Call number: LD2668 .T4 1949 E15 / Master of Science

Call number: LD2668 .T4 1952 O7 / Master of Science

LD2668 .T4 1954 R65 / Master of Science

LD2668 .T4 1965 W753 / Master of Science

No description available.

No description available.

No description available.

Physiological, behavioral and production traits of White Leghorn cockerels from lines selected for high and low antibody response to sheep red blood cell antigen were measured to 70 days of age in several husbandry settings. Chicks were reared in pens with wood shavings, in windowless rooms, with continuous light and feed and water available <i>ad libitum</i>. Socialization, to enhance chicken-human relationships, and auditory playbacks of contentment calls were used as husbandry procedures in the context of environmental enrichment. Socialization involved gentle handling of a sample of the birds while playbacks were of 30 minute duration. Both were conducted three times per week with socialization performed from 1 to 28 days and playbacks from 1 to 70 days of age. The experiment was a 2 x 2 x 2 factorial with two stocks, socialization-nonsocialization and playback-no playback. To minimize extraneous effects, the area where the flocks were located was restricted to personnel involved specifically with this experiment. That is, the same individual (usually John Michael Metz) who obtained the data also performed the routine husbandry. None of the husbandry settings appeared to create a stress as measured by heterophil/lymphocyte ratios and production of antibody to sheep erythrocytes. Behavioral and production criteria showed that chicks responded favorably toward socialization and playbacks as measured by feed conversion and comfort scores, with the effects of the stimuli paralleling each other. The lack of additivity suggests an optimum intermediate of stimuli. Contentment to distress call ratios decreased with age. Concomitantly there were increases in social encounters among flock-mates which were probably associated with the formation of peck-rights. Genotype by husbandry setting interactions were fairly common suggesting that the degree of response to these stimuli varies among populations. This result was not surprising because of the intense selection in closed chicken populations. The data suggest that playbacks of contentment calls or enhancement of the chicken-human relationships can increase the well-being of young flocks of chickens. The degree of response, however, may vary among populations. / M.S.

No description available.

<p>  </p> <p>There is a clear need for more research detailing how to manage birds in cage-free housing systems. Although management guides for birds in cage-free systems focus on adult hens, previous research has established that the pullet phase is important to success later in life. Past research regarding the effects of stocking density on behavior has focused on caged adult hens, and often deals with confounding factors such as group size, limiting its interpretation. The goal of this project was to investigate the impacts of stocking density on behaviors of pullets in cage-free housing systems. </p> <p>A 2x2 randomized complete block design with two strains (Lohmann LB-Lite (Brown) and Lohmann LSL-Lite (White)) and two stocking densities (619.1 (high stocking density; HSD) and 1,248.9 (low stocking density, LSD) cm2/bird) was utilized. Videos of 6 pens for each strain by stocking density combination (59 birds/pen, n = 1416) were recorded for 2 consecutive days at 12 and 16 weeks of age (WOA). Behaviors of interest were recorded every 10 minutes for 1 hour in the morning, afternoon, and evening. Most behavior data were analyzed using a mixed model, PROC GLIMMIX, in SAS 9.4 with main effects of stocking density (SD), strain, age and time of day (TOD). Behaviors that were infrequent or that could not be transformed to meet normality assumptions were analyzed as binomial data (occurred or did not occur) and odds ratios were calculated using PROC LOGISTIC.</p> <p>Stocking density influenced every behavior examined. The LSD had fewer birds that performed eating and drinking behaviors, but more birds performed inactive, locomotion, exploratory and comfort behaviors compared to the HSD. Additionally, birds in the HSD were more likely to participate in pecking and piling behaviors compared to LSD. These results suggest that LSD may provide welfare benefits to the pullets. However, producers may face economic barriers when attempting to decrease stocking densities. Further research is needed in this area, but these results could help to achieve a stocking density that maximizes the range of behaviors pullets are able to perform within the scope of a producer’s resources. Future directions may consider collecting behavior data across the life cycle in addition to examining the relationships among behavior and welfare parameters such as feather quality, foot condition and keel bone fractures.</p>