Laying hens need to be kept for about 72 weeks from hatching to elimination, so laying hens need to be kept for 500 days. According to the growth characteristics and laws of laying hens, laying hens can be divided into several feeding and management stages. In order to give full play to the high-yield performance of laying hens and obtain the best feeding benefits, in addition to the variety factors, the key lies in understanding and mastering the needs of laying hens at different growth stages and the technical points of feeding management.
First, the stage division
Laying hens can generally be divided into three stages: brooding, rearing and laying eggs.
1. In the brooding stage, modern laying hens often take 0-8 weeks as the brooding stage. The experiment shows that 8-week brooding is more beneficial to the cultivation of backup laying hens and the development of laying potential than 6-week brooding.
2. The breeding stage refers to the period from the completion of brooding to prenatal, that is, 9-20 weeks old. The breeding period can be subdivided into three parts: 9 ~ 12 weeks in the prophase, 0/3 ~18 weeks in the anaphase, and 0/9 ~ 20 weeks before spawning.
3. The laying stage refers to the stage from 5% laying rate to elimination. Generally from 2 1 week to 72 weeks. The laying stage can be subdivided into 2 1 ~ 42 weeks before laying, 43 ~ 60 weeks in the middle of laying, and 6 1 week in the late of laying (about 72 weeks).
Second, the technical points of feeding and custody at different stages
1.0 ~ 8 weeks old feeding management points during brooding period
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(2) Providing an indoor environment suitable for the growth and development of chicks: The most striking feature of the brooding stage is the strict requirements on the indoor environment temperature. In other words, the indoor temperature is the key factor for the success or failure of brooding. Generally, the greenhouse temperature should be kept at 34 ~ 36℃ day and night within 1 week, and then decrease by 2℃ every week until it is constant at 22 ~ 24℃. The indoor relative humidity should be kept at 65% ~ 70% within 2 weeks, and gradually decreased to 55% ~ 60% from 3 weeks.
(3) Drinking water and opening food: chicks are fed with water after entering the house, and then fed after 2-3 hours. 1 week, adding 5% glucose to drinking water, multi-dimensional or rapid electrolytic supplement, salt supplement, etc. Its main functions are health care, anti-stress and facilitating meconium excretion. Chicken's demand for water far exceeds feed, so it is necessary to ensure continuous water supply and clean water quality, and the water should be replaced in time overnight. Add a small amount frequently in the first week to avoid indigestion and waste of feed.
(4) Feed nutrition: Although chicks eat less, they have higher requirements on feed quality, so they should provide complete compound feed with high raw material quality, strong palatability and easy digestion and absorption. Dietary nutritional level: crude protein 19% ~ 20%, metabolic energy 1 1.7 MJ/kg, calcium 0.9%, total phosphorus 0.60% ~ 0.65%.
(5) Illumination time and intensity: 23-24 hours in the first 3 days, reduced to 65,438+08 hours on the 4th-7th day, and 65,438+02 hours from the 2nd week to the end of brooding. The light intensity is strong first and then weak. At 1 week, use 1 60-watt bulb every 20 square meters, and replace 40 watts after 1 week. The light bulb is 2.0 ~ 2.2 meters away from the chicken bed (or ground).
(6) Beak-breaking: Beak-breaking is an indispensable work in the feeding process of laying hens, which is usually carried out within 7-9 days. It can save feed consumption and reduce pecking addiction, but if it is not handled properly, it will cause bleeding death or lifelong disability. Add double amount of vitamin K and vitamin C to drinking water or feed 3 days before and on the same day.
Key points of feeding management in the growth period of 2.9 ~ 20 weeks.
If the key to the brooding stage is to control the greenhouse temperature and ensure the feed quality, then the key to the brooding stage is to control the light time and weight.
(1) prophase (9 ~ 12 weeks):
① timely grouping and keeping proper feeding density: the growth period is the fastest stage of weight gain, and adjusting feeding density is beneficial to population growth and uniformity, which can reduce the occurrence of diseases. 12 ~ 15/m2 in early breeding period and 8 ~ 10/m2 in late breeding period.
