LET'S ANALYSE AND EVALUATE
(a)
(b)
SING
DATING
1. Compare the teeth of animal (a) and animal (b). Write two points of differences.
2. Evaluate which of the two is better suited for a cow. Justify your answer giving one reason.
Answers
After studying this unit you should know:
1 What are the animal groups.
2 What is the rumen.
3 What makes the ruminant different.
4 Why animals chew the cud (ruminate).
Who eats what
Animals are divided into three groups:
· Carnivores which eat meat,
e.g. dog, lion
· Omnivores which eat meet end plants,
e.g. pig
· Herbivores which eat plants
e.g. cow, horse
The digestive system of omnivores and carnivores is as described in Unit 3. In herbivores the digestive system is very large because they eat large amounts of grass.
· The horse, donkey and mule are herbivores but do not chew the cud. They are non-ruminants.
· Cattle, goats, sheep and buffalo chew the cud. They are ruminants.
The rumen (stomach)
The stomach of a ruminant has four chambers. The first chamber is very large and is called the rumen. The second chamber is the reticulum (honeycomb). The third is the omasum (book) and the fourth is the abomasum (the true stomach). The ruminant chews grass and swallows and it goes into the rumen.
The rumen (stomach)
When the ruminant has finished eating, the food is brought back up and rechewed. This is called chewing the cud or rumination. If the animal stops ruminating this is a sign of ill health.
Ruminants make a lot of gas in their stomachs and belch once every minute, (unlike people they belch silently). If the belching stops the stomach swells with gas. We call this bloat or tympany (Unit 8).
Rumen movement
The rumen moves regularly and contracts about once every minute. By putting your fist on the left flank (in the hollow behind the ribs) you will be able to detect the contractions. Regular contractions are a sign of good health.
Rumen movement
Nails and wires in the rumen
Because ruminants eat quickly they can swallow objects like nails and wires with their feed. These objects can damage the rumen and can pass through the wall of the rumen into the heart and kill the animal.
You should tell your community to keep nails, wires and similar objects away from animal feed and pasture.
Unit 8: Bloat (tympany)
Bloat occurs when too much gas is produced in the rumen.
The left flank becomes distended and breathing becomes difficult.
This may happen suddenly, especially when the animal is grazing on wet pasture in the morning.
It may cause sudden death.
Learning objectives
After studying this unit you should know:
1 What is bloat (tympany).
2 What causes bloat in the ruminant.
3 How to prevent bloat.
4 How to treat the animal with bloat.
What is bloat (tympany)?
In Unit 7 you learned that the stomach of ruminant animals produces a lot of gas. The animals continually belch, once each minute, to get rid of the gas. Occasionally belching stops and gas builds up in the rumen to cause bloat.
As the gas builds up the left flank balloons out. The pain from this causes the animal to try to kick its belly or it stands with its back legs wide apart. It has difficulty in breathing.
What is bloat
The animal may be in distress for several hours but in bad cases of bloat the animal will be found lying on its side and death can occur in a few hours.
Causes of bloat
Bloat can occur when the animal grazes on lush young pasture, particularly if the pasture is wet. Some plants, e.g. clover, lucerne and alfalfa are especially dangerous in causing bloat but any fast growing plants can cause it.
Sometimes ruminants kept by the household and fed only feed such as dry bread can develop bloat.
Preventing bloat
· Avoid moving animals to wet pasture, especially first thing in the morning.
· Do not allow very hungry animals to graze a pasture. Offer dry, cut grass first before turning out to graze.
· Keep a watch on animals at pasture.
Treatment
Making the animal belch is one way of treating bloat. You can do this by:
· Massaging the distended rumen through the abdominal wall.
· Tying a stick in the mouth, crosswise like a horse's bit.
· Tickling the throat.
· Make the animal walk around for about half an hour.
If these methods fail then give a drench (drink) to the animal (see Drenching Annex 3). The drench used can be one of the following:
· Two large spoons of washing up liquid, e.g. Fairy, Lux.
· A solution of sodium bicarbonate (cooking or baking soda) and water.
· A small amount of kerosene (paraffin) in warm milk.
· A small bottle of peanut, soya or linseed oil.
· A very small amount of turpentine in either linseed oil, soya oil or peanut oil.
· Use a commercially, available medicine (see R20, Annex 1).
In severe cases the animal may not belch and it will die. In such cases puncturing the left flank with a sharp knife or trocar and cannula to release the gas is necessary, it will be necessary for you to act quickly as any hesitation could lead to the death of the animal.
After studying this unit you should know:
1 What are the animal groups.
2 What is the rumen.
3 What makes the ruminant different.
4 Why animals chew the cud (ruminate).
Who eats what
Animals are divided into three groups:
· Carnivores which eat meat,
e.g. dog, lion
· Omnivores which eat meet end plants,
e.g. pig
· Herbivores which eat plants
e.g. cow, horse
The digestive system of omnivores and carnivores is as described in Unit 3. In herbivores the digestive system is very large because they eat large amounts of grass.
· The horse, donkey and mule are herbivores but do not chew the cud. They are non-ruminants.
· Cattle, goats, sheep and buffalo chew the cud. They are ruminants.
The rumen (stomach)
The stomach of a ruminant has four chambers. The first chamber is very large and is called the rumen. The second chamber is the reticulum (honeycomb). The third is the omasum (book) and the fourth is the abomasum (the true stomach). The ruminant chews grass and swallows and it goes into the rumen.
The rumen (stomach)
When the ruminant has finished eating, the food is brought back up and rechewed. This is called chewing the cud or rumination. If the animal stops ruminating this is a sign of ill health.
Ruminants make a lot of gas in their stomachs and belch once every minute, (unlike people they belch silently). If the belching stops the stomach swells with gas. We call this bloat or tympany (Unit 8).
Rumen movement
The rumen moves regularly and contracts about once every minute. By putting your fist on the left flank (in the hollow behind the ribs) you will be able to detect the contractions. Regular contractions are a sign of good health.
Rumen movement