Calf Diarrhea Management Quiz

Neonatal Calf Gastrointestinal Disease

• Neonatal calves are susceptible to gastrointestinal (GI) disorders, significantly impacting their survival and productivity.
• Losses from calf scour are substantial, and prompt, appropriate treatment is crucial for survival.
• Cost of the problem is significant: £44 per sick calf (excluding labour), £123 per sick calf, £36.91 per calf born. (Veterinary, Deaths, Capital, Calf value)
• Factors like dehydration, acidosis and gut damage contribute to mortality.
• Diarrhoea affects 48.2% of pre-weaned calves.

Learning Objectives

• Construct a differential diagnosis list based on clinical presentations, associated with neonatal GI diseases, and choose appropriate diagnostics.
• Determine suitable medical and surgical interventions for the management and treatment of neonatal GI diseases in ruminants.
• Assess individual animal and herd prognosis.
• Define control measures for preventing neonatal GI disease.

Aetiological Agents

• Nutritional: Milk replacer quantity and quality, mixing, temperature, irregular feeding, and poor weaning management.
• Stress: Associated with poor weaning management, irregular milk feeding and other variables.
• Infectious:
• Viruses - Rotavirus, Coronavirus (BVD)
• Bacteria - E. coli, Salmonella, Clostridium
• Protozoa - Cryptosporidia, Coccidia

Diarrhoea

• Rotavirus and Coronavirus: Picked up in calving pens, spread among calves. E. coli F5/K99 is a factor in early diarrhoea.
• Salmonella: Neonatal or older, different presentations, from carrier animals
• Clostridium perfringens: Toxin A and B are implicated
• Cryptosporidium: Environmental pressures, oocysts are immediately infective
• Coccidia: Eimeria bovis/zuernii/alabamensis, oocysts need to sporulate in the environment.

Diarrhoea - Duration of Disease

• E. coli (chronic and acute): Under 5 days, Chronic Birth to 3 months

• Rotavirus: 5 to 10 days, 1 to 2 weeks

• Salmonella: 2 to 6 weeks

• Coronavirus: Few days to a few weeks

• Cryptosporidia: 21 days to 2 years

• Coccidia: 5 to 35 days

Hypersecretory vs Malabsorptive

• Malabsorptive: Damage and loss of intestinal cells are higher than cell replacement, leading to reduced surface area for nutrient and water absorption resulting in osmotic diarrhoea
• Hypersecretory: Pathogens like E. coli and Salmonella cause overproduction of fluid, overwhelming the gut's absorptive capacity. Rotavirus is implicated in both categories.

End Result

• Dehydration and metabolic acidosis (electrolyte imbalance or D-lactate build-up)

D-Lactate Acidosis

• Damage to intestinal enterocytes allows undigested carbohydrates to reach the large intestine.

• This acidification favours lactic acid-producing bacteria.

• D-lactate production also occurs from ruminal milk drinking.

• Lower palpebral reflex, broad-based stance and ataxic movements are clinical signs indicating a problem in the brain.

Hyperkalaemia

• Diarrhoea causes potassium imbalance (hyperkalaemia).

• Potassium loss from the body in diarrhoea is complicated by its role in buffering H+ in the blood.

• Impairment of sodium/potassium ATPase disrupts electrolyte levels, resulting in increased intracellular sodium and extracellular potassium.

• Leads to neuromuscular excitability, muscle weakness, inability to stand, and severe dehydration and bradycardia.

Diagnostics

• Enable determination of the correct treatment based on clinical signs.
• It may not always be possible to differentiate specific pathogens based on clinical signs.
• Use rapid on-farm diagnostics like "rainbow tests".
• Consider ELISA, lab PCR, faecal egg counts, haematology, and biochemical tests.

Treatment Considerations

• Oral rehydration therapy, IV fluid therapy based on dehydration severity and status
• Identifying and addressing the hydration status of the calf.
• Fluid therapy response time can vary depending on the underlying cause.

Treatment Decisions Tree

• Monitor animal demeanour, milk intake and haemochezia
• Check if there is fever, determine if there is a loss of appetite
• Clinical assessment of the diseased animal
• Administer appropriate drugs and treatments as per diagnosis.

Other Therapies

• Specific Therapies: Antibacterial, antiprotozoal, and NSAID treatments
• Diagnosis is critical to direct treatment.

Vaccination

• Rotavirus, Coronavirus, E. coli F5 K99 adhesin are target pathogens.
• Vaccinate cows/heifers 12-3 weeks prior to calving.
• Boost colostral antibodies
• Reduce occurrence, intensity and virus shedding

Risk Factors

• Environmental factors: Group size, stocking density, inter-batch disinfection, dry bedding
• Management factors: Mixing ages, feeding practices, nutrition, milk feeding, concentrate provision, forage, cleanliness, and external stressors.

Monitoring Calves and Changes

• Assessing body weights, growth rates, average daily gain.
• Evaluating passive transfer function (protein level, <10 days old).

Prevention

• Colostrum management (quality and quantity).
• Hygiene (cleaning and disinfection of facilities).
• Vaccination (administer to cows/heifers 12-3 weeks before calving).
• Feeding management (practices for prevention of bloat)

Other Conditions

• Calf Diphtheria: Caused by Fusobacterium necrophorum. Necrotic stomatitis (cheeks) and necrotic laryngitis (larynx) are common presentations.
• Ruminal Tympany/Bloat: Accumulation of gas in the rumen, caused by feeding errors. Clinical signs include rapid onset colic and an observable distended rumen; treat with a stomach tube.
• Atresia Coli and Ani: Congenital defects with absence of the anus or impaired colon function. Clinical signs include gradual abdominal distension and, in the case of atresia coli, no passing of faeces. Euthanasia is typically needed for these cases.