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The safety and microbiological properties of chickens reared in free-range production systems (according to the EC Directive 1538/91) were compared with those of chickens reared under conventional systems. Free range chickens belonging to medium growing Isa strain were raised for 70 d with continuous daytime access to open-air area from 28 d to slaughter age and an indoors stocking density not exceeding 27.5 kg/sqm. Conventional chickens belonged to a fast growing hybrid (Ross 708) and were raised for 50 d under intensive conditions. During slaughtering, 20 birds per each group (i.e. FR and C) before and after plucking, after evisceration and after refrigeration (i.e. 5 birds per each step) were randomly collected. On each carcass, the enumeration of Enterobacteriaceae and Campylobacter was assessed. In particular on carcasses of birds collected after refrigeration also the detection of Salmonella was performed. All microbiological determinations were performed using ISO based methods. Moreover, the detection of Salmonella was performed on the neck skin and intestine of 10 additional birds per group by ISO standard methods. On the same intestines the enumeration of Campylobacter was assessed by qPCR. The mean value of Campylobacter counts before (i.e. 6.05 vs 7.04 Log CFU/carcass) and after (i.e. 5.09 vs 6.31 Log CFU/carcass) plucking were significantly lower in free range than conventional birds. The Enterobacteriaceae count showed the same trend but only after plucking (i.e. 6.42 vs 7.03 Log CFU/carcass). In both conventional and free-range systems, positive Salmonella neck skin samples collected before refrigeration were obtained (i.e. 2/5 vs 3/5). However, all carcasses tested after refrigeration but one, belonging to conventional birds, turned out as negative. Similarly, all intestines collected from free-range and conventional chickens were Salmonella negative. Regarding Campylobacter gut enumeration, a lower number of Campylobacter cells were determined on free-range chicken in comparison to conventionally reared chicken (5.0 vs 5.6 Log CFU/g).

There is a growing consumer interest towards poultry products coming from unconventional housing systems with outdoor access. A study was conducted to characterize carcass traits and meat chemico-physical properties of chickens labelled free-range (according to the EC Directive 1538/91) if compared with conventional ones. Free range (FR) female and male chickens were separately raised for 56 and 70 d, respectively, in order to obtain currently marketed product categories (rotisserie and cut-up carcasses). They belonged to medium growing Isa strain and had continuous daytime access to open-air area from 28 d to slaughter age and indoors stocking density did not exceed 27.5 kg/sqm. Conventional (C) female and male chickens belonged to a fast growing hybrid (Ross 708) and were separately raised for 39 and 50 d, respectively, under intensive conditions in a poultry house under controlled environmental conditions at a stocking density of 30-32 kg/sqm. Female and male birds were slaughtered into 2 separate sessions. After slaughtering, 20 carcasses for each group were randomly selected for evaluating carcass cut-up yields and fifteen of them were used to assess quality properties of both breast and leg meat (skin and meat colour, ultimate pH, drip and cooking losses, AK-shear force). C birds had dramatic higher carcass and breast meat yield, whereas FR had higher wing and leg yields (P

The most common ingredients used in poultry marination are sodium chloride and sodium tripolyphosphate. Some few previous studied have been shown that sodium bicarbonate can be profitably used in poultry meat as alternative to phosphates. The aim of this study was to test the effect of different sodium bicarbonate levels (0 to 0.5%) on marination performances and meat quality properties. A total of 210 samples (cylindrical shape of 1×4 cm size) were obtained from an homogenous batch of 24h post mortem broiler breast meat (Cobb 500, females, 46 day-old, 2.48 kg). Samples were subjected to vacuum tumbling with a 12% water:meat ratio using 7 marinating solutions containing the same sodium chloride level (1.0% wt/wt on final product) and increasing concentrations from 0 to 0.5% of sodium bicarbonate (NaHCO3). pH and colour (L*a*b*) before and after marination and subsequent cooking as well as marinade uptake, drip loss, expressible moisture, cooking loss, moisture, yield and texture profile analysis were measured. Meat pH after marination increased with the increasing bicarbonate concentration by estimating an 0.17 pH units increase for 0.10% of bicarbonate addition. The greatest marinade uptake (11.4%) was observed in samples tumbled with 0.30% bicarbonate solution, while higher concentration (0.40 and 0.50%) evidenced significant (P

