FAC40: Energy Balance Disorders in Ruminants

Question 1

What are the energy deficiency syndromes in cattle (from least severe to most severe)?

Answer 1

Fatty liver syndrome > subclinical ketosis > clinical ketosis > chronic ketosis >fat cow syndrome

Question 2

What is the cause of fatty liver syndrome?

Answer 2

Farry infiltration of the liver usually due to excessive fat mobilisation in early lactation

Question 3

What issues are caused by fatty liver syndrome?

Answer 3

Increased incidence of metabolic disease, poor fertility, depressed milk production

Question 4

What is another name for ketosis?

Answer 4

Acetonaemia

Question 5

What is ketosis?

Answer 5

Impaired metabolism of carbohydrates and VFAs

Question 6

When does ketosis usually occur and why?

Answer 6

Occurs in early lactation because there is a large energy supply required by mammary glands in early lactation for milk production

Question 7

Describe how a high-yielding dairy cow gets to ketosis.

Answer 7

• Negative energy balance due to demands of udder
• Shortage of oxaloacetate for use in TCA cycle
• Mobilisation of fat reserves
• Metabolic pathways lead to the production of ketone bodies (acetoacetate, B-hydroxybutyrate, acetone)

Question 8

Simple describe the aetiology of ketosis.

Answer 8

Reduced appetite, starvation, or high production leads to inadequate energy supply leading to ketosis

Question 9

What are the risk factors for ketosis?

Answer 9

• Inadequate energy content of the ration (Type 1)
• Inadequate intake of the diet
• Poor utilisation of the diet
• Ketogenic foods (butyric silage)
• Poor transition cow nutrition (type 2)
• Secondary to other disease

Question 10

What are the different forms of ketosis?

Answer 10

Wasting form

Nervous form (hypoglycaemic encephalopathy)

Question 11

How do you diagnose ketosis?

Answer 11

Smell of ketone bodies on cow’s breath

Clinical biochem

• Lowered blood glucose levels
• Mobilisation of body fat - elevated NEFA
• Ketone body formation - elevated BHBA

Question 12

What is Rothera’s Test?

Answer 12

It is a Cowside test for ketosis where you test the milk (positive milk turns pink or purple)

Question 13

When you are treating ketosis, what are your goals?

Answer 13

• Restore blood glucose levels
• Replenish oxaloacetate levels
• Increase dietary gluconeogenic precursors (propionate)
• Correct predisposing factors

Question 14

How do you restore the blood glucose levels when treating ketosis?

Answer 14

400 ml of 40% glucose solution IV

Question 15

How do you replenish glucose precursors when treating ketosis?

Answer 15

Oral administration

• Propylene glycol
• Propylene glycol +cobalt
• Sodium propionate
• Glycerol (but ketogenic)

Question 16

What hormonal therapy can you give to treat ketosis?

Answer 16

Glucocorticoids like dexamethasone, betamethasone to stimulate gluconeogenesis

Question 17

What other therapies are a good idea to treat ketosis with?

Answer 17

VitB12/cobalt preparations because they are required for metabolism of proprionate

Question 18

Besides the development of ketosis, why is negative energy balance in early lactation a problem?

Answer 18

• Reduce milk production
• Reduced milk quality
• Increased incidence of clinical disease
• Reduced fertility
• Immunosuppression

Question 19

What is fat cow syndrome?

Answer 19

An exacerbation of ketosis that has a high mortality

Question 20

What are common reasons for sub-optimal energy intakes?

Answer 20

• Management of high yielding cows on summer grazing
• Overestimation of the values of autumn grass
• Overestimation of forage quality
• Overestimation of dry matter intakes

Question 21

How do you prevent subclinical ketosis?

Answer 21

Good dry cow management

Suitable milking cow ration

Use of monensin

Maximise dry matter intake

Good nutritional management

Ensure cow comfort

Question 22

What is monensin?

Answer 22

Alters micorbial fermentation in rumen to favour proprionate production

Question 23

When do you usually come across pregnancy toxaemia?

Answer 23

Last month of pregnancy

Question 24

What causes pregnancy toxaemia?

Answer 24

The rapid growth of the foetus in late pregnancy results in a marked increase in glucose requirements of the gravid uterus