Agricultural Sciences Grade 12 Paper 1 NSC November 2012 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 12 AGRICULTURAL SCIENCES P1 NOVEMBER 2012 MEMORANDUM MARKS: 150 This memorandum consists of 10 pages. Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 2 DBE/November 2012 NSC – Memorandum SECTION A QUESTION 1.1 QUESTION 1.3 1.1.1 A B C  1.3.1 Vitamin D/Calciferol 1.1.2 A B  D 1.3.2 Papillae 1.1.3  B C D D 1.3.3 Pelleting/granulation 1.1.4 A  C 1.1.5 A  C D 1.3.4 Pistolette/insemination gun/pipette 1.1.6 A  C D 1.3.5 Isolation/quarantine/ separation/removal 1.1.7  B C D (5 x 2) (10) 1.1.8 A  C D 1.1.9 A B C  QUESTION 1.4 1.1.10 A C C  1.4.1 rumen/forestomachs/ reticulum/reticulo- (10 x 2) (20) rumen/large stomach QUESTION 1.2 1.4.2 maintenance 1.4.3 di-oestrus A only B only A and B None 1.4.4 antibodies/immunoglobulin 1.2.1  1.4.5 anaemia 1.2.2  (5 x 1) (5) 1.2.3  1.2.4  1.2.5  (5 x 2) (10) TOTAL SECTION A: 45 Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 3 DBE/November 2012 NSC – Memorandum SECTION B QUESTION 2: ANIMAL NUTRITION 2.1 The digestive system of ruminants 2.1.1 THREE labelled parts A /reticulum/honeycomb/net stomach B /rumen/large stomach F/omasum/leaf stomach (3) 2.1.2 TWO ideal conditions for microbial activity • suitable/optimal/moderate/favourable temperature/ ≤ 38 ˚C to 42 ˚C • sufficient mineral nutrients/phosphorus/cobalt • sufficient nitrogen • easily digestible carbohydrates • a slightly acid medium/suitable pH(5,5 to 6,5) • moist • anaerobic • regular intake of food/nutrients • removal of waste products (Any 2) (2) 2.1.3 TWO functions of micro-organisms in the digestive system of ruminants • digest cellulose/crude fibre into volatile fatty acids and gases • synthesise amino acids from any nitrogenous substances/source • hydrolyse proteins from the feed to form amino acids • synthesis of vitamins(vitamin K and B-complex) (Any 2) (2) 2.1.4 A reason for enzymatic digestion in stomach Secretes digestive (gastric) juice OR Secretes enzymes responsible for enzymatic digestion (2) 2.1.5 Adapted part in a fowl Proventriculus/glandular stomach (1) 2.2 Cross section of a villus 2.2.1 Small intestines/duodenum/ileum/jejunum (1) 2.2.2 Main nutrients absorbed A – absorption of digested carbohydrates/glucose/digested proteins/amino acids/vitamins/minerals B – absorption of digested fats/fatty acids/glycerol (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 4 DBE/November 2012 NSC – Memorandum 2.2.3 Suitability of villus for its function • The villus has numerous microvilli that increase the absorption surface/large surface area • It also contains blood capillaries and the lacteal for absorption of digested nutrients • It allows constant mixing motion necessary for absorption It has a single layer of epithelial tissue  (Any 2) (2) 2.3 Supplements 2.3.1 Season for supplementing and reason • Winter/dry season • Green fodder (grass) that contain pigment (carotene) that can be transformed to vitamin A is not available in winter/dry season hence it is advisable to supplement this vitamin during winter (2) 2.3.2 TWO methods of supplementing • Injection • Dosing/drenching • Feed concentrates/rations • Drinking water • Mineral licks (Any 2) (2) 2.4 Digestibility coefficient 2.4.1 Dry material intake (kg) – Dry material of manure (kg) 100 Dry material intake (kg) X 1 = (30 kg – 10/100 x 30 kg)  – (16 kg – 35/100 x 16 kg)  100 (30 kg – 10/100 x 30 kg) X 1 OR = 27 kg – 10,4 kg 100 27 kg X 1 OR = 16,6 kg 100 27 kg X 1 = 61,48% or 61,5% or 61% (Any 5) (5) 2.4.2 Factor determining digestibility The higher the quantity/volume of feed taken