Clinical findings and risk factors associated with the first report of Eimeria macusaniensis

In July 2005, the coccidian parasite Eimeria
macusaniensis was detected in New
Zealand alpacas. This paper describes the investigation
that followed the discovery.
Clinical findings and risk
factors associated with
the first report of Eimeria
macusaniensis in New Zealand
alpacas
Three coccidian species – Eimeria lamae, Eimeria alpacae and
Eimeria punonensis – have previously been reported in camelids in
New Zealand(1)(2)(3).
On 29 July 2005, a pathologist at Gribbles Veterinary Pathology
notified MAF of a suspected identification of E macusaniensis
in the faeces of a ten-year-old female alpaca.
The diagnosis was subsequently confirmed by a Biosecurity New
Zealand reference parasitologist.
At the start of the investigation, Biosecurity New Zealand
considered the coccidian to be a new incursion and, because of its
reputed pathogenicity(4)(5), declared it an unwanted organism under
the Biosecurity Act 1993. A measured response was initiated on 10
August 2005 with four objectives:
• to prevent spread of E macusaniensis by implementing interim
containment measures on the properties that received alpacas
from the affected import consignment,
• to complete a cross-sectional survey of camelids on affected
properties to detect those shedding E macusaniensis, and assist in
understanding the epidemiology of this parasite in New Zealand,
• to collect and assess case history data for ill alpacas in recent
import consignments,
• to commission Biosecurity New Zealand’s reference parasitologist
to review the literature on E macusaniensis, including its
potential pathogenicity (published in this edition(6)).
Interim containment
Movements of all camelids and their faecal material were restricted
on to and off the four properties suspected of having affected
animals. To enforce these measures each property was issued a
Restricted Place notice under s130 of the Biosecurity Act 1993.
AgriQuality Limited provided a Restricted Place Manager (RPM)
for each property to help manage the conditions of the Restricted
Place notice, and fulfil duties in accordance with MAF Standard
153 (Response Programs for Exotic Diseases of Animals, October
2004).
Cross-sectional survey
A cross-sectional survey was used to help elucidate the
epidemiology of E macusaniensis on affected properties. The survey
categorised the animals shedding E macusaniensis into four at-risk
groups:
• alpacas from the May import consignment,
• alpacas from previous import consignments,
• alpacas exposed to the May import consignment,
• alpacas not exposed to the May import consignment.
A fifth South Island farm with a single E macusaniensis positive
animal was identified through passive laboratory surveillance
around the time of the response, and was also included in the
cross-sectional survey. This property had been run as a closed flock
for a number of years and had no contact with recently imported
animals or the four infected places.
Faecal samples were collected from all alpacas older than three
months, with the exception of those close to parturition. The
census sampling was intended to provide a 95% confidence of
detecting at least a 2% prevalence of shedding animals in the
smallest of the five risk groups. A prevalence of 2% represents
the lower 95% confidence interval for prevalence determined in a
survey by Jarvinen(7) in the northwestern United Sates.
A sealable plastic bag was inverted and used as a glove for per
rectum collection of faeces. Samples were delivered the same day
to the laboratory and a faecal sedimentation technique used to
detect coccidial oocysts. Because of the large size of
E macusaniensis oocysts, faecal sedimentation is considered a more
sensitive technique than faecal flotation(7). All at-risk farms were
sampled in mid-August 2005.
Univariate analysis using chi-squared or Fisher’s exact methods
were used to explore the data for potential explanatory variables
associated with faecal shedding of E macusaniensis oocysts.
Analysis was undertaken using STATA 7.0 (Stata Corporation,
USA). A p-value less than 0.05 was considered significant.
Survey results
Prevalence of shedding
On the first four at-risk farms, 427 alpacas were sampled and 14
animals determined to be shedding (Table 1). A further 33 animals
were sampled on Farm 5 where a single animal had been identified
as shedding. Inter-farm prevalence of shedding ranged between
0.61% and 7.55% (Table 1, Fisher’s exact p = 0.033).
Table 1: The intra-farm prevalence of alpacas shedding Eimeria macusaniensis oocysts
on the five affected farms
Farm 1 Farm 2 Farm 3 Farm 4 Farm 5 Total
Date sampled
(2005)
12 August 15 August 12 August 15 August 25 and 29 August
Number sampled 164 1211 107 35 33 460
Positive
1
(0.61%)
81
(6.61%)
3
(2.80%)
2
(5.71%)
1
(3.03%)
15
(3.26%)
Fisher’s exact p-value = 0.033
1 Findings from a mob of 15 animals imported from Australia on to Farm 2 on 19 July were excluded from the summary figures above and in Table 1.
Table 2: Univariate analysis of risk factors for shedding of Eimeria macusaniensis
determined after investigation of five affected farms
Risk factor +ve
(prevalence of infection)
Risk factor -ve p-value
Risk factors for shedding
Univariate analysis was carried out to assess risk factors for
E macusaniensis shedding in individual alpacas. As noted in the
footnote to Table 1, findings from the mob of 15 animals imported
on to Farm 2 in July were excluded from this analysis. This was
because the prepatent period for E macusaniensis of 32-40 days
would mean infection in these animals would have taken place
before their entry into New Zealand(8). Six of the 15 (40%) animals
in this group were found to be shedding E macusaniensis oocysts.