A study was conducted to compare the microbiological properties of chickens labelled free-range (according to the EC Directive 1538/91) if compared with conventional ones. Free range chickens belonging to medium growing Isa strain were raised for 70 d with continuous daytime access to open-air area from 28 d to slaughter age and an indoors stocking density not exceeding 27.5 kg/sqm. Conventional chickens belonged to a fast growing hybrid (Ross 708) and were raised for 50 d under intensive conditions. During slaughtering, 20 birds per each group before and after plucking, after evisceration and refrigeration (i.e. 5 birds per each step) were randomly collected and used for the quantitative evaluation (i.e. Log CFU/carcass) of total aerobic bacteria, Enterobacteriaceae and Campylobacter. Moreover, the detection of Salmonella was performed on 5 refrigerated carcasses per group as well as on their intestines (also Campylobacter was assessed) and neck skin of 10 additional birds. All microbiological determinations were performed using ISO based methods. Moreover Salmonella was further detected and Campylobacter quantified using traditional and RT-PCR, respectively. The total aerobic and Campylobacter counts before (i.e. 7.88 vs 8.39 and 6.05 vs 7.04 Log CFU/carcass) and after (i.e. 7.29 vs 7.75 and 5.09 vs 6.31 Log CFU/carcass) plucking were significantly lower in free range than conventional birds. The Enterobacteriaceae count showed the same trend but only after plucking (i.e. 6.42 vs 7.03 Log CFU/carcass). In both conventional and free range systems, positive Salmonella neck skin samples collected before refrigeration were obtained (i.e. 2/5 vs 3/5). However, all carcasses tested after refrigeration but one, belonging to conventional birds, turned out as negative.

The sequential feeding is a program which consists of administering diets with different nutrient contents for one ore more days cycles. The aim of this trial was to verify the effect of 24-h cycle sequential feeding on the quality of broiler meat as well as incidence of foot pad dermatitis. A total of 1,320 one-d-old male chicks Cobb 700 were divided in 2 groups of six replicates each. From 1 to 10 d of age all the chickens received the same pre-starter diet (EM 3,060 kcal/kg; CP 226 g/kg). The control group (CON) received for all day long, starter (EM 3,160 kcal/kg; CP 204.8 g/kg), grower (EM 3,220 kcal/kg; CP 191.8 g/kg) and finisher diets (EM 3,240 kcal/kg; CP 183.6 g/kg) respectively from 11-18, 19-38 and 39-44 d. The sequential feeding group (SF) received the same diets of the control for half-day and, for the remaining half, isoenergetic low protein diets (-20%). The breast of SF birds showed a lower pHu (5.76 vs 5.91; P

There is a growing consumer interest towards poultry products coming from unconventional housing systems with outdoor access. A study was conducted to characterize carcass traits and chemico-physical properties of chickens labelled free-range (according to the EC Directive 1538/91) if compared with conventional ones. Free range female (FR-F) and male (FR-M) chickens were separately raised for 56 and 70 d, respectively, in order to obtain currently marketed product categories. They belonged to medium growing Isa strain and had continuous daytime access to open-air area from 28 d to slaughter age and indoors stocking density did not exceed 27.5 kg/sqm. Conventional female (C-F) and male (C-M) chickens belonged to a fast growing hybrid (Ross 708) and were separately raised for 39 and 50 d, respectively, under intensive conditions in a poultry house under controlled environmental conditions at a stocking density of 30-32 kg/sqm. Females (FR-F and C-F) and male (FR-M and C-M) birds were slaughtered into 2 separate sessions. After slaughtering, 20 carcasses for each group (FR-F, 1.2 kg; FR-M, 1.9 kg; C-F, 1.2 kg; C-M, 2.3 kg) were randomly selected for evaluating carcass cut-up yields and fifteen of them were used to assess quality properties of both breast and leg meat (skin and meat colour, ultimate pH, drip and cooking losses, AK-shear force). C birds had dramatic higher carcass and breast meat yield, whereas FR had higher wing and leg yields (P

