Dressed, bagged whole chickens from three Oregon and several out-of-state processors were purchased from retail markets in each season in 1988. Birds were stored at 3°C for 6 days. Total aerobic microorganisms, total psychrotrophic microorganisms, pseudomonads and fluorescent pseudomonads were determined by appropriate procedures. Total aerobic microorganisms and psychrotrophic microorganisms were counted on standard plate count agar with incubation at 20°C for 3 days and at 5°C for 7 days, respectively. Two media, King's B medium and CFC medium, were used in counting pseudomonads. Fluorescent colonies were observed on King's medium under ultraviolet light. A simple slime smear test was used to determine the sliminess. Sensory evaluation was done by thirteen panelists using 9-point scales. The flavor of cooked white and dark meat and skin, the flavor intensity of cooked white and dark meat and skin, the aroma of raw and simmered meat, the aroma intensity of raw and simmered meat and raw sliminess were evaluated. Simple regression analysis was used to determine the relationships between the microbial parameters and sensory evaluations. The paired t test was used in determining the difference between counts on King's medium and CFC medium. A significance level of 95% was set for all tests. Correlation coefficients were also calculated. All the microbial counts were at or below 10⁷/cm², which indicated from literature comparisons that most of the fryers purchased from retail markets and stored for six days were of acceptable quality. The season had no significant effect on the microbial counts and sensory qualities. The means of flavor of cooked meat and skin and aroma of raw and simmered meat were all above fair. Only the raw aroma intensity was significantly (p<0.05) and strongly correlated (r=-0.88) to the aroma quality. Relationships between microbial counts and flavor of cooked meat and aroma of raw and simmered meat were all significant but the correlations were weak. The narrow range of microbial counts may explain the weakness of the correlations found. The slime smear tests had a positive relationship (p<0.05) to the raw sliminess score by panelists, total aerobic microorganisms, total psychrotrophic microorganisms, pseudomonads, and fluorescent pseudomonads. / Graduation date: 1990

The objective of the study was to determine the effects of Aloe ferox inclusion in drinking water on growth performance, blood biochemistry, physico-chemical characteristics, fatty acid profile and oxidative stability of broiler meat. The importance of A. ferox as a medicinal plant and factors that influence its utilization by communal poultry farmers were also investigated by use of a questionnaire survey. The survey revealed that the majority of respondents (84.6%) faced health challenges in their chickens and many relied (96.2%) on A. ferox to treat diseases and control parasites. The study also revealed that the choice of medicine (traditional or conventional) was influenced (P<0.05) by level of education and income. In the second phase of the research, a total of 600 Ross 308 day-old broilers, were randomly put in 6 treatment groups with 4 replicates, each having 25 birds. Fresh aqueous A. ferox leaf juice (ALJ) was administered in drinking water at a dosage of 20ml/litre to T1, T2 and T3 from day one to day 35, day one to day 14 and day 15 to day 28, respectively. Birds in T4 and T5 (positive controls) were treated with terramycin at the recommended dosage of 14g/litre of drinking water from day one to day 6 and from day 15 to 20, respectively; and birds in T6 (negative control) received distilled water from day 1 to 35. Feed Intake (FI), average daily gain (ADG) and feed conversion ratio (FCR) were calculated for the 5 week trial. After slaughter, carcass characteristics particularly dressing percentage (DP) and relative organ weight (ROW) were calculated. Serum biochemistry was also determined. For meat quality, pH and color were recorded 45 minutes and 24 hours after slaughter from the breast muscle. Fatty acid profiling and oxidative stability were determined using meat samples from the breast and thigh muscles. The results for growth performance showed that thebirds which were given A. ferox for the first two weeks (T2) consumed significantly (P>0.05) more feed (189.4g) than those in the negative control (159.6g) at the beginning of the starter phase. Subsequently, their ADG recorded on day 7 (27.1g) and day 14 (43.1g) were significantly (P<0.05) higher than the negative control (22.8g and 36.2g, respectively). Significant treatment effects (P<0.05) for FCR were reported in the 4th week for the birds that received A. ferox throughout (T1: 3.5). Carcass characteristics were not significantly (P>0.05) affected by A. ferox inclusion in drinking water. The highest high density lipoprotein (HDL) values (2.78 mmol/L) were yielded in T2and T3 had the lowest values (0.61mmol/L) for low density lipoprotein (LDL). For physico-chemical properties, no significant effects (P>0.05) of treatment on pH, colour, cooking loss and tenderness were observed. However, the group treated with A.ferox throughout the production cycle, had the highest pH (6.2), lowest lightness (38.5), highest redness (4.1), highest tenderness (13.86N) and the lowest cooking loss (12.6%). Significant treatment effects (P<0.05) were observed on the composition of the PUFA eicosatrienoic acid (C20:3c8, 11, 14(n-6)) of the breast muscle which was significantly lower in the A. ferox treatment groups than the positive controls. For the thigh muscle, there were significant (P<0.05) treatment effects on composition of palmitoleic acid (C16:1c9) and g-linolenic acid (C18:3c6, 9, 12 (n-3)). No significant (P>0.05) effects were found on oxidative stability of both thigh and breast muscles. In conclusion, the wide use of A. ferox by communal chicken farmers showed its importance as a medicinal plant. Apart from it being an effective medicinal plant, A. ferox inclusion in drinking water results in improved FI, ADG, reduced in LDLC and better g-linolenic and palmitoleic acid composition in the meat.