Thesis (Ph. D.)--University of Wisconsin, 1974. / Mimeography copy of typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 242).

Dissertation (M. Appl. Sc.) -- Lincoln University, 2009. / Also available via the World Wide Web.

Thesis (Ph.D.(Animal and Wildlife Sciences)) -- University of Pretoria, 2009. / Summary in English. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 106-110).

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xi, 90 p.; also includes graphics (some col.). Includes bibliographical references (p. 88-90). Available online via OhioLINK's ETD Center

Thesis (Mino). / Bibliography: leaves 131-136.

The literature concerning the nutritional content of white clover as a grazed herbage or conserved crop offered to dairy cattle and aspects of frothy bloat are reviewed. In the first nine week change-over design experiment the effect on milk production and behaviour of spring calving dairy cows grazing white clover/grass swards at contrasting sward heights were examined. Grazing the clover/perennial ryegrass sward to a height of 4 cm increased clover content, but reduced milk production. The 8 cm sward increased milk yields by 15.8%. This was accompanied by an increase in fat and protein yields. Grazing time and biting rate were increased on the 4 cm sward. Cows offered choice between sward types produced intermediate milk production values. A second change-over design experiment conducted over 12 weeks examined milk production and behaviour of spring calving dairy cows in early lactation grazing perennial ryegrass or White clover/perennial ryegrass swards alone or offered a choice between the two sward types or grazed on clover/perennial ryegrass during the day and perennial ryegrass at night. The inclusion of clover in the diet of the dairy cows significantly increased milk production, but reduced fat content. Protein content, fat and protein yields were increased. Cows offered a choice or mixed day and night grazing regime produced similar results, which were intermediate between the clover/ryegrass and perennial ryegrass treatments. Grazing time was increased on clover/perennial ryegrass swards. This experiment also 1 demonstrated the ability of cows to adjust their grazing time to maximise herbage intake. The third experiment compared the value in relation to milk production of three different buffer forages fed to spring calving dairy cows in late lactation grazing either clover/ryegrass or ryegrass swards. The forages were ryegrass and ryegrass/clover silages and ryegrass hay. Milk yield and composition were not affected by forage type, but intakes were higher for grass silage for cows grazing clover/ryegrass swards and visa versa. Hay OM intake was low. The final experiment conducted over the first 15 weeks of the grazing season studied the effect of energy:protein concentration of strawmix supplements on the productivity of spring calving dairy cows grazing a high white clover sward. Milk yields were increased by the provision of a strawmix supplement. The energy:protein ratio had a significant effect on milk composition except fat content. The high energy:high protein supplement tended to precipitate ruminal tympany (bloat), while the low energy:high protein supplement tended to reduce ruminal tympany on this clover based sward. These experiments have given some insight into the use of clover and stimulated questions which require further investigation to enable the farmer to safely incorporate clover into dairy farming systems.

No description available.

