1. Sheep Farming in NZ and its interaction with the Veterinary Profession.
Barny Askin

2. The Early Years
Pre 1960 NZ sheep industry based on wool with some lamb exported.
Wool worth $63/kg in 1959 in todays terms. Today $3.50/Kg !!
Mid 60’s onwards more focus on meat.
Today 85% of average sheep farmers income from meat.
Early breeds were Romney and Merino
Border Leicester and Lincoln were introduced to improve wool production.

3. Meat Breeds
Once meat became focus cross breeding took off and new breeds were created.
Coopworth
Perendale
Average lambing % lifted from 105% Sheperded 135% unshepherded.
>150% unshepherded is now not uncommon.
Kg of lamb weaned per ewe has gone from 30kg on average to 42kg.
New breeds introduced in 80’s inc Texel, Finnish Landrace, White Headed Marsh, Oxford Down and Gotland Pelt.
Survivors are the Texel and Finn. Both as part of a composite.

4. The Coopworth Developed to lift the fertility of the Romney
Introduced Border Leicester Genetics
The 2nd largest ewe flock in New Zealand
Developed at Lincoln University.
Dual purpose Meat and Wool.
Some very high fertility flocks around.

5. Perendale A cross between a Romney and a Cheviot.
Mainly a meat breed today. Used to be valued for their wool
Easy care and well suited to harder hill country.
Numbers decreased now as modern Romney is well suited to lamb production from similar environment.
Developed at Massey.
Generally not as fertile as the Coopworth.

6. 1965

10. The Challenges
A number of challenges exist when trying to achieve profitable sheep production from a 100% pasture based system.
Internal parasitism.
Facial Eczema.
Climate. High losses are the norm.
Maximising pasture utilisation.
As vets involved with all of these at every level.
Helping farmers to reduce the impact of these by careful planning.

11. National Drench Resistance Survey
Sheep:
20% of farms no resistance
80% some level of resistance
13% of these had resistance to all 3 families.
56% of these had resistance to 2 families.
Risk Factors were Identified and include:
Use of long acting products pre lamb.
Post lambing treatment of ewes.
Drenching on to clean pasture.
Buying resistant worms.
Use of single actives

12. Wormwise National worm management strategy.2005.
Farmers wanted a consistent message.
Meat and Wool, MAF sustainable farming.
Series of workshops around the country.
Handbook.
Introduced the concept of “refugia”. New to many farmers.

15. Ingestion of L3 larvae - adapted from Coop et al 1982
This slide demonstrates the importance of larval challenge. It shows that under low challenge growth rates are acceptable but at high challenges growth rates suffer. It also shows that even under severe challenge with very regular drenching growth rates will suffer. Drenching at 21 day intervals suppressed egg counts but only restored 20% of the loss in growth rate.
Oral drench at 21 day intervals
- adapted from Coop et al 1982

16. The cost of larval challenge
Lambs drenched every 21 days with high challenge grow only 68% as fast as lambs on low challenge and not drenched.
These drenched lambs on high challenge will take 44 days longer to get to slaughter
They will consume the same amount of feed needed to put one condition score on a ewe
A ewe lifted from BCS 2 to BCS 3 by mating will earn $13 more

17. Veterinary Input Advice on product. Monitoring need for drenches.
Whole farm testing (FEC reduction test).
Planning and putting strategies/systems in place to reduce the impact of worms on production.
Education on good practice.
Stewardship of product.