(2) Pre-breeding period is the continuation of brooding period, and there is still a high demand for feed nutrition. Many chicken farmers often neglect feeding management during the breeding period, resulting in irreparable losses after opening the pen. In the early growth stage, the dietary crude protein should be 15.5% ~ 16.0%, and the metabolic energy should not be lower than 1 1.5 MJ/kg, which is the same for other chicks.
(3) The lighting time should be controlled at about 10 hour, and the lighting window should be blocked by colored curtains to avoid excessive light.
(2) Late growth stage (13 ~ 18 weeks):
① Strictly control the lighting time: After the backup hen entered 13 weeks, its body shape, appearance and reproductive physiology were obviously changed, mainly manifested in active gonads, obvious ovarian function development and accelerated bone growth and development, which is another key period for the backup hen cultivation. In order to avoid the influence of precocious puberty on egg laying performance, the illumination time must be strictly controlled within 10 hour.
② Weight control and dietary nutrition level adjustment: In general, prevention of overweight should be given priority to, and towns should adopt quality-limited feeding, so that the crude protein level of rations should not exceed 14%, or the total intake should be limited. If the weight is low, it is necessary to improve the nutritional level of the diet, extend the feeding time and ensure that the cage weight is within the normal range.
③ deworming: generally, one-off deworming should be carried out within 65,438+0.7 weeks before caging. Levamisole can be used as an insect repellent, and the dosage should be determined according to the number and average weight of backup laying hens. After the tablets are crushed, they are gradually mixed into the daily feed of backup chickens and allowed to eat freely. It is best to clean the feed before feeding, stop feeding for a few hours, and let the chickens be hungry.
(3) Prenatal transition period (19 ~ 20 weeks old): After careful cultivation for 18 weeks, the backup layers have completed the growth of bones and the full development of reproductive systems such as ovaries, and have been transferred to the laying hen house. At this time, the low calcium level will be increased from about 0.9% to 2.0% ~ 2.5% during the laying period. After two weeks of transition preparation, sufficient nutrients are reserved for the laying period, so that the backup laying hens can enter the laying peak period quickly and neatly.
During the transition period, backup laying hens are faced with the stress brought by the changes in henhouse environment, diet composition, breeders, feeding methods and physiology. In management, we must pay attention to keeping the environment of the henhouse quiet and hygienic, the staff should go into battle lightly, minimize all kinds of external stimuli, and add anti-stress drugs such as vitamin C and electrolytic multivitamins to the drinking water.
Before 18 weeks old, the light time can only be shortened, but not extended. After entering the prenatal transition period, the light time can be gradually increased, but not too fast. The transition period can be extended by 15 minutes every day.
3. Key points of feeding management in laying period
(1) Pre-laying period (27 ~ 42 weeks old): The so-called pre-laying period mainly includes the rising period and peak period of laying. Generally speaking, it starts from 2 1 week, and officially enters the laying period. After 6-7 weeks of rapid growth, it can reach the peak of laying (the laying rate is over 90%). At this time, the laying hens are sensitive and delicate, and their disease resistance is weak, so they need to be carefully cared for.
① A diet with high nutritional level is required. From the laying rate of 5% (2 1 week), the peak diet was given. At this time, the egg production rate rose linearly and the weight continued to increase. This feeding method, in which nutrition reaches its peak before the laying rate, is beneficial to the storage of nutrients and the maturity of the body of laying hens, to the display of high-yield genetic potential and to the extension of the laying peak period. The pre-laying period is the most critical period for newborn hens. The management requirements are strict and meticulous, but the nutritional needs must be met first. Dietary crude protein 18% ~ 19%, metabolic energy 1 1.7 MJ/kg, calcium 3.3% ~ 3.6%, available phosphorus not less than 0.4%. It is particularly important to ensure that the proportion of various amino acids in the diet is balanced and contains enough vitamins, mineral salts and enzymes, otherwise it will be difficult to maintain it for a long time during the peak period.
② Strive to create a comfortable spawning environment. It mainly includes indoor temperature (13 ~ 23℃), relative humidity (55% ~ 65%), air quality, ventilation and lighting, feed quality and other comprehensive factors.
