Effective measures to reduce chick mortality in white-feathered broiler farming

Chicks at 0—4 weeks of age have an imperfect thermoregulatory function, high nutritional requirements, and weak resistance to disease, and often die from various diseases. Preventive measures should be taken to reduce mortality and improve brooding survival rates.

(1) Preventing pullorum disease in chicks: analysis of the causes of chick mortality shows that, where breeder chickens have not been quarantined for pullorum disease, the mortality rate of chicks infected with pullorum disease accounts for more than 50% of total chick mortality, and among chicks that died of pullorum disease, 87.9% died in the first week of brooding. This is because during incubation, if disinfection at each stage is not strict, infection with this disease can occur at the hatching egg or chicken embryo stage. Methods for preventing pullorum disease include, in addition to regular quarantine testing of breeder chickens for pullorum, strict culling of positive birds, and fumigation disinfection of hatching eggs and chicks, the addition of antibacterial drugs to the feed before 3 weeks of age, with the following drugs as references. ① Robenidine at 0.0033% mixed into feed, or furazolidone at 0.02% mixed into feed for prevention. ② After onset of the disease, increase furazolidone to 0.04% and feed continuously for 7 days, which can significantly reduce the mortality rate of sick chicks. ③ Oxytetracycline, chlortetracycline or tetracycline mixed into feed at 0.02% and fed continuously for 7 days. ④ Sulfadiazine or sulfamerazine mixed into feed at 0.05% and used continuously for 3—5 days.

(2) Strict disinfection to prevent navel infection: if the incubator, brooding room and various tools are not strictly disinfected, various bacteria such as Escherichia coli, Pseudomonas and Salmonella may be present, and may invade the yolk sac through a poorly closed navel opening, causing infection and inflammation, namely omphalitis. This manifests as abdominal distension, swollen and moist navel, and an unpleasant odor, and death may occur from toxemia. Necropsy reveals unabsorbed yolk and an enlarged yolk sac, with the yolk appearing watery or brownish watery, and the yolk sac rupturing easily. Measures to prevent this disease are strict disinfection of the brooding room and tools; staff entering the hatching room and brooding room and before operations must undergo disinfection treatment, and strict isolation measures must be adopted to ensure normal brooding temperature; once the yolk is normally absorbed, the chance of infection can be greatly reduced, and human cross-infection can also be prevented, with morbidity and mortality greatly reduced.

(3) Strengthen epidemic prevention systems: chicks are most susceptible to acute infectious diseases such as Marek's disease and Newcastle disease, and once these spread, they are very difficult to control and may cause total loss. Therefore, following the principle of prevention first, epidemic prevention systems and immunization programs should be formulated and meticulously implemented.

(4) Drink water early to prevent dehydration: among chick deaths, 9.93% die of dehydration, mostly because injection of vaccines, transport and some preparatory work cause too long a time from hatching to first drinking, resulting in excessive body water loss; in addition, when water is provided the chicks do not know how to drink, or drinking is not timely, and the weak ones collapse and die. Chicks that die of dehydration in the first week can account for 64.9% of total dehydration deaths. Therefore, drinking should be started as early as possible. To ensure that chicks drink water, chicks at 1—3 days of age must have 23—24 hours of light time, with light intensity reaching 15 lux, so that chicks become familiar with the position of the drinker as early as possible, and water should be given before feed. Drinking water must not be interrupted at ordinary times, especially within 2 weeks of age, which is even more important.

(5) Keep the brooding house temperature stable and humidity appropriate: to improve the brooding survival rate, chicks must be provided with suitable environmental conditions. Provide suitable temperature and keep it stable, with little temperature variation; where coal stoves are used for heating, the nighttime room temperature is very important. Avoid the occurrence of chicks being killed by heat, freezing or crushing.

(6) Strictly prevent death from poisoning: when using various drugs to treat and prevent diseases, the dosage must be calculated correctly to avoid overdose causing drug poisoning. When treating a large flock, drugs and feed must be mixed evenly; first mix with a small amount of powdered feed, then gradually expand at a ratio of 1:10 to the specified content. When administering drugs in drinking water, the tablets must first be fully crushed and ground fine, then dissolved in water, to avoid drugs settling at the bottom of the drinker and causing excessive intake.