Key Technical Points for the Feeding and Management of Free-Range Laying Hens on Sloping Land

The laying period of laying hens is broadly divided into three stages: early, middle and late. 1. Early laying period, from the first egg laid until the laying rate reaches 50%, i.e. the date when the whole flock starts laying, generally 20-24 weeks of age; 2. Mid laying period, the peak laying period when the laying rate rises from 50% to over 90%, then is maintained at 80%, generally 25-42 weeks of age; 3. Late laying period, when the laying rate falls below 80%, generally 43-72 weeks of age. Feeding laying hens requires balanced supplementary feeding, with supplementary feed given three or four times a day in the morning, midday and evening.
1. Key points of feeding and management in the early laying period
The early laying period is the most important stage in the development of laying hens. It is the stage when the birds are basically sexually mature while their bodies are not yet fully mature and are gradually maturing. On the one hand they must grow their bodies and gain weight, and on the other hand they must rapidly develop their reproductive system, in preparation for entering the adult laying period.
(1) Preparation before laying: prepare the laying hen house and ensure water and electricity facilities are complete. Carry out a thorough deworming before laying. For external parasites such as mites and lice, spraying medication may be used; for internal parasites, albendazole may be given orally at 20-30 mg/kg body weight, or avermectin (chongkexing) mixed into the feed. Remove weak chickens to keep the flock uniform. Carry out intramuscular immunization with a trivalent inactivated oil vaccine of Newcastle disease + egg drop syndrome + infectious bronchitis.
Selection of breeding roosters: breeding roosters should be healthy and lively, well developed, with bright red combs, obvious secondary sexual characteristics, and a strong build, and should meet the breed standard requirements. The ratio of male to female breeding chickens should be adjusted to 1:12-15, with males and females kept together for natural mating. Commercial laying hens do not require roosters to be kept.
Feed formula for laying hens before laying (15-20 weeks of age): rice or rice bran 98.2, limestone powder 1.4, salt 0.3, poultry multivitamin 0.1, plus insects.
(2) Controlling the start of laying: prevent early maturity. Early maturity (laying too early) will lead to early aging and instead reduce laying performance. Before laying, the protein and energy levels in the feed should be restricted, and the light period is best controlled within 10 hours, without artificial lighting. Promote the start of laying at the right time; the start of laying should be controlled to meet the requirements of the breed's production performance, and it should also not be affected by feed nutrient levels being unable to keep up and thus affect timely laying.
(3) Feed supplementation matching the daily increase in laying: after the first eggs appear, the laying rate gradually rises, and rises quickly, and egg weight also increases day by day. During this period the ovaries and secondary sexual characteristics (comb, wattles) of the chickens develop rapidly, and feed intake increases markedly, so they must be allowed to feed freely to meet their nutritional needs. In this situation, if nutrition cannot keep up, it will not only delay the development of the chickens but also prevent their laying performance from being fully exerted, so the highest laying level cannot be reached and the peak laying period will also be short. The feed nutrient level should be raised, and the amount fed should be gradually increased.
Feed formula for laying hens with a laying rate of 65-80% in the early laying period: soybean meal 18, corn 51.6, rice bran or rice 20, limestone powder 9, calcium hydrogen phosphate 1, salt 0.3, poultry multivitamin 0.1, plus earthworms and insects.
2. Feeding and management in the mid laying period
The mid laying period is the period when the laying rate rises rapidly and is at the peak laying stage. The purpose of feeding and management in the mid laying period is to maximize the peak laying rate and prolong the duration of the peak. After the laying rate reaches 50%, the peak is reached after 3-4 weeks. The peak laying period is the golden period of laying, and strengthening feeding and management allows the chickens to fully realize their genetic potential and reach the ideal laying level. For high-quality laying hens, under good feeding and management conditions, a laying rate of over 80% can be maintained for 20-25 weeks or even longer, and a laying rate of over 90% can be maintained for about 10 weeks.
During the peak laying period, all stressful factors must be avoided. Laying hens at peak laying are particularly sensitive to various stressful factors, and any disturbance will inevitably affect laying. Once the laying rate drops, it is difficult to restore, which will bring huge economic losses to the chicken farm. The following points should be achieved:
(1) Except for the keepers of the house, no other personnel are allowed to enter the chicken house;
(2) The keepers' clothing should remain the same color every day; changing clothes or colors can easily cause flock panic;
(3) There must be no interruption of feed, water or electricity;
(4) The house temperature must not be too high or too low. The most suitable temperature for laying hens is around 20°C; a room temperature of 13-25°C does not affect laying performance; in winter it is best to keep it above 10°C, and in summer it is best to keep it below 29°C;
(5) Avoid noise;
(6) The feed should be stable and not changed lightly, nutritionally complete and adequate, and moldy feed must be strictly avoided; increase the number of feedings and increase the amount of feed;
(7) Gradually increase lighting. During the peak laying period, ensure a light period of more than 14 hours. In summer, when the natural light period is longer, artificially supplement light by 30 minutes per week after the peak laying period; in winter, when the natural light period is shorter, after the start of laying, when the laying rate reaches 50%, artificial supplementary lighting should be given, increasing by 30 minutes per week until the natural light plus artificial light period reaches 17 hours, and it must not be extended without limit. During the laying period, the light period can only be extended, not shortened. Light intensity should be kept stable, with no change in strength. A light intensity of 6-10 LX (lux) is suitable, generally 2.5 watts per square meter. Install 40-60 watt incandescent bulbs or 15-20 watt fluorescent lamps in the chicken house, generally with a lamp height of 2 m and a lamp spacing of 4 m. Weak red light is beneficial to laying.
(8) Maintain air circulation in the house and keep the house clean and sanitary;
(9) Do a good job of disease prevention and control. Administer medication for one week every 4-5 weeks, adding antibiotics such as norfloxacin, ciprofloxacin, gentamicin, etc. to the feed or drinking water to prevent colibacillosis, salmonellosis, enteritis, etc.; additionally add 1 times the amount of multivitamins to the feed to meet the laying needs of the chickens, reduce various stress reactions, and improve resistance to various diseases; adhere to the system of disinfecting with the chickens present and environmental disinfection to prevent the introduction of disease.
(10) Reference feed formula for the peak laying period: soybean meal 22, corn 51.6, rice bran or rice 16, limestone powder 9, calcium hydrogen phosphate 1, salt 0.3, multivitamin 0.1, plus earthworms and insects. Feed changes must have a 7-day transition period.
3. Feeding and management in the late laying period
After a period of peak laying, as the age in days increases, the laying function of laying hens gradually declines and the laying rate slowly decreases. At this time, according to the decline in the laying rate, the feed should be appropriately adjusted, the feed nutrient composition appropriately adjusted, and the protein content reduced. For feeding and management measures, refer to those for the mid laying period. Gradually increase lighting, extending by 30 minutes per week, with a maximum light period of 17 hours. Feed changes must have a 7-day transition period.
Reference feed formula: soybean meal 18, corn 51.6, rice bran or rice 20, limestone powder 9, calcium hydrogen phosphate 1, salt 0.3, multivitamin 0.1, plus earthworms and insects.