Design And Determination Of Numerically Controlled Pen And Its Growth Performance Influence On Piglets

Because of the higher temperature requirements of piglets than those of sows,in modern pig production,artificial heating sources are used for piglets before age of 28 days to ensure normal growth and development.Heating pads and infrared lamps are common equipment in combination with piglet boxes.However,the constant power heating can not effectively meet the temperature requirements of piglets,and the heating box also worsen the air quality.Through systematic evaluation and the construction of the optimal temperature model of piglets,this study aims to design a numerical control box which can efficiently provide a suitable environment for piglets,meet animal welfare requirements,and then improve piglets' performance.Experiment 1: With DS18B20 and MQ-135 as the main sensor,the numerical control box is equipped with a single-chip system to complete the electronic communication design of temperature control and harmful gas control modules.Taking Watt-hour Meter,infrared temperature sensor,and the display module of the box as measurement tool,the heat leakage coefficient,heat transfer coefficient,inside temperature distribution,exhaust performance,and energy consumption are measured of the numerically controlled insulation box.The results show that: when the external temperature is from 5 ? to 20 ?,the temperature in the box can meet the growth needs of piglets;the heat leakage coefficient of the box is 17.83 W/K,and the heat transfer coefficient is 12.4 W/(m·K);the numerical control box with low-air-speed negative-pressure ventilation can effectively reduce the harmful gases;when the Outside temperature is 20 ?,the numerical control box saves 36% of energy,improves 33% insulation performance,and keeps the temperature more stable.Experiment 2: the surface temperature scores valued by infrared temperature sensors and lying posture score obtained by video devices was used to determine the optimal temperature for piglets of different ages.Build the optimal temperature curve for different newborn heavy piglets.The results showed that: the optimal temperature of high-birthweight piglets decreased rapidly and stabilized after two weeks of age(y =-0.0003x4 + 0.0157x3-0.2736x2 + 0.806 x + 34.691,R2 = 0.987,P<0.01);The optimal temperature of low-birth-weight piglets continued to decrease slowly untilweaning remained above 26 ?(y =-0.387 x + 35.505,R2 = 0.9683,P <0.01).24 litter piglets with similar health status and similar birth period were selected as experimental animals.After the piglets were born,the weak larvae were removed,6 litter piglets were placed in a numerical control box(R group),and 6 litter piglets were placed Reared in a numerically controlled box and added toys(RT group);6 litters were placed in a traditional box(T group);6 litters were placed in a traditional box and added toys(TT group).Results showed that: piglets in the numerical control box preformed significantly more playing at age of 7,14,and 23 days(P < 0.05);and piglets with toys preformed more playing at age of 7 and 14 days(P < 0.05).There is no interaction between toys and heating box on playing.Piglets in the numerical control box preformed significantly more penmates nosing at age of7,14,and 23 days(P < 0.05);and piglets with toys preformed more pen mates nosing at age of 7days(P < 0.05).There is no interaction between toys and heating box on pen mates nosing.Piglets in the numerical control box preformed significantly more exploring at age of 7 days(P < 0.05);and piglets with toys preformed more exploring at age of 7 days(P < 0.05).There is no interaction between toys and heating box on exploring.There was no significantly effect of heating box or toys on lying and lateral lying.At age of7 days,piglets in the numerical control box spent more time out of the box,while toy lead them spent less time out of the box(P < 0.05).Compared to piglets in traditional box,the daily weight gain of piglets in the numerical control box was higher(P < 0.1),and they were less getting diarrhea(P <0.1).And,at age of 7days,there were significantly more body damage in piglets in the numerical control box(P<0.01).Toys had no effect on healthy.In conclusion,application of y =-0.0003x4 + 0.0157x3-0.2736x2 + 0.806 x + 34.691 and y=-0.387 x + 35.505 temperature model regulated incubators for high birth weight piglets and low birth weight piglets,can better meet piglet need and reduce energy consumption.