A review of coccidiosis in South American camelids

Pathological findings in South American camelids presented at a farm animal clinic in Northern Germany (2005-2021)

To expand the knowledge about common diseases in llamas and alpacas in Germany, a screening of the cases of South American camelids presented at the Clinic for Swine and Small Ruminants of the University of Veterinary Medicine Hannover, Germany from 2005 to the end of November 2021 was performed. A retrospective evaluation of necropsy reports from this period was conducted. Overall, necropsy reports were evaluated from 187 alpacas, 35 llamas and one vicuña (n = 223). A total of 50.2% of the dissected animals were thin or cachectic. Pathological alterations of the gastrointestinal tract were the most common findings (44.8%). In addition, liver changes were recorded, most frequently in adult animals. In contrast, diseases of the respiratory tract and the nervous system were found more frequently in juvenile animals. This study provides an overview of common pathologies in South American camelids in Germany and thus may help to recognise different disease symptoms at an early stage.

Parasitism-Induced Changes in Microbial Eukaryotes of Peruvian Alpaca Gastrointestinal Tract

Alpacas, important genetic resources in the Andean region of Peru, are vulnerable to diarrhea caused by pathogenic parasites such as Eimeria lamae and Giardia sp., which can be fatal, especially in neonates, due to their physiological immaturity and limited adaptability. The study investigated the diversity and abundance of intestinal fungi and protists in alpacas infected with Eimeria lamae and Giardia sp. compared to healthy alpacas. A total of 19 alpacas, aged between one and two months, were included. They were divided into two groups, one with pathological conditions (nine) and the other healthy (ten). Parasitological analyses for the detection of parasites and subsequent molecular analysis were performed on the collected fecal samples. The results revealed a greater diversity and abundance of protists in infected alpacas in comparison with healthy alpacas, while the fungal composition did not show significant changes. Therefore, parasitic infections affect the protist component of the alpaca gut microbiota. Also, it was observed that Blastocystis was identified in all healthy alpacas, serving as a possible marker of the health of the intestinal microbiota; in addition, Prussia and Pichia are beneficial fungi that help control diseases. This groundbreaking study in neonatal alpacas is the first to explore potential changes in the intestinal microbiota during an infectious state, underscoring the importance of further research to comprehend its effects on alpaca health and immune responses.

A smart economic way to control camel parasites and improve camel production in Egypt

Treatment of the parasites in camels strategically by administration of the specific drugs (Ivomec 1% SC injection, Amprolium hydrochloride orally, Naganol SC injection and Deltamethrin, poure on) at a specially selected time concerning the transmission season of Nematodes, Coccidia, Trypanosoma, Ticks & mite infection respectively causes relief to the animal from the stress of the parasite, minimizes the number of eggs shedding, and improves its general health conditions. However, the present study designed and applied three selected treatment regimes to 300 parasitically infected and controlled camels in Middle Egypt. The first regime was performed by treating animals two times/year during the peak of infection; the first was in April against internal parasites, and in July against external parasites. The second program was conducted by treating animals three times/year; the first was in March against early-arrived internal parasites, the second was in June against external and internal ones, and the third treatment was in August against the rest of the external parasites. Furthermore, the last suggested regime was applied by applying 4 treatments/year: the first was in February against the internal parasites, the second was in May against the early infection by external parasites as well as the remaining internal parasites, and the third was in July against the external parasite. The fourth treatment was in September to eradicate the remaining internal parasite and keep the animal parasite-free during winter. Treatment was applied to the whole flock; however, the movement of treated and control animals was restricted. The study proved a significant decrease in the incidence and level of parasite burden in animals that received 3 and 4 treatments/year, associated with marked improvement in the mean body score, blood parameters, and rate of pregnancy and its related hormones, as well as enhancement in liver and kidney function parameters. The selection of 3 or 4 treatment regimens will be evaluated concerning their economic cost and total income after another year after each protocol's end.

