High humidity will aggravate the heat or cold, and lead to the growth of microorganisms in piggery, resulting in corrosion of piggery equipment and feed. The humidity of pigsty is too small and the dust increases, which is easy to induce respiratory diseases.
According to the experiment in piggery with the same temperature but different humidity, under the condition of high relative humidity, the weight of experimental piglets decreased, the weight gain rate slowed down and the feed consumption increased. The litter size of pregnant sows and parturient sows growing in wet and dark pigsty is 23. 1% lower than that growing in dry and bright pigsty, and the weaning litter weight of piglets is low 18. 1%. When the relative humidity is 60% ~ 70%, the daily gain of pigs is 675g at 22℃ and 530g at 28℃. When the relative humidity is 90% ~ 95%, the daily gain of pigs is 670g at 22℃ and only 485g at 28℃.
High humidity will also cause condensation on the wall and roof, reducing the thermal insulation performance of the pigsty structure. According to the measurement, the thermal conductivity of humid air is about 10 times that of dry air. The greater the humidity in the pigsty, the worse the thermal insulation performance, and the more heat the pig loses, the pig will feel cold.
affect health
Weaken the body's resistance. Humidity will weaken the body's resistance, leading to the occurrence and spread of parasitic diseases such as piglet paratyphoid, erysipelas, piglet diarrhea and scabies. It is reported that after the rainstorm, when the daily temperature difference is above 10℃ and the relative humidity increases by about 20%, the diarrhea piglets increase by 1 ~ 8 times.
Feed and bedding are moldy. Under the condition of low temperature and high humidity, feed and bedding grass are prone to mildew, thus inducing respiratory diseases, colds and rheumatic diseases.