Nutrition in Pregnancy

Question 1

Why is moisture in feed important?

Answer 1

Affects palatability

Question 2

How man MJ of energy are required to make 1L of milk?

Answer 2

5MJ/L

Question 3

Energy requirements for a pregnant cow?

Answer 3

Month 2 = 0.5MJ/day
Month 4 = 1.6MJ/day
Month 6 = 5MJ/day
Full term = 35MJ/day
Overdue = 44MJ/day

Question 4

How much does weight loss contribute to energy requirement in cows?

Answer 4

Loss of 1KG/day contributed 35MJ

Question 5

What is the main source of energy for cows?

Answer 5

Cereals

Question 6

ME of grass silage?

Answer 6

10-11 MJ/kg dry matter

Question 7

What are the sources of moderate energy for a cow?

Answer 7

TMR
Maize silage
Haylage
Good pasture 
Good hay

Question 8

How is VFI affected around calving?

Answer 8

Greatly reduced

Question 9

What is the gestation period of a ewe? Do changes need to be made to the feed? What affects pregnancy rates?

Answer 9

144days (20wks)
No abrupt changes, however ewe lambs and ewes which have had one lamb previously will still be growing so should be in a separate group to receive supplementary feed.
Kale and rape may reduce fertility

Question 10

When can you make a pregnancy diagnosis in sheep?

What is an important factor with regards to feeding during pregnancy?

Answer 10

From 40 days gestation however diagnosis is often made by ultrasound at 11-15 weeks

Important to know number of foetuses

Question 11

How does supplementary feed vary depending on the weight of a pregnant ewe?

Answer 11

Heavier ewes means more supplementary feed should be given as lambs will be larger

Question 12

What are six basic considerations with regards to feeding sheep?

Answer 12

1. Too much concentrates will cause acidosis
2. VFI of the sheep is limited and may not be able to eat all food given
3. VFI is reduced around lambing
4. How much is actually being fed may not equal how much is eaten
5. Need to monitor BCS to check feed is right
6. After lambing need to monitor the feed depedning on lambs/milk production

Question 13

How can you treat pregnancy toxaemia in ewes?

Answer 13

1. Reduce energy demand
   - Induce abortion
2. Provide an energy source
   - IV glucose
   - Oral propylene glycol
   - Oral electrolyte carbohydrate source

Question 14

What is the difference between changes in BCS for diary and beef cattle?

Answer 14

Diary cattle should vary as little as possible whereas beef cattle should be decreased by no more than 0.5

Question 15

What is fat cow syndrome?

Answer 15

An excessive amount of fat storage in the liver. Around calving there is a normal tendency for fat mobilisation due to hormonal influences causing an increase in NEFAs and storage of fat in the liver, “fatty liver”.

Question 16

What are the clinical effects of fatty liver?

Answer 16

Immunosuppresion
RFMs
Endometritis
Infertility
Ketosis
Mastitis

Question 17

What are the clinical effects of fat cow syndrome?

Answer 17

Recumbency
Inappetance
Poor prognosis
Life threatening to cows

Question 18

What are the risk factors for fat cow syndrome?

Answer 18

Fat dry cows:

• More likely to already have fatty liver
• When put on diet will mobilise a lot of fat, bad idea in dry period
• At calving will have lower appetite so will mobilise fat

Normal cows:

• Sudden change in diet so the rumen can not adjust quickly enough
• Cow losing excessive weight during the postpartum period so cannot keep up with the NEB

Question 19

What is a transition diet?

Answer 19

Over a two week period before calving slowly introduce a diet with more metabolisable energy, but try to keep it with the same components to prevent rumen maladjustment

Question 20

What are the two different types of protein?

Answer 20

Rumen degradable protein forming ammonia, energy and carbon fragments. Too much protein or not enough will increase blood urea which can affect fertility

Rumen non-degradable protein which is broken down in the abomasum, either formalin treated protein or fish meal however this is more expensive

Question 21

What is an important alteration in minerals for the cow?

Answer 21

Low calcium during the dry period and high calcium during lactation so metabolic pathway is not suppressed by a large amount of calcium when it is not required during the dry period