Evaluation of in-field efficacy of dietary ferric tyrosine on performance, intestinal health and meat quality of broiler chickens exposed to natural Campylobacter jejuni challenge

Campylobacter is an important pathogen commonly found in chickens that can cause severe acute gastroenteritis in humans. Despite intensive efforts to inhibit food-borne transmission of Campylobacter no effective strategy exists to reduce Campylobacter loads in farmed broilers. This study examined the capacity of a novel feed additive to lower Campylobacter jejuni populations and to improve growth efficiency of broiler chickens. A total of 384 male one-day-old broiler chicks were used in a 42-day trial. Birds were randomly allocated into four treatments with six replicates of sixteen chicks per pen. Three groups were fed the basal diets further supplemented with TYPLEX™ chelate (ferric tyrosine) at various concentrations (0.02, 0.05 and 0.20 g/kg, groups T2-T4, respectively). Control group (T1) was fed basal diets in mash form that did not contain added ferric tyrosine. Feed and water were provided ad libitum. At 20 days of age, broilers were exposed to natural C. jejuni challenge by introducing contaminated litter from a commercial farm. At day 25, pen litter samples analysed positive for C. jejuni, and the infection intensity was homogeneous among pens. At the end of the study C. jejuni counts in bird caeca were significantly reduced, by 2 log10 in the T4 group, compared to the T1 Control and T3 groups (p = 0.004). During this study, a natural infection with Eimeria tenella occurred at days 26-29. For animal welfare reasons all birds were treated with an anti-coccidial drug as recommended, for two consecutive days. At day 42, diarrhoea was observed on the litter in only 1 of 6 pens in the T4 group, but in 5 of 6 pens in the T1 Control group. In addition, autopsies showed that the T4 group had the highest percentage of birds with normal intestinal tracts. The T1 group had the lowest percentage of birds with infection-free tracts, and higher incidence of coccidiosis and bloody diarrhoea. At 42 days of age all birds were slaughtered and samples collected for further analysis. Birds in the T4 group tended to exhibit improved weight gain and feed efficiency, a result that warrants further investigation. Collectively, our data suggest that addition of ferric tyrosine at 0.20 g/kg exerts a protective effect against C. jejuni and coccidiosis

Safety Issues Regarding the Detection of Antibiotics Residues, Microbial Indicators and Somatic Cell Counts in Ewes’ and Goats’ Milk Reared in Two Different Farming Systems

Milk samples of ewes’ and goats’ unprocessed milk were collected from milk tanks from various farms in Epirus, Greece and classified in two groups according to the type of farming. Analyses of the samples included microbial inhibition assays to detect the presence of antibiotic residues, isolation of Staphylococcus aureus and Escherichia coli strains as microbiological indicators for susceptibility to antimicrobial medicines, Somatic Cells and Coagulase Negative Staphylococci (CNS) counts. These findings were correlated with each other as well as to the stage of the lactation period and to the type of the farming practices. Monitoring of bulk tank milk for residues of antibiotics should be performed after heating of the milk, on a regular basis, and should include at least two different tests. The results point out that the type of farming affects the CNS counts as well as the prevalence of residues in the milk. Furthermore, the inverse correlation between CNS counts and prevalence of residues of antibiotics suggests a possible protective role of CNS. Resistance of the bacterial indicators to antibiotics was random and relatively rare, perhaps acquired in past due to misuse of antibiotics, turning the indicator microorganisms to reservoir of resistance

Identification by MALDI-TOF MS and Antibiotic Resistance of <i>Riemerella anatipestifer</i>, Isolated from a Clinical Case in Commercial Broiler Chickens

The Gram-negative bacterium Riemerella anatipestifer (RA) is known to cause clinical disease with severe economic impacts primarily in ducks and less frequently in geese and turkeys. RA was isolated and identified in broiler chickens, from a clinical case in a commercial broiler farm located in the southwest mainland of Greece. The morbidity and the mortality in the broiler house were estimated at 10% and 5% respectively. The observed clinical signs appeared at the age of 30 to 42 days with respiratory distress (dyspnea), white fluid feces and stunting. Post-mortem examinations displayed serositis, pericarditis, perihepatitis and airsacculitis. Edematous swelling around the tibio-tarsal joints was observed in some birds. Tissue samples from lesions were streaked on selective media. Three bacterial isolates were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Moreover, an antibiogram analysis was performed for the three RA strains, using a pattern of 16 common antibiotics to advocate the most effective drugs for a proper treatment. All the RA isolates were sensitive to ceftiofur, sulphamethoxazole–trimethoprim and amoxicillin, whereas all were resistant to gentamicin, tylosin, tetracyclin, colistin sulphate, spectinomycin, lincomycin and oxytetracycline

