THE REALITIES ABOUT POULTRY The Modern Farm - The Realities About Poultry_Seco | Page 110

Minerals: A wide range of minerals are required by poultry. They are available in good quality
commercial feeds. Calcium and phosphorus, in particular, must be supplied in balanced
proportions. Young birds require a ratio of calcium to phosphorus of 1:1; however, laying birds
require a ratio of 5:1. Commercial layer diets have calcium incorporated in the mix; otherwise,
extra calcium can be supplied by using shell grit or limestone.
If young chickens are given layer feed, the high calcium content can reduce the growth rate and
delay sexual maturity. A deficiency of calcium in the diet can also cause a reduction in the
growth rate, as well as rickets in young chickens. In layers, it can cause fragile bones or thin-
shelled eggs. A phosphorus deficiency can also cause rickets in chickens.
Toxicities (Poisoning)
Aflatoxins: Aflatoxins are poisons produced by certain strains of the fungus Aspergillusflavus.
Tropical conditions are ideal for the growth of fungi and contamination of feed is fairly
common. These poisons affect the liver and the immune response to some diseases, such as
thrush and coccidiosis, may be reduced.
Ducks, geese and turkeys are very susceptible. It is a very difficult condition to diagnose as there
are no specific clinical symptoms to show the presence of the poisons.
By providing fresh food daily and removing any uneaten food, the chance of this fungus
growing is reduced.
Salt:Salt poisoning, caused by common salt, is usually found in birds fed food scraps. The
symptoms are increased drinking and diarrhea. Salt poisoning usually affects young birds.
Ammonia: High humidity may cause high levels of ammonia to be present in poultry sheds.
This is easily detected by smell and, if not removed, may lead to respiratory problems and
sometimes, severe conjunctivitis (ammonia burn).
If the litter in the shed is kept dry and clean and the shed is well ventilated, ammonia should not
be a problem.
Lead: Symptoms of lead poisoning are loss of appetite, drowsiness, paralysis, convulsions,
diarrhea and sudden death. Check the area for old paint products, motor oils, old batteries and
buckshot.
Plants: The seeds, fruit or leaves of some plants are poisonous at all times or at a specific stage
of growth. Poisons can be found in some garden plants and weeds, including oleander
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