Small Ruminants: Diseases of Growing Lambs Flashcards
What are common clinical presentations of growing lambs?
- Poor growth, diarrohoea
- Sudden death/clostridial disease
- Trace element deficiencies
- Lameness
- Neurological diseases
- Skin diseases
What are the differentials for diarrhoea in lambs?
- Nematodirus battus
- Parasitic gastroenteritis
- Coccidiosis
- Acidosis
- Clostridium perfringens type B (lamb dysentry)
- Clostridium perfingns type D (pulpy kidney)
- E.coli
- Salmonella
What type of pathogen causes cryptosporidiosis?
C. parvum, protozoa, zoonotic
Severe outbreaks at the end of lambing
3-7 days old
What type of pathogen causes cryptosporidiosis?
C. parvum, protozoa, zoonotic
Severe outbreaks at the end of lambing
3-7 days old
How is cryptosporiodisis diagnosed and treated?
Diagnosis- stain faecal smear, PM histology difinitive, E.coli
Treatment- Supportive, oral fluids, 4-6 times daily, drug treatments from calves cascade
How can cryptosporidia be prevented and controlled?
- Reduce challenge- use different fields/housing
- In outbreak move to clean pasture
- Improve hygiene throughout the farm indoor
- Improve resiliance- nutrition
What pathogens cause coccidiosis?
Protozoa, Eimeria crandallis, ovinoidallis
Normally ‘non disease-causing strains in sheep’
What are the risk factors for coccidiosis?
- High stocking
- Inadequate colostrum
- Mixing ages
- Stress
- Concurrent nematodirus
What are the clinical signs of coccidiosis, how is it diagnosed and treated?
CS: 4-8 week old lambs, diarrhoea, blood, fever, weight loss, death
Diagnosis- faecal sample, coccidial count
Treatment- supportive, oral fluids
Drugs- vecoxan, baycox to lambs
How can coccidiosis in lambs be prevented and controlled?
- Reduce risk factors
- Hygiene- pens and feed troughs
- Stocking rates
- Colostrum
- Nutrition
- Batch rearing
What causes acidosis?
- Consumption of rapidly fermentable carrbohydrates
- Managment of concentrates in growing lambs
- Stubble grain crops (wheat and barley)
- Fall in rumen pH
- Lactic acid production
- Rumenitis
- Metabolic acidosis
- Lead liver abscessation
What are the clinical signs of acidosis?
CS- sudden death, dull, depressed, reluctant to move, teeth grinding
How is acidosis in lambs diagnosed and treated?
Diagnosis- history and clinical signs, rumenocentesis ph <5.5
Rumen liqor with no live organisms, PM
Treatment- IV fluids, 7-10% dehydrated (isotonic saline plus bicarb)
Oral fluids by stomach tube
Multivitamins, penicillin for 10 days, Hay
Review feeding
Bloat in sheep is uncommon what is the most likely cause in sheep?
Where does the sheep show distension?
What are the differentials?
How is it treated?
Grain, oesophageal obstruction, legumes
Left sided distension
DDXs- hypocalcaemia, abdominal catastrophes
Treatment- stomach tube, dimeticone (orally), rumen trochar
What are the clinical signs of lamb nephrosis syndrome?
What is the cause?
- 2-12 weeks of age
- Older lambs >4wo, lose condition and have diarrhoea
- Cause- unknown, often concurrent cryptosporidosis
How is lamb nephrosis syndrome diagnosed and treated?
Diagnosis- raised urea and creatinine hyperkalaemia
decreased albumin globulin ration and a metabolic acidosis, on PM pale and swollen kidneys observed
No treatement
What is associated with trace element deficiencies?
Associated with soil, pasture deficiencies or interactions with other elements which reduce availibility to sheep
What should be considered when investigating trace element deficiencies?
- Consider other causes first- poor nutrition, lameness
- Which group of sheep to sample
- When: grazing season
- Which samples to take
- Interpretation of results often tricky- advice
- Response to treatment is often used
- Flock/group treatments
- What deficiency is called ill thrift?
- What is the normal function of the element?
- What are the clinical signs of deficiency?
- Cobalt deficiency-
- consituent of vit b12, rumen synthesis incorporating them, RBC development, amino acid synthesis, energy metabolism
- CS: weight loss, anaemia, slow growth, debility, weight loss, water eye discharge
How is cobalt deficiency diagnosed and treated?
Diagnosis- Co/Vit B12 in blood/liver, response to therapy
Treatment- group, Co rumen boluses, Co oral drenches, Vit B12 injections, Co into creep feed, Pasture treatment
- What causes a selenium deficiency
- What is the function of selenium
- What disease does it cause?