Shedding was significantly associated with age (<12 months) and exposure to the May import consignment. Factors not significantly associated with shedding were sex, the import status of the animal, or whether the animal belonged to the May consignment (Table 2). There was no difference in the proportion exposed in the two age groups. Case history summaries Case history (clinical, necropsy and laboratory) data was available for four ill alpacas from recent import consignments. Eimeria macusaniensis was not implicated as the cause of death in a cria and two adults from the May import consignment, but was determined to be the cause of death of an alpaca in a July consignment. Hypothermia with terminal aspiration of stomach content was responsible for the death of the cria, and chronic liver disease was identified as the cause of death in the two adults from the May consignment. In one animal the aetiology of the liver pathology was not evident, and a toxic origin appeared likely in the remaining adult. The death of the alpaca from the July consignment was attributed to the severe gut pathology associated with infection by E macusaniensis. The key findings in this case are summarised below. This animal was an Australian bred adult female alpaca imported on to a Canterbury alpaca farm on 19 July 2005, after 30 days quarantine in Victoria, Australia. The farmer was experienced with alpacas, having successfully imported, bred and shown them for five years. On 14 August 2005, the farmer observed the animal to be in light condition (estimated condition score: 2-2.5) with loose (semi-solid) faeces. The farmer treated the animal with an oral coccidiocide (off-label use) but it died on 17 August. At MAF’s request, the farmer’s veterinarian carried out a postmortem, and collected samples for biochemical, faecal and histological analysis. Necropsy showed small intestinal gastroenteritis and enlarged mesenteric lymph nodes. The carcass was otherwise grossly normal. Significant histological lesions (Figures 1 and 2) were confined to the gastrointestinal tract. Occasional coccidial cysts were identified in the duodenum. The ileum was affected by a severe coccidial infestation with suppurative enteritis and multifocal ulceration. Large numbers of various stages (oocysts, schizonts, etc) of coccidia were present in the lamina propria. The number of crypts was reduced, with villi shortened and the sides of some villi covered in a flattened epithelium. The area of the basal lamina propria and muscularis mucosa had neutrophils and macrophage infiltrates with the reaction extending through the submucosa to affect the tunica muscularis in places. The rest of the submucosa had areas of oedema and widespread infiltration of neutrophils, macrophages and plasma cells. Multiple foci of ulceration were also present with ulcers filled with necrotic debris, bacteria and neutrophils. The spiral colon and large intestine had no significant lesions. Serum was collected at postmortem. Reduced blood albumen (20 g/l) and total protein (40 g/l) were consistent with a proteinlosing enteropathy. Elevated blood creatine (441 μmol/l), urea (33.6 mmol/l) and phosphate (5.71 mmol/l) were considered to have resulted from dehydration. Faecal sedimentation identified abundant (+++) E macusaniensis oocysts. Faecal culture for salmonella was negative. Discussion There have been conflicting reports in the literature of the importance of this protozoan. Clinical disease in individuals and groups appears to occur only sporadically, and when it does it is often associated with stress and/or poor management. Generally infection is subclinical with a low herd prevalence of faecal oocyst shedding (Jones J, UK, personal communication; Cebra C, USA, personal communication)(4). The range in herd shedding identified in the New Zealand investigation (0.61% to 6.61%) was comparable with that found in overseas studies(7)(9)(10). The range differed significantly among the New Zealand study farms (p = 0.033; Table 1). The cross-sectional survey identified age (less than 12 months) and exposure to the May import consignment as significant factors influencing shedding (Table 2). Eimeria macusaniensis is generally associated with clinical disease in young animals(11) and has been associated with death in neonatal alpacas in South America(5). A higher prevalence of shedding has been noted in young llamas(7)(8) although this has not previously been substantiated in alpacas. Management factors associated with importing animals are likely to increase susceptibility to E macusaniensis(12) and lead to increased rates of shedding with resultant contamination of the environment and exposure of other animals. The risk associated with recently imported animals is supported by the finding of a 40% prevalence of shedding in the July import group, sampled within a few weeks of their arrival. Stress factors involved in importing include confinement in quarantine, a change in ration, international and national transport, and acclimatisation to a new environment, management system and peer group in New Zealand. This assessment found a significant difference in the prevalence of the two risk factors, identified at the individual animal level, across the five farms. The proportion of cria in the flock ranged between 4.3% and 26.5% (p<0.001), while the proportion of alpacas exposed to the May imports ranged between 0% and 92.6% (p<0.001). The worst affected farm (Farm 2) had the highest proportion of cria and also the highest proportion of individuals exposed to the May import consignment. Investigators identified a number of management differences (farm-level risk factors) that are likely to influence prevalence and that may have affected the relationships identified at the individual animal level. These include variability of faecal pick-up by the farmer, differences in stocking density, paddock management that encourages midden formation, grazing system (Figure 3) and the numbers of recently imported animals. A further factor that Figure 1: Section