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At the beginning of 2000, a population of 1622 South American camelids in 257 herds was living in Switzerland. The origin of the animals, their age, the management systems, their feeding habits, their use as well as the observed medical conditions and the indications for treatment were assessed with a questionnaire. Results of this study show that 60% of the South American camelid population in Switzerland consisted of llamas (999 animals) and 40% of alpacas (623), and that females younger than 4 years of age made up the majority of the animals. South American camelids were predominantly kept for hobby, breeding or trekking. The most frequent health problems were related to the digestive tract, the skin, the eyes and the metabolism. Veterinarians were consulted for deworming, vaccinations, castrations or obstetric interventions. The parasitological examination of 204 fecal samples showed that llamas and alpacas were infested with the same endoparasites as ruminants (i.e. nematodes, trematodes and protozoas).

The efficacy of eprinomectin versus ivermectin (Study 1: a single-centre, randomised, treatment-controlled, blinded field trial), and the field efficacy of eprinomectin (Study 2: a single-centre, open, un-controlled field trial) for the treatment of chorioptic infestation in naturally infested alpacas were assessed in two studies. Thirty alpacas, all positive for Chorioptes sp. mite, were randomly allocated to two treatment groups in Study 1. Group A received a single topical administration of a 0.5% formulation of eprinomectin at the dose rate of 500mug/kg. Group B received three subcutaneous administrations at 14 days interval of a 1% formulation of ivermectin at the dose rate of 400mug/kg. Response to treatment was assessed by periodic mite count, and skin lesions scored. In Study 2, one group of 19 alpacas received four administrations at weekly interval of topical eprinomectin at the dose rate of 500mug/kg, and response to treatment was monitored by mite counts. No localised or systemic side effects were observed in either trial. There was a statistically significant decrease in mite counts on day 7 (P<0.001) within treatment Groups A and B of Study 1, but mite counts increased again on day 14 and remained high for the duration of the trial in both treatment groups. On day 14 of Study 2, there was a statistically significant reduction in mite counts (P<0.008) and the mite counts remained very low throughout the remainder of the study. The eprinomectin protocol employed in Study 2, consisting of four weekly topical administrations at the dose rate of 500mug/kg of body weight, proved highly effective at reducing the Chorioptes mite burden in alpacas.

The present study was designed to investigate Toxoplasma gondii infection in adult llamas (Lama glama) and vicunas (Vicugna vicugna) in the Peruvian Andean region, for which to date no information has been available. Serum samples from 43 llamas (L. glama) and 200 vicunas were tested by IFAT detecting titres of 1:50 or higher in 55.8% (33.9-70.9%) and 5.5% (2.8-9.6%), respectively. IFAT titres ranged from 1:50 to 1:6400. In order to avoid cross reactions with closely related coccidian parasites and to confirm the existence of T. gondii specific antibodies, IFAT positive sera from both ruminant species were also analysed by western blot. T. gondii specific antigens were recognised by IFAT positive sera, although different IFAT cut-off points could be selected for llamas (1:200) and vicunas (1:50) meaning seroprevalence of 44.2% (29.1-60.1%) and 5.5% (2.8-9.6%), respectively. Based on the frequency and intensity of tachyzoite antigen recognition, at least three immunodominant antigens with apparent molecular weights of 22-24, 30, and 38-40 kDa were detected, together with other minor protein fractions located in the 18-73 kDa range. This study documents for the first time the presence of T. gondii infection and reports the target T. gondii antigens in adult llamas and vicunas in Peru.

