Effect Of Different Ventilation Modes On Pig Performance

The environment of the pig house has a very important impact on the growth and health of the pig.Wenshi is the largest pig raising enterprise in China.Its branches are spread over more than 20 provinces across the country,especially the different production management modes such as“company+farmer”,“company+family farm”,“company+breeding community”.The farms distributed in various places not only have a variety of pig house types and management modes,but also have different production benefits.In view of the significant impact of the ventilation mode of the pig house on the environment of the pig house,in order to analyze and compare the environmental factors in the pig house with different ventilation modes and the difference in pig production performance,this study is based on the Wenzhou animal husbandry in Wenzhou.Co.,Ltd.is a pig house with two different ventilation modes（longitudinal negative pressure ventilation,lateral negative pressure ventilation after air outlet）,and measures the environmental factor indicators（including temperature,air pressure,humidity,ventilation,ammonia concentration）in the two pig houses.hydrogen sulfide concentration,etc.),and test the pig’s production performance and serum biochemical indicators,analyze and compare the impact of different ventilation modes in the pig house on pig performance,in order to further optimize the design of pig houses in different areas and Management measures provide a reference.After preliminary research and preparation,the experiment was conducted in Guoyang County,Anhui Province from mid-June 20th to the end of December.The pigs in the first ventilation mode（longitudinal negative pressure ventilation）are called traditional pig houses in the Wenshi Group（designed and built by Wen’s Group）,and the second ventilation mode（horizontal negative pressure ventilation after the winds are discharged）It is called a pig house（designed and built by Qingdao Co.,Ltd.）.To this end,the test is divided into two groups:the traditional pig house group and the pie group.For each group of three pig houses,the number of weaned piglets（Duroc×Landrace×Yorkshire）in each pig house is 600-1300 heads（according to the actual feeding amount of different pig houses）.The feeding and management methods of pigs were carried out in accordance with the feeding management regulations of Anhui Wuzhou Wenshi Animal Husbandry Co.,Ltd.The trial period begins with the piglet conservation and ends with the fattening pig.During the test,environmental factors,blood samples of pigs,and production performance indicators such as pig’s market weight,feed-to-meat ratio,and daily gain were collected.When collecting environmental factors,three pig houses were selected for each group,and each pig house was selected with five sampling points according to the five-point method,starting at 9:00 am on the sampling day.The total number of samplings was 4,which were40 to 50 days old and 70 to 80 days old for weaned pigs,110 to 120 days old and 170 to180 days old for finishing pigs.When collecting blood samples,pigs of 50 days old and180 days old were selected,and 54 pigs（18 heads per pig house）were randomly selected from each group.5-10 ml of blood was collected from the anterior vena cava,and serum was prepared for storage.Serum total protein,albumin,globulin,urea nitrogen,glucose,triglycerides and total cholesterol were measured.Production performance indicators such as market weight,feed-to-meat ratio,and daily gain of test pigs are provided by the company’s sales department.Research indicates:1.The use of horizontal and negative pressure ventilation in the trenches is as high as the initial construction cost of the pig house group,but the infrastructure in the pig house is more perfect,the average cost per pig is lower,and no fuel is used in the breeding process,which is more than the traditional pig house group.energy saving.The breeding density is1.5 to 1.7 times higher than that of traditional pig houses,which fully reflects the high-efficiency production brought about by intensive farming.2.The horizontal air-pressure ventilation mode of the sloping and horizontal negative pressure ventilation mode is balanced,and it is superior to the traditional pig house adopting the longitudinal ventilation mode,which is reflected in the ammonia concentration and carbon dioxide concentration in the pig house during the whole growth period of the pig.The concentration of hydrogen sulfide and the total number of colonies are smaller than those of the traditional pig house group.It is suggested that this kind of ventilation method is more stable to the internal environment control of the barn,which is conducive to the balance of population growth.3.The detection of serum-related metabolic indicators in weaned piglets during the nursery period showed that the serum albumin content of the weaned piglets fed by the pig group was significantly lower than that of the piglets kept in the traditional pig house,and the serum globulin content was significantly higher than that.In the piglets raised in traditional pig houses,the above results suggest that the feeding area of piglets such as pig houses should be appropriately increased during the feeding process of weaned piglets to reduce the adverse effects of density stress.4.The environmental factor correlation test in the conservation stage shows that the humidity of the pig house group is moderately negatively correlated with the CO₂ concentration;the CO₂ concentration of the traditional pig house group is moderately negatively correlated with the total number of colonies;the temperature of the two pig houses and other environments The factors are moderately or weakly correlated;indicating that the temperature in the pig house can affect the evaluation of other gases.The correlation between the body weight measured by the pig house and the environmental factors of the barn shows that the NH₃ and H₂S content in the pig house are weakly positively correlated with the weight of the former segment and the interrupted fattening pig,respectively.Patterns such as the pig’s various environmental factors are less correlated with changes in body weight.The analysis results of the traditional pig house also showed that the environmental factors of the traditional pig house with longitudinal negative pressure ventilation were less correlated with the change of body weight except for the H₂S content in the house and the weight of the finishing pigs in the back section.Conclusion:The infrastructure of the pig house with the horizontal negative pressure ventilation of the trench is more complete,and the breeding density is 1.5 to 1.7 times higher than that of the traditional pig house.The individual production level of pigs is lower than that of traditional pig houses raised by longitudinal negative pressure ventilation.However,the overall economic benefits of the pig house under the lateral negative pressure ventilation mode of the trench are higher.The air quality in the pig house of the pig house is better than that of the traditional pig house with the longitudinal ventilation mode.