Lambing preparation and survival Flashcards
How bad is lamb mortality?
NADIS 10-25% by day 3 - 11% dystocia - 11% stillbirth - 25% hypothermia/starvation - 14% infection - 13% non infectious disease
What is the gestation period of normal lambing?
143-147 days
What are the 3 stages of lambing?
1st stage = 3-6 hours, inc. activity, short (15-30s) abdominal contractions, build to cervical dilation, mucus hanging from vulva
2nd stage = 30-120 mins, actual lambing, active + powerful straining, amnion showed rupture, normal presentation (nose and two feet)
3rd stage = 2-4 hours, expulsion of foetal membranes, 2-3 hours after lambing
When to intervene?
1st stage over 4 hours or stopped completely
2nd stage near beyond 2 hours
Obvious malpresentation
No 2nd lamb after 30 mins
Prolonged unproductive straining (30 mins to 1 hour)
Intervention in lambing - what do i need?
Lambing snare Antibiotics (penicillin, oxytetracyclin) Analgesics (procaine, flunixin) Suture material for prolapses Respiratory stimulants Iodine navel dip Lubricant - use more than you think you need
What are common presentations of lambs?
- head + two feet, typically no assistance unless oversized
- both legs back, normal presentation, draw straight back
- Leg back, ewe on side with leg back uppermost, repulse lamb, pull leg forward, lamb as normal
- bilateral shoulder flexion, head out only, repulse lamb and bring legs forward, epidural (sacrococcygeal)
- breech, tail out, repulse, bring hind limbs to vulva, epidural
- twins presenting at the same time - identify which leg belongs to which, push one back, pull other one out, repeat
- head to side, repulse and pull head to fore, use snare to keep head up, lambs frequently dead
What are recommended medications to use at lambing time?
NSAIDS - after every intervention - some (most) farms will not have Antibiotics - check farm health plan - penicillin or oxytetracycline - use on all or some (worst) - extra epidural (sacroccygeal)
What are some common problems that ewes can encounter?
Metritis Ringwomb Vaginal prolapse Uterine prolapse Twin lamb disease Hypocalcaemia Abortion Mastitis
What is metritis?
Infection of the womb
Caused by poor lambing practice
Signs = dull ewe, poor milk yield, swollen vulva with red/brown discharge
Treat with antibiotic
What is ringwomb?
Failure of the cervix to fully dilate, 2 fingers able to get in, manually dilate
C-section
For the drugs advised there is not a lot of evidence as to whether they work effectively or not
What is a vaginal prolapse?
Pre-lambing issue, 1% but can vary
Vagina + cervix
Risk factors: over conditioned, lack of movement (housed), high fibre diet, triplets, lameness, hypocalcaemia
Signs: visual observation, straining like 1st stage of labour, isolation, reluctance to feed, cervix may be open
Treatment: first aid, clean + protect, epidural, ewe standing, lift bladder to allow urination, retain (truss/harness, plastic devices, suture), lamb ewe
What is a Buhner suture?
Veterinary intervention
Epidural mandatory
Release at lambing
What is a uterine prolapse?
0.1% of lambed ewes typically
Large single lambs predisposed
Due to pain or swelling of posterior reproductive tract
Identified by visual signs
Treatment: vet emergency, antibiotic course, NSAID, feed, water, supplement lambs
What is evisceration through a vaginal tear?
Risk factor for prolapse
1-2% of affected flocks
No treatment, euthanasia required
What is pregnancy toxaemia (metabolic diseases)?
Twin lamb disease, energy demand exceeds supply
- clinical signs - does not come to feed trough, isolated, dull + depressed, blind, head pressing, fine muscle tremors of the head, weakness & recumbency, death
- treatment - palatable feeds + fresh water, drench with propylene glycol, IV glucose injection, glucocorticoid injection
- prevention - feed to lamb number, monitor BCS up to lambing
What is hypocalcaemia (metabolic diseases)?
Milk fever, late gestation, older ewes, change in ration, stress, inappropriate mineral supplementation
- signs - depressed, weak, unable to stand, rumenal stress and bloat, reflux of ruminal contents (green), coma + death (48-72hr)
- treatment - 40ml IV calcium over 30-60s, subcut slower
What is abortion?