Sera of an experimentally Neospora caninum infected llama and a non-infected control llama were used to establish an immunoblot, an ELISA and an IFAT to detect antibodies against N. caninum tachyzoites. Subsequently, serum samples collected from a total of 871 South American Camelids (SAC: Lama glama, Lama pacos, Lama vicugna) of two farms in Peru and from 32 SAC of a farm in central Germany were examined for antibodies against N. caninum and Toxoplasma gondii. Based on the recognition of specific bands in the immunoblot, sera of SAC from Peru were differentiated into N. caninum-positive (n = 18) and T. gondii-positive (n = 30) samples and into samples negative or inconclusive for both parasites. Using the immunoblot results as the reference, a modified version of the p38-ELISA and the IFAT were evaluated for detecting N. caninum antibodies in SAC sera. Applying a cut-off as determined by two graph-receiver operating characteristic analysis both, the ELISA and the IFAT, exhibited a sensitivity and specificity of about 95% in the SAC sera from Peru. Serological testing confirmed that SAC may become infected with N. caninum under field conditions in Peru. In addition to alpacas and llamas also 114 wild living vicunas had been examined for antibodies against N. caninum. However, only the alpacas and llamas but no vicunas were found N. caninum-positive. In contrast, T. gondii-seropositive animals were detected in all three SAC species. The lack of N. caninum-seropositive vicunas indicates that in the study area in Peru wild canids might not serve as definitive hosts of N. caninum while for T. gondii a life cycle including wild felids is likely. On the German farm no N. caninum- but only T. gondii-seropositive SAC (n = 14) were detected. The seroprevalence of T. gondii infection was significantly higher in adult SAC (alpacas in Peru, llamas in Germany) than in crias (i.e. < 12 months old foals) indicating that the predominant route of infection is post natal. Since the present study was restricted to a few farms, the seroprevalences determined are not representative. However, our results confirm natural infections with N. caninum and T. gondii in SAC. Whether these infections are linked to any disease, e.g. reproductive losses, has to be clarified in further studies.

Neospora caninum is a cyst-forming coccidian that mainly affects bovines, although Neospora infection has also been described in other domestic and wild ruminant species. Serum samples from 78 alpacas (Vicugna pacos) and 73 llamas (Lama glama) at a unique dilution of 1:50 tested by indirect fluorescent antibody test (IFAT) were further analyzed serologically by IFAT and Western blot in both ruminant species to avoid cross-reactions with closely related coccidian parasites and to confirm the existence of N. caninum-specific antibodies. IFAT titers ranging between 1:50 and 1:800 were found. When using Western blot, N. caninum tachyzoite-specific immunodominant antigens with apparent molecular weights of 17-18, 34-35, 37, and 60-62 kDa were also recognized, although some sera with 1:50 IFAT titers proved not to have N. caninum-specific antibodies. As expected, higher IFAT titers were associated with higher anti-N. caninum reactivity in Western blot. This report documents for the first time the presence of N. caninum infection in adult alpacas and llamas from Peru.

Salmonella typhimurium was isolated from the feces of an alpaca suffering anorexia and weight loss. Multifocal necrotizing and suppurative hepatitis consistent with bacterial infection was found in the liver biopsies. Enteric salmonellosis may be associated with milder physical and clinicopathological changes in camelids than in other large animal species.

Objective: To identify potential pathogens in feces from llama and alpaca crias with diarrhea., Design: Prospective observational study., Animals: 45 unweaned crias with diarrhea., Procedure: Fecal samples were evaluated for Eimeria spp, Giardia spp, Cryptosporidium spp, enteric viruses, and Salmonella spp. A questionnaire yielded information concerning herd management and presence of other affected camelids., Results: 28 crias were < or = 31 days old, 11 were 32 to 62 days old, and 6 were 63 to 210 days old. Potential pathogens were isolated from feces from 32 of the 45 crias. A total of 39 potential pathogens were obtained, including coronavirus (n = 19 crias; 42%), Giardia spp (8; 18%), Eimeria spp (6; 13%), Cryptosporidium spp (4; 9%), rotavirus (1; 2%), and nematode ova (1; 2%). Salmonella spp were not isolated. Most crias from which potential pathogens were isolated were identified during outbreaks of diarrhea involving other camelids, although only coronavirus was isolated from crias identified during outbreaks involving adult camelids. Coronavirus was detected throughout the year, whereas protozoa were most commonly isolated during the fall and winter., Conclusions and Clinical Relevance: Results suggest that a variety of potential pathogens may be isolated from young crias with diarrhea. Many crias shed coronavirus, which may also have been affecting older camelids. Protozoa were isolated most often during wetter months, suggesting that crias born during these months may have greater exposure to protozoal pathogens.

