RESUMO
Three Korean native steers (779±24 kg) fitted with duodenal cannulas were used in a 3×3 Latin square design to investigate the influence of oral administration of soluble proteins, intact casein (IC) and acid hydrolyzed casein (AHC), on gastrointestinal hormone (GIH) secretion in the blood and pancreatic α-amylase activity in the duodenum. Oral treatment consisted of a basic diet (control), IC (C+100% protein), or AHC (C+80% amino acid, 20% peptide) for 21 d. Blood and duodenum samples were collected for measurement of serum GI hormones, and pancreatic α-amylase activity was determined at 900, 1030, 1330, 1630, and 1930 h after feeding on d 21 of treatment. The levels of serum cholecystokinin (CCK) and secretin in the IC treatment group were higher compared to the other treatment groups (p<0.05). In addition to the changes in CCK and secretin levels upon IC treatment, the pancreatic α-amylase activity in the duodenum was higher in the IC group compared to the control diet group (p<0.05). The response of serum ghrelin to IC and AHC treatment was in accordance with the response of serum secretin. The level of peptide fragments flowing in the duodenum was higher in the IC treatment group than the other treatment groups (p<0.05). In conclusion, this study demonstrated that an increase in duodenal CCK and secretin upon IC oral administration increased pancreatic α-amylase secretion. In addition, ghrelin may be associated with GI hormone secretion in Korean native steers.
RESUMO
The Formosan wild boar () is an endemic subspecies in Taiwan. Understanding the origins and spread of the Formosan wild boar could help clarify East Asian wild boar dispersion. Although in situ domestication of the wild boar occurred at a number of domestication centers across East Asia, corroborating archaeological and genetic evidence of pig domestication on Taiwan is lacking, leading to domestication being described as cryptic. This characterization applies to the Lanyu pig-a domestic pig breed found on Taiwan. To better understand pig domestication, this study examines the sympatric Formosan wild boar and domestic Lanyu pig to build a model of potential wild boar domestication on Taiwan and elucidate wild boar domestication patterns in the region. To this end, a comprehensive phylogenetic study of the Formosan wild boar and the Lanyu pig was conducted on animals sourced from Taiwan, Lanyu, and the Philippines. Phylogenetic analyses were conducted using full mitochondrial control-region sequences from 345 wild boars and domestic pigs. These were studied in concert with existing reports on 206 Asian wild boars. Genetic characteristics and Bayesian phylogenetic tree results identified 2 wild boar lineages of remote phylogenetic relationship. These were Formosan wild boar lineage (FWBL) and Formosan wild boar with Lanyu sign lineage (FWBLYL). Molecular clock analyses indicate that FWBLYL diverged earlier than other insular East Asia wild boars and show that FWBLYL and FWBL diverged approximately 0.60 million years ago. This result supports boars of FWBLYL being the earliest wild boars to have spread and become isolated in insular East Asia. In addition, the study proposes 6 Asian wild boar dispersion routes during glacial periods. At least 3 of these events occurred in insular East Asia with subsequent geographical isolation after glacial recession. This isolation potentially led to allopatric differentiation of wild boar subspecies. Also, the similar genetic signature and phylogenetic uniqueness of Lanyu pigs to wild boars of FWBLYL suggests such wild boars were the wild ancestor of domestic Lanyu pigs. This result indicates potential in situ domestication occurring on Taiwan. Finally, pigs possessing FWBLYL's genetic signatures were continuously distributed among Taiwan, Lanyu, and the Philippines. This pattern may signify human-mediated pig dispersal routes.