20. Facial Eczema Fungus Pithomyces chatarum found on pasture.
Fungus produces spores when conditions are right.
Spores contain a toxin. Sporodesmin.
Sporodesmin causes liver damage.
Photosensitivity.
Monitoring
Prevention better than cure.
FE tolerant rams

21. Traditional Role of Vets for Sheep Farmers
Internal Parasitism.
External Parasitism.
Trace element Deficiency.
Brucellosis testing and Ram Soundness.
Lameness.
Infectious reproductive losses.
Post mortems.
Vaccination policies and general disease advice.
Ill thrift investigations.
Animal health plans

22. Advisory role for vets
Not just veterinarians but as a profession very well based to do this.
Interact with all aspects of sheep production.
Profitability driven by many factors, eg:
Ovulation rate
Lamb survival
Lamb growth rates
Many vets well versed in these areas.
Specialist advisory role..eg T. Cook .Consultant.
Ambulatory vet becoming involved with advisory work as well as day to day. Probably more common.

23. Drivers of profit in sheep systems
Pregnancy scanning
Lamb survival
Lamb growth rates to weaning
Lamb growth rate after weaning
Consuming as little feed possible to maximise the above

24. Beef and Lamb farm survey data
Fourth Quintile
Top Quintile
GFR/ha
$1067
$1266
EFS/ha
$258
$434
Sheep gross margin
$90/SU
$108/SU
Lambing %
143%
145%
% lambs hoggets 1%
11.5%
Fertilizer
$12.31/SU
$12.26/SU
Animal health
$4.92/SU
$4.35/SU

25. $812 $770 171% 63 kg ewes, 10/ha, lambs sold @ weaning Status quo
15% ewes ≤BCS 2.5
Increased CR
5% ewes ≤ 2.5
Scanning %
160%
171%
Lamb survival
78.2%
Weaning weight
26.5 kg
Gross Margin $/ha
$770
$812

26. Increased lamb survival
63 kg ewes, 10/ha, lambs weaning
Status quo
15% ewes ≤BCS 2.5
Increased CR
5% ewes ≤BCS 2.5
Increased lamb survival
Scanning %
160%
171%
Lamb survival
78.2%
80%
Weaning weight
26.5 kg
Gross Margin
$770
$812
$848

27. Increased lamb survival
63 kg ewes, 10/ha, lambs weaning
Status quo 15% ewes ≤ BCS 2.5
Increased CR
5% ≤BCS 2.5
Increased lamb survival
5% ewes ≤BCS 2.5
Increased weaning wgt
Scanning %
160%
171%
Lamb survival
78.2%
80%
Weaning weight
26.5 kg
27.5 kg
Gross Margin/ha
$770
$812
$848
$898

29. To make profit from pasture
Grow lots of pasture
Utilise over 80% of pasture grown
Allocate the minimum amount of pasture to achieve the production objectives

30. Controlled grazing systems
Being in control of the allocation of pasture
Precise control of supply/demand
Can adjust supply to meet variable demand
Enables supply planning
Encourages pasture to grow more
Lifts pasture quality
Is the way to maximise pasture utilisation

31. Controlled grazing systems – the how
Knowing the feed demand – this can be very precise.
Assessing the feed available – is never a precise measure.
Anticipating the supply of feed ahead – requires a lot of assumption.

33. The reality of profit from pasture
In pasture grazing systems profit is the outcome of production/hectare
Production/ha is the outcome of stocking rate and per head performance

34. The challenge Stocking rate verses a drop in per head performance
Top operators achieve both
The bits to preserve:
- condition score at lambing
- pre lambing/calving feeding
- condition score at mating
Tools to help
- weaning date
- nitrogen
- knowing the flexible plan

35. Rotational grazing
The planned allocation of pasture that delivers the required amount of feed and allows the recovery of pasture cover

39. Setting up a grazing system
The variables are:
- grazable area
- expected pasture growth rate
- pasture cover at start
- needed pasture cover at end
- the animal demand – weight, reproductive
status

40. The rules Rotation length is set by the required end pasture cover
In the winter, grazing per break should be a maximum of 4 days
Use residual dry matter (RDM) as guide to adequacy of feeding
˃1200kgDM/ha – full intake
˂950kgDM/ha – below maintenance
Monitor
Body Condition
Growth Rates
Pasture Covers

41. The End