In the winter of 2000, a greater than 80% reduction in the guanaco population located in Cabo Dos Bahi;as Wildlife Reserve, Chubut, Argentina, was evident due to massive mortality attributed to starvation. Twelve guanacos were necropsied and samples were analyzed at the Parasitology Laboratory of Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral. Fecal analysis revealed developmental stages of Nematodirus sp., Marshallagia sp., Trichuris sp. and Eimeria spp. Histopathological analysis showed the presence of Sarcocystis sp. in muscle and fascia cysts. Other parasites recovered included Dictyocaulus filaria, Trichuris tenuis and Moniezia expansa. Of these, D. filaria and M. expansa possibly reflect interactions with domestic sheep. This is the first time that T. tenuis has been reported in guanacos.

The excavations of Chiribaya culture sites in the Osmore drainage of southern Peru focused on the recovery of information about prehistoric disease, including parasitism. The archaeologists excavated human, dog, guinea pig, and llama mummies. These mummies were analyzed for internal and external parasites. The results of the analysis and reconstruction of prehistoric life from the excavations allows us to interpret the pathoecology of the Chiribaya culture.

An adult alpaca (Lama pacos) had a locally extensive area of hepatic atrophy involving the right lobe. Grossly, the atrophic lobe was light tan and firm and contained small, raised, white to yellow, partially mineralized circular nodules predominantly at the periphery of the atrophic tissue. Microscopically, viable hepatocytes were not present in the atrophic area, and the tissue consisted of diffuse biliary epithelial proliferation without any evidence of nuclear or cellular atypia or the presence of mitotic figures. The circular mineralized nodules consisted of granulomatous inflammation with intralesional parasitic ova surrounded by fibrous connective tissue. Morphologically, the ova were compatible with those of Fasciola hepatica. The severe biliary hyperplasia was unusual, and it was not clear whether it was caused by an aberrant host response to the parasitic infection or whether it was an unrelated event.

Circulating antibody against Fasciola hepatica antigens was determined by enzyme-linked immunosorbent assay (ELISA) and immunoelectrophoresis in alpacas naturally exposed to F. hepatica. Serological assay parameters were established by using sera from eight infected animals and seven controls with no record of this parasitic infection. Excretory--secretory (ES-) products, Fas1- and Fas2-ELISA were used to survey 307 alpacas from a F. hepatica endemic area in the Peruvian Andes. Seroprevalence of F. hepatica infection varied from 56.7, 64.8 and 66.8% measured by Fas1-, Fas2- and ES-ELISA, respectively. The sensitivity for ES-ELISA was 95%, corresponding Fas1- and Fas2-ELISA sensitivity values were 90 and 95%. In this population, 7% of animals were positive for F. hepatica eggs in faeces, other parasites detected were Trichuris sp. (40%), Nematodirus sp. (34.6%), Lamanema sp. (12.8%) and Eimeria sp. (11.8%). The results show that F. hepatica infected animals elicit circulating antibodies against ES, Fas1 and Fas2. Fas2-ELISA may be proposed as a sensitive assay for the immunodiagnosis of fasciolosis in alpacas.

