Call number: LD2668 .T4 1939 G51 / Master of Science

LD2668 .T4 1948 C48 / Master of Science

No description available.

Numerous properties of Yucca schidigera and Quillaja saponaria have been studied with respect to the saponins in the plant. These saponins are present in the extract as well and have been utilized commercially in the food and cosmetic industry for various products. Saponins have detergent-like properties in the presence of water. The detergent-like behavior of saponins plays a major role in their membranolytic properties. In addition, emulsification effects on fat which are characteristic of surfactant-type substances, may occur as well. Three studies were conducted using adult roosters, growing broiler chicks, and growing Japanese quail. Various effects of supplementing Yucca schidigera in the diets of these birds were studied such as: growth performance, overall health, and nutrient availability. An additional experiment was conducted comparing effects of Quillaja saponaria and Yucca schidigera extracts on body weight and fat digestibility in adult roosters. Addition of Yucca schidigera extract to high fat diets (tallow-based) increased lipid excretion in roosters, broilers, and quail. In roosters, dose of yucca extract affected excretion of lipid but no dose effects were seen in broilers or quail. Fat digestibility was not significantly affected by addition of saponins to the diet of adult roosters. However, fat digestibility was reduced in broilers and quail consuming a high fat diet. In general, level of dietary fat seemed to play a role in the effects of Yucca schidigera supplementation in growing birds. Addition of Yucca schidigera to high fat diets resulted in decreased plasma levels of vitamin A and E in broiler chicks. / Graduation date: 2000

No description available.

No abstract provided / Dissertation (MSc (Agric) Nutrition)--University of Pretoria, 2005. / Animal and Wildlife Sciences / unrestricted

No description available.

The influence of microbial phytase on growth performance, availability of macro and trace minerals, apparent ileal digestibility (AID) and apparent "fecal" digestibility (AFD) of amino acids (AA) and CP were investigated. The optimum level of dietary Ca and P for the maximum efficacy of supplemental phytase in broiler chickens was also studied. Phytase supplementation (600 U/kg) to a low P diet increased $(P 0.05)$ on feed efficiency in broiler chickens at 21 d. The efficacy of phytase, particularly in stimulating growth, was higher in male than female chickens. The relative retention of Ca, P, Cu, Zn and N increased by addition of phytase to a low P diet but phytase had no effect $(P >0.05)$ on the retention of Mg, Mn and Fe. Phytase supplementation increased $(P 0.05)$ on plasma Zn, Cu, and Mg. Phytase increased $(P 0.05)$ on mineral proportions in the tibia ash; however, it increased $(P 0.05)$ on AID of any of the AA in male chickens. Addition of phytase did not have any effect $(P > 0.05)$ on AFD of any of the AA in male chickens but increased $(P 0.05)$ on either AID or AFD of CP and AA at 21-d. In summary, phytase supplementation increased the growth performance, availability of P, Ca, Cu, Zn and N, plasma P, and tibia ash and reduced plasma Ca; it also increased the AID and AFD of most of the AA, particularly in female chickens at 28-d. The efficacy of microbial phytase was high when dietary P and Ca levels were low.

Two growth trials were designed to measure the effects of: (1) dietary Virginiamycin (0 or 16.5 mg/kg) and added fat (0 or 4%), and (2) Virginiamycin (0 or 16.5 mg/kg) and dietary lysine levels (low, NRC, high) individually, and in combination on broiler performance. A third trial investigated the relationship of plasma glucose, triglyceride and phospholipid concentrations with degree of fatness/leanness in genetically lean and fat broiler chickens. A combination of supplemental fat and Virginiamycin increased protein and decreased fat content of the dressed carcass. Virginiamycin supplementation overcame the growth depression of a low lysine diet by increasing feed intake. In the low lysine diet, Virginiamycin supplementation reduced abdominal fat deposition in females and increased carcass yield in males. Carcass protein content was increased by feeding the NRC-recommended level of lysine or by Virginiamycin supplementation. (Abstract shortened by UMI.)

Made available in DSpace on 2014-06-11T19:27:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-29Bitstream added on 2014-06-13T19:35:20Z : No. of bitstreams: 1 casagrande_mf_me_jabo.pdf: 218142 bytes, checksum: 6ef7c320b8bdbaed3b6341196a855458 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Com a proposta de avaliar os efeitos de produtos químicos sobre a inibição de Clostridium perfringens inoculado experimentalmente em ingredientes de ração, conduziu-se três experimentos. No primeiro experimento objetivou-se verificar a presença de C. perfringens em amostras de quatro ingredientes de ração. No segundo, o objetivo foi analisar a eficiência do Salmex® (uma mistura de formaldeído e ácidos orgânicos), em seis concentrações diferentes, utilizando dois ingredientes de ração em dois períodos após inoculação experimental de C. perfringens, já no terceiro avaliou-se o efeito de produtos à base de formaldeído e de ácidos orgânicos frente ao desafio experimental de C. perfringens em ingredientes de ração. Para a realização da verificação da presença de C. perfringens em farinha de carne/ossos, farinha de sangue/penas, farinha de vísceras e a mistura vegetal (60% de quirera de milho e 40% de farelo de soja), foi utilizado ágar DRCM incubados a 37°C por 48h em anaerobiose. Para os outros experimentos foram realizados a contagem de C. perfringens em dois períodos de ação, 24h e 5 dias, porém para o experimento com diferentes concentrações do Salmex® foram usados apenas dois ingredientes: a mistura vegetal e a farinha de carne/ossos, as concentrações desse produto variaram de 1,0g/kg a 6,0g/kg. Já para o experimento envolvendo três produtos: formaldeído, ácidos orgânicos e Salmex®, foram utilizados quatro ingredientes: mistura vegetal, farinha de carne/ossos, farinha de sangue/penas e farinha de vísceras. Para ambas as contagens, foi usado ágar SPS a 37°C por 48h em anaerobiose. Foi isolado C. perfringens em 60% das amostras. O Salmex® diminuiu a contagem da população de C. perfringens nas amostras que receberam doses acima de 3g/kg, sendo mais eficiente no período de cinco dias... / This experiment had the purpose of evaluating the effects of chemicals on the inhibition of Clostridium perfringens in food ingredients, we conducted three experiments. In the first experiment aimed to verify the presence of C. perfringens in four samples of feed ingredients. In the second, the goal was to analyze the efficiency of Salmex® (a mixture of formaldehyde and organic acids) in six different concentrations using two feed ingredients in two periods after experimental inoculation of C. perfringens, since the third evaluated the effect of formaldehyde-based products and organic acids compared to the experimental challenge of C. perfringens in feed ingredients. To perform the verification of the presence of C. perfringens were used meat meal / bone meal, blood / feathers, poultry meal and vegetable mix (60% of corn grits and 40% soybean meal), was used for this DRCM agar incubated at 37°C for 48h under anaerobic conditions. For other experiments were performed to count C. perfringens in two periods of action, 24 hours and 5 days, but to experiment with different concentrations of Salmex® were used only two ingredients: the flour mixture and vegetable meat / bone, the concentrations of the product ranged from 1,0g/kg to 6,0g/kg. For the experiment involving three products: formaldehyde, organic acids and Salmex®, we use four ingredients: vegetable mix, meat / bone meal, blood / feathers and poultry meal. On both counts, was used SPS agar at 37°C for 48h under anaerobic conditions. The Salmex® reduced the population counts of C. perfringens in samples that received doses of above 3,0g/kg, being most effective in the period of five days. There were significant differences between products and time of action (p<0,0001), but no difference was found among the ingredients (p=0,0580)... (Complete abstract click electronic access below)