- How is it diagnosed and treated?
- Soil/pasture deficiency
- Anti-oxidant, immune function
- White muscle disease, poor repro performance in ewes, weakness/collapse
- Diagnosis- blood sample, Treatment- oral, injectable, bolus, salts
- When does iodine deficiency affect lambs and what does it cause?
- What is the effect on lambs?
- New born lambs- deaths, weakness illness, late abortions
- Lambs thyroid goitre, more susceptible to other neonatal diseases
What breed are prone to swayback (Cu deficiency)
What breeds are prone to copper poisoning?
Scottish blackface- swayback
Poisoning- north ronaldsay, suffolk, blue faced leicster, texels
What causes acute and chronic copper poisioning?
Acute- ingestion of large ammounts
Chronic- ingestion over period of time
What happens to copper in chronic cases?
Stored in liver in lysosomes, capacity suddenly released into circulation
Maybe precipitated by stress
Intravascular haemolysis and jaundice
What are the clinical signs, diagnosis and treatments for Cu poisoning?
CS: ataxic, headpressing, jaundice, haemoglobinuria, recumbancy and death
Dx- history and clinical signs, PM
Tx- sodium calcium EDTA, supportive therapy, group, remove feed source, molybedenum and sulphur added to water
What are the different agents that can cause pneumonia in lambs?
What lungworms can affect lambs at pasture?
Respiratory viruses- PI3, RSV
Bacteria- mycoplasma, Manheima, Pasturella
Lung worm- Dictylocaulaus filaria
Where is manhaemia haemolytica present normally in sheep?
When does it cause lung disease?
Present in nasopharynx of health sheep
Often secondary to other disease/stress
Epidemiology- housing or pasture, outbreaks
Change in diet, worms, ticks, housing, bad handling
- What are the clinical signs of manhaeimeia haemolytica?
- How does it show PM?
- How is it treated and prevented?
- CS: pyrexia, mucopurulent discharge, cough, increased resp rate, depth dyspnoea
- PM- typical antro-ventral consolidation, culture
- Treatment- oxytet, amoxillin, macrolides, 5-7 days
Prevention- vaccination (heptavac, ovipast), consider group at risk
- What species of mycoplasma causes pneumonia?
- What are the clinical signs?
- What are the risk factors?
- How is it diagnosed?
- Hows is it treated and prevented?
- Mycoplasma ovipneumoniae
- Chronic disease- cough, slight nasal discharge, increased RR, dyspnoea
- Housed, pasture- over stocked lambs
- Dx- history, clinical signs, PM, BAL (uncommon)
- Tx- oytet LA, macrolides
- Px- ventillation, hygiene, stocking rates, risk factors
What bacteria can cause chonic supprative pneumonia?
Lung abscesses
Usually one or two secondary to pneumonia
A. pyogenes, M. haemolytica, P. multocida
Weight loss, pyrexia, soft cough, increased RR, nasal discharge
Prognosis poor, prolonged course penicillin may be helpful
What bacteria can cause chonic supprative pneumonia?
Lung abscesses
Usually one or two secondary to pneumonia
A. pyogenes, M. haemolytica, P. multocida
Weight loss, pyrexia, soft cough, increased RR, nasal discharge
Prognosis poor, prolonged course penicillin may be helpful
What lung worms can affect sheep?
Which are signifficant?
Dictyocaulus filaria
Muellerius capillaris- not significant
- When are lambs infected with lungworm
- What are the clinical signs
- What is the treatment?
- When at pasture- summer/autumn
- Coughing, increases RR, depth, dysponea
- Treatment- anthelmintics (BZ, ML, LV), NSAIDs, supportive
What are the two common presentations of poor growth in lambs?
A small number never grown normally
A large number which have grown normally intitially, then had a specific condition
When there are a few lambs which have never grown correctly what are the differentials?
Low birth weight
Border disease- PI
Congenital problem
Neonatal/chronic infection
Inadequate milk diet- triplet or dam too little milk
When there is a group of lambs with poor growth what are the differentials?
Inadequate nutrition
Parasitic disease
Trace element deficiencies
Pneumonia
Lameness
Orf/scab
How is poor growth investigated?
History- CS, time of year, breed, growth rates, groups, diet, cocci history, trace element treatments
Clinical exam- grazing, sward height, growth rate calc, samples (FEC), blood
Abbatoir feedback
PM if any die
What are the expected growth rates for lambs for the following periods?:
1. 8 week weight growth rates
2. Weaning weight growth rates
3. Sale weight growth rates
- 300-500g/day
- 300-500g/day
- 200-250g/day