Objective: To evaluate fecal shedding of Giardia duodenalis, Cryptosporidium parvum, Salmonella organisms, and Escherichia coli O157:H7 from llamas in California with respect to host factors and management practices., Animals: 354 llamas from 33 facilities., Procedure: Fecal specimens were collected and examined for G. duodenalis and C. parvum by means of immunofluorescent microscopy. Salmonella organisms were cultured by placing feces into selenite enrichment broth followed by selective media. Escherichia coli O157:H7 was cultured by use of modified tryptocase soy broth followed by sorbitol MacConkey agar, with suspect colonies confirmed by means of immunofluorescent microscopy., Results: 12 of 354 fecal specimens (3.4%) had G. duodenalis cysts. Younger llamas (crias) were more likely to be shedding cysts, compared with older llamas. Farm-level factors that increased the risk of shedding were large numbers of yearlings on the property (> 10), smaller pen sizes, large numbers of crias born during the previous year (> 10), and large pen or pasture populations (> 20). None of the 354 fecal specimens had C. parvum oocysts. Seventy-six (from 7 facilities) and 192 (from 22 facilities) llamas were tested for Salmonella organisms and E. coli O157:H7, respectively. All fecal specimens had negative results for these bacteria., Conclusions and Clinical Relevance: Shedding of G. duodenalis was primarily limited to crias 1 to 4 months old. Llamas from properties with large numbers of crias born in the previous year, resulting in large numbers of yearlings in the current year, were at greater risk of infection. In addition, housing llamas in smaller pens or pastures and managing llamas and crias in large groups also increased the risk of G. duodenalis shedding.

Two llamas (Lama glama) were infested with approximately 20,000 Boophilus microplus larvae each and maintained under controlled conditions to collect the detached adult ticks. A total of 72 engorged and semi-engorged females were recovered with a mean weight of 163.0 +/- 70.6 mg. Sixty-three (87.5%) of these ticks oviposited and 60 (95.2%) of the egg masses produced larvae. Six of the heaviest females laid 18,838 eggs from which 16,545 (87.8%) hatched. These results show that llamas are able to maintain a population of B. microplus under experimental conditions. Further studies are required to determine the role of llamas as alternative hosts for B. microplus under field conditions.

The monospecific Lamanema historically has been assigned to the Nematodirinae within the Molineidae. Inconsistencies in morphological characters, within a phylogenetic context for Nematodirinae, led to a re-evaluation of the putative relationships and taxonomic placement of Lamanema. Among 7 putative synapomorphies for Nematodirinae, Lamanema possesses only 1, large eggs. Large eggs, sporadically present in phylogenetically disparate taxa of trichostrongyles, are equivocal with respect to placement of Lamanema; it is considered that possession of this single homoplasious character alone is insufficient justification to retain the genus in Nematodirinae. Affinities with the Trichostrongylidae (Cooperiinae or Haemonchinae) have also been proposed; however, Lamanema possess neither of 2 synapomorphies that diagnose monophyly of the family. Lamanema is retained in the Molineidae and transferred to the Molineinae as it possesses all characters of the family as currently defined. The origin of Lamanema represents a secondary colonization of ruminants by molineids and provides no context for elucidating the history of the Nematodirinae and Nematodirus.

A survey of whipworms was conducted in llamas and vicuñas in northwestern Argentina. Fecal examinations of a group of 14 llamas (April 1995-March 1996) and 69 vicuñas (November 1996) indicated a high prevalence (usually >50%) of Trichuris sp. in these hosts. Prevalence was highest during July-November 1995 that also coincided with the highest mean fecal egg count. During postmortem examinations of 1 llama and 1 vicuña, specimens of Trichuris tenuis were recovered from the cecum/large intestine of each camelid. This is the first report of T. tenuis in South America, and the first report in the vicuña. It is suggested that T. tenuis is the typical whipworm of aboriginal camelids.

Disseminated eosinophilic myositis was diagnosed in an alpaca that had been imported to the USA from Peru 5 years earlier. The myositis was associated with macroscopically visible large sarcocysts that were characterized histologically by septate compartments containing bradyzoites, and ultrastructurally by cyst walls composed of anastomosing villous protrusions. Two hours before death, the alpaca aborted an 8-month-gestation fetus, but no lesions were found in the uterus, placenta or fetus. Additional macroscopical findings included haemoabdomen and myofibre haemorrhage, degeneration and necrosis. It is believed that this is the first described case of clinical disease associated with a Sarcocystis sp. (probably S. aucheniae) in camelids., (Copyright 1999 Harcourt Publishers Ltd.)

