Estimated reading time: 7 minutes
- “The building blocks of our flock are fertility, genetics, and maternal traits,” says Lodie van Reenen of the Nova Barletta Dormer Stud near Clocolan in the Eastern Free State.
- Visual assessment remains the foundation of our selection, but we also rely on numbers.
- Because there are only a limited number of lambing pens, only ewes confirmed pregnant with twins are housed inside.
- According to Chriselle, synchronisation is an important tool for making their system work efficiently, especially given their limited resources.
- Synchronisation and lambing pens, Lodie says, work hand-in-hand; one cannot be fully effective without the other.
“The building blocks of our flock are fertility, genetics, and maternal traits,” says Lodie van Reenen of the Nova Barletta Dormer Stud near Clocolan in the Eastern Free State. The stud takes its name from the farm on which it is based and is part of Zuikerkop Boerdery, which also houses a Hereford stud, a commercial cattle herd, Merino stud, grain division, and a mill in town.
Lodie and Chriselle van Reenen focus exclusively on the Dormers, while managers oversee the other divisions.
The value of balance
“The aim,” explains Lodie, “is to breed rams and ewes that can pass their superior genetics on to the next generation. If we achieve that, we’ve succeeded. Visual assessment remains the foundation of our selection, but we also rely on numbers. For instance, we won’t use an animal for breeding if its Logix Merit Index (LMI) is below 90.
“At the same time, we avoid extremes. We strive for a balance between conformation and performance figures that exceed the breed standard.” In addition to fertility and conformation, the Van Reenens select specifically for growth and feed conversion efficiency.
They note that every breeding goal must be tailored to the farming operation’s circumstances. “We have around 600 stud ewes and 1 400 commercial ewes that we breed each year. Our lambing pen facilities can accommodate only 300 ewes at a time, which is why we spread lambing over six months: one week each in March, April, May, June, July, and August. In exceptional cases, we may lamb a group in September, but we are committed to ensuring that lambs grow strong before having to face the summer heat and associated disease and pest challenges.”
The lambing system
Because there are only a limited number of lambing pens, only ewes confirmed pregnant with twins are housed inside. The rest lamb in small outdoor pens near the homestead.
“We only have one lambing week per month,” Lodie explains. “This is achieved by synchronising the ewes and performing insemination via laparoscopy, without introducing follow-up rams afterwards. This ensures that the ewes lamb within a very short timeframe, allowing us to clear and thoroughly clean the pens for the next group.”
Group one ewes that skip are moved to group three, and so on. However, each ewe is allowed to skip only once; if it happens again, she is culled. Ewes in the final group that skip are culled regardless.
Laparoscopy allows us to get our entire stud pregnant using just five or six of the very best rams, which greatly accelerates genetic progress.
Role of synchronisation
According to Chriselle, synchronisation is an important tool for making their system work efficiently, especially given their limited resources. “We consider the lambing pens to be an essential resource. They protect our animals from predators and significantly reduce lamb mortality. We have many multiples, and the pens allow us to monitor them closely during those critical first few days.”
Only the stud ewes are inseminated laparoscopically. The commercial ewes are also synchronised, but they are naturally bred to rams introduced for a five-day period. “Laparoscopy allows us to get our entire stud pregnant using just five or six of the very best rams, which greatly accelerates genetic progress.”
The Van Reenens began synchronising their animals in 2013. Initially, they used artificial insemination, but since 2018, have relied on laparoscopy. “With laparoscopy, our conception rate is between 82 and 85% without a follow-up ram, compared to just over 50% with conventional artificial insemination. Moreover, our multiples currently account for 71%, depending on environmental conditions during the breeding season.”
Selection and genetic progress
For them, explains Chriselle, the primary advantage of synchronisation is that it allows for optimal use of resources, while radically accelerating genetic progress. “Because we use so few rams in a season, it is essential to keep inbreeding levels in the flock under control. However, with careful selection, this is entirely achievable.”
Nova Barletta has already earned multiple platinum awards at the annual SA Stud Book Elite Awards, recognition that reflects the significant genetic progress being made. Each year, the top five small-stock stud farms in the country, across all sheep breeds, are honoured with a platinum award.
Synchronisation and lambing pens, Lodie says, work hand-in-hand; one cannot be fully effective without the other. “Synchronisation allows for precise lambing planning tailored to the most optimal times for our particular environment. During the lambing week, we can concentrate all our human resources on accurately managing the process.
“This meticulous management, combined with a high percentage of multiples, pushes our weaning percentage close to 165%. It makes the additional investment in synchronisation and laparoscopy well worth it. Furthermore, the mortality rate from birth to weaning remains below 3%.”
Flush feed
Conception rates, whether through natural breeding or artificial insemination, are at their peak when the ewe’s body condition is improving (in other words, when her weight is increasing). According to Lodie, this is a key management factor in successful sheep farming. “These days a lambing percentage of 80 or 90% is simply not acceptable. Margins are too tight and your profit comes from the number of lambs on the ground.”
In their operation, he explains, nutrition is increased around a week before the sponges or CIDRs are inserted. At the same time, the ewes are treated for internal parasites and supplemented with vitamins A, D, and E. They continue with the flush feed until roughly three weeks after laparoscopy, after which the ewes’ diet can return to normal levels.
Creep feed for lambs is equally important, he adds. “We start giving creep feed when the lambs are a week old. Initially, they consume very little of it, but intake gradually increases as they grow and get used to the ration. By weaning time, the transition to a feedlot ration for slaughter lambs is seamless. Lambs retained for breeding or included in feed conversion trials are also accustomed to concentrates by this stage.”
The benefits of synchronisation
If Lodie were to summarise the benefits of synchronisation, the primary one would be that it significantly shortens the lambing period, simplifying overall management. Because the lambs are roughly the same age, weaning and marketing become much easier, and performance measurement is more accurate since peer groups are nearly identical in age.
Where the ewes are concerned, synchronisation allows larger numbers of animals to be managed within the same infrastructure, as groups can be divided accurately and predictably. Nutritional management is also simpler because the stage of each ewe’s production cycle is known. This also simplifies pregnancy testing.
Additionally, it becomes easier to quickly identify and cull ewes that consistently struggle with lambing or fail to produce enough milk. “Another advantage for young ewes,” adds Chriselle, “is that we place all our young ewes in one group, so they receive the special attention they need.”
The best mothers
Critics often point to flaws in systems like the one the Van Reenens operate, particularly that ewes with poor maternal abilities are allowed to remain in the flock. However, their own experience tells a different story.
“Mothering abilities involve several aspects. The first is milk production – we immediately notice if a ewe is not producing enough. The second is her nurturing instinct; any ewe unwilling to let her lambs suckle is culled. Because our ewes along with their lambs move from the lambing pens to small paddocks, we are able to notice quickly when a ewe fails to keep her lambs close. These ewes are also removed.
“Since we started synchronising all our ewes in 2013, our observation is that their maternal abilities are improving, not declining.” – Izak Hofmeyr, Stockfarm
For more information, contact Lodie and Chriselle at 072 597 6047.
