تاثیر خوراندن مستقیم میکروارگانسیم بر عملکرد، ph دستگاه گوارش، فراسنجه‌های خونی و جمعیت میکروبی روده باریک مرغ‌های تخم‌گذار تغذیه‌شده با جیره غذایی بر پایه گندم-کنجاله سویا

اثر خوراندن مستقیم میکروارگانیسم بر عملکرد، میکرو فلور روده باریک و کور، فراسنجه های خونی و ph  روده باریک مرغ‌های تخم گذار تغذیه‌شده با جیره حاوی گندم از سن 54 تا 62 هفتگی با استفاده از تعداد 240 قطعه مرغ تخم گذار های-لاین w-36 در قالب طرح کاملا تصادفی بین 40 قفس شامل پنج تیمار، هشت تکرار و شش پرنده در هر تکرار بررسی شد. جیره های آزمایشی شامل الف- جیره شاهد بر پایه ذرت- کنجاله سویا، ب- جیره بر پایه گندم بدون افزودنی میکروبی، ج- جیره بر پایه گندم حاوی cfu/kg 109×1 باسیلوس ولزنسیس (b. velezensis)، د- جیره بر پایه گندم حاوی cfu/kg 105×1 قارچ تریکودرما (trichoderma)، و- جیره بر پایه گندم با باسیلوس ولزنسیس+ تریکودرما (b.velezensis + trichoderma)  بود.  نتایج نشان داد که افزودن باسیلوس ولزنسیس+ تریکودرما به جیره منجر به بهبود ضریب تبدیل خوراک نسبت به تیمار شاهد و تیمار بر پایه گندم و افزایش تولید تخم مرغ و مصرف خوراک روزانه شد (0.05>p). هم‌چنین ph محتویات ژژنوم، ایلئوم و روده کور در تیمارهای حاوی میکروارگانیسم ها کاهش یافت (0.05>p). پرندگان دریافت‌کننده میکروارگانیسم ها سطح پلاسمایی کلسیم، فسفر و لیپوپروتئین با چگالی بالا (hdl) بالاتری را داشتند (0.05>p). افزودن باسیلوس ولزنسیس+ تریکودرما به جیره منجر به کاهش تعداد کلنی اشرشیاکلی و افزایش کلنی لاکتوباسیل ها شد. براساس نتایج مطالعه حاضر، می توان نتیجه گرفت که در مرغ‌های تخم‌گذار، افزودن باسیلوس ولزنسیس+ تریکودرما به جیره غذایی بر پایه گندم باعث بهبود عملکرد تولیدی، کاهش سطح کلسترول و تری گلیسیرید پلاسما و بهبود میکروفلور روده می‌شود.

the effect of direct-fed microbials on performance, ph values of gastrointestinal tract, blood parameters and small intestine microflora of laying hens fed wheat-soybean meal-based diet

introduction: corn and wheat are the main sources of energy in poultry diets worldwide, although due to its availability, wheat can be a good substitute for corn in the diet of broilers and laying hens. however, the inclusion level of wheat is limited often because wheatbased diet contained higher levels ofsoluble non-starch polysaccharidesthe arabinoxylans are the main nsp in wheat that increasing the viscosity of the digesta and reducing nutrient digestibility of direct-fed microbial (dfm) supplements include bacillus velezensis, trichoderma, and saccharomyces cerevisiae, which are used as biological control agents due to their high ability to suppress disease agents and inhibit the proliferation of intestinal pathogens.materials and methods: the total number of 240 hy-line w-36 laying hens were randomly distributed between 40 cages, and the five experimental diets including (a) corn-soybean meal-based control diet, (b) wheat-based diet with no microbial additive, (c) wheat-based diet with 1í109 cfu/kg bacillus velezensis, (d) wheat-based diet with 1í105 cfu/kg trichoderma and (e) wheat-based diet with b. velezensis + trichoderma were assigned to hens with 8 replicate cages per diet and 6 hens per each replicate.results and discussion: the results showed that the addition of b. velezensis + trichoderma to the diet led to an improvement in the feed conversion ratio (fcr),  and increased egg production (ep) and feed intake (fi; p<0.05)., also, the ph of the contents of the jejunum, ileum and caecum was reduced in the treatments containing microorganisms(p<0.05). the dfms enhanced the efficiency of nutrient adsorption and utilization, predominantly ascribable to the production of exogenous enzymes by the test probiotic. prebiotics work as feed for the intestinal microflora and could stimulate the fermentation rate which increased the production of short chain fatty acids and reduced luminal ph. hens fed microbe-added diets had higher plasma levels of calcium (ca), phosphorus (p) and high-density lipoprotein (p<0.05). the addition of b. velezensis + trichoderma to the diet, modulated the ileal and caecal microflora composition by decreasing the numbers of escherichia coli and increasing the numbers of lactobacilli. dietary supplemented by b. velezensis and trichoderma could increase plasma ca and p compared to other treatments, which can be interpreted as probiotics increase the rate of fermentation and reduce intestinal ph, leads to better absorption of ca and p from the intestine. improved intestinal morphology characteristics were observed in hens fed the microbe-added diets (p<0.05). these beneficial effects were directly associated with decrease in total microbes, e. coli and salmonella and enhance lactic acid bacteria of cecal. consistently, addition of b. subtilis manipulated the gut ecosystem toward beneficial bacteria and enhanced the development and health of gastrointestinal tract. the positive effects of dfms on eggshell quality can be attributed to the enhancement of gut health and intestinal tract microflora environment. also, modifying the gut microflora composition by promoting the growth of beneficial microflora (such as lactic acid bacteria) and inhibiting the growth of salmonella, e. coli, and clostridium perfringens is beneficial effects of dfms. the present study confirmed b. velezensis and trichoderma enhanced the colonization of the beneficial bacteria and reduced the colonization of enteric bacteria. maintaining a healthy intestine by probiotics and prebiotics will improve the ability of birds to overcome the disease and enhance their performance. highest count of aerobic bacteria, lactobacilli, anaerobic bacteria, and e. coli were associated with trichoderma reesei.