Canjin uwa a cikin dabbobi masu shayarwa
A cikin Dabbobi masu shayarwa na ruwa, canja wurin uwa shine motsi na gurɓataccen abu daga uwa zuwa 'ya'ya, yawanci na gurɓatar lipophilic yayin da yake cikin mahaifa ko ta hanyar madarar uwa. Wannan ya zama mahimmanci tare da karuwar amfani da gurɓataccen kwayoyin halitta (POPs). POPs Biomagnify saboda yanayin lipophilic kuma sun taru a cikin ƙwayoyin lipid na dabbobi masu shayarwa. Ana amfani da waɗannan lipids azaman makamashi ga uwa yayin ci gaban 'ya'ya, wanda ke saki POPs a cikin ruwa mai zagayawa. Wannan yana haifar da canja wurin masu guba a cikin tayin da ke tasowa a lokacin daukar ciki da kuma cikin madara da dabba mai shayarwa ke samarwa a lokacin shayarwa.
Tarihi da asali
[gyara sashe | gyara masomin]Dabbobi masu shayarwa na ruwa suna fuskantar sunadarai iri-iri a duk rayuwarsu, galibi ta hanyar abincin su. Da zarar sunadarai sun tara a cikin ƙwayoyin jiki na dabbobi masu shayarwa, wani ɓangare na waɗannan sunadarai a cikin dabbobi masu sha suna canja wurin su ga 'ya'yansu yayin daukar ciki da shayarwa.
Matsayin canja wurin uwa-mai na gurɓataccen sinadarai yana shafar sinadarai da kayan jiki na waɗancan mahadi. Lipophilicity, ɗaure furotin, da hanyoyin sufuri masu aiki duk suna tasiri ga shawo kan rarraba irin waɗannan sunadarai a cikin ƙwayoyin uwa.[1] Ana iya canja wurin sunadarai na lipophilic, kamar POPs da yawa, ta hanyar mai na madara, yayin da za'a iya canja wurin abubuwan hydrophilic tare da ruwa na madara. Kwayar tana ba da shingen ga wasu gurɓataccen abu, amma yana da ɗan ga wasu, gami da kwayoyin halitta da wasu ƙarfe masu nauyi kamar gubar, mercury da cadmium, musamman idan aka haɗa shi da kwayoyin kwayoyin halitta.
Hanyoyin Canjin Uwa
[gyara sashe | gyara masomin]Yin shayarwa
[gyara sashe | gyara masomin]Canjin gurɓataccen abu daga uwa zuwa jariri ta hanyar shayarwa mai yiwuwa shine mafi girman canjin gurɓatawa, mafi girma fiye da na canjin ciki.[2] Lokacin da mahaifiyar ta fara shayarwa, ana canza lipids na mai zuwa lipids na madara don ciyar da 'ya'yanta. A lokacin wannan tsari, ana tura kwayoyin da aka adana a cikin man fetur a cikin madara sannan daga baya a tura su ga jariri.
Canjin abubuwa masu guba ta hanyar shayarwa yana motsawa ta hanyar log Kow na abubuwa masu gubobi. Magungunan sunadarai tare da babban alaƙa da lipids (mafi girman log Kow) za a sauƙaƙe su ta hanyar shayarwa saboda yawan lipid na madara.[3] Ba a fahimci canja wurin abubuwa masu guba daga mai zuwa madara ba, kuma an lura da canja wurin gurɓataccen abu.
