HERD HEALTH - Group Lamb Health Flashcards
How should you approach investigating group lamb health?
- History
- Examine environment, housing and nutrition
- Data analysis
- Clinical examination of the lambs
- Clinical examination of the ewes
- Lamb post mortems (PM)
- Additional diagnostic testing
- Implement preventative measures
Which history questions are beneficial to ask when investigating group lamb health?
- How many lambs are affected (in a percentage)?
- How old are the affected lambs?
- What are the clinical signs?
- Have you seen these clinical signs before?
- When did you first notice these clinical signs?
- Have you treated and if so how and what was the response?
- What breed were the ewes and rams?
- What have the ewe body condition scores and nutrition been?
- How old are the ewes?
- Have the ewes had any clinical signs?
- Management at lambing?
- Ewe and lamb vaccination history?
- Colostrum management?
- Umbilical management?
- Lamb tail docking and castration methods and timing?
What data is beneficial to analyse when investigating group lamb health?
Records on number of ewes bred
Ultrasound scanning records
Records of lambs born dead and alive
Records on number of lambs turned out to pasture
Records on number of lambs weaned
Records on number of lambs sold or kept for breeding
When does the majority of lamb mortality occur?
Perinatal stage
Neonatal stage
What are the risk factors for neonatal lamb mortality?
Low lamb birthweight
Low serum immunoglobulin (IgG)
High litter size
Low ewe body condition score
Born late in lambing season
Inexperienced/young mothers
Male lambs
Orphan lambs
How does low lamb birthweight increase the risk of neonatal mortality?
When lambs are born, they have a big surface area but low body mass and thus are prone to hypothermia, so they have brown adipose tissue to generate heat. However, lambs with decreased body weight have decreased brown adipose stores and thus are at increased risk of hypothermia
At which birthweights is there increased risks of lamb mortality?
Less than 3.5kg
More than 5.5kg (increased dystocia risk)
Which two main factors influence lamb birthweights?
Genetics
Nutrition
Be aware that farmers often restrict feed to try and prevent big lambs and dystocia, but this can lead to low birthweights and mortality - advise them that keeping feed conistent is better if the genetics are appropriate
How does a low ewe body conditon score increase the risk of lamb mortality?
Ewe body condition score affects lamb viability, mothering, colostrum and milk quality and quantity
Why does being born late in the lambing season increase the risk of lamb mortality?
The lambing facilities are more contaminated near the end of the lambing season, so there is increased risk of disease and mortality
What are orphan lambs at an increased risk of mortality?
Poor colostrum provisions
Nutrition is very artificial
Increased risk of red gut
What is red gut in orphan lambs?
Red gut is the term used to describe the inflammation and distension of the intestines in orphan lambs often as a result of their artificial nutrition
How can you prevent red gut in orphan lambs?
Feed warm milk for the first 7 days and then bring temperature down to room temperature
Ensure adequate fibre intake
Wean off of milk early
What are the basic steps of a lamb post mortem (PM)?
- Assess the outside of the lamb, checking the head, hooves, tail and naval
- Remove the skin
- Open the abdomen
- Open the thorax
What is a key sign the lamb breathed when alive, on post mortem (PM)?
If the lungs are pale pink and float in water, this indicates the lamb breathed in life
What is a key sign the lamb suckled when alive, on post mortem (PM)?
Milk present in the abomasum (but be aware the lamb may have been stomach tubed)
Meconium has been passed
What is a key sign that the lamb walked when alive, on post mortem (PM)?
No soft ‘slippers’ covering the soles of the hooves
What are key signs of dystocia on lamb post mortem (PM)?
Swollen head
Oedema over the hindquarters
Meconium staining
Fractured ribs
Ruptured liver
What is a key sign that the lamb metabolised its brown adipose tissue in life, on post mortem (PM)?
Metabolised cardiac and renal fat will have a purplish appearance
Which additional factors should you assess on lamb post mortem (PM)?
Evidence of infectious disease
Evidence of goitre
Evidence of a congenital abnormality
Which additional diagnostic tests could you do to investigate group lamb health?
