اثر سطوح مختلف خاك دياتومه بر فرآسنجه‌هاي ‌تخميري و قابليت هضم جيره غذايي آلوده با آفلاتوكسينB1 با استفاده از ميكرو ارگانيسم‌هاي جداشده از شكمبه در شرايط برون تني

Effect of diatoms on the fermentation parameters and digestibility of contaminated diet with aflatoxin B1 by microorganisms isolated from rumen in vitro condition

اﯾﻦ آزﻣﺎﯾﺶ ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﯽ اﻓﺰودﻧﯽ ﺧﺎك دﯾﺎﺗﻮﻣﻪ ﺑﺮ اﺛﺮات ﻣﻨﻔﯽ آﻓﻼﺗﻮﮐﺴﯿﻦ در ﺗﻮﻟﯿﺪ ﮔﺎز، ﻗﺎﺑﻠﯿﺖ ﻫﻀﻢ ﻣﺎده ﺧﺸﮏ و ﻣﺎده آﻟﯽ ﺟﯿﺮه ﻏﺬاﯾﯽ ﮔﻮﺳﻔﻨﺪ در ﺷﺮاﯾﻂ آزﻣﺎﯾﺸﮕﺎﻫﯽ اﻧﺠﺎم ﺷﺪ. آزﻣﺎﯾﺶ در ﻗﺎﻟﺐ، ﻃﺮح ﮐﺎﻣﻼ ﺗﺼﺎدﻓﯽ ﺑﺎ 6 ﮔﺮوه آزﻣﺎﯾﺸﯽ و 4 ﺗﮑﺮار در ﻫﺮ ﮔﺮوه در ﺷﺮاﯾﻂ آزﻣﺎﯾﺸﮕﺎﻫﯽ اﻧﺠﺎم ﮔﺮﻓﺖ. ﮔﺮوهﻫﺎي آزﻣﺎﯾﺸﯽ ﺷﺎﻣﻞ: 1-ﺟﯿﺮه ﭘﺎﯾﻪ )ﺷﺎﻫﺪ ﺑﺪون ﻣﺘﺎﻧﻮل(، 2-ﺷﺎﻫﺪ ﺑﺎ ﻣﺘﺎﻧﻮل، 3- ﺷﺎﻫﺪ ﺑﺎ ﻣﺘﺎﻧﻮل + آﻓﻼﺗﻮﮐﺴﯿﻦ ﺑﻪ ﻣﯿﺰان 800ﻧﺎﻧﻮﮔﺮم در ﻣﯿﻠﯽﻟﯿﺘﺮ ﻣﺎﯾﻊ ﺷﮑﻤﺒﻪ )ﺟﯿﺮه آﻟﻮده ﺑﺎ آﻓﻼﺗﻮﮐﺴﯿﻦ(، 5 ،4 و 6- ﺟﯿﺮه آﻟﻮده ﺑﺎ آﻓﻼﺗﻮﮐﺴﯿﻦ + ﺳﻄﻮح 75 ،7 و150 ﻣﯿﻠﯽﮔﺮم دﯾﺎﺗﻮﻣﻪ ﺑﻮدﻧﺪ. از ﺷﯿﺸﻪﻫﺎي ﺑﺎ ﺣﺠﻢ 100 ﻣﯿﻠﯽﻟﯿﺘﺮ ﺑﻪ روش ﮐﺸﺖ ﺛﺎﺑﺖ ﺑﺮاي اﻧﺪازهﮔﯿﺮي ﻣﯿﺰان ﺗﻮﻟﯿﺪ ﮔﺎز و ﻗﺎﺑﻠﯿﺖ ﻫﻀﻢ اﺳﺘﻔﺎده ﺷﺪ. ﻫﺮ ﯾﮏ از ﺷﯿﺸﻪﻫﺎ ﺑﺎ ﮔﺎز دي اﮐﺴﯿﺪ ﮐﺮﺑﻦ ﭘﺮ و ﺳﭙﺲ ﺑﺎ درﭘﻮش ﻻﺳﺘﯿﮑﯽ ﭘﻠﻤﭗ و در ﺣﻤﺎم آﺑﯽ در دﻣﺎي 39 درﺟﻪ ﺳﺎﻧﺘﯿﮕﺮاد اﻧﮑﻮﺑﺎﺳﯿﻮن ﺷﺪ. ﮐﻤﺘﺮﯾﻦ ﻣﻘﺪار ﺗﺠﺰﯾﻪﭘﺬﯾﺮي ﻣﺎده ﺧﺸﮏ و ﻣﺎده آﻟﯽ و ﺑﯿﺸﻨﺮﯾﻦ ﻏﻠﻈﺖ آﻣﻮﻧﯿﺎك ﻣﺮﺑﻮط ﺑﻪ ﮔﺮوه داراي آﻓﻼﺗﻮﮐﺴﯿﻦ ﺑﻮد )0/05

The present study investigated the effect of different levels of diatoms on the in vitro fermentation parameters, dry matter and organic matter digestibility of contaminated diet with aflatoxin B1. This experiment was conducted in a completely randomized design with 5 treatments and 4 replicate per treatment. The treatments were: 1.Control, 2.Control with methanol 3. Contaminated diet with methanol solution containing aflatoxin B1 at 800 ng/ml, 4, 5 and 6. Contaminated diet treated with diatoms at 7, 75 and 150 mg/200mg, respectively. Glass bottles with a volume of 100 ml was used in a constant culture to measure gas production and digestibility. All bottles were purged with anaerobic CO2, sealed with rubber stoppers and incubated in a water bath for 96 h at 39 °C. Culture parameters were measured at different time of incubation. The results showed that the lowest organic and dry matter digestibility value and highest ammonia concentration were related to treatment containing aflatoxin B1 (p<0.05). Aflatoxin caused reduction of gas production parameters, metabolisable energy and VFA compared to control groups. Addition of diatoms at medium and low level (7 and 75 mg/200mg) improved digestibility of dry matter and organic matter compared to aflatoxin group (p<0.05). Cultures containing low level of diatoms also was improved partitioning factor, microbial mass production and efficiency of microbial mass (p <0.05). In conclusion diatoms as feed additive showed promising potential in vitro to improve detrimental effect of aflatoxin on rumen function, therefore more research is guaranteed to investigate their mode of action in the ruminal microbial ecosystem.