Ma'auni mai guba yana da wahala a lokacin shayarwa saboda madara lipids da suka samo asali daga blubber lipids da kuma hada su a cikin nama na mama. Canjin da ke cikin narkewar mai guba tsakanin mai da ruwa mai zagayawa da kuma rushewa da resynthesis na ƙwayoyin ƙwayoyin cuta da ƙwayoyin jini suna ba da gudummawa ga matsalolin ma'aunin ma'auni na masu guba tsakanin ƙwayoyin, da ke zagayawa, da ƙwayoyancin madara [4]
Koyaya, koda tare da matsalolin daidaitaccen taro, an lura da shi gabaɗaya a cikin hatimi mai launin toka da porpoises na tashar jiragen ruwa cewa ragowar a cikin lipids na mai na jariri gabaɗaya iri ɗaya ne ko dan kadan fiye da lipids na madara, kuma kusan rabin ragowar ne a cikin lipides na mai na uwa.[2][5]
Canjin Placental
[gyara sashe | gyara masomin]Canjin POPs daga uwa zuwa tayin ta hanyar placenta bai kai na lactation ba amma har yanzu yana iya haifar da mummunan sakamako.[6] Ana jigilar ƙwayoyin ƙwayoyin cuta daga plasma na uwa ko dai ta hanyar watsawa ko jigilar aiki ta hanyar kwayar halitta don amfani da su a cikin mahimman matakai kamar ci gaban kwakwalwa.[7] Tushen fatty acids galibi ana samo su ne daga mai a cikin hatimi, porpoises, da whales.
Ana iya canja wurin sunadarai na lipophilic kamar PCBs da aka adana a baya a cikin ƙwayoyin ƙwayoyin cuta na uwa zuwa tayin ta hanyar ruwa mai zagayawa. Wasu sunadarai na lipophilic ana iya sarrafa su ta hanyar tayin ta amfani da mafi yawan Enzymes na CYP, amma wasu ana sanya su cikin sauri a cikin ƙwayoyin ƙwayoyin cuta na tayin.[8][9] Adanawa da saki waɗannan sunadarai a cikin tayin na iya haifar da rushewar endocrine, immunosuppression, rushewar thyroid, da Neurotoxicity a cikin hatimi da orcas.[10]
Sakamakon
[gyara sashe | gyara masomin]Rashin Amfani da Yaran
[gyara sashe | gyara masomin]A cikin dabbobi masu shayarwa, ana iya canja wurin abubuwan uwa ta hanyar placenta, a cikin colostrum, da kuma a cikin madara ta al'ada yayin shayarwa. Yaran dabbobi masu shayarwa na ruwa suna da rauni musamman a lokacin da tsarin rigakafin su bai riga ya girma ba. Lokacin da mata ke ba da madara ga 'ya'yansu, suna iya samun tasiri mai ban mamaki a kan lafiyar 'ya'ya a lokacin ontogeny, da kuma lokacin da' ya'yan suka girma.[11] Dabbobi masu shayarwa na mata suna ba da mafi yawan nauyin POP ga 'ya'yansu na fari, yayin da maraƙin yake cikin mahaifa kuma daga baya yayin shayarwa. Babban adadin POPs da aka canja zuwa ga zuriya da kuma saurin canja wurin, wani lokacin na iya tabbatar da kisa.[12]
Maza vs. Mata
[gyara sashe | gyara masomin]Nauyin POP da dabbobi masu shayarwa na ruwa na maza da mata ke ɗauka yana ƙaruwa tare da lokaci har sai sun kai shekarun balaga. Bayan wannan batu, nauyin da ke cikin maza ya ci gaba da girma, yayin da suke ci gaba da shan POPs daga abincin su. Koyaya, tare da dabbobi masu shayarwa na mata, nauyin POP da aka ɗauka yana raguwa bayan haihuwa amma zai iya ƙaruwa har zuwa sake zagayowar haihuwa na gaba.[12]
Manazarta
[gyara sashe | gyara masomin]- ↑ Aylward, L. L.; Hays, S. M.; Kirman, C. R.; Marchitti, S. A.; Kenneke, J. F.; English, C.; Mattison, D. R.; Becker, R. A. (2014-01-01). "Relationships of chemical concentrations in maternal and cord blood: a review of available data". Journal of Toxicology and Environmental Health Part B: Critical Reviews. 17 (3): 175–203. doi:10.1080/10937404.2014.884956. ISSN 1521-6950. PMID 24749481. S2CID 21505371.
