Veterinarski arhiv, Vol. 86 No. 3, 2016.
Izvorni znanstveni članak
The diversity of ‘minute rhythm’ forms in the ovine small bowel: relationship to feeding and to the phase of the migrating myoelectric complex.
Krzysztof W. Romański
; Department of Biostructure and Animal Physiology, Faculty of Veterinary Medicine, Wrocław, University of Environmental and Life Sciences, Wrocław, Poland
Sažetak
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.
Ključne riječi
ram; abomasal antrum; duodenal bulb; duodenum; jejunum; migrating myoelectric complex; minute rhythm; fasting; feeding
Hrčak ID:
160974
URI
Datum izdavanja:
10.6.2016.
Posjeta: 893 *