Fowl Typhoid and Pullorum: The Silent Salmonella Killers

A layer farmer in the Ashanti Region once described his problem to us as "dying slowly, three a day." His 1,200 hens were 35 weeks old and in good production. Every morning he found two, three, sometimes five dead birds, always the plump ones, with no coughing and no nervous signs. When a veterinary officer finally opened one, the liver was swollen and bronze-green and the spleen was twice its normal size. It was fowl typhoid, probably on his farm since the chicks arrived.

Fowl typhoid and its close relative pullorum disease are caused by two types of Salmonella that live only in birds. In Ghana they remain common, partly because the bacteria pass from hen to chick through the egg, partly because they survive for months in dust and droppings, and partly because they mimic so many other problems. This guide covers both together, because they share a cause, a route of spread and a prevention strategy.

Two diseases from one family

Pullorum disease is caused by Salmonella Pullorum and mainly kills chicks in the first two to three weeks. Fowl typhoid is caused by Salmonella Gallinarum and mainly affects growers and adult birds. Both pass through the egg from hen to chick, and both spread between birds through droppings, contaminated feed and water, and on boots and hands. Neither infects humans the way food-poisoning Salmonella does, but both destroy a poultry business if unchecked.

Pullorum: white diarrhoea and dying chicks

Chicks infected in the egg often die in the shell or within the first two days, which the farmer sees as "weak chicks" from the supplier. Those that survive spread the bacteria through the brooder. By day 5 to 10, chicks huddle near the heat source, chirp constantly, refuse feed and pass white, chalky diarrhoea that pastes around the vent. Some gasp because the infection settles in the lungs. Deaths peak in the second week and can pass 50 percent in bad batches. Survivors grow slowly, and some become lifelong carriers that look normal, lay eggs, and pass the bacteria to the next generation.

The white pasted vent is the sign most farmers remember, but not every batch shows it. Heavy deaths in chicks from a new source, when brooding is correct, should always raise the question of pullorum. Our guide on why chicks die in Ghana covers the other causes.

Fowl typhoid: the adult bird killer

In growers and layers, fowl typhoid can be acute or chronic. Acute cases show dull birds with ruffled feathers, pale combs, yellowish-green diarrhoea, thirst and an egg drop, dying within days. Chronic cases are the "three a day" pattern: steady deaths over weeks, often of good-looking birds in full lay, adding up to 10, 20 or 30 percent by the end. On post-mortem, the liver is enlarged with a distinctive bronze or greenish tint, the spleen is swollen, and the ovary may have discoloured, misshapen follicles. Anaemia is common, which is why combs look pale.

Brown-egg strains seem more susceptible than white strains. Heat, moving, overcrowding or another disease often tips a carrier flock into an outbreak; around Kasoa we see fowl typhoid flare in the hottest months and again after the stress of coming into lay.

How Salmonella gets onto your farm

The most important route is the egg: an infected hen passes the bacteria into a proportion of her eggs, and the chicks hatch already carrying it. The disease therefore often arrives with the day-old chicks, from a hatchery using eggs from untested breeder flocks. The second route is carrier birds: a recovered hen, mature birds bought from a neighbour, or the local chickens that wander through many compounds. Then come contaminated feed, especially fish meal or feed spoiled by rodents; crates and vehicles shared between farms; and people, via their boots. The organism lives for months in dry litter, so a house that was "swept" rather than properly disinfected after typhoid will infect the next flock.

Signs, damage and control at a glance

Costs are orientation ranges based on common products at agro-vet shops in southern Ghana. Confirm prices, products and dosages with a veterinary officer before treating.

Treatment: what it can and cannot do

Antibiotics such as enrofloxacin, sulphonamide combinations or amoxicillin, given in drinking water for five to seven days, usually cut deaths sharply within two or three days. The bad news is that they do not remove the bacteria from carrier birds. When treatment stops, the disease often returns two to four weeks later, and each round costs money, lowers production and encourages resistance. Read our article on antibiotics in poultry before starting any course.

For a small backyard flock with confirmed typhoid, the honest advice is to sell the birds for meat after the withdrawal period, clean out and restart with clean chicks. For a larger layer flock, treat to control deaths, remove sick birds, improve hygiene, and plan to replace the flock. Never hatch eggs from a flock that has had typhoid or pullorum.

Prevention that starts at the hatchery

The only way to break the egg route is to buy chicks from hatcheries whose breeder flocks are monitored for Salmonella and whose hygiene is sound. This is one of the strongest reasons to buy from a known source, as we explain in our guide to choosing healthy day-old chicks. On the farm: all-in, all-out so no carrier flock overlaps with new chicks; proper disinfection between batches; keeping local chickens away from commercial houses; footbaths and dedicated boots; rodent control around feed; and fish meal from suppliers you trust.

Where fowl typhoid is common, a live 9R vaccine is available through veterinary channels for layer pullets at around 6 to 8 weeks, often repeated at 14 to 16 weeks. It does not protect against pullorum or stop all infection, but it substantially reduces losses. Discuss it as part of the flock vaccination schedule. The general farm defences are in our biosecurity guide.

Frequently asked questions