Something people seem to never consider when they have eggs that are quitters at some point is breeder nutrition.
Regular chicken feed is good for egg laying but not really enough for viable vigorous chicks.
Also, many health problems in adult and growing birds can be nutrition related and shouldn't be treated with antibiotics.
Each day, I'll post about a specific nutritional deficiency and how it affects hatchability and viability of chicks.
Today's topic is Vitamin A deficiency from 'International Poultry Production's Poultry Health Bytes.
"Vitamin A
Vitamin A is deficient in most feedstuffs {but} can easily be toxic as a consequence of over
supplementation. Compared to wheat or sorghum based diets, corn based diets contain less
vitamin A and are more likely to cause deficiencies.
Vitamin A deficiency
In vitamin deficiency the epithelial basal cells differentiate into squamous cells, which may
become stratified and keratinised to form a hard, dry skin.
Vitamin A deficiency in the embryo causes an abnormal cardiovascular system, resulting in embryonic death in the first week of incubation. Any embryos which survive to hatching produce very weak chicks that soon die.
In growing chicks and poults, vitamin A deficiency results in reduced growth, depression, inappetence and increased mortality from secondary infections. In addition, unsteady gait and postural imbalance can occur. Other changes associated with vitamin A deficiency include epithelial damage in the mouth cavity, pharynx and gullet, periorbital oedema and caseous material under the eyelids accompanied by lachrymation. Vitamin A deficiencies can adversely affect development of the bursa of Fabricius and thymus and thereby impair normal immunity.
As a result of vitamin A storage in the liver it often takes 2-6 months for the signs of vitamin A
deficiency to occur in adult birds. Vitamin A deficient hens show weakness, weight loss, ruffled
feathers, a sharp drop in egg production, blood spots in eggs and an increased susceptibility to
infections. Eye changes similar to those previously described also occur and can result in
blindness. In vitamin A deficient layers an increased frequency of atretic ovarian follicles are
seen in birds exposed to a deficiency over 5-8 months.
Pathology
The first lesions are seen in the oesophagus (gullet) and pharynx where the epithelium is
replaced by keratinised epithelium. Small white nodules can be seen in the mouth, oesophagus
and pharynx as well as in the nasal cavities which enlarge as the deficiency progresses. This is
often accompanied by some ulceration.
On the basis of clinical signs and lesions it can be hard to differentiate infectious coryza,
infectious laryngotracheitis, fowlpox or infectious bronchitis from vitamin A deficiency.
Chronic vitamin A deficiency can result in kidney damage, which is usually followed by gout.
Treatment
Treatment is by vitamin A administration and, as its absorption is rapid, birds not in the
advanced stages of deficiency respond quickly to treatment."
I really can imagine that with some of those symptoms in growing and adult birds, many people would lunge at treating with antibiotics.