Cryptosporidiosis in Angora GoatsTuesday, 8th June 2021
By Dr Mackie Hobson
CRYPTOSPORIDIOSIS IN ANGORA GOATS
Cryptosporidiosis referred to as ‘Crypto’ has been a major problem in calves and lambs under intensive conditions in South Africa since 2013 and has now affected the first Angora goat farms.
The first cases of Cryptosporidiosis in Angora goat kids were recorded in Australia in 1981.
Prior to 1980 cryptosporidiosis was considered rare throughout the world and was first reported to cause diarrhoea in cattle in 1971 and the first cases in humans in 1976. The disease has progressed to a major problem internationally and developed to a point where 38% of the reported neonatal calf scours in the UK is due to Cryptosporidiosis.
Cryptosporidium parvum, a protozoa which is about a 10th of the size of a Coccidia oocyte, causes diarrhoea in young and immunocompromised animals and is usually associated with explosive outbreaks.
It can be transmitted from man to animals (Zooanthroponosis) as well as from animals to man (Zoonosis). The initial outbreaks in South Africa were likely from human sewerage effluent entering our river and water systems and ending up on irrigated pastures or in livestock drinking water.
In South Africa, the initial explosive outbreaks resulted in losses of 10-50% of lambs on affected farms in the Eastern Free State. During the following years, the outbreaks tended to occur more during the tail end of lambing as immunity built up and the transfer of antibodies occurred through the colostrum. However explosive outbreaks have recurred a few years after the initial outbreak on some farms.
What age of kids are affected?
Infection usually occurs in kids 1-4 weeks old (5-14 days but up to 3 months). Outbreaks are likely to be seen in intensive conditions such as lambing pens, ’kraaling’ at night, irrigated pastures and kidding in small camps.
How can Angora kids be infected?
The infection is via contaminated food or water or directly between shedding individuals via the faecal-oral route. The oocytes shed in the faeces are very resistant in the environment and may survive for a year/s. They can survive temperatures ranging from -20 to 60°C . These oocytes can spread via subclinical carriers, waterways, fomites, wildlife, flies, mechanical vectors and humans.
The movement of subclinical carriers (goats and sheep) between farms is of concern within the mohair industry. These carriers may introduce oocytes which can then be picked up by the kids/lambs during the following kidding season and result in an outbreak, as has already occurred in the Graaff-Reinet district as the result of introduced sheep ewes.
As few as 10 oocytes can cause disease in calves and 1 oocyst in lambs/kids. Billions of oocytes can potentially be shed by an acutely infected kid (>100 000 per gram faeces).
The life cycle of Crypto
Oocytes are taken in orally and contain 4 sporozoites which are released after ingestion. These sporozoites invade the cells of the intestine going through several life stages to ultimately produce oocytes. These oocytes are thick and thin-walled. The thin wall oocytes rupture resulting in autoinfection. The thick-walled oocytes pass out through the faeces to contaminate the environment.
The life cycle is rapid and can be as short as 3-4 days.
Crypto lives for about 5 weeks in the intestine and can survive for years in the environment as thick-walled oocytes.
What happens to the intestinal wall after infection?
The infection leads to cell destruction of the intestinal wall resulting in atrophy and fusion of intestinal villi (the finger-like projections from the intestinal wall responsible for nutrient absorption). The destruction of cells leaves them vulnerable to invasion by intestinal bacteria and viruses.
The incubation period is 2-7 days but can be as long as 10 days. Clinical signs usually lasts 2 weeks and animals can relapse a week or two after recovery. Recovery may take up to 30 days.
Kids in the first two weeks of life are most affected but up to 3 months can show clinical signs. Older kids are often asymptomatic.
- Except when occurring in very young kids the infection is not detected or causes mild diarrhoea.
- The rectal temperature usually 40 °C
- Reduced appetite, lethargy at the start, followed by diarrhoea
- A profuse yellow, white or grey diarrhoea with mucous can occur in kids. Kids will be anorexic and depressed.
- Loss of body weight
- The kid may strain to defecate and show abdominal pain.
- Stiffness, hyperpnoea (rapid breathing), slow gait and depression
- Dehydration and death may follow.
The symptoms in those that survive usually lasts 7-15 days.
