Occurrence of gastrointestinal parasites in slaughter rabbits

Infection of Egyptian domestic rabbits, Oryctolagus cuniculus, with Cysticercus pisiformis (Cestoda: Taeniidae): morphological, molecular, and histopathological diagnostic tools

Cysticercosis raises the alarm for domestic rabbits since it has a significant impact on their health, productivity, and nutritional value. In this study, several white creamy- colored cysts were detected in the mesentery of the stomach and intestine, as well as embedded in the liver of domestic rabbits collected from Qena Governorate, Egypt. Based on both morphological and molecular assessments, revealed cysts could be identified as Cysticercus pisiformis, the larval stage of Taenia pisiformis. Gross and histopathological investigations of infected organs were documented. To our knowledge, this is the first geographical report on Cysticercus pisiformis in domestic rabbits in Qena Governorate, using current morphological, molecular, and histopathological methodologies that provide critical data for developing diagnostic targets for C. pisiformis.

Potential control of the infective stage of Taenia pisiformis using Bacillus thuringiensis GP526 strain

The GP526 strain of Bacillus thuringiensis has been referred as an in vitro helminthicide on various stages of Dipylidium caninum and Centrocestus formosanus. Our study addresses the in vitro ovicidal activity of GP526 strain spore-crystal complex on Taenia pisiformis eggs, evaluating induced damage microscopically. The eggs exposed to the total extract containing spores and crystals show damage after 24 hours, with loss of integrity on the eggshell, and an ovicidal activity of 33% at 1mg/ml. The destruction of the embryophore was observed after 120 h with a 72% of ovicidal activity at 1 mg/ml. The LC50 was 609.6 μg/ml, dose that causes a 50% of lethality on the hexacanth embryo, altering the oncosphere membrane. The spore-crystal proteins were extracted, and the protein profile was obtained by electrophoresis, finding a major band of 100 kDa suggestive of an S-layer protein, since an S-layer was immunodetected in both, spores and extracted proteins. The protein fraction containing the S-layer protein presents adhesion to the T. pisiformis eggs, and 0.4 mg/ml of the protein induces a lethality of 21.08% at 24 h. The characterization of molecular mechanisms of ovicidal activity will be an important contribution, so the characterization of the proteins that make up the extract of the GP526 strain, would be useful to support the biological potential for control of this cestodiasis and other parasitosis. B. thuringiensis is shown as a potent helminthicide on eggs, with useful potential for biological control of this cestodiasis.

The Incidence of Liver Damage Found during Postmortem Examination at the Slaughterhouse

We monitored liver damage in cattle (cows, heifers, fattening bulls, and calves culled from the herd), pigs (sows, finishing pigs, and piglets culled from the farm), sheep (ewes and lambs), goats (does and kids), rabbits, and poultry (end-of-lay hens, broiler chickens, turkeys, domestic ducks, and domestic geese) in the period from 2010 to 2021. All animals (n = 1,425,710,143) reared on Czech farms and slaughtered at slaughterhouses in the Czech Republic were included in the analysis. We determined the total number of damaged livers for individual categories of animals and also analyzed separately the incidence of damage of acute, chronic, parasitic, and other origin. The overall incidence of liver damage was higher in adult animals compared to fattening animals in all species. In cattle and pigs, the incidence was also higher in young animals culled from the herd compared to fattening animals. When comparing adult animals by species, the incidence of liver damage was highest in cows (46.38%), followed by sows (17.51%), ewes (12.97%), and does (4.26%). When comparing fattening animals by species, the incidence was highest in heifers (14.17%) and fattening bulls (7.97 %), followed by finishing pigs (11.26%), lambs (4.73%), and kids (0.59%). When comparing young culled from the herd by species, it was higher in piglets (32.39%) than in calves (17.6 %), and when poultry and rabbits were compared, the incidence was highest in turkeys (3.38%), followed by ducks (2.20%), geese (1.09%), broiler chickens (0.08%), and rabbits (0.04%). The results indicate that fattening animals have a better liver condition than mature animals and that culled young have a worse liver condition than older fattening animals. Chronic lesions represented the dominant proportion of pathological findings. Parasitic lesions occurred, first and foremost, in animals grazed on meadows with likely parasitic invasion, i.e., in ewes (7.51%), lambs (3.51%), and heifers (1.31%), and in animals in which antiparasitic protection is limited in view of the protection of meat from antiparasitic residues, i.e., finishing pigs (3.68%). Parasitic damage to the liver was rarely detected in rabbits and poultry. The results obtained represent a body of knowledge for measures to improve the health and condition of the liver in food animals.

A chromosome-level genome assembly for the rabbit tapeworm Taenia pisiformis

Taenia pisiformis is one of the most widespread gastrointestinal parasites and its larvae (cysticercosis) causes significant economic loss to rabbit industry. No efficient drug is available for this disease to date. To better understand its genomics, we assembled a 211-Mb high quality genome of T. pisiformis at chromosome level with a scaffold N50 size of 20 Mbp. Totally, 12,097 protein-coding genes was predicted from the genome. Genome-level phylogenetic analysis confirmed the taxonomic affiliations with other tapeworms and revealed that T. pisiformis diverged from its closely related relative T. hydatigena ∼ 14.6 Mya. Comparative genomic analyses revealed that the T. pisiformis genome was characterized by adaptive features of strong positive selection signals from carbohydrate/lipid metabolism and body surface integrity, and of expanded gene families related to metabolism of amino acids and lipids. The high-quality genome of T. pisiformis constitutes a resource for the comparative genomics and for further applications in general parasitology.

