Study On Spatial Environmental Building And Healthy Raising Technologies In Pig Loose Housing System

Modern pigs are more sensitive to environmental stress, significantly reducing the environmental tolerance. Limited space, barren environment, poor comfort and inappropriate environmental control methods all have serious influences on pigs’ health and potential productivity, resulting in inefficient production, high raising risks and obvious market fluctuation which all go against to the industry’s sustainable development. This study started with pigs’ spatial environmental requirements, then analyzed spatial environmental conditions under different housing models and investigated the relationship between spatial environmental constitution and pigs’ spatial location, environmental stress and behavioral expression under diffident group sizes. The effects of setting welfare facilities and local environmental control technology on spatial environmental configuration were studied. It also presented new process technologies and spatial environmental design methods. These studies all contribute to providing theoretical basis and technical support for the promotion of production mode and the sustainable development of livestock production in China. This study provides the following findings:(1) The relationship between the housing environment and the process model with pigs’ physiology, behaviors, health, growth, and production performance was described systematically and comprehensively. Process models and technologies for healthy pig housing were first studied from the point of pigs’ spatial environmental requirements. Parameter determinations of group size, raising density, economic pen area, pen dimension, and pen unit setting were also performed. These findings contribute to providing theoretical basis for pig housing process model design.(2) Spatial environmental constitutions and characteristics of engineering technologies in large/small group housing system for sows, farrowing pen system for lactation sows and loose housing system for weaned piglets and finisher pigs were compared and analyzed. Experiments on the applications of precision feeding, local environmental control and stress resistance facilities were also conducted. These findings contribute to providing technical support for the effective conduction of the healthy pig housing process model and the optimization of its equipment and facilities.(3) Group housing is benefit for pig’s behavior expression, building harmonious social relations, and improving reproductive performance. Small group housing system with more than8pigs could meet their space requirements, reducing fighting behaviors and the social stress at the beginning of group mixing. Local breeds had lower social class and were the underdog in the fight after mixing with modern pigs, and pigs in higher class had advantages on space occupying. Higher reproductive performance indexes including conception rate, farrowing rate, litter size were found in large group precision feeding system than in single pen housing system, breeding diseases and limb-and-hoof diseases incidences were respectively84%and50%lower in large group precision feeding system than in single pen housing system, both thanks to better social environment and bigger activity space.(4) The spatial environmental constitutions by3different farrowing pens and2different piglets conservation boxes were compared. The freedom farrowing pen could provide more space for sows and reduce the probability that piglets were pressed to dead by sows. The curtains could improve the local environment of conservation box and are also conducive to free access. These facilities are helpful for sow’s recovering from delivery, reproductive performance improvement, and producing healthy piglets.(5) Welfare facilities played an important role on the spatial environmental constitution, the function orientation of each area in the pen, and the utilization of equipment. Rich spatial environment could increase pigs’ feeding time and reduce their lying time and detention time in eliminative area. Pigs in rich spatial environment were more active and change their activity more frequently. A good spatial environmental configuration for better behavior expression could be formed with2or more welfare facilities, resulting in improving5%-10%of daily gain and reducing3%-13%of food consumption.