of ileum showing multifocal ulceration, reduced crypt formation, neutrophil, macrophage and plasma cells infiltrates in the muscularis mucosa and submucosa, and large numbers of various life stages of Eimeria macusaniensis in the lamina propria (x40) Figure 2: Section of ileum showing numerous developing stages of Eimeria macusaniensis in the lamina propria, including meront (M) and thick-walled oocysts (O) (x400) would affect the resident animals’ exposure is the variability of quarantine period imposed on new arrivals. For alpaca imports, this separation traditionally serves the purpose of ensuring more intensive management of the imports as they recover from the stresses of importation but also importantly serves to protect resident stock from introduced diseases or parasites. The severely affected animal described in the case report appears typical of sporadic cases reported from Australia(4), the USA (Cebra C, personal communication) and the United Kingdom(13). Eimeria macusaniensis infestation predominates in the ileum with dramatic parasite numbers obliterating normal intestinal architecture. Secondary changes include necrotising and/or bacterial enteritis, and multifocal ulceration. Most pathology occurs in the small intestine, leading to weight loss and hypoproteinaemia. As a result sick alpacas may present with acute weakness or sudden death. Diarrhoea is not a frequent finding (Jones J, personal communication)(4). During the investigation it became apparent that this was not the first incursion of E macusaniensis. Evidence included the presence of E macusaniensis in alpacas not exposed to the May consignment on two of the four affected farms, a retrospective Australian quarantine report of the coccidian in alpacas destined for New Zealand in April 2004 (a finding identified at a review of Australian quarantine test results, requested by MAF as part of this investigation), and the detection of E macusaniensis in an alpaca on a fifth farm that was not associated with the others. New Zealand Import Health Standards have never required testing and/or prophylactic treatment for this parasite. Since this organism did not appear to be a recent introduction to New Zealand, and as its pathogenicity may have been overstated in the literature, MAF removed interim containment measures on the affected farms. The findings of this investigation are a reminder that import testing protocols do not exclude all diseases and pests, that farmers should remain vigilant and take measures to protect resident stock and report anything unusual to MAF through the 0800 809 966 exotic disease and pest freephone. Acknowledgements The authors would like to thank all Gribbles Veterinary Pathology staff, veterinarians, AgriQuality Limited field personnel, and Biosecurity New Zealand’s Pre Clearance team, who contributed during the initial investigation and follow-up survey. The invaluable input of Marsha Stevens and Rob Fairley (Gribbles Veterinary Pathology Christchurch), Melanie Taylor and John Gill (Gribbles Veterinary Pathology Invermay) and Donald Arthur (Selwyn Rakaia Veterinary Services) is especially acknowledged. Alastair Johnstone (Institute of Veterinary, Animal and Biomedical Sciences, Massey University) is also acknowledged for providing photographs of the histology sections. References (1) Guerrero C. Coccidia (Protozoa: Eimeriidae) of Alpaca Lama pacos. Journal of Protozoology 14, 613-6, 1967. (2) Guerrero C, Hernandez J, Bazalar H, Alva J. Eimeria macusaniensis (Protozoa: Eimeriidae) of the alpaca Lama pacos. Journal of Protozoology 18, 162-3. 1971. (3) McKenna PB. Some new host-parasite records. Surveillance 28(1), 4-5, 2001. (4) Lenghaus C, O’Callaghan MG, Rogers C. Coccidiosis and sudden death in an adult alpaca (Lama pacos). Australian Veterinary Journal 82, 711-2, 2004. (5) Rosadio RH, Ameghino EF. Coccidial infections in neonatal Peruvian alpacas. Veterinary Record 135, 459-60, 1994. (6) McKenna PB. Eimeria macusaniensis in camelids - a brief review. Surveillance 33(4), 8-10, 2006. (7) Jarvinen JA. Prevalence of Eimeria macusaniensis (Apicomplexa: Eimeriidae) in midwestern Lama spp. Journal of Parasitology 85, 373-6, 1999. (8) Rohbeck S, Gauly M, Bauer C. On the biology of Eimeria macusaniensis, an intestinal parasite of South American camelids. 19th International Conference of the World Association for the Advancement of Veterinary Parasitology. New Orleans, USA, 2003. (9) Rickard LG, Bishop JK. Prevalence of Eimeria spp. (Apicomplexa: Eimeriidae) in Oregon llamas. Journal of Protozoology 35, 335-6, 1988. (10) Schrey CF, Abbott TA, Stewart VA, Marquardt WC. Coccidia of the llama, Lama glama, in Colorado and Wyoming. Veterinary Parasitology 40, 21-8, 1991. (11) Leguia G. The epidemiology and economic impact of llama parasites. Parasitology Today 7, 54-6, 1991. (12) Rickard L. Update on Llama medicine: Parasites. Veterinary Clinics of North America: Food Animal Practice 10, 239-47, 1994. (13) Chief Veterinary Officer, U.K. The Report of the Chief Veterinary Officer - Animal Health 2004. 2004. Thomas Rawdon Andrew McFadden Caleb King Investigation and Diagnostic Centre (Wallaceville) Biosecurity New Zealand PO Box 40 742 Upper Hutt Email: Thomas.Rawdon@maf.govt.nz Verona Mitchell Mosgiel Veterinary Services Limited 4 Cargill Street Mosgiel Mark Howell Surveillance and Incursion Response Biosecurity New Zealand Wellington
I would like it noted, that all alpacas are checked in quarantine for all parasites, and coccidia, liver fluke and salmonella.

All counts are also taken if any are found., and treatment is required and retested to confirm any alpaca in quarantine destined for export to NZ, will be zero for all tests.
These tests until death of Paul Presedente, were tested by Paul himself, and since by technicians taught by Paul.
These tests are all completed by Australian GOvernment Laboratories, and all alpacas are zero for EMAC, and any other coccidia, as well as Liver Fluke, Salmonella (tested twice), and stomach parasites, as well as mites, and ectoparasites.