In Llamas and Alpacas infestation with Fasciola hepatica or Dicrocoelium dendriticum can cause liver damage, sometimes even with lethal outcome. Once infected South American Camelids (SACs) react more sensitively to these parasites than other domestic ruminants. We report here on the pathology, parasitology, clinics and therapy of this disease. Concerning Dicrocoelium dendriticum we describe own clinical results and therapeutic outcome in addition to the pathological investigation. According to anatomic corrosion casts, the bile ducts of SACs show more similarity with the equine bile system than with the bile system of domestic ruminants.

To compare the prevalence of Eimeria macusaniensis among midwestern llamas (Lama glama), alpacas (Lama pacos), and guanacos (Lama guanicoe), feces were obtained from Lama spp. in 10 states between October 1989 and February 1996. Feces were examined by centrifugal flotation in sugar solution (specific gravity--1.28-1.30), and oocysts were quantified by a modified McMaster method. Data were compared by host species and age classifications. Typical oocysts occurred in samples from 28% of 76 herds and 10.4% of 443 animals including 12% of 301 llamas, 7% of 115 alpacas, and 7.4% of 27 guanacos. Prevalence was significantly greater (P = 0.009) in animals < 1 yr of age in comparison to older animals for llams (22.1 v.s. 8.5%) and for all Lama spp. combined (17.1 vs. 8.4%). Fecal oocyst abundance was significantly greater (P = 0.001) in llamas < 1 yr of age in comparison to older llamas (30 vs. 16 oocysts per g of feces). Fecal oocyst intensities did not differ significantly. Prevalence in both age groups of midwestern llamas was greater than previously reported for llamas in the western United States. Prevalence in midwestern alpacas < 1 yr of age was lower than reported for alpacas of similar age in South America, but oocyst intensities were similar. These results indicate that infection with E. macusaniensis is more common in Lama spp. in North America than previously recognized.

Two pregnant llamas (Lama glama) infected with Toxoplasma gondii and their offspring were evaluated clinically and serologically. Llama 1 was inoculated orally with 1,000 infective occysts of the P89 strain of T. gondii at 82 days of gestation (DOG). Llama 2 became naturally infected with T. gondii between 26 and 119 DOG. Both llamas remained clinically normal and delivered healthy offspring. Sera collected from both llamas during pregnancy and from their offspring before and after colostral ingestion were evaluated for antibodies to T. gondii by the modified agglutination test (MAT), latex agglutination test (LAT), indirect hemagglutination test (IHAT), and the Sabin-Feldman dye test (DT). In llama 1, MAT antibody titers were < 1:20, 1:320, 1:1,280, 1:640, and 1:80 at 82, 97, 109, 132, and 152 DOG, respectively. The MAT titers in naturally infected llama 2 were < 1:32, 1:320-1:640, and 1:1,280 at 26, 119-200, and 346 DOG, respectively. In both llamas, antibody titers in the DT were of similar magnitude as the MAT, but titers in the LAT and IHAT were inconsistent. Antibodies to T. gondii were not detected in precolostral sera obtained from offspring of both llamas suggesting there was no fetal T. gondii infection.

The hematophagous sucking louse Microthoracius mazzai Werneck, 1932, is redescribed and identified as a parasite of alpacas, Lama pacos L. Specimens were collected on animals 10-14 mo old, located on a large community farm at 4,600 m above sea level in the Peruvian Andes. In total, 26 scanning electron microscope (SEM) figures are included that highlight salient and differential characteristics, especially the unique elongated spindle-shaped head, which is almost as long as its abdomen. Alpacas, 1 of the 4 species of South American camelids, are important for their production of high-quality wool in the Andes Mountain range countries, especially Peru and Bolivia; to a lesser degree Chile; and more recently Argentina, where breeding and disease control programs are receiving increased technical support. Information is given on the prevalence of lice infestations in the flock, clinical signs, and economic losses. We report the efficacy of moxidectin (SC, 200 mcg/kg, b.w.) in a repeated treatment program of 7-10 d, which is currently used for mange control in these ruminants.

