Prevention and treatment of neonatal ruminant disease Flashcards
Name the 5 interlinked perinatal physiological problems that can occur in ruminant neonates?
- Inactivity/lethargy
- Hypothermia
- Hypoxaemia
- Acidosis
- Hypoglycaemia
Define congenital abnormalities
Abnormalities in structure or function present at birth
Aetiology: genetic or environmental
Name some examples of congenital abnormalities in calves
- Patent ductus arteriosus
- Ventricular septal defects
- Patent urachus
- Dwarfism
- Polydactyly
- Cataract
What is the most common cause of perinatal maladaption?
Dystocia
What 3 maladaptation’s occur due to dystocia?
Respiratory
Metabolic
Physical
What is the end result of dystocia maladaptation’s?
Acidosis and hypoxemia
What are the consequences of dystocia maladaptation’s?
Failure to nurse and reduced antibody absorption → failure of passive transfer
How can maladaptation’s be diagnosed in calves?
- Stethoscope and thermometer!
- Blood gases: not very practical
- Time to sternal recumbence: should be less than 5 minutes. If > 9 minutes - increased risk of death
Describe the ABC of resuscitation
- Airway: Intubate, sternal recumbency, pull tongue out
- Breathing: Ambubag, blow down tube
- Circulation: fluids
What are some other resuscitation techniques?
- Cold water down the ear
- Rub with straw
- Acupuncture point on philtrum (GV26)
- Doxapram hydrochloride (2-5 mL) – sublingual drops, s.c. or IV
Calves are born immunologically naïve so what comonents must colostrum contain?
- Fat (50% more) and protein (4x more than normal milk)
- Immunoglobulins (~80% of protein)
- Vitamins (<8x more) and minerals (2-20 x more)
- Immune cells
- Others: growth factors, enzymes, cytokines
30% of dairy calves in UK receive inadequate immunoglobulin transfer …. WHY?
- High genetic merit dairy cows have poor quality colostrum: Dilution effect so calf needs more
- Conformation: big teats etc.
- Supervision: 34% of calves don’t suck within 6 hours.
- Weak acidotic calves that don’t suck enough
What are the 4 Qs of colostrum?
Quantity, Quality, Quickly and sQueaky clean
What are some factors affecting the quality and quantity of colostrum?
- When its collected: decreased Ig quantity over time
- Breed of cow
- Pre-partum nutrition
- Length of dry period (< 30d).
- Pre-milking.
- Abortion/induction
- Mastitis
What methods can we use to test the quality of colostrum?
- Brix refractometer (More accurate and density less temperature dependent than Colostrometer)
- Colostrometer/Hydrometer
What is the cut off for good quality colostrum when using a Brix refractometer?
Cut-off of 22% (equates to 50 g/L IgG) for good quality colostrum that can be fed as the first colostrum
If it is below this it can be fed to other calves
Describe how a Colostrometer tests the quality of colostrum
Testing the density of the colostrum
The more fat and protein, the denser it is
The denser it is the better the quality
What is the target of feeding colostrum?
Target is to provide >150 g IgG
Colostrum commonly varies from 20 to 80 g/L
Feed a minimum of 5-10% of body weight (~2-3 L) at each colostral feeding.
How long after birth should colostrum be fed?
Feed first within two hours of birth and again within 6 to 12 hours of birth.
After the first two feedings, continue to feed colostrum from later milking and of lower quality for its nutritional value.
How can the risk of GI infection in calves be reduced?
By feeding transmission milk (milk from very recently calved cows) for 5-7 days as it still contains for Igs
At what age are calves weaned?
8-12 weeks
Which Igs decline rapidly over the first week?
IgA and IgM
Which Ig declines slower over a few weeks?
IgG
There is an increased risk of … during weaning
Pneumonia
