Leaving Certificate Agricultural Science Sheep 1 Learning Outcomes

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Leaving Certificate Agricultural Science Sheep - 1

Leaving Certificate Agricultural Science Sheep - 1

Learning Outcomes. . . In this unit you will learn about. . . •

Learning Outcomes. . . In this unit you will learn about. . . • • • • Breeds of Sheep and their characteristics. Dental Formula. Target weights. Gestation Period and Oestrous cycle (duration & length). Ram & Ewe Selection. Mixed Grazing. Creep Feeding. Breeding Management Programme- Flushing & Sponging Management of the pregnant ewe. Management of lamb from birth to slaughter. Sheep Dipping and shearing. Sheep Housing. Wool.

Sheep Facts Lamb weighs • 3 – 5 kg at birth • 30 -40

Sheep Facts Lamb weighs • 3 – 5 kg at birth • 30 -40 kg at slaughter Gestation period 149 days (5 Months) Oestrous cycle 17 days Duration of oestrous 36 hours Ruminant Phylum Chordata Even Toe Ungulates

DENTAL FORMULA- Sheep Incisors, Canines, Premolars, Molars. 0033 4033 X 2

DENTAL FORMULA- Sheep Incisors, Canines, Premolars, Molars. 0033 4033 X 2

Mixed Grazing of Cattle & Sheep Growth rates increase by 10 -15% Tillering- a

Mixed Grazing of Cattle & Sheep Growth rates increase by 10 -15% Tillering- a denser sward & increased DM production Flush of grass around dung is ate by sheep. This is unpalatable to cattle. Even recycling of nutrients

Learning Check. . . 1. 2. 3. 4. 5. 6. State the length and

Learning Check. . . 1. 2. 3. 4. 5. 6. State the length and duration of the oestrous cycle. What is length of gestation? Name the phylum that sheep belong to. State the dental formula foe a sheep. What is mixed farming? Give the advantages of mixed grazing.

Breeds Mountain & Lowland Breeds. Wool/Lamb/Ewe Production Degree of prolificy – 1, 2, 3

Breeds Mountain & Lowland Breeds. Wool/Lamb/Ewe Production Degree of prolificy – 1, 2, 3 Growth rate & Conformation • Blackface Mountain • Wicklow Cheviot • Galway • Suffolk Down • The Belclare Improver

Breeds- Classification Prolific breeds- Belclare Improver Carcass breeds- Suffolk, Texel Cross breeds: Ewe breeds-

Breeds- Classification Prolific breeds- Belclare Improver Carcass breeds- Suffolk, Texel Cross breeds: Ewe breeds- Galway, Blackface Mountain and Cheviot.

Blackface Mountain Breed Ewe Breed Small & Hardy Able to withstand mountain conditions Horned

Blackface Mountain Breed Ewe Breed Small & Hardy Able to withstand mountain conditions Horned Wool & breeding ewes Become prolific if crossed appropriately. Mountains over 350 m Kerry, Galway, Donegal, etc

Wicklow Cheviot Mountain Breed Small Not as hardy as blackface Able to withstand mountain

Wicklow Cheviot Mountain Breed Small Not as hardy as blackface Able to withstand mountain conditions Wool & breeding ewes for lowland fattening. Mountains Wicklow, Carlow, Kildare, Wexford

Galway Lowland Native breed Live in a less severe environment Big & Late maturing

Galway Lowland Native breed Live in a less severe environment Big & Late maturing Wool, Fat lambs & hogget mutton & breeding ewes

Suffolk 12

Suffolk 12

The Belclare Improver Cross between Galway & Finnish Landrace –to improve prolificy X &

The Belclare Improver Cross between Galway & Finnish Landrace –to improve prolificy X & Llynn –to improve conformation

Learning check. . . 1. Name 3 categories of breeds. 2. Name 4 breeds.

Learning check. . . 1. Name 3 categories of breeds. 2. Name 4 breeds. 3. Give their characteristics.

Breeding Strategy If flock is inadequate or poor quality –Replace either ewes or RAMS-

Breeding Strategy If flock is inadequate or poor quality –Replace either ewes or RAMS- Cheaper to replace 1 RAM = 50 Ewes naturally 1 RAM = 8/10 ewes Synchronisation

Selecting Breeds Good Carcass Good Conformation Good prolificy. Wool/ewes/meat Feed: fertility is increased with

Selecting Breeds Good Carcass Good Conformation Good prolificy. Wool/ewes/meat Feed: fertility is increased with high quality feed

Ewe & Ram Selection EWE Good Conformation Good General Health Daughter of Prolific Mother

Ewe & Ram Selection EWE Good Conformation Good General Health Daughter of Prolific Mother Free from hereditary defects Good Feet RAM Good Conformation Good General Health Performance Tested by dept. Very Good Feet

RAM Selection Pure breed If ram has been used the previous year and ewe

RAM Selection Pure breed If ram has been used the previous year and ewe labs retained –Ram has to go!!!!! Insure not Sterile, Ram reaches puberty at 6 months