Deciphering Diets and Lifestyles of Prehistoric Humans through Paleoparasitology: A Review

Parasites have affected and coevolved with humans and animals throughout history. Evidence of ancient parasitic infections, particularly, reside in archeological remains originating from different sources dating to various periods of times. The study of ancient parasites preserved in archaeological remains is known as paleoparasitology, and it initially intended to interpret migration, evolution, and dispersion patterns of ancient parasites, along with their hosts. Recently, paleoparasitology has been used to better understand dietary habits and lifestyles of ancient human societies. Paleoparasitology is increasingly being recognized as an interdisciplinary field within paleopathology that integrates areas such as palynology, archaeobotany, and zooarchaeology. Paleoparasitology also incorporates techniques such as microscopy, immunoassays, PCR, targeted sequencing, and more recently, high-throughput sequencing or shotgun metagenomics to understand ancient parasitic infections and thus interpret migration and evolution patterns, as well as dietary habits and lifestyles. The present review covers the original theories developed in the field of paleoparasitology, as well as the biology of some parasites identified in pre-Columbian cultures. Conclusions, as well as assumptions made during the discovery of the parasites in ancient samples, and how their identification may aid in better understanding part of human history, ancient diet, and lifestyles are discussed.

First report about a cerebrospinal nematode infection in an alpaca (Vicugna pacos)

The number of New World camelids in European farms is rising and thus, the need for veterinary care towards these animals arises. However, veterinary care requires sophisticated knowledge on disease and pathogen occurrence within New World camelids. Here, an alpaca cria with neurological signs was admitted to the veterinary clinic. Although the animal was treated with antibiotics, vitamins and dexamethason, it refused to drink milk and the clinical status worsened. After euthanasia, necropsy and histopathological examination were carried out and revealed intracerebral nematode larvae. The morphology of these larvae strongly suggests them to be Baylisascaris procyonis, a parasite of raccoons. The extended history revealed that a fully grown raccoon was living within farm enclosures, suggesting an infection of the alpaca and the development of a cerebrospinal larva migrans. This zoonotic disease is characterized by aberrant larval migration that typically shows extraintestinal migration in dead-end hosts. The aim of this report is to sensitize practical colleagues towards this rare, but occasionally fatal infection in New World camelids while familiarizing diagnostic pathologists with the morphological characteristics of this disease.

Two centrifugal flotation techniques for counting gastrointestinal parasite eggs and oocysts in alpaca faeces

Introduction

The alpaca (Vicugna pacos) is a camelid native to South America, but the species has wide distribution outside its natural habitat and is found in various countries on other continents, Poland being one in Europe. Parasitic infections affect the productivity and health of alpacas. The aim of the study was to estimate the parasite loads in alpacas kept in Poland with the use of two direct centrifugal flotation methods.

Material and Methods

A total of 248 faecal samples from alpacas from 12 provinces in Poland were examined for parasite eggs and oocysts with a modified Willis method (WM), and 59 samples were examined simultaneously with WM and a modified Stoll method (SM).

Results

The WM detected eggs of Trichostrongylidae, and the SM oocysts of Eimeria spp. as the respective most prevalent parasite material. The eggs of Nematodirus sp., Nematodirus battus, Aonchotheca sp., and Trichuris sp. were detected in lower numbers in both methods. Oocysts of E. macusaniensis and eggs of Moniezia sp. were the rarest in WM, the former also being so in SM; eggs of Moniezia were absent in SM. The prevalence of Eimeria spp. was significantly higher as detected by SM than as detected by WM; however, the prevalence of eggs of Nematodirus spp. and trichostrongyles was significantly higher as detected by WM than as detected by SM.

Conclusion

WM is more accurate at detecting heavy gastro-intestinal nematode eggs, including those of trichostrongyles and Nematodirus, whereas SM is more accurate at detecting smaller coccidia from the genus Eimeria.

