Eimeria macusaniensis associated lesions in neonate alpacas dying from enterotoxemia

A Literature Review of Selected Bacterial Diseases in Alpacas and Llamas-Epidemiology, Clinical Signs and Diagnostics

The breeding of South American Camelids (SACs), particularly llamas and alpacas, is becoming increasingly popular in regions that are not their natural habitat, including Europe. These animals are considered to be relatively disease resistant. However, due to their growing popularity, special attention should be given to infections in llamas and alpacas. Knowledge of bacterial infections is very important to veterinarians and breeders. Many of these diseases also have zoonotic potential, so these animals must be considered as sources of potential zoonotic infections. Due to the limited information on many diseases occurring in llamas and alpacas, veterinarians often rely on data collected in other animal species, focusing on cattle, sheep and horses. This work aims to summarise the knowledge of diseases caused by Clostridium spp., Mycobacterium tuberculosis complex, Mycobacterium avium subsp. paratuberculosis, Streptococcus spp., Escherichia coli, Pasteurella multocida, Manheimia haemolytica and Corynebacterium pseudotuberculosis in llamas and alpacas, with particular attention to epidemiology, clinical signs and diagnostics.

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.

A review of coccidiosis in South American camelids

Camelids (llamas, alpacas, vicuñas, guanacos) are important for the economy of South America and Eimeria infections are important as cause of mortality in camelids. Of the five most prevalent species of Eimeria in South American camelids, Eimeria macusaniensis, Eimeria lamae, Eimeria alpacae, Eimeria punoensis, and Eimeria ivitaensis, E. macusaniensis is considered the most pathogenic. There is considerable confusion concerning the endogenous developmental stages of Eimeria spp. in camelids. Many papers on camelid coccidiosis were published in local Peruvian journals, not easily accessible to wider audience. The objective of the present paper is to summarize information on history, validity of Eimeria species, life cycle, pathogenicity, prevalence, epidemiology, diagnosis, and control of coccidiosis in camelids.

Gametogony of Eimeria macusaniensis Guerrero, Hernandez, Bazalar and Alva, 1971 in llama (Lama glama)

Camelids (llama, alpaca, vicunãs, guanacos) are important for the economy of South America and Eimeria infections are an important cause of mortality in camelids. Of the six species of Eimeria in camelids, Eimeria macusaniensis, considered the most pathogenic, is distinctive; its oocysts are the largest among all Eimeria species in animals, its prepatent period is more than 1 month, and its oocysts have been found in mummies from prehistoric times. Although, E. macusaniensis gametogonic stages are found associated with enteritis in naturally infected camelids, the schizogonic stages are unknown and clinical disease has been reported in some camelids with no oocysts in feces. Described herein are morphological details of gametogonic development and oocyst formation of E. macusaniensis in a naturally infected llama (Lama lama), solely infected with this parasite. Microgamonts, macrogamonts and oocysts were located in large (up to 300 µm diameter) parasitophorous vacuoles of enterocytes in the ileum. Schizonts were not found. Review of previous reports suggests that multinucleated microgamonts have been mistaken for schizonts. Gametogonic development described in the present study can serve as a guide for differential diagnosis of Eimeria species in the histological sections of intestines.

Camelidae

New world (NW) camelids, alpaca, llama, vicuña, and guanaco, and old world (OW) camelids, Bactrian and dromedary camels are related and have many of the same anatomical features and disease susceptibilities though they are also very different. Only the free-ranging population of wild Bactrian camel is endangered. Bactrian camels held in zoos are generally of domestic origin. Vicuña are listed as vulnerable. In addition to those camelids held in captivity, there are domesticated populations of camelids (except vicuña and guanaco) maintained throughout the world. Most are fairly hardy animals, but there are some specific disease concerns. Domesticated llamas and alpacas have become hobby pets and thus management and genetic issues are an increasing source of disease. These include obesity, vitamin and mineral deficiencies and intoxications, metabolic derangements, and congenital malformations (particularly in the young). Domesticated animals are also more prone to degenerative arthropathy and dental disease as they age than wild camelids. Ovarian hydrobursitis is an important source of infertility in dromedaries. Important infectious diseases include coccidiosis, bovine viral diarrhea virus, alpaca fever, and meningeal worm of NW camelids, trypanosomiasis and camelpox in OW camels, and foot and mouth disease in Bactrian camels and NW camelids. These and other disease processes are discussed in this chapter.

