By Dr Andrew Tucker, Charles Street Veterinary Consultants
Three week batch farrowing systems have become fairly common particularly on “smaller” units. Not much use is however made of other batch farrowing systems, particularly on larger units. The following article was presented at the recent Charles Street Veterinary Consultancy Farmer’s Day.
The purpose is simply to have a closer look at the workings of the various batch farrowing systems and try to weigh up the pro’s and con’s. Would one of these systems make your unit more efficient?
Batch farrowing systems tend to be quite confusing from the outsiders point of view and this is often the reason why they are not considered as an option. In actual fact the running of these systems is not complicated and all and often a lot more straight forward then the one week batch farrowing system that most farmers currently use.
One week system
This is the method currently used on most farms and is often incorrectly accepted as the only way that pig flow works. This consists of 21 sow herds that are one week apart in their production cycle (or 20 herds if you wean at 21 days). When group 21 finishers group one will follow the next week. This means that you must serve a group of sows every week and hence you also farrow and wean sows every week. So you perform the three “vital functions” on the piggery every week, namely serving, farrowing and weaning.
Three week system
With this system you only have seven herds on the farm instead of 21. These herds are all three weeks apart in their production cycle and they are three times bigger then the individual groups. So when group 7 completes their cycle, group 1 will follow three weeks later. The way this works out is that you only perform one vital function per week i.e. week 1 = farrow, week 2 = wean, week 3 = serve. Each of these vital functions is now, however, with a group that is three times larger.
I find that this improved structure on the farm helps the management and focus on the farm tremendously. Only one vital function is performed per week so the manager can be present the whole time and not distracted by other functions. The greatest advantage to a three week system is undoubtedly the fact that the groups are three times larger. This allows a smaller unit to effectively apply all-in all-out farrowing, weaner and grower houses.
All-in all-out can for example now be done on a house basis instead of just a room basis because of the bigger group size. One prerequisite of the three week system is that the farm uses A.I. and not natural services. To manage a three week system with natural services means that you would need three times the number of boars and this is not cost effective. The disadvantage to the system is that you need 20% more farrowing space to allow the same number of sows through the system.
Two week system
With this system you have ten herds two weeks apart. Batches are therefore twice the size. The system works most efficiently as a 21 day weaning system and then uses less farrowing space (20%) then a standard system. The greatest potential for this system lies with established large units that have all-in all-out grower buildings. This would allow them to fill these same buildings with a single sex and thereby allow accurate single sex feeding plans.
Four week system
With this system you have five herds four weeks apart. Batches are therefore four times bigger. This again makes more efficient use of the farrowing space if planned with 21 day weaning. The farm’s three vital functions are only performed once every 28 days. The way that this works out is that you serve and farrow in one week, have two weeks “off” and then wean in the fourth week. These two weeks “off” will allow much needed time for maintenance work, staff training and jobs of the sort that are often placed on the backburner.
Five week system
This is the upper limit for most commercial piggeries. Four Herds, five weeks apart. No additional farrowing house space is needed. There are 21 and 28 day weaning options both with pro’s and con’s. Here you only perform the three vital functions every 35 days. The con’s to this system which would have to be dealt with are that you would get gaps in your marketing. Depending on your market you would probably market three weeks running and then skip two weeks.
You would also have to rely on products to synchronise your sows. In the shorter systems batch weaning is used to synchronize any sows that have moved out of their week. In this system you would not be able to cope with any sows out of their week as the piglets would in some cases potentially be too young to wean.
Six to 21 week systems
These become impractical in a South African context because of the type of farrowing houses we use. The use a farrowing space becomes wasteful with much downtime.
In outdoor farrowing systems these systems are used particularly where piglets are sold to contract growers. Take a 100 sow unit for example who is selling 47 weaners per week. Using a 21 week system he can now sell 987 piglets in a batch. He can now sell to a completely different cliental and only performs his three vital functions every 147 days.
Whichever system you are using on your farm, the final goal is certainly optimal production. Every farm is unique and it is worth investigating whether a different batch farrowing system would suit your farm better or not.