General poultry cages can be categorized into full阶梯 cages, half阶梯 cages, layered cages, mixed阶梯 cages, and flat cages based on their shape or assembly form.
Full-step laying hen cages, the cages on different levels do not overlap vertically. This allows the feces from each level to fall into the feces channel below, where it is then cleaned out of the henhouse by a ground scraper cleaning machine installed in the feces channel.
Semi-step nesting cages for laying hens, with part of the upper and lower cages overlapping, the overlap can reach 1/2 to 1/3 of the cage depth. The top mesh of the lower cage is designed at an angle for easy installation of manure boards, allowing the accumulated droppings on the upper level to fall into the dung trough below due to gravity after drying in the wind. Most brooding and breeding cages produced in China use this design. The semi-step nesting cages occupy less space and have a higher density of housing compared to full-step nesting cages.
Stacked layer hen cages, with each layer overlapping vertically. The bottom mesh of each cage layer features a horizontal manure collection system, which can be cleaned using a scraper manure removal machine or a conveyor belt manure removal machine, transporting the manure to one end of each row of cages, then transferred outside by a horizontal spiral scraper. Small-scale stacked cages can be manually cleaned. Feeding, watering, manure removal, and egg collection are easily mechanized. The advantages of stacked cage farming include high density of housing, typically 16-18 birds per cubic meter for three layers and 18-20 birds per cubic meter for four layers, reducing the construction investment per bird and high labor productivity. The disadvantages are poor ventilation between layers vertically, significant differences in environmental conditions among cage layers, and high requirements for chicken house environmental control.
Stacked and mixed laying hen cages, with the upper and lower cages staggered, and the middle and lower cages fully overlapped. The lower cages have manure boards above the top wire mesh, allowing for manual pushing of manure inward for dropping or using a mechanical scraper to clean.
Flat-layer laying hen cages, consisting of a single layer of cages, with two rows of cages installed back-to-back, sharing one feeding trough, one water trough, and one egg conveyor belt. Chicken droppings fall directly to the ground, and the drinking and cleaning equipment is the same as that for step cages. Flat-layer cages do not require corridors, so their density is higher than that of full-step cages. However, feeding, drinking, cleaning, and egg collection must all be mechanized, thus requiring reliable machinery and a heavy reliance on electricity. In the event of a power outage, the consequences could be severe.