eimeria macusaniensis- EMAC in Alpacas PT 2

(taken from the same Survellience notes, (MAF NZ 2006), as in previous post- i hope this is of some help.
Eimeria macusaniensis in
camelids – a brief review
Of the four or five coccidial parasites known to infect llamas and
alpacas, namely Eimeria lamae, E alpacae, E punonensis, E ivitaensis
and E macusaniensis(1)(2)(3), only the first three have previously been
recorded in New Zealand(4). However, in July 2005 oocysts of
E macusaniensis were detected in the faeces of a ten-year-old female
alpaca on a property in Otago, approximately eight weeks after its
importation from Australia. Because of the supposed pathogenicity
of this protozoan, a limited survey was undertaken to determine its
presence elsewhere in New Zealand(5). Its general biology is briefly
reviewed here.
Host specificity
All mammalian coccidia are considered to be quite host specific.
Thus coccidia of camelids are not infective to other domestic or wild
ruminants and those of the latter hosts will not infect camelids(6)(7).
Because of their genetic relatedness, it is generally accepted that all
camelids share the same species of coccidia. Thus E macusaniensis
infections have been recorded in alpacas (Vicugna pacos), llamas
(Lama glama), guanacos (Lama guanicoe)(8)(9) and vicunas (Vicugna
vicugna)(10). It has also been observed that both the oocyst and
the endogenous stages of E macusaniensis are almost identical to
those of E cameli of the dromedary (Camelus dromedarius) and
the bactrian camel (Camelus bactrianus)(11). This has prompted
speculation that these two coccidians might eventually be revealed
to be the same species (Duszynski et al. The coccidia of the World.
http://biology.unm.edu/biology/coccidia/home.html).
Distribution and prevalence
Infections of E macusaniensis have been reported in camelids in
Australia(12), North America(8)(11)(13), South America(2)(14), the United
Kingdom(15) and Germany(16). While most of these reports have
involved llamas, in some instances they include alpacas and guanacos
as well. In the United States, infections of E macusaniensis were found
in two of 144 (1.4%) llamas from Colorado and Wyoming(11) and in
two of 189 (1.0%) adult llamas in Oregon(13). A prevalence of 12%
was also recorded in 301 llamas from the midwestern United States(8).
There have been fewer investigations of the frequency of occurrence
of E macusaniensis infection in the other hosts but prevalences
of about 7% were found in 115 alpacas and 27 guanacos in the
midwestern United States(8). In other surveys, oocysts of
E macusaniensis were found in the faeces of 24% of 160 alpacas in
Peru(15) and in nine of 12 guanacos examined in Patagonia(17).
Although infections with E macusaniensis may be found in
both adult and younger hosts, the latter group tends to be more
frequently involved. Thus the highest prevalence of infection (67-
71%) was found in llamas of two and three months of age on a farm
in Germany, with somewhat lower levels of infection (16% and 26%,
respectively) recorded in mature dams and yearling males(16). Others
have reported similar results with prevalences significantly greater in
animals less than one year of age than in older animals, both in the
midwestern United States(8) and in Peru(17).
So far, E macusaniensis has been recorded on only a limited number
of properties in New Zealand and these have largely involved
infections in alpacas recently imported from Australia(5). However,
infections with other coccidial species have been detected in
previous importations(4) and it is difficult to believe that
E macusaniensis would somehow be selectively excluded from
these. Indeed, a far more likely scenario is simply that its presence
remained undetected either because fewer oocysts were present and/
or because of the low sensitivity of the examination procedure used
to detect them (see below). If this is correct, then it is possible that
the parasite has been present here for a number of years.
Life cycle and development
The life cycle of E macusaniensis is that of a typical coccidian
with infection initiated by the ingestion of sporulated oocysts
and endogenous development taking place in the small intestine
of infected hosts. Here there is a period of asexual reproduction
(schizogony or merogony) within epithelial cells, followed by sexual
differentiation (gametogony) into male microgametes and female
macrogametes that give rise to unsporulated oocysts, which are
shed in the faeces. By a process of sporogony or sporulation, four
sporocysts each containing two sporozoites are formed within the
oocyst, which then typically serves as the only source of infection for
all potential hosts.
Asexual and sexual reproduction do not continue indefinitely within
the host and, in the absence of reinfection, coccidial infections are
self-limiting in duration. Reinfection may take place but usually the
host develops a degree of immunity following primary infection.
In experimentally infected llamas, the interval between the ingestion
of sporulated oocysts of E macusaniensis and the subsequent first
appearance of unsporulated oocysts in their faeces (the pre-patent
period) was found to be 32-36 days. Oocyst shedding continued for
39-43 days with a mean total output during this patent period of 3-10
million oocysts. Reinfection two or three weeks after the end of the
first patency resulted in a prolonged pre-patent period of 37-40 days, a
shortened patent period of 20-23 days and a reduced oocyst output(16).
The time taken for oocysts excreted in the faeces to undergo and
complete sporulation, and thus become infective for other hosts, is
largely temperature and oxygen dependent and for most coccidial
In 2005, oocysts of Eimeria macusaniensis were
detected in the faeces of an alpaca in Otago. This
article briefly reviews the organism, its distribution, life
cycle and pathogenicity, and methods for its detection,
management and control.
page 8
species occurs within the range of 10-30oC. In the case of
E macusaniensis, sporulation has been found to take 12-15 days at
23oC(13). Others(16) report that the maximum number of sporulated
oocysts (85%) was obtained after 15 days at 30oC and after 25 days at
16-18oC.