in, the lesser the time for digestion/the lower the digestibility/less time of contact with digestive enzymes (2) 2.5 Nutritive ratio 2.5.1 75% – 20% = 55% (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 5 DBE/November 2012 NSC – Memorandum 2.5.2 NR = 1: % digestible non-nitrogen substances % digestible protein or 1: 75% – 20% 20% or 1: 55% 20% (2) 1 : 2,75 or 1 : 3 2.6 Pearson square 2.6.1 Feed A: 14 5 16 Feed B: 21 2 Mix 5 part s of feed A with 2 parts of feed B or 5 : 2  (3) 2.6.2 Feed B = 2 x 100 7 1 = 28,57% or 28,6% or 29% (3) [35] QUESTION 3: ANIMAL PRODUCTION 3.1 Animal shelter 3.1.1 Production system • Extensive farming Reason • Exposure to adverse weather conditions (cold, wet and windy)  OR • Farmers did not have shelter for Angora goats and were subsidised to build one (3) 3.1.2 Reasons for the recommendations by the extension officer for the production system (a) Shelter • Has sides for protection against cold winds/will reduce the wind chill • Has a roof for protection against rain • Has an enclosed area that keeps heat within/insulation (Any 1) (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 6 DBE/November 2012 NSC – Memorandum (b) Insulation material • Heat can be retained/protection against bitter cold for a longer period of time (2) (c) Heaters Assist in increasing and maintaining/regulating temperature/reduce temperature fluctuations (2) 3.1.3 Reasons for the government grant/funding • Help the farmers to build/purchase high tech equipment • To prevent job losses on the farms • To ensure that foreign exchange is earned/economic stability • To prevent shortage/losses of meat and mohair/to ensure sustainability (Any 2) (2) 3.2 Farm animals and products 3.2.1 TWO primary products of farm animals • Milk • Meat(beef/fish/pork/bacon/chicken/mutton) • Eggs • Honey • Wool  • Hides (Any 2) (2) 3.2.2 Optimising poultry production (a) Space requirements • Not overcrowded/enough space/eliminate competition • Housing/production system • Sufficient light • Fresh air/good ventilation • Cleanliness • Constant optimal temperature (Any 2) (2) (b) Feeding facilities • Functional feeding facility/allows for easy feeding/refilling • Provision of clean water and feeds/access to water • Feed accessible to animal/easy for animal to reach feed • Limits wastage (Any 2) (2) 3.2.3 Handling • Farm animal B – Bigger/higher gates and fences/sides • These facilities are more expensive • More sophisticated handling facilities required/stronger structures needed (cables/bigger poles/pipes) (Any 2) • Farm animal D – small/less structures needed/easier to handle Structures not so high/not so strong/normal fences • These facilities are less expensive (Any 2) (4) Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 7 DBE/November 2012 NSC – Memorandum 3.3 Animal behaviour 3.3.1 TWO behavioural patterns of cattle • Nervous • Wild/aggressive • Stressed (Any 2) (2) 3.3.2 TWO economic benefits of good cattle management • Better performance/production (better feed conversion ratio) • Improved reproduction rate • Improved health condition • Improved growth rate • Good quality carcass/milk/hides  (Any 2) (2) 3.4 Animal fat content research 3.4.1 • Improve the carcass quality • Higher prices for their product/higher income • Meat becomes lean/most consumers prefer lean meat (lean meat is healthier) (Any 2) (2) 3.4.2 Total fat content over a period of 50 years 30 25 Total fat content (g/100 g) 20 15 10 05 1960 1970 1980 1990 2000 2010 Years Time (years) Marking graph with the following checklist: Criteria Yes: 1 Mark No: 0 Mark 1. Line graph 1 2. X-axis correctly labelled 