Efficacy of Ficus sycomorus (Sycamore Fig) Extract on Intestinal Coccidiosis in Experimentally Infected Rabbits

This study was conducted to investigate the effect of the Ficus sycomorus extract on Eimeria intestinalis in experimentally infected rabbits. For this purpose, forty male 30-day-old rabbits (Blanc de Bouscat) were divided into four groups (n = 10 in each group). Rabbits kept in the first group served as negative control (non-treated-non-infected). Rabbits kept in the second, third, and fourth groups were challenged at 10 weeks old with 3 × 10⁴E. intestinalis sporulated oocysts. The third and fourth groups were treated orally with diclazuril 10% (0.05 mg/kg body weight) and F. sycomorus (100 mg/Kg) for three consecutive days, respectively. The efficacy was assessed based on the growth performance parameters, clinical symptoms, oocyst shedding, histopathological findings, and hematological parameters for 16 days post challenge. The study revealed that rabbits treated with F. sycomorus methanolic extract and diclazuril showed mild clinical symptoms with a significant decrease in oocyst shedding compared with the positive control. Moreover, the diclazuril-treated group showed the highest leukocytic count and the lowest monocytes percentage compared with other groups. Furthermore, the lowest lymphocytes percentage was recorded in the control positive group. Histopathologically, moderate coccidia infestation in the intestinal mucosa and moderate hydropic degeneration of hepatocytes were observed in the diclazuril treated group compared with the negative control. However, mild coccidia infestation in the intestinal mucosa and slight coagulative necrosis of hepatocytes was found in the F. sycomorus treated group. In conclusion, F. sycomorus methanolic extract had promising effects on the live performance, oocyst count, and blood variables, while it possesses adverse consequences on the hepatic tissues. Further studies are required to optimize the dose and extraction method to mitigate its side effects.

Eimeria stiedae causes most of the white-spotted liver lesions in wild European rabbits in Cambridgeshire, United Kingdom

In rabbits, a white-spotted liver can be indicative of one of several disease processes, frequently caused by parasites. To date, the prevalence of white-spotted liver in wild rabbits, Oryctolagus cuniculus, in the United Kingdom is undetermined. We evaluated the prevalence and main parasitic etiologies of this entity in a U.K. population of wild rabbits. Wild rabbits (n = 87) were shot in Cambridgeshire for population control, and cadavers were donated for research. Postmortem examination was undertaken, including gross and histologic hepatic examination. Macroscopic lesions consistent with white-spotted liver were found in 46 of 87 (53%) rabbits examined; most of these lesions were considered to be mild. For 28 of 46 (59%) rabbits with gross hepatic lesions, an etiologic agent was apparent histologically. Eimeria stiedae was detected in 21 of 87 (24%) rabbits, and Calodium hepaticum (syn. Capillaria hepatica) was detected in 7 of 87 (8%). In the subset of rabbits killed in the summer, there was a significant association between white-spotted liver and juvenile age class. There was also an association between white-spotted liver caused by E. stiedae and juvenile age class. When restricting analysis to rabbits with white-spotted liver caused by E. stiedae and submitted in the summer, both juvenile age class and female had significant effects. E. stiedae and C. hepaticum can be transmitted to pet lagomorphs via contaminated vegetation, and to humans in the case of the latter, which demonstrates the importance of monitoring the prevalence of these parasitic diseases in wild rabbits.

Managing Disease Outbreaks in Captive Herds of Exotic Companion Mammals

Management of epizootics of exotic companion mammal herds relies on careful observance of animals, proper management and husbandry, adequate nutrition, and stress reduction. Many diseases occur because of the stress of weaning so anticipating this and maximizing sanitation and ventilation, minimizing overcrowding and concurrent disease, and providing enough fiber for herbivores is prudent. Antimicrobial therapy must be carefully considered in the route of administration and the likely risk of enterotoxemia development. Separation of affected animals, rapid diagnostic testing, and implementation of treatment and supportive care minimizes losses during epizootics. Knowledge of potential zoonotic pathogens is important for veterinarians and staff.

Molecular Confirmation of Massive Taenia pisiformis Cysticercosis in One Rabbit in Poland

The aim of this study was to provide molecular characterization, together with phylogenetic analysis, of Taenia pisiformis cysts isolated from rabbit. On the basis of morphological features and molecular analysis, the cysticerci were identified as T.pisiformis metacestodes. PCR was performed with three different protocols to obtain partial sequences of 12S ribosomal RNA (12S rRNA), NADH dehydrogenase subunit 1 (nad1), and cytochrome oxidase subunit 1 (cox1) of Taenia spp. The products from the PCRs were sequenced. Interpretation of the sequencing results of the obtained amplicons, by comparing them with the GenBank database, proved that the causative agent, in this case, was T. pisiformis. The phylogenetic analysis of the received sequences identified a new haplotype. The received data can be used to supplement the species description. To our knowledge, this is the first molecular confirmation of T. pisiformis metacestodes infection in the rabbit, in Poland.

