Različitost minutnog ritma tankog crijeva ovaca u odnosu na hranjenje i faze migrirajućeg mioelektričnog kompleksa

Autor: Krzysztof W. Romański
Jazyk: angličtina
Rok vydání: 2016
Předmět:
Zdroj: Veterinarski arhiv
Volume 86
Issue 3
ISSN: 1331-8055
0372-5480
Popis: The precise character of the ‘minute rhythm’ (MR), the common motility pattern occurring mostly in the small bowel, still remains to be elucidated. Since more complete information in this area can help to assess its physiological meaning and roles, myoelectrical recordings were performed in six rams equipped with bipolar serosal electrodes attached to the antral, bulbar, duodenal and jejunal (two electrodes) wall. In fasted and nonfasted rams, at least one full cycle of the migrating myoelectric complex (MMC) was recorded without and after feeding in long-term experiments. The MR patterns were identifi ed by recordings of myoelectrical activity. Food was administered during phase 2a or 2b of the MMC. The MR incidence and coordination were evaluated in four 5-minute periods. In the pyloric (abomasal) antrum, the MR was rarely observed in fasted and non-fasted animals, while after feeding, its identification was erratic. However, in fasted animals the incidence of the MR in the antrum was significantly higher during phase 2b compared with phase 2a of the MMC. Its incidence was significantly higher in the duodenum during phase 2b compared with phase 2a of the MMC in non-fasted rams, before and after feeding. In the duodenal bulb and the duodenum, the pattern was most frequently observed independently of feeding conditions. In the jejunum, one MR cycle usually comprised more than one or two spike bursts, so that when the myoelectric activity was more intense, its identification was sometimes uncertain. The MR was often absent on the distal jejunal recording channel. In the upper segments examined the MR was the most distinct and migrated regularly between adjacent sites. During phase 2b, the MR incidence was slightly higher than during phase 2a of the MMC. Feeding increased MR incidence significantly, but these changes were more evident during the initial observation periods. It was concluded that the diversity of MR is high which may result, at least in part, from the limited influence of feeding and the MMC phase upon the pattern.
Točno obilježje „minutnog ritma“ (MR), načina motiliteta osebujnog za tanko crijevo, još uvijek nije posvema razjašnjeno. Budući da više potpunih informacija na ovom području može pomoći u procjeni njegova fiziološkog značenja i uloge, poduzeto je mioelektrično snimanje na šest ovnova kojima su bipolarne elektrode stavljene na antralnu, bulbarnu, duodenalnu i jejunalnu (dvije elektrode) stijenku. U trajnim pokusima u izgladnjelih i neizgladnjelih ovnova bio je snimljen najmanje jedan potpuni krug migrirajućeg mioelektričnog kompleksa (MMK) s hranjenjem i bez hranjenja. Obilježja MR identificirana su na snimkama mioelektrične aktivnosti. Hrana je ovnovima bila dana tijekom faze 2a ili 2b MMK. Pojavljivanje MR i koordinacija bili su procjenjivani u četiri 5-minutnih razdoblja. U piloričkom (abomazalnom) antrumu MR bio je rijetko zabilježen u izgladnjelih i neizgladnjelih životinja, dok je nakon hranjenja bio nepravilan. Međutim, u izgladnjelih životinja pojavljivanje MR u antrumu bilo je značajno češće tijekom faze 2b u usporedbi s fazom 2a MMK u neizgladnjelih ovnova, prije i nakon hranjenja. U duodenalnom bulbusu i duodenumu MR je češće bio opažen neovisno o uvjetima hranjenja. U jejunumu je ciklus MR obično obuhvaćao više od jednog ili dva vrška prenapunjenosti, tako da ga se nije moglo sa sigurnošću identificirati kad je mioelektrična aktivnost bila pojačana. U distalnom jejunumu MR je često bio odsutan. U gornjim dijelovima MR je bio najizraženiji i pravilno se izmjenjivao između susjednih područja. Tijekom faze 2b, incidencija MR bila je nešto viša nego tijekom faze 2a MMK. Hranjenje je značajno povećalo incidenciju MR, ali su te promjene bile očitije u početnom razdoblju promatranja. Može se zaključiti da je raznolikost MR vrlo velika što, barem djelomično, može proizaći iz ograničenog utjecaja hranjenja i MMK faze.
Databáze: OpenAIRE
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