SUMMARY
One hundred sheep carcasses were inspected at Qena abattoirs for determination of yellow colored carcasses. From the inspected carcasses 27(27%) were attained yellow coloration and could be differentiated into 18(66.6%) physiological and 9(33.3) pathological yellow colored carcasses. A total of 216 samples consisted of 144 from physiological and 72 from pathological yellow colored carcasses were collected from 8 different sites; peri-nephric fat (P.F.), liver tissue (L.T.), hepatic lymph node (H.Ln.), gall- bladder (GB), biceps muscle (M1), gastrocnemius (M2), prescapular lymph node (Ln1) and prefemoral (Ln2). All samples were examined for aerobic plate count (APC), psychrophilic count (PC) and enterobacteriacae count (EC), as well as, for incidence of some specific microorganisms (E. coli, Salmonella and coagulase Staph. aureus).
Higher incidence of some specific bacteria were detected in the examined samples of pathological yellow carcasses than that obtained from physiological ones. Therefore, E. coli, Salmonella and Cp- Staph. aureus were detected in percentages of (56.9% and 29.3%), (9.7% and 3.1% ) and (16.6% and 0.0%) from all examined samples of both pathological and physiological yellow carcasses, respectively. Wide occurrence of these bacteria were found in the samples of gall bladder G.B. (77% and 16.6%), peri- nephric fat P.F.(66.6 and 33.3%) and hepatic lymh nodes H.Ln.(55.5; 22.2) of the pathological and physiological yellow carcasses, respectively.
Pathological yellow colored carcasses were heavily contaminated with bacteria than physiological ones. The averages of APC were (2.6x105 ±1.1x103 and 1.7x105 ±0.6x104), PC (5.3x103±0.8x102 and 2.5x103 ±0.7x103) and EC (4.9x104 ±0.3x104 and 3.9x103 ±0.9x102) in all examined samples of pathological and physiological yellow colored carcasses, respectively. Higher APC was obtained in liver tissues (L.T.; 4.6x105 ±0.9x104) of pathological yellow colored sheep carcasses and in hepatic lymph nodes (H.Ln.; 2.7x105 ±0.8x104) in physiological ones. PC was greater in the samples of prefemoral lymph nodes (Ln2; 7.3x103±0.6x103) of pathological yellow carcasses and in prescapular lymph nodes (Ln1; 8.6x103 ±0.5x103) of physiological ones. EC was higher in the samples of gastrocnemius muscles (M2; 8.0x104 ±0.4x103) of pathological yellow carcasses and in peri-nephric fat (P.F.; 7.6x103 ±0.3x103) of physiological ones.
The importance of distinguishing between physiological and pathological yellow coloration in sheep carcasses, as well as, public health hazards resulting from consumption of icteric meat were fully discussed.