Suppose a new farmer starts with five hens. One of her neighbors owns a rooster to fertilize the hens’ eggs. After three months, she can have a flock of 40 chicks. Eventually, with a sale price of $5 per chicken—which is typical in West Africa—she can earn more than $1,000 a year, versus the extreme-poverty line of about $700 a year.

Africa has a population of 1.1 billion. If every 3rd African owned 30 chickens then there would be over 10 billion chickens in Africa. At a feed conversion ration of 2:1 you are looking at 20billion LB of feed/biomass. To get to his $1000 target every African would need to 1000/5= 200 chickens per year or more simply at a assumed unit weight of 5lb each a total of 1000lb of chicken a year. Now assume 366million people are doing this at our 2:1 conversion ratio so 366B people1000lb/year2lb feed/per lb chicken and were up to 732Billion LB of feed/biomass.

Lets take a real rough estimate of how much food Africa might consume if everyone only ate rice.

Rice is 130 Calories per 100g. Lets assume a daily value of 2600 calories per person.

2600/130100= 2kg per person per day. Converting back to standard 2kg2.54lb/kg=5Lb a day. At 1.1billion people X365 days thats 2007 Billion LB.

So very roughly speaking you would need 732B/2007B = .36 X100= 36% more food produced in africa to cover this.

Now this isn't quite right because those chickens are likely all being consumed local so your average person would now supplement his or her diet with chicken so each 1lb of chicken feed actually reduces the need for human feed by .5lb. so the net increase is actually (732-7320.5) so back to 366b.

366B/2007B=.18 100=18% more food/biomass.

At first pass 18% additional required to do this feed/biomass is not hugely unreasonable but has some problematic assumptions. 1st its assumed that all chicken food is free. If you factor in the cost of feed at say 50c/lb you need to double the volume to produce the same amount of profit and a 36% more feed/biomass.

If people are living in shanty houses where are they going to keep 40 chickens? Reasonably speaking you need at least 40 sq ft of cages at a commercial farm operation scale and 120 at a backyard scale.

Then there is also the assumption that the price of chicken is fixed. If one were to increase chicken production 6X is it really reasonable to assume prices stay constant at 1$/lb?

What about initial investment in cages and fencing? How much will that cost? How about predators?

How about diseases?That many chickens will spread disease like crazy.

Overall though I would say its a good idea at 5-10 chickens , just not one that will necessarily scale all that well. Encouraging some chicken ownership works well up until you hit the point that your scraps and available local biomass exceeds what the chickens eat daily. Once you have to supplement a large part of the feed the necessary scale becomes too large to work well.