Infectious diseases of neonatal calves

Question 1

What is the most common neonatal disease in ruminants?

Answer 1

Diarrhoea

Question 2

What is the most common neonatal disease in ruminants?

Answer 2

Diarrhoea

Question 3

Name some other common neonatal diseases of ruminants

Answer 3

• Navel ill
• Joint ill
• Septicaemia
• Bloat (abomasum and rumen)

Question 4

How are most neonatal diseases transmitted?

Answer 4

via faecal-oral route

Question 5

What are some epidemiological considerations surrounding neonatal ruminant disease?

Answer 5

• The reservoir
• The modes of transmission and the agent characteristics related to each
• The incubation period
• The period of communicability.
• Cleaning and disinfection is critical in breaking transmission cycle

Question 6

Describe cleaning to break disease transmission cycles

Answer 6

• Remove organic material: straw, bedding, faecal material
• Destruction of microbes follows first: order logarithmic decay
• Smooth surfaces preferable: reduce organic build up

Question 7

What are some key points to note and consider on a neonatal clinical exam?

Answer 7

• Demeanour
• Suck reflex
• Temperature, pulse, respiration
• Faeces
• Navel
• Hydration status
• Acid - base status
• CNS signs
• Patent anus
• Cleft palate
• Abdominal distention

Question 8

What are some diagnostic methods used in neonates?

Answer 8

• Chest sounds
• Ultrasound
• CSF tap
• ZST / TP***** - assessing passive transfer
• Post mortem exam

Question 9

Naval ill is transmitted via which route?

Answer 9

Infection via navel or oro-respiratory route

Question 10

What is the key sign of naval ill?

Answer 10

Hard swollen naval

Question 11

What occurs in sequelae to naval ill?

Answer 11

Peritonitis
Septicaemia
Polyarthritis- joint-ill

Question 12

What are the risk factors for naval ill?

Answer 12

• Pathogen load: hygiene at calving
• Patent navel: is navel dressed - Strong Iodine.
• Immune status of calf: colostrum intake (FTP)

Question 13

How is naval ill diagnosed?

Answer 13

• Clinical examination: Swollen & hard, Check for hernia
• Probe
• Ultrasound

Question 14

What will be seen on ultrasound of a calf with naval ill?

Answer 14

• Peritonitis: fluid build up in the abdomen, if more advances may also see fibrin strands
• Extension up the vessels: artery to bladder and vein to liver

Question 15

How is naval ill treated?

Answer 15

• Antibiotics
• Drain abscess
• Surgery:
  Remove infected umbilical arteries and urachus.
  If veins affected – poor prognosis (liver involvement)

Question 16

Joint ill is also called?

Answer 16

Septic arthritis

Question 17

Joint ill occurs in sequelae to?

Answer 17

Naval ill

Question 18

What are the signs of joint ill?

Answer 18

Single or multiple swollen and painful joints

Question 19

Describe the treatment of joint ill

Answer 19

• Reduce bacterial load
• Antibiotics: 2+ week course following clinical improvement. Start early. Begin with IV.
• Oxytet. Or penicillin are good first line choice (should be guided by C&S).
• Joint lavage: useful but often hard to do (needles plug up with fibrin)
• Anti-inflammatory
• Poor prognosis

Question 20

Define bacteraemia

Answer 20

Bacteria in blood
Secondary to mucosal damage
E.g. rumen acidosis, mastitis, gum disease

Question 21

Define septicaemia

Answer 21

• Bacteria multiplying in blood
• Concurrent endotoxaemia: “cytokine storm”, Membrane permeability “shot”
• FATAL

Question 22

What are the common agents involved in septicaemia?

Answer 22

E. coli (specific serotypes), actinomyces, staph, Salmonella etc etc.

Question 23

What is the prime cause of septicaemia?

Answer 23

Lack of colostral antibodies

Question 24

Describe an animal with septicaemia

Answer 24

Usually seen from 1 - 5 days of age - Can be later (decline in IgM at 5d)

• Endotoxaemia (sepsis)
• Invariably fatal

Question 25

What are the risk factors for septicaemia?

Answer 25

- Pathogen load in the calving and calf rearing areas | - Immune status due to colostrum intake (IgG and IgM): failure of passive transfer

Question 26

What are the clinical signs of septicaemia?

Answer 26

- Non-specific - Collapsed - Shocked (endotoxaemia) - Very congested conjunctiva: Petechiae, DIC - CNS signs sometimes - Diarrhoea is not a sign but septicaemia may occur at same time as diarrhoea

Question 27

How can septicaemia be treated?

Answer 27

``` Very rarely successful !! Antibiotics NSAID – flunixin Corticosteroid 1mg/kg Fluid therapy Supportive nursing, warmth, feeding etc ```

Question 28

Name some congenital defects of calves

Answer 28

- Cardiac e.g. patent ductus arteriosus, VSD - Atresia ani and atresia coli - Cleft palate - Contracted tendons - Cataracts: BVD - Cerebellar hypoplasia: BVD - Foetal monsters

Question 29

Name two common calve diseases

Answer 29

Calf diphtheria | Bloat/abdominal swelling

Question 30

What is the aetiological agent of calf diptheria

Answer 30

Fusiformis necrophorum

Question 31

What is the other name of calf diptheria?

Answer 31

Laryngeal necrobacillosis

Question 32

Describe the signs of calf diptheria

Answer 32

``` Oral lesions Sore mouth Salivation & foul smell Ulcerative lesions Swollen neck ```

Question 33

What is the cause of calf diptheria?

Answer 33

Dirty buckets – poor hygiene

Question 34

How is calf diphtheria treated?

Answer 34

Tx – penicillin | Steroids for inflammation

Question 35

Abomasal bloat affects calves most commonly at what age?

Answer 35

1-2 weeks old

Question 36

Left sided abdominal swelling indicates?

Answer 36

Bloat – free gas in abomasum (could be rumen mature animals)

Question 37

Right sided abdominal swelling indicates?

Answer 37

``` Could be bloated abomasum again “abdominal catastrophe” e.g. volvulus, torsion etc Calf is very sick Laparotomy indicated ```

Question 38

What is an alternative cause of abdominal swelling?

Answer 38

Atresia coli – gradual distension over first few days – total absence of faeces -> Euthanasia

Question 39

Describe the approach to the swollen calf

Answer 39

- Full clinical exam - Pass stomach tube Is distension completely resolved? Yes – Rumen Bloat No – is R side still swollen - Listen to guts before & after passing tube: Pings, splashing

Question 40

How is abomasal bloat treated?

Answer 40

Sedate (0.1mg/kg xylazine) and role onto back. | 16 gauge needle into “ping”

Question 41

How is ruminal bloat treated?

Answer 41

Relieve distension with tube If repeated: - “Red Devil” trochar/fistula - Correct underlying risk factors!

Question 42

Describe the two causes of rumen bloat?

Answer 42

1. Rumen drinkers - milk goes into rumen, failure of closure of oesophageal groove, ferments -> metabolic acidosis 2. Poor rumen development - often pot bellied, rumen acidosis at weaning