Heat stress causes economic losses via decreasing feed intake, nutrient digestion, weight gain, feed conversion, immunity, carcass quality and increasing mortality in broilers. The aim of the study was to assess the ability of dietary additive combinations to ameliorate the detrimental effect caused by chronic heat stress (32 ± 2ºC for 24 h per d) on performance, carcass traits, metabolic status and economic efficiency of broiler chickens. A total of 420, one-day old Cobb-500 broiler chicks were assigned into seven treatment groups (n=60) of five replicates. Each replicate contained 12 unsexed chicks. The control groups did not receive any supplementation to the basal diet (thermoneutral control (TNC) and heat stress control (HSC) groups). The other groups received control diet supplemented with 1 % cumin plus 1 % turmeric powders (T1); 1.5 g/kg potassium chloride plus 2 g/kg sodium bicarbonate (T2); 1000 ppm propolis plus 15000 IU vitamin A (T3); 1200 ppb chromium plus 500 ppm vitamin C (T4) ; 1200 ppm betaine plus 500 ppm vitamin E (T5). The results indicated that at 42 d of age, all dietary additive combinations improved the growth performance indices, carcass traits, concentrations of serum antioxidant enzyme biomarkers, stress biomarkers and economic efficiency in comparison to HSC group. Based on the obtained results, it could be concluded that dietary supplementation with betaine and vitamin E followed by chromium and vitamin C combinations offers a good management practice for alleviating heat stress related depression in the performance of broiler chickens.

A B S T R A C TA total of 120 random samples of fully and half cooked chicken meat products (60 of each) were collected from different supermarkets at El-Dakahlyia , El-Kalyobia and El-Gharbia governorates for isolation of Salmonellae and detection of their antimicrobial sensitivity. The obtained results indicated that Salmonellae were isolated from the examined samples of chicken nuggets , chicken hot wings, chicken shawerma (half cooked), chicken luncheon ,chicken frankfurter and chicken shawerma (fully cooked) with percentages of 25%, 25%, 30%, 0%, 15% and 35%, respectively. Moreover, the isolated Salmonellae could be serologically identified as S. typhimurium, S. anatum, S. enteritidis, S. kentucky, S. muenster and S. virchow. Moreover, Salmonellae appeared resistant to Nalidixic acid (100%). In contrast, Gentamycin had the basic effect on viability of Salmonellae followed by Kanamycin and Norfloxacin.

The growth kinetics of Salmonella Enteritidis in raw beef has been little studied so far. Thus, this study aimed to clarify the growth kinetics of the pathogen in ground beef using a growth model. When Salmonella cells inoculated at various initial doses into ground beef were incubated at a given temperature (24℃), the maximum population (Nmax) of the microbe at the stationary phase varied with the doses. This relationship was expressed with a polynomialequation for Nmax using the initial dose. The combination of the growth model and the polynomial equation successfully predicted Salmonella growth at a given initial dose. When Salmonella cells inoculated in ground beef were incubated at various constant temperatures, the growth curves of the pathogen and natural microflora (NM) were well described with the growth model. The rate constant of growth and the Nmax values for Salmonella and NM were then analyzed kinetically. From these results, growth curves of Salmonella and NM in ground beef stored at dynamic temperatures were successfully predicted. Competition between Salmonella and NM in ground beef was also found during the storage. This study could give usable information on the growth of Salmonella and NM in ground beef at various temperatures.

Recently we clarified the growth kinetics of Salmonella Enteritidis in raw ground beef at various temperatures with our growth model. Based on those results, this study aimed to build a new methodology to predict the growth of Salmonella in ground beef at given initial concentrations of the pathogen and temperatures. Namely, the maximum cell population of Salmonella at various combinations of its initial concentration and temperature was developed with a polynomial equation. The rate constants of Salmonella growth at various temperatures were estimated with the square root model studied in our recent study. A new system consisting of our growth model, the polynomial equation, and the square root model successfully predicted the growth of Salmonella inoculated at given concentrations in beef at constant and dynamic temperatures. The growth of natural microflora in beef at those temperature patterns were also successfully predicted with the growth model.

This study was conducted to confirm the bacterial conditions of fish products with E.O.S, and their hazards on public health. A total of 60 samples of fish products represented by smoked: herring and smoked salmon-semi cooked: fish finger and breaded shrimp (15 of each) were collected from different retail markets for bacteriological examination. The average of APC, Coliform, Escherichia coli, Mould & yeast and Staphylococcus aureus counts (log 10 cfu/g) were 4.