimeria stiedae oocysts in the convoluted hyperplastic bile ducts (asterisks) and necrotizing hepatitis (arrow) by Francisella tularensis. Hematoxylin and eosin stain; scale bar = 200 ... According to the Centers for Disease Control and Prevention, ≈126 cases of tularemia are reported annually in the United States (5). During 2000–2008, Missouri had the highest number of reported cases (228) followed by Arkansas (149) (5). Two subspecies of F. tularensis are endemic to the United States: the highly virulent F. tularensis subsp. tularensis (type A) and the moderately virulent F. tularensis subsp. holarctica (type B). Transmission of the bacterium occurs primarily through bites from arthropods, including the dog tick (Dermacentor variabilis), the wood tick (D. andersoni), the lone star tick (Amblyomma americanum), and the deer fly (Chrysops spp.). In addition, contact with infected animals, most commonly rabbits, wild rodents, and cats, is another common route of transmission to humans (1,6). Tularemia occurs in various animal species. Lagomorphs, rodents, and sheep are most susceptible; infected animals are frequently found dead or moribund. Carnivores are less susceptible; however, feline tularemia occurs sporadically, and human infections associated with bites and scratches from infected cats have been recognized (7). In addition to arthropod bites, contact with infected dead rabbits or their tissues appears to be the most common source of human infection. A wide variety of case reports have been published describing unique incidences of rabbit–human transmission, including a lawn mower aerosolizing rabbit nests along with their occupants (8), consumption of undercooked rabbit meat (9), and contact with a “lucky” rabbit’s foot (10). The purpose of this report is to alert veterinarians, veterinary laboratory personnel, and public health officials that rabbit tularemia can be easily overlooked on gross examination in animals displaying lesions of hepatic coccidiosis, a common disease of the wild rabbit. Therefore, all rabbits submitted for postmortem examinations should be regarded as potentially infected with tularemia, particularly during seasons when vectors are active.

Thirty young domesticated rabbits (age 2-2.5 mo) of sexes showed clinical signs of anorexia, debilitation, diarrhea, icterus, rough hair coat and pendulous abdomen with hepatomegaly. Fecal samples were collected for demonstrated the presence of oocysts. Postmortem examination revealed the presence of discrete yellowish-white nodules of 1mm to 2 cm size on the surface and throughout the parenchyma containing a thick creamy white fluid. The histopathological changes showed biliary hyperplasia with different developmental stages of Eimeria stiedae in the epithelial cells, cholangitis and peribiliary fibrosis with newly formed bile ductules, severe congestion, and dilation of central veins and sinusoids with disruption hemorrhagic areas. The hepatocytes showed degenerative changes to necrosis with areas of fibrosis and mononuclear cell aggregation, obstructive jaundice and a tendency to form oocyst granuloma. In conclusion hepatic coccidiosis lead to severe pathological changes both in bile ducts and liver parenchyma especially in young animals.

HEPATIC coccidiosis is relatively common in rabbits but only rarely reported in other mammals, including goats, a calf, a dog, and mink (Mahmoud and others 1994, Schafer and others 1995, Oruc 2007). We would like to report two cases of hepatic coccidiosis in 12- to 18-month-old red lechwe (Kobus leche leche) in a mixed-aged herd of 74 animals from a zoological collection. The animals were submitted to Animal Health and Veterinary Laboratories Agency (AHVLA) – Preston for postmortem examination with a brief history of diarrhoea before death. Case 1 had multifocal 1 to 2 mm diameter white spots within the liver, which contained soft white purulent material, and the bile ducts showed multifocal/segmental moderate ectasia containing yellow purulent material and bile. Moderate catarrhal enteritis with a coccidial oocyst count of 62,200 opg was also …

L’examen de foies de 131 lapins (103 jeunes et 28 adultes) achetés directement auprès d’éleveurs locaux et dans des marchés ruraux du Nigeria oriental a montré que la coccidiose hépatique causée par Eimeria stiedai est endémique dans cette région. Quarante et un de ces lapins (37,4 p. 100) étaient infectés. Le rapport entre le foie et le poids corporel, utilisé ici comme indice de la pathologie générale des lapins infectés, a été significativement plus élevé (P < 0,05) chez ces derniers que chez les lapins non-infectés. La coccidiose hépatique a été prévalente chez les lapins dans tous les sites étudiés. D’autres études sur cet aspect de la santé des lapins sont recommandées pour assurer le succès de la production de lapins dans les communautés villageoises du Nigeria oriental.

