不同光照时间对肉鹅生长性能及内毒素的影响

为研究不同光照时间对肉鹅生长性能和血清内毒素含量的影响，试验选取３个组，每组随机不分性别选取３２只４周龄马岗鹅．对照组接受正常光照（１２Ｌ∶１２Ｄ）（Ｌ∶光照ｌｉｇｈｔ，Ｄ：黑暗ｄａｒｋ），短日照组每天９ｈ日照（９Ｌ∶１５Ｄ）；长日照组每天１５ｈ日照（１５Ｌ∶９Ｄ），试验持续８周后，测定体质量增长速度、存活率、料重比、血 清内毒素等指标．结果表明，体质量从第７周开始对照组要显著高于短日照组和长日照组（Ｐ＜０.０５）．鹅生长发育早期（４～８周）对照组的饲料转化率最高，而后期（９～１２周）则是长光照组的饲料转化率最高．对照组和长光照组的存活率都达到８０.０％以上，而短日照组只有６６.７％．在整个试验期间对照组的血清内毒素含量均比其余两组小．试验表明，接受正常光照（１２Ｌ∶１２Ｄ）的鹅群有较好的生长性能，而长光照可提高鹅生长发育后期的饲料转化率．

Effects of different photoperiod on the growthperformance and endotoxin of geese

There were three groups in the experiment，each group was randomly selected 32 Maganggeese to study the effects of different light time on the growth performance of goose and serum endotoxincontent． The control group received normal light ( 12L∶ 12D) ( L: light，D: dark) ，the short-photope-riod group received 9 hours light ( 9L∶ 15D) and the long-photoperiod group received 15 hours light ( 15L∶ 9D) ． After 8 weeks，the growth rate of body mass，survival rate，feed gain ratio and serum endotoxinwere measured． The results showed that body mass in the control group was significantly higher than thosein the short-sunshine and long-sunshine group ( P ＜0. 05) from week 7． It was found that the feed con-version rate was highest in the control group at the early stage ( 4 －8 weeks) ，while that was highest atthe long-sunshine group in the latter stage ( 9 －12 weeks) ． The survival rates of the control group andlong-light group reached more than 80. 0%，while the survival rate of the short-day group had only66. 7%． The mean serum levels of endotoxin in the control group were lower than those of the other twogroups during the whole experiment． Thus，the different light time could affect the growth performanceand serum endotoxin content of Magang goose． In this experiment，geese that received normal light ( 12L∶ 12D) had better growth performance，and long photoperiod could improve the feed gain ratio of geese inlater growth and development stage．