Eimeria infections in domestic and wild ruminants with reference to control options in domestic ruminants

Eimeria infections are commonly seen in a variety of mammalian hosts. This genus of unicellular sporozoan parasites causes significant disease (coccidiosis) in different livestock species leading to economic losses for agricultural producers. Especially the production of cattle, sheep, and goat is strongly dependent on efficient coccidiosis control. However, many other livestock hosts like, e.g., camelids, bison, rabbits, and guinea pigs may benefit from reduced parasite transmission and targeted control measures as well. Besides livestock, also wildlife and pet animals may be affected by Eimeria infections resulting in clinical or subclinical coccidiosis. Wildlife herd health is crucial to conservation efforts, and Eimeria species are a prevalent pathogen in multiple mammalian wildlife species. This review aims to highlight the epidemiology of mammalian Eimeria infections in both wild and domestic ruminants, including host specificity, transmission, survival of environmental oocysts, occurrence, and risk factors for infection. Understanding general drivers of Eimeria infection may support adequate livestock and wildlife management. Furthermore, control options for livestock with reference to management factors, drug application, and alternative approaches are discussed. The goal of Eimeria control should be to reduce pathogen transmission in different host species and to improve sustainable livestock production. Controlling Eimeria infections in livestock is important considering both their animal welfare impact and their high economic relevance.

Coccidiosis in clinically asymptomatic alpaca (Vicugna pacos) crias from the Peruvian Andes

Parasites of the genus Eimeria are involved in the neonatal diarrhea complex of alpaca (Vicugna pacos) crias, and infection by Eimeria is commonly known as coccidiosis. There are limited reports of these protozoa in clinically asymptomatic crias. In this study, fecal samples from 78 clinically asymptomatic alpaca crias were analyzed to evaluate the prevalence, parasitological load, and diversity of Eimeria species. This study was conducted in the Quenamari community located in the Peruvian Andes (Marangani, Cuzco) at 4500 m above sea level. All fecal samples were examined for parasites using the quantitative McMaster and modified Stoll techniques. Microscopic examination showed the presence of Eimeria oocysts in 68 out of the 78 samples (87.18%). Among the 78 samples we found E. lamae in 67 (85.90%), E. punoensis in 49 (62.82%), E. alpacae in 42 (53.85%), E. macusaniensis in 32 (41.03%), and E. ivitaensis in four (5.13%). Regarding parasitized crias, overall there was a mean parasitological load of 43,920 oocysts per gram of feces (OPG). Eimeria lamae had the highest parasitological load (mean 206,600 OPG). These findings could be due to environmental contamination with oocysts of different Eimeria species. Additional research is needed to determine if this burden of coccidiosis could produce subclinical impacts to the health of alpaca crias.

First report of Eimeria and Entamoeba infection in alpacas (Vicugna pacos) in Shanxi Province, northern China

Intestinal protozoa Eimeria and Entamoeba can infect many animal species including alpacas. However, data on the prevalence and pathogenicity of species of the two genera Eimeria and Entamoeba in alpacas in China is scarce. The current study was carried out to investigate the prevalence of Eimeria and Entamoeba in alpacas in two cities (Taiyuan and Xinzhou) in Shanxi Province, northern China, using PCR-based approaches. Eimeria spp. were only found in Taiyuan city, and the overall prevalence was 1.64%. All samples collected from male alpacas were PCR-negative for Eimeria. Four Eimeria-positive samples were tested positive as Eimeria lamae. The molecular prevalence of Entamoeba in alpacas was 18.03% (66/366), including 16.39% (50/305) in alpacas from Taiyuan city and 26.23% (16/61) from Xinzhou city, respectively. The Entamoeba prevalence in male alpacas (25.00%) was significantly higher than that in female alpacas (15.69%). Entamoeba bovis was the predominant species, and no Entamoeba histolytica infection was detected. Nine unique SSU rRNA gene sequences of Entamoeba were obtained which formed a new cluster. The results showed that sex and location might be the risk factors associated with prevalence of Eimeria spp., and sex might be the risk factor associated with prevalence of Entamoeba spp.. This is the first report of Entamoeba in alpacas worldwide. These findings expand our understanding of the prevalence and genetic diversity of Eimeria and Entamoeba in alpacas.