What is seen on a Post Mortem examination?
- Dehydrated young kids
- Intestine gas-filled and contains yellow watery fluid
- Lesions are found in the ileum, caecum and colon.
- Inflamed intestines
Diagnosis: Post Mortem Tests and Sampling.
A presumptive diagnosis can be made on history and clinical signs as well as a positive ‘Rapid Test’ but a definitive diagnosis must be made by:
- Histopathology: 2 sample pieces of the duodenum, jejenum, and proximal colon should be taken placed in 10% formalin and sent to the laboratory.
- A culture sample helps to determine if other pathogens are present (E, Coli, Salmonella or Clostridia). Important in calves for Rota, Salmonella, E.Coli.
- Rapid Test Antigen swabs are taken from the ileo-caecal junction. This allows a quick on-site presumptive diagnosis. Take the sample from the ileum side of the junction. The Rapid Tests (Antigen detection) include:
- Zoetis WITNESS Bovid-5 Test
- Afrivet Rapid Test kit Bovid-5 (below left)
- Pet-X Rapid Test kit (Below right)
- Modified Ziehl-Neelsen (mZN) Microscopic staining of faecal samples. Faecal samples are sent ‘cold chain’ to the laboratory.
THE RAPID Antigen Tests as a SCREENING TEST on rectal or faecal samples from suspected SUBCLINICAL CARRIERS IS NOT EFFECTIVE.
Collection and storage of samples:
Faecal samples for Cryptosporidium should be tested as soon as possible. Alternatively, samples can be frozen or preserved with 10% formalin if testing can only be done at a later date, however, if PCR-based techniques are to be used, formalin can reduce the sensitivity of PCR. Freezing also not advised if PCR is to be done (Vetdiagnostix)
Since the shedding of cysts may be sporadic, at least three consecutive samples should be collected or possible taking a pooled sample from 5 + individuals to account for sporadic shedding. Take rectal faecal samples - not from the floor.
How can Crypto be prevented from occurring on a farm- BIOSECURITY?
Ideally, the farmer does not want to be faced with the problem of Cryptosporidiosis so BIOSECURITY of the farm is critical.
Ensure you have an owner’s declaration signed by the owner’s vet or agent that cryptosporidiosis has not been diagnosed on the farm when purchasing goats.
Livestock bought via a livestock agent has specific biosecurity protocols as stipulated in the STAATSKOERANT, 13 NOVEMBER 2020 No. 43900 205, 135 Agricultural Produce Agents Act (12/1992): Biosecurity Rules for Livestock Agents 43900.
- Providing a vendor health declaration is the law.
The protocol on your farm must not only be for animals being introduced but include vehicles and people entering your farm. You don’t want visitors parking near your animal handling facilities or in areas where your stock may graze!
As cryptosporidiosis can be carried by adult goats the producer may only see the first signs of crypto when kidding the following year- so after quarantine still keep introduced goats on their own away from your breeding flock if possible and be aware of your water drainage systems.
No biosecurity protocol is foolproof but it is about reducing your risk.
Buy your goats from farms you know and can trust that is also adapted to your environment and production system type.
WHAT TO DO IN AN OUTBREAK?
Make sure you have a positive diagnosis from your vet
- Biosecurity Protocols
a. Isolate and quarantine sick kids with their ewes (move the healthy ewes/kids out of the camp/pen and leave the sick in)
b. Move the healthy ewes out of the infected camp - use a footbath with Chlorine dioxide (see below disinfectant section)
c. Ensure the healthy ewes and kids are divided into the smallest groups that you can. This will limit the number of infections as much as possible. (1 infecting 25 or 50 rather than 500)
d. Keep the last 20% of ewes to kid in a separate camp as contamination of the environment tends to build up from the older shedding kids.
e. Watch out for mechanical transmission (clothing, people, dogs, vehicle and equipment movement).
f. Check drainage areas from contaminated areas
g. Avoid moist areas, leaking troughs.
h. Make sure feed and water troughs are at a height where faecal contamination can not occur.
The following treatments have been shown to be of benefit in treating Crypto.