Should be less than 2% of the flock
Expulsion of a non viable foetus before term
Zoonotic - hygiene critical, pregnant women at risk, isolate animal, get a diagnosis
Prevention - vaccination, biosecurity
What is mastitis?
Acute = not painful, clots in milk, sick ewe, not feeding lambs
Chronic = hard, lumpy, palpable masses, decreased yield (5%)
Treatment - early treatments with NSAIDS and antibiotics
Risk factors - BCS< 3, teat lesions, udder conformation, reduce transmission, shelter, extra nutrition, test for Maedi Visna
What are risk factors associated with perinatal mortality?
- Inadequate/poor quality colostrum
- poor hygiene and weather
- lack of naval dressing and supervision
- infectious disease
- ewe condition
- birthweight
- Iodine deficiency
What should birth weights be for singles, doubles and triplets?
- single 5.5-7.0kg
- twins 5.0-6.0kg
- triplets greater than 4.0kg
- for meat breed x F1 ewe
- reduce by 1kg for hill breeds
How does a normal lambing take place?
Cleaning lambing pen will reduce prevalence of many diseases
- Amniotic sac, is it out if so leave alone for a bit, if sheeted break open and allow breathing
- Breathing, may take up to 30sec, leave to sort its self out for a few minutes, no - dopram (respiratory stimulant), rub chest, stimulate nostril
What is colostrum?
Milk produced by ewes in the first hours/days after lambing - high in fat and antibodies
Source of immunity for the new born lamb, from dam
How do you know if a lamb has had colostrum?
Beware of suckling wool
Palpate abdomen
About 30 mins after lambing
What is the recommended amount of colostrum for a lamb to have in the first 24hrs?
After 2hrs - 50ml/kg
After 24hrs - 200ml/kg
Why use a navel dressing?
Navel has direct contact with organs and its an open wound
- disinfect, prevent infection and dry navel
With what?
- 10% iodine in alcohol base “strong base”
When?
- first 15 mins and then 2-4 hours later
What are common conditions seen in lambs?
Dystocia Abortion associated pathogens Hypothermia Watery mouth Navel ill
What are abortion agents?
Biosecurity measures
- quarantine
- fencing etc.
Vaccination
What is watery mouth?
E.coli colonisation of the gut in new born lambs
Due to intensive husbandry: poor hygiene, contaminated fleece, no colostrum intake
Endotoxaemia
Common in twins but especially triplet lambs aged 12-36 hours
Signs: dull, lethargic, depressed and reluctant to suckle, profuse salivation, wet lower jaw, increased abdominal distention although the lamb has not been sucking
Treatments: soapy water enemas, mild laxatives and purgatives, oral antibiotics effective during the early stage, oral and electrolyte therapy (50ml/kg) 4x a day, penicillin type drug injected intramuscularly
How to prevent watery mouth?
Abundant clean dry straw bedding, use of para-formaldehyde powder on straw bedding, cleaning and disinfection of individual pens after each lambing ewes, collection and disposal of placentas, prompt sucking of colostrum, oral antibiotic within 15 mins after birth as a last resort
What is hypothermia?
Linked to management - primary + secondary hypothermia - 37ºC or less - weak or comatose lambs Brown fat provides internal energy source for about 5hrs
How to manage a hypothermic lamb after the brown fat source is no longer viable?
Primary hypothermia - blood glucose sufficient but environmental losses too high
- mismothering/wet
- warm up (warming box @ 45ºC) and feed once able to swallow
How to manage a hypothermic lamb thats over 6 hours old?
Not enough energy to maintain body temperature, body temperature drops, comatose
If warmed up before n glucose to support increased metabolism - hypglycaemic shock
Can’t stomach tube comatosed lambs
What is the equipment needed for comatose hypothermic lambs?
Kettle Water 50ml syringe 19g 25mm needle Glucose (20 or 40%), oxytetracycline spray
What is joint/navel ill?
Infection of lamb due to ingress of bacteria through the unhealed navel
Signs = menigitis, joint infection, liver abscess, local navel abscess, spinal abscess, etc.
Prevention
- naval dressing, hygiene, colostrum intake
Treatment
- penicillin, dependant of specific clinical syndrome may be unsuccessful