Ram for Quality Ram is half the flock. • • Growth rate Conformation Killing

Ram for Quality Ram is half the flock. • • Growth rate Conformation Killing out % Leaness All are determined by the RAM breed (purebred/pedigree) Pedigree Texel Ram realised 220, 000 Guineas Sept 2009

Ewe for Quantity Ewe should be prolific Good mothering qualities. Flushing of ewe increases

Ewe for Quantity Ewe should be prolific Good mothering qualities. Flushing of ewe increases number of lambs. Reproductive efficiency. Belclare Improver

Time to replace ewe if: Old. Not prolific. Udder troubles (mastitis) Faulty teeth. Under

Time to replace ewe if: Old. Not prolific. Udder troubles (mastitis) Faulty teeth. Under size. Lambing difficulties. Low milk yield. Barren. Bad feet.

Learning Check. . List 5 factors to be considered when selecting breeds. Name the

Learning Check. . List 5 factors to be considered when selecting breeds. Name the factors when selecting ewes and rams. Consider the comment that “rams are for quality and ewes are for quantity”. When is it time to consider replacing the ewe?

Gestation Seasonally Polyoestrous Oestrous Sept-Feb Length 17 days Duration 36 hours Gestation Period 149

Gestation Seasonally Polyoestrous Oestrous Sept-Feb Length 17 days Duration 36 hours Gestation Period 149 days (5 Months)

Oestrous cycle Sheep are seasonally polyoestrous. • This means they come into oestrous repeatedly

Oestrous cycle Sheep are seasonally polyoestrous. • This means they come into oestrous repeatedly but only over a certain period or season of the year. • This period is from early September to February • The length of oestrous is 17 days • The average duration of oestrous is 36 hours

Oestrous cycle The declining light levels in September act on pituitary gland. This stimulates

Oestrous cycle The declining light levels in September act on pituitary gland. This stimulates Follicle stimulating hormone (FSH) This in turn stimulates the ovaries to produce oestrogen This begins the oestrous cycle.

Preparing Stock For Mating Ewes should be in good condition – Condition Score =

Preparing Stock For Mating Ewes should be in good condition – Condition Score = 3. 5 -4. 0 High Conception rate results Technique = Flushing Moving sheep onto rich pastures 2 weeks prior to mating

Before Mating Two weeks before mating the sheep should receive their winter dip (not

Before Mating Two weeks before mating the sheep should receive their winter dip (not before 15 th September) Otherwise the sheep can receive the dip a few weeks after mating. The whole flock should be dosed for intestinal parasites (worms). The wool around the tail should be trimmed to facilitate service and avoid injury to the ram.

Flushing Ewes are stocked heavily on bare pastures 25/30/ha before weaning & mating A

Flushing Ewes are stocked heavily on bare pastures 25/30/ha before weaning & mating A couple of weeks before mating nutrition is improved by stocking them less heavily 15/18/ha More eggs released at ovulation (twins) More regular heat periods Higher conception rates Better attachment to uterus

Mating Ewe: ram 1: 40 Ewe: ram 1: 10 Rams must be kept away

Mating Ewe: ram 1: 40 Ewe: ram 1: 10 Rams must be kept away as they will fight Dates kept = lambing date Marker dye –every 17 days- Raddled Ear tagged 6 -8 wks- all should be in lamb Suspect ram-cull

Breeding out of season This is a technique used to induce ewes to lamb

Breeding out of season This is a technique used to induce ewes to lamb early enough for the lambs to be ready for the Easter market Prices are highest at this time Lambs born from September/October matings will not be ready for the easter market. Ewes must be brought into oestrous out of season, in July or August.

Breeding out of season This involves placement of the progesteroneimpregnated sponges. When the sponge

Breeding out of season This involves placement of the progesteroneimpregnated sponges. When the sponge is removed a single intramuscular injection of pregnant mares serum gonadotrophin (PMSG) is administered to the sheep.

Sponging Ewes are introduced to the ram in early Sept. for 8 weeks Heat

Sponging Ewes are introduced to the ram in early Sept. for 8 weeks Heat & served at different times- lambing protracted Oestrous can be synchronised. Shorter mating & lambing periods Sponges are impregnated with progesterone into the ewes vagina & left their for 12 – 16 days. The progesterone blocks the oestrous cycle If sponges are removed simultaneously all ewes come in oestrus 2 days later & are all mated together All lambs born same time (not protracted)

Raddling Harness Detects mating behaviour in rams. Helps predict lambing date. Aids in detecting

Raddling Harness Detects mating behaviour in rams. Helps predict lambing date. Aids in detecting infertile ewes which is therefore useful for culling. Also identifies infertile ram. (if all ewes show 3 different colours). Colour changes every 17 days.

Learning Check. . Explain the following terms: 1. 2. 3. 4. 2. 3. Synchronisation.

Learning Check. . Explain the following terms: 1. 2. 3. 4. 2. 3. Synchronisation. Flushing Sponging Breeding out of season. Outline the steps involved in preparing the flock for mating. What is a raddling harness?