Lamb performance

Question 1

• First few weeks critical of lamb

Answer 1

Most lamb losses would occur around 0-48hrs after been born = 49%
Mortality very high in bigger litter sizes
1 in 8/10 lamb would die in early life.
Causes of mortality = exposure & starvation (30%)
Disease problems (20%)
Accidents & starvation (5%)
Birth defects (5%)

Question 2

• Lamb relies on dam = no immune system

Answer 2

are hypo-immunocompetent
Colostrum needed in first 24hrs
Help prevent hypothermic.
Helps build immune system.
Provides antibodies = IgG
Most receive 50ml/kg lamb weight & 1L first day
Newborn = limited energy reserves = especially small lambs
Would lose heat quickly
Wet lamb loses heat 8 times faster than dry lambs.
Difficult births = lead to low blood oxygen levels, low ability to produce heat & become colder quicker
BAT stored in neonatal lambs for few hours = which generate own heat
Only till gets colostrum.

Question 3

• Newborn lambs = no resistance to diseases

Answer 3

Colostrum helps with these = helps with passive transfer of immunoglobulins & gut closer.
First few hours = gut more open – allow immunoglobulin through they are big components
After 24hrs gut gradual close to stop bacteria entering – once get colostrum.

Question 4

• Feed quality & quantity is important for late pregnancy =

Answer 4

for enough colostrum,
& minerals needed
Excess iodine in last 2 wks of pregnancy = bad = affects lamb serum IgG levels
Results in pre-programmed lambs born = won’t be able to absorb the antibodies.
Iodine = impact T3 – biologically active form.
Impacts gene expression. – change thyroid hormone at intestinal level = reduce interaction with thyroid hormones in circulate.
Correct requirements of energy & protein = have strong & healthy lambs

Question 5

• Other problems impact growth & performance include:
  E.coli injection =

Answer 5

when pH of stomach is too high
- use oral antibodies or 20-40ml of natural yoghurt
- yoghurt – reduce the pH & adds lactobacilli bacteria to stomach

Question 6

Deficiency of cobalt =

Answer 6

lead to lazy/weak newborn lambs & slow to get up & go = need to fix before mating

Question 7

Joint ill =

Answer 7

poor hygiene conditions during lambing, insufficient colostrum, wasn’t treated in first 12-24hrs
Swelling around the joints due to fluid
Use anti-inflammatories
Lack of selenium in diet = lead to lazy/ weak lambs slow to suckle = prone to diseases

Question 8

• Pasture quality needs to be good

Answer 8

Mixed grazing = increase GR by 10-15%
Better utilisation of grass – dilution of parasite burden.
MSS = high production levels & good feeding value
Trials done: MSS with 6 species
- Improved GR improves = 18% higher, 2.4kg heavier WW & reduce slaughter day by 2 weeks
- 10 weeks of age = lower parasite burden – less time on the farm
- Less anthelmintic use – less need for drenching or prolonged the intervals.
- Using MSS meant less methane production of lambs
* Timing of lambing important
Should link with grass growth = so perform better with enough grass growth
Management made easier

Question 9

• Weaning

Answer 9

Weaning should be at 14 weeks old
Weighting single = 35kg.
Twin 29.5kg
Could wean at 6 weeks but not recommended = impact growth rate.

Question 10

• Factors affect lamb growth on grass:

Answer 10

• Prolificacy potential – no lambs born/ewe/year
• Stocking rate.
  Impact how much grass they will receive = medium Stocking Rate means = more potential to them to grow & meet targets
  IF high SR = could lead to impact on GR = getting less grass.