AGRICULTURAL SCIENCES PAPER 1
GRADE 12
NSC EXAMINATIONS
MEMORANDUM
NOVEMBER 2021

SECTION A
QUESTION 1
1.1
1.1.1 B 
1.1.2 D 
1.1.3 C 
1.1.4 A 
1.1.5 B 
1.1.6 A
1.1.7 C 
1.1.8 C 
1.1.9 A 
1.1.10 C (10 x 2)
(20)

1.2
1.2.1 B only 
1.2.2 Both A and B 
1.2.3 A only 
1.2.4 None 
1.2.5 None  (5 x 2)
(10)

1.3
1.3.1 Gross energy/GE 
1.3.2 Vector 
1.3.3 Placenta retention/retained placenta 
1.3.4 Spermatogenesis 
1.3.5 Pedometer (5 x 2)
(10)

1.4
1.4.1 Vitamin A/retinol
1.4.2 Neck/head clamp/head gate 
1.4.3 Urethra 
1.4.4 Lactation
1.4.5 Impotence (5 x 1)
(5)
TOTAL SECTION A: 45

SECTION B
QUESTION 2: ANIMAL NUTRITION
2.1 Feed intake
2.1.1 Indication of the name of the animal
COLUMN A - Pig 
COLUMN B - Fowl/chicken/poultry 
2.1.2 Reason
COLUMN A

• Chemical digestion starts from the mouth through amylase 
• Ingest food using the lips and tongue 
• The teeth grind the food 
• Food is pushed down the oesophagus into the stomach where it is digested further by enzymes  (Any 1)(1)

COLUMN B

• Animal ingest food by pecking 
• Food is moistened, softened and stored 
• Physical and chemical digestion occur in stomach  (Any 1) (1)

2.1.3 Stating the structural difference in the large intestines of animals
COLUMN A - There is one caecum/blind gut/colon of the pig is long/ there is a rectum 
COLUMN B - There are two caeca/blind gut/colon of a chicken is short/no rectum 
2.2 Parts of the alimentary canal
2.2.1 Identification of the letter

1. C 
2. A 

2.2.2 TWO digestive juices deposited in small intestines

• Bile
• Pancreatic juice  (2)

2.2.3 Fat digestive enzyme secreted in pancreas
Lipase (1)
2.2.4 TWO reasons for breaking down of fat by bile

• To increase the surface area 
• Allows lipase to work better/to enhance chemical digestion 
• To improve the absorption of fatty acids/assists with the absorption of fat-soluble vitamins A,D,E,K  (Any 2) (2)

2.3 Mineral deficiency
2.3.1 Naming the mineral deficient in animal
Phosphorus/P  (1)
2.3.2 Name of the condition
Pica (1)
2.3.3 Indication of the feed
Bone meal/mineral lick  (1)
2.4 Feeds
2.4.1 Classification of feeds
Maize meal - Concentrates
Maize stalk - Roughages  (1)
2.4.2 Importance of feeding roughage in

1. Young ruminant
   Stimulate the development of rumen/fore stomach 
2. Adult ruminant
   • Normal functioning of the rumen/prevents bloating 
   • Stimulates production of butterfat in milk 
   • Supply bulkiness to the ration 
   • Provides energy for maintenance (Any 1)

2.4.3 Calculation of the ratio to which maize meal and fish meal be mixed to get a feed with 15% DP
Maize meal : Fish meal 21 : 6  OR Fishmeal : Maize meal 6 : 21  (4)
2.5 Digestibility coefficient
2.5.1 Digestibility co-efficiency
DM = 15 kg x 84% (0,84) = 12,6 kg OR ⁸⁴/₁₀₀ x 15 kg = 12,6 kg 
DC = Dry material intake (kg) – Dry mass of manure (kg) x 100 
                               Dry material intake (kg)                            1
= 12,6 kg – 3.5 kg x 100 
12,6 kg 1
= 72,2  %  (5)
2.5.2 The percentage of the excreted material
27,8% (1)
2.6 Fodder flow programme
2.6.1 The month in which to reduce the number of farm animals
June (1)
2.6.2 Reason

• Feed availability is at its lowest (100 kg/ha) 
• More supplementary feed required (8 kg/animal/day) (Any 1) (1)

2.6.3 Calculation of the total feed available for April (in tons) if 5 ha are available for grazing
800 kg/ha x 5 ha = 4 000 kg OR 800 kg/ha 
                                                     1 000 kg
= 4 000 kg  = 0,8 tons x 5 ha 
   1 000 kg
= 4 tons = 4 tons  (3)
[35]

QUESTION 3 : ANIMAL PRODUCTION, PROTECTION AND CONTROL
3.1 Heat stress in dairy cattle
3.1.1 TWO visible ways cattle use to decrease the effects of heat

• Standing under trees/shade for protection from sun 
• Standing inside the water to cool the body 
• Standing apart/away from each other  (Any 2) (2)

3.1.2 TWO importance of shelter for animals 

• Increases young animals' survival rate 
• Protects animals from predators/theft 
• Enables control of diseases and parasites 
• Provides an ideal temperature/protects animal against adverse weather conditions 
• Prevents dehydration 
• Maximize production  (Any 2) (2)

3.1.3 TWO requirements for the vehicle transporting farm animals

• Floors should not be slippery 
• Adequate ventilation 
• Rails must be high and strong 
• No sharp edges that can harm/hurt animals 
• Vehicles should be clean/hygienic 
• Must have enough space  (Any 2) (2)

