Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 36-38).

Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

In poultry housing where the light environment is provided artificially, it is largely designed to meet the requirements of human vision and poultry production and does not necessarily consider the bird's visual abilities. Extrapolation of research from fowl to other poultry species may be inappropriate, given their different ecological backgrounds. The overall aim of this thesis was to investigate vision in domestic ducks and turkeys and their light requirements. The spectral sensitivity of domestic ducks, domestic turkeys and humans was investigated using a behavioural test. Ducks and turkeys had similar spectral sensitivities, extending into the UVA part of the spectrum, with a broader range than humans. These results imply that the lux unit is inappropriate for describing the illuminance of a light source, as perceived by ducks and turkeys. The light environment in commercial duck and turkey housing was surveyed: mean illuminance was 22.6 and 5.3 lux, respectively. The spectral power distributions of the light sources and the birds' spectral sensitivity were used to estimate illuminance as perceived by ducks and turkeys; this varied by up to ~20% depending on light source. In a preference test ducklings and turkey poults were given a free choice between illuminances of < 1, 6, 20 and 200 lux at two and six weeks of age. Ducklings spent least time in < 1 lux though this was not affected by age. Turkey poults showed an overall preference for 200 lux at two weeks and 2:20 lux at six weeks. For both species, illuminance significantly affected the partition ofbehaviours. These results show that domestic ducks and turkeys have good colour vision, including UVA perception, and have distinct illuminance preferences. They imply that full spectrum lighting of varying temporal or spatial illuminance in housing might benefit welfare and satisfy preferences. Future work is needed to assess the use of UVA radiation by poultry and the strength of their motivation for illuminance.

A dissertation submitted in partial compliance with the requirements for the Master's in Technology: Homoeopathy, Technikon Natal, 1998. / During the six-week life span of broiler chickens, stress, vaccination reactions and disease may lead to poor feed conversion efficiency and increased mortality rates. The purpose of this study was to determine whether homoeopathic medicines would influence the feed conversion efficiency, mortality rates and incidence of infectious coryza and related respiratory syndromes in broiler chickens. / M

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A comparison was made of rates of growth and body weights between pre- and post-hatching stages of development of the chicken as affected by strains or strain crosses, egg storage, egg weights, time of hatch, sex and post-hatching nutritional environment. The interrelationships of these factors were also investigated. The results of the investigation indicate that practically all of the variation of six-week body weight in this data was successfully accounted for by the combined effects of six-week growth rate, hatching weight and embryonic growth rate between eight and twelve days. The data also indicate that gains in six-week body weight may be made by selecting for early growth rate without concomitant change in other traits. Hatching time, hatching weight and post-hatching growth appear to be affected by egg storage only if some form of stress is present during incubation. In the absence of stress it appears that a compensatory increase in rate of embryonic growth overcomes the effect of a delayed initiation of growth caused by egg storage. A significant influence of sex on embryo weight in favour of the male embryos was observed. / Land and Food Systems, Faculty of / Graduate