Farmers using the MTF calculation method (saleable meat per ton of food) have noticed considerable improvements in MTF (5-12%) and lean meat food conversion (8.6:1 down to 4:1, a 53% improvement). The improvement comes from using the radically new method of producing lean meat from a farrow-to-finish farm. Preliminary figures suggest that when using conventional feeds, cost savings of more than 26% are obtained. If using by-product feeds, these savings can be as much as 39% (Table 4 on page 72).
The once-bred gilt system abandons traditional breeding strategy where sows are used over a 6-8 litter lifetime to produce a succession of progeny. With the once-bred system, the gilt is just another slaughter animal, which produces a litter on the way towards her own slaughter at about 285 lb.
The pregnant gilt, while forming her litter, will continue to grow lean meat efficiently. There are no reproductive re-breeding delays and no maintenance food costs.
For example, a 280-lb. sow needs 5.5 lb./day of feed for maintenance alone. The need for an extended acclimation period is removed and housing and veterinary costs are lower. Labor needs are reduced and the skills needed made much easier.
Also, the number of expensive gilts now being culled after their first and second litters is an enormous waste of feed and costs (Table 1). This never happens with the once-bred system.
Thus, the economics of the system are much cheaper. On some farms, it's as high as 35%. But 20% savings in costs are almost guaranteed. The savings comes from the massive cost reduction advantage.
The system is not, in fact, new. Developed 25 years ago, the concept has been much debated - but not adopted - until the current, severe, pig price crisis hit Europe. We now examine anything that can reduce costs.
Why hasn't the once-bred system caught on?
* The heavier cull carcass used to be a problem. It is not now as most European processors can take pigs of 285 lb. The U.S. has always been able to do so.
* Pigs are much leaner, so the gilt carcass doesn't have the fat it did 10-15 years ago (Table 2).
* Better nutritional expertise during lactation means the lean growth the gilt acquires in pregnancy can be largely maintained by weaning time at 28 days.
* There have been advances in controlling the timing of estrus so gilts can be bred at an earlier age.
* Previous complaints from the meat trade of poor gilt carcasses can now be overcome with better feeds in pregnancy.
* More group-housed systems are in place. Pregnant gilts can be housed together without trouble, so housing costs are lower.
How It Works Gilts are selected at 195-220 lb. Stimulation and service techniques are as previously used. But gilts are batched into estrus groups using PG 600, and housed in yards. Any returns and those not pregnant are sold to slaughter. Gilts are fed ad lib in gestation to a week before farrowing. Normal lactation feeding follows.
Gilts should gain approximately 175 lb. of lean tissue from selection to culling with a liveweight feed conversion of about 4:1. A nutritionist's help should be sought to provide a diet to meet those pregnancy and lactation needs.
At present, F2 gilts selected from the producer's own herd do a good job and are at least 60% cheaper than purchased F1 replacements.
The once-bred gilt system produces a totally new generation of breeding gilts from the producer's own herd each year. This rapid generation replacement allows a quick genetic turnover, which is viable. This has been done with care and dedication as follows:
1. Selection of replacement gilts is done on weight-for-age records and absence of fat using ultrasonics. This way, a good handle is obtained on lean tissue growth rate (and essentially lean tissue feed conversion ratio) in the female line.
2. The breeder should also consider litter size of the sow from where the candidate came. While this is not a highly heritable trait, it should still be borne in mind. Independent advice from a geneticist can assist in any selection process.
3. Purchased boars or AI are also chosen from proof of the same, fast, lean growth traits. Thus, performance-testing of the animal and its siblings or occasional progeny testing of the boar or semen's parentage should be requested. Growth rate and ultrasonic evidence are paramount.
4. Good records and, to a certain extent, each farm becoming its own test station should ensure that carcass quality and growth rates do not deteriorate and are more likely to improve over time.
Possible Disadvantages * Will the meat from 280-lb. gilts culled at weaning be of good quality?
Eight years ago, trials suggested there was no problem, but the meat trade is bound to be nervous of this possibility.
* Will the public accept the idea of having no breeding females over 13 months of age?
This is not known. It could be an emotive subject: "They're killing young mothers now!"
* Will the producer sufficiently maintain his genetic improvement from F1 females?
With good records it is possible, but it needs dedication and care.
Will the producer lose too much of the lean gained during gestation - during lactation?
With care and experience this should not be a problem.
The system will not be popular with the breeding companies.
A Suggestion The once-bred concept could be used to complement the conventional system we use now. Only those gilts with lower outputs of number and quality of pigs born and weaned would be culled and sold as meat. This approach is best used in genotypes/herds where the repeatability of litter size is high.
We have experience (limited, but probably sufficient) of the once-bred concept in Europe for me to present in Tables 3 and 4.
The economic points Tables 3 and 4 suggest, under European costings, are as follows:
* The increased MTF approaches 5% or 26 lb. for each ton fed. On what we do now, this is equivalent to 374 lb. more meat produced in one sow's lifetime of 2.4 years.
* The improved margin is raised 18%.
* But a very significant fa ctor is the very considerably reduced costs of achieving this better performance.
* Using group housing in pregnancy and feeding partly by-product feeds costs are reduced by nearly 40%.
* Even if by-product feeds are not available, costs are reduced by between 20% and 28%, so experience suggests.
* Reduced costs of this magnitude have a highly significant effect on cash flow. In the severe, low pig-price situation we face in Europe, it is lack of cash flow which quickly forces people into insolvency.
After four months of phenomenally low returns, the two biggest commercial breeders in Britain have already ceased trading, because they are unable either to maintain or confidently support a future cash flow.
This is why we are looking again at the once-bred gilt concept.
I think you should, too.