Ewe Nutrition and reproduction

Question 1

Name the different periods of the production calendar

Answer 1

• Maintenance
• Breeding
• Early gestation
• Late gestation
• Early lactation
• Mid lactation
• Late lactation

Question 2

What happens during early gestation ?

Answer 2

 Slight increase in nutrient requirements
 Embryo and early foetal losses
 Placental growth

Question 3

What happens during late gestation ?

Answer 3

 Marked increase in nutrient requirements
 Maternal reserves
 Birth weight of lamb + survival

Question 4

What happens during early lactation

Answer 4

 Highest nutrient requirements

Question 5

What happens during mid lactation ?

Answer 5

 Nutrient requirements less than early lactation, but still high

Question 6

What happens during late lactation ?

Answer 6

 Nutrient requirements less than mid lactation

Question 7

What nutrients must a diet contain to enhance luteal progesterone production and thus embryo survival.

Answer 7

Diets rich in palmitic fatty acids
Diets rich in stearic fatty acids
Diets rich in oleic fatty acids
Fish oils rich in EPA and DHA fatty acids

Question 8

What nutrients suppress the synthesis of uterine prostaglandin ?

Answer 8

Linoleic acid

EPA

DHA

Question 9

Name and describe the 3 peroiods of the 21-week gestation period

Answer 9

First month:
 Maintain BCS (2.5) to minimise embryo and
early foetal losses

Month 2 and 3:
 Rapid growth of placenta, but foetal growth is small
 Prevent BW losses of more than 5%
 Placenta size is important in relation to lamb BW
 Keep BCS constant

Last 2 months
 Foetus weight increase with 85%
 Both energy and protein supply will have a linear effect of lamb BW + colostrum + early milk production
 Lamb BW directly related to lamb mortalities
 If BCS increases with 1 during late pregnancy, birth weight will increase with 0.45 kg

Question 10

What is the ideal birth weight for a lamb?

Answer 10

3.5 to 5.5 kg

Question 11

What are the reasons for pregnancy toxaemia?

Answer 11

a) Over fat ewes
b) Multiple foetuses
c) Poor quality feed / low intake
d) Short grazing times
e) Cold or wet conditions
f) Internal parasites
g) Old ewes

Question 12

Give the different names for Pregnancy disease

Answer 12

Pregnancy toxaemia
“domsiekte”
Twin-lamb disease
Ketosis
Lambing sickness

Question 13

What is the symptoms of pregnancy disease?

Answer 13

1. Isolation
2. Poor intake
3. Reluctant to move with affected coordination
4. Appears to be blind as there is no eye reflex
5. As animal weakens, she will lie down on her chest and not be able to get up again - could become slightly bloated.
6. Eventually she goes into a coma – just before she dies, a thin stream of rumen contents sometimes trickles from her nose

Question 14

How long does it take an ewe to die from pregnancy disease?

Answer 14

2 - 10 days

Question 15

What are the post-mortem signs of pregnancy disease?

Answer 15

1. Enlarged, pale tan colour, friable texture and fatty liver
2. Abdominal fat is fine white specks with a chalky appearance
3. Blood may appear to have a layer of fat floating on it
4. Usually twins in the uterus
5. Rumen has little food in it because of size of
   uterus
6. Ketone bodies in urine stain a ketone paper strip purple.

Question 16

What do we do if we are uncertain about whether an ewe has milk fever or pregnancy disease?

Answer 16

she can be given 60 – 80 ml calcium borogluconate subcutaneously

Question 17

How do we treat an ewe with pregnancy disease?

Answer 17

1. Caesarean section to remove the lambs, or with an injection to start labour
2. 10 –50% dextrose or glucose solution can be injected into a vein to boost available energy levels
3. Sugar water or molasses can also be given by mouth in a mixture of 250g sugar or molasses to 250 – 750 ml water.
4. 115 ml Glycerine or propylene-glycerol diluted in water, by mouth twice a day will also boost energy levels.

Question 18

What is the milk conversion efficiency of a lamb?

Answer 18

± 0.167 live weight gain per kg of fresh milk intake

Question 19

How does milk fever occur in lambs?

Answer 19

Young lambs are affected by a drop in their blood calcium levels, especially after being transported for long distances. The hind legs stretch out, and the head and neck get paralyzed.

Question 20

What are the symptoms for milk fever?

Answer 20

1. Faint muscle tremors and a staggering gait
2. Sheep lies down with hind legs stretched out behind them and cannot get up again
3. There is a sticky discharge from the nose and the animal breathes with difficulty

Question 21

How do we treat milk fever?

Answer 21

1. If animal is paralyzed but still aware and eating, calcium can be injected subcutaneously
2. In advanced cases, calcium borogluconate should be injected immediately into neck vein

Question 22

How do we prevent milk fever?

Answer 22

1. Heavily pregnant ewes, and ewes feeding twins, should not be allowed to graze on lush pastures such as barley, oats or kikuyu only
2. Leguminous plants such as lucerne or clover are safe because they contain enough calcium.
3. A lick should be provided to supply calcium.
4. Feed lime (calcium carbonate) can be used, with salt and/or molasses added.
5. Each sheep should get 5 – 15 g of feed lime per day
6. Try to avoid any disturbances that could cause ewes that have lambs and pregnant ewes in their last weeks of pregnancy to get less feed than usual.
7. They should not be shorn, dipped or moved, or their grazing suddenly changed
8. Slaughter lambs should not be transported for long distances without feed and water.

Question 23

What nutritional components affects reproduction rate in ewes?

Answer 23

1. Cu
2. Co
3. Mo
4. S
5. Se - Vit E
6. Plant oestrogens