Effect of Mycoplasma synoviae strains isolated from the respiratory and reproductive tracts of chicken on SPF chicken embryos

Mycoplasma synoviae (MS) infections in poultry are an important epidemiological and economic problem in poultry production all over the world. The differences between M. synoviae strains are related to the pathogenicity and the course of the disease. In recent years, the pathogenicity of M. synoviae strains has increased, and some of them are capable of causing serious infections. Both horizontal and vertical transmission routes play an important role in MS infection in flocks. The aim of the study was to determine the impact of infection with selected MS strains obtained from chickens showing a clinical form of MS infection on SPF chicken embryos. Ten strains of M. synoviae were used for this purpose. The strains were isolated from the respiratory tract and the oviduct of chickens with symptoms typical of infection with this pathogen. Genetic material isolated from liquid cultures of these strains was confirmed by molecular (PCR and LAMP) and microbiological methods. The selected M. synoviae strains belonged to six different genotypes. Significant differences in virulence between the strains were demonstrated. In nine infected groups of embryos, M. synoviae strains caused weight loss, and in seven groups they produced anatomopathological changes characteristic of mycoplasma infections. The most pathogenic for SPF chicken embryos turned out to be strains characterized as genotype F isolated from the chicken oviduct and strains of genotype C isolated from the respiratory tract. One strain of genotype H isolated from the respiratory tract showed no pathogenic effect on SPF chicken embryos. The study showed that infections with M. synoviae can have a significant impact on the production of chicken chicks in commercial hatcheries and the economy of the poultry industry.

Adult Alphitobius diaperinus Microbial Community during Broiler Production and in Spent Litter after Stockpiling

The facilities used to raise broiler chickens are often infested with litter beetles (lesser mealworm, Alphitobius diaperinus). These beetles have been studied for their carriage of pathogenic microbes; however, a more comprehensive microbiome study on these arthropods is lacking. This study investigated their microbial community in a longitudinal study throughout 2.5 years of poultry production and after the spent litter, containing the mealworms, was piled in pastureland for use as fertilizer. The mean most abundant phyla harbored by the beetles in house were the Proteobacteria (39.8%), then Firmicutes (30.8%), Actinobacteria (21.1%), Tenericutes (5.1%), and Bacteroidetes (1.6%). The community showed a modest decrease in Firmicutes and increase in Proteobacteria over successive flock rotations. The beetles were relocated within the spent litter to pastureland, where they were found at least 19 weeks later. Over time in the pastureland, their microbial profile underwent a large decrease in the percent of Firmicutes (20.5%). The lesser mealworm showed an ability to survive long-term in the open environment within the spent litter, where their microbiome should be further assessed to both reduce the risk of transferring harmful bacteria, as well as to enhance their contribution when the litter is used as a fertilizer.

Inhibition of AI-2 Quorum Sensing and Biofilm Formation in Campylobacter jejuni by Decanoic and Lauric Acids

Campylobacter jejuni is a major bacterial cause of human diarrheal diseases worldwide. Despite its sensitivity to environmental stresses, C. jejuni ubiquitously distributes throughout poultry production chains. Biofilm formation mediated by quorum sensing is suggested to be critical to the survival of C. jejuni in agroecosystem. C. jejuni possesses LuxS, the enzyme involved in the production of autoinducer-2 (AI-2) signaling molecules. In this study, two fatty acids, namely decanoic acid and lauric acid, were identified to be effective in inhibiting AI-2 activity of C. jejuni. Both decanoic acid and lauric acid at 100 ppm inhibited ∼90% AI-2 activity (P < 0.05) of C. jejuni without bacterial inactivation. The biofilm biomass of two C. jejuni strains was reduced by 10–50% (P < 0.05) after treatment by both fatty acids, while increased biofilm formation was observed for one C. jejuni strain. In addition, both fatty acids effectively reduced the motility of all tested C. jejuni strains. These findings can aid in developing alternative C. jejuni control strategies in agri-food and clinical settings.