Optimization of the Composition of a Novel Bioactive Silage Produced by Mixing of Ground Maize Grains with Olive Mill Waste Waters, Grape Pomace and Feta Cheese Whey

In this work, the production of a novel and sustainable silage was realized and optimized. Three agro-industrial wastes produced in bulk: olive mill wastewater (OMWW), grape pomace (GP) and de-proteinized feta cheese whey (DFCW) were mixed with coarsely ground maize grains, and the mixture was inoculated with commercial lactic bacteria starter culture and fermented for 30 days under anaerobic conditions to obtain silage. Sixty-seven recipes with varying compositions of the three agro-wastes were ensilaged, and four silage quality indices: pH value, % acidity as lactic acid, total lactobacillus count (cfu/g) and total yeast and mold count (cfu/g) were monitored throughout the ensilage process, and the obtained data were used to perform multicriteria optimization of the silage composition. The optimization target was to simultaneously maximize the pH drop, % total acidity as lactic acid and lactobacillus count while minimizing the count of undesirable yeasts and molds. Following this optimization strategy, it was found that the best composition of the mixture of all three tested agro-industrial wastes to obtain a high-quality silage was the one containing: 20% w/w GP, 60% w/w OMWW and 20% w/w feta cheese whey. Finally, the produced silage was tested in broilers’ nutrition and by 10% w/w inclusion in the feed, which led to the production of high added-value bioactive meat rich in ω-3 fatty acids and with high antioxidant capacity

Antimicrobial and Methicillin Resistance Pattern of Potential Mastitis-Inducing <i>Staphylococcus aureus</i> and Coagulase-Negative Staphylococci Isolates from the Mammary Secretion of Dairy Goats

Staphylococcus spp. is an important mastitis-inducing zoonotic pathogen in goats and is associated with antimicrobial resistance (AMR). The objectives of this study were to determine the prevalence and composition of staphylococci in individual mammary secretion (MS) samples of clinically healthy goats and to evaluate the phenotypic AMR pattern and the presence of methicillin resistance in the Staphylococcus spp. strains. Staphylococcus spp. isolates (n = 101) from the MS samples (n = 220) were identified to species level using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The antimicrobial susceptibility testing included a disk diffusion assay and the determination of the minimum inhibitory concentrations (MIC) of resistant strains (n = 46). Presumptive methicillin-resistant strains (n = 9) were assessed for the presence of mecA, mecC and SCCmec/orfx genes. Staphylococcus spp. isolates were recovered from 45.9% of the MS samples, of which, 72.3% was identified as coagulase-negative staphylococci (CoNS), with the remaining being Staphylococcus aureus. CoNS and S. aureus were most commonly resistant to ampicillin (56.2% and 57.1%, respectively), penicillin (26.0% and 39.3%, respectively), amoxicillin (26 % and 25 %, respectively) and cephalexin (12.3% and 25%, respectively) in the disk diffusion method. CoNS exhibited a broader AMR pattern and a higher percentage of resistant strains than S. aureus in the disk diffusion and MIC methods. Of the nine oxacillin- and cefoxitin-resistant strains, three S. aureus and five CoNS strains carried the mecA gene and, thus, were identified as methicillin-resistant. The mecC gene was not found in any of the studied strains. The presence of AMR and methicillin resistance in caprine S. aureus and CoNS poses a concern for animal and public health

Innovative Use of Olive, Winery and Cheese Waste By-Products as Novel Ingredients in Weaned Pigs Nutrition