The study aims to evaluate the effect of different physical forms of hydrolysable tannins from sweet chestnut added to the broiler chicken feed on production performance and incidence of foot pad dermatitis (FPD). A total of 1,540 day old male Ross 708 chicks were split up into 4 groups and fed the same basal diets supplemented with 0 tannin (CON) or with 260 mg/kg feed of tannins either in powder (POW) or coated (COA) or granules (GRA) forms for the whole trial duration (48 d). Body growth rate and feed efficiency were not affected by powder or granule tannin forms, while they were significantly depressed by coated tannin. POW and GRA birds showed a lower incidence of FPD than both CON and COA (8 and 8% vs 21 and 28% respectively, P< 0.01). Litter moisture percentages of groups receiving the tannin supplementation were 3-3.6 points lower than those of the CON group. This trial demonstrated that the supplementation of hydrolysable tannins both in powder and granule forms may represent an interesting strategy to reduce the incidence of FPD and consequently to improve the general welfare status of broiler chickens.

A study was conducted to evaluate the quality traits of turkey breast rolls prepared with fresh or thawed meat according to four product formulations. Turkey rolls (n=12/type of meat/formulation) were prepared by mixing grounded turkey breast meat (fresh or thawed) with a marinating solution prepared with equal amounts and types of water and non-meat ingredients except for one single functional ingredient: i) STPP: sodium tripolyphosphate (control group); ii) YEAST: yeast extract; iii) CARR: carrageenan; iv) COM: commercial mix containing sodium citrate, sodium carbonate, dextrose, and yeast extract. In respect with fresh meat, thawed meat determined higher cooking loss and purge loss as well as higher product firmness (higher AK-shear value, gel strength and Texture Profile Analysis parameters). As for functional ingredients, STPP and COM determined a lower fluid losses assessed by filter paper press method and purge loss as well as a superior product firmness in respect with YEAST and CARR. COM determined a darker colour in respect with STPP, CARR and YEAST (L*: 72.2 vs. 74.8 vs. 76.6 vs. 76.9, respectively; P

Gas plasma treatment of whole egg represents an innovative decontamination technique for the eggshell surface. However, it is not clear if the treatment can damage the natural defence of the egg such as cuticle and shell membranes. Based on previous microbiological tests, 3 batches of 15 extra fresh eggs were treated as follows: gas plasma afterglow for a) 45min or b) 90 min or c) untreated (Control). The plasma emission, produced by a resistive barrier discharge prototype set up by the University of Bologna, was characterized by the presence of very reactive species such as OH and NO radicals. After treatment, the eggs were examined for translucency by hand candling and then empted and rinsed of their content. A 1 cm2 wide strip of eggshell was then carefully removed and subdivided into two smaller sections for assessment of the cuticle and the inner surface of inner shell membrane by SEM (Hitachi 501B, magnification 300×500, 15kV). Our results indicate that there was no significant treatment effects in terms of translucency or in the appearance of the cuticle. The inner surface of the inner shell membrane however displayed a slightly higher incidence of adherent material (albumen) after gas plasma treatment, but this effect could simply be due to ineffective rinsing of the eggshells during the preparation of the samples.