Make sure to consider if these are necessary and will have any affect on your treatment/prevention plan
Brix refrectometry (colostrum and serum) to assess passive transfer
Ewe dietary analysis
Ewe metabolic profiling
Bacterial culture
Toxin isolation
Parasitology
Virus isolation
Serology
Histopathology
What can be done to prevent lamb mortality?
Optimise ewe nutrition
Vaccinations
Hygiene
Good lighting
Monitoring
Stocking density
Compact lambing season
Colostrum management
Umbilical management
How can a compact lambing season help to prevent lamb mortality?
A more compact lambing season means the ewes give birth at around the same time, so there will be less lambs born at the tail end of the season that will be exposed to increased contamination and be at an increased risk of mortality
How quickly should lambs ingest colostrum?
Lambs should ingest colostrum within 2 hours following lambing
How much colostrum should lambs receive within their first feed?
Lambs should receive 50ml/kg of colostrum in their first feed
How much colostrum should lambs receive within their first 24 hours of life?
Lambs should receive 200 to 300ml/kg of colostrum in their first 24 hours of life
How can you check lambs in an outdoor lambing system have ingested colostrum?
It is harder to monitor colostrum ingestion in lambs in an outdoor lambing system, however you can assess if their tummys are full and they seem BAR (whilst ensuring they don’t have abdominal distension due to watery mouth)
What should you do if the lamb’s own mother’s colostrum is not available?
Use fresh colostrum from another sheep from the same farm
Use frozen colostrum from another sheep from the same farm
Use bovine colostrum
Use artifical colostrum
What is the risk of giving probiotics to lambs before they have their first feed of colostrum?
The nutritional content of pobiotics can stimulate closure of the enterocytes resulting in decreased IgG absorption from the colostrum
What should you be aware of if using bovine colostrum for lambs?
It is important to make sure the cow is vaccinated against clostridial disease and is Johne’s and tuberculosis free. Furthermore, cow colostrum should be pooled before given to lambs as some cows can produce antibodies agaisnt sheep erythrocytes, resulting in neonatal isoerythrolysis. Pooling the colostrum from multiple cows reduces this risk
What are some of the most common diseases you will see in lambs?
Starvation/hypothermia
Watery mouth
Neonatal diarrhoea
Neonatal bacteraemia
Orf
Congential conditions
Umbilical prolapse
Neonatal isoerythrolysis due to cow colostrum
What are the clinical signs of starvation and hypothermia in lambs?
Dull, curled up lambs, often away from the dam
How long do the brown adipose tissue reserves last in lambs?
The brown adipose tissue reserves last approximatelt five hours in lambs
What are the possible underlying causes of starvation and hypothermia in lambs?
Mismothering
Maternal mastitis
Trauma from birth
Concurrent disease
How do you treat mildly hypothermic (37-39°C) lambs?
Stomach tube
Warm the lamb (heat box or lamp)
How should you treat severly hypothermic (less than 37°C) lambs that are less than 5 hours old?
If the lambs are severely hypothermic but less than 5 hours old, warm them (heat box or lamp) and stomach tube them
How should you treat severly hypothermic (less than 37°C) lambs that are more than 5 hours old?
If the lambs are severely hypothermic and more than 5 hours old, if they can hold their head up stomach tube and warm them (head box or lamp). If they can’t hold their head up, give a intraperitoneal glucose injection and warm them
What is the typical signalement for watery mouth?
Lambs 1 to 3 days old, more common in the lambs born at the end of lambing season
What are the risk factors for watery mouth?
Failure of passive transfer
Born late in the lambing season
What are the early clinical signs of watery mouth?
Dull
Cold, wet mouth
Reluctance to suckle
What are the later clinical signs of watery mouth?
Hypersalivation
Abdominal distension
Scour or constipation
Recumbent
How do you treat watery mouth?
Oral fluid therapy
NSAIDS
Antibiotics
Warming
Be aware watery mouth is very challenging to treat
How can you prevent watery mouth?
Colostrum management
Hygiene
Compact lambing season
Prophylactic antibiotics (DONT ENCOURAGE THIS)
Which pathogens cause neonatal diarrhoea in lambs?