Diagnosis and detection
The diagnosis of E macusaniensis infection is largely based on
the detection of oocysts in host faeces. These may be readily
differentiated from the oocysts of the other coccidial species that
may be found in the faeces of llamas and alpacas by their greater size
(three to four times larger), brown colour, and prominent micropyle.
Detailed descriptions of the oocysts of all these species are provided
elsewhere(1)(2) but, briefly, those of E macusaniensis are pyriform in
shape and measure 80-110 μm long by 60-80 μm wide. They also
have very thick oocyst walls approximately 8-12 μm thick(11).
Like other coccidia, E macusaniensis oocysts may be detected by
standard flotation techniques. However, because of their large
size, flotation solutions with specific gravities of ≤ 1.2 may fail to
detect E macusaniensis infections and those with specific gravities
of 1.28-1.3 are required(8). Such oocysts may also be detected by
a sedimentation technique. Indeed, the latter technique, which is
likely to provide a more sensitive faecal examination procedure(2)(8),
represents the method of choice.
It is also important to note for diagnostic purposes that oocysts of
E macusaniensis are unlikely to be present in the faeces of animals less
than one month of age since the prepatent period is greater than 30
days. An epidemiological study in Germany, for example, found that
oocyst shedding was first detected when animals were two months
old(16). In addition, because of the long pre-patent period, it is possible
that acutely infected animals could die before oocysts are present in
their faeces. Although infection may sometimes be accompanied by
enteritis and diarrhoea(7), commonly few clinical signs are apparent(8).
In such cases, diagnosis depends on the histopathological examination
of the small intestine and the demonstration of schizonts, gametocytes
and oocysts in epithelial cells(12)(14).
Pathogenicity
Most coccidial infections in llamas and alpacas are described as
asymptomatic and self-limiting(6)(7). However, young animals may
show signs of clinical coccidiosis when faced with heavy infections
and at times of stress, and two of the coccidial species most frequently
associated with such outbreaks are E lamae and E macusaniensis(10). In
addition, co-infections of E ivitaensis and E macusaniensis have also
recently been implicated in fatal cases of diarrhoea in young alpacas
in Peru(18). Despite this, information relating to the pathogenicity
of E macusaniensis remains somewhat contradictory and confusing.
Thus in the paper of Rosadio and Ameghino(14), Guerrero et al(19) and
Guerrero and Leguia(20) are cited as suggesting that E macusaniensis is
minimally pathogenic. However, in the same paper J Alva is reported,
in a personal communication, as has having identified ‘clinical cases
caused by this organism in association with natural outbreaks of
diarrhoea in southern Peru’.
Other authors(17)(21) cited in the papers of Rickard and Bishop(13)
and Foreyt and Lagerquist(22) also consider that E macusaniensis is
pathogenic for alpacas, a conclusion supported by the reports of
Rosadio and Ameghino(14) and Lenghaus et al(12). The latter authors
certainly believed their report confirmed that E macusaniensis was
highly pathogenic in alpacas and that coccidiosis resulting in severe
damage to intestinal epithelia predisposes to necrotising enteritis
and death. Somewhat similar views were expressed by Leguia(10)
who considered that coccidiosis was mainly a problem of alpacas
reared in confinement but that frequent outbreaks of subacute
or acute infections occurred in animals born late in the breeding
season in Peru. He stated that such outbreaks seemed to be mainly
caused by infections of E lamae associated with E macusaniensis.
Such co-infections he considered to be highly pathogenic since
the first species destroyed the intestinal epithelium while the
second damaged the crypt glands and inhibited regeneration of the
epithelium. This resulted in complete stripping of the intestinal
mucosa and its total loss of function, leaving the intestinal wall
exposed to secondary viral or bacterial invasion. He(10) believed,
therefore, that there was a strong correlation between coccidiosis and
bacillary enterotoxaemia, which resulted in up to 50% mortality in
newborn animals in that country.
While enteritis has also been associated with E macusaniensis
infections in a three-month-old guanaco and an adult alpaca,
these infections were considered incidental findings at necropsy(7).
Jarvinen(8) also points out that the contribution of other pathogens
was not considered in the Rosadio and Ameghino(14) case. The same
author(8) further stated that the pathogenicity of E macusaniensis
had not been evaluated in controlled studies using experimentally
induced infections. Certainly, no clinical signs were associated with
infections in llamas in Jarvinen’s survey(8). However, others(16) have
since carried out experimental infections in llamas. In this latter
study, five one-month-old llamas, reared parasite-free, were orally
infected with 20,000 E macusaniensis oocysts while another twomonth-
old animal received 100,000. Although, the primary purpose
was to study the parasite’s pre-patent and patent periods, one would
have expected that any associated health issues would also have been
reported. The fact they were not, suggests that none were observed.
In summary, it would appear that while E macusaniensis may have
the potential to cause death and disease in both young and adult
camelids, the frequency with which it is likely to do so may have
been somewhat overstated.
Management and control
There is no published information relating specifically to the
longevity and survival of E macusaniensis oocysts. However,
coccidial oocysts are generally considered hardy long-lived resting
stages capable of withstanding the action of many chemical andphysical agents and it is likely the thick walls of those of
E macusaniensis make them particularly resistant to such challenges.