Hot air pasteurisation was investigated in the RESCAPE project as innovative treatment for surface bacterial decontamination of table eggs. Possible side effects of the treatment on egg quality traits were also studied. Each egg was submitted simultaneously to two flows of hot air generated by two electric heathers (above the eggs) and one flow of air at room temperature (below the egg). The selected thermal cycle was characterised by two shots of hot air at 600°C for 8 sec, each shot, with a cooling interval of 32 sec between the two shots. The decontamination power of the selected thermal treatment was evaluated over one month on shell eggs experimentally inoculated with either Salmonella Enteritidis, Escherichia coli, Listeria monocytogenes and on shell eggs containing only the indigenous microflora. The S. Enteritidis load on treated eggs was lower than the positive control until day 21 with a mean of 1,3 log reduction. A similar log reduction of 1,2 log was observed on L. monocytogenes load of eggs immediately after the treatment. No statistically significant results were obtained comparing E. coli on treated and untreated eggs as well as indigenous microflora on treated and untreated eggs. No detrimental effects on quality traits immediately after the treatment as well as after 28 days of storage at 20°C were recorded.

Hot air pasteurisation was investigated in the EU funded project named RESCAPE as innovative treatment for surface bacterial decontamination of table eggs. Possible side effects of the treatment on egg quality traits were also studied. The decontamination power of hot air was evaluated over one month on shell eggs experimentally inoculated with Salmonella Enteritidis, Escherichia coli or Listeria monocytogenes. The S. Enteritidis and L. monocytogenes populations on the surface of treated eggs showed a significant reduction in comparison to untreated ones. No statistically significant results were obtained comparing E. coli loads on treated and untreated eggs. No detrimental effects on quality traits immediately after the treatment as well as after 28 days of storage at 20°C were recorded.

Salmonella is one of the major causes of food borne illnesses in humans. According to the Commission’s report on zoonoses (EFSA, 2005) Salmonellosis represent the second most frequent zoonosis with 176,395 reported human cases Amongst foodstuffs, Salmonella was most often reported from fresh poultry and pig meat where proportions of positive samples up to 18% were detected. In table eggs, findings of positive samples ranged from 0% to 6%, but over the past 5 years an overall decreasing trend in occurrence of Salmonella in eggs was observed. In animal populations, Salmonella was most frequently detected in poultry flocks. In general poultry farms and food related are an important source of human Salmonella infections. Therefore recent European Community legislation foresaw Salmonella reduction for animal population including breeding, laying hens, broiler and turkey flocks. This paper will evaluate the foodborne salmonella prevalence in human in relation to the main foods contaminated by this pathogen. In accordance with the Community legislation on zoonoses aiming at reducing the incidence of food-borne diseases in the European Union (Regulation (EC) No 2160/2003), a European Union-wide baseline survey was carried out to determine the prevalence of Salmonella in breeding flocks of Gallus gallus, laying hens and broilers. The results, recently published by EFSA will be presented in relation to different countries and different type of farms. Moreover national control programmes submitted to the European Commission for its approval, in order to reduce the salmonella dissemination in animal population, will be presented. Measures to reduce Salmonella prevalence in live animals is believed to be one of the most effective ways of reducing the contamination of foodstuffs and the number of human salmonellosis cases. For this reason the direct and indirect prophylaxis measures that can be adopted in poultry farms will be discussed as well as the research studies more promising in order to decrease or eliminate the salmonella contamination in eggs and poultry meat.

The attitude of the yolk to remain separated from the albumen is an important aspect for the shelling process. Eggs can be stored for several months and processed some days after pulling out from the refrigerated cell. In the present research, eggs for food-processing of two genetic types of hens are stored for seven months at 0°C. During this time the parameters describing the strength of the vitelline membrane-yolk system were measured together the main egg quality parameters such as height of the thick albumen, Haugh and yolk indices. Measurements were carried out to assess the effects of different post-refrigeration treatments: eggs were analysed immediately after pulling out from the cell, after 5-6 h, when the temperature of 18°C is reached, and after further seven days at 18°C. Multiple regression statistical models were given to evaluate the influence of the different parameters considered in the study. According to these models, about seven months of storage at 0°C cause a decrease in the maximum force absorbed by the membrane-yolk systems of 10-12% while the permanence of the eggs outside the cell for seven days before processing causes a decrease of 14- 17%. The decrease in maximum force for the eggs after 5-6 h outside the cell is 4-5% if compared with the eggs analysed immediately after refrigeration. About seven months of storage at 0°C cause a decrease in the rupture energy of 14-17% and seven days at 18°C after refrigeration involve a decrease of 5-7%. After seven months of storage at 0°C it was observed a decrease in the Haugh index of 6–8 % only. The differences in force and energy of the membrane-yolk system measured after laying for the two genetic types of hen decrease during storage and post-refrigeration time.

