Production Performance Measurement And Analysis Of PIC Supporting Pigs

PIC supporting pigs are five-member hybrid supporting lines established through the cultivation of specialized paternal and matrilineal lines.Commercial pigs have excellent production performance and can effectively improve production and economic benefits.Therefore,the number of PIC supporting pigs in China has increased year by year in recent years.However,at present,the lack of production information,unsystematic growth performance measurement and insufficient data accumulation of PIC supporting pigs seriously restrict the continuous breeding and systematic evaluation of production performance of PIC supporting pigs.This paper systematically determines the reproductive performance,growth and development performance and carcass performance of PIC supporting pigs,and compares and analyzes them with the properties of Duroc×(Landrace×Yorkshire)hybrid pigs.The purpose is to provide basic data for the continuous breeding of PIC supporting pigs on the basis of systematicall evaluating the production performance of PIC supporting pigs.In this experiment,the reproduction,growth and development and carcass properties of PIC supporting pigs were measured by on-site measurement.Among them,the number of piglets measured by PIC parental sows was 3,981,the number of PIC piglets was 2,997,the number of piglets tested by PIC parental boars was 8,and 20 PIC piglets(half male and female,of which the boar was castrated boar)were used to determine growth and development performance,and Logistic and Gompertz were used.The two models of fit the growth curve,from which four commercial pigs with normal growth and development were selected for slaughter to determine their carcass properties.On this basis,the production performance of PIC supporting pigs is systematically compared with that of Duroc×(Landrace×Yorkshire)hybrid pigs reported in the literature.The main results are as follows:(1)The delivery rates of PIC parental sows and Landrace-Yorkshire hybrid sows are66.48±16.92%and 76.41±9.65%respectively,the difference between the two is significant(P<0.05);The fetal rate of PIC parental sows is 85.38±9.27%,which is significantly higher than that of Landrace-Yorkshire hybrid sows(83.85±6.41%)(P<0.05);The average number of piglets born in PIC parental sows’primiparity and pluriparity sows is 13.03±2.08 and13.08±2.34 respectively,with no significant difference(P>0.05);The number of piglets born in PIC parental sows is 13.05±2.29,which is significantly higher than that of Landrace-Yorkshire hybrid sows(11.15±0.23)(P<0.05);and The number of live piglets born in PIC parental sows and Landrace-Yorkshire hybrid sows is 10.55±4.07 and 10.40±0.31 respectively,and there is no significant difference between the two(P>0.05).The average birth weight of PIC commodity piglets and Duroc×(Landrace×Yorkshire)hybrid commodity piglets is1.00±0.10 kg and 1.46±0.12 kg respectively,with a significant difference between the two(P<0.05).(2)The semen volume,sperm survival rate and sperm density of PIC parental boars are259.38±82.53 m L,90.13±1.73%and 3.66±802 million/m L respectively.The semen volume,sperm activity rate and sperm density of Duroc boars are 169.42±1.49 m L,80.88±8.72%and2.17±83 million/m L,respectively.The above indicators of PIC parental boars are significantly higher than Duroc boars(P<0.05).(3)The weight of PIC commercial castrated boar from 30 days to 150 days is significantly higher than that of sows(P<0.01).From 90 days to 150 days old,the castrated boar is significantly higher than that of sows(P<0.01).The body height of PIC commodity castration boar and sow varies significantly at the age of 90 and 120(P<0.05),the legs and hip circumference of PIC commodity castration boars and sows are very different from 90 days to150 days old(P<0.01),and their chest circumference is very different from 30 days to 150days old(P<0.01).There is no significant difference between PIC commodity castration boar and sow and other growth and development indicators.The Logistic model and Gompertz model were used to fit the growth curve of PIC commodity castration boar and sow,and found that the fit of the Gompertz model to PIC commodity castration boar(R~2=0.99281)and sows(R~2=0.99083)is better than the Logistic model’s fitting degree for PIC commodity castration boar(R~2=0.99179)and sow(R~2=0.99039).Therefore,priority is given to the Gompertz model for growth curve fitting.Under this model,the growth inflection point is calculated.The age of the growth inflection point of PIC commodity castration boar is 131.49 d,the weight is99.62 kg,the growth inflection point of sows is 98.15 d and the weight is 55.88 kg.Compared with actual production,it is found that the actual growth rate of sows is slightly faster than that fitted by the Gompertz model,while the actual growth rate of castrated boar is not much different from the growth curve fitted by the model.The daily consumption of PIC commercial pigs(1.78±0.15 kg)is significantly lower than that of Duroc×(Landrace×Yorkshire)hybrid commodity piglets(1.93±0.21 kg)(P<0.05);the average daily weight gain of PIC commercial pigs(862±77 g)is significantly higher than that of Duroc×(Landrace×Yorkshire)hybrid commodity piglets(840±106 g)(P<0.05);however,the meat ratio of PIC commercial pigs(2.78:1)is significantly higher than that of Duroc×(Landrace×Yorkshire)hybrid commodity pigs(2.53:1)(P<0.05).(4)The slaughter rate(82.31±4.40%)and eye muscle area(49.84±6.78 cm~2)of PIC commercial pigs are significantly higher than Duroc×(Landrace×Yorkshire)hybrid commodity pigs(P<0.05);PIC commercial pigs’skin thickness(0.25±0.02 cm)is significantly lower than Duroc×(Landrace×Yorkshire)hybrid commodity pigs(P<0.05);there is no significant difference in carcass oblique length,carcass length and hind leg ratio(P>0.05).The proportion of lean meat,bones and skin in carcass weight of PIC commercial pigs is72.41±3.11%,8.93±1.00%and 5.96±0.34%respectively,compared with 69.58±1.86%,10.36±0.54%and 7.22±0.39%of lean meat,bones and skin of Duroc×(Landrace×Yorkshire)hybrid commodity pigs(P<0.05);there is no significant difference between the fat traits of PIC commercial pigs and Duroc×(Landrace×Yorkshire)hybrid commodity pigs(P>0.05),which is 12.70±2.14%and 12.83±1.35%respectively.In this experiment,the reproductive performance of PIC parental sows was significantly better than that of Landrace-Yorkshire hybrid sows in terms of fetal rate and nest yields;the semen volume,sperm density and sperm activity rate of PIC parental boars were better than that of Duroc boars;the daily weight gain and meat ratio of PIC commercial pigs were significantly higher than that of Duroc×(Landrace×Yorkshire)hybrid commodity pigs;the slaughter rate,lean meat rate and eye muscle area of PIC commercial pigs were significantly higher than Duroc×(Landrace×Yorkshire)hybrid commodity pigs.