3.2 The effect of environmental temperature
3.2.1 The farm product Milk  (1)
3.2.2 Description of the relationship between dry matter intake, milk yield and water intake With increased environmental temperatures dairy cows will eat less feed less milk will be produced and will drink more water (3)
3.3 Production systems
3.3.1 Identification of the production systems

1. Farmer B (1)
2. Farmer A (1)

3.3.2 Justification

1. Extensive production system It took the herd longer to reach the live weight of 550 kg/ slower growth rate(1)
2. Intensive production system It took the herd less time to reach the live weight of 550 kg/ faster growth rate (1)

3.3.3 A disadvantage in relation to input costs Input costs are high/it is expensive (1)
3.4 FMD in farm animals
3.4.1 The pathogen causing FMD
Virus (1)
3.4.2 TWO main symptoms of FMD in farm animals

• Blister-like lesions 
• Painful ulcers 
• Sticky, foamy salivation 
• Severe lameness /unable to walk/limping 
• Nasal discharge  (Any 2)(2)

3.4.3 TWO roles of state in controlling animal diseases

• Public awareness/report the outbreak of FMD 
• Quarantine services/separation/isolation of infected animals 
• Veterinarian services 
• Banning of exports  (Any 2) (2)

3.4.4 TWO economic impact of FMD

• International trade decreases/export bans 
• Reduce food security 
• Decreased production 
• Loss of income/profit/jobs 
• Costs to control, prevent and treat animals are high 
• Death of an animal/stock losses  (Any 2) (2)

3.5 Methods used to administer medication to farm animals
3.5.1 Identification of the pictures

• Picture A 
• Picture B 
• Picture D  (Any 2) (2)

3.5.2 Identification of the pictures

• Picture B 
• Picture C  (2)

3.6 Different organisms harmful to farm animals
3.6.1 Term referring to the organisms in pictures A, B, C and D
Parasites  (1)
3.6.2 Classification of the organisms

• PICTURE B - External/ecto parasite 
• PICTURE C - Internal/endo parasite  (1)

3.6.3 Identification of the letter

• Redwater - B/Blue tick 
• Rift Valley Fever (RVF) - A/mosquito 
• Heartwater - D/Bont tick 

3.7 THREE plants that are poisonous to farm animals

• Thorn apple/devil’s apple 
• Poison bulb/slangkop 
• Poison ivy 
• Maize fungus 
• Lantana camara 
• Tulip 
• Seneciosis 
• Gousiektebossie 
• Diplodiosis 
• Poison leaf/gifblaar 
• Geeldikkop 
• Gousiekte 
• Vermeersiekte (Any 3) (3)

[35]

QUESTION 4: ANIMAL REPRODUCTION
4.1 Female reproductive system
4.1.1 Identification of the TWO secondary sex organs

• B 
• C 
• D 
• E  (Any 2) (2)

4.1.2 Providing the letter

1. The site of fertilisation - B 
2. Glands secreting nutrients - C 

4.1.3 TWO functions of the cervix (Part D)

• Opens to allow semen passage to the uterus 
• Closes the uterus through the thick mucus secretion/mucus plug to prevent microbial infection of the uterus 

4.2 Hormone levels
4.2.1 Definition of the concept oestrus
The period when non-pregnant female animals  will be receptive to male animals/will allow mating  (2)
4.2.2 Indication whether the female farm animal is pregnant or not
The female animal is not pregnant  (1)
4.2.3 Reason
The animal is showing a normal oestrus cycle/the level of progesterone is decreasing/the level of oestrogen is increasing/ re-appearance of oestrus  (1)
4.2.4 Indication of the levels of FSH
FSH level will be high  (1)
4.3 Bar graph
4.3.1 Bar graph showing the fat and protein percentages from weeks 5 to 25

CRITERIA/RUBRIC/MARKING GUIDELINES

• Correct heading 
• X-axis: correct calibrations and labelled (Weeks) 
• Y-axis: correct calibrations and labelled (Fat and protein) 
• Correct unit (%) 
• Combined bar graph 
• Accuracy  (6)

4.4 Synchronisation of oestrus
4.4.1 Identification of the process
Synchronisation of oestrus  (1)
4.4.2 TWO techniques/methods to induce synchronisation of oestrus

• Prostaglandin injection 
• Synthetic progesterone/oestradiol injection 
• Gonadotropin- releasing hormone/GnRH injection 
• Vaginal insertion (CIDR) 
• MGA/PG mixed with feed (Any 2) (2)

4.4.3 TWO disadvantages of the synchronisation of oestrus

• High management inputs/skills/technology are required 
• Adequate facilities are required 
• High costs/expensive
• Labour intensive 
• Time consuming 
• Pregnancy tests must be done frequently (Any 2) (2)

4.5 Re-arrangement of the stages of mating in sequential order

• C 
• D 
• A 
• E 
• B 

4.6 Parturition
4.6.1 The stage of parturition in the diagram

• Expulsion/ejection of the foetus 
• Delivery  (Any 1) (1)

4.6.2 Term for birth difficulty
Dystocia  (1)
4.6.3 TWO problems with the calf

• Calves with high birth weights/large calves 
• Bull calves normally have higher birth weights 
• Malformed calves/congenital defects/hydrocephalus 
• Multiple births/twins 
• Incorrect position of the calf/posterior presentation  (Any 2) (2)

4.7 Multiple births
4.7.1 Identification of the type of multiple births

1. A - Identical/monozygotic twins 
2. B - Fraternal/non-identical/dizygotic twins 

4.7.2 Differentiation between
Monozygotic - Formed from the fertilisation of a single ovum 
Dizygotic - Formed from the fertilisation of two different ova  (1)
[35]
TOTAL SECTION B: 105
GRAND TOTAL: 150