Gurasar ciki

Enteric fermentation tsari ne na narkewa wanda microorganisms ke karya carbohydrates zuwa kwayoyin masu sauƙi don sha a cikin jinin dabba. FAO ta kiyasta cewa dabbobi masu shayarwa suna ba da gudummawa ga kusan kashi 34.5 cikin dari na jimlar hayakin methane na mutum.

## Masu Raminants
Dabbobi masu tsinkaye sune wadanda ke da rumen. Rumen wani ciki ne mai ɗakuna da yawa wanda aka samo kusan kawai a tsakanin wasu dabbobi masu shayarwa, kamar shanu, tumaki, da dabbobi, wanda ke ba su damar cin tsire-tsire masu tsayi da hatsi waɗanda ke da ɗakuna guda ɗaya (watau, dabbobi masu ɗakuna guda), kamar mutane, karnuka, da Cats, ba za su iya narkewa ba. Kodayake ana zaton raƙuma ne ruminants ba ruminants na gaskiya ba ne.

Enteric fermentation yana faruwa ne lokacin da aka samar da methane (CH4) a cikin rumen yayin da fermentation na microbial ke faruwa. Fiye da nau'ikan microorganisms 200 suna cikin rumen, kodayake kusan 10% ne kawai daga cikin waɗannan ke taka muhimmiyar rawa a cikin narkewa. Yawancin kayan CH4 da dabba ta shafa. Koyaya, ana samar da ƙaramin kashi na CH4 a cikin babban hanji kuma ya wuce a matsayin flatulence.

Fitar da iskar methane muhimmiyar gudumawa ce ga hayaki mai gurbata yanayi a duniya. IPCC ta ba da rahoton cewa methane ya fi sau ashirin tasiri kamar CO2 a tarko zafi a cikin yanayi - ko da yake lura cewa an samar da shi a cikin ƙananan adadi. Methane yana wakiltar babban asarar makamashi ga dabba daga kashi 2 zuwa 12% na yawan kuzarin kuzari. Don haka, rage yawan samar da CH4 mai shiga jiki daga naman sa ba tare da canza noman dabbobi ba yana da kyau duka a matsayin dabarun rage hayaki mai gurbata yanayi a duniya da kuma a matsayin hanyar inganta ingantaccen canjin abinci. A Ostiraliya dabbobin daji sun kai fiye da rabin gudummawar iskar gas da suke bayarwa daga methane.

Koyaya, a Ostiraliya akwai nau'ikan ruminant na Kangaroos waɗanda ke iya samar da kashi 80% ƙasa da methane fiye da shanu. Wannan shi ne saboda microbiota na ciki na Macropodids, rumen da sauran sassan tsarin narkewar su, sun mamaye kwayoyin cuta na dangin Succinivibrionaceae. Wadannan kwayoyin suna iya samar da succinate a matsayin samfurin ƙarshe na lalacewar lignocelluloses, suna samar da ƙananan methane a matsayin samfurin ƙarshen. Hanyar metabolism ta musamman tana ba da damar amfani da wasu masu karɓar proton, guje wa samar da methane.

## Gudanar da gwaji
Enteric fermentation shine tushen mutum na biyu mafi girma na hayakin methane a Amurka daga 2 zuwa 2. A cikin shekara ta 2007, hayakin methane daga fermentation na ciki ya kasance 2.3% na iskar gas da aka samar a Amurka a 139 teragrams na kwatankwacin carbon dioxide (Tg CO2) daga cikin jimlar hayakin 6087.5 Tg CO2. Saboda wannan dalili, masana kimiyya sun yi imanin cewa, tare da taimakon injiniyan microbial, amfani da microbioma don canza tsarin halitta ko na ɗan adam, zamu iya canza abun da ke cikin microbiota na rumen na masu samar da methane masu ƙarfi, suna kwaikwayon Macropodidae microbiota. 

Bincike na baya-bayan nan ya yi iƙirarin cewa wannan dabarar tana yiwuwa a yi. A daya daga cikin wadannan binciken masana kimiyya suna nazarin canje-canjen microbiota na mutum ta hanyar canje-canjin abinci daban-daban. A cikin wani binciken, masu bincike sun gabatar da microbiota na mutum a cikin beraye na gnotobiotic don kwatanta canje-canje daban-daban don haɓaka sabbin hanyoyi don sarrafa kaddarorin microbiota don hana ko magance cututtuka daban-daban.

Wata hanyar sarrafa hayaki na methane daga fermentation na ciki ya haɗa da amfani da kayan abinci da kari a cikin abincin shanu. Misali, *Asparagopsis taxiformis* (wanda aka fi sani da ja seaweed) nau'in algae ne wanda lokacin da aka ciyar da shanu ya nuna cewa yana rage yawan hayakin methane a cikin wuraren kiwo. Misali na biyu wanda aka nuna don rage hayakin methane daga shanu sosai a cikin wuraren ciyarwa ya haɗa da amfani da fili 3-nitroxypropanol (3-NOP) wanda ke hana mataki na ƙarshe na kira na methane ta microorganisms a cikin rumen. Wasu daga cikin wadannan hanyoyin an riga an amince da su don amfani da manoma,  yayin da wasu ke ci gaba da kimantawa don aminci, inganci, da sauran damuwa.  Wadannan hanyoyin sun zo tare da iyakancewa yayin da hayakin hayaki na wakiltar kusan 11% na hayakin shanu gaba ɗaya.

## Dubi kuma

* Tasirin muhalli na samar da nama # Greenhouse gas
* Methane na sararin samaniya

## Manazarta