E. coli
Cryptosporidium
Salmonella
Rotavirus
Lamb dysentery
Coccidia
How do you prevent enterotoxigenic e. coli (ETEC) in lambs?
Hygiene
Colostrum management
What is the typical signalement for enterotoxigenic e. coli (ETEC) infection in lambs?
Lambs less than 2 days old
What are the clinical signs of enterotoxigenic E. coli (ETEC) in lambs?
Severe brown diarrhoea
How do you treat enterotoxigenic e. coli (ETEC) in lambs?
Fluid therapy
NSAIDs
Antibiotics
Which salmonella species typically cause diarrhoea in lambs?
Salmonella typhimurium
Salmonella dublin
What is the main clinical sign of salmonellosis in lambs?
Haemorrhagic diarrhoea
Clinical signs of enterotoxaemia
How do you treat salmonellosis in lambs?
Fluid therapy
NSAIDs
Antibiotics
At what age does coccidia cause diarrhoea in lambs?
Coccidia can cause diarrhoea in lambs over 3 weeks old
Which pathogen causes lamb dysentery?
Clostrdium perfringens type B
What are the clinical signs of lamb dysentery in younger lambs (1 - 3 days old)?
Sudden death
Haemorrhagic enteritis on post mortem (PM)
What are the clinical signs of lamb dysentery in older lambs (up to 3 weeks old)?
Abdominal pain
Haemorrhagic diarrhoea
Sudden death
How can you diagnose lamb dysentery?
Clostridium perfringens toxin isolation from diarrhoea
Post mortem (PM)
How do you treat lamb dysentery?
Euthanasia indicated for most cases
How can you prevent lamb dysentery?
Clostrial vaccination of ewes
Colostrum management
What are the clinical signs of mild naval ill in lambs?
Hot, swollen and painful umbilicus
± Pustulent discharge
What are the clinical signs of severe naval ill in lambs?
Hot, swollen and painful umbilicus
± Pustulent discharge
Depression
Failure to suckle
Pyrexia
± Lameness
How do you treat naval ill in lambs?
Long course of systemic antibiotics (ideally 10 to 14 days)
NSAIDs
How do you prevent naval ill in lambs?
Hygiene
Colostrum management
Umbilical management
How does meningitis typically present in lambs?
Sudden death
Why is septic arthritis (‘joint ill’) so challenging to control in lambs?
Septic arthritis (‘joint ill’) is so challenging to control in lambs as it is typically caused by streptococcus dysgalactiae which resides in dry straw and thus difficult to eradicate from lambing environments
How do you treat septic arthritis (‘joint ill’) in lambs?
10 - 14 days antibiotics
NSAIDs
How do you prevent septic arthritis (‘joint ill’) in lambs?
Hygiene
Colostrum management
Umbilical management
How does septicaemia typically present in lambs?
Sudden death
What are some of the key signs of septicaemia in lambs on post mortem (PM)?
Haemorrhage
Oesophageal ulceration
Focal grey hepatic lesions
What is orf?
Orf if an infectious dermatitis caused by pox virus that typically affects the mucocutaneous junctions of the lips of lambs. Ewes nursing infected lambs can develop lesions on their teats
What are the consequences of orf?
Orf lesions prevent the lambs from suckling and the ewes will resist suckling due to the lesions on their teats
(T/F) Orf is a zoonotic disease
TRUE.
How do you treat orf?
Antibiotics if there is secondary bacterial infection
NSAIDs
Feed the lambs
What are the main causes of congenital abnormalities in lambs?
Border disease
Schmallenburg virus
Blue tongue virus
Mineral deficiencies
Teratogenic toxins
Hereditary conditions
What are the signs of border disease in a sheep flock?
Be aware ewes and lambs will be persistently infected with border dsease
Abortion
High barren rates
Congenital deformities in lambs
What are the clinical signs of border disease in lambs?
Low birth weight
Weakness
Limb deformaties
Domed head
Neurological signs
Wiry wool
Abnormally pigmented wool
Which hereditary congenital conditions are commonly seen in lambs?
Entropion
Atresia ani