Remember it is a zoonosis (humans can get it) so use PPE and hygiene protocols
a. Halocur (Halofuginate)
The ONLY CURRENT TREATMENT for Crypto in SA. Halocur treats the free stages not intracellular stages.
OFF LABEL USE - A special order application must be completed by your vet.
- 1ml per 5kg daily for 7 days orally (10 days has been advised by the manufacturer for goat kids) to break the life cycle. Start 48 hrs after birth (Calves start 24 hrs after birth)
- Halocur must not be given on empty stomach (Toxic levels). Oral administration after giving electrolytes
- WEIGH the Kids, mark their weights by marking it on the body for f/up treatments.
- Use a 1 ml syringe for an accurate dose. Halocur has a narrow safety margin.
- Clinical signs improve 24-48 hrs after the start of treatment
- If implemented prior to clinical signs developing there are farmers who treat all the lambs for 3 days from day 2 and then only treat those lambs with clinical signs for a further 4 days (7 days in total) -with good response.
- Halocur reduces oocyte count and allows immunity to develop
b. Electrolyte mixtures
Ensure sick kids are rehydrated. Administer 100 ml of an electrolyte mixture up to 3 times a day if possible (The equivalent of 10-20% of body mass a day).
Administer electrolytes prior to the Halocur treatment
Examples of electrolytes:
c. Mineral Vitamin supplements
- Vit E, Selenium: Inject on day 2 after birth (There are a number of products available https://www.angoras.co.za/article/mineral-and-vitamin-options
- Immunovite (MSD)
Use 0.75 - 1 ml undiluted product per kg body mass for optimum support.
Bacillus amyloliquefaciens acts as a probiotic with fulvic acid to provide functioning support to the gastrointestinal tract with healing properties. It contains vitamins and certain trace elements (It does not contain Selenium or Vitamin E)
d.Treat the Pain/Inflammation:
Most kids will have a fever (>40C) and have abdominal pain.
Inject 0.25ml/10kg Meloxicam (20mg/ml) under the skin -The effect lasts for 3 days
- EM1 (Effective Microbes) kids 2 ml after birth, can add to water 1:1000 daily
EM Technology application (MZP) was developed in Japan
Applied as pro-biotic, feed additive.
It improves the gut microflora
- Immunovite (as per Mineral Vitamin above in section c)
- Other probiotics examples include Protexin, Biorem.
f. Deccox (Decoquinate) Zoeitis
This is added to the ewes feed from 4 weeks before kidding and as a creep feed to the kids (This reduces the impact of crypto and is effective in controlling coccidiosis).
See point 4. In the section below ‘How can I reduce the impact before ewes start kidding on a Crypto positive farm?’
If indicated (secondary infections in those with clinical signs).
Other treatments include:
- Parofor Crypto (Huvepharma)
LISCENCED FOR GOATS but not yet available in South Africa. May be registered soon.
Parofor Crypto contains Paromomycin(140mg/ml) is a broad-spectrum antibiotic and belongs to the group of aminoglycosides.
Dosage: Oral: 0.25ml/kg bodyweight for 7 days (2.5ml/10kg for 7 days)
Reduces oocyte counts and reduces the severity of diarrhoea.
It is also licenced to treat Enteric Colibacillosis in calves. In trials, 33 positive lambs tested negative (ICT tests) after treatment with Parofor for 5 days
- Nekka-Rich (Four Lakes)
This is activated charcoal and wood vinegar and has shown efficacy in reducing or eliminating Cryptosporidium parvum in calves.
Prevention Dose: 5g per kid or lamb (20g for calf) twice a day for 10 days
Treatment Dose: 5g per kid (20g for calf) twice a day for 4 days.
Also, give electrolytes at the same time of treatment.
- It has also been reported that Activated charcoal (Dosed or tubed at 2g/kg body weight) and Garlic is beneficial.
What can be done to reduce the impact of Crypto BEFORE the ewes start kidding on a Crypto positive farm?
- Add ‘Deccox’(Decoquinate) Zoeitis to feed of ewes 4 weeks before kidding and continue to 2+ week after kidding.
Deccox is not licenced for crypto but it has been demonstrated in trials that if ewes/cows are given Decoquinate in feed 4 weeks before and 1 week after kidding at 1.25mg/kg a day it prevented the appearance of crypto.