Prevalence and factors associated with the occurrence of bacterial enteropathogens in suckling piglets in farrow-to-finish herds

The aim of the study was to determine both environmental and infectious factors, influencing occurrence of bacterial enteropathogens in suckling piglets. For this purpose, a cross-sectional study in 70 Polish farrow-to-finish pig herds was performed. In each herd, presence of selected intestinal pathogens (Escherichia coli, Clostridium perfringens and Salmonella species) in faeces of suckling piglets were determined using bacteriological and PCR methods. Using logistic regression models, risk factors for enterotoxigenic E coli with fimbriae F4 (ETEC-F4) and C perfringens type A were established. Prevalence of bacterial enteropathogens in investigated herds was as follows (on herd and sample level): ETEC-F4 30.0 per cent and 9.3 per cent, respectively, C perfringens type A 91.4 per cent and 58.3 per cent, C perfringens type C 1.4 per cent and 0.3 per cent, Salmonella species 2.9 per cent and 0.5 per cent. The occurrence of ETEC-F4 was associated with presence of diarrhoea in piglets and vulval discharge in sows. Vulval discharge in sows, not slatted floor in farrowing pen and lack of coccidiosis prevention were determined as risk factors for C perfringens type A. The results obtained in the study revealed the high prevalence of enteropathogenic bacteria in pig herds and indicate management and organisation of production as factors having the greatest impact on the incidence of bacterial enteropathogens in piglets before weaning.

Characterization of paneth cells in alpacas (Vicugna pacos, Mammalia, Camelidae)

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We determinated Paneth Cells in fetus, offspring and adults alpacas.

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Studies of Paneth cells were done by cytochemistry, immunohistochemistry and lectinhistochemistry techniques.

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We describe Paneth Cell morphometry in fetal, young and adult alpacas.

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We founded Paneth cells in all the small intestinal sections from mid-gestation.

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PC location was similar to that described in other mammals, however they were more columnar than the conventional pyramidal shape.

Paneth cells are secretory epithelial cells of the innate immune system of the intestine of several mammals, including alpacas. Little is known about the latter; thus, in the present study we described the morphology and histochemical characteristics of Paneth cells in healthy fetuses, and young and adult alpacas. For this purpose, samples of duodenum, jejunum and ileum were taken from 6 fetuses at different days of pregnancy (between days 221–330), 66 offsprings (between 0 and 45-days-old) and 5 adult alpacas (>2-years-old). Samples were fixed in 10% buffered formalin and processed for histological and morphometrical analysis using HE and Masson Trichomićs technique. Immunohistochemistry was used to identify Paneth cells using anti-lysozyme antibody. In addition, the lectinhistochemichal binding-pattern of Paneth celĺs granules was evaluated. Lyzozyme was immunohistochemically detected in the granules of Paneth cells from day 283 of pregnancy in all the small intestinal sections of the studied fetuses. In newborn alpacas Paneth cells were initially found in the duodenum, but the following days (days 18–21 after birth) they were also found in the ileum. Their size gradually increased after birth, but then no significant differences were found. In adult alpacas the number was lower than offsprings. We suggest that Paneth cells early differentiate in the small intestine of alpacas, and the increase in their number during the first two weeks of life strongly support their possible involvement in the intestinal defensive functions against the enteric diseases that occur during the lactancy stage.

Prevalence and risk factors associated to Eimeria spp. infection in unweaned alpacas (Vicugna pacos) from Southern Peru

A total of 350 faecal samples from unweaned alpacas over 3 months of age were collected from 23 herds in order to determine the prevalence of Eimeria spp. in Southern Peru and to identify the risk factors associated to Eimeria infection in young alpacas. Samples were examined by a flotation technique and the identification of risk factors was assessed by a logistic regression analysis. Sixty four percent of the examined animals shed Eimeria oocysts; herd prevalence was 96%, with an intra-herd prevalence of 60% (range 5.9-100%). Five different Eimeria species were identified, being E. lamae (91%), E. alpacae (87%) and E. punoensis (78%) the most prevalent; E. macusaniensis (35%) and E. ivitaensis (13%) were less common. Mixed-species infections were more frequent (78%) than single infections (22%). E. lamae was the most common monospecific infection and E. lamae/E. alpacae the most frequent association. The geographical area has a significant effect on Eimeria infection rates (74.9% wet Puna vs 37.4% dry Puna) as well as the breeding system (65.1% traditional vs 63.8% modern). In contrast, the sex of the animals (64.6% males vs 64.0% females) showed no influence on the prevalence of infection by Eimeria. The high prevalence found at both individual and herd level and the common presence of highly pathogenic Eimeria species may lead to important economic losses for alpaca breeders and could require the implementation of suitable control measures.

