Effects Of Shading,Dietary Energy And Protein Levels On Production Performance Of Northeast White Geese In Late Laying Period

Sunshade net as a simple measure to improve the growing environment and animal welfare,it has a good application prospect.In addition,the nutritional intake of poultry during egg production plays an important role in maintaining its production performance,while high temperature will significantly reduce its feed intake and feed utilization rate,which may lead to insufficient nutritional intake of livestock and poultry body.The experiment were used the Northeast White geese in late laying period as test animal,and investigated by measuring its production performance,egg quality and hormone levels in serum,to providing a practical reference for extending laying period and improving production performance.The experiment consisted of 2×2 factorial design with two environment（no shading:NS and have shading:HS）and two levels of dietary energy and protein（diet 1:10.83MJ/kg ME,14.01%CP and diet 2:11.33MJ/kg ME,14.65%CP）.The study was used to select 1608 Northeast White geesewith similar laying rate 365 days old,divided into 6 groups,with 6 replicates in each group and 67 geese in each replicate（55 females and 12 males）.And the experimental period lasted for 63d.Determined the egg production,laying rate,average daily feed intake（ADFI）,average daily egg weight（ADEW）,feed:egg ratio and fertilization rate.At 0（Pre-trial day 1 d）,21,42 and 63 days of experiment,6 eggs were selected from each repeated to detect egg quality.Simultaneously,2 geese were selected from each repeated for superficial venipuncture in the brachial vein blood collection,and detected reproductive hormone in serum（Female:gonadotropin-releasing hormone（Gn RH）,stimulating hormone（FSH）,luteinizing hormone（LH）,prolactin（PRL）,estradiol（E₂）,progesterone（P₄）,melatonin（MT）,T₃,T₄;Male:Gn RH,LH,testosterone（T）,MT,T₃,T₄）.The results are as follows:（1）Compared with NS group,shading significantly increased egg production,laying rate（P<0.01）,and significantly reduced feed:egg ratio（P<0.01）;Compared with diet 1,diet 2significantly reduced egg production,laying rate,and feed/egg ratio（P<0.05）,There were significant interactions between shading and dietary in ADFI and ADEW（P<0.01）,it shown that under the condition of diet 1 and 2,the shading significantly increased ADFI and ADEW（P<0.05）,.（2）Compared with the NS group,shading significantly reduced early-stage test（21 d）,late test（63 d）of egg shape index（P<0.05）and late test of protein height and Haugh unit;Compared with the diet 1,diet 2 significantly improved the early-stage test,medium-test of yolk color（P<0.01）and late test of protein height.There were significant interactions between shading and dietary in protein height,Haugh unit（medium-test）and eggshell thickness（late test）（P<0.05）,it shown that under the condition of diet 1,the shading significantly reduced the mid-test protein height and Haugh unit（P<0.05）,and significantly increased the eggshell thickness at the later stage of the test.（3）Compared with the NS group,shading significantly reduced early-stage test,medium-test,late-test of MT levels（female）（P<0.05）,and significantly reduced T₃（male）（P<0.05）;Compared with the diet 1,diet 2 significantly improved Gn RH（female in early-stage test and late-test）,MT levels（male and female）and T₄（female）were significantly improved in the early-stage test and medium-test（P<0.05）.There were significant interactions between shading and dietary in Gn RH（male）,FSH,PRL,T₃（male）and T₄（male）levels in all period of test（P<0.05）,it shown that under the condition of diet 1,the shading significantly reduced the hormone levels of Gn RH（male）,FSH,PRL,T3（male）and T4（male）（P<0.05）.In summary,based on the analysis of the above indicators,as for the sports field without shade,shading could improve the production performance of Northeast White geese in late laying period.Compared with diet 2（11.33 MJ/kg ME,14.65%CP）,diet 1（10.83 MJ/kg ME,14.01%CP）could improve the laying performance of Northeast White geese.