This was also shown in cows (4 weeks before to 1 week after calving) at 1.25mg/kg prevented crypto (Havant, Cantaloube) over a 7 year trial period.
This finding was repeated in trials by Bremmer and Richard in Scotland with the same results.
Infected kids treated at 2.5mg/kg reduced the severity of the crypto and reduced shedding. This was also demonstrated in the reduction in calves when treated from day 3 to 17.
However, Lallemand et al 2006, Moore et al 2003 said Decoquinate was ineffective against crypto.
- Vaccinate the ewes 4-6 weeks before kidding (Multi-clostridium Vaccine)
Antibodies are carried over in colostrum
- Give Mineral and Vitamin supplements 4-6 weeks before kidding
Carried over in colostrum to the kid.
See options on website https://www.angoras.co.za/article/mineral-and-vitamin-options#360
- Ensure good nutrition for 4 weeks before kidding and 2 weeks into kidding
This ensures good and plentiful colostrum production. With added Deccox!
- Separate the pregnant ewes into the smallest groups possible. This reduces the risk when kidding as 1 sick kid infects 50 instead of 500 (or less if possible).
- Keep the ewes that will kid last separate from earlier kidding ewes. This reduces the build-up of oocytes in the environment to infect the late-born kids.
There is no vaccination. The manufacturer of a vaccine in Europe was attempted but was ineffective.
What can be done to reduce Crypto in the environment?
Disinfect kidding areas and equipment with one of the following. Treatment of water sources.
a. Chlorine dioxide
Chlorine dioxide can inactivate cryptosporidium oocytes. (5mg/l) (50ppm)
50ppm safe both as a disinfectant to treat the environment and in drinking water. *
50ppm 1-2 minutes contact time **
- Nanotech SA makes a powder (3kg) that makes 440 litres of 3000ppm which can then dilute to 150ppm to treat the environment.
- AQUAVi2000-500 Chlorine dioxide industrial and agriculture application
Stock preparation 19.2-litre water, add 400ml Precursor A, mix, then add 400ml precursor B, mix and stand 30 min.
For animal housing 150ppm use stock made (2000ppm): take 75ml stock and dilute with 925ml water to make 1 litre
- OxyFect® 8504, a surface disinfectant that kills Crypto.
Add 1 tablet to 10 Litres of water to instantly create a Zero-Residue disinfectant which is so safe you can use it as a mouthwash
- OxyAzur® 8205 Add 1 tablet to 1500 – 2500 Litres of water in a water tank to eliminate unwanted microbes and heavy metals, safe to drink within 30 minutes*
- Some other Chlorine Dioxide disinfectant products include:
Duo Chlorine Dioxide Detergent-disinfectant - Tristel
Biox 5000 Chlorine Dioxide Disinfectant - Xie Import & Export
Xzioxa Mix Chlorine Dioxide Disinfectant - Taiaha SA KZN
Dutrion Chlorine Dioxide Disinfectant - Green Technologies SA
Calgonit CD-K System Chlorine Dioxide Disinfectant - ImproChem GP
Surface Gene Chlorine Dioxide Disinfectant - Process Catalysts CC GP
Vital Oxide Chlorine Dioxide Disinfectant - Protectapak CC GP
Aqquon 20 Chlorine Dioxide Disinfectant - WR Petroleum Logistics KZN
Xziox Mixed Chlorine Dioxide Disinfectant - Mpumamanzi Group
Dutrion Chlorine Dioxide Disinfectant
Vital Oxide Chlorine Dioxide Disinfectant
Effective against Cryptosporidium. Spray a 2% solution, rinse feeding and drinking troughs. For Crypto dilute 1:50 (contact time 2 hours)
4% (1:25) also eliminates Coccidiosis
Neopredisan 135-1 (Bupo Animal Health)
Proved effective against crypto at 3% for 1 hr (Mix 30ml to litre water)
Neopredisan is also effective against coccidiosis.
d. Hydrogen peroxide
3% solution inactivates Cryptosporidium in 40 minutes and eradicates in 30 minutes
Don’t use water containing Chlorine (municipal water) as antagonists.