Deaths Due to Mixed Infections with Passalurus ambiguus, Eimeria spp. and Cyniclomyces guttulatus in an Industrial Rabbit Farm in Greece

Domestic rabbits are commercially farmed for their meat whilst gastrointestinal diseases can hinder their production. Passalurusambiguus and Eimeria spp. are two common rabbit intestinal parasites that can cause diarrhoea, among other symptoms, and in severe cases, death. C. guttulatus is a commensal yeast of the rabbits’ stomach that is considered apathogenic but can worsen symptoms in rabbits suffering from coccidiosis. In the present case report, we describe an outbreak of deaths in three different age groups (A: lactating does, B: 58 days old and C: 80 days old) in an industrial rabbit farm in Greece. Symptoms included depression, diarrhoea, inappetence, weight loss, dehydration and ruffled furs. Using a faecal flotation technique, sick rabbits were found to be moderately to heavily infected with P. ambiguus, Eimeria spp. and C. guttulatus. Treatment with fenbendazole and oregano oil combined with hygiene control measures successfully controlled the infections and resolved clinical symptoms. A faecal flotation method or other reliable diagnostic technique should be used regularly in industrial rabbit farms to screen for gastrointestinal parasitic infections. Early diagnosis and control will help to maintain production levels and, therefore, limit financial losses for the farmer while ensuring animal welfare.

Alternatives to robenidine to control gastrointestinal disorders of weaner rabbits in the field

High mortality rates and oocyst excretion are found in weaner rabbits.

Gastrointestinal disorders have multifactorial origin.

Coccidiostats are commonly used in most rabbitries.

Improve understanding of the use of alternatives to robenidine in the form of natural supplements.

Gastrointestinal disorders due to Eimeria sp. and E. coli overgrowth cause high mortality in weaner rabbits and the interest in alternatives to coccidiostats is high. This study aimed to investigate the superiority of natural feed additives towards robenidine preserving gastrointestinal health in the field. Rabbits were divided into four groups, Control Group (CG) exclusively supplemented with robenidine, Sainfoin Group (SG) was supplemented with a combination of robenidine and sainfoin, and two additional groups were respectively supplemented with Herb-All COCC-X (garlic; conessi tree) (HG: Herbal Group) and by a combination of Herb-All COCC-X and Klinofeed (clinoptilolite) (MG: Mineral Group). Eimeria sp. (98,40%) and E. coli overgrowth (73.60%) could be confirmed as the main causes for losses. High mortality rates (SG: 30.00% - MG: 47.50%), also in the groups receiving robenidine (SG: 30.00%; CG: 45.00%), reinforced the importance of alternatives in the field. The natural additives of groups SG, HG and MG did not have a significant influence on the weight gains and the oocyst counts in the jejunum/ileum and caecum of slaughter rabbits at the end of the trial, compared to group CG. Significantly higher oocyst shedding in SG (p = 1.4E-03) and HG (p = 1.4E-05) during the trial may be explained by a higher surviving rate of diseased rabbits in those groups, fostered by beneficial effects of the additives, which should be investigated further.

Generation and application of a monoclonal antibody against the 18-kDa oncosphere antigen of Taenia pisiformis

Taenia pisiformis is a parasite that causes cysticercosis pisiformis, which has acquired economic relevance because of its effects on animal welfare and production. A useful assay for the detection of T. pisiformis is needed for the prevention of cysticercosis pisiformis and control of the parasite. The 18-kDa oncosphere antigen is expressed in the oncosphere of several cysticerci in species of the genus Taenia, including T. pisiformis. This protein plays an important role in tissue invasion and has extensive applications in diagnosis. In this study, the T. pisiformis 18-kDa oncosphere antigen (TPO18) was expressed in soluble form and successfully purified for use in the production of monoclonal antibodies (MAbs) against TPO18. Twenty hybridomas were obtained using ELISA, and the subcloning process identified three positive hybridoma cell lines, which were designated as 4E8, 5G5, and 7E8. MAb 7E8 exhibited the highest titer and had an IgG2b heavy chain and a kappa light chain. Western blot analysis demonstrated that MAb 7E8 reacted with GST-TPO18. Immunohistochemistry showed that TPO18 was widely distributed in the drape and wall of uteri in adults of T. pisiformis adults and in the fibrous layer of the sucker and cyst cavity of T. pisiformis cysticerci. This research will provide a foundation for the development of diagnostic tools and will contribute to a better understanding of the functions of TPO18.

The Health and Welfare of Rabbits as Indicated by Post-Mortem Findings at the Slaughterhouse

Simple Summary

Veterinary inspection at the slaughterhouse plays an important role in the surveillance system for animal health and welfare. The study focused on the quantification and identification of pathological findings in rabbits slaughtered at the slaughterhouses in the Czech Republic in the period from 2010 to 2019. The ratio of the number of pathological findings to the total number of rabbits slaughtered was 0.0214, i.e., for every hundred rabbits, 2.14 findings were made documenting the impairment of health and/or welfare to an extent leading to pathological changes detected during the post-mortem inspection of the rabbits at the slaughterhouse. The pathological findings that occurred most often were those on the limbs (0.84%), trunk (0.71%), kidneys (0.17%), and liver (0.05%), along with generalized changes (0.37%). The results show that findings on the limbs and trunk were dominated by findings of traumatic origin. Findings in the kidneys and liver were most often of a chronic nature. Findings of abscesses were most frequent among generalized findings.

