The Effect Of Appropriate Proportion Between Sid Lysine And Metabolic Energy On Growth And Development During The Phrase Of Guangzhong Black Nursery And Growth Fattening Pigs

The Guanzhong black pigs were cultivated varieties in Shanxi province. It was the firstbatch of geographical marked products of agriculture ministry with many characteristics suchas strong disease resistance, high fecundity and good meat quality, etc. Since cultivated,nutritional requirement of Guanzhong black pigs have changed gradually. Lysine is the firstrestrictive amino acid in corn-soybean diets of pigs and its content directly affected growthperformance and slaughter characteristics of piglets and growing-finishing pigs.In this experiment, we got appropriate proportion of SID lysine and metabolic energy indifferent growth stage of Guanzhong pig by the research on the proportion of SID lysine andmetabolic energy between piglets and growing-finishing pigs. The study provided atheoretical basis for production and breeding of the Guanzhong black pigs.The results wasshown below.1. Research on the proportion of SID lysine and metabolic energy in6~20kg Guanzhongblack pigletsWe chose piglets of early conservation (6kg) and late conservation (20kg) for60,respectively. The addition of SID lysine was2.29g/Mcal,2.57g/Mcal,2.88g/Mcal,3.16g/Mcal and3.45g/Mcal, respectively, and metabolic energy remained3.22Mcal/kg.Results were shown below.(1) In the6~12kg phase: Compared with groups of2.29g/Mcal, the average daily gainof groups of3.45g/Mcal and2.57g/Mcal increased significantly （p<0.05）; When SID lysinewas3.45g/Mcal and3.16g/Mcal, total plasma proteins had significantly higher levels thanother groups（p<0.05）; When SID lysine was3.45g/Mcal, plasma protein nitrogen and crudeprotein apparent digestibility remained much higher than other three groups except that thegroup of3.16g/Mcal（p<0.05）; Different addition of SID lysine had little effect on averagedaily feed intake, feed conversion rate, plasma albumin, apparent digestibility of dry matterand apparent digestibility of energy, apparent digestibility of calcium and phosphorus.(2) In the13~20kg phase: When SID lysine was3.16g/Mcal and2.57g/Mcal,,average daily gain higher than other treatment groups （p<0.05）; When SID lysine remained3.16g/Mcal, feed conversion rate was significant lower compared to other treatment groups（p<0.05）; When SID lysine was2.57g/Mcal, crude protein apparent digestibility remainedmuch higher than other treatment groups（p<0.05）; Different addition of SID lysine hadlittle effect on other determined indexes in this stage. 2. Research on the proportion of SID lysine and metabolic energy in20~35kgGuanzhong growing pigs.20kg Guanzhong growing pigs were for40. The addition of SID lysine was1.88g/Mcal,2.10g/Mcal,2.32g/Mcal,2.53g/Mcal and2.75g/Mcal, respectively and metabolic energyremained3.24Mcal/kg. Results were as follows:when SID lysine was2.75g/Mcal, average daily gain and plasma urea nitrogen weresignificantly higher than other test groups（p<0.05）; Conversely, feed conversion ratedecreased significantly compared to other test groups（p<0.05）; Different addition of SIDlysine had little effect on other determined indexes in this stage.3. Research on the proportion of SID lysine and metabolic energy in50~70kg and70~90kg Guanzhong black pigsAbout50kg Guanzhong black pigs for18were chosen and a consecutive test was forgrowth stage divided into two stages:50~70kg and70~90kg. When the diet metabolizableenergy remained3.07, SID lysine was1.66g/Mcal,1.86g/Mcal and2.05g/Mcal. When the dietmetabolizable energy remained3.04Mcal/kg, SID lysine was1.58g/Mcal,1.74g/Mcal and1.91g/Mcal. Results were as follows:(1) In the50~70kg phase, when SID lysine was2.05g/Mcal, feed conversion ratio waslower dramatically than other test groups（p<0.05）. In the basic diet, different addition of SIDlysine had little effect on average daily gain and average daily feed intake.(2) In the70~90kg phase, when SID lysine was1.91g/Mcal, average daily gain,marbling and bone percentage increased significantly compared to other test groups（p<0.05）.On the contrary, feed conversion rate, slaughter rate, ribeye area and meat color decreasedsignificantly compared to other test groups（p<0.05）; When SID lysine was1.58g/Mcal,carcass weight and thickness of backfat were significantly higher than other test groups（p<0.05）; Different addition of SID lysine had little effect on other determined indexes inthis stage.We obtained the following conclusion by integrating production and economic benefits:The appropriate proportion of SID lysine and metabolic energy for different growth stageof Guanzhong black pig were3.45g/Mcal (6~12kg),2.57g/Mcal (13~20kg),2.75g/Mcal(20~30kg),2.05g/Mcal (50~70kg) and1.91g/Mcal(70~90kg), respectively.