Diseases of the neonatal lamb 1

What are the causes of still born lambs/ lambs dead in first 24 hours?

• ‘Birth stress’ resulting in a failure to suck, hypothermia etc.

• Anoxia/hypoxia

• Ruptured liver

• Fractured ribs

• Brain haemorrhage

List some of the causes of post partum neonatal lamb losses?

• Hypothermia

• Starvation

• Infections

• Predation

• Accidents

• Congenital defects

List some of the common infections causing neonatal lamb death

• Watery mouth

• Salmonella

• Cryptosporidia

• Septicaemia

• Meningitis

• Joint ill

• Clostridial Disease

• Pasturellosis

What volume of colostrum should a lamb receive in first feed and in first 24 hours?

• 50 ml/kg first feed

• 200ml/kg in 24 hours

What is the main methods used to assess passive transfer?

• Brix threshold- 26%

• Serum TP 5.5g/dL- do a good sample size

What are the risk factors for poor colostrum intake?

• Concurrent disease- dystocia, lameness, fluke

• Under nutrition of ewe

• Breeding- mothering, lamb vigour

• Age of ewe

• Multiple births

• Lambing environment

What are some of the substitutes that can be used for colostrum?

1. Ewe colostrum (spare from other sheep)

2. Goat colostrum (must be CAE -ve flocks)

3. Cow colostrum

4. Commercial colostrum substitues

What are the limitations of cow clostrum?

• Need to be Johnes and TB negative

• Less energy so need 30% more

• Immunological anaemia not common but can affect a lot of lambs in flock 10-20 days

• Can have colostrum tested

• Vaccinate clostridia

List some of the causes of. primary hypothermia

• Out-door lambing

• Younger ewes

• Wet weather

• Small birth weight

• Failure to feed

How can hypothermia be prevented?

• Later lambing period

• Genetics- good mothers

• Ewe nutrition

• Provide field shelter

• ID at risk lambs and give special attention

• Lamb coats

What should you make sure before warming a lamb?

• Don't warm hypoglycaemic lamb without giving glucose first

  • Will have hypoglycaemia fit

  • Use I.P. glucose

• Oral admin of fluid to hypothermic lambs can cause regurg and inhalation pneumonia if not holding head up

What is the approach to starvation in a lamb?

• Holding its head up: stomach tube

• Not holding head up: IP 20% glucose solution

What are the common enteric diseases that can affect neonates?

• Watery mouth

• Lamb dysentery

• ETEC

• Septicaemia/meningitis

  • Pasteurellosis

• Rotavirus

• Salmonella spp.

• Cryptosporidium parvum

• Drunken lamb syndrome

What are the clinical signs of watery mouth?

• 12-72 hours of age

• Dull

• Unwilling to suck

• Normothermic

• ‘watery mouth’ - saliva drooling from the muzzle.

  

• Profuse lacrimation

• Frequently accompanied by abomasal tympany

  

• Scouring unusual – constipation/retained, meconium often present

What are the consequences of watery mouth?

• Death within 24 hours common

  • Hypoglycaemia, hypothermia, lactic acidaemia

What are the ddxs for watery mouth?

• Lamb dysentery

• ‘Neonatal Scours’ – E.coli K99, Rotavirus, etc.

• ‘Drunken lamb syndrome’ (lamb D-lactic acidosis syndrome)

Explain the aetiology and pathogenesis of watery mouth

• Endotoxaemia caused by E. coli linked with unhygienic environment

• Terminal hypoglycaemia, lactic acidaemia and lecuopenia

• Delayed abomasal empyting in clinical cases

What are the risk factors for watery mouth?

• Increased litter size

• Lamb size – smaller lambs

• Ewe condition

• Time

• Colostrum??

• Housed lambs

How is watery mouth treated?

Not great evidence for treatment try-

• Antibiotic

• NSAID

• Glucose/electrolyte solution by stomach tube

How is watery mouth prevented and controlled?

• Adequate colostrum

• Clean dry bedding

• Cleaning and disinfection

What causes lamb dysentery?

Clostridium perfringens type B

How does lamb dysentery present?

• 1-3 days of age

• Sudden death

• Hemorrhagic diarrhoea in some cases

• PM- dark red intestines, blood stained peritoneal fluid, pale friable liver

  

How is lamb dysentery prevented?

• Vaccination of ewes with multivalent clostridial vaccines

• – Good passive transfer of MDA

When does ETEC occur? What are the signs?

• • First 24-48 hours of age

• • Watery brown diarrhoea

How is ETEC treated and controlled?

• Treatment with fluid therapy

• • Control through hygiene , adequate colostrum intake, isolation of sick lambs

• • Oral antibiotics

What are the main species of salmonella that cause issues in lambs? What do they cause?

• S. typhimurium

• S. dublin

• Intestinal inflammation, reduced absorption, increased secretion

• Bacteraemia and endotoxaemia

What are the clinical signs of neonatal salmonellosis?

• Weakness

• Profuse watery diarrhoea

• Blood stained

• Dehydration

• Death

How is neonatal salmonellosis diagnosed?

• Culture (warn about zoonosis)

What does cryptospridium parvum cause?

• Villous atrophy in distal small intestine

• Malabsorption, secondary fermentation and diarrhoea

• Not very common bc tend to turn out before an issue (usually seen in pet lambs)

How do you treat crypto?

• Supportive oral fluid therapy

• Paromomycin

What is drunken lamb syndrome?

Aka lamb nephrosis, lamb D lactic acidosis syndrome

(Sporadic outbreaks)

• Gut pathogens entering stomach causing villous atrophy, metabolic acidosis from D lactic acidosis

What are the clinical signs of drunken lamb syndrome?

• 7-10 days and 1-2 months

• Ataxia

• Stop sucking

• Recumbent and depressed

• High mortality ~ 100%

How is drunken lamb syndrome treated?

• 400ml of warm tap water

• 35g of Na bicarb

• 50ml given as a single oral bolus

How is drunken lamb syndrome prevented?

• Hygiene

• • Colostrum?

• • Smaller lambs more at risk

• • Towards the end of lambing