Screening Of Suitable Duck Breeds And Its Effect On Rice-duck Farming System

Rice-duck farming,as a kind of ecological recycling agricultural method,has been promoted and applied in production for many years,and achieved certain economic and social benefits.At present,the production of rice-duck farming is mainly based on local ducks in the region However,due to the differences in the growth performance and field labor ability between different ducks,the effects of rice-duck farming are not uniform-Based on this,this study took five kinds of duck breeds with different characteristics,such as small-sized of Jinding duck,Yiyong duck(mallard?×Jinding duck?)and Suyou duck,medium-sized of Baigai duck and Gaoyou duck as research objects by comparing the difference of different duck breeds in water resistance,survival rate,recovery rate and behavior in rice fields,and analyzing the differences in growth performance and muscle quality of different duck breeds in rice-duck farming to select suitable duck breeds And then verify the results of selected duck breeds on weeds,soil,rice yield and rice quality.This study aimed to provide theoretical and practical basis for the optimization and application of rice-duck co-production technology.The main results of this study were as follows:1.To compare the water resistance,survival rate and work time of different duck breeds,water resistance test was carried out at 0 days of age,the results showed that,the water resistance time of Suyou ducks,Jinding ducks and Yiyong ducks reached more than 30 h,which were higher than Baigai ducks and Gaoyou ducks.The survival rate of Jinding ducks was the highest in(96.93%),followed by Yiyong ducks(94.17%)and Suyou ducks(92.24%)during the brooding period.Besides,the recapture rate was the highest in Yiyong ducks(100.00%),and the lowest in Gaoyou ducks(66.67%).In addition,the behaviors of ducks in rice fields had also been observed.The ducklings of 18 day old were placed with the density of 15 ducklings/mu in the experimental plot,and its behaviors were observed continuously for 5 days through the video monitoring system.The results revealed that the daily activity times of Yiyong ducks,Jinding ducks and Suyou ducks were 324.50 min,315.75 min and 314.50 min,respectively,which were significantly longer than that of Gaoyou ducks and Baigai ducks(P<0.01)2.To analyze the difference of growth and muscle quality among the different duck breeds,the slaughter performance and muscle quality of 90-day-old ducks were measured after standardized feeding.The results showed that the body weights of small-sized ducks,including Jinding ducks,Yiyong ducks and Suyou ducks,were more than 1.3 kg,while that of the medium-sized duck,such as Gaoyou ducks and Baigai ducks were from 2.1 to 2.2 kg.The body weights of these five breeds all reached the standard weight,which indicated that the duck breeds showed good growth and development in the rice-duck farming mode.The slaughter rate of each breeds was over 80%and the total net sputum rate was over 60%.The meat of Jinding ducks and Suyou ducks had the higher protein content and the lower moisture content.The pH value was the highest in meat of Yiyong ducks,which was significantly higher than that of Jinding ducks(P<0.05).The fat and collagen content were the highest in Gaoyou ducks.3.To screen duck breeds suitable for rice-duck farming,the important indicators related to the performance of rice-field ducks,including the water resistance time,the brooding survival rate,work time in the field,the body weight and the recapture rate were selected.The principal components analysis was carried out,and two principal components were extracted,and the cumulative variance contribution rate was 81%.A comprehensive performance evaluation model was established in the rice-duck farming:Y=0.307zxi+0.356zx2+0.296zx3-0.483zx4+0.233zx5.The Yiyong duck,Jinding duck and Suyou duck were determined to be suitable for rice-duck farming after the comprehensive scores were sorted.4.To further verify the effect of selected duck breeds on paddy ecology and rice growth,the Jinding ducks were selected and carried out in the rice-duck farming according to standard techniques and requirements.It was found that the weeds was 3.26 plants/m2 in the rice-duck farming area.The control rate of farmland weeds was 99.5%comparing with the control areas.The alkaline nitrogen in soil increased by 13.58 mg/kg in the rice-duck farming area.Although the content of available phosphorus,available potassium and organic matter decreased,descent range was significantly less than that of the control areas.The number of kernels,seed setting rate and 1000-grain weight of rice-duck farming increased by 10.26%,2.15%and 2.72%,respectively,which all significant higher than those of the control area(P<0.05).The rice yield increased by 75.24 kg/mu compared with the control areas.The total economic benefits of rice-duck farming were higher than control group 25162 yuan/hm2.The mode of Rice-duck farming contribute to promotion of duck growth performance,muscle quality and rice quality in a certain degree.Taken together,firstly,the Jinding ducks and the Yiyong ducks,as small-sized duck,had longer activity time,better water resistance and higher survival rate in the field,and the standardbody weight reached aslo standard weight when the ducks were recaptured.These two breeds could fully exert the potential in the rice-duck farming.Secondly,Suyou ducks have the strong water resistance,good activity,outstanding meat production performance and muscle quality.Therefore,Suyou ducks was also optional in mode of rice-duck farming if duck carcass required more meat.Thirdly,mode of the rice-duck farming could increased economic efficiency,improve soil feracity and rice yield,and inhibit weed growth to some extent.