3 resultados para Co-feeding
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
Male Sprague-Dawley rats were fitted with two cannulae in the VTA and one cannula in the NTS for co-administration of the mu-opioid receptoragonist DAMGO in one site and the opioid antagonist naltrexone in the other. Injection of DAMGO into the VTA or the NTS stimulated feeding. The increase in food intake after DAMGO injection into the VTA was decreased following injection of naltrexone into the NTS. Furthermore, the increase in food intake after DAMGO injection into the NTS was decreased following injection of naltrexone into the VTA. These results suggest an opioid-mediated feeding association between the VTA and NTS. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
Mixed flocks of pale-bellied Brent geese (Branta bernicla hrota) and wigeon (Anas penelope L.) feeding on intertidal Zostera spp were studied during October 1993 with respect to tidal position, feeding method and duration, and competitive: interactions within and between species. Owing to many disturbance incidents affecting the use of the site by wildfowl, only complete data on flow tides were presented. Brent geese fed over a greater period of the tidal cycle than wigeon. Differences in feeding methods indicated that Brent geese exploited the rhizomes, which are energetically more profitable than the shoot on which wigeon fed. Aggressive interactions were recorded within species but there were no records of aggression between species. More subtle competition for space, however, may have occurred during feeding. Brent geese could reach Zostera spp For a short period after increasing depth of water prevented access by wigeon. However, individual wigeon were observed foraging near feeding Brent geese, picking up the scraps oi material discarded by the latter, and small numbers of wigeon may benefit from the presence of the geese. These benefits for some individual wigeon are not considered to compensate for the disadvantages to the latter species population as a whole in feeding on poorer-quality food for a shorter period of the tidal cycle. This disadvantage is likely to have contributed to the decline in the wigeon population on Strangford Lough, Co. Down, while numbers of Brent geese have been maintained at a high level.
Resumo:
Children consuming maize based foods in Tanzania may be exposed to multiple mycotoxins. We estimated co-exposures of aflatoxins with Deoxynivalenol (DON) and fumonisins for children in rural Tanzania. Food consumption by the children was estimated by twice administering a 24 h dietary recall questionnaire to mothers of 18-24 months old children in Kikelelwa village. Each mother also; provided a sample of maize based flour used for feeding her child in the previous day. Each child's body weight (bw) was measured by following standard procedures. Aflatoxins, DON and fumonisins were determined in each sample using validated HPLC methods. Exposures for a mycotoxin were estimated by multiplying flour consumption (g/child/kgbw/day) by its contamination (mu g/kg). Complete data were obtained for 41 children. Maize flour consumption ranged from 16 to 254 g/child/day. Thirteen (32%) of the 41 children consumed flour with detectable aflatoxin levels (range, 0.11-386 mu g/kg), resulting in exposures from 1 to 786 ng/kg bw/day. All these children exceeded the aflatoxins exposure of concern (0.017 ng/kg bw/day). Eighteen (44%) of the children consumed flour with detectable DON levels (57-825 mu g/kg) and 34(83%), detectable fumonisins levels (63-2284 mu g/kg), resulting in respective exposure ranges of 0.38-8.87 mu g/kg bw/day and 0.19-26.37 mu g/kg bw/day. Twelve (66%) of the DON exposed children and 56% of the fumonisins exposed children exceeded the respective provisional tolerable daily intakes of 1 mu g/kg bw and 2 ng/kg bw. Co-exposures for aflatoxins with both DON and fumonsins were determined in 10% of the 41 children. Co-exposures of aflatoxins with fumonisins alone were found in 29% and of fumonisins with DON alone in 41% of the children. The study showed that children consuming maize based complementary foods in Northern Tanzania are at a risk of exposure to multiple mycotoxins. We recommend adoption of appropriate measures to minimize exposures of multiple mycotoxins in Tanzania. (C) 2014 Elsevier Ltd. All rights reserved.