Last week I responded to a farmer who thought I had given the wrong advice on the economic starter stock for starting a pig production business.
After reading the article, a prospective farmer called Mugo asked me if it was possible to start a herd with only two sows or mother pigs.
Mugo said in his enquiry that he thought two sows would be economical to start a farm as the cost of buying starter stock would be minimised by rearing and breeding the starter stock from two weaner piglets.
So, in Mugo's opinion, each mother would produce 10 breeding pigs from the first litter or set of piglets.
Mugo was optimistic that within a short period of time -- a period he did not define -- his farm would be full of pigs, thanks to the short gestation, suckling and maturation period of these animals.
Mugo's hypothesis may be true to some extent, but the realities of breeding contradict his optimism.
They fail to take into account the business and biological decisions that a farmer has to make when breeding to increase the population of his animals organically.
It is true that pigs reproduce quickly compared to cattle, camels, sheep and goats. But they still reproduce more slowly than rats, rabbits and chickens.
The problem with multiplying cattle is that, under the best management, they only produce one calf a year.
After that, the female calf will give birth to another calf on average 24 months after birth.
Goats and sheep, on the other hand, give birth to one or two lambs a year and each lamb will give birth to another lamb about 12 to 14 months after birth.
Rabbits and rats reproduce and mature quickly. This means that their numbers grow quickly, and their populations increase rapidly.
To return to Mugo's question and hypothesis, he was alluding to the possibility that he could build up a large herd of pigs without incurring the initial high cost of buying breeding stock.
While I would answer Mugo's question in the affirmative, I would also point out that much of the savings that can be made in the purchase of the initial stock will be offset by the cost of maintaining the pigs until they reach an adequate number.
During the period of herd establishment, Mugo would need another source of money to finance the multiplication of his animals.
I will demonstrate the impact of Mugo establishing a large herd using the reproduction of two female piglets.
I assume that Mugo would start with two female piglets at two months of age. It would take the farmer another seven months for the piglets to reach the optimum breeding age of nine months.
At nine months of age, the pigs would be fed to give birth or farrow at 13 months. At this point, Mugo would have 10 piglets that would mature into adults.
Under normal circumstances, we would expect him to have five male and five female piglets. However, only about three piglets would be suitable for breeding.
In any group of piglets born together, a few may not be suitable for breeding due to natural physical defects such as small teats, small number of teats, hernia and lack of thrift.
We can therefore predict that Mugo's first litter would only produce three mature breeding sows instead of the 10 he thought he would have.
If they all kept to the first insemination, they would take about four months to farrow 30 piglets, but only about nine females would be selected for breeding.
In a further 13 months, the nine females would give birth to a further 90 piglets from 45 females, of which only about 40 would be selected for breeding.
After about 13 months, the 40 females would farrow 400 piglets and about 215 would be selected for breeding at nine months of age.
The total time to reach the population of 215 breeding females from one piglet would be about 57 months, or about five years.
As Mugo would have started with two sows, his total number of breeding sows would be 430.
By Kenyan standards, this would be a large herd, capable of producing 4,300 piglets when fully bred.
The number would be higher because I have not taken into account that piglets would also come from older sows.
Although Mugo would have built a large herd from two weaner piglets, there are disadvantages to this direct low-cost route.
This would deprive Mugo of further production and put him back to square one, with no guarantee that the second set of piglets would survive.
Another disadvantage is that Mugo would be spending money to build up the herd while not earning much from the pigs.
I am not aware of any comparative study of the costs of starting a pig farm in this way compared to buying an economical starter stock from the outset.
As the pigs are reared on commercial feed, Mugo would need to have a source of income to fund the establishment of the farm until the pigs reached a large enough number to be economical.
Whichever method of starting a pig herd is chosen, it is important to have sufficient funds to get the business off the ground.
