Irradiation as a Promising Technology to Improve Bacteriological and Physicochemical Quality of Fish.

Fish is an excellent source of protein and other essential minerals and vitamins; nevertheless, several food-borne disease outbreaks have been linked to the consumption of different types of fish. Therefore, we aimed to overcome these health threats by evaluating gamma radiation as a good fish preservation method. The aerobic plate count (APC), identification of most common pathogenic bacteria, organoleptic properties, proximate composition, and other chemical evaluations were detected in both untreated and gamma-treated fish. The overall grades of organoleptic evaluations ranged from good to very good. Fortunately, the overall chemical analysis of all examined fish samples was accepted. For the untreated fish samples, the APC was within and above the permissible limit (5 × 107 CFU/g). Pathogenic bacteria were detected with a high prevalence rate, especially S. aureus, which was found in high percentages among examined untreated fish samples. Regarding the treated fish samples, APC and pathogenic bacterial counts were reduced in a dose-dependent manner, and the irradiation at dose 5 KGy resulted in complete eradication of the aerobic plate count (not detectable) with a mean reduction percentage equal to 100%. However, gamma irradiation has no significant effect on proximate composition; particularly, carbohydrates, proteins, and lipids were not significantly affected by low and medium doses of radiation. Therefore, gamma irradiation is a highly effective fish preservation method without any effect on fish quality. Additionally, gamma irradiation as a cold process is an attractive technology for solving the problem arising from fish-borne pathogens, and it has been purposed in this study as a cheap and safe method for reducing microbial contamination of fish.

Growth, carcass parameters, biochemical and oxidative stress indices, and meat traits of duck breeds under different stocking densities.

This investigation was aimed to inspect if there is an influence of various stocking density on growth, carcass parameters, blood indices, and meat traits of Muscovy and Mallard ducks. One hundred twenty-six 1-day-old of each Muscovy and Mallard ducks were randomly allocated into three experimental groups with different stocking density. Group one (SD1) was 5 ducks/m2, while group 2 (SD2) was 7 ducks/m2 and group 3 (SD3) was 9 ducks/m2. The growth, carcass parameters, meat quality, blood indices were calculated. Body weight of SD1 was 18 and 4.5% heavier than SD2, while, it was 29.5 and 12% heavier than SD3 of Muscovy and Mallard duck breeds, respectively. SD3 possessed the highest levels of, H/L, ALT, AST, LDL, VLDL, and MDA with the lowest levels of lymphocyte, SOD,GSH, GPX, C3, total antioxidant capacity and IGG of both ducks' breeds. The carcass weight decreased by 40 and 15% from SD1 to SD3 in Muscovy and mallard ducks, respectively. The dressing % was highest at SD1 (84 and 83%) when compared with SD3(71and80%) of Muscovy and Mallard ducks, respectively. Cooking loss was 20 and 16% greater in group three when compared with group one in Muscovy and Mallard ducks, respectively. In conclusion ducks raised in low SD possessed the best performance with better welfare.

Anti-Biofilms' Activity of Garlic and Thyme Essential Oils against Salmonella typhimurium.

Biofilm control by essential oil (EO) application has recently increased to preclude biofilm production on foods and environmental surfaces. In this work, the anti-biofilm effects of garlic and thyme essential oils using the minimum inhibitory concentration (MIC) method against Salmonella typhimurium recovered from different abattoir samples were investigated along with the virulence genes (InvA, SdiA and Stn genes), and the antimicrobial susceptibility profile of S. typhimurium as well. The obtained results revealed that S. typhimurium contaminated abattoir samples to varying degrees. The InvA gene was investigated in all isolates, whereas the SdiA and Stn genes were observed in four and three isolates, respectively. Utilizing the disc diffusion method, S. typhimurium isolates demonstrated substantial resistance to most of the examined antibiotics with a high multiple antibiotic resistance index. S. typhimurium isolates demonstrated biofilm formation abilities to various degrees at varied temperatures levels (4 °C and 37 °C). In conclusion, the obtained samples from the research area are regarded as a potential S. typhimurium contamination source. Furthermore, garlic essential oil (GEO) has more potential to inhibit S. typhimurium biofilm at different sub-minimum inhibitory concentrations as compared to thyme essential oil (TEO). Therefore, these EOs are considered as potential natural antibacterial options that could be applied in food industry.

Potential impact of stocking density on growth, carcass traits, indicators of biochemical and oxidative stress and meat quality of different broiler breeds.

The aim of the current study to investigate the potential impact of different stocking densities on growth performance, carcass traits, indicators of biochemical and oxidative stress and meat quality of Arbor Acres and Ross-308 broiler breeds to recommend the better stocking density with low production cost simultaneously with high quality. A total of 312 one-day old of each Arbor Acres broiler and Ross-308 were randomly classified into 3 experimental groups with different stocking density, each of 6 replicates. The first group (SD1) was 14 birds/m2 (28 kg/m2), while the second group (SD2) was 18 birds/m2 (36 kg/m2) and the third group (SD3) was 20 birds/m2 (40 kg/m2). The growth performance, carcass traits, meat quality hematological and biochemical parameters were measured. SD3 group possessed the lowest body weight. Alanine transaminase in Arbor Acres was 15 and 14% higher in SD3 when compared with SD1 and SD2, respectively. While, was 21 and 20% of Ross-308, respectively. SD3 revealed the highest values of cholesterol, TG, MDA, and LDL of both breeds when compared with SD1 and SD2, with the lowest levels of HDL, GPX, and IGG. Birds of SD3 was the nastiest carcass weight 873 (P = 0.000) and 1,411.60 g (P = 0.000); dressing percentage 63.07 (P = 0.000) and 75.83% (P = 0.000); breast weight 513.10 g (P = 0.000) and 885.50g (P = 0.000); thigh weight 359.90 g (P = 0.000) and 526.08 g (P = 0.000) when compared with SD1 and SD2 of Arbor Acres and Ross-308, respectively. The dressing % of SD1 and SD2 was approximately 19% better than that of SD3 of Arbor Acres, while it was 4% of Ross-308. The cooking loss and drip loss of breast and thigh muscles were higher in SD3 of both breeds. Moreover, SD3 possessed the highest bacterial count. In conclusion birds reared in medium stocking density revealed better performance and welfare than high density but similar to low density. Therefore, from the economic point, medium density was the best.

Heavy metal residues in canned fishes in Egypt.

A total of 75 random canned fish samples, 25 each of canned (canned tuna, sardine and mackerel) during 2009, were collected from Zagazig Markets for determination of lead, cadmium, zinc, copper and tin residues using atomic absorption spectrophotometer. The obtained results revealed that the mean values of the lead residues in the examined canned tuna, sardine and mackerel were 0.127 +/- 0.02, 0.013 +/- 0.004 and 0.023 +/- 0.01 (ppm) respectively. The mean concentrations of cadmium residues were 0.022 +/- 0.001, 0.048 +/- 0.003 and 0.027 +/- 0.003 ppm, respectively. While in case of zinc, the residual levels were 1.97 +/- 0.12, 2.369 +/- 0.32 and 1.126 +/- 0.24 ppm, respectively. Copper residual levels in the examined samples were 0.293 +/- 0.08, 0.221 +/- 0.03 and 0.08 +/- 0.02 ppm, respectively. In case of tin, the residual levels were 1.496 +/- 0.30, 1.209 +/- 0.26 and 0.379 +/- 0.11 ppm respectively.