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'Well begun is half done' holds good in poultry production also, because a good start means a better bird. The first week of a chick's life is very crucial. To realize the genetic potentiality of today's broilers and layers, they need a good start and utmost care.
Obtaining a good quality chick is the first step towards achieving high profits. Chicks should have qualities such as uniformity, lively bright eyes, good plumage, and a plump body with high day-old weight.
Constant increase in daily growth, specially in broiler chicks, makes the lenght of the fattening period shorter, and today's birds eat less and produce more. To achieve this, the first few days of a chick's life are important because this is when the basis is laid for optimum growth and health. Immediately after hatching, all kinds of important changes occur in the chick. When a chick hatches out of an egg, 20% of its body weight consists of the remains of yolk. Though yolk provides the chick with sufficient nutrients for the first few days, the chick has to switch from digesting the yolk to digestion of solid feed. Furthermore, the digestive organs and liver develop in the first weeks of life and later, skeletal and muscular tissue mass increases. The intestine is virtually sterile and has to acquire its own native microflora. Pathogens pos a major challenge as they multiply at a much faster pace compared to normal microflora. Immune organs are yet to develop fully. All these factors make the first week very crucial.
Chick mortality during the early weeks poses a great economic challenge to the poultry farmer and is a matter of great concern. ECM is the result of many interrelated factors. Unless tackled carefully from different angles, viz. management, nutrition, disease control, etc., it is difficult to control Early Chick Mortality.
Causes of ECM:
There are many causes of Early Chick Mortality . Some important causes are:
Sticky embryos die during the last four days of incubation and about half the chicks die during the two or three days before hatching time. Congenital loco is lethal within a week of hatching and congenital tremor kills 90% of the affected chicks within a month. If the eggs from a control and a carrier flock are incubated under the same conditions, the maximum difference in hatching will be about 25%.
A) Brooding and Brooding temperature:
Brooding the chicks on the floor needs a 3-inch layer of clean dry litter. Sawdust and other fine litter material should be avoided to prevent excessive ltter consumption, which results in choking. Brooding on slippery surfaces like newspapaer or wood floors is not advisable as the lack of good traction may result in permanent leg damage. A chick guard 18-24 inches high and 6-10 lt. across is sufficient for 100 chicks.
High brooding temperatue causes:
Dehydration: The body of young chicks contain about 70% water. Continuous high temperature causes loss of water from the body and when this water loss reaches about 10% the chicks die due to dehydration.
Pasting: This is another problem of high brooding temperature wherein feces block the vent, Pasting ultimately results in death.
At the same time, Low brooding temperature causes:
Chilling or Brooding pneumonia: Temperature below normal lead to pneumonia in young chicks, in which the lungs turn blue
Smothering: Under low temperature chicks huddle together to maintain body temperature and this results in smothering and death.
Chilled chicks have smaller bursa compared to those undernormal tempearature. Proper brooding helps in absorption of yolk and prevents yolk-sac infection.
Prevention of temperature related problems: To prevent dehydration, pasting, chilling, and smothering, adjust the brooding room temperature 24 hours before putting the chicks in the brooding room and during the brooding period. Try to maintain normal temperature throughout the brooding period and in the entire brooding area.
B) Positioning and injuries:
Feed
poisoning: Fungal contaminated feed and toxic material in feed
causes feed poisoning .
Salt poisoning: Salt poisoning also causes mortality which
is due to excess salt in drinking water and feed.
Ammonia: Putting down curtains down all hours, accumulates
ammonia and it causes irritation of mucous membrane and eyes, low feed
consumption, reduced growth rate, loss of cilia in the trachea, hemorrhages
and death at level above 100 ppm, so its concentration should be less than
25 ppm.
Tannin or Litter poisoning: The ingestion of toxic material
like tannin in saw dust causes mortality.
Injuries: If chicks are not handled carefully during various
operations it causes injuries and death which are; sexing, vaccination,
dubbing, debeaking.
C) Relative Humidity:
High relative humidity
in brooding house causes the dampness of litter material which facilitate
the growth of micro organisms causing infections.
D) Predators :
If brooding houses are not properly constructed against predators they also
causes mortality, e.g. Rat, Dog, Cat etc.
E) Water: Water
play an important role in maintaining the health and performance of the birds.
It acts as a transport medium for nutrients and metabolic end products. It
helps in maintaining body temperature during hot weather. Water play an important
role in weight gain of broiler. Water is source of minerals like Na, Cl,
K etc.
F) Inadequate
floor, feeder and waterer spaces: Less floor space is another cause
of mortality in chicks as over crowding causes dampness of the litter material
which become a suitable site for the multiplication of micro organism,
causing, coccidiosis etc. Less feeder and waterer space creates competition
among chicks, they become weak and die out of starvation.