1 3. Y-axis correctly labelled 1 4. Points are plotted correctly 1 5. Correct heading 1 6. Units are indicated on both axes 1 (6) 3.4.3 • Fat content decreased • Fat content changed from 30 g/100 g to 5 g/100 g • An even decrease/rate of decrease was constant (Any 1) (2) [35] Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 8 DBE/November 2012 NSC – Memorandum QUESTION 4: ANIMAL REPRODUCTION, PROTECTION AND CONTROL 4.1 Reproductive organs of a bull 4.1.1 Reproductive parts A – Seminal vesicle/vesicular gland B – Prostate gland C – Cowper/bulbo-urethral gland H – Testis (4) 4.1.2 Process that occurs in K Spermatogenesis/ sperm formation/gametogenesis (1) 4.1.3 Functions D - Transports spermatozoa/enhances ejaculation L - Facilitates penetration of ovum/releases an enzyme (hyaluronidase) that allows spermatozoa to penetrate the ovum/acrosome reaction (2) 4.1.4 Influence of congenital defects • Negatively affects sperm formation/spermatogenesis/will not allow optimum spermatogenesis to take place/sperm defects (2) 4.1.5 Reason for part H to be situated outside the abdominal cavity Sperm production occurs at the temperature slightly (1 to 3˚C) lower than that of the body/to regulate the temperature for more effective spermatogenesis (1) 4.2 Progesterone and oestrogen 4.2.1 Day 7 & day 17 (2) 4.2.2 30 – 33 units  (1) 4.2.3 Progesterone Sharp increase in the level of progesterone Sharp decrease in levels of oestrogen (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 9 DBE/November 2012 NSC – Memorandum 4.2.4 TWO effects of oestrogen on the animal at peak period • Thickens the lining of the uterus prepares the uterus for the implantation of the fertilised ovum/increases blood supply to the uterus • Relaxes the muscles of the cervix • Delays the secretion of FSH at the end of oestrus • Stimulates the gland in the brain to release LH • Stimulates the process of ovulation through the release of LH • Leads to the display of signs of oestrus • Prevents bacterial infection of the uterus (Any 2) (2) 4.2.5 The corpus luteum will degenerate/burst/be resorbed/be broken down (1) 4.3 Ticks as animal parasites 4.3.1 TWO economic significance of ticks • Transmit diseases/entry point of pathogens • Production losses/skin damage  • Underperformance of farm animals • Loss of teat function/ear lobes/tail tips • Death of farm animals (Any 2) (2) 4.3.2 Three-host tick Reason: Completes every stage of its life cycle on three different hosts (2) 4.3.3 Reason for tick outbreak in the coastal region Humid and favourable climatic conditions (2) 4.3.4 Fly specie attacking sheep • Blowfly (1) 4.3.5 Biological ways of controlling ticks • Providing herbs • Use of natural enemies/predators (ox-pecker) • Breeding adaptable animals (Any 2) (2) 4.4 Sheep vaccination plan (1) 4.4.1 Weaners (1) 4.4.2 3–5 months  4.4.3 Protects the ewes at critical and delicate stage of gestation against the enzootic abortion (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Agricultural Sciences/P1 10 DBE/November 2012 NSC – Memorandum 4.4.4 Role of the state (a) Quarantine services: • To prevent diseases or pests being brought into the country • Strict import control measures are adopted/impose control measures on proclaimed diseases/ use law enforcement agencies (statutory measures, state vets stock inspectors) to control the movement of animals  (2) (b) Veterinary research: • To develop better methods to diagnose and control diseases • Train veterinarians • Operate research stations • Stock inspectors • Extension services (Any 2) (2) [35] TOTAL SECTION B: 105 GRAND TOTAL: 150 Copyright reserved