Abstract

The aim of the study was to assess post-mortem findings according to their localization and the nature of damage and to assess the standard of health and welfare of farmed rabbits on the basis of these findings. A total of 40,206 pathological findings were recorded in 1,876,929 rabbits slaughtered at slaughterhouses in the Czech Republic in the period from 2010 to 2019. Pathological findings on the limbs (0.84%), the trunk (0.71%), the kidneys (0.17%), and the liver (0.05%), along with generalized changes (0.37%), occurred most frequently. Findings of traumatic origin dominated among findings on the limbs and trunk, which indicates the inappropriate housing and handling rabbits on farms and during transport. Findings in the kidneys and liver were most often of a chronic nature having an evident correlation with the diet of intensively fed rabbits, with shortcomings in the diet having an impact on the parenchyma with chronic manifestations in the liver and kidneys. Among the generalized findings, multiple abscesses, which were probably associated with the infection of injuries occurring during fattening, and emaciation resulting from current husbandry practices, leading to insufficient feed intake or the development of disease in some individuals, predominated.

Short communication: prevalence of Eimeria spp. infection in domestic rabbits of Polish farms

<p>The studies were carried out on 14 farms which deals with meat race of rabbits breeding. The basic herds had from 14 to 85 rabbits. The studies were carried  on West Pomerania ( near Chojna) and warmińsko-mazurskie province (near Elbląg). Faecal samples were collected from examined animals and quali-quantitatively analysed to evaluate presence and number of Eimeria oocysts. In addition, isolated Eimeria oocysts were identified at the species level following sporulation. The study was based on two flotation methods:Willis-Schlaaf for qualitative and McMaster for quantitative analysis, which helped to establish the number of oocysts in 1g of feces (OPG). Ten species of coccidian were found in which 9 were intestinal (<em>E. exigua</em>, <em>E. perforans</em>, <em>E. media</em>, <em>E. magna</em>, <em>E. irresidua</em>, <em>E. coecicola</em>, <em>E. flavescens</em>, <em>E. piriformis</em>, <em>E. intestinalis</em>) and one was living in liver (<em>E. stiedai</em>).The dynamics of coccidia infection in the annual cycle showed large fluctuations. The OPG coefficient reached its maximum in mid-May at 21 100 oocyst / g. Exact knowledge of the biology of protozoan <em>Eimeria</em> will contribute to the development of prevention programs that stop the spread of the disease in rabbits.</p>

Preliminary detection of mites and coccidia with their zoonotic potential in meat-farmed rabbits in three districts in Selangor, Malaysia

Mites infestation and gastrointestinal parasites including coccidia are common problems reported in pets, petting farms and farmed practices. Sarcoptes sp. and Cheyletiella sp. could be a potential zoonosis from rabbits to human. Detection of mites and coccidia with their zoonotic potential in meat-farmed rabbits from three (3) commercial farms in Selangor were investigated. Tape impression, fur pluck, skin scraping and ear swab tests were used for mites detection and faecal samples was used for coccidia examination by using McMaster's technique and the identification of Eimeria spp. was further analysed by sporulation technique. The overall prevalence of mites and Eimeria spp. (oocysts) in rabbits were 51.85% ± 0.38 (standard deviation; S.D.) and 76.47% ± 0.42 respectively. Sarcoptes scabiei was the most frequent mite found (25.92% ± 0.44), followed by Cheyletiella parasitovorax and Psoroptes cuniculi. Nine Eimeria spp. were identified and the oocysts of E. perforans shows the highest prevalence (64.71% ± 3.97) followed by E. exigua, E. coecicola, E. magna, E. flavescens, E. irresidua, E. intestinalis, E. media and E. stiedai. There was a significant difference (p = 0.013) where large-scale farm has a higher prevalence of coccidia than small scale farms apparently due to the excessive stocking density as coccidia are easily transmitted among rabbits through ingestion of sporulated oocysts. In conclusion, mites and coccidia are commonly present in the commercial rabbit farms, thus control and preventive measures should be executed to reduce the incidence of parasites. The zoonotic mites Sarcoptes scabiei and Cheyletiella parasitovorax detected in this study could be regarded as a public health concern especially when handling the rabbit.

INTENSITY OF INVASION IN EMERIOSIS OF RABBITS IN DIFFERENT METHODS OF KEEPING

One of the important problems in raising rabbits is eimeriosis, regardless of the method of maintenance. The disease affects animals of all ages, causing weight loss, feed conversion, morbidity and death. The aim. Study of the prevalence and diagnosis of rabbit eimeriosis by different housing technology to improve methods of disease control. Methods. The experiment was conducted during 2017–2019 in farms with different capacities in four regions of Dnipro, Zaporizhia, Kharkiv and Sumy. A total of 20 farms for keeping rabbits of different breeds were surveyed. Results. Studies of rabbit farms on business and private ones found that the most common infestation was with the following species of eimeria: Eimeria perforans, E magna, E. media, E. irresidua, E. piriforms and E. іntestinalis. It is proved that the extensiveness of rabbit infestation when kept in farms in metal cages, under the conditions of sanitary and hygienic regime and timely disinvasion of premises, was in the range of 42–15 % in autumn-winter period, and 19–6 % in spring-summer. According to the survey of homestead farms, rabbits kept in wooden cages on deep litter, the level of invasion in the autumn-winter period was 100–56 % and in the spring-summer – 70–29 %. Conclusions. Keeping rabbits in metal cages in compliance with sanitary and hygienic standards and timely disinvasion reduces the level of extensiveness of the invasion.

The effect of the sex, age, and breed of farmed rabbits and the choice of management system on the extensity and intensity of Eimeria infection

Background and Aim:

The most common causes of loss and diarrhea in rabbit farming are nutritional errors and coccidiosis. The infection can spread rapidly throughout a breeding area, reducing the rabbit population, and causing heavy losses. The aim of the study was to determine the influence of the system of animal management on the extensity and intensity of infection by Eimeria of farmed rabbits, together with the effect of the sex, age, and breed of the rabbits themselves.