A trial was carried out to evaluate the influence of improved housing conditions for broilers kept on litter on productivity, carcass and meat quality traits. A total of 33,000 Ross 508 female broiler chickens were divided into two groups Welfare (WLF) and Standard (STD) and reared under different stocking density (14 vs. 19 birds/sq m), litter (wood shaving) amount (3.5 vs. 2.5 kg/sq m) and light:dark regimen (18:6 vs. 23:1). Birds were slaughtered at 40 or 50 d of age. Environmental temperature and humidity as well as litter moisture did not change between the two housing conditions. WLF birds reached a higher body weight but had a slight worse feed efficiency, whereas no differences were found in carcass traits. Breast meat quality evaluation showed higher moisture content and poorer water holding capacity in WLF birds.

The measure of the proton nucleus transverse relaxation rate (R2) is a good candidate for evaluating the quality of intact eggs albumen. For its succesful use some physical characteristics it depends on have been evaluated.

A study was conducted to sensory traits of meat from chickens labelled free-range (according to the EC Directive 1538/91) if compared with conventional ones. Free range female and male chickens were separately raised for 56 and 70 d, respectively, in order to obtain currently marketed product categories (rotisserie and cut-up carcasses). They belonged to medium growing Isa strain and had continuous daytime access to open-air area from 28 d to slaughter age. Conventional female and male chickens belonged to a fast growing hybrid (Ross 708) and were separately raised for 39 and 50 d, respectively, under intensive conditions in a poultry house under controlled environmental conditions. After slaughtering, 20 carcasses for each group were randomly selected and used to conduct a triangle test (42 untrained panellists) and consumer test (54 untrained panellists) on both breast and leg meat. Triangle test evidenced that both breast and leg meat from free range birds had sensory properties (P

Marination is a commonly used method of adding value to different types of meat which involves injection and/or tumbling to disperse in a muscle a solution of water, salt and other ingredients. The most common ingredients used for poultry marination are salt and phosphates, which have been shown to increase meat yield and water-holding capacity, as well as improve colour and texture. However some nutritional drawbacks have been recently evidenced in relation with the use of phosphates in foods. Therefore the aim of this study was to test ingredients able to replace phosphates in meat products. A total of 140 samples (cylindrical shape of 1×4 cm size) were obtained from an homogenous batch of 24h post mortem broiler breast meat (Ross 708, females, 47 day-old). Samples were subjected to vacuum tumbling with a 12% water:meat ratio using one of the following seven marinating solutions: non-marinated (control, C); 7.7% NaCl (S); 2.3% Na4O7P2 (P); 2.3% NaHCO3 (B); 7.7% NaCl and 2.3% Na4O7P2 (SP); 7.7% NaCl and 2.3% NaHCO3 (SB); 7.7% NaCl, 2.3% Na4O7P2 and 2.3% NaHCO3 (SBP). pH and colour (L*a*b*) before and after marination and subsequent cooking as well as marinade uptake, drip loss, expressible moisture, cooking loss, moisture and yield were measured. The main results confirmed that independently of the ingredient and marination conditions, the water-binding capacity was improved, cooking loss was reduced, and the yield was enhanced compared with non-marinated meat samples. Sodium bicarbonate was able to guarantee at least the same marination performances in respect to phophates. In conclusion, this study showed that sodium bicarbonate in combination with salt can be profitably used also in poultry meat as alternative to phosphates to prepare further processed products.

