Foals Flashcards
What is the difference between a premature and dysmature foal?
Premature: a foal born <320 days of gestation, that displays immature physical characteristics
Dysmature: a full-term foal that displays immature physical characteristics (full-term=340 days)
What is the gestation period of a mare?
Around 340 days
Give some physical characteristics of a premature or dysmature foal
Domed head Short, silky hair coat Floppy ears Low birth weight Weakness, prolonged time to stand Flexor tendon laxity Incomplete ossification of carpal and tarsal bones (not visible on x-ray) Severe cases: multiple organ dysfunction
By what age do foals have autogenous IgG adult levels?
4 months of age
Which immunoglobulins are found in colostrum?
IgG, IgG(T), (IgA, IgM)
What is the half-life of maternal IgG in foals?
20-23 days
Declines by 1-2 months (more rapid if poor levels initially)
How are immunoglobulins absorbed from colostrum?
When does maximum absorption occur?
Specialist enterocytes absorb the immunoglobulins by pinocytosis
They have a maximum lifespan of 24 hours
Maximum absorption occurs within 8 hours of life (foal must ingest 1L of colostrum within the first 6 hours of life)
When do IgG levels peak in a foal’s blood?
18 hours
When should you test IgG levels to evaluate passive transfer?
12-24 hours (later than 24 hours: foal wont be able to absorb colostrum as specialist enterocytes will have died)
Define failure of passive transfer
Inadequate transfer of colostral IgG
What is the normal value for transfer of colostral IgG?
What would be defined as failure of passive transfer?
Normal: >8g/L
FPT: <4g/L
When do foals normally stand after birth?
Within 1 hour
When do foals normally suck after birth?
Within 2 hours
When is IgG not detectable?
< 6hrs old
Give some predisposing factors for failure of passive transfer
- Loss of colostrum via premature lactation (twinning, placentitis, premature placental separation)
- Inadequate colostrum (IgG/volume) production (severe illness, premature foaling, endophyte-infected fescue (plants))
- Failure to ingest adequate volume of colostrum (neonatal weakness, rejection of foal)
- Failure to absorb colostrum (premature foals, concurrent illness of foal, glucocorticoids may hasten maturation of specialist enterocytes)
When is colostrum produced in the mare?
Last 2-4 weeks of pregnancy
How can you test for failure of passive transfer?
- ELISA SNAP test
- RID (radial immunodiffusion)
- ZnSO4 turbidity
- Glutaraldehyde coagulation
- TSP/globulins (not always accurate in sick foals; <50=too few globulins)
- Colostrum specific gravity can be checked pre-suck
How can you treat failure of passive transfer?
- Give plasma (if >12-24 hours old) (from mare, commercial, geldings)
- Give colostrum (from mare, banks, commercial)
What is an immediate risk of failure of passive transfer?
Septicaemia
Give some less immediate risks of failure of passive transfer
When do they tend to occur?
Rotavirus, respiratory disease, joint sepsis
Occurs ay 1-4 moths old after rapid waning of ingested IgG
When do foals normally begin their suckling reflex after birth?
Within 20 minutes
What is the temperature of a newborn foal?
37.2-38.9oC
What is the normal heart rate of a newborn foal?
Birth: 40-80
First week: 60-100
What is the normal resp rate of a newborn foal?
Newborn= 45-60
7 days old= 35-50
By when should meconium be passed in a newborn foal?
Within 24 hours
By when should urine be passed in a newborn foal?
Colts: 6 hours
Fillies: 10 hours
Large volumes of dilute urine
What is the average weight of a newborn foal?
45-55kg
What is the average daily weight gain of a newborn foal?
0.5-1.5kg/day
How much milk should a newborn foal consume?
20-28% BWT (feed every 2 hours)
Which lungsounds are normal in a newborn foal?
Harsh bronchovesicular sounds
Crackles are present in the ventral dependent side if in lateral recumbency
Give some signs of sepsis in a foal’s mm
Petechiae, congestion