ﺑﺮﺧﯽ ﻋﻮاﻣﻞ ﺧﻄﺮﺳﺎز ﺑﺮ ﺗﻮﻟﯿﺪ ﻣﺎﻫﯿﺎن ﻗﺰل آﻻي رﻧﮕﯿﻦﮐﻤﺎن ﺑﺎ ﺗﺄﮐﯿﺪ ﺑﺮ ﺷﺎﺧﺺﻫﺎي ﻣﯿﮑﺮوﺑﯽ و ﻓﻠﺰات ﺳﻨﮕﯿﻦ آب ﻣﺰارع ﺣﺎﺷﯿﻪ رودﺧﺎﻧﻪ ﻫﺮاز

Evaluation of some risk factors on the rainbow trout production with emphasis on water microbial indices and heavy metals of farms along the Haraz River

رودﺧﺎﻧﻪ ﻫﺮاز ﻧﻘﺶ ﻣﻬﻤﯽ در ﺗﻮﺳﻌﻪ آﺑﺰيﭘﺮوري و ﺗﻮﻟﯿﺪ ﻗﺰل آﻻي رﻧﮕﯿﻦﮐﻤﺎن در ﻣﺎزﻧﺪران دارد. ﻫﺪف اﯾﻦ ﺑﺮرﺳﯽ ارزﯾﺎﺑﯽ ﺷﺎﺧﺺﻫﺎي ﻣﯿﮑﺮوﺑﯽ و ﻓﻠﺰات ﺳﻨﮕﯿﻦ آب و ﻧﯿﺰ ﺷﻨﺎﺳﺎﯾﯽ ﻋﻮاﻣﻞ ﺑﺎﮐﺘﺮﯾﺎﯾﯽ ﺑﯿﻤﺎري زا راﯾﺞ و ﻗﺪرت ﻣﻘﺎوﻣﺖ آﻧﻬﺎ در ﺑﺮاﺑﺮ آﻧﺘﯽ ﺑﯿﻮﺗﯿﮏﻫﺎي ﻣﺼﺮﻓﯽ ﺑﻪ ﻋﻨﻮان ﻋﻮاﻣﻞ ﻣﻮﺛﺮ ﺑﺮ ﺗﻮﻟﯿﺪ ﻣﺎﻫﯿﺎن ﺑﻮده اﺳﺖ. اﯾﻦ ﺗﺤﻘﯿﻖ ﻃﯽ ﭼﻬﺎر ﻓﺼﻞ )ﺗﺎﺑﺴﺘﺎن، ﭘﺎﯾﯿﺰ و زﻣﺴﺘﺎن 1396 و ﺑﻬﺎر 1397( در 6 ﻣﺰرﻋﻪ ﻣﺠﺎور رودﺧﺎﻧﻪ ﻫﺮاز اﻧﺠﺎم ﮔﺮدﯾﺪ. ﺑﺮ اﺳﺎس ﻧﺘﺎﯾﺞ ﻣﯿﺰان ﺟﯿﻮه آب ورودي ﻣﺰارع ﻣﻮرد ﺑﺮرﺳﯽ در ﺗﻤﺎم ﻓﺼﻮل از ﺣﺪاﻗﻞ 3 ﺑﺮاﺑﺮ ﺣﺪاﻗﻞ ﺣﺪ ﻣﺠﺎز )1 ﻣﯿﮑﺮوﮔﺮم ﺑﺮ ﻟﯿﺘﺮ( ﺗﺎ ﺣﺪاﮐﺜﺮ 6 ﺑﺮاﺑﺮ ﺣﺪاﮐﺜﺮ ﺣﺪ ﻣﺠﺎز )2 ﻣﯿﮑﺮوﮔﺮم ﺑﺮ ﻟﯿﺘﺮ( ﺑﻮد وﻟﯽ ﻣﯿﺰان ارﺳﻨﯿﮏ، ﺳﺮب و ﮐﺎدﻣﯿﻮم در ﺗﻤﺎم ﻣﺮاﺣﻞ ﻧﻤﻮﻧﻪ ﺑﺮداري در ﺣﺪ اﺳﺘﺎﻧﺪارد ﺑﻮد. ﻣﻬﻤﺘﺮﯾﻦ ﻋﻼﯾﻢ ﺑﺎﻟﯿﻨﯽ ﻣﺸﺎﻫﺪه ﺷﺪه در ﻣﺎﻫﯿﺎن، ﭘﻮﺳﯿﺪﮔﯽ ﺑﺎﻟﻪ، ﺷﻨﺎي ﻧﺎﻣﺘﻌﺎرف، اﻟﺘﻬﺎب و ﭘﺮﺧﻮﻧﯽ ﮐﺒﺪ و ﮐﻠﯿﻪ ﺑﻮد. از ﻣﺠﻤﻮع 420 ﻋﺪد ﻣﺎﻫﯽ واﺟﺪ ﻋﻼﯾﻢ ﺑﺎﻟﯿﻨﯽ 12%/15 و 87/85% ﺑﻪﺗﺮﺗﯿﺐ از ﻧﻈﺮ ﮐﺸﺖ ﺑﺎﮐﺘﺮي ﻣﺜﺒﺖ و ﻣﻨﻔﯽ ﺑﻮدﻧﺪ. ﻋﻮاﻣﻞ ﺑﺎﮐﺘﺮﯾﺎﯾﯽ ﺟﺪاﺳﺎزي ﺷﺪه ﻫﻤﮕﯽ از ﺑﺎﮐﺘﺮيﻫﺎي ﮔﺮمﻣﻨﻔﯽ و ﺑﺮاﺳﺎس درﺻﺪ ﻓﺮاواﻧﯽ ﺷﺎﻣﻞ ﯾﺮﺳﯿﻨﯿﺎ )37/25%(، آﺋﺮوﻣﻮﻧﺎس )33/35%(، ادواردزﯾﻼ )11/76%(، وﯾﺒﺮﯾﻮ )7/84%(، ﭘﺎﺳﺘﻮرﻻ )5/88%( و