- ↑ 2.0 2.1 Addison, R. F.; Brodie, P. F. (1977-07-01). "Organochlorine Residues in Maternal Blubber, Milk, and Pup Blubber from Grey Seals (Halichoerus grypus) from Sable Island, Nova Scotia". Journal of the Fisheries Research Board of Canada. 34 (7): 937–941. doi:10.1139/f77-146. ISSN 0015-296X.
- ↑ Frouin, Héloïse; Lebeuf, Michel; Hammill, Mike; Fournier, Michel (2012-02-15). "Transfer of PBDEs and chlorinated POPs from mother to pup during lactation in harp seals Phoca groenlandica". Science of the Total Environment. 417–418: 98–107. Bibcode:2012ScTEn.417...98F. doi:10.1016/j.scitotenv.2011.11.084. PMID 22239965.
- ↑ Addison, R. F.; Brodie, P. F. (1987-04-01). "Transfer of Organochlorine Residues from Blubber through the Circulatory System to Milk in the Lactating Grey Seal Halichoerus grypus". Canadian Journal of Fisheries and Aquatic Sciences. 44 (4): 782–786. doi:10.1139/f87-095. ISSN 0706-652X.
- ↑ Heppleston, P. B. (1973-03-01). "Organochlorines in British grey seals". Marine Pollution Bulletin. 4 (3): 44–45. doi:10.1016/0025-326X(73)90305-6.
- ↑ Ren, Aiguo; Qiu, Xinghua; Jin, Lei; Ma, Jin; Li, Zhiwen; Zhang, Le; Zhu, Huiping; Finnell, Richard H.; Zhu, Tong (2011-08-02). "Association of selected persistent organic pollutants in the placenta with the risk of neural tube defects". Proceedings of the National Academy of Sciences (in Turanci). 108 (31): 12770–12775. Bibcode:2011PNAS..10812770R. doi:10.1073/pnas.1105209108. ISSN 0027-8424. PMC 3150927. PMID 21768370.
- ↑ Lager, Susanne; Powell, Theresa (2012). "Regulation of Nutrient Transport across the Placenta". Journal of Pregnancy. 2012: 179827. doi:10.1155/2012/179827. PMC 3523549. PMID 23304511.
- ↑ Prouillac, Caroline; Lecoeur, Sylvaine (2010-10-01). "The role of the placenta in fetal exposure to xenobiotics: importance of membrane transporters and human models for transfer studies". Drug Metabolism and Disposition. 38 (10): 1623–1635. doi:10.1124/dmd.110.033571. ISSN 1521-009X. PMID 20606001. S2CID 8134538.
- ↑ Szabo, AndrewJ.; Szabo, Olga (1974-08-31). "Originally published as Volume 2, Issue 7879PLACENTAL FREE-FATTY-ACID TRANSFER AND FETAL ADIPOSE-TISSUE DEVELOPMENT: AN EXPLANATION OF FETAL ADIPOSITY IN INFANTS OF DIABETIC MOTHERS". The Lancet. 304 (7879): 498–499. doi:10.1016/S0140-6736(74)92020-0. PMID 4137108.
- ↑ Krahn, Margaret M.; Hanson, M. Bradley; Baird, Robin W.; Boyer, Richard H.; Burrows, Douglas G.; Emmons, Candice K.; Ford, John K. B.; Jones, Linda L.; Noren, Dawn P. (2007-12-01). "Persistent organic pollutants and stable isotopes in biopsy samples (2004/2006) from Southern Resident killer whales". Marine Pollution Bulletin. 54 (12): 1903–1911. doi:10.1016/j.marpolbul.2007.08.015. PMID 17931664.
- ↑ "SeaWeb - Ocean Briefing Book". www.seaweb.org. Archived from the original on 2016-06-02. Retrieved 2016-05-23.
- ↑ 12.0 12.1 "Marine Chemical Pollution". WDC, Whale and Dolphin Conservation. Archived from the original on 2016-05-20. Retrieved 2016-05-23.