Materials and Methods:

The study included 91 rabbits (Flemish Giant, New Zealand White, French Lope, Vienna Blue, California White, and mixed breed) from eight domestic (small-scale) farms from Poland. The prevalence and intensity of coccidial infection were determined by the Willis-Schlaf and McMaster coprological methods. The species were determined based on oocyst morphology: Their shape, color, form index, the presence or absence of micropyle and cap, and the presence or absence of residual, polar, and Stiedé bodies.

Results:

Seven species of Eimeria were isolated from the tested rabbits: Eimeria magna, Eimeria media, Eimeria perforans, Eimeria stiedae, Eimeria coecicola, Eimeria exigua, and Eimeria irresidua. Most infections were found to be of relatively low intensity. No significant differences in the extensity of Eimeria protozoan infection were observed with regard to sex. However, rabbit age had a significant influence on the extensity of infection by E. magna and of Eimerian protozoans combined. The greatest extensity was observed in rabbits aged below 6 months. For all species of Eimeria, greater extensity was observed among rabbits kept in groups than individually. The system of rabbit management also had a significant influence on the intensity of infection. Those kept in groups demonstrated a significantly higher mean intensity of infection of E. magna and all Eimeria species combined than those kept individually.

Conclusion:

Our findings indicate that Eimeria protozoa are a common occurrence on small-scale rabbit farms. As coccidiosis treatment does not always give good results, prevention is very important in the fight against this disease. It is necessary to develop a new preventive paradigm that pays special attention to the factors that promote the spread and development of infection in domestic (small-scale) farms from Poland. For example, it would be recommended to use large, dry, bright rooms with access to the sun, as these are conducive to preventing the occurrence of coccidia infections.

Ectoparasites and Endoparasites of New Zealand White Rabbits from North West of Iran

BACKGROUND

Rabbits contain several parasites that can be harmful to their health as well as human being's health due to the probability of causing parasitic zoonosis. The present research was designed to study ectoparasites and endoparasites of New Zealand White rabbits in North West of Iran and potential risks of parasitic zoonosis for researchers and owners.

METHODS

Totally, 50 rabbits were purchased from rabbit sellers and breeders in suburbs of Urmia and Tabriz between Jul and Dec 2016. The rabbits were assessed for ectoparasites by hair brushing, skin scraping, acetate tape preparation and othic swabs. They were euthanized and inspected for helminths and protozoa infection. Faecal sampling was carried out directly from recti and the oocysts or cysts were isolated using sedimentation and floatation techniques and the sporulated oocyst were identified based on morphological.

RESULTS

The following parasites, with their respective prevalence; Nematoda: Passalurus ambigus 54%, Trichostrongylus retortaeformis 42%, Nematodirus leporis 32%, Cestoda: Cysticercus pisiformis 26%, Protozoa: Eimeria steidae 44%, E. magna 30%, E. media 12% and Arthropoda: Sarcoptes scabiei 18% and Cheyletiella parasitivorax 38%. No significant difference was recorded in infection rate between male and female rabbits.

CONCLUSION

Both domestic and wild rabbits are a potential source of human parasitic zoonosis, and strict hygienic practices are recommended during and after handling rabbits or in case of exposure to their feces.

Gastrointestinal Diseases of Rabbits

Gastrointestinal stasis syndrome is a very common presentation of an ill rabbit to the veterinarian. The causes involved in this syndrome are often multifactorial, and an inappropriate diet puts the rabbit at a greater risk of developing this syndrome. Complications of this disorder can lead to gastrointestinal obstruction, a life-threatening condition that necessitates aggressive medical and in some case surgical therapy. Rabbits may also be presented with signs of diarrhea. However, abnormal cecotrophs must be differentiated from true intestinal diarrhea. The common causes, diagnosis and management of diarrhea including dysbiosis and enteritis are discussed. Other important causes of gastrointestinal disease are infectious disease and liver lobe torsion. Rabbit hemorrhagic disease virus has a new variant that has been identified in mainland Europe, the United Kingdom, and Australia. Subclinical infection of intestinal coccidiosis is a common cause of weight loss in adult rabbits. Liver lobe torsion is a challenging condition to diagnose in rabbits; this chapter discusses the presenting signs, diagnostic techniques, and therapeutic options.

Genetic Diversity of IGHM and IGHE in the Leporids Revealed Different Patterns of Diversity in the Two European Rabbit Subspecies (O. cuniculus algirus and O. c. cuniculus)

Simple Summary

The study of European rabbit immunoglobulin genes has contributed decisively to the current knowledge on antibody structure and diversification. The European rabbit has also been increasingly used as an animal model for the study of many human diseases, such as syphilis, tuberculosis, and AIDS. As such, the study of its immune system genes is of crucial relevance, but the study of rabbit immunoglobulins has focused only on the IgG and IgA antibodies. In this study, we added to the knowledge of the rabbit immune system by investigating the genetic diversity of two antibodies, IgM and IgE, in wild and domestic rabbits as well as other rabbit close species. With the data obtained in this study, we showed a high similarity between the different rabbit close species studied and we pointed out important genetic differences in the wild and domestic rabbits. Our findings are a valuable tool for the management of rabbit wild populations and domestic breeds and may contribute to the identification of immunoglobulins genetic variants with greater efficiency against pathogens.