New sustainable sources of feeds, which can enhance the health and welfare of farm animals, lower feeding costs, and lead to safer products, are of high priority in modern animal production systems. In the present study, a novel silage created from Greek olive, winery, and feta cheese waste by-products, was evaluated as a feed ingredient at different inclusion rates (0%, 5% or 10%) in 34-day-old weaned pigs. The potential beneficial effects on performance, health and intestinal digesta microflora balance of the pigs were evaluated. Additionally, chemical, microbiological and quality analysis of the meat was carried out. Results showed no detrimental effects (p > 0.05) on the pigs’ performance and no significant changes (p > 0.05) in meat pH, color and chemical analysis. Ileum and cecum microflora populations (total anaerobes, Lactobacillaceae) were positively affected (p ≤ 0.05) by the dietary usage of the silage. The microbial populations (Clostridium spp.) of belly meat cuts were positively modified (p ≤ 0.01). The concentration of total phenols in the meat cuts were increased (p ≤ 0.05) and their resistance to oxidation was improved (p ≤ 0.05). In addition, the fatty acid profile of the meat lipids (polyunsaturated and n-3 fatty acids) was positively modified (p ≤ 0.001)

Effects of Dietary Omega-3 Enrichment on the Chemical Composition and the Pathogenic Microbiota of Ovine Milk

The demand for ovine milk and ovine dairy products is constantly increasing due to their exceptional sensorial characteristics and their health benefits for consumers. However, dairy fat content and composition are of particular concern for consumers as well as the medical community, as there are risk factors for coronary disease, diabetes mellitus, cancer, and other serious diseases. For this reason, attempts have been made to control/regulate the fat composition of ovine milk by modifying sheep dietary intake of polyunsaturated fatty acids. In this experimental trial, a group of sheep were fed for 30 days a diet enriched in flaxseeds and lupines, feed ingredients rich in omega-3 fatty acids, aiming to investigate the effects on fat composition and the microbiota of ovine milk. Chemical analysis of the collected milk showed that the omega-3 and omega-6 content was increased. On the opposite, the atherogenic and thrombogenic indexes decreased. Of importance was the semi-protective effect on the udder by the increased omega-3 dietary intake, as depicted by its impact on the biodiversity of the pathogenic microbiota. These findings suggest that ovine milk could be modified under specific conditions to be more appropriate for the consumption by people belonging to high-risk groups for various diseases

Utilization of <i>Tenebrio molitor</i> Larvae Reared with Different Substrates as Feed Ingredients in Growing Pigs

The procurement of adequate feed resources is one of the most important challenges for the animal industry worldwide. While the need for feeds rich in protein is constantly increasing, their production cannot readily keep up. Consequently, to overcome this challenge in a sustainable way, it is necessary to identify and develop new feeding strategies and feed ingredients, such as insect meals. In the present study, Tenebrio molitor larvae that were reared on two different substrates (standard and enriched with medicinal aromatic plant material) were used as feed ingredients for growing pigs. A total of 36 weaned pigs (34 days old) were randomly allocated to three treatment groups and fed either the control diet (A) or diets supplemented at 10% with one of the two insect meals (B and C). At the end of the trial (42 days), blood, feces, and meat samples were collected for analysis. The insect meal supplementation did not affect (p > 0.05) overall performance but significantly modified (p p p p p p > 0.05) meat color or proximate composition. Further research is needed to evaluate the different types and levels of inclusion of insect meals in pig nutrition

Innovative Use of Olive, Winery and Cheese Waste By-Products as Functional Ingredients in Broiler Nutrition

The purpose of this study was to evaluate the dietary use of novel silage that was created by combining three agro-industrial wastes produced in bulk, i.e., olive mill wastewater, grape pomace, and deproteinized feta cheese whey, in the diets of broiler chickens. A total of 216 one-day-old male Ross-308 chicks were randomly allocated to three treatment groups with six replications (12 chicks per pen). Three isocaloric and isonitrogenous diets were formulated to include the examined silage at 0%, 5%, or 10%. Commercial breeding and management procedures were employed throughout the trial. At the end of the trial (day 35), tissue samples were collected for analysis. Feeding 10% silage resulted in increased (p &le; 0.001) final body weight (p &le; 0.001) and feed intake. Jejunum and cecum microflora, as well as breast and thigh meat microflora, were modified (p &le; 0.05) by the dietary inclusion. Thigh meat oxidative stability was improved (p &lt; 0.01) by the silage supplementation. In addition, breast and thigh meat fatty acid profiles were different, respectively, (p &lt; 0.05) in the supplemented treatments compared to the control. The examined silage was successfully tested in broiler diets with potential benefits for their performance and meat quality