Determinants of Rural Households’ Poultry Chicken Breeds Choice in Wolaita, Ethiopia

To achieve increased productivity in poultry chicken, households’ choice of poultry chicken breeds should be maintained according to their desirability. This study aimed at identifying determinants of rural households’ choice of poultry chicken breeds keeping in Wolaita, Ethiopia. Multistage sampling techniques were used. First, Damot Pulasa district was selected purposively because of high poultry production potential, and then simple random sampling technique was used to select five kebeles and at third stage systematic random sampling was used to select 160 rural households. Data were collected through interview schedule and analyzed using descriptive statistics and econometric regression. Result showed that 54.37% of households owned indigenous poultry chicken breed, 38% owned exotic poultry chicken breeds and 7.63% owned both indigenous and exotic poultry chicken breeds. Households attached socioeconomic, demographic and institutional factors and breed related traits to their poultry chicken breed choices. Indigenous chicken breeds were preferred in mothering ability, disease resistance, scavenging ability; taste of meat and egg traits whereas exotic poultry chicken breeds were preferred for growth rate, productivity and total eggs laid per chicken per year. In addition, Multinomial Logit model result indicated that age and education level of household head determined poultry chicken breed choice. To be effective and efficient any poultry chicken breed promotion effort in the future should consider these particular preferences of households.

Embryonic Thermal Manipulation and in ovo Gamma-Aminobutyric Acid Supplementation Regulating the Chick Weight and Stress-Related Genes at Hatch

Chickens are exposed to numerous types of stress from hatching to shipping, influencing poultry production. Embryonic manipulation may develop resistance against several stressors. This study investigates the effects of thermoneutral temperature (T0; 37.8°C) with no injection (N0) (T0N0), T0 with 0.6 ml of 10% in ovo gamma-aminobutyric acid (GABA) supplementation (N1) at 17.5th embryonic day (ED) (T0N1), thermal manipulation (T1) at 39.6°C from the 10th to 18th ED (6 h/day) with N0 (T1N0), and T1 with N1 (T1N1) on hatchability parameters and hepatic expression of stress-related genes in day-old Arbor Acres chicks. The parameters determined were hatchability, body weight (BW), organ weight, hepatic malondialdehyde (MDA), and antioxidant-related gene expression. Percent hatchability was calculated on a fertile egg basis. Growth performance was analyzed using each chick as an experimental unit. Eight birds per group were used for organ weight. Two-way ANOVA was used taking temperature and GABA as the main effect for growth performance and gene expression studies. Analysis was performed using an IBM SPSS statistics software package 25.0 (IBM software, Chicago, IL, USA). Hatchability was similar in all the groups and was slightly lower in the T1N1. Higher BW was recorded in both T1 and N1. Intestinal weight and MDA were higher in T0N1 against T0N0 and T1N1, respectively. The expression of HSP70, HSP90, NOX1, and NOX4 genes was higher and SOD and CAT genes were lower in the T1 group. The present results show that T1 and N1 independently improve the BW of broiler chicks at hatch, but T1 strongly regulates stress-related gene expression and suggests that both T1 and N1 during incubation can improve performance and alleviate stress after hatch.

Application of Bacteriophages to Limit Campylobacter in Poultry Production

Campylobacter is a major foodborne pathogen with over a million United States cases a year and is typically acquired through the consumption of poultry products. The common occurrence of Campylobacter as a member of the poultry gastrointestinal tract microbial community remains a challenge for optimizing intervention strategies. Simultaneously, increasing demand for antibiotic-free products has led to the development of several alternative control measures both at the farm and in processing operations. Bacteriophages administered to reduce foodborne pathogens are one of the alternatives that have received renewed interest. Campylobacter phages have been isolated from both conventionally and organically raised poultry. Isolated and cultivated Campylobacter bacteriophages have been used as an intervention in live birds to target colonized Campylobacter in the gastrointestinal tract. Application of Campylobacter phages to poultry carcasses has also been explored as a strategy to reduce Campylobacter levels during poultry processing. This review will focus on the biology and ecology of Campylobacter bacteriophages in poultry production followed by discussion on current and potential applications as an intervention strategy to reduce Campylobacter occurrence in poultry production.

