Ag science chp 29 lamb production and husbandry

1) length of oestrous cycle

2) duration of oestrous

3) gestation period

1) 17 days

2) 36 hours

3) 147 days

Define seasonal polyoestrous

• Short day breeders

• As daylight hours decrease the pineal gland stimulates the production of melatonin

• The increase production of melatonin leads to the onset of ovulation (boost)

Define the difference between early and mid-season land production

1 Define the term flushing

The process by which ewes are moved from a low plane:( of nutrition to a high plane :)of nutrition before mating (BCS 2.5)

Give advantages of flushing

~ increased ovulation rate-more eggs being released

~ increase letter size-more twins and triplets

~ more regular oestrus cycles

~ increases conception/fertilisation rates

~ better implantation of embryos into uterine wall

2define the Ram effect

• Sudden introduction of the ram can encourage some sheep breeds to start ovulating 6 weeks early

• Ram must be separated from use from six weeks prior to mating and be at least 2 KM away

• The Ram effect can start the breeding season early and synchronise breeding without sponging and compact the lambing season

• The ram effect is ineffective if the ewes are already coming into oestrus, maiden ewes will not start their cycle unless they are the correct weight + condition

Raddle on a farm

rams are fitted with a rattle to mark ewes that have been served

• Allows farmers to calculate lambing dates

• Colour is changed every 17 days to check if ewes are repeating

• If a large number of ewes are repeating check Rams fertility

3 define sponging

• Sponging is used to synchronise the oestrous cycles of the ewes and prevent a prolonged lambing period

• Sponging involves placing progesterone impregnated sponges into the vaginas of the ewes

• Sponges are removed 12 days later, ewes receive a PMSG injection and the ewes come into oestrous 2 days later

4 improving breeding outputs in Hill sheep flocks

• lambs need to be born in December/early January to allow them to be finished in time for the high price at the Easter market

• Mating must occur in July/August

• Farmers encourage ewes to come into you oestrous in July by sponging and then injecting ewes with PMSG

How to improve breeding outputs in hill sheep flocks

1) increased pregnancy rates-improved BCS increases rate of pregnancy by 10%

2) maximise the use of crossbreeding-improved hybrid vigour more prolific litter, more saleable wether(castrated male sheep)and ram (uncastrated)lambs and more prolific ewe lambs for lowland farmers

Explain what body condition scoring is

• Ratio of lean meat to fat

• Scores range from 1 to 5

• BCS 1 extremely thin animal

• BCS 5 extremely fat animal

• Assessed animals, body fat reserves along the loin and the tail head

Explain mating to lambing

• Ram should have lost some conditioning during mating season

• Will require some extra feeding

• Flushing should continue with ewes 4 weeks after meeting to ensure that the embryos develop properly

• Since most foetal deaths occur during first 4 weeks of gestation

• At the end of flushing, ewes return to a maintenance diet and their BCS drops back down to tree

• Midgestation ewes should be rotationally grazing grass or housed

Explain late gestation and steaming up

• Steaming up is the practice of increasing the amount of concentrates being fed to sheep in late gestation in order to prevent twin lamb disease (pregnancy toxaemia)

• Should be carried out in the last 6-8 weeks prior to landing were 75% of foetal growth occurs

• Steaming up increases birth weight of lamb and ensures good milk production (colostrum) in ewe

Explain scanning

• see singles, triplets or twins or any deformities

• Vital in determining the correct feed requirements

• Identifies Baron (no baby) ewes and they are culled (killed) from the flock

• Scanning sheep 80 days after Ram joins the flock

Explain vaccinations

• Vaccinated against clostridial diseases and pasteurella

• Should be regularly foot bathed to prevent lameness from foot rot

• Don’t feed ewes too much, results in big lambs causing lambing difficulties

What is the housing like?

Clean, drought free, good ventilation, adequate floor space, straw, bedded or slats

Explain the process of lambing

• Ewes are placed in clean and disinfected lambing pens

• Ewes carrying single lamb BCS 3-3.5

• Ewes carrying twin lambs BCS 3.5-4.0

• When lambing, ewes behaviour changes, search for a spot and paw at the ground becoming restless

• Ewes given assistance should receive an injection of antibiotics

• Lambs weigh less than 5 kg when born

• Once the llama is born ewe should be allowed to lick the lamb helping bonding process

• Udder of ewe checked to ensure she’s producing colostrum for antibodies (absorb antibodies in the first 24 hours)

• Lamb should receive at least 1 L of colostrum in the first 24 hours

• Naval should be dipped in iodine, preventing infection

• Placenta disposed of it will attract predators

• Lambs born outsider at great of risk of hypothermia

• Chilled lambs should be revived by feeding a colostrum through a stomach tube and warming the lamb using an infrared lamp (injection of glucose if it’s severe)

• Lamb and ewe placed in pen together, lamb should be vaccinated then

Explain the methods of fostering

1 fostering crate

2 skinning a dead lamb

3 fostering products (spray/perfume)

4 using a dog

Explain these fostering methods

1) small pen that stops ewe from kicking or hurting the lamb, lets the lamb drink milk from the ewe, after a few days lamb smells like the ewe the ewe then acceptso the lamb as her own.