- Afrisan Peroxsil Ag+
- 10% Ox-Virin
e. 10% Formalin (irritates mucous membranes of nasal passages and eyes)
2 hours later overwhelm the area with good bacteria
Expanded EM) 1:50 if using small ‘lambing pens’. Not practical in larger areas.
EM Technolgy application (MZP), Developed in Japan. EMViro Environmental application for Pens/barns 1:50 daily for a week then 1:200 weekly. Dams/effluent ponds: 1:1000 by dam volume then 1:5000 by dam volume
- Boiling, steam, pasteurisation and industrial UV light are also effective in killing crypto
- Bleach, chlorine, alcohols, phenols, Quaternary Ammonium products and iodine are NOT effective.
Ploughing up land contaminated with crypto may bury the oocytes and reduce oral intake.
During an outbreak attempt frequent removal of faeces if possible.
SCREENING of HEALTHY (carrier) animals for BIOSECURITY reasons
Are the number of Oocytes being shed in a healthy carrier sufficient to be detected on testing?
Cryptosporidium positive animals are known to shed oocytes intermittently so may test negative although still a carrier. By testing a number of individuals from a flock it would be hoped that this would overcome the problem of detecting intermittent shedders to screen a flock or farm for the presence of carrier animals.
To check the viability of these tests Mohair SA/SAMGA conducted 2 field studies?
a. Clocolan - Eastern Free State
Testing with Dr Liezel Wasserman (Clocolan Veterinary Clinic) where we tested 13 healthy sheep on a Crypto positive farm that was currently having lamb deaths.
3 Groups were tested:
- (a) 5 rams that had been on the farm for over a year.
- (b) 3 rams that had been introduced 3 months prior to which were present during the current outbreak
- (c) 5 Ewes that had lost lambs due to Crypto
(1): BoviD-5 Ag Test Kit -Rapid Test Kit (Afrivets) ALL groups tested NEGATIVE
(2) PCR (Vetdiagnostix): ALL groups tested NEGATIVE
(3) Microscopic staining - Modified Ziehl-Neelsen (mZN) (Western Cape Labs Dr J. Stroebel): 7/13 tested POSITIVE
b.Graaff-Reinet - Eastern Cape.
The farm had lambs currently infected by Crypto which was confirmed positive on histopathology and rapid test results.
5 healthy ewes that had lost lambs due to Crypto were tested.
(1): PetX Rapid Test Kit ALL ewes tested NEGATIVE (A lamb with clinical signs tested positive)
(2) PCR (Vetdiagnostix): ALL tested Negative
(3) Microscopic staining- Modified Ziehl-Neelsen (mZN) (Western Cape Lab- Dr J, Stroebel): 1/5 tested POSITIVE
These results suggest that testing for sub-clinical carriers as a Biosecurity measure to screen a flock by Microscopic staining would be beneficial. Able to detect low numbers of Oocytes (on average less than 1 per 400x field)
The results suggest that the PCR probe is not sensitive enough to detect the healthy carriers of crypto.
The emphasis will be on individual producers/farms to prevent Crypto from occurring by:
Maintain a strict BIOSECURITY POLICY
- Purchase livestock from farmers who Producers know and can trust.
- Producers must request an owner’s declaration signed by the owner’s vet stating that cryptosporidiosis has not been diagnosed on the farm when purchasing goats.
- Purchased goats should be placed in quarantine and faecal samples obtained (from approx. 10 goats) for microscopic screening.
- If ewes are purchased run them as separate flock after quarantine until after the first kidding
INFORMATION OF INTEREST:
The development of immunity
Cryptosporidiosis in ruminants is a neonatal disease and adults are seldom affected. This suggests immunity plays a major role in reducing the impact of the disease. Both acquired immunity and host age determine the susceptibility to and severity of infection.
The following years after an outbreak the transfer of antibodies in the colostrum is important and reduces the impact of Crypto with usually only the tail end of kidding/lambing a problem due to the increased environmental challenge.
No successful vaccine has been developed.
What is the incidence of Cryptosporidium in wildlife?
Surveys in the Kruger National Park tested 445 samples.
Elephant (25.8%), buffalo (5.5%) and impala (4.3%) tested positive. There were significantly more positives from animals adjacent to western boundary (human, domestic animal transmission).