Abstract

The European rabbit (Oryctolagus cuniculus) has been an important model for immunological studies but the study of its immunoglobulins (Ig) has been restricted to its unique IgA and IgG. Here, we studied the genetic diversity of IgM and IgE in several species of leporids and performed population genetics studies on European rabbit wild populations and domestic breeds. The leporids sequencing showed that these Ig are well conserved (98% sequence similarity among leporids), For IgM the Cµ1 and Cµ4 were the most diverse and most conserved domains, respectively, while for IgE the Cε1 was the most diverse domain and Cε2 and Cε3 the most conserved domains. The differences in the pattern of most conserved and most diverse domain between the Ig isotypes are most likely related to each isotype function. The genetic population data showed contrasting results for IgM and IgE. For both Ig, as expected, a greater diversity was observed in the original species range, the Iberian Peninsula. However, unexpectedly the genetic diversity found for IgE in the domestic animals is higher than that for the French wild populations. These results will increase knowledge of the genetic diversity of leporids and wild and domestic rabbit populations and are important tools for the management of wild populations and rabbitries.

Intestinal and hepatic coccidiosis among rabbits in Yogyakarta, Indonesia

Background and Aim

The attention to rabbit meat production in Indonesia is comparatively less to other farm animals such as cattle and poultry industries. However, future prospect of rabbit to be seriously industrialized seemed quite promising due to rabbit is highly productive and has short reproduction cycle as well as generation interval. One of the diseases infecting many rabbits is coccidiosis caused by protozoan parasite, Eimeria spp. The infectious stage of Eimeria spp. presents ubiquitously in the environment and increases the risk of parasite transmission. Preventive methods such as vaccination are not yet fully developed, while sporadic treatment is not efficiently reduce the cases. In this study, Eimeria spp. infecting rabbits in Yogyakarta Province, Indonesia, were investigated with the aim for precise diagnosis to determine targeted treatment and as a baseline epidemiological data from rabbit in Indonesia.

Materials and Methods

Sample collection was performed randomly for 3 months, from March 2017 to May 2017 and covered areas in Yogyakarta, Indonesia. A total of 750 samples were collected. Eimeria species identification was determined morphologically from the samples after sporulation in 2.5% potassium dichromate byCOCCIMORPH.

Results

Ten species of Eimeria spp. were identified in this study from the positive samples (527/750; 70.3%). Eimeria flavescens was present in 80% of the positive samples, Eimeria coeciola in 78%, Eimeria perforans in 61%, Eimeria exigua in 37%, Eimeria media in 33%, Eimeria stiedae in 31%, Eimeria irresidua in 12%, Eimeria magna in 11%, Eimeria intestinalis in 10%, and Eimeria piriformis in 10%. Coinfection as noted in 80% of the positive samples with 2-6 species in a specimen. E. flavescens and E. coeciola were the most prevalent among all Eimeria spp. (p≤0.0001).

Conclusion

Eimeria spp. is detected in high prevalence among rabbit in Yogyakarta, Indonesia, with commonly occurs in mixed infections. In this paper, we describe Eimeria spp. that are circulating in Indonesia and present it as updated information to farmers and veterinarians. To the best of our knowledge, we provide the first information about rabbit coccidiosis in Indonesia.

Prevalence, Morphological and Molecular Phylogenetic Analyses of the Rabbit Pinworm, Passalurus ambiguus Rudolphi 1819, in the Domestic Rabbits Oryctolagus cuniculus

INTRODUCTION

Passalurus ambiguus, a pinworm nematode parasite, infects domestic and wild rabbits, hares, and rodents worldwide.

MATERIALS AND METHODS

The current parasitological study was performed during January-December 2016, to investigate helminth parasites infecting the domestic rabbit species Oryctolagus cuniculus at the Department of Animal Production, Faculty of Agriculture, Cairo University, Cairo, Egypt.

RESULTS

Of the twenty rabbit specimens examined for gastrointestinal nematodes, 75% were infected with adult oxyurid species, which were morphologically characterized using light and scanning electron microscopy studies. The oxyurid species had a triangular mouth opening surrounded by simple lips with four cephalic papillae and a pair of lateral amphidial pores with three teeth-like structures, an esophagus divided into a cylindrical corpus and globular bulb supported internally with tri-radiate valvular apparatus, and four caudal papillae distributed on the posterior end of males with a single short protruding spicule and ovijector apparatus opening ventrally by the vulva, surrounded by protruded lips in female worms. The species were compared morphometrically with other Passalurus species described previously; light differences were found in different body part sizes. Molecular characterization based on 18 small subunit (SSU) rDNA sequences showed ~ 85% similarity with other Chromadorea species. A preliminary genetic comparison between the 18S rDNA sequences of the isolated parasite and those of other oxyurid species suggested that it belonged to Passalurus ambiguus. The 18S rDNA sequence of the parasite was deposited in GenBank (accession no., MG310151.1).

CONCLUSION

The 18S rDNA gene of P. ambiguus was shown to yield a unique genetic sequence that confirms its taxonomic position within the Oxyuridae family.

