CBL 10: Wanted, Students for Lambing

What is the maximum age a lamb can legally be tail docked and/or castrated using a rubber ring in the UK?

7 days (a week)

When should an animal not be transported without consulting a vet first?

it has open wounds, is lame, signs of active disease, blindness, weakness, heavily pregnant

What age should a lamb that is reared indoors be tagged by?

within 6 months of birth

What age should a lamb that is reared outdoors be tagged by?

9 months of birth

What should you tag a lamb that is intended for slaughter with?

yellow slaughter tag

When do you choose to use a slaughter tag for a lamb?

if it’s intended for slaughter before 12 months old

Can you bury dead livestock?

NO

How should fallen stock be dealt with/disposed of?

• knacker

• hunt kennel

• maggot farm

• incinerator

• renderer

What should you NOT do to deal with fallen stock?

burn/bury stock on farm or feed stock to birds

What do you do in September regarding sheep management?

check BCS 2.5-3.5 and split ewes into groups depending on this

MOT ram, BCS rams 3.5-4

What do you do in October regarding sheep management?

put rams out with ewes for breeding

separate rams and ewes after 6-8 weeks (2 oestrus cycles)

How many days into pregnancy should you scan ewes to check how many lambs they have?

40-90 days

What is the length of the ovine oestrus cycle?

17 days

What should you focus on in February regarding sheep management?

nutritional needs of ewes (increase nutrient density)

What happens in March & April regarding sheep management?

peak lambing time, tail docking and castration, ewes and lambs out on pasture together in April

What happens in May regarding sheep management?

shearing, check BCS of ewes 2-2.5 when weaning

What happens in August in farms regarding sheep management?

sell lambs around 40kg (keep some ewes as replacements)

lambing percentage

number of lambs born per ewe

How do you calculate lambing percentage?

number of lambs born divided by number of ewes lambing (X100)

What is the national average lambing percentage?

110%

What does breeding sheep that thrive and perform on forage-based systems help?

improve sustainability

How does breeding sheep on forage-based systems help to improve sustainability?

improve soil health and reduce methane emissions

How do you perform a BCS on a sheep?

place hand over backbone & loin area behind last rib to feed amount of fat cover and muscle mass, feel for sharpness of spinous and transverse processes

What is the idea body condition of a sheep?

3 (on 1-5 scale)

Name some examples of sheep breeds suitable to living in hill systems

welsh mountain, cheviots, herdwick, swaledale

What are characteristics of hill breeds?

• thick coat

• can walk long distances

• good mothers

• can handle harsh environments

Name some examples of sheep breeds suitable to living in upland systems

Bluefaced Leicester, Border Leicester, Teeswater, Devon and Cornwall Longwool

What are the characteristics of upland breeds?

• able to cope better on lower ground

• good mothers

• more offspring than hill breeds

Name some examples of sheep breeds suitable to living in lowland systems

Texel, Suffolk, Charollais, Romney

What are the characteristics of Lowland breeds?

• grow fast

• heavy frame

• lots of offspring

What are the 2 main reasons that a purebred sheep may be crossed with another breed?

• heterosis/ hybrid vigor

• breed complementarity

What is breed complementarity?

combining desirable traits of 2 breeds into one animal

Terminal sire

large meaty sheep used to crossbreed with mule ewes to produce finished lambs for meat

Characteristics of terminal sire breeds

• excellent carcass formation

• rapid growth potential

• hardy and prolific

Name common terminal sire breeds

Suffolk, Texel, Hampshire down

What is the role of vasectomised (teaser) rams in sheep farming?

encourage ewes to come into season a week or 2 earlier than normal at the onset of the breeding season

What methods can be used to identify ewes that have been served?

raddle/harness marking, ultrasound scanning

Why is AI not routinely performed in sheep (in contrast to cattle)

cannot insert inseminating pipette same as in cattle as there’s a number of folds in cervix so lumens don’t align, makes it unreliable

How can AI be performed in sheep?

laparoscopic insemination

Why is a ewe vulnerable to the effects of stress in early pregnancy?

affects developing foetus (cortisol passes across placenta into fetus blood)

How may a ewe’s stress be avoided in early pregnancy?

limit human interaction, no sheep dogs, minimal changed to living conditions and diet

Why is it important to maintain stable BCS mid pregnancy (30-90 days)

underfeeding can reduce placental growth and fetal development

Why is ultrasound scanning important on sheep farms?

determine number of foetuses - can separate ewes depending on this and feed them accordingly

When does the majority (70%) of foetal growth occur?

late pregnancy (day 91-147)Wh

Why are replacement ewes required?

maintain and optimise a healthy and productive flock

What are the 2 possible sources of replacement ewes?

homebred or buying in

When should replacement ewes be bought in?