Once oocysts of this species are present in the environment,
decontamination of affected properties is, therefore, likely to be
difficult. Possibly some measure of control could be achieved by
a combination of faecal removal and animal treatment but total
eradication of infection from affected farms would appear to be an
unrealistic proposition.
In addition to exposure to the organism, clinical coccidiosis in
camelids is generally linked to a combination of stress factors
including weaning, overcrowding, cold, travel and poor nutrition(7).
Good management is, therefore, likely to be the key to preventing
infection with E macusaniensis becoming too much of a problem
on individual properties. Obviously the treatment of infections may
play a part as well but since no anticoccidials are registered for use
in camelids in New Zealand, this may be somewhat problematic.
Nevertheless, toltrazuril (Baycox, Bayer New Zealand Ltd), which is
registered for use in poultry and piglets here, is likely to represent
the best candidate. Previous studies have shown that this drug,
usually administered at a dose rate of 20 mg/kg, is effective against
all intracellular life cycle stages of a variety of other coccidial species
in a number of mammalian hosts(23).
References
(1) Guerrero CA. Coccidia (Protozoa: Eimeriidae) of the Alpaca Lama pacos.
Journal of Protozoology 14, 613-6, 1967.
(2) Guerrero CA, Hernandez J, Bazalar H, Alva J. Eimeria macusaniensis n.sp.
(Protozoa: Eimeriidae) of the alpaca Lama pacos. Journal of Protozoology 18,
162-3, 1971.
(3) Leguia G, Casas E. Eimeria ivitaensis (Protozoa: Eimeridae) en alpacas (Lama
pacos). Revista Peruana de Parasitologia 13, 59-61, 1998.
(4) McKenna PB. Register of new host-parasite records. Surveillance 28(4), 4-5,
2001.
(5) Rawdon T, McFadden A, King K, Mitchell V, Howell M. Clinical findings and
risk factors associated with the first report of Eimeria macusaniensis in New
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in midwestern Lama spp. Journal of Parasitology 85, 373-6, 1999.
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adult alpaca (Lamas pacos). Australian Veterinary Journal 82, 711-2, 2004.
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Oregon llamas. Journal of Protozoology 35, 335-6, 1988.
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Eimeridae ) en alpacas, Lamas pacos. Boletin Extraordinario Instituto
Veterinario de Investigaciones Tropicales y de Altura 4, 84-90, 1970.
(18) Palacios CA, Perales RA, Chavera AE, Lopez MT, Braga WU, Moro M. Eimeria
macusaniensis and Eimeria ivitaensis co-infection in fatal cases of diarrhoea
in young alpacas (Lama pacos) in Peru. Veterinary Record 158, 344-5, 2006.
(19) Guerrero CA, Hernandez J, Alva J. Coccidiosis en alpacas. Revista Facultad
Medicina Veterinaria Lima 21, 59-68, 1967.
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infecciosas y parasitarias de las alpacas). Serie de Informacion y
DocumentacionIVATA/CICCS Lima Peru 6, 34, 1967.
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alpacas con Eimeria lamae. Boletin Extraordinario Instituto Veteranario de
Investigaciones Tropicales y de Altura 4, 79-83, 1970.
(22) Foreyt WJ, Lagerquist J. Experimental infections of Eimeria alpacae and
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PB McKenna
Gribbles Veterinary Pathology
PO Box 536
Palmerston North
Email: phil.mckenna@gribbles.co.nz
page

EMAC-Eimeria macusaniensis

This is also a dedication to
Paul Presidente


He was a walking excyclopeadia, heis passion for parasites, saved many farmers their farms, animals, and Australia's top Biosecurity level.
He dedicated his life to the study of parasites, he was my mentor, when I started exporting, he contacted me, and as he heard I was starting out, he said if i needed advice he would be there to assist...and he always was.
ANyone who knows me, i am precise about our worming program.
He worked tirelessly, many times in the middle of the night he would go to work, to do more testings, if ever there was an problem of anything he was there. His research for many years, is now our (and many other farer's ) normal worming methoids, and , management. Others do not know the man who wrote alot of these protocols, or did the research for the methoids to be used.
I was very priviledged to know Paul, and i was shocked when at 56, he was leaving work, and collapsed and died in the carpark of work, early this year.
I was so, so shocked. I miss him, as we would often talk on his fishing trips to Canada, (he was canadian).
Thank you Paul.
But his wealth of knowledge, was unequalled, he did talks all over the world on parasites, and was considered Australia's expert, but he did have a passion for Alpacas, as he was sent over to Nui island about 1994, where a group of approx 600 alpacas were being imported to Australia, and had to spend 12 months there on the island as an Australian Quarantine. Paul, supervised the alpacas and their parasite treatment, and started some of his research.
this is what he says about EMAC.
As an exporter, any alpacas that on go through to Europe, are exported firstly to New Zealand, and have to meet strict parasite protocol, as explained below in the exerpt of discription by Paul Presidente.
In this specilised sugar floatation test everything in the sample is identified, and there has to be ZERO count.
So once the alpacas leave Australia, we are certain, there is no Coccidia in any alpaca from this quarantine farm.
Although now Paul has died, the lab that we have to use for this testing is a NATA accredited lab, and this has to be on the export papers, as well it is like a licence. The lab we use has the licence to do this particular test, only 3 labs are authorised in Australia to do this test.
The labs are also regularaly checked by Animal Health Australia, who oversees the labs, and if they do not meet the standards and the protocol for doing this test, the labs will readily loose the right to do that testing.