On the Red Sea coast of Saudi Arabia ponds utilising seawater drawn from wells have an average salinity of 43%o and temperatures ranging from 23-33°C. The present study has demonstrated that yields of up to 4.3 tonnes ha"' of the Indian white shrimp Penaeus indicus at 20 g size may be obtained in these ponds. P. indicus was isolated from local stocks (Gizan) and has now been cultured through several generations at the Fish Farming Centre. Present work has determined that the optimal salinity for larval culture is 30960 and for nursery culture 25-30960. The best stage for transfer from nursery to growout pond (43960) is about PL25. Comparison with biological data for P. indicus cultured elsewhere indicates that Red Sea populations may be preadapted to tolerate high salinities. The potential for artificial feeds to replace live feeds in P. indicus larval culture from Z1 to PL1 and PL5 using microencapsulated feeds, Nippai and Frippak has been investigated. Results reveal that 50% replacement with Nippai and Frippak is possible giving comparable growth to the control, but poorer survival. Also comparative growth trials were conducted with post larval P. indicus (PL5-PL30) spawned from Red Sea stock and cultured through larval stages on five feeds (Chaetoceros, Tetraselmis and Artemia). Post larvae were reared on commercial feeds: Taiwanese, Nippai, Frippak and 4 formulated feeds based on locally available ingredients at 28-30°C and at 3016 and 42i salinities. Feeding trials at 42% produced poor survival, but at 30% all treatments gave over 50% survival to PL25, at which stage shrimp are ready for stocking in growout ponds. Although the Taiwanese feed produced the overall fastest growth, it was not significantly better (P > 0.05) than two locally formulated diets (FFC1,4) or Frippak. Survival rates of over 60% where achieved on all diets with the exception of Nippai and Taiwanese feeds. Yields were significantly higher (P < 0.05) on one of the locally prepared diets (FFC1) than Taiwanese and Nippai, and Taiwanese than Nippai. All diets yielded significantly more shrimp biomass at 30960 than 4216 (P > 0.05). The relative costs of imported and locally produced diets are discussed and it is concluded that it is possible to produce cost-effective nursery diets in Saudi Arabia. A growout feeding study for P. indicus juvenile utilising 4 locally formulated diets compared with a Taiwanese diet revealed no significant difference (P. > 0.05) in survival nor in growth or yield amongst all diets. However growth was slow due to low pH and high ammonia levels. Finally shrimp density production trials at 20, 40,60 and 80m"2 during winter and summer were conducted in cages placed in a rubber lined pond. For all densities; yields were significantly higher in summer than winter with an overall average of 3.41±1.5 tonnes and 4.04±2.36 tonnes 180 days-- for winter and summer respectively. Yield at 80m'1 was highest but was not different from yield at 60m'2. Based on average harvested size and market price the density of 60. =was regarded suitable for growout culture.

Food safety is an important issue facing consumers, the food industry and the government. Since consumers cannot themselves easily assess food safety risks, their perception of food safety is in part a matter of trust in the food chain. This study focuses on livestock farmers and investigates the causal relationship between the factors which determine consumer trust regarding food safety and in turn their purchase likelihood. The main research questions are: 1) What are the key factors which build consumer trust in this context? 2) What are the contributions of these factors to building consumer trust? 3) Is there any relationship between consumer trust and purchase likelihood? By integrating theories developed in several disciplines, six factors, namely: providing information, competence, integrity, benevolence, credibility and reliability were identified to have a strong influence on consumer trust in livestock farmers. An exploratory study in the form of face-to-face interviews was carried out to clarify the main concerns of livestock husbandry practices, and to identify the items to measure the causal factors of consumer trust in livestock farmers regarding food safety. Because the objectives set out in this study could not be achieved by using multiple regression, which could not handle latent variables, the conceptual model was tested with a quota sample of 194 individuals in the form of a Structural Equation Model using LISREL 8.30. It was proved successful in identifying the effects of the causal factors of trust to build consumer trust and in turn to affect purchase likelihood. The factor ‘providing information’ was identified to be a key factor by which trust is built and the features that lead to trust, namely: ‘competence’, ‘integrity’, ‘credibility’, ‘reliability’, and ‘benevolence’ were identified to be factors to build trust in livestock farmers. Representatives of the livestock industry were approached to confirm the relevance of the study and facilitate the interpretation of the findings. Though there is a limitation of its generalisation due to the sampling method, there is evidence that these factors are important to building consumer trust in livestock farmers regarding food safety. The evidence also suggests that there is a strong relationship between trust and consumer purchase likelihood. The research confirms that livestock farmers could draw benefit from strategies to increase their trustworthiness and in turn positively influence consumers’ purchasing decision. This study recommends further research to apply this model in other industries where the suppliers have little contact with consumers. The differences in trust building between cultures and the communication channels that livestock farmers representatives should used are also suggested for further study. Future research on how the food industry should respond to the change in consumer trust during periods of concern about food safety is also recommended. These are valid topics for future research and will provide potential benefits for consumers and food industry as a whole.