ﺳﯿﺘﺮوﺑﺎﮐﺘﺮ )3/92%( ﺑﻮدﻧﺪ. ﺑﯿﺸﺘﺮﯾﻦ ﻣﻘﺎوﻣﺖ آﻧﺘﯽﺑﯿﻮﺗﯿﮑﯽ در ﺑﺮاﺑﺮ آﻣﻮﮐﺴﯽﺳﯿﻠﯿﻦ و ﮐﻤﺘﺮﯾﻦ آن ﻣﺮﺑﻮط ﺑﻪ ﺗﺮيﻣﺘﻮﭘﺮﯾﻢ ﺳﻮﻟﻔﺎﻣﺘﻮﮐﺴﺎزول ﺑﻮد. در ارزﯾﺎﺑﯽ ﺷﺎﺧﺺﻫﺎي ﻣﯿﮑﺮوﺑﯽ آب ﺷﺎﻣﻞ ﺷﻤﺎرش ﮐﻠﯽ ﺑﺎﮐﺘﺮي، ﮐﻠﯿﻔﺮم، ﮐﻠﯿﻔﺮم ﻣﺪﻓﻮﻋﯽ و اﺷﺮﯾﺸﯿﺎ ﮐﻮﻟﯽ، ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﺷﺎﺧﺺﻫﺎي ﻣﯿﮑﺮوﺑﯽ آب ﺗﻘﺮﯾﺒﺎً در ﺑﯿﺸﺘﺮ ﻣﺮاﺣﻞ ﻧﻤﻮﻧﻪﺑﺮداري ﺑﯿﺶ از ﺣﺪ ﻣﺠﺎز ﺑﻮد. ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﺘﺎﯾﺞ ﺑﻪﻧﻈﺮ ﻣﯽرﺳﺪ، ﺗﺎﺛﯿﺮ ﻓﻠﺰ ﺳﻨﮕﯿﻦ ﺟﯿﻮه ﺑﺮ ﺳﻼﻣﺖ ﻣﺎﻫﯿﺎن ﺑﺮاﺳﺎس ﻋﻼﯾﻢ ﺑﺎﻟﯿﻨﯽ، اﻓﺰاﯾﺶ ﻣﻘﺎوﻣﺖ ﻋﻮاﻣﻞ ﺑﺎﮐﺘﺮﯾﺎﯾﯽ ﺑﯿﻤﺎري زا در ﺑﺮاﺑﺮ آﻧﺘﯽﺑﯿﻮﺗﯿﮏﻫﺎ و ﻧﯿﺰ ﺑﯿﺶ از ﺣﺪ ﻣﺠﺎز ﺑﻮدن ﺷﺎﺧﺺﻫﺎي ﻣﯿﮑﺮوﺑﯽ آب از ﻋﻮاﻣﻠﯽ ﻫﺴﺘﻨﺪ ﮐﻪ ﺑﻪ ﻃﻮر ﻣﺴﺘﻘﯿﻢ و ﻏﯿﺮ ﻣﺴﺘﻘﯿﻢ ﺗﻮﻟﯿﺪ ﻣﺎﻫﯿﺎن ﻗﺰلآﻻ ﻣﺰارع ﺣﺎﺷﯿﻪ رودﺧﺎﻧﻪ ﻫﺮاز را ﺗﺤﺖ ﺗﺎﺛﯿﺮ ﻗﺮار دادهاﻧﺪ. ﻟﺬا، ﺗﻮﺟﻪ ﺑﻪ اﺳﺘﻔﺎده از روشﻫﺎي ﻣﻨﺎﺳﺐ ﻣﺪﯾﺮﯾﺖ آب در ﺟﻬﺖ ﮐﺎﻫﺶ ﺑﺎر ﻣﯿﮑﺮوﺑﯽ و ﻓﻠﺰ ﺟﯿﻮه در ﮐﻨﺎر اﺳﺘﻔﺎده از ﺗﻐﺬﯾﻪ و ﻣﺪﯾﺮﯾﺖ ﭘﺮورش ﻣﻨﺎﺳﺐ ﺗﺎ ﺣﺪود زﯾﺎدي ﻣﺸﮑﻼت ﺗﻮﻟﯿﺪ را در اﯾﻦ رودﺧﺎﻧﻪ ﺣﻞ ﺧﻮاﻫﺪ ﻧﻤﻮد.

Haraz River has an important role in the development of aquaculture and the production of rainbow trout in Mazandaran province. Since 2015, the production of rainbow trout has been decreased in the farms along the river and almost halved. This study have been investigated the microbial indices and heavy metals in water as well as the identification of common bacterial pathogens and their resistance to antibiotics and used them as effective factors in the fish health and production. This study was conducted during four seasons (summer, autumn and winter 2017 and spring 2018) in 6 rainbow trout farms along the Haraz River. The results showed that the amount of the water mercury in all seasons was from minimum 2 to maximum 12 times the allowable limit but the arsenic level was standard in all sampling times. The most important clinical symptoms were observed in the fish including fin rot, erratic swimming, inflammation and hyperemia of the liver and kidneys. From 420 fish with clinical signs, 12.15% and 87.85% of fish were positive and negative bacterial culture respectively. The all of bacterial isolates were gram-negative and no gram-positive bacteria were isolated. The bacterial agents identified were including, Yersinia (37.25%), Aeromonas (33.35%), Eduardzilla (11.76%), Vibrio (7.84%), Pasteurella (5.88%) and Citrobacter (3.92%). The highest and lowest antibiotic resistances were found against amoxicillin and trimethoprim sulfamethoxazole respectively. In evaluation of the microbial water indices including total bacterial count, coliform count, fecal coliform count and E. coli, the results showed that the all of microbial indices were not allowable level in the most of the sampling time.