ETD Collection

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Author: search.filters.author.Donaldson, JanineHas files: Yes

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    The physiological responses of Guinea fowl, muscovy ducks and Japanese quail to high-fat diets
    (2016) Donaldson, Janine
    Animal fats and vegetable oils are often added to poultry diets to improve growth performance or to modify the lipid profiles and overall lipid content of the edible bird tissues to be consumed by humans. Effects of these high-fat diets (HFD) on the health status of birds during production are rarely investigated and most research involving current poultry production practices is performed in chickens and extrapolated to alternative poultry species. The current research investigated the effects of HFD feeding on the overall health status and tissue lipid profiles of some alternative poultry species which are becoming popular as table birds. Briefly, Guinea fowl (Numida meleagris), Muscovy ducks (Cairina moschata) and Japanese quail (Coturnix coturnix japonica) were fed a HFD rich in saturated fatty acids (Guinea fowl and Muscovy ducks) or HFDs of varying fatty acid profiles (Japanese quail) or a standard diet for a period of between four and twelve weeks. Oral glucose tolerance test parameters, erythrocyte osmotic fragility indices and serum metabolic health markers were used to assess the overall health status of the birds, following the HFD feeding. Liver lipid content, caecal microflora, organ masses, intestine lengths, the mass, length and relative density of the femurs, as well as the liver, breast muscle and thigh muscle lipid profiles were also assessed in the majority of the birds. The HFDs were well-tolerated by the birds, with no obvious adverse effects observed with respect to the health status of the birds. Dietary fatty acids were successfully transferred to the edible tissues of the Japanese quail and despite the very high level of lipid supplementation, the overall lipid content of the edible tissues remained within normal ranges. Thus if necessary, in terms of the modification of the edible tissue lipid profiles of poultry birds, HFDs of this nature can be used during poultry production without any adverse health implications for the birds. The birds should remain healthy during the feeding period, avoiding any additional production costs related to the maintenance of the birds’ health status. In terms of potentially increasing the overall lipid content of the edible bird tissues as a means of increasing the total amount of lipids ingested by humans, the significantly increased level of lipid inclusion used in the present study was unsuccessful in doing so. Thus, it seems that regardless of the increased lipid inclusion, the overall lipid content of the edible bird tissues is somewhat regulated within a certain range. Future studies should focus on the mechanisms responsible for the resilience of these birds to the HFD feeding and the mechanisms involved in the regulation of the overall content of lipid deposition within the edible bird tissues.
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    Growth performance and digestibility in exocrine pancreatic insufficient pigs supplemented with a pancreatic enzyme preparation
    (2009-05-26T08:05:21Z) Donaldson, Janine
    Exocrine pancreatic insufficiency (EPI) is a major complication of cystic fibrosis. Conventional treatment involves the replacement of pancreatic enzymes and intake of a low fat diet. However, contrary to previous therapeutic strategies, a high fat diet may be beneficial in EPI patients. The present study investigated the effects of dietary supplementation with Creon 10 000 a pancreatic enzyme preparation, in conjunction with a high-fat diet, on growth performance, digestibility and absorption of fat in a pig model of EPI by the surgical ligation of the pancreatic duct in 6 male pigs (Swedish Landrace X Yorkshire X Hampshire). Following surgery, and for the duration of the experimental period, pigs were fed a high fat diet (twice daily). The experimental period lasted for 15 days during which blood, urine and faecal samples were collected. In the last 7 days of the experimental period (days 8-14), Creon 10 000 was included in the high fat meals. Urine and faecal samples were analysed for dry matter, crude protein and fat content. Plasma was used to assess the lipaemic index and the plasma lipid profiles. Treatment with Creon 10 000 significantly increased body mass (P = 0.016) and the digestibility of dry matter, crude protein as well as the co-efficient of fat absorption were also significantly improved following treatment (P<0.05). Creon 10 000 improved the lipaemic index values and significant changes in plasma free fatty acid and triglyceride concentrations were observed but not in cholesterol or high and low density lipoproteins. This study supports previous reports that the administration of pancreatic enzyme preparations together with a high fat meal is a beneficial strategy for the nutritional management of EPI.