Coccidial oocysts were seen in the bile from five goats infected with coccidia either naturally or artificially. The oocysts measured on average 21.3 by 18.3 μm and resembled those of Eimeria ninakohlyakimovae . Livers and gall bladders of infected animals showed various degrees of histopathological changes. In the worst case, bile had a thick consistency and contained blood and necrotic debris. Apart from those in the bile, oocysts were seen in liver smears and in the centrilobular vein in two histological sections. Forms resembling meronts and measuring on average 200 by 147 μm were seen in sections of bile duct.

Four groups of 5 40-day-old, Eimeria stiedai -naive, New Zealand rabbits were infected with 0 (Group A), 10 2 (B), 10 3 (C) and 10 4 (D) sporulated oocysts of E. stiedai and observed for 50 days. Serum glutamic pyruvic (GPT) and glutamic oxalacetic (GOT) transaminases, bilirubinemia, lipemia, proteinemia, glycemia, oocyst output, body, carcass and liver weights, and mortality were recorded. Four physiopathological events were identified: (1) a phase of indirect damage to the hepatocytes that takes place during the first 2 weeks of infection and is characterized by increased transaminases; (2) a cholestatic period consequent to the production of oocysts that begins suddenly in the 3rd week, diminishes gradually towards the 7th week, and is characterized by a rise of bilirubinemia and lipemia; (3) a stage of metabolic dysfunction that begins in the 3rd–4th week, intensifies for the next 3 weeks and starts to recover during the 7th week. It is characterized by hypoproteinemia and hypoglycemia; (4) a period of immunodepression characterized by the inability of the heavily infected host to inhibit oocyst production. Apart from the cholestatic phase, the respective pathogenic mechanisms remains to be studied.

The anticoccidial effect of toltrazuril (Bay Vi 9142) against Eimeria flavescens, E. intestinalis, E. magna, E. perforans and E. stiedai was tested in experimentally-infected rabbits. Continuous administration of 10-15 p.p.m. of the drug in the drinking water was highly effective in reducing oocyst output of all five species and in preventing clinical signs and macroscopic lesions. Sporulation of excreted oocysts was not affected. After 5 weeks of medication, no negative influence was noted on zootechnic performance of growing healthy rabbits. Medication of rabbits with 25 p.p.m. only during schizogony or gamogony (2 days of treatment, repeated after 5 days) quickly reduced clinical signs and oocyst output. When administered during late schizogony or gamogony, toltrazuril allowed development of immunity against reinfection with homologous species.

SYNOPSIS. New Zealand White rabbits were fed monensin (Coban® Premix) or amprolium in pelleted feed as a prophylaxis against infection with Eimeria stiedai. Rabbits receiving monensin at 0.005, 0.01, or 0.02% concentrations in the feed did not become infected but ate only small amounts of pellets when the drug concentration was 0.02%. All rabbits given 0.02% amprolium in pelleted feed developed severe infections. Rabbits on “limited” (8 gm pellets per day) diets were susceptible to infection.

Summary Marked distension of the bile ducts was associated with various stages of a protozoan life‐cycle which were identified as schizogony and gametogony. The bile ducts contained oocysts some of which were sporulated and had four sporocysts, each with two sporozoites, thus conforming to the genus Eimeria. This is the first report of a coccidian parasite in the bile duct epithelial cells of birds. It is proposed that this coccidia be named Eimeria grallinida ns.