I have also dedicated a page to our testing for the NEW Zealand Importing protocol.
http://mariahhillalpacaexport.homestead.com/testing.html please glance at it, there is a lot of detail for anyone who wants to know about importing or exporting alpacas, via New Zealand.
Paul's exerpt explaination on EMAC - Eimeria macusaniensis


Paul Presidente-
a man who I can thank for assisting me to be able to perform as an AQIS Accredited Exporter of Livestock, and to be thorough in my duties.
Eimeria macusaniensis
otherwise known as Emac
Eimeria Macusaniensis ( we will refer to this as Emac )is a type of coccidia seen only in alpacas.There are four types of Eimeria, seen in alpacas.Emac though is rarely seen or identifies itself and even in research very few cases are ever seen.Coccidia is necessary part of life in any species, they have to have a burst of coccidia at one time (and usually around weaning age or lactating females), as then they will throw up antibodies and a life immunity to the disease.Without this the animal will not survive, as coccidia is everywhere and so if an animal is never exposed to a coccidia, they will have no immunity to fight it, because it is impossible that any animal will not be exposed to coccidia at any stage of life.The normal cycle of coccidia is that in times of stress, and I will say the most common forms of stress is transport, lactating females and weanings, a male just maturing and almost ready to work.When the animal is in this stage of life, and in a level of stress, will throw out more oocysts, in their faeces.As once the oocycsts hit air, it takes 48 hours for the oocycsts to sporulate and start multiplying and become able to reproduce. prior to the 48 hrs, they are not in any way contagious.Coccidia is normally also identified when doing random worm tests, but not all the coccidia can be identified under a normal faecal test, purely and simply, if requested, to look for any coccida or all coccida, then the samples are prepared differently for the oocysts to float to the surface.It is usually tested in a suger floatation methoid, but again the best way is to prepare the sugar floatation methoid, that Paul Presidente prepares, as well as it is the one required to meet the NZ protocol.Which is described by Egwang & Slocombe (1982), otherwise, the normal sugar floatation method used in most laboratories only takes 15 mins to prepare the sample, the one we use for quarantine takes 3 hrs to prepare.There are two ways of doing the sugar floatation one by salt and one by sugar.When you do it by salt, you only have it for about 20 minutes, and that is it, it crystallizes and goes to mush and you have lost it after that, but the sugar way it is good for 24 hours, because he gets excited over parasites, and he can pictures etc.He agrees that if you did the floatation with salt, it may not float up, but he always does it with sugar, and he identifies always all the coccidia and identifies the type of Coccidia. He said, Eimeria Macusaniensis (EM) compared to the normal coccidia normal is about 30 millimetre in width where the EM is 100 millimeter in length, and is dark and ugly, and also has four cells inside it). He identifies each species of coccidia, any mite eggs, and of course any worm eggs, and which ones, with the sugar floatation.As explained on the bottom of each lab report sent with the export permit, 3g sub-samples from each alpaca samples submitted were tested according to Parasitology Procedure #PR316. This procedure is adapted from the “Worm Egg Testing Procedure for Export/Import Animals” developed by AgriQuality (now Gribbles) New Zealand. This technique is a highly sensitive test and based on a method for testing cattle faeces described by Egwang & Slocombe (1982).Paul Presidente has told me, that he is the only person in Australia registered to complete this procedure of testing with New Zealand, and had worked hard with New Zealand to adapt the sugar floatation to meet New Zealands standards.He also explained to me many times, that the procedure of even setting up and preparing each sample takes about 3 hours just to prepare.He is very interesting to talk to, and is the main researcher for parasites in Australia, and has completed an extensive study that went over many years, and covering about 200 animals for about 5 years, and following each animal through the whole study.He told me that he has seen in his testing 4 types of coccidia in the animals that have gone to new Zealand, ( over many years), he still identifies each one, and how many, and keeps records of each animal going over. He said that he himself has seen EMAC personally 3 times. The first time on an island in South pacific (Nuie Island) that was used for quarantine for the second shipment of Peruvian Alpacas to Australia.The animal’s faeces were normal, and she was healthy and did not come down with any illness or have any coccidia symptoms.The second time, he saw, I think, he said, a cria from this same shipment, that was being looked after by Dr Ewen McMillan, from Geelong, (regarded as an Australian Alpaca Vet Expert), and this cria, had lost condition, and did have loose faeces, and they treated her with the Sulpha treatment, and that cria went on to live a normal life. He explained to me that the animals are most susceptible to have bouts of coccidia where they throw out the oocycsts, and the most vulnerable time, is a lactating mother, a cria, and of course a cria being weaned. He has done studies of this on sheep, and is conducting studies all the time.In his time he has tested over 1500 alpacas to go to New Zealand. He said that firstly, when something or other coccidia are identified, (other tha those being exported) he then checks to make sure the animal is healthy, and the faeces is pelleted. and in their experience if the alpaca is in a healthy state and the faeces is pelleted, there seems to be no problem with the animal, the animal is healthy, and shows no sign of loosing condition it appears not life threatening. Then he notes it, and it goes no further, but before this he checks up with the covering veterinarian to make sure that the animals is performing normal, and they are asked to keep noting the said animal. He said this is sometimes a normal life cycle an animal will go through, and then they will throw up immunity to this
If it is found in an export shipment, the alpaca would be rejected from being exported.