Presentation, Clinical Pathology Abnormalities, and Identification of Gastrointestinal Parasites in Camels (Camelus bactrianus and Camelus dromedarius) Presenting to Two North American Veterinary Teaching Hospitals. A Retrospective Study: 1980-2020

Old World Camelids (OWC) represent two species (Camelus bactrianus and Camelus dromedarius) with increasing numbers in North America. Gastrointestinal (GI) parasitism is a major cause of clinical disease in camelids and leads to significant economic impacts. Literature reporting on clinical parasitism of camels is localized to India, Africa, and the Middle East, with limited information available on OWCs in North America. Objectives of this study were to report on clinical presentation and diagnostic findings in Camelus bactrianus and Camelus dromedarius with GI parasitism and provide a comparative analysis between geographic regions. Medical records of OWCs presenting to two veterinary teaching hospitals (of the University of Tennessee and University of Wisconsin) were evaluated. Thirty-one camels including 11 Bactrians and six dromedaries (14 species not recorded) were included for the clinical component of this study, reporting on signalment, presenting complaint, and clinical pathology. Anorexia, weight loss, and diarrhea were the most common presenting complaint. Clinical pathology findings included eosinophilia, hypoproteinemia, and hyponatremia. For the second component of this study, a total of 77 fecal parasite examination results were evaluated for parasite identification and regional variation. Trichuris, Capillaria, Strongyloides, Nematodirus, Dictyocaulus, Moniezia, and protozoan parasites (Eimeria, Cryptosporidium, Giardia) were recorded. Strongyle-type eggs predominated, followed by Trichuris and Eimeria spp. There was a statistically significant variation in prevalence of coccidia between the two regions, with fecal examinations from Tennessee more likely to contain Eimeria (P = 0.0193). Clinicians treating camels in North America should recognize anorexia, weight loss, and diarrhea combined with clinical pathologic changes of hypoproteinemia, eosinophilia and hyponatremia as possible indications of GI parasitism. Clinicians should also consider the potential for regional variation to exist for GI parasites of camels in different areas of North America.

Parasitological status of vicuñas (Vicugna vicugna) from southeastern Peru and its relationship with fiber quality

We aim to describe the parasitic population in vicuñas from three Andean communities and its relationship with fiber quality using 115 fecal and 22 fiber samples, classified according to sex, age, body condition score, and management system. Coproparasitologic diagnostic revealed that 84.4% of animals presented at least one type of parasite egg/oocyst. Most frequent parasite egg/oocyst were Strongyle-type eggs (54.8%) and Eimeria punoensis (38.3%). Wild vicuñas had a higher prevalence of Strongyle-type eggs (91.4%) than semi-captive (38.8%) animals, and age was significative to Eimeria infection; crias had the highest frequency (100%) when compared to yearlings (84.2%) and adults (49.4%). Larvae identification revealed a strong influence of domestic animals on vicuña parasite community, presenting the first report of Bunostomum phlebotomum and Gaigeria pachyscelis in vicuñas from southeastern Peru. Females had a significantly finer diameter of fiber (13.05 ± 0.73 μm) than males (14.22 ± 1.22 μm), and infection with Eimeria spp. affected negatively fiber diameter and resistance. Our results provide data for disease surveillance and encourage further parasitological studies in vicuñas.

