Effectiveness of poultry litter amendments on bacterial survival and Eimeria oocyst sporulation

Composting: A biosecurity measure to maximize the benefit of broilers̕ litter

Objective

This study was conducted to evaluate the effect of composting on the count of Salmonella spp., Clostridium perfringens, and New Castle virus (NDV) isolated from broilers' litter. Moreover, to verify the impact of compost thermal stress on the expression of thermal genes harbored in the isolated bacteria.

Materials and Methods

The prevalence of enteric aerobic and anaerobic infections by Salmonella spp., C. perfringens, and viral infections by NDV were investigated in litter samples collected from 100 broiler flocks by conventional methods and polymerase chain reaction.

Results

The samples were positive for Salmonella spp., C. perfringens, and NDV, with prevalence rates of 60%, 55%, and 30%, respectively. An experiment to study the effect of compost on the microbiological quality of litter was applied using five compost heaps with an initial average count of Salmonella typhimurium (3.2 × 105CFU CFU/gm), C. perfringens (6.4 × 105 CFU/gm), and an average titer NDV (105.5 embryo infectious dose50/gm). The microbiological count of heaps after 15 days of composting revealed a reduction in the count of S. typhimurium and C. perfringens by 4 log10 CFU/gm and 3 log10 CFU/gm, respectively. Moreover, the hemagglutinating test revealed no detection of NDV after 15 days of composting. A high degree of downregulation of expression of the thermal genes, dnaK in S. typhimurium isolates and cpe gene in C. perfringens isolates, was detected by quantitative reverse transcription PCR.

Conclusion

The reduction of pathogen counts, the simplicity, and the low cost associated with composting for only 15 days advocate the recommendation for raising awareness of composting as a routine biosecurity measure to prevent the spreading of infection and promote its safe use in agribusiness.

Eichhornia crassipes from wastes to valuable products in water purification and influence on growth and impregnability in overwhelmed broiler chickens

Background

The implementation of green technologies is continually gaining attention worldwide and was considered for removing water pollutants and treating municipal water before its disposal.

Aim

Evaluation of the laboratory antimicrobial actions and chelating activities, and the field influence of Eichhornia crassipes on performance, biochemical and immunoglobulin concentrations, and intestinal microbiota in overwhelmed broiler chickens.

Methods

We assessed the laboratory antimicrobial actions of E. crassipes 1% suspension against bacterial (Escherichia coli O157: H7 and Salmonella Typhimurium) and fungal (Aspergillus niger and Candida albicans) microorganisms using a 96-well minimal inhibitory concentration, and the chelating activities of E. crassipes against calcium sulfate and copper sulfate. Also, we designed randomly four equal groups out of 200 1-day-old Ross^® 308 chicks on a deep litter system. Three groups (G1, G2, and G3) were supplied daily with E. crassipes suspension of 1% from the third day until the end of the experiment, while the fourth group (G4) received non-treated tap water. Broilers of G1-3 were challenged with calcium sulfate (75 mg.l^-1), copper sulfate (200 mg.l^-1), and S. Typhimurium (1.5 × 10⁶ CFU.ml^-1) polluted water respectively on the 7th, 14th, 21st, 28th, 35th days of age. We collected 1,914 samples by the end of the study, these samples included 90 E. crassipes pollutants and 480 E. crassipes microbial mixes, 192 sera, 192 intestinal swabs, and 960 tissues.

Results

Eichhornia crassipes treated water reveals highly significant (p < 0.01) improvements in water quality assessments and a highly significant (p < 0.01) increase in dissolved oxygen levels compared to tap water. Eichhornia crassipes 1% achieved a 100% adsorption capability for calcium and copper sulfate after 1-hour and 100% bactericidal (E. coli O157: H7 and S. Typhimurium) and fungicidal (A. niger and C. albicans) actions after 1, 2, 2, and 2-hours, respectively. Broilers treated with 1% E. crassipes revealed highly significant (p < 0.01) improvements in performance indices, carcasses characteristics, biochemical and immunological parameters, and highly significant (p < 0.01) decreases of cortisol hormone and bacteriological parameters in all treated broiler groups compared to the control.

Conclusion

Eichhornia crassipes 1% reveals a significant improvement in drinking water quality, as well as produces high adsorptive and antimicrobial actions. Eichhornia crassipes 1% improved performance traits, carcass quality, and intestinal microbiota in overwhelmed broilers.

Processing of nuisance animal waste into agricultural products

A technological solution was developed to process slaughter waste and farm manure and transform them into organic and mineral fertilizers. It has been shown that the formation of an enclosure on a goose farm from nitrogen-binding substances (brown coal, a mixture of brown coal with magnesite, used ash substrate) has a positive effect on reducing nitrogen emissions, even to about 80%. The presented solution is in line with ecological trends and ensures comprehensive management of agri-food waste. It reduces the loss of valuable nutrients from renewable sources, increases the efficiency of fertilizers and reduces the environmental nuisance of poultry farms. Organic-mineral fertilizers made from slaughterhouse waste and poultry manure were as effective as expensive commercial mineral fertilizers. New fertilizers helped to obtain a yield similar to the groups fertilized with mineral fertilizers: 11 t per ha for maize (grain), 0.8 t per ha for mustard (seed), 10 kg per 1 m² of radish (all), and 18.5 kg per 1 m² of beet (whole) while reducing production costs thanks to the use of waste materials.

An alternative approach for controlling bacterial pathogens in liquid and solid poultry waste using Calcium hypochlorite Ca(OCl)2 disinfectant-based silver nanoparticles

Inappropriate handling of poultry waste from the beginning to the end of the production cycle could lead to health and environmental hazards. The purpose of this study was to assess the current state of poultry waste management practices as well as to evaluate the efficacy of disinfectants (VIRKON S, Quaternary ammonium compound (QAC), Calcium hypochlorite [Ca(OCl)₂], and nanomaterials (nano-silver particles (Ag NPs), and Ca(OCl)₂-Ag NPs composite) on pathogenic bacteria for use in the disinfection of waste collection areas within poultry operation systems. Two hundred and ten samples were gathered from variant waste types for isolation and identification of pathogenic bacteria. Then, the efficacy of some disinfectants against fifty strains of isolated bacteria was evaluated using a broth micro-dilution assay. Results showed the most predominant bacterial isolates from wastes were E. coli (33.69%), Salmonella spp. (26.09%), followed by K. pneumonae (15.22%) and L. monocytogenes (14.13%). Ca(OCl)₂-Ag NPs had a microbial lethal effect against all pathogenic bacteria (100%) that were isolated from liquid and solid waste. In conclusion, poultry manure waste is collected and dumped on the agricultural land around those chicken farms without any treatment. The Ca