DEVELOPMENT OF PREVENTING MEANS FOR RABBITS’ COCCIDIOSIS

The great problem of rabbits breeding today is coccidiosis. An agent of the disease spreads not only through ill animals and is preserved well in the external environment. Oocysts of coccidia live in cells for a long time, so even temporal vacation of an accommodation between placing of rabbits doesn’t prevent infection. It was experimentally proved, that there is a very limited spectrum of means that are coccidiostatics. For preventing and controlling rabbits’ eimeriosis, coccidiostatic means were tested. It is very difficult to annihilate coccidia in vivo and in vitro because of peculiarities of their construction. The aim of the first experiment was to determine the influence of an acidifier Cronocyde L and its components on oocysts of coccidia that allows to determine an optimal composition and concentration of the preparation. At conducting the research, there was used the flotation method of Fulleborn and McMaster one for calculating oocysts. The aim of the second experiment was to determine the influence of the acidifier Cronocyde L standard and Cronocyde L concentrate (1 ml/1l of water) on the intensity of the living mass increment in rabbits. For that there were used clinical, hematological, zootechnical and microscopic methods. Optimal results in the experiment were obtained at using Cronocyde L concentrate and Cronocyde L standard in concentration 0,1 %: maximal growth and health status of rabbits, biochemical indices of blood serum were within the physiological norm. It testifies to the effectiveness of this preparation at eimeriosis of rabbits and to harmlessness for them. The studies, realized under laboratory conditions, prove the effectiveness of the offered means.

Pathomorphological changes in the large intestine of rabbits parasitised by Passalurus ambiguus (Nematoda, Oxyuridae)

Passaluriasis is a common infestation of lagomorphs, which clinically manifests in intense itching around the anus, various disorders of digestion and loss of weight. We performed a study of infested rabbits of the seryi veleten breed, which were kept in individual farms in Poltava Oblast (Ukraine). During the autopsy, in the cavity of the large intestine, there were found small, spindle-like helminths of white colour. Out of 10 rabbits, 846 nematodes were extracted (369 males and 477 females, identified as Passalurus ambiguus (Rudolphi, 1819) Dujardin, 1845. It was determined that the extensity of infestation in female rabbits reached 56.4%, male rabbits – 43.6%. The results of metric parameters of the nematodes are as follows: mean body length of males equaled 4.6 ± 0.4, females – 9.7 ± 1.21 mm, and maximum width – 257.4 ± 17.8 and 546.2 ± 37.1 µm respectively. A common feature of mature nematodes of this species is the presence of a rounded extension (bulbus) at the end of the esophagus. During chronic course of passaluriasis in rabbits, pathomorphological changes developed in the large intestine. The upper epithelium of the large intestine was damaged in some places, certain epithelian cells were found in the lumen of the intestine. The intestinal glands are widened, filled with slimy content of mostly dark blue-violet colour, especially in the upper sections of the glands. In the deep sections of the glands, slime was almost transparent. In deep sections of the glands the slime was almost transparent. In the epithelium cells of the glands, slimy granules were also of basophilic colour. The muscularis mucosae of the mucous membrane, especially between the intestinal glands was swollen, had practically no colour, the collagen fibers were stretched, thinned-out. Edemas were also recorded in the tela submucosa. In some preparations, the muscularis mucosae was notably infiltrated by lymphoid cells and histiocytes. On large extensions, we found some signs of hypersecretion of slime in goblet cells of the intestinal glands as accumulations of granules of slime in the cytoplasm, which had poorly developed colouration. On the side of the muscular and serous membranes, no pathological changes were found. The information presented here indicates the relevance of passaluriasis infestation as an etiological factor of occurrence of chronic catarrhal colitis with lymphohistiocytosis.

Coccidiostatic effects of tannin-rich diets in rabbit production

The potential anti-eimerial effect of tannin containing resources such as sainfoin and carob in rabbits was tested on does at pre-weaning and to growing rabbits in their feed. The trial began at parturition (D0), when 24 does and their litters were assigned into three groups. They were fed either with a control (Group CO), a carob (containing 10% carob pods meal) (Group CP) or a sainfoin diet (containing 34% dehydrated sainfoin pellets) (Group SA). All diets were made isoproteic and isoenergetic and also balanced for crude fibre but differed by their tannin content. Weaning occurred at D37, and growing rabbits remained in the same cage until D51. Then, they were transferred to fattening cages until the end of the trial (D104) and slaughtering. Weight gain of young rabbits among the three groups (mean = 31.2 g/day) did not differ statistically. The mortality rates were 10% (SA), 15% (CP) and 20% (CO), respectively, but the differences were not statistically significant. Post-weaning economical feed conversion ratio (FCR) was reduced between rabbits of group SA compared to CO and CP groups. Faecal oocyst count (FOC) in group SA was 60% lower than in CO and CP groups. Areas under the curve (AUCs) calculated between sampling days and FOC, after transfer to fattening cages, was 62% lower in group SA than in CO and CP groups. The main Eimeria species identified (from D59 to D83) was Eimeria magna (53% of oocysts). AUCs for E. magna did not differ according to diet. In conclusion, the diet containing sainfoin reduced oocyst excretion of Eimeria spp. by 60%, and improved the economical FCR.

