بررسي تاثير استفاده از اسيدهاي آلي بر اكولوژي ميكروبي روده، پاسخ هاي ايمني و قابليت استفاده از فسفر فيتاتي درمرغان تخم گذار

چكيده انگليسي :

Effect of Supplementary Organic Acids on Gut Microflora Immune Responses and Phytate Phosphorus Utilization in Leghorn Laying Hens Fahimeh Kazempour fahimehkazempour@yahoo com Nov 2 2010 Department of Animal Sciences College of Agriculture Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Dr Rahman Jahanian r jahanian@cc iut ac ir Abstract To investigate the effect of dietary organic acids on immune responses gut microflora and phytate phosphorus utilization in Leghorn laying hens two experiments were conducted with Hy line W 36 layers of 34 weeks old The birds were subjected to a 10 d adaptation period and main trial stage lasted 70 d In the fist trial a total of 210 hens were assigned to 7 dietary treatments with five replicates of six birds each to evaluate the effect of acid type and level on performance and immune responses Dietary treatments were consisted a control group and levels of 0 25 and 0 5 of each of three different acids salt forms of citric butyric or fumaric acids The results showed that dietary organic acid supplementation during first 35 d caused significant P 0 01 increase in egg production Also egg production rate in whole experimental period was affected by acid type by level interaction so that increase in acid level from 0 25 to 0 5 markedly P 0 05 improved egg production only in citrate group Egg mass was also affected P 0 05 by dietary treatments during the first 35 d as well as whole trial period Dietary inclusion of organic acids decreased serum cholesterol and triglycerides and increased serum HDL P 0 05 Antibody titers against Newcastle disease virus at days 7 and 14 post vaccine inoculation had different pattern among dietary treatments and increase in dietary acid level totally decreased antibody titers at 7th post vaccination Experiment 2 was performed with 240 laying hens that randomly allocated to a 2 4 factorial arrangement of treatments with 2 levels of non phytate phosphorus 60 or 100 of NRC recommendations and 4 different basal diets control versus diets containing salt forms of citrate butyrate or fumarate Egg weight was decreased P 0 01 with diets low in phosphorus level during the first 35 d and in the whole trial period Also egg production was markedly P 0 05 different among the acid diets so that only citrate resulted in significant increase in egg production rate Feed conversion ratio was considerably P 0 01 lower in 100 NPP diets than that of 60 NPP diets Dietary inclusion of organic acids P 0 01 and also increase in dietary non phytate phosphorus level P 0 05 resulted in significant decreases in serum cholesterol in mid and whole period respectively In contrast serum HDL concentration was markedly P 0 001 increased by dietary acid supplementation Although Newcastle antibody titer wasn t affected by phosphorus level dietary organic acids improved P 0 01 antibody titers in both 7 and 14 d post inoculation In overall organic acids increased tibia ash P 0 01 and calcium P 0 001 percentages and bone ash was greater P 0 01 in groups with 100 NPP level than in 60 counterparts Interestingly dietary organic acid supplementation caused considerable reduction in ileum E coli P 0 05 and Salmonella P 0 01 and increase in Lactobacillus P 0 01 counts Also feeding the diets contained in organic acids resulted in significant P 0 001 improvements in ileal protein calcium and phosphorus digestibilities In conclusion the present findings indicate that organic acids could increase laying performance probably via modulation of gut microbial populations and improvement in nutrient digestibility and it seems that organic acids can be used as good antibiotics alternatives Keywords Laying hens Organic acids Phytate phosphorus Immune responses Gut microbial ecology Ileal digestibility

كاظم پور، فهيمه

بررسي تاثير استفاده از اسيدهاي آلي بر اكولوژي ميكروبي روده، پاسخ هاي ايمني و قابليت استفاده از فسفر فيتاتي درمرغان تخم گذار

فسفر فيتاتي , پاسخ هاي ايمني , قابليت هضم ايلئومي