Prevention and treatment of fatigue in caged laying hens with standing difficulties in soft and thin eggs

Fatigue of caged laying hens, also known as osteoporosis of caged laying hens, often occurs during the peak period of egg production. If it is found in time and appropriate measures are taken, most of them will recover within 3-5 days. If it is found later, it will take about 20 days to recover, and some seriously paralyzed layers may die and cause losses.

Caged laying hens

First, symptoms: the disease first laid soft-shell eggs, thin-shell eggs, egg damage rate increased, but laying hens appetite, feathers are not changed. After that, there are difficulties in standing, bending claws and dyskinesia. In the later stage, the symptoms worsened gradually, and finally the laying hens were lame, unable to stand, paralyzed, sunken sternum, broken ribs, fragile wings and leg bones.

2. Etiology: (1) insufficient calcium content and imbalance of calcium and phosphorus in the diet of caged laying hens. (2) the overcomminuted stone powder and bone powder were absorbed and excreted quickly in the gastrointestinal tract of laying hens, resulting in low utilization rate of calcium. (3) the activity of caged laying hens is small, and the feeding and management is improper. (4) layers are invaded by parasites during the breeding period.

Third, prevention: (1) ensure full-price nutrition and strengthen scientific management to make the layers reach the best body weight and condition when they are sexually mature. (2) feeding special pre-production feed containing 2-3% calcium 2-4 weeks before laying, and switching to laying hen feed in time when the laying rate reaches 1%. (3) the calcium content in the feed of caged high-yield laying hens is not less than 3.5%, and the appropriate ratio of calcium to phosphorus is guaranteed, and more than 3200 international units of vitamin D are added to each kilogram of feed. (4) to provide laying hens with coarse stone powder or shell powder, which accounts for 1-2-3 of the total calcium. The calcium source particle is more than 0.75 mm, which can not only improve the utilization rate of calcium, but also avoid calcium graded precipitation. In the hot season, coarse calcium particles are evenly scattered into the trough every afternoon according to about 1% of feed consumption, which can not only provide sufficient calcium sources, but also stimulate the appetite of chickens and increase food intake. (5) Blood calcium monitoring should be done at ordinary times, and blood calcium test should be done in time when it is found that soft shell eggs are produced.

Fourth, treatment: when diseased chickens are found, pick them out in time, put them on the ground and raise them alone, and ensure that laying hens drink water and feed normally, and generally recover on their own in no more than one week. For the same group of chickens with low blood calcium, 2-3% coarse-grained calcium carbonate was added to the feed, and 2000 international units of vitamin D3 per kilogram of feed were added. After 2-3 weeks, the serum calcium of the chickens increased to the normal level, and the incidence decreased. The supplement of coarse calcium carbonate and vitamin D3 lasts about 1 month.