A 9-year-old llama examined because of hind limb paresis was found to have parelaphostrongylosis. Despite treatment with ivermectin, fenbendazole, cimetidine, and ceftiofur, the llama developed gastrointestinal ulceration and pulmonary aspergillosis and was euthanatized. Parelaphostrongylus tenuis is a parasite of white-tailed deer, but ruminants can serve as aberrant or dead-end hosts after accidentally ingesting snails or slugs carrying third-stage larvae of the parasite. Gastrointestinal ulceration and pulmonary aspergillosis can develop secondarily in llamas with chronic disease. Treatment of gastrointestinal ulceration in llamas is difficult, because efficacy of commonly used antiulcer drugs in llamas has not been established.

A 9 month old female llama was presented with inspiratory dyspnea. Radiographically, there was a large soft tissue mass nearly occluding the nasopharynx. During endoscopic examination three nasopharyngeal bots were identified embedded in the mass. The larvae were removed and the patient treated with ivermectin. The patient was discharged one week later free of clinical respiratory disease. In follow-up radiographs made 6 weeks later, only residual radiopacity in the area of the mass remained.

Alpaca (Lama pacos) were grazed for 10 months (October 1992-June 1993) on pasture with sheep or on pasture which had been recently grazed by sheep. The alpaca, of various age groups, totalled 94 at the beginning of the experiment and during the course of the experiment 32 progeny (cria) were born, 10 in spring 1992 and 22 in autumn 1993. Serum levels of specific antibodies to excretory/secretory antigens of the third larval stage (L3) of Cooperia curticei, Ostertagia circumcincta or Trichostrongylus colubriformis and somatic antigens from adult T. colubriformis were determined at monthly intervals by ELISA. Faecal egg count and live-weight were determined monthly and fleece-weight was measured at shearing. Three days after the birth of the cria, serum antibody levels ranged from 0.46-0.85 optical density units for the L3 antigens and averaged 0.22 for the adult T. colubriformis antigen. These levels declined to 0.1-0.24 and 0.06 respectively by 2-3 months of age. Subsequently, antibody levels increased steadily to reach maximal adult levels at approximately 23-26 months. Antibody levels were negatively correlated with FEC, but positively correlated with live-weight at 7 months although at 15 months antibodies and live-weight were negatively correlated. A positive correlation was found between weight and FEC. Fleece-weight showed no correlation with antibody level, a positive correlation with weight and a negative correlation with FEC. The relationships among antibody responses, FEC, live-weight and fleece-weight observed for alpaca in this experiment suggest that antibody responses might provide a useful indicator of alpaca immuno-responsiveness and has potential for use as a parameter for selection of alpaca with reduced FEC.

A microenzyme-linked immunosorbent assay (dot-ELISA) was developed to detect serum antibodies against Fasciola hepatica antigens in llamas. Sera from five F. hepatica-infected and 11 non-infected llamas were used in initial test development. Nitrocellulose filter disks containing F. hepatica excretory-secretory product were placed in 96-well microtiter plates, washed, blocked with Tween-20, then incubated with four-fold serial dilutions of llama sera. After incubation with rabbit anti-llama IgG followed by peroxidase-conjugated goat anti-rabbit IgG, addition of precipitable substrate resulted in purple dots on white background (positives) easily read by eye. The technique was further evaluated at titers of 1:512 using an additional six known positive and eight known negative llamas. Test results showed 6/6 known positive as positive and 8/8 known negative as negative. Sera were collected, at approximately weekly intervals, from three llamas experimentally infected with F. hepatica. The dot-ELISA detected antibodies to F. hepatica as early as the second week post-infection in all llamas. In a serologic survey of 256 llamas from an F. hepatica endemic area, the dot-ELISA detected antigen-specific serum antibodies to F. hepatica in 42 (16%) of the llamas. Although no difference was noted in antibody prevalence between sexes, prevalence increased in llamas over 6 months of age.