Llamas and alpacas in Europe: Endoparasites of the digestive tract and their pharmacotherapeutic control

There are distinctive specifications for veterinary medical care of South American camelids (SACs), namely, llamas, alpacas, vicunas and guanacos. Camelids are classified as food-producing animals, but as veterinary medicinal products are often only licensed for domestic food-producing species such as horses, goats, sheep and cattle, treatment of SACs generally requires off-label use of drugs. Endoparasitism is a major health concern in camelids and can result in severe clinical diseases and economic losses. There is still a lack of work on the pharmacokinetics, safety and efficacy for most antiparasitic drugs used in SACs. Even when choosing an appropriate route of administration, several aspects must be considered such as the fact that pour-on formulations are largely ineffective in camelids due to the unique features of llama and alpaca skin and hair that result in extremely low drug bioavailability. This review focuses on the main endoparasites of the digestive tract in llamas and alpacas in Europe and pharmacotherapeutic options based on current knowledge.

Clinical findings and survival in 56 sick neonatal New World camelids

BACKGROUND

Information pertaining to clinical presentation and outcome of neonatal New World camelids (NWC) is limited when compared to calves and foals.

HYPOTHESIS

Values of variables at admission and subsequent treatment would predict survival in sick neonatal NWC.

ANIMALS

Fifty-six client-owned sick neonatal NWC presented over a 10-year period to the Purdue University Veterinary Teaching Hospital.

METHODS

A retrospective study was performed. Inclusion criteria were NWC less than 30 days of age with complete medical records that presented between 2000 and 2010.

RESULTS

The median age at presentation was 1 day (range 1-20). The most common diagnoses were systemic inflammatory response syndrome (50%), congenital defects (41%), ophthalmic lesions (21%), sepsis (16%), and gastrointestinal diseases (16%). Sixty-six percent of NWC survived to discharge. Clinicopathologic findings on admission were variable and not specific for disorders. Factors associated with survival were absence of choanal atresia (P = .001, OR: 55.9 [2.5-1,232]), administration of llama plasma (P = .013, OR: 4.9 [1.4-17.7]), and antimicrobial treatment with trimethoprim-sulfamethoxazole (TMS) (P = .016, OR: 6.5 [1.3-32.2]).

CONCLUSIONS AND CLINICAL IMPORTANCE

The use of antibiotics, particularly TMS, and llama plasma are recommended in sick neonatal NWC. Results from this study could contribute toward defining a NWC-specific sepsis scoring system.

Development of a nested polymerase chain reaction assay for the detection of Eimeria macusaniensis in camelid feces

OBJECTIVE

To test the ability of a nested PCR assay to detect Eimeria macusaniensis at various stages of infection in alpacas.

ANIMALS

4 healthy adult alpacas with no detectable E. macusaniensis.

PROCEDURES

Alpacas were inoculated with 2 × 10(4) sporulated oocysts. Serial fecal samples collected during the next 38 days were tested via sucrose flotation and PCR assay.

RESULTS

Oocyst passage was detected via fecal flotation in all 4 alpacas 31 to 35 days after inoculation. Three had positive results for PCR assays on samples obtained 7 to 14 days after inoculation. One alpaca subsequently was removed from the study because of weight loss and inappetence. Two remaining alpacas had positive PCR reactions 28 and 31 days after inoculation, up to 7 days before oocysts appeared in the feces. All fecal samples with positive results for flotation also had positive results for PCR assay.

CONCLUSIONS AND CLINICAL RELEVANCE

The PCR assay was able to detect early (7 to 14 days) and late (28 to 31 days) prepatent infection. These positive results suggested that the assay could have been detecting DNA unassociated with oocysts or detecting shedding earlier than has been previously recognized. The gap between the early and late detection periods may not be evident in alpacas receiving a larger or continuous inoculum, as might occur with natural infection. Use of a PCR assay for analysis of fecal samples may be valuable for detection of E. macusaniensis during the prepatent period, thus aiding in the identification and control of infected animals.