Performance of distinct microbial based solutions in a Campylobacter infection challenge model in poultry

Background Antibiotic growth promoters (AGPs) are commonly used within poultry production to improve feed conversion, bird growth, and reduce morbidity and mortality from clinical and subclinical diseases. Due to the association between AGP usage and rising antimicrobial resistance, the industry has explored new strategies including the use of probiotics and other microbial-based interventions to promote the development of a healthy microbiome in birds and mitigate against infections associated with food safety and food security. While previous studies have largely focused on the ability of probiotics to protect against Clostridium perfringens and Salmonella enterica, much less is known concerning their impact on Campylobacter jejuni, a near commensal of the chicken gut microbiome that nevertheless is a major cause of food poisoning in humans. Results Here we compare the efficacy of four microbial interventions (two single strain probiotics, the bacterium—Pediococcus acidilactici, and the yeast—Saccharomyces cerevisiae boulardii; and two complex, competitive exclusion, consortia—Aviguard and CEL) to bacitracin, a commonly used AGP, to modulate chicken gut microbiota and subsequently impact C. jejuni infection in poultry. Cecal samples were harvested at 30- and 39-days post hatch to assess Campylobacter burden and examine their impact on the gut microbiota. While the different treatments did not significantly decrease C. jejuni burden relative to the untreated controls, both complex consortia resulted in significant decreases relative to treatment with bacitracin. Analysis of 16S rDNA profiles revealed a distinct microbial signature associated with each microbial intervention. For example, treatment with Aviguard and CEL increased the relative abundance of Bacteroidaceae and Rikenellaceae respectively. Furthermore, Aviguard promoted a less complex microbial community compared to other treatments. Conclusions Depending upon the individual needs of the producer, our results illustrate the potential of each microbial interventions to serve flock-specific requirements.

Antimicrobial usage in cattle and poultry production in Dar es Salaam, Tanzania: pattern and quantity

Background Antimicrobials are extensively used in cattle and poultry production in Tanzania. However, there is dearth of information on its quantitative use. A questionnaire-based cross-sectional study was conducted from August to September 2019 in randomly selected poultry and small-scale dairy farms, in three districts of Dar es Salaam City eastern, Tanzania, to assess the practice and quantify antimicrobial use. Descriptive and statistical analyses were performed at a confidence interval of 95%. The ratio of Used Daily Dose (UDD) and Defined Daily Dose (DDD) were used to determine whether the antimicrobial was overdosed or under dosed. Results A total of 51 poultry and 65 small-scale dairy farms were involved in the study. The route of antimicrobial administration was 98% orally via drinking water and 2% in feeds for poultry and for small-scale dairy farms, all through parenteral route. Seventeen types of antimicrobials comprising seven classes were recorded in poultry farms while nine belonging to six classes in the small dairy farms. Majority of the farms (poultry, 87.7% and small scale dairy, 84.3%) used antimicrobials for therapeutic purposes. About 41% of the poultry and one third (34%) of the dairy farmers’ were not compliant to the drug withdrawal periods. Beta-lactams, fluoroquinolones, sulphonamides, tetracyclines and macrolides were the commonly used antimicrobials on these farms. In the poultry farms both those with records and those which relied on recall, antimicrobials were overdosed whereas in the small dairy farms, sulfadimidine, oxytetracycline and neomycin were within the appropriate dosing range (0.8–1.2). The majority (58.6%) of farmers had adequate level of practices (favorable) regarding antimicrobial use in cattle and poultry production. This was associated with the age and level of education of the cattle and poultry farmers. Conclusion The study revealed a widespread misuse of antimicrobials of different types and classes in both poultry and small-scale dairy farming in Dar es Salaam, Tanzania. This result gives insight into the antimicrobial use practices and its quantification. The information obtained can guide and promote prudent use of antimicrobials among the farmers by developing mitigate strategies that reduce antimicrobial resistance risk potentials.

Non-Antibiotics Strategies to Control Salmonella Infection in Poultry

Salmonella spp. is a facultative intracellular pathogen causing localized or systemic infections, involving economic and public health significance, and remains the leading pathogen of food safety concern worldwide, with poultry being the primary transmission vector. Antibiotics have been the main strategy for Salmonella control for many years, which has allowed producers to improve the growth and health of food-producing animals. However, the utilization of antibiotics has been reconsidered since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can quickly increase within microbial communities. The use of alternatives to antibiotics has been recommended and successfully applied in many countries, leading to the core aim of this review, focused on (1) describing the importance of Salmonella infection in poultry and the effects associated with the use of antibiotics for disease control; (2) discussing the use of feeding-based (prebiotics, probiotics, bacterial subproducts, phytobiotics) and non-feeding-based (bacteriophages, in ovo injection, vaccines) strategies in poultry production for Salmonella control; and (3) exploring the use of complementary strategies, highlighting those based on -omics tools, to assess the effects of using the available antibiotic-free alternatives and their role in lowering dependency on the existing antimicrobial substances to manage bacterial infections in poultry effectively.