2) if ewes real lamb dies, skin is removed, skin is tied onto the foster lamb, the tail skin is left on to make it more convincing, this tricks ewe by smell and after a few days when the ewe accepts the lamb, the skin is removed

3) special sprays are used to confuse the ewes sense of smell, spray is put on the ewes nose and the foster lamb makes the ewe pink the lamb is hers

4) a dog is tied near the lambing pen, this makes the ewe more protective and helps her bond with and protect the foster lamb

How can high mortality be reduced for ewe and lamb?

• adequate supervision at lambing

• Good hygiene clean dry straw

• Ensure a strong bond developed by ewe licking and allowing lamb to feed

• Checking udders of ewes for colostrum

• Ensure lamb gets enough colostrum and milk

What does an increased mortality rate mean?

• Poor hygiene, dirty wet lambing pens

• Lambing outdoors increases risk of lambs getting hypothermia and predators

• Starvation and Mismothering- ewe fails to own and care for her lamb not allowing lamb to suckle

• Lamb is not receiving enough colostrum

• Ewes steamed up to prevent to lamb disease

Describe the process of post lambing

1. ewes kept on high plane of nutrition, ensuring good milk

2. No need to continue feeding concentrate once grass is available

3. Watch out for grass tetany (deficiency of magnesium)

4. Ewes provided with a mineral lick/cal mag dusted on meal

5. Lambs produced for Easter bumped up with concentrates until they reached their slaughter weight and sold off (35-40kg)

6. Creep gates/creep feeders allowed the lambs access to grass and concentrate but not ewes

7. Weaning-months of June and July ewes and lambs are separated from each other

8. Ewes put onto crap grass to dry off in prep for flu flushing aiming for a BCS of 3.5

10. Ewes should be checked for chronic health problems e.g Mastitis, foot rot lame ewes, laming difficulties, BCS not improving, non-functioning udders and prone to twin lamb disease

General husbandry name seven types

1. Docking

2. Dagging

3. Foot bath

4. Castration

5. Shearing

6. Tagging and traceability

7. Dipping

1-Docking

• Remove part of the lamb’s tail to prevent buildup of faeces and reduce fly strike

• Done by using a rubber band applied using an elastrator this cuts off the blood supply + the tail falls off in 7-10 days carried out 1st week of lamb‘s life

  
  

2-dagging

• Removal of wall around the tail of the sheep

• Intestitial worms can cause diarrhoea causes faeces around the tail

• Blue bottle flies lay eggs in the soiled wool and causes maggots to hatch and feed off flesh of the animal. This is to prevent fly strike

3-foot bath

• Foot trimming and pairing are done to prevent lameness it is carried out to treat foot rot

4-castration

• Isn’t necessary if RAM lambs are going for a slaughter before six months (they reach puberty)

• And elastrator is used to castrate Rams

5- shearing

• Removal of wall in June prevents the sheep from overheating and in the summer it prevents fly strike

• Wall is complex protein excellent insulator two types woolen/worsted

• Wollen-short wool fibres (blankets)

• Worsted-long wool fibres (good clothes)

6-tagging and traceability

• Farmer must register their flock for dispatch and movement documentation and record an annual sheep census

7-dipping

• Sheep are dipped twice yearly in solution of water and copper sulphate to prevent fly strike in summer and mange mite (sheep scab) in winter

• Sheep dipped for one minute with head immersed twice

• Done on a dry day to prevent rain diluting solution

Name seven diseases in sheep

1. Twin lamb disease

2. Milk fever

3. Grass tetany

4. Clostridial disease

5. Fly strike

6. Sheep scab

7. Navel ill or joint ill

Explain what each of these diseases are

1. A breakdown of fat reserves in ewes body leading to liver failure

2. A deficiency of calcium

3. Deficiency of magnesium in spring grass

4. Caused by clostridium bacteria

5. Blue bottle flies lay eggs in the soiled fleece of a sheep, the maggots eat into the flesh of the sheep

6. A notable disease-man might feed on the skin and flesh of the sheep

7. A bacterial infection of the navel after birth that then spreads to joints

Give a prevention for each of these diseases

1. Steaming up

2. Feeding ewes cal mag

3. Feeding ewes cal mag

4. Vaccination

5. Dipping sheep and dosing sheep for worms

6. Dipping sheep in winter

7. Dipping the navel in iodine

What areas is the SBLAS (sustainable beef and lamb assurance scheme) target intervention

• lameness control

• Fly strike control

• Mineral supplements and meal feeding ewes post lambing

• Management of pregnant ewes (scanning)

• Mineral supplements to lambs pre-weaning

Standards required by the SBLAS include

• show competence as a herd owner and have relevant experience in training

• Have appropriate animal housing, hygiene around lambing, shearing, castration, treatments of disease, tail docking and dagging and overall general health of livestock

• Comply with regulations on purchasing use and storing animal medicines

• Show an ongoing plan about health and welfare of livestock on farm

How can farmers improve sustainability on their farms?

• improve soil health-sow multi species swords

• Land management- incorporate Clover for nitrogen fix and soil test for pH and NPK every five years

• Animal welfare-appropriate animal handling facilities to minimise stress or injury