Calf diarrhoea as a complex is caused by a number of different micro organisms including viruses, bacteria, and protozoa. Classification of different aetiological causes is best done by determining the age of the calf when the diarrhoea begins.
Week one of age:
E.coli
E.coli infections also known as Colibacillosis or calf scours is a bacterial infection resulting in moderate to severe yellow pasty diarrhoea in one week old calves. The onset of dehydration and death occurs rapidly in such cases.
Diagnosis: A tentative diagnosis is often made from presenting clinical signs as well as the macroscopic appearance of the faeces as well as the age of the calf (yellow/grey colour). A definitive diagnosis is made on bacterial culture.
Treatment: Symptomatic treatment to maintain the calf’s hydration status is recommended. The use of antibiotics is warranted in these cases. Antimicrobial resistance is becoming an ever-growing problem, meaning our antibiotics need to be reserved as much as possible. Antibiotics in the Sulphonamide group (Maxisulf, Norotrim and Sulfatrim) as well as the Flouroquinolone group (Baytril) are often effective against E. coli infections.
However, it is always recommended to submit faecal samples to a registered laboratory for bacterial culture and antibiogram. The antibiogram will tell us which antibiotics work effectively against E. coli.
*It is important to note that Baytril is not a first line antimicrobial and must always be used sparingly.
Prevention: Prevention is always better than cure! Vaccination of Heifers (8 weeks and then 4 weeks prior to calving) as well as Cows (4 weeks prior to calving) with any registered vaccine against E. coli. This will ensure there are sufficient levels of maternal antibodies when the calf drinks colostrum.
Biosecurity: Isolate the affected calf and then so to prevent spread to the other calves. Regular cleaning with a registered disinfectant is recommended.
Rota and Corona Virus
Diarrhoea caused by Rota and/or Corona virus commonly affects calves within the first week of life. Clinical signs include mild to moderate diarrhoea, dehydration, and a reduced appetite. Calf Diarrhoea as a result of these viruses are associated with low mortalities.
Diagnosis: Diagnosis is done through viral isolation from a faecal sample at an accredited laboratory.
Treatment: Symptomatic treatment is recommended. Electrolytes (Replensol/Electrogaurd). Antibiotic use is not advised in these cases.
Biosecurity: Isolate the affected calf so to prevent spread to the other calves. Regular cleaning with a registered disinfectant is recommended.
Week two of age:
Cryptosporidium parvum
Diarrhoea caused by the protozoal organism normally occurs around two weeks of age. On visual examination, the diarrhoea appears grey and pasty and is associated with an extremely high mortality rate. Once Cryptosporidium parvum is present on a farm, eradication of the organism is difficult due to the organism’s persistence in the environment as well as the protozoa being able to replicate within the host itself resulting in autoinfection.
Disinfection: Disinfection and eradication of the organism has proven extremely difficult. Disinfection of calf crates/pens with bleach and boiling water has found some success.
Diagnosis: Faecal sample submission to a registered laboratory will confirm infection. Rapid test kits will be available soon to diagnose on the farm.
Treatment: Electrolytes (Replensol/Electrogaurd). Halocur® or Parafor® are the recommended drugs for the treatment of Cryptosporidium.
Prevention: No vaccine is currently available against Cryptosporidium. Biosecurity and maintaining good calf crate/pen hygiene is of the utmost importance in preventing disease outbreaks.
It is important to note than Cryptosporidium is a zoonotic disease.
Week three of age:
Salmonellosis
Calf diarrhoea caused by Salmonella spp. (Typhimurium and Dublin) commonly affects calves three weeks and older. The diarrhoea has a characteristic yellow colour with fresh blood and necrotic material present. The diarrhoea also has a really bad smell to it.
Diagnosis: A tentative diagnosis is often made from presenting clinical signs, the macroscopic appearance of the faeces as well as the age of the calf (yellow with blood and necrotic material present. A definitive diagnosis is made on bacterial culture.
Treatment: Symptomatic treatment to maintain the calf’s hydration status is recommended with electrolytes. The use of antibiotics is warranted in these cases. Antibiotics in the Sulphonamide group (Maxisulf, Norotrim and Sulfatrim) as well as the Flouroquinolone group (Baytril) are often effective against Salmonella infections. Some success has been seen with the Florfenicol group of antibiotics (Nuflor, Cyflor, Resflor and Florkem).
Prevention: Vaccination of Heifers (8 weeks and then 4 weeks prior to calving) as well as Cows (4 weeks prior to calving) with any registered vaccine against salmonellosis. This will ensure there are sufficient levels of maternal antibodies when the calf drinks colostrum.
Biosecurity: Isolation and separation of the affected calf will help prevent the spread of the infection amongst the other calves. Regular disinfection and cleaning is highly recommended.
Coccidia
Coccidiosis is caused by a protozoal organism Eimeria Bovis/ Eimeria Zuernii resulting in a haemorrhagic diarrhoea of calves older than three weeks of age. Coccidia infections are as a result of poor husbandry such as with calves living in dirty, wet calf crate.
Diagnosis: A tentative diagnosis is often made from the macroscopic appearance of the faeces as well as the age of the calf with fresh blood being present in the faeces. A definitive diagnosis is made on a faecal float to identify the coccidia oocysts. A Diff Quick stain of the faeces will also reveal the coccidia merozoite.
Treatment: Symptomatic treatment to maintain the calf’s hydration status is recommended with electrolytes. The use of antibiotics is occasionally warranted in these cases. Antibiotics in the Sulphonamide group (Maxisulf, Norotrim and Sulfatrim). No other antibiotics are effective against coccidia. Anticoccidials such as Baycox and Vecoxan are also effective.
Prevention: Regular disinfection and cleaning is highly recommended. Ensure hygiene is maintained and living spaces are clean and dry at all times.
It is important to note than Coccidia is a zoonotic disease and affects immunocompromised individuals.
Helpful tips to keep in mind!!
- Ensure calf maintains its hydration status. This can be done with supplemental electrolytes such as Electrogaurd and Replensol. Should commercial electrolytes not be available a home remedy of 1 teaspoon salt, 1 teaspoon lemon juice, 1 tablespoon bicarb and 1 tablespoon dextrose/glucose (No Sugar!) in two liters of water. Let the calf drink 1-2L depending on the severity of diarrhoea once daily.
- Do not withhold milk in a case of calf diarrhoea.
- Ensure each calf drinks colostrum 10% of its bodyweight (approximately 4L) within the first six hours of life!!!!!!
- As labour intensive as it is, TLC goes a long way in ensuring survival of the calf.
Thank you for your valued support!
Dr Jarred Morris
BVSc (cum laude)
Tel: 082 559 1941
Email: jarred.morris1@icloud.com