Thesis (M.S.)--University of Kentucky, 2004. / Title from document title page (viewed June 21, 2004). Document formatted into pages; contains vii, 112 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 104-110).

No description available.

Thesis (M.Tech.: Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2007 v, 125 leaves / Ruminants diets in most developing countries are based on fibrous feeds, mainly mature pastures and crop residues. These feeds are unbalanced and particularly deficient in protein, minerals and vitamins and are highly lignified with low digestibility. These characteristics result in low intake and productivity and only approximately 40% of energy in forage becomes available to the animal. Enzymes can be used as biological tool to enhance digestion through the action of cellulase, hemicellulase and lignase enzymes resulting in improved meat, milk and wool production. The development of feed additives holds great promise for the improvement of livestock growth and yield for both large commercial and smaller subsistence farmers. The aim of this study was to develop optimal media for the production of lignocellulolytic enzymes (laccases, xylanases, and cellulases) and to evaluate the application of these enzymes to improve the nutritional digestibility of high fibre feedstocks, such as veld grass.

In Fütterungs- und Verdauungsversuchen mit Hammeln und Milchkühen wurden die Futterwerteigenschaften von Nebenprodukten aus modernen Verfahren wie der Zucker-Bioethanol- und Rapsmethylesterproduktion beurteilt. Durch die Fütterung von Milchkühen im Hochleistungsbereich mit 5,2 kg TM Roggenpressschlempe je Kuh und Tag wurde der Sojaextraktionsschrotverbrauch um 50 % gesenkt. Die im Hammelversuch ermittelten NEL-Gehalte für Roggenpressschlempe liegen zwischen 5,3 bis 5,5 MJ NEL je kg TM. In Verdauungsversuchen mit Milchkühen ergab sich für Lipicafett ein NEL-Gehalt von 18,4 MJ NEL/kg. Der Einsatz von 300 g Rohglyzerin je Kuh und Tag führte zu einer geringfügigen Erhöhung der Futteraufnahme von 0,4 kg TM je Kuh und Tag. Nach der Pansenbeutelmethode ermittelt, besitzt Roggenpressschlempe einen UDP-Anteil von 43 % und Weizentrockenschlempe von 25 %. Für Sojaextraktionsschrot, Rapsextraktionsschrot und Rapskuchen wurden nach dieser Methode UDP-Anteile von 39 %, 41 % bzw. 19 % ermittelt.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 227-244).

Thesis (M.Tech.: Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2007 v, 125 leaves / Ruminants diets in most developing countries are based on fibrous feeds, mainly mature pastures and crop residues. These feeds are unbalanced and particularly deficient in protein, minerals and vitamins and are highly lignified with low digestibility. These characteristics result in low intake and productivity and only approximately 40% of energy in forage becomes available to the animal. Enzymes can be used as biological tool to enhance digestion through the action of cellulase, hemicellulase and lignase enzymes resulting in improved meat, milk and wool production. The development of feed additives holds great promise for the improvement of livestock growth and yield for both large commercial and smaller subsistence farmers. The aim of this study was to develop optimal media for the production of lignocellulolytic enzymes (laccases, xylanases, and cellulases) and to evaluate the application of these enzymes to improve the nutritional digestibility of high fibre feedstocks, such as veld grass.

As limited prey availability and persecution by humans in response to livestock predation are key conservation concerns for the Cape leopard (Martins & Martins 2006), the present study aimed to provide more information regarding their feeding habits. The first objective was to determine whether the Cape leopard was subject to a change in their prey base and how they responded to the change. This was established by comparison of their current diet in the Cederberg and Gamka Mountains, determined by using scat analysis techniques, with a previous dietary assessment (Norton et al. 1986). The second aim was to provide a preliminary assessment of the prey preference of the Cape leopard and examine the utility of camera trap surveys to determine leopard prey preference. Leopard diet in the Cederberg and Gamka Mountains consisted largely of small- (1-10 kg) and medium-sized (10-40 kg) mammals; rock hyraxes (Procavia capensis) and klipspringers (Oreotragus oreotragus) were key prey items. In terms of regional variation in leopard diet, there was a significant difference in the average weight of prey utilized in the Cederberg and Gamka Mountains. Despite the importance of prey availability of suitable size, their flexibility in terms of prey size utilization reflected their ability to switch to smaller prey to fulfil their dietary requirements, when prey is limited. The study suggested a dietary shift, with significant variation in prey species utilization in both regions. The shift did not appear to be in response to prey scarcity, but rather a reduction in key prey species, particularly the rock hyrax. The shift involved an increase in the number of species utilized, and only a very small increase in livestock predation in both areas. There was however no significant variation in prey size category utilization. This demonstrated their dietary flexibility, as well as the importance of suitable prey sizes rather than the presence of specific prey species to fulfil their dietary requirements. The camera trap survey revealed a strong correlation between the number of camera trap days and the number of photographs taken of identifiable species. Variation of this correlation between different habitats supported the notion that individual images are a better unit to determine sampling efficiency than trap days. The camera trap survey also showed that small rodent availability was underestimated by camera trap surveillance, which resulted in poor prey preference estimation. It was therefore suggested that camera trap surveys be restricted to the surveillance of larger prey species (> 1 kg). By excluding small rodents from the analysis, prey preference could be estimated for other species and prey size categories. Small- and medium-sized mammals were significantly preferred, whereas large mammals were significantly avoided by the Cape leopard.

In an attempt to reduce the costs and turn around times experienced with outsourcing starch analysis in finished feed products, the company decided to invest in a NIR instrument to carry out such analyses in house. The particular instrument purchased by the company comes with a build in calibration for specific finished feed products and the main objective of this investigation was to evaluate whether the instrumentation and build in calibration gives reliable analyses of a finished poultry feed. The results obtained showed that : - The NIR results obtained have a positive bias compared to the theoretical (formulation specified value) and also to the value obtained by enzymatic starch analysis. - Despite the positive bias, the starch values were well within the allowable limits - Repeatability measurements on the data generated by two different analysts showed that while the percentage relative standard deviations obtained (< 1.0 percent) were well within the company specifications of percentage RSD < 5.0 percent, the inter sample repeatability showed small, but significant variation. - The results for intermediate precision showed that there is no statistically significant difference between the results obtained by two different analysts, nor was there any difference in the results of the same samples analysed at different time periods. - Reproducibility could not be evaluated due to the lack of another instrument within the company that were similarly set up as the instrument used for the investigation. This investigation has shown that, given the restrictions enforced by the build incalibration of the NIR instrument, the use of NIR for the analyses of the finished feed product is valid, but will require that careful attention be paid to data collection procedures.

No description available.