Lamoids in North America harbor a wide variety of parasites. Treatment and control methods based on previous experience with parasites of cattle and sheep have been successful, but problems do exist. First, the pharmacokinetics for most anthelmintics have not been evaluated in llamas. Second, even though llamas, sheep, and cattle share many parasites, the two most common nematodes found in llamas (C. mentulatus and T. tenuis) are not part of the parasitic fauna of livestock. This presents difficulties in basing treatment and control methods on those recommended for cattle and sheep. Variability in host response to the same parasite also hinders the use of cattle and sheep as models for the llama. This is best demonstrated by F. magna and F. hepatica; the reaction induced by the first more closely resembles those seen in cattle than sheep, but the reaction induced by the second more closely resembles those seen in sheep than cattle. Finally, parasites known to be pathogenic in livestock (e.g., N. battus) have unknown effects in llamas. These examples illustrate that we must use caution when extrapolating existing knowledge regarding the parasites of sheep and cattle to llamas. Further research on the epidemiology of parasites peculiar to the llama is needed to enhance control efforts. Improved methods of diagnosis and treatment of parasites also are areas in which further efforts are needed.

A 7-year-old female llama was experimentally infected with 500 Fasciola hepatica metacercariae then turned out onto pasture also grazed by domestic sheep. The llama was necropsied approximately 22 weeks post infection. Routine examination of the gastrointestinal tract revealed diffusely coalescing, umbilicated nodules covering the caudal one-fifth of the third stomach compartment. Microscopically, the mucosa was irregularly thickened. Numerous nematode larvae were present in glandular lumens, often extending to the base of the glands. Where nematodes were most numerous, decreased numbers of parietal cells, attenuation of glandular epithelium and increased collagen within the lamina propria were evident. Of a total of 6510 adult nematodes in the third stomach compartment, 51% were Teladorsagia spp., 47% were Trichostrongylus axei, and 2% were Camelostrongylus mentulatus. Except for C. mentulatus, three sheep that had grazed with the llama and were necropsied at approximately the same time, harbored the same nematode species. The total number of larvae in the llama was 56,710, with more than 97% being ostertagiine early fourth-stage larvae. Ostertagiine larvae were also present in the sheep. Based on the composition of the adult populations in the llama and sheep, the larvae were considered to be species of Teladorsagia. Additionally, the larger numbers of early fourth-stage larvae indicated that the development of Teladorsagia spp. in the llama is inhibited.

Serum samples from 283 llamas (Lama glama) from Oregon, Washington State and Idaho were tested for antibodies to Toxoplasma gondii using the modified agglutination test. Antibodies were found in 95 (33.5%) llamas. Percent seropositivity in serum dilutions of 1:25, 1:50, 1:500, and 1:5000 was 9.5%, 18.3%, 4.9%, and 0.7%, respectively.

Four llamas (Lama glama) ranging in age from 1.5 yr to 7 yr each were inoculated orally with 10,000 (n = 2) or 50,000 (n = 2) sporulated oocysts of Eimeria alpacae (25%) and Eimeria punoensis (75%). The prepatent period for E. aplacae was 16-18 days, and it was 10 days for E. punoensis. Patent periods for E. alpacae and E. punoensis were approximately 9 days and 24 days, respectively. Although large numbers of oocysts were present in feces, no clinical sign of coccidiosis was observed. Based on ths experiment, E. alpacae and E. punoensis at the numbers given are not likely pathogenic in healthy llamas older than 1 yr.

A trial was carried out in alpacas (Lama pacos) and llamas (Lama glama) to determine the economic benefits of controlling both external and internal parasites by the use of ivermectin ("Ivomec," Merck Sharp & Dohme). After four months the treated male alpacas gained on average 3.1 kg more than the untreated males, and their fleece weighed 0.36 kg more. The treated female alpacas gained 1.9 kg more than the controls, but their fleece weighed 0.03 kg less. This treatment gave a net financial benefit to the farmer of U.S. $3.54 for each of his male alpacas and U.S. $1.36 for each of his female alpacas. The results for the llamas were not significant because there was great variation in the weight gains (and losses). Because the value of llama fleece is less, the economic benefits were also less.