Improving agricultural production of domestic rabbits in Serbia by follow-up study of their parasitic infections

A study was made on the prevalence of some parasitic infections appearing in domestic rabbits obtained from individual breeders in Serbia in order to improve the agricultural production of these animals. Aside from economic reasons (meat production and reproduction) rabbits are bred for the research purposes, and races are kept as household pets. For these reasons, among others, it is important to gain knowledge of medical culprits including causes of parasitic diseases that compromise their health, well-being and cause economic losses. This parasitological research was conducted in the period from 2010 to 2015 in 8 epidemiological regions of Serbia, on 433 rabbits as representative samples of different races (154 individuals up to 1 years of age and 279 individuals older than 5). Out of the total number of examined rabbits parasitic infections were established in 82.68% of animals. We detected 3 species of endoparasites (Eimeria spp., Trichostrongylus spp., and Passalurus ambiguus) and 3 species of ectoparasites (Scabies from genera Sarcoptes, Psoroptes and Notoedres). In "kits" (small rabbits) coccidiosis was the most prevalent disease (50.65%), while in older animals trichostrongilidosis was common (39.07%). The most represented scabies infection was with the species Psoroptes cuniculi (12.01%). Aiming at better control on the health of rabbits, there is a growing need for continual monitoring of parasitic infections including appropriate diagnosis, application efficient therapeutic protocols and control measures.

Prevalence of intestinal parasites and risk factor analysis for Eimeria infections in Finnish pet rabbits

No previous published prevalence studies exist on gastrointestinal parasites in Finnish pet rabbits; internationally, similar prevalence figures remain uncommon. This study aimed to estimate the prevalence of gastrointestinal parasites in pet rabbits as well as to determine the possible risk factors for parasitic infections. We analyzed 2-g faecal samples (n=398) from pet rabbits and internet-based questionnaires (n=363) completed by their owners. Owners sent over-night faecal samples to the laboratory, and the samples were quantitatively analyzed within one week using a modified McMaster method. Eimeria oocysts represented the most common parasite found (27%, mean opg 4212). Nematode Passalurus ambiguus eggs were found in 3% of the samples (mean epg 65), while Trichuris leporis eggs and cestode eggs, respectively, were each found in 1 sample (0.25%). We also conducted a risk factor analysis based on the owner questionnaire and the faecal analysis. We limited this to only Eimeria infection due to the low number of positive results for other parasites. In the final multivariable logistic regression model, we identified a young age, multi-rabbit households (with at least three rabbits) and living somewhere other than in a home-like environment as risk factors for Eimeria infection. In similar low-helminth prevalence conditions, we recommend faecal examination and deworming of rabbits according to examination results.

Taenia pisiformis cysticercosis induces decreased prolificacy and increased progesterone levels in rabbits

Reproductive alterations in hosts infected by parasites have been recognized in several phyla, especially in arthropods and mollusks, but it has been less studied in higher vertebrates, particularly in mammals. In the present study, ten eight week-old female New Zealand rabbits (Oryctolagus cuniculus) were either infected with Taenia pisiformis eggs or uninfected, and 7 weeks later they were mated. We found that serum progesterone levels were increased during pregnancy in infected does. At birth, litter size of infected does was reduced by half as compared to the control group, and, at weaning, the number of kits and the weight of litters was lower. Since serum progesterone levels have a key role in the maintenance of pregnancy and implantation, we propose that the observed prolificacy alterations in does infected with T. pisiformis infection were due to changes in the levels of circulating progesterone during pregnancy.

Survey of coccidial infection of rabbits in Sichuan Province, Southwest China

Coccidiosis is a challenging disease of wild and domestic rabbits both, caused by Eimeria and thereby leads enormous economic losses at rabbit farms. The present study carried out to survey the prevalence and intensity of coccidial infection among the rabbits in Sichuan Province, southwest China. A total of 110 faecal samples were collected from 11 farms situated in eight main rabbits rearing administrative regions. Oocysts in faecal samples were purified, sporulated and identified according to morphological features. The overall prevalence of infection was 56.4 % (62/110), with prevalence of 64 % (47/75) for local meat breeds of rabbit and 51.4 % (18/35) for Rex Rabbits (local fur rabbits). Weanling rabbits had the highest prevalence (74 %, 37/50), followed by young rabbits (45 %, 13/29) and the adult rabbits showed the lowest prevalence (42 %, 13/31). Concurrent infection with two to seven Eimeria species was found. In total, 9 species of Eimeria were identified from oocyst-positive samples. E. perforans was the most prevalent specie (42.73 %), followed in order by Eimiera media, E. irresidua, E. magna, and E. intestinalis with prevalences of 35.45, 34.55, 31.82, and 23.64 %, respectively. Results of the present investigation indicated that the prevalence of coccidial infection is high among the rabbit population in southwest China. This study also elucidate about the coccidial infection and emphasis to adopt control strategies in commercial rabbitories.

The complete mitochondrial genome of rabbit pinworm Passalurus ambiguus: genome characterization and phylogenetic analysis

Passalurus ambiguus (Nematda: Oxyuridae) is a common pinworm which parasitizes in the caecum and colon of rabbits. Despite its significance as a pathogen, the epidemiology, genetics, systematics, and biology of this pinworm remain poorly understood. In the present study, we sequenced the complete mitochondrial (mt) genome of P. ambiguus. The circular mt genome is 14,023 bp in size and encodes of 36 genes, including 12 protein-coding, two ribosomal RNA, and 22 transfer RNA genes. The mt gene order of P. ambiguus is the same as that of Wellcomia siamensis, but distinct from that of Enterobius vermicularis. Phylogenetic analyses based on concatenated amino acid sequences of 12 protein-coding genes by Bayesian inference (BI) showed that P. ambiguus was more closely related to W. siamensis than to E. vermicularis. This mt genome provides novel genetic markers for studying the molecular epidemiology, population genetics, systematics of pinworm of animals and humans, and should have implications for the diagnosis, prevention, and control of passaluriasis in rabbits and other animals.