ﻫﻤﺒﺴﺘﮕﯽ ﺑﯿﻦ ﻋﻨﺎﺻﺮﮐﻤﯿﺎب،اﺳﺘﺮس اﮐﺴﯿﺪاﺗﯿﻮ و ﮐﺘﻮز ﺗﺤﺖ ﺑﺎﻟﯿﻨﯽ ﻃﯽ دوره اﻧﺘﻘﺎل درﮔﺎوﻫﺎي ﺷﯿﺮي

در ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ، ﻫﻤﺒﺴﺘﮕﯽ ﺑﯿﻦ ﻋﻨﺎﺻﺮ ﮐﻤﯿﺎب، اﺳﺘﺮس اﮐﺴﯿﺪاﺗﯿﻮ و ﮐﺘﻮز ﺗﺤﺖ ﺑﺎﻟﯿﻨﯽ ﻃﯽ دوره اﻧﺘﻘﺎل در ﮔﺎوﻫـﺎي ﺷـﯿﺮي ﻣـﻮرد ارزﯾـﺎﺑﯽ ﻗـﺮار ﮔﺮﻓﺖ .ﻧﻤﻮﻧﻪ ﻫﺎي ورﯾﺪ وداج و در زﻣﺎن ﻫﺎي ﺳﻪ ﻫﻔﺘﻪ و ﯾﮏ ﻫﻔﺘﻪ ﻗﺒﻞ از زاﯾﺶ و ﯾﮏ ﻫﻔﺘﻪ و ﺳﻪ ﻫﻔﺘﻪ ﺑﻌﺪ از زاﯾﺶ اﺧـﺬ ﮔﺮدﯾـ ﺪ ﺧﻮن از .ﺑـﺎﻻﺗﺮﯾﻦ ﻣﻘﺪار ﻣﺎﻟﻮن دي آﻟﺪﻫﯿﺪ و ﺑﺘﺎﻫﯿﺪروﮐﺴﯽ ﺑﻮﺗﯿﺮات در ﻫﻔﺘﻪ اول ﭘﻌﺪ از زاﯾﺶ ﻣﺸﺎﻫﺪه ﮔﺮدﯾﺪ .ﺑﺮ ﻋﮑﺲ، ﻏﻠﻈﺖ ﺳﺮﻣﯽ ﻣﺲ، روي، آﻟﺒﻮﻣﯿﻦ، اﺳﯿﺪ اورﯾﮏ ﺑﻌﺪ از زاﯾﺶ ﮐﺎﻫﺶ ﯾﺎﻓﺖ .ﭘﺲ از زاﯾﺶ، ﻏﻠﻈﺖ روي ﻫﻤﺒﺴـﺘﮕﯽ ﻣﻨﻔـﯽ ﻣﻌﻨـﯽ داري را ﺑـﺎ ﻣﻘـﺪار ﻣـﺎﻟﻮن دي (TIBC)و ﻇﺮﻓﯿﺖ ﺗﺎم اﺗﺼﺎل ﺑﻪ آﻫﻦ آﻟﺪﻫﯿﺪ ﻧﺸﺎن داد ( .ﯽ ﻣﺜﺒﺖ ﻣﻌﻨﯽ داري ﺑﯿﻦ ﻣﻘﺎدﯾﺮ ﻣﺎﻟﻮن دي آﻟﺪﻫﯿﺪ و ﺑﺘﺎﻫﯿﺪروﮐﺴﯽ ﺑـﻮﺗﯿﺮات ﭘـﺲ از زاﯾـﺶ ﻣﺸـﺎﻫﺪه ﮔﺮدﯾـﺪ p <0.005) ﻫﻤﺒﺴﺘﮕ ( (، در ﺣﺎﻟﯽ ﮐﻪ ﻫﻤﺒﺴﺘﮕﯽ ﺑﯿﻦ روي و ﺑﺘﺎ ﻫﯿﺪروﮐﺴﯽ ﺑﻮﺗﯿﺮات در اﯾﻦ زﻣﺎن ﻣﻨﻔﯽ ﺑﻮدp <0.005) .ﻧﺘﺎﯾﺞ آزﻣﻮن رﮔﺮﺳﯿﻮن ﻟﻮﺟﺴـﺘﯿﮏ ﻧﺸـﺎن p <0.05) داد ﮐﻪ ﮐﺎﻫﺶ ﻏﻠﻈﺖ روي در ﯾﮏ ﻫﻔﺘﻪ ﻗﺒﻞ و ﯾﮏ ﻫﻔﺘﻪ ﺑﻌﺪ از زاﯾﺶ، اﺣﺘﻤﺎل رﺧﺪاد ﮐﺘﻮز ﺗﺤﺖ ﺑﺎﻟﯿﻨﯽ را اﻓﺰاﯾﺶ ﻣﯽ دﻫﺪ .ﺑﻪ ﻋﻼوه اﻓﺰاﯾﺶ ﻏﻠﻈـﺖ ﻣﺎﻟﻮن دي آﻟﺪﻫﯿﺪ در ﻫﻔﺘﻪ اول ﺑﻌﺪ از زاﯾﺶ، ﺧﻄﺮ ﮐﺘﻮز ﺗﺤﺖ ﺑﺎﻟﯿﻨﯽ را اﻓﺰاﯾﺶ ﻣﯽ دﻫﺪ .ﻧﺘﺎﯾﺞ ﺣﺎﺻﻞ از ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ ﻧﺸﻠﻦ ﻣـﯽ دﻫـﺪ ﮐـﻪ ﮔﺎوﻫـﺎي ﺷﯿﺮي داراي ﻣﻘﺎدﯾﺮ ﻧﺎﮐﺎﻓﯽ از ﻋﻨﺎﺻﺮ ﮐﻤﯿﺎب ﻣﺴﺘﻌﺪ ﺑﻪ اﺳﺘﺮس اﮐﺴﯿﺪاﺗﯿﻮ و ﮐﺘﻮز ﺗﺤﺖ ﺑﺎﻟﯿﻨﯽ ﻫﺴﺘﻨﺪ .از ﻃـﺮف دﯾﮕـﺮ ﮔﺎوﻫـﺎي ﺑـﺎ اﻓـﺰاﯾﺶ اﺳـﺘﺮس اﮐﺴﯿﺪاﺗﯿﻮ ﻣﺴﺘﻌﺪ ﺑﻪ ﮐﺘﻮز ﺗﺤﺖ ﺑﺎﻟﯿﻨﯽ ﺧﻮاﻫﻨﺪ ﺑﻮد .

The possible relationships between trace elements, oxidative stress and subclinical ketosis during the transition period were evaluated in dairy cows. Blood samples were obtained by jugular venipuncture at four times of the transition period: 3 weeks and 1 week before and 1 week and 3 weeks after calving. The highest concentrations of malondialdehyde (MDA) and betahydroxybutyrate (BHB) were observed on the week 1 after calving. In contrast, the serum values of copper, zinc, albumin, uric acid and TIBC decreased after calving. After calving, zinc concentration showed a significant negative correlation with MDA concentration (p <0.005). The concentrations of MDA after calving showed a positive correlation with BHB (P <0.005), while zinc showed a negative correlation with BHB at this time (p <0.05). The results of logistic regression test showed that the decreased concentration of zinc in the weeks 1 before and week 1 after calving was associated with the probability of occurrence of subclinical ketosis. Moreover, an increase in MDA concentration at the week 1 after calving was associated with the risk of subclinical ketosis. The results of the present study showed that cattle with insufficient concentrations of trace elements are prone to oxidative stress and cattle with increased oxidative stress may be subclinical Ketosisprone.