6-8 weeks prior to mating

What should be considered when selecting replacement ewes?

easy birth, thrive, good mothering, grow well, good body structure

Why may sheep be castrated?

avoid ram taint and reduce unwanted pregnancy

What are the commonly used methods of castration?

• banding (rubber ring or elastration)

• surgery

• clamp

• short scrotum

• immuno-castration

During banding castration where is the rubber ring placed?

around neck of scrotum

What do you use to place a rubber ring during castration?

elastrator

What does the rubber ring cause in castration of sheep?

tissues to become necrotic and shed

How many weeks after application does it take for the tissues to shed during a rubber ring castration?

4 weeks

What does obstruction to the blood supply during rubber ring castration cause a shortage of?

oxygen (needed for cellular metabolism)

What are the negatives of the rubber ring method of castration?

pain, lesions

What are the negatives of surgical castration of sheep?

pain & risk of infection, haemorrhage and prolapse of intestinal loops

What are crushed in a clamp castration?

spermatic cords

What are the benefits of clamp castration?

skin intact (lower risk of infection), reduced pain (compared with other methods)

What does immuno-castration reduce?

testicular activity

How does immuno-castration reduce testicular activity?

prevents release of GnRH

How is immuno-castration performed?

vaccine

What are the advantages of immuno-castration?

no pain

What is the negative of immuno-castration?

no licensed vaccine against GnRH currently available for sheep in UK

Why may sheep be tail docked?

prevent faecal contamination and subsequent myiasis

What are the 3 methos of tail docking in sheep?

• rubber ring/elastration

• surgical docking

• hot docking iron

What must you make sure when tail docking?

tail still covers anus or vulva

What are sheep commonly vaccinated against in UK?

• clostridial disease

• pasteurellosis

• toxoplasmosis

• footrot

When should ewes have their annual booster vaccine?

4-6 weeks pre-lambing

What can you do to monitor lameness?

prevention programme, regular and careful pairing, good stockmanship

What measures can be implemented to manage lameness?

regular treatment of infected feed

vaccinate

cull chronically lame sheep

foot-bathing

How can you monitor fly-strike

small offal-baited monitor traps

check stock daily for signs

seasonal planning

How can you prevent flystrike?

dipping

tail docking

fly traps/insecticide

crutching

Crutching

removal of wool from perineal area

How can you treat flystrike?

pour on prethyroid insecticides, shear

What is meant by ‘farm assurance scheme’?

allows farmers to demonstrate that the food they’ve produced has met specific independently certified standards at each stage of the supply chain (farm to fork)

Why is vaccination against clostridial disease and pasteurella/mannheimia recommended 4-6 weeks before lambing?

ensure adequate accumulation of immunoglobulins in colostrum

When is the vaccination against clostridial disease and pasteurella/mannheimia recommended?

4-6 weeks before lambing

What is the definitive host of toxoplasma gondii?

cats

What are the intermediate hosts of toxoplasma gondii?

birds, rodents, pigs, sheep

What is the accidental host of toxoplasma gondii?

humans

What is the route of transmission of toxoplasma gondii?

eggs passed in cat faeces, humans ingest infected meat (from intermediate host)

What are the pathogenic effects of toxoplasma gondii?

abortion in sheep/goats

What are the clinical signs of toxoplasma gondii?

fever, diarrhoea, cough, seizures and death

What is the definite host of neospora caninum?

dogs

What is the intermediate host of neospora caninum?

cattle

What is the route of transmission of neospora caninum?

eggs passed in dog faeces ingested by cattle

How can neospora caninum be transmitted from an infected cow to the fetus

transplacentally

What are the pathogenic effects of neospora caninum?

aborted/congenitally infected calf, neurological disease

What are control measures can be put in place for pregnant people to avoid abortion?

don’t help with lambing and avoid contact with lambs

Which infectious agents affecting sheep also pose a risk to pregnant women?

chlamydia abortus, listeriosis, Q fever, toxoplasmosis

Name 3 conditions associated with pregnancy that may be seen in a ewe

• pregnancy toxaemia

• prolapse

• dystocia

When does pregnancy toxaemia occur?

late gestation

What is pregnancy toxaemia caused by?

inadequate nutrition/ poor BCS

vaginal prolapse

vagina come out of vulva and can see cervix

What is vaginal prolapse more common in?

ewes having more than one lamb

dystocia

difficulty of ewe to give birth

How can you avoid dystocia?

avoid overfeeding, select rams that produce smaller lambs, monitor BCS, look out for malpresentation during lambing and assist

What is the 1st stage of parturition?

dilation of cervix

How long is the first stage of parturition (dilation of cervix)?

2-6hrs