Cryptosporidium in humans
What are the symptoms in humans? The diarrhoea is profuse and watery; it may contain mucus, but rarely blood. It is often associated with weight loss. Other less common clinical features include abdominal pain, nausea and vomiting, and a low-grade fever
Human outbreaks and prevalence:
- 1987, cryptosporidiosis was associated with 13,000 cases of gastroenteritis in Georgia
- In 1988 and 1989, two Cryptosporidium-related waterborne outbreaks were reported in Ayshire, Scotland, and Oxfordshire-Swindon,
- Cryptosporidiosis was reported in 1993 in Milwaukee, Wisconsin, USA where an estimated 403,000 people were infected due to faulty filtration of the water.
- Prevalence rates in Europe reported being 1 to 2%. North America prevalence of 0.6 to 4.3% is lower than those reported in surveys from Asia, Australia, Africa, and Central and South America which ranged from 3 to 20%.
- Prevalence was highest in children less than 2 years of age, and infections were often seasonal, with a higher prevalence during warmer, wetter months.
- Sero-prevalence rates in Europe and North America are usually between 25- 35% compared to 64% in South America.
The different tests for cryptosporidiosis
1. Direct microscopic examination
As the cysts of Cryptosporidium are tiny, a staining procedure is required to identify them. Conventional methods of stool examination (ie, routine "stool for ova and parasites" testing) are unreliable.
A number of different staining techniques have been developed.
- Ziehl-Neelsen (ZN) is an Acid-fast procedure -staining is a bacteriological stain used to identify acid-fast organisms. Acid Fast positive cells are stained pink/red and Acid Fast negative cells are stained the light blue colour of methylene blue.
Modified Ziehl-Neelsen (mZN) -with this method, the dyeing time is shortened and heating is not required.
- Auramine Phenol (AP) The parasites appear greenish-yellow against a dark background. The method is more rapid and sensitive than ZN technique.
- Immunoflourescence Microscopy (IFM) is a widely used example of immunostaining and is a form of immunohistochemistry. Specific antibodies bind to the protein of interest. Fluorescent dyes are coupled to these immune complexes in order to visualize the protein of interest using microscopy. IF microscopy can be used in several microscope designs for the analysis of immunofluorescence samples.
Detect soluble protozoan antigens in faecal samples, thus removing the need for microscopic examination.
- Enzyme immunoassay (EIA) and enzyme-linked immunosorbent assay (ELISA) technologies have been used to develop commercial products for the detection of Cryptosporidium
EIA, ELISA has the advantage of good specificity, and a large number of samples can be processed in a short time.
- Immunochromatographic lateral-flow (IC) or (ICLF) 'dipstick' tests have also been developed for antigen detection in stool samples. These tests are sensitive and specific, easy to use and provide a result in 10 minutes.
Immunochromatography is a test format that uses tagged particles as a colour signal rather than an enzyme-catalyzed colour change reaction as in ELISA. The test uses biologics and tagged microparticles coated with specific Crypto antibodies.
These ICLF tests are the Rapid tests used in the field.
3. Molecular biology
PCR or real-time PCR (RT-PCR) is a molecular biology-based diagnostic detection method developed to target specific sequences in the protozoan genome. These methods offer highly specific and sensitive assays but are expensive and time-consuming.
- PCR is the GOLD STANDARD test- are more sensitive with the detection range from 1 to 106oocysts, are relatively rapid, and have the major advantage of speciation which is very important from an epidemiological point. This comes with costs and time disadvantages.
Comparing the SENSITIVITY and SPECIFICITY of the different Tests
What is sensitivity and specificity?
Sensitivity is the ability of a test to correctly identify the animals with crypto (True Positive).
Specificity is the ability of a test to correctly identify animals without crypto (True negative).
PCR is considered the gold standard to test for the presence of Cryptosporidium.
COMPARING the different tests in the table below:
HOWEVER, these sensitivity and specificity are tests on samples from cases showing clinical signs.
The ability of these tests to pick up SUBCLINICAL CARRIERS (ie. goats that are not showing any clinical signs but are shedding low numbers of Cryptosporidium oocytes)?
