Lambing all over the world
In this blog, we’ll be taking a little trot around the globe to some of the countries with the highest sheep populations in the world including China, Australia and New Zealand to compare their systems and routines and discover any learnings for the benefit of our own sheep farming community.
How it’s done at home
With more than 15 million ewes preparing to lamb down, spring is the most common time for lambing here in the UK and Ireland. Our lambing season is of course primarily determined by the natural breeding cycle of the ewe. With the majority of breeds typically coming into season in the autumn, naturally lambs are going to appear approximately 4 1/2 months later. The only exception being the Polled Dorset which are fertile year-round. With this in mind and taking local climate and geography into account, lambing can occur any time from December onwards and continue as late as June.
The benefit of this system of course is taking full advantage of natures’ seasons. Winter allows us to more easily maintain the condition of our breeding ewes so that they stay in prime condition for lambing – either slimming down those that are ‘fuller figured’ or giving the leaner members of the flock a helping hand with additional nutrition. Spring is the season of new life all round and provides our newly lambed ewes with the benefits of fresh spring grass – providing their lambs with the best possible start.
Summer provides our lambs with good conditions for growth – a consistent diet and favourable weather and, post-weaning, allows the ewes to regain some condition before autumn tupping starts again.
How they do it down under
In Australia, it is considered that ewe condition leading up to lambing is more important than her condition at joining (tupping) due to the impact of poor nutrition on the ewe and unborn lamb. Supplementary feeding here is expensive and inefficient, so it is considered best to match finest pasture and paddock feed to late pregnancy. Balancing this with the ewes’ natural breeding season, which obviously has an impact on reproductive rates, is vital to maintain ultimate profitability.
A ewe’s energy requirements double in late pregnancy and triple in lactation and her condition will vary across the season, depending on available feed. With this in mind, careful calculation needs to be made with regards to the impact of ewe nutrition on her reproduction, versus the cost.
As in the UK, sheep fertility increases as daylight decreases. In most breeds, ewe fertility is at it’s peak in April, though pregnancy rates from joining in January and February can be up to 20% better than the results of a joining in October and November. Out of season cycling can also be promoted with the use of a teaser ram.
The emphasis in Australia is very much on the available nutrition and the need to provide supplementary feed if required at key stages of the ewes’ reproductive cycle. These include:
- Pre-joining due to the impact of nutrition on ovulation rate.
- Mid-late pregnancy due to the impact on lamb survival rate and future performance.
- Early lactation due to the impact on milk production
- Around the time of minimum fibre diameter due to impacts on wool staple strength.
Where ewes’ condition peaks in early December, they are in better condition for joining in November and December. Such enterprises will have higher conception and fertility rates than those with ewes mated in the natural breeding season when the feed availability is often declining rapidly.
In wool biased enterprise it is considered best to aim for a lambing approximately three to four months before the end of the growing season. This enables ewes to make use of new growth in late pregnancy and weaners to develop to a good size and weight before feed quality declines over the summer.
Australian lamb meat farmers will be required to make a call on the most profitable compromise between ewe : land ratio, nutrition, lamb sale weight and market price.
How have the Kiwi’s cracked it?
In New Zealand, lambing season varies hugely depending on geographical location and climate but generally occurs between August and October. On the North Island, lambing would be well advanced much earlier than the South Island, where snow would still be present later on. Though there are exceptions, with lambings as early as April – some four months out of season, recorded.
Here, lambing outdoors is a common occurrence – and on a massive scale, with minimal supplementary feeding above grass / herbage commonplace. To put things into perspective, there are some 28 million sheep in New Zealand and only 4.7 million people.
As in the UK and Ireland there are farms that embrace triplets and farms that don’t, but where they do, they do it in their thousands with a survival rate of approximately 2.3 lambs per ewe and an approximately 23% mortality rate.
Challenges faced by New Zealand’s farmers include ewes getting cast, prolapse and the weather. There are several theories behind the common occurrence of prolapse but no solid conclusions as to the cause.
Major difference between the UK & Irish sheep farms and sheep farming in New Zealand is the very much hands-off approach.
- Lack of supplementary feeding
- Lack of intervention around lambing
Despite these differences, twin lamb birth weights are a comfortable 5-6kg on grass only or herb / clover swards and ewes have a strong mothering instinct and ability.
And how about mainland China?
On a visit to Inner Mongolia, where the human population is 24 million, livestock forms 50% of the region’s total production. 80 million hectares of grassland accounts for 74% of total land area.
Inner Mongolia is the number one region in China for meat, wool and milk production and 50% of farmers have 500 sheep or more - which is unusual for China, where small flocks are commonplace. The traditional lambing season is from March to May, but in some places lambing is an intensive year-round operation.
The state oversees stocking levels, placing restrictions on numbers to prevent the overgrazing of the region’s ecologically important grasslands. This is limited to one ewe per 2 hectares, which sounds low, but taking sustainability into account in a dryer climate than our own, with longer, colder winters, it is just right.
Sheep breeds here are mainly indigenous breeds with the introduction of Dorset, Dorper and Suffolk used as crossing sires to increase lamb weight and quality. Merino genetics have also been introduced where wool production is a priority.
Inner Mongolia is home to 259 breeding companies developing sheep breeding and 400 companies processing lamb as well as smaller local abattoirs servicing the local communities.
Breeding and embryo transfer sites work with donor ewes and imported rams to multiply the desirable imported genetics. Embryos are then transferred into recipients each month, utilising hormone injections to allow lambing year-round. Each ewe produces around 30 embryos in a continuous programme of synchronisation, during her 2-3 year working life. These breeding farms then cascade the desirable imported genetics out to farms to cross with the native breeds. The resulting lambs then go into feedlots for finishing.
Finishing feedlot farms take in vast quantities of lambs per year (e.g. 30,000), with lambs arriving at 3 months of age and staying, to be fed nuts containing a mix of lucerne, maize and soya as well as imported ad lib hay for finishing. These feedlots are open in the summer and housed in the winter due to the cold weather.
In some instances, the farming, processing and marketing of the lamb meat occurs on the one site in the form of a huge ‘plant’. Either way, the level of investment in product development and interpretation is impressive, with heavy investment in genetics imported from Australia.
The processing industry supplies cuts, rather than whole carcasses to markets, with the whole animal being used in 120 different products. Even with farming on such a scale, China’s consumption of lamb outweighs it’s production, with meat being imported mainly from New Zealand and Australia to meet demand.
So what can we learn?
It’s easy to recognise the differing sheep farming practices around the globe, with various factors influencing each. Climate and nutrition clearly play a huge part in Australia and New Zealand, much like the UK and Ireland, whereas the huge demand on lamb meat seems most influential in China.
Can we learn from the laid back hands-off approach of our New Zealand counterparts or should we take the lead from China when it comes to farming on an intensive and more efficient scale to meet UK and Irish demand for lamb meat? It certainly provides some food for thought.