The efficacy of diclazuril against intestinal and hepatic coccidiosis was studied in artificially infected rabbits. Prophylaxis against intestinal coccidiosis was evaluated using a mixed infection of Eimeria intestinalis, Eimeria magna and Eimeria perforans. Continuous medication in the feed at 1 p.p.m. was 100% effective in reducing oocyst output and faecal scores, and weight gain and feed efficiency were normal. Hepatic coccidiosis induced by Eimeria stiedai was prevented at 0.5 and 1 p.p.m. as shown by negative oocyst counts, normal liver weight, absence of liver lesions, and normal body-weight gain and feed efficiency. Medication at 1 p.p.m. for 7 consecutive days during the prepatent phase of hepatic coccidiosis resulted in large reductions in oocyst counts and lesion scores with a normal liver weight and growth performance. Diclazuril at 1 p.p.m. in the feed prevented both intestinal and hepatic coccidiosis in rabbits and can be advocated for safe mass medication.

Summary The anticoccidial activity of lerbek (clopidol/methylbenzoquate), robenidine and salinomycin against hepatic coccidiosis was examined in rabbits. After experimental infection with 5 × 104 sporulated oocysts of Eimeria stiedae, 200 ppm lerbek and 50 ppm salinomycin prevented the presence of liver lesions completely, while oocyst output was reduced by 99.9%. At lower levels liver lesions were found in 83.3% of the 100 ppm lerbek medicated rabbits and in 66.7% of 25 ppm salinomycin medicated animals, while feed conversion, weight gain and carcass weight at slaughter were not altered. At 66 ppm, robenidine lacked a distinct action against experimental infection with 5 × 104 oocysts of E. stiedae. At lower infective levels (5 × 103 to 2 × 104 oocysts) medication with 66 and 99 ppm robenidine influenced feed consumption and carcass weight favourably, whereas hepatomegaly and oocyst output were reduced considerably. At slaughter less than 3 slight liver lesions were found in 53% of the 99 ppm medicated animals. None of the drugs used had a significant effect on the rate of oocyst sporulation. Zusammenfassung Die Wirksamkeit von Clopidol/Methylbenzoquate, Robenidine und Salinomycin gegen Leberkokzidiose bei Kaninchen Es wurde die kokzidiozide Wirkung von Lerbek (Clopidol/Methylbenzoquate), Robenidine und Salinomycin gegen Leberkokzidiose bei Kaninchen untersucht. Nach experimenteller Infektion mit 5 × 104 sporulierten Eimeria stiedae-Oozysten, wurde mit 200 ppm Lerbek und 50 ppm Salinomycin das Auftreten von Leberlasionen vollstandig verhindert, wahrend die Oozystenausscheidung bis zu 99,9% gesenkt wurde. Nach Gabe niedriger Dosen konnten Leberlasionen bei 83,3% der mit 100 ppm Lerbek und bei 66,7% mit 25 ppm Salinomycin behandelten Tiere festgestellt werden. Die Futterverwertung, die Gewichtszunahme und das Schlachtgewicht wurden nicht beeinflust. Bei einer experimentellen Infektion mit 5 × 104E. stiedae-Oozysten, konnte mit 66 ppm Robenidine keine eindeutige Wirkung erzielt werden. Bei niedrigeren infektiosen Dosen (5 × 103 bis 2 × 104 Oozysten) wurde die Futteraufnahme und das Schlachtgewicht durch eine Behandlung mit 66 und 99 ppm Robenidine gunstig beeinflust, wahrend Hepatomegalie und Oozystenausscheidung erheblich eingeschrankt wurden. Nach Totung wurden bei 53% der mit 99 ppm behandelten Tiere weniger als drei leichte Leberlasionen gefunden. Keines der verwendeten Medikamente besas einen signifikanten Einflus auf die Oozystensporulationsrate. Resume Activite du clopidol/methylbenzoquate, de la robenidine et de la salinomycine contre la coccidiose hepatique du lapins On a examine l'activite anticoccidienne du Lerbek (clopidol/methylbenzoquate), de la robenidine et de la salinomycine contre la coccidiose hepatique du lapins. L'apparition des lesions hepatiques a ete completement inhibee par l'administration de 200 ppm de clopidol/methylbenzoquate ou de 50 ppm de salinomycine, alors que l'excretion d'oocystes a ete diminuee de 99,9% apres une infection experimentale avec 5 × 104 d'oocystes sporules d'Eimeria stiedai. Avec des doses plus faibles, on a constate des lesions hepatiques chez 83,3% des animaux traites avec 100 ppm de Lerbek et chez 66,7% de ceux ayant recu 25 ppm de salinomycine. L'appetence, l'augmentation de poids et le poids a l'abattage n'ont pas ete influences. On n'a pas obtenu d'effet significatif avec 66 ppm de robenidine lors d'une infection experimentale avec 5 × 104 oocystes d'E. stiedai. Un traitement avec 66 et 99 ppm de robenidine a influence favorablement l'appetence et le poids a l'abattage lors de doses infectieuses plus faibles (5 × 103 a 2 × 104 d'oocystes), l'hepatomegalie et la secretion des oocystes etant nettement diminuees. On a trouve moins de trois legeres lesions hepatiques apres l'abattage chez 53% des animaux traites avec 99 ppm. Aucun des medicaments utilises ne possedait une influence significative sur le taux de sporulation des oocystes. Resumen La eficacia de clopidol/metilbenzocuate, robenidine y salinomicina frente a la coccidiosis hepatica en los conejos Se estudio la accion coccidiocida de Lerbek (clopidol/metilbenzocuate), robenidine y salinomicina frente a la coccidiosis hepatica en conejos. Tras la infestacion experimental con 5 × 104 ooquistes esporulados de Eimeria stiedai, se impidio por completo la aparicion de lesiones hepaticas con 200 ppm de clopidol/metilbenzocuate y con 50 ppm de salinomicina, mientras que la expulsion de ooquistes se redujo hasta un 99,9%. Tras la administracion de dosis mas reducidas se pudieron comprobar lesiones hepaticas en el 83,3% de los animales tratados con 100 ppm de Lerbek y en el 66,7% de los mismos medicados con 25 ppm de salinomicina. No hubo influjo alguno sobre la conversion de los alimentos, el incremento ponderal ni el peso de la canal. En una infestacion experimental con 5 × 104 ooquistes E. stiedai no se pudo conseguir ninguna eficacia evidente con 66 ppm de robenidine. Con dosis infestantes mas bajas (5 × 103 hasta 2 × 104 ooquistes) fueron influenciadas favorablemente la ingestion de alimentos y el peso de la canal mediante un tratamiento con 66 y 99 ppm de robenidine, a la vez que se redujeron mucho la hepatomegalia y la expulsion de ooquistes. Tras la muerte se hallaron en el 53% de los animales tratados con 99 ppm menos que tres lesiones hepaticas ligeras. Ninguno de los medicamentos utilizados ejercio un influjo significante sobre la tasa de esporulacion de los ooquistes.