Microscopic staining techniques, mZN (Dr Jacob Stroebel-Western Cape laboratory) were able to detect carriers with on average less than 1 per 400X field. PCR (Vetdiagnostix) and ICLF tests were not able to detect healthy carriers.
Dr Mackie Hobson, BSc (Agric) BVSc
Mohair SA, SAMGA Veterinarian
With special thanks to Dr Liezel Wasserman from the Clocolan Veterinary Clinic for sharing her expertise and experience working with Cryptosporidiosis
- Dr Liezel Wasserman (Clocolan Veterinary Clinic)
- Dr James Hill (Vetdiagnostix)
- Dr Jacob Stroebel (Western Cape Laboratories)
- *Efficacy and Safety Evaluation of a Chlorine Dioxide Solution by Jui-Wen Ma 1,2,Bin-Syuan Huang Chu-Wei Hsu ,Chun-Wei Peng ,Ming-Long Cheng ,Jung-Yie Kao ,Tzong-Der Way ,Hao-Chang Yin and Shan-Shue Wang
- ** Bovine veterinarian Jan 2015 John Maday
- Efficacy of Two Peroxygen-Based Disinfectants for Inactivation of Cryptosporidium parvum Oocysts. Joaquin Quilez,* Caridad Sanchez-Acedo, Catalina Avendan˜o, Emilio del Cacho,and Fernando Lopez-Bernad
- Dr Marijke Henton
- The prevelance of Cryptosporidium in wild animals in the Kruger National Park. Nada Abu Samra, Ferran Jori, Amidou Samie, Peter Thompsom
- Aust Vet J. 1981 Aug 57(8):386-8.Intestinal cryptosporidiosis in a kid goat.
- Genetic Characterisation of Cryptosporidium spp in diarrhoeic Children from four provinces in South Africa, Abu Samra, P. Thompson, F,Jori, J Frean, B.Poonsamy, D du Plessis, B Mogoye,L. Xiao
- Mason RW, Hartley WJ, Tilt L.
- MSD Veterinary manual
- Infectious Diseases of Livestock Coetzer, Thomson, Tustin
- Aust Vet J. 1981 Aug;57(8):386-8. Intestinal cryptosporidiosis in a kid goat. Mason RW, Hartley WJ).
- Cryptosporidiosis WILLIAM L. CURRENT' AND LYNNE S. GARCIA
- Cryptosporidiosis control in ruminats: Franck Foulon,
- Veterinary Investigation Surveillance Report (VIDA, 2012))
- Cryptosporidiosis in Cattle,The Moredun Foundation,Beth Wells BSc, PhD,Sarah Thomson
- Laboratory diagnosis of cryptosporidiosis Sumeeta Khurana and Preeti Chaudhary
- Cryptosporidium/Giardia Detection and Identification Methods in Water Treatment, Clinical, and Food Applications, Rapid Microbiology
- *2 Comparison of PCR and Microscopy for Detection of Cryptosporidium parvum in Human Fecal Specimens: Clinical Trial U. M. MORGAN, L. PALLANT,B. W. DWYER,D. A. FORBES, G. RICH, AND R. C. A. THOMPSON
- The Prevalence of Cryptosporidium Infection in Neonatal Diarrhoeic She ep Lambs with Observation of Resolution using Paromomycin. Osman A Hameed,Taj Elsir SA Abu-Zeid,Ghulam Rasool,Albadri Makki,Mohamed Khidr Taha and Brigitte Duquesne
- *1 Comparison of diagnostic sensitivity and specificity of seven Cryptosporidium assays used in the UK Free Rachel M. Chalmers, Brian M. Campbell, Nigel Crouch, André Charlett, Angharad P. Davies,
- *3 Zoetis- Veterinary Diagnostic Laboratory, University of Minnesota, St. Paul, Minnesota.
- *4 BioNote Clinical Evaluation: Anigen Rapid Rota Ag Test Kit Diagnostic,Sensitivity and Specificity, Zoetis LLC.
- Feeding Activated Charcoal from Bark Containing Wood Vinegar Liquid (Nekka-Rich) Is Effective as Treatment for Cryptosporidiosis in Calves S. Watarai,*1 Tana,† and M. Koiwa‡
- Fritz Rexrodt SWAVET RSA PTY Ltd- Afrisan