Failure of lambs and kids to thrive

Question 1

Failure to thrive
- common signs?
- common conditions?

Answer 1

• Impaired growth is a common sign
• Low case fatality
• Substantial morbidity
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• A common feature of many diseases
• Pneumonia (Mycoplasma ovipneumonia)
• Orf
• Neonatal diarrhea
• Coccidiosis
• GI nematodes

Question 2

Mycoplasma pneumonia
- signs? presentation?
- agent
- other concurrent lesions?

Answer 2

• Atypical pneumonia/coughing syndrome
• Lambs/kids that cough, may only appear
  mildly ill or normal other than the cough
• Agent: Mycoplasma ovipneumonia
• Occasionally other Mycoplasma species
• Potential secondary lung abscesses caused by Truperella pyogenes

Question 3

Mycoplasma pneumonia
- seasonality
- risks
- along with what?
- prevalence

Answer 3

• More common in winter
• Increased stocking density increases risk
• May be in conjunction with more severe pneumonia agents (covered in last lecture)
• Typically > 10 % of the group affected

Question 4

Mycoplasma pneumonia
* Clinical findings:

Answer 4

• Mild to moderate fever
• Depressed
• Typically still some appetite, not empty
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• Lots of coughing in the group
• Spasmodic
• Productive
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• Poor growth rates

Question 5

Mycoplasma pneumonia
* Post-mortem changes

Answer 5

anterior-ventral inflammation and consolidation
* Typically this is noted at slaughter – mortality is uncommon, many appear normal

Question 6

Mycoplasma pneumonia
* Treatment, control vaccine

Answer 6

Treatment
* Often does not respond well to antibiotics
* Treat only those with fever and depression
* As a result - metaphylaxis is not indicated
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Control
* Limit stocking density, control microclimate (bedding clean and dry), and air quality
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Vaccination
* There are proponents of administering MLV intranasal IBR/PI3 vaccines to lambs (e.g. Inforce)
* There is evidence that this is not clinically helpful, but continues to be popular

Question 7

Orf
- what is it?
- Presenting complaint
- agent, properties, transmission

Answer 7

• AKA sore mouth, contagious ecthyma, scabby mouth
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  Presenting complaint
• Scabs on faces of lambs and kids
• Scabs on teats/udders of lactating does/ewes
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  Etiology
• Parapox virus (orf virus)
• Very contagious
• Zoonotic!

Question 8

Orf
- who gets it?
- environmental survival?
- carriers?
- immunity?

Answer 8

• Common in youngstock
• Virus can exist in dried state for decades
• Recovered animals can be carriers
• Outbreaks are followed by flock/herd level immunity

Question 9

Orf
- lesions, locations
- who get it worse?
- issue with lactating ewes

Answer 9

• Proliferative lesions
• Externally on face, lips, poll, legs
• Occasionally internal oral cavity, esophagus
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• Worse in immunologically stressed animals (e.g. concurrent pneumonia or coccidiosis)
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• For lactating ewes - can have secondary infections with Staph aureus, can cause teat scabs or may be associated with gangrenous mastitis

Question 10

Orf
(also in humans)
- Tx
- disease course
- prevention

Answer 10

• No specific treatment to reduce disease
• Typical disease course is ~ 6 weeks
• Topical antiseptics if very severe
• For ewes with teat lesions, consider metaphylactic treatment for mastitis
• Control any concurrent morbidities
• There is a vaccine in the US, not in CAN
• Wear gloves, use disinfectant

Question 11

Neonatal diarrhea
* Agents causing outbreaks of diarrhea in young lambs or kids, and timing:

Answer 11

• Enterotoxogenic / Enteropathic E. coli (2 - 7 days)
• Rota virus / Corona virus (2 – 21 days)
• Cryptosporidia (dairy kids) (2 – 42 days)
• Salmonella – any age, not common
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• Clinical signs, epidemiology, treatment, and control are the same as for calves!

Question 12

Take home messages
- Failure to thrive - what general properties of disease cause this?
- what common diseases

Answer 12

• Failure to thrive is an important presenting complaint – typically this reflects diseases with low case fatality but substantial morbidity, which reduces feed conversion – more energy is tied up dealing with disease challenges
• Common diseases causing poor growth include pneumonia caused by Mycoplasma, orf, neonatal diarrhea (bacterial/viral), coccidiosis, and GI nematodes

Question 13

Take home messages
- Mycoplasma presentation, concurrent pathogens
- risk factors, control

Answer 13

• Mycoplasma pneumonia causing lots of coughing in a group, some lambs may look mildly ill, but often many appear normal
• A Mycoplasma outbreak may also be in conjunction with Mannhemia or Bibersteinia (covered last lecture) which can be more severe
• Mycoplasma outbreaks are a disease of stocking density and air quality – while antibiotics are useful for more severe cases (fever, depressed), improving air quality and stocking density will be more useful than metaphylaxis for a group

Question 14

Take home messages
- Orf - type of pathogen, lesions, risks, control
- who gets it? disease course?

Answer 14

• Orf is a pox virus causing scabby lesions typically on the mouth of lambs/kids, and the teats/udder of their dams (spread by the lambs)
• Orf is zoonotic! Wear gloves when handling animals with lesions
• Orf is worse in stressed animals, e.g. those with concurrent disease
  such as pneumonia or coccidiosis
• Typically in mild cases, no treatment is needed and it will resolve in approximately 6 weeks