[EN] Hepatic coccidiosis occurred in 56 rabbits belonging to different ages, sexes and breeds during the years from 2002 to 2005. Clinically, the severely affected rabbits showed decreased growth rate, anorexia, debilitation, listlessness, diarrhea, icterus and rough hair coat. Postmortem examinations revealed increased dirty dull straw colored peritoneal fluid. Hepatomegaly, with presence of discrete yellowish-white nodules of 1mm to 1 cm size on the surface and throughout the parenchyma, was seen. Smears from peritoneal fluid showed rafts of mesothelial cells. Impression smears from the liver nodules revealed presence of numerous developmental stages of Eimeria stiedae corresponding with the stage of the liver lesion. These were intermixed with sheats of hepatobiliary cells and inflammatory cells and the changes were reflective of the histological changes like biliary hyperplasia, cholangitis and vacuolar changes occurring in the liver. There was increase in the thickness of basement membrane with the advanced stage of the lesion. The basement membrane was up to 1-2 µm in thickness forming loop like structures over which resided hyperplastic biliary cells containing different stages of the parasite. Some thickened basement membranes were devoid of overlying cells which had desquamated and were present in the ductal lumens suggesting that the basement might have the local defensive role in warding of the coccidial infection. The basement membrane was positive for neutral mucopolysaccharides while as the inflammatory zones and biliary epithelia along with the gametogonic stages of the coccidium reacted positively to the increased acid mucopolysaccharides qualitatively. The results showed that the occurrence of hepatic coccidiosis in female rabbits coincided with the breeding and kindling periods. Direct wet mount smears from bile aid in diagnosis of the disease. Impression smears from the liver nodules might represent the histological changes in the liver. The basement membrane thickening might have a defensive role in warding off the coccidial infection.