Exploring Eimeria Genomes to Understand Population Biology: Recent Progress and Future Opportunities

Eimeria, protozoan parasites from the phylum Apicomplexa, can cause the enteric disease coccidiosis in all farmed animals. Coccidiosis is commonly considered to be most significant in poultry; due in part to the vast number of chickens produced in the World each year, their short generation time, and the narrow profit margins associated with their production. Control of Eimeria has long been dominated by routine chemoprophylaxis, but has been supplemented or replaced by live parasite vaccination in a minority of production sectors. However, public and legislative demands for reduced drug use in food production is now driving dramatic change, replacing reliance on relatively indiscriminate anticoccidial drugs with vaccines that are Eimeria species-, and in some examples, strain-specific. Unfortunately, the consequences of deleterious selection on Eimeria population structure and genome evolution incurred by exposure to anticoccidial drugs or vaccines are unclear. Genome sequence assemblies were published in 2014 for all seven Eimeria species that infect chickens, stimulating the first population genetics studies for these economically important parasites. Here, we review current knowledge of eimerian genomes and highlight challenges posed by the discovery of new, genetically cryptic Eimeria operational taxonomic units (OTUs) circulating in chicken populations. As sequencing technologies evolve understanding of eimerian genomes will improve, with notable utility for studies of Eimeria biology, diversity and opportunities for control.

Parasitological survey to address major risk factors threatening alpacas in Andean extensive farms (Arequipa, Peru)

Extensive alpaca farming in the Colca Valley (Arequipa, Peru) is the most important resource for farmers who live in this remote area of the country. Grazing is the major available source of food, whereas forage production and supply are limited. Food availability is low during the dry season predisposing animals to parasitic diseases and reproduction failure. In this study, we looked into gaining an overview about flock health management and nutritional and parasitological status of different age groups in medium-large alpaca farms at the beginning of the dry season. A total of 20 herds were included in the survey and 288 fecal samples were collected and analyzed to determine prevalence and oocysts/eggs output level of the most common gastro-intestinal parasites that affect alpacas. Body condition scoring (BCS), was used to determine the nutritional status of sampled animals, belonging to different physiological classes (i.e. crias, tuis, lactating females, non-lactating females, males). Coccidiosis was the parasitic disease with the highest prevalence and output level. It was the most relevant parasitic disease in all classes and especially in young pre-breeding animals. Higher burdens were found in subjects with lower BCS. More specifically, the farms with higher cria mortality rates showed also a tendency to have higher prevalence values of Eimeria macusaniensis. An improved management of nutritional aspects and parasite control, in particular regarding the weaning phase, is expected to enhance the farming reproductive and productive performances of the alpacas in this region.

Current anthelmintic treatment is not always effective at controlling strongylid infections in German alpaca herds

BACKGROUND

Endoparasites are considered a major health problem of South American camelids as shown in a recent survey among German and Austrian camelid owners. Although prophylactic and therapeutic measures such as application of anthelmintics are commonly used, treatment efficacy is usually not assessed. Owners have expressed significant concerns regarding the effect of antiparasitic therapy, so this study aimed to evaluate the outcome of anthelmintic treatment in German alpaca herds with different drugs.

RESULTS

Overall, 617 samples from 538 clinically healthy alpacas > 1 year-old from 27 farms (n = 11-157 animals/herd) were examined. The most common parasites detected by flotation were Eimeria spp. (75.1%) followed by strongylids (55.0%), Nematodirus spp. (19.3%), cestodes (3.1%) and Trichuris (2.7%). After initial coproscopical examination by flotation and strongylid egg quantification by the McMaster technique, positive animals excreting at least 150 eggs per gram of faeces were included in a faecal egg count reduction test (FECRT) using fenbendazole (n = 71 samples), moxidectin (n = 71) or monepantel (n = 66). Pre-treatment larval cultures (n = 23 positive pooled farm samples) revealed Haemonchus (87% of the farms), Cooperia (43.5%), Trichostrongylus (21.7%), Ostertagia (13.0%), Nematodirus and Oesophagostomum (4.3% each). Fenbendazole treatment reduced egg excretion by 45%, moxidectin by 91% and monepantel by 96%. On the farm level, 13/18 farms that used fenbendazole, 6/6 farms that used moxidectin and 2/5 farms that used monepantel had individual FECR values < 90% (fenbendazole) or < 95% (moxidectin, monepantel). Haemonchus and Cooperia were overrepresented on the farms with reduced treatment efficacy.