The effect of organic selenium feed supplements on the activities of antioxidant enzymes and on lipid peroxidation was investigated in the chicken heart muscle during fattening. The experiment was carried out on Ross 308 broiler chickens of both sexes, either on standard diet (control group, n = 30) or receiving organic selenium supplementation (Sel-Plex , Alltech) in the standard diet (experimental group, n = 30). After two, four and six weeks of fattening, 10 chickens from the control group and 10 chickens from the experimental group were sacrificed. In the heart muscles of the birds from both groups, the activities of glutathione peroxidase (GSH-Px), catalase (CAT), cooper zinc superoxide dismutase (Cu, Zn-SOD), manganese superoxide dismutase (Mn-SOD), reduced glutathione (GSH) and lipid peroxide (TBARS) were determined. After the fourth week of age, the chickens that had been given organic selenium supplementation displayed a significantly higher activity of GSH-Px (P0.05). During fattening, age-related differences of antioxidant enzymatic activities and GSH and TBARS concentrations were obtained in the control and in the experimental group. After four weeks of age, a significant increase in GSH-Px (P

Campylobacteriosis represent an important public health problem in Croatia, especially in children. Broilers are primarily colonized with C. jejuni, less often with C. coli and rarely with other species (Newel and Wagenaar, 2000). Poultry meat is a major source of campylobacteriosis and flock prevalence varies between EU countries, ranging from 5% to more than 90% (EU, 2003). Previous investigations regarding Campylobacter spp. in poultry in Croatia performed on feces of different poultry species revealed 11.69 % positive broiler samples (Krstulović et al., 2003). This investigation was conducted on selective media, and recently modern molecular diagnostic methods weren’ t used. To detect the prevalence of Campylobacter spp. in the northern part of Croatia, where the most of the broiler farms are located, cloacal swabs were randomly taken from 91 broiler chickens of different ages situated at three different farms. After pre-enrichment, cultures was streaked on modified charcoal cefoperazone desoxycholate agar (mCCDA) plates and incubated for 48 hours at 42&ordm ; C, in microaerobic atmosphere. All suspected colonies were presumptively identified as Campylobacter on the basis of macroscopic and microscopic appearance of colonies and positive catalase and oxidase reaction. The DNA was extracted from a 48 h cultures prepared in Nutrient Broth No. 2 as described by Jackson et al. (1993). The identification of strains was obtained by the multiplex PCR (mPCR) as described by Manfreda et al. (2003). The expected PCR amplicons were at 857, 589 and 462 by corresponding to the genus Campylobacter and to the species C. coli and C. jejuni, respectively. Altogether 35 (38.46%) samples were positive, whereas 18 (51.42%) of them were detected as C. coli and 17 (48.58%) as C. jejuni. Further investigation will be conducted on larger number of chickens to reveal the real prevalence of both Campylobacter strains. The mPCR, for the first time used in our laboratory, based on the use of different sets of primers is simple and time-saving method, can be performed for the simultaneous identification of different Campylobacter species and could contribute to the interpretation of results of epidemiological studies and determine whether particular Campylobacter types persist along the food chain or establish themselves as house flora in farms and slaughterhouses, what will be the goal of future investigations.

The aim of this study was to investigate the effect of the organic selenium supplementation and fasting on lipid concentrations and lipoprotein lipase activity in adipose tissue of Ross 308 broiler chickens. Chickens were divided into two groups: first group were fed with standard diet (control group) and second were fed the same diet supplemented with organic selenium (Sel-Plex group). Adipose tissue samples were collected at the age of 42 days and after 48-hours food deprivation and triacylglycerol, total and free cholesterol concentrations and lipoprotein lipase activity were assayed. Adipose tissue total cholesterol concentration in the chickens fed with organic selenium supplementation was significantly lower (P0.05). Present research suggests that organic selenium supplementation influences cholesterol metabolism in adipose tissue by decreasing total cholesterol concentration during the fattening period and increasing free cholesterol concentration after 48-hour food deprivation.