Diseases of the neonatal lamb 2

How does joint ill present?

• Usually at 2-3 weeks, can be earlier

• Sudden onset lameness, single or multiple joints

• Variable response to treatment

  • Antibiotics, NSAIDs

What is the most common aetiological agent causing joint ill?

Streptococcus dysgalactiae subsp. dysgalactiae

(Still do joint tap to confirm bc not only agent)

What is the source of infection of joint ill?

• Orally

• Cutaneous wounds- umbilicus, docking, castration etc.

How is joint ill treated?

• Penicillin in early cases- long course

  • NOT oxytet

• NSAIDs

• Euthanasia in later cases

What are the clinical signs of joint ill caused by erysipelothrix rhusiopathiae

• Lambs 6 wks to 6 months old

• Polyarthritis (fibrinous), pyrexia, lameness

What is the source of infection, treatment an dcontrol for erysipelothrix rhusiopathiae joint ll?

• Skin wounds considered route of infection

• Survives in environment several week

• Same treatment and control as strep dys.

What is navel ill? What are the sequelae?

• Ascending infection leading to abscessation of navel

• Sequaulae- peritonitis, liver abscessation, systemic infection, polyarthrits,

  • Hepatic necrobacillosis with fusobacterium necrophorum

How is navel ill prevented and controlled?

• Total immersion of navel in strong vet iodine, within 15 minutes

• Repeat 2-4 hours later

• Good hygiene and colostrum

How is navel ill treated?

• Penicillin

• Potentiated amoxicillin

What are the common trace element and vitamin deficiencies?

• Iodine deficiency

• Copper deficiency and sway back

• White muscle disease

What is the clinical presentation of iodine deficiency?

• A lot of the time subclinical which if treated can improve other factors

• If clinical presents as goitre, late abortions, minimal fleece in live lambs

What foods can exacerbate iodine deficiency?

• Thiocyanates

  • Swedes, kale, cabbage etc

How can you identify iodine deficiency PM?

• Histopath of thyroid

• Thyroid gland weight >0.4g/kg of liver weight

How do you prevent and treat iodine deficiency?

• Prevention: Ewe supplementation

  • Iodised oil injection

  • Oral dosing 8 and 4 weeks prior to lambing

• Treatment: Oral potassium iodide, 20mg per lamb

What can cause copper deficiency?

• Common in some areas

  • Soil antagonists: iron, molybdenum, sulphur

    • Can improve pasture

What are the signs of Cu deficiency?

• Swayback

• Fine head tremor

• Osteoporosis

• Tendon abnormalities

• Depigmentation of coloured wool, poor quality, steely

• Anaemia

How is swayback diagnosed?

• C/S

• Histopath of brain and spinal cord

• Liver Cu conc. >80mg/kg

Can you treat swayback?

No- euthanasia

How do you prevent Cu deficiency in lambs?

• Supplement but risk of toxicity!!

• Blood and liver tissue samples pre tupping

  • 8 per flock/ 4 per management group

How can you supplement copper?

• Chelated Cu injection (short term)

• Mineralised drenches (short term)

• Mineral supplements (variable intakes)

• Copper capsules and boluses- slow release

Don't provide more than one source

What causes white muscle disease?

Degen of skeletal and cardiac muscle due to Vit E and Sel deficiency

(Aka nutritional muscular dystrophy, stiff lamb disease)

What are the clinical signs of white muscle disease?

Weak lambs with difficulty suckling

How is white muscle disease treated and prevented?

• Tx: potassium selenate, vitamine E

• Prevented by supplementation at least 6 weeks before lambing (can drench)

What are the common congenital malfortmations

• Atresia ani- failure of anus to form properly, can end blinding or open into vagina, urethra or bladder

• Schistosoma reflexa

• Brachygnathia

• Entropion

• Dandy walker malformation

How does atresia ani present?

Cases can be easily missed - swollen abdomen

Can be treated surgically if just atresia ani

What can entropion lead to?

• Keratoconjunctivitis

• Corneal ulceration

• Perforation

• Blindness

How can you treat entropion?

• Surgical excision (cost+++)

• Injection of subconjunct penicillin

• Pinching (quite successful)

• Wound clip (not as successful)

  

What is being shown here? What can be done?

Prolapsed intestine

• Keep clean, surgically prepare, enlarge hole, replace and suture defect

What weights would you expect for lowland day old lambs? (highland lower)

• SINGLE 5.5-7.0KG

• TWINS 5.0-6.0KG

• TRIPLET> 4.0KG

What lamb plasma value indicates adequate and indaequate colostrum transfer?

• <45g/l inadequate

• 45-60g/l borderline

• >60g/l l adequate

What should you look for PM before opening carcass?

• Weight, hardening of feet, carcass ext meconium, trauma, watery mouth, scours, haemorrahge

• Navel ill swollen joints

• Injury bloating anaemia

• Fleece-Borders disease

• Deformities

What should you look for PM when opening thorax and abdomen?

• Open thorax and then abdomen

  • Brown fat around kidneys

  • Presence of milk/colostrum

  • Lung aeration

  • Hepatic rupture

  • Haemorrhages

  • Thryroid gland size

  • Infectious causes

What are some PM indications of dystocia

• Swollen head /tongue

• Meconium staining

• Oedema head shoulders

• Fracture limbs ribs

• Free blood in carcase

• Haemorrhages

What are some PM indications of starvation/ hypothermia?

• No brown fat

• Minimal body far

• No milk in abomasum

What can you do as genetic management to reduce lamb mortality?

• Selection of breeding flock

  • Ewes: Healthy, no mastitis, lameness or broken mouth, good mothers)

  • Ram selection- low dystocia, vigorous lambs

How can you use nutrition to reduce lamb mortality?

• BCS at tupping and throughout pregnancy

• Feed according to scanning, BCS and date

• Silage/ Hay analysis

• Ensure adequate trough space

• Check ewe nutrition with metabolic profiles

• Brix/Ketone meter

What other management techniques should be used to reduce lamb mortality?

• Environmental management

• Lambing hygiene

• Lamb care