CONCLUSIONS

Gastrointestinal strongylids are common in German alpacas and fenbendazole in particular was not sufficiently effective to reduce strongylid egg excretion. Although the FECRT could not unambiguously determine anthelmintic resistance in the present study, the finding that small ruminant strongylids, especially Haemonchus, are common in alpacas indicates that determination of effective anthelmintic doses, monitoring of efficacy and adapted (selective) treatment regimens must be implemented as part of sustainable deworming practices in this species in accordance with recommendations for ruminants.

Endoparasites of Domesticated Animals That Originated in the Neo-Tropics (New World Tropics)

This review serves to summarize parasites found in Domesticated animals which were found in the Neo-Tropics. Indigenous domesticated Neo-tropical animals include South American camelids, (Lama gunacoa, Lama glama, Lama pacos, Vicuna vicuna), guinea pigs (Cavia porcellus), chinchillas (Chinchilla lanigera), turkeys (Meleagris gallopavo) and ducks (Cairina moschata, Anas platyrhynchos, Dendrocyga autumnalis). These animals were chosen due to their origin of existence (Neo-tropics) and over time these animals became domesticated and were distributed throughout the world. Over eighty (80) references were collected for this review and the papers spanned over eighty (80) years from 1934 to 2018. The gastrointestinal parasites reported for each animal were tabulated and their effects in the animal noted. Parasites reported in domesticated Neo-tropical animals had little to no effect on wild and free ranging animals with a few cases of illness and decreased productivity. The majority of articles viewed these animals as reservoir host which can infect humans and other domesticated livestock. It must also be noted that research done in the past did not focus on the effect these parasites had on these animals but only observed their potential as reservoirs for parasitic diseases.

Gametogony of Eimeria cameli in the small intestine of one-humped camel (Camelus dromedarius)

Domesticated Old World camels (Camelus dromedarius and Camelus bactrianus) are important for the economy of several countries in Asia, Africa, and the Arabian Peninsula, and coccidiosis is an important disease in camels. There is confusion concerning the species of coccidian parasites in camels and their life cycles. Although five species of Eimeria (E. cameli, E. rajasthani, E. dromedarii, E. bactriani, and E. pellerdyi) were named from camels, E. cameli is considered the most pathogenic. Here, development of gametogonic stages and oocysts of E. cameli are described in the lamina propria of the small intestines of naturally infected camels. Only sexual stages have been confirmed.

A review of coccidiosis in Old World camels

Domesticated Old World camels (Camelus dromedarius and C. bactrianus) are important for the economy of several countries in Asia, Africa, and the Arabian Peninsula, and coccidiosis is important as a cause of mortality in juvenile camels. There is confusion concerning the species of coccidian parasites in camels and their life cycles. The objective of the present paper is to review biology of the Eimeria and Cystoisospora species in camels. The following conclusions were drawn. Although five species of Eimeria; E. cameli, E. rajasthani, E. dromedarii, E. bactriani, and E. pellerdyi were named from camels, only E. cameli, E. rajasthani, E. dromedarii have been consistently found in numerous surveys and they are morphologically distinct. We consider E. pellerdyi and E. bacterini as species enquirende/ not valid. E. cameli oocysts are distinctive, dark brown and up to 108 μm long. Its gametogonic stages and oocysts are present in the lamina propria of small intestines; only sexual stages have been confirmed. The remaining species of Eimeria (E. rajasthani and E. dromedarii) in camels are <40 μm long and their endogenous stages are unknown. There is one valid species of Cystoisospora, C. orlovi in camels and is associated with severe disease in young camels, both pastoral and stall fed camels. Camels as young as nine days old can develop severe diarrhea and can die before oocysts are detected in feces. Lesions and endogenous stages are confined to the large intestine. The main lesion is hemorrhagic, diphtheroid to hemorrhagic colitis-associated with sexual stages; asexual stages are unknown. Oocysts are rarely excreted by adult camels, and in low numbers. Therefore, infection in very young camels remains unexplained.