The laying cycle of a chicken flock usually covers a span of 12 months. Egg production begins when the bird reaches about 18 to 22 weeks of age depending on the breed and season. Flock production rises sharply and reaches a peak of about 90 percent at the sixth or eighth week from day they started laying. Production then declines to about 65 percent after 12 months of laying.
There are some instances where farmers have witnessed their flock suddenly dropping their egg production to even less than 40 percent before the 12 months laying period. There are a number of factors that can explain such scenarios including non infectious and infectious causes.
Non infectious causes for a sudden drop in flock’s laying capacities include improper nutrition where the flocks are not fed on a proper balanced diet to sustain maximum egg production over time. Inadequate levels of energy, protein or calcium can cause a drop in egg production. The nutrition imbalance may result into oviduct prolapsed which mainly occurs when a bird is too fat or an egg is too large and he bird’s reproductive tract is expelled with the egg. Prolapse causes permanent damage to the hen and is fatal in some cases.
Toxic levels of salt given to birds can also cause a sudden drop of egg production. Birds require a sensitive balance between necessary and toxic levels of salt. Excess dietary salt intake readily causes wet dropping and wet litter. In addition, Mycotoxins in form of moulds that are ingested by the birds especially the commonly known aflatoxin can reduce egg production instantly. They interfere with absorption of certain nutrients and also have some hormones which affect the laying cycle of the hens.
There are also management mistakes that can prove to be costly to a poultry farmer reducing the egg production capacity instantly. For instance if the flock is out of feeds and water for several hours then automatically their laying cycle is interrupted.
Inadequate day length and high temperatures also contribute to the inconsistent egg production. Hens need about 14 hours of day length to maintain egg production. The intensity of light should be sufficient to allow a person to read newspaper at bird level. High environmental temperatures pose severe problems for all types of poultry. Feed consumption, egg production, egg size and hatchability are all adversely affected under conditions of severe heat stress.
Infectious causes for a drop in egg production are mainly diseases and parasitical attacks. These may include Ector parasites like fowl mite, lice and fleas. Endo parasites include roundworm, tape worms, gape worms among others. Main diseases that result into a drop of egg production and some instances death of the hens include fowl pox, coccidiosis, infectious bronchitis, Newcastle, bird flu and fowl cholera.