Yolk-sac is regarded as the nutritional source for the first 48-78 hours after hatching. Though it is a rich source of maternal antibodies and vitamins. It doesnot provide complete nutritiona. Use of nutritional supplements as early as possible can help in developing the intestines, immunity and general health. It is important to remember that early chick growth is determined by the itestines. Early intestinal development is one of the important factors controlling later potential growth. As this development is completed during the first few days, any mistake during this period can be disastrous for later productivity. A delay in placement by 24 hours would mean reduction by 50% in yolk-sac weight and body weight at 3-7 weeks, apart from early chick mortality. Use waterers that the young chick can reach, but not fall into. For larger flocks, a nipple watering system at an appropriate height works very well. Baby chicks, being curious, see the shining droplet on the nipple waterer, peck at it and thereby quickly learn to activate the waterers. Nipple height and placement are critical factors in averting Early Chick Mortality. If the nipple is beyond reach, chicks consume wet bedding material beneath the nipples, and unable to swallow the material, suffocate and die. The problem can be corrected lowering the nipples and increasing the number of nipples.
Feed: Feeders are to be placed close to the source of heat, but not directly under the lamp. Keep the feed fresh all the time. Feeding chicks with too much dusty feed on day one increases mortality due to clogging in the crop and suffocation. However, feeding larger grain particles, especially maize, causes 'crop bound' and lactic acidosis resulting in mortality. Accidental feeding for grower or layer mash is also dangerous as particle size is too large.
Vitamins: Severe deficiency of Vitamins (A,D,E & K) causes death, while minor deficiency causes cessation of growth, ruffled feather, lacrimation, rickets, encephalomalacia, exudative diathesis, anemia, etc. Similarly, severe deficiency of these vitamins (B-complex and C) causes death, while minor deficiency causes loss of weight, poor feathering, poor growth, dermatitis, perosis, nervous signs,anemia etc.
| Vitamin | Signs of deficiency |
| Vitamin D3 | Beak and claws soft and pliable, severe weakness of legs |
| Pantothenic Acid | Retards growth, ragged feather development, eyelids stick together, crusty scabs at the corner of mouth and eye |
| Vitamin A | Cessation of growth, drowsiness, ewakness, incoordination, emaciation, ruffled plumage |
| Folic Acid | Deficiency results in poor feathering, retardatin of growth and anemia |
| Vitamin E | Central nervous system disturbance, subcutaneous edema, muscle abnormalities |
| Riboflavin | Diarrhoea, retardation of growth, leg paralysis |
| Vitamin B12 | Retarded growth, gizzard erosion, fatty heart, liver and kidneys may occur, along with poor feathering |
All these vital nutrients are important not only for growth, but also for body resistance. Amino acids especially Arginine, Threonine and Methionine are very important for development of the immune system. Essential fatty acids such as Omega 3 and Omega 6 positively influence immune response.
Disease Causes:Infectious diseases play a crucial role in the life of a chick imosing a major limiting factor on intensive production programs all over the world and more so in tropical countries. The economic losses may be reflected in heavy mortality or reduced meat and egg production. Early Chick Mortality may be caused by bacterial infections, showing lesions of yolk-sac infection. Air sacculitis, congested lungs and liver etc.
Many infections transmitted fromparents vertically and some of them could be hatchery-borne, e.g. Salmonella, Mycoplasma, Adenoviral infections. Even eggs contaminated with microorganisms play a significant role in poultry production pathology - E. coli, Pseudomonas and Staphylococcus. Microorganisms cause increased mortality of embryos, lower hatchability and increased early chick mortality.
Omphalitis: This bacerial disease affects chicks during and after hatching, navel infection characterized by inflammed skin in the navel area, soft, flabby and distended abdomen, vent pasting and foul smell on carcass opening, due to unabsorbed yolk.
Pullorum: An acute infectious and fatal bacterial disease in chicks characterized by ruffled feather, white diarrhoea, labored breathing, chiping and death.
Salmonella: A group of acute rapidly-spreading diseases affecting all ages and characterized by rise in body temperature, septicemia, omphalitis, hepatitis, enlargement of spleen, arthritis and death.
Colibacillosis: An acute septicemia disease caused by E.Coli affecting all ages and characterized by involvement of all systems, poor feed conversion and death.
Metabolic Problems: Recently, reference has been made to the possible role of low levels of glucose in trigerring some of the non-specific early mortality problems noted in chicks. Birds that are hatched early or from small eggs may have reduced blood glucose levels when taken from the hatchery. Chicks are subjected to various procedures in the hatchery, each adding to the stress load on the birds. As the stress load increases, the demand for blood glucose also increases, with the result that adrenalin is secreted and glycogen reserves are mobilized from the body. Thus in a situation where the chick is without feed for 24 to 48 hours, low blood glucose levels can result. Birds that hatch early use up their glucose reserves while in the hatchery unlike those that hatch later. When glucose reserves are depleted, the chicks are in a precarious state with respect to their ability to handle stress. Low blood glucose has been shown to be associated with several of the non-specific early mortality problems reported in chicks. Reduced pH values associated with low blood glucose will obviously result in changes in acid-base balance, a condition which is receiving increased attention when investigating factors leading to SDS and Ascites.
Perhaps it is time for
the industry to re-link some of the early handling, feeding and management
programs for the young chick.
'Prevention is better than cure' holds good even for ECM. ECM control needs a multifaceted approach in terms of management, nutrition and disease prevention.