③ Strictly determine the reasonable lighting time. With the increase of egg laying rate after opening the pen, the light time should be gradually extended (only extended without shortening) until the yield peak (27-28 weeks old). The lighting time should be kept constant at 16.0- 16.5 hours, and the time of turning on and off the lights every day should be strictly fixed and not changed at will.
(4) Keep the drinking water supply clean and sanitary, and do not stop drinking water during laying to prevent non-working personnel from entering. Staff should be careful when operating, don't change clothes casually, and try to avoid all stress reactions caused by external stimuli. If the feeding management is improper, the egg laying rate will decrease due to adversity during the rising period of egg laying, and it will be difficult to recover.
(2) Mid-laying period (43 ~ 60 weeks old): This is the period when the laying rate gradually decreases after the peak laying period. The average laying rate of excellent high-yield laying hens can still be maintained at a high level of over 80%. How to keep the egg production rate decreasing steadily is the key to feeding management at this stage.
First of all, we should have a correct understanding in thought, and we must never relax the management level or blindly reduce the nutritional level of the diet just because the egg production peak has passed, just like in the early stage of laying.
(2) At this time, the feathers of laying hens gradually fell off, and the tail beams, walls and windows of the henhouse were covered with dust and dirt, and the air quality in the henhouse was worse than that in the early laying period. Therefore, it is more necessary to strengthen the management and rectification of indoor environmental sanitation, create a quiet, hygienic, well-ventilated living and production environment with appropriate temperature and humidity, and reduce the occurrence of epidemic diseases.
③ Proper reduction of crude protein and energy levels and proper supplementation of multivitamins will help chickens recover from fatigue caused by high yield and maintain a high level of laying eggs.
(3) Late laying period (6 1 ~ 72 weeks): In terms of productivity and reproductive physiology of laying hens, it can be regarded as late laying period after 60 weeks. At this time, the group egg laying rate has been at a low level (about 70%), and it is difficult to change even if a high level of diet is supplied. Due to the degradation of physiological function of chickens, the absorption and utilization ability of calcium is reduced. Therefore, the nutritional level of diet should be adjusted to be characterized by high energy (metabolic energy 1 1.7 MJ/kg or more), high calcium (calcium content 3.4% ~ 3.8%) and low protein (14.0% ~ 14.5%).
In management, the illumination time can be extended by 0.5 ~ 1.0 hour to enhance the stimulation of hen gonad activity, thus increasing the laying intensity, and at the same time, low-yield chickens can be eliminated at any time.
Three. Daily health management and immunization
In order to make the laying hens grow normally for 500 days, improve the survival rate and laying rate and reduce the mortality rate. In addition to the above-mentioned feeding management points, we should also do a good job in daily health management and immunization.
1. Strengthen daily health management
(1) Improve and perfect the health and epidemic prevention work system, with the responsibility to the people and strict implementation.
② Keep the environment inside and outside the henhouse clean, and clean and disinfect it frequently. Remove feces regularly, once a day during the laying period, and 2 ~ 3 times a week during the brooding period and breeding period according to the specific situation.
(3) Insist on disinfection with chickens. Under normal circumstances, twice a week in Shanghai, the disinfectant should be replaced alternately.
(4) The water dispenser shall be soaked and washed with disinfectant every day 1 time, and must be scrubbed before use. The bucket is cleaned with disinfectant 1 time every week. If V-shaped tanks are used in captivity, they must be carefully scrubbed 1 time every day and disinfected with disinfectant 1 time for 1 week.
⑤ In the egg laying stage, the light bulbs should be wiped every day, and the discarded light bulbs should be replaced in time.
⑥ Observe the mental state, eating, drinking and feces of the chickens every day, and pick up the dead chickens and burn them or bury them deeply in time. Eliminate sick, weak and disabled chickens in time, and make daily work records.
2. Immunization
Immunization is an important means to prevent the occurrence and spread of serious infectious diseases, but no immunization program can be used universally. Before entering the chicken, it is necessary to formulate an immunization program that conforms to the characteristics and laws of endemic diseases and vaccinate on time.