The times that they are likely to get a bout of it, is when they female is lactating, they generally will throw up a few of these oocycsts, and then the cria will often pick it up from the mother, and everything will be alright, other than when you start weaning it, and then the weanling under stress from the weaning process will then throw up some oocycsts then they will have a bout of it, until it's immune system kicks in and they develop an immunity of it., and this goes on and on.Once an animal that has coccidia oocysts, has expelled faeces, 48 hours later the oocysts will sporulate, and it will take about 13 days later before any significant signs of coccidiosis is seen.The only form of transmission, is for contact with the sporulated species.This is completely the only way.It cannot be transmitted between animals mating, as is claimed by one person in NZ.In normal farming husbandry, if a group of animals are shedded, in close quarters for a few days, and the bedding is not completely removed (I mean completely), on a daily basis, and then not disinfected, then this will encourage contamination.The simple reason also, is the stress of being shedded or housed in a situation, will make any animal that picks up the sporulated oocysts more susceptible, purely the stress of housing.In our quarantine facilityWe clean all faeces off the mats that the animals are housed on twice daily, first thing in the morning, and then in the afternoon. The animals are house on compressed gravel, but on top is a meshed mat, so all urine will run through to the gravel, and the faeces is on top. We pick up all the faeces.We also then pressure clean any of the main areas that the dung has been on, and then the whole area, not just the dung areas, is then sprayed with a chlorine solution (to Paul’s directions), and alternately, (disinfected and nucidole (ectoparasite treatment), on a rotating daily routine).As once the oocycsts hit air, it takes 48 hours for the oocycsts to start multiplying and become able to reproduce. prior to the 48 hrs, they are not in any way contagious.But all faeces have been removed well before this stage, and moved off the whole facility, and also any bacteria etc would be killed through the chlorine solution.Paul Presidente, and MAF agree- it is most unlikely that any cross contamination can occur in our quarantine facility, because of our cleaning methods.As our Parasitologist is a world expert, and had completed research and knew of others who had also researched parasites in alpacas, over studies taking over quite a few years, and was willing to share his knowledge.
In read on a recent Private breeders newsletter, (and obviously this breeder does not know a lot about coccidia and Emac and a lot of assumptions were made), the animal when it expels the oocysts, it is random, and it does not shed for 30 days.For example on the research completed in Australia, each time the researchers took samples, was 20 times on each animal over a 3 day period, as they can shed here and there, and not constantly and not for a 30 day period.By taking 20 samples, they can assess it properly, as they may take a sample today with no oocysts, but tomorrow there may be 5, and the next day none.I think you may notice that I have not mentioned Emac specifically without mentioning coccidia, as all the coccidia is treatable, and unless poor farm management will not cause any problems.For example, I was speaking to some breeders who used to breed goats, and chickens, and they can tell you or any goat and chicken breeder can tell you, if you have poor cleaning methods in sheds that house a lot of animals, you will without a doubt, get coccidia.It is also safe to mention that it will not cause or get ever to an epidemic.
Emac is about 3 tims larger and heavier than the normal coccidia, and so a normal sugar floatation test will not reveal it.
Because it is heavier, they need longer to float up, that is why they leave it for 3 hours, to get all eggs and oocysts to the top.

I would like to point out again- no alpaca from Australia has EMAC -they have been thoroughly checked and cleared of any endoparasites.
As quoted from New Zealand Biosecurity- http://www.biosecurity.govt.nz/publications/surveillance/2006
Oocysts of this coccidian species, which
are readily recognisable by their dark brown colour and pyriform
shape, measure 81-100 μm long by 60-80 μm wide. They also have
thick oocyst walls (approximately 8-12 μm thick) and an obvious
micropylar cap (Figure 1). Eimeria macusaniensis is considered by
some to be highly pathogenic in alpacas(4). However, although this
coccidian may have the potential to cause death and disease in both
young and adult camelids, the regularity with which it is likely to do
so may have been somewhat overstated.

Treatment
I read on alpaca nation an experience, as printed here,
http://www.alpacanation.com/forum/topic.asp?whichpage=-1&TOPIC_ID=3237
She was in with a group of females at various early stages of pregnancy so the farm owner wisely contacted Dr. Toni Cotton, who specializes in camelid reproductive issues. Her reply was that Corid and Albon have variable effects on EMac and are not as consistant as Ponazuril in successfull treatment. Ponazuril is the ONLY known effective treatment for EMac. EMac can encyst in the intestinal tract and cause chronic protein loosing enteropathis, weight loss and ill thrift, usually the only signs you see. There is no egg shedding when this happens and that is one of the reasons it is hard to detect. Also, there is none of the telltele diarrhea that is seen with the other coccidias. Beacuse the effects of Ponazuril on the developing fetus is unknown, it was recommended that this group of females be kept together until all were at least 90 days out on their pregnancies and then treat THE ENTIRE GROUP for 3 days with Ponazuril and retest in 2 weeks. All the previously positive animals were then testing negative, as they did again in another 2 weeks. The reason it seems to be 'harder to treat' as you stated, is that many falsely believe they can treat with Albon or Corid. Treatment with Ponazuril has been 100% effective in the cases I have known of personally. "as quoted from topic.

I have heard that baycox is also a good treatment, and pre caution, if animals are going to be understress and mixed with other animals from different farms, dosage.
Baycox - dose rate is 20mg/Kg. Best regime is give this dose on two consecutive days, then repeat in 10 days.