Hello Dr Messo

Some of my chicken are releasing watery black stool while others white. What could be the problem and best medication? They look sickly. Alex.

Dear Alex, watery black stool in chicken from the age of 2-4 weeks is predominantly seen with flocks fed on diet high in fish meal. The fish diet stimulates excess production of gastric juice which in turn damages the lining of the gizzard leading to improper digestion and production of black ingesta commonly referred to as black vomit.

The fish if used in animal feed formulation should be well balanced, dried and moisture level reduced to less than 12 per cent. The white feacal material is normal urates only released occasionally and is perfectly acceptable. You should consult your feed supplier and change to a new batch or alternatively buy from a reputable miller. If no action is taken, you can easily lose 4-8 per cent of your birds due to this condition. In the second question on medication, my answer would take a more in-depth discussion. 

I have on several occasions been asked questions about poultry health and it always goes like: “Daktari ni dawa gani nitanunua?” ‘which medicine should I administer? Over the years I have encountered commercial farmers keeping more than 200 broiler birds at a go rearing them without the use of any antibiotics with minimal mortality of less than 3 per cent. This week, I visited a layer farm in Embu County growing 20,000 pullets to 14 weeks of age with a cumulative mortality of 1.4 per cent in cages without application of any antibiotics at all. He has been farming for the last two years with good success rate. When I asked him how he manages, he shared with me the following information:

Cleaning and disinfection prior to placing your birds.

A good start is a clean start, you need to thoroughly dry clean your units by removing old manure, dust, feathers by sweeping and dumping them at least one kilometer away from the unit or farm. The old manure is the natural breeding ground for worms, coccidiosis causing organisms, bacteria like E. coli, staphylococcus, while the feathers can harbour Mycoplasma and Mareks causing organisms. Wash the house with plenty of water focusing on the walls, roof, equipment like feeders and waterers. About 95 per cent of the micro-organisms are removed by water alone on high pressure and low volume preferably using car wash pumps. The other 4 per cent are removed by disinfection using local quaternary plus Glutaraldehyde disinfectants like TH4, Virukil, Bimacide, Ultracide.



Source of chicks

Have a conversation with your chick supplier and buy high quality chicks with repeatable good traits like livability, good feed conversion ratio, disease resistance, high daily body weight gains etc.

Feed and water

Good palatable feed that is well balanced and adequately supplied is paramount for a good start. Remember that high protein starter diet well balanced with minerals are required for organ development and immunity. Weigh a sample (5 per cent) of your birds every week and record the growth rates. Make it your duty to constantly visit the farm at least once per day during feeding time to observe feed and water intakes. Remember you can only expect what you inspect. Your water should be chlorinated all the time, physically clean and drinkable.

Optimal environment



The most critical period in poultry farming is brooding stage. Provide a comfortable environment for organ development, growth and immunity establishment during this critical period. Protect these birds from chilling and over temperatures and ensure there is no access to the units by rodents and cats.

Bio-security

This is defined as all measures put in place in the poultry site to ensure your flock is protected from disease causing organisms. Keep the site fenced off, do not allow unnecessary visitors into your flock house. Provide clean uniform and boots to your farm helper and any important visitors.

Finally, routinely vaccinate your birds as advised by your local veterinarian and report any ill health to your vet.

Please contact me for more information @smartharvest

[The writer is the Head Vet at Kenchic]