A trial was carried out in alpacas (Lama pacos) to determine the economic benefit of controlling both external and internal parasites using ivermectin (Ivomec, Merck, Sharpe and Dohme). After four months the treated male alpacas had gained on average 3.1 kg more than the untreated males and their fleece weighed 0.36 kg more. Treated females gained 1.9 kg more than the controls but their fleece weighed 0.03 kg less. This resulted in a net financial benefit to the farmer of US$3.54 for each male alpaca and US$1.36 for each female.

Psoroptes sp. mites were isolated from two llamas (Lama glama), a 4-mo-old male and its dam, in Washington. Mites were restricted to the ears and were responsible for head-shaking and incoordination. Infestations were treated successfully with a subcutaneous injection of ivermectin at 0.2 mg/kg of body weight and with 2 drops of ivermectin diluted in saline given topically in each ear. This is the first known report of Psoroptes sp. in llamas in the United States.

Various protein separation techniques have been used as alternative means of differentiating species and strains of parasites. Of these techniques, isoelectric focusing (IEF) has proved to be specific and reproducible with cestodes, protozoa and trematodes. As with the traditional morphological approach, there is, however, the potential for host influence. For a particular separation technique to be useful, it is important that banding profiles differentiating parasites be consistent, regardless of host species. To test for host influence, Fasciola hepatica were maintained in four definitive hosts. Soluble proteins of flukes from different hosts and their respective excretory-secretory product (ESP) were then subjected to IEF together with respective host tissues, and the resulting banding patterns were compared. Protein banding profiles of fluke body protein from llama, rat and mouse were very similar, while those of flukes from calves were distinct. Banding patterns of fluke ESP from different hosts were dissimilar. Overall banding patterns of body protein and ESP of flukes from different hosts were distinct from those of respective host tissues. The unique banding patterns of the body protein of flukes from calves indicate that there was host influence in their protein banding patterns, and the uniqueness of the calf fluke is discussed relative to host's resistance to the fluke.

Fecal samples were collected from 144 llamas, Lama glama, on four premises in northern Colorado and southern Wyoming. Feces were examined for the presence of coccidial oocysts; Eimeria alpacae was found in 55.6%, Eimeria lamae in 67.3% and Eimeria macusaniensis in 1.4% of the samples. An adult female llama was found to be infected with Eimeria macusaniensis at necropsy. This is the first report of these species of coccidia in the llama.

For the control of scabies in tylopodes (L. bactrianus, L. guanicoe, L. glama) and brown bears 0.2 mg/kg body weight (1 ml/50 kg body weight) of Ivermectin subcutaneously injected proved to be remedy of choice. In Kodiak-bears the oral application of Ivomec-solution was effective against ascariasis, not, however, in polar bears. Sufficient effect was reached only once, whereas Equalan-paste proved to be highly effective. Despite of strong hygienic measures continous follow-up treatment for the prevention of re-invasion is indispensible.

Whipworms collected from llamas (Lama glama) in Oregon were identified as Trichuris tenuis Chandler, 1930. A redescription, based on the specimens collected from llamas and examination of the paratypes, is presented. The unique form of the cloaca in T. tenuis separates males of this species from all other species of Trichuris known to occur in ruminants. Among species of Trichuris for which adequate descriptions of the female exist, T. tenuis can be distinguished using an array of characters including an uneverted, aspinous vulva and a highly convoluted vagina with papillalike spines in the proximal one-fourth and a small egg chamber located approximately midway along its length. This constitutes only the second report of T. tenuis in North America and brings to 7 the number of species of Trichuris known to occur in sylvatic and domestic ruminants in North America.

The biology of the Sarcocystis sp. that infect guanacoes was studied by feeding the infected meat to dogs, cats, rats and mice. Tissues from guanaco, heavily infected with macrocysts, were fed to these animals and their faeces collected daily and examined for the presence or absence of sporocysts. It was shown that only dogs were suitable definitive hosts. The effect of cooking and freezing on the viability of this protozoan organism was also investigated. Freezing to -18 degrees C and -24 degrees C and cooking were effective for inactivating Sarcocystis in guanaco meat. These methods could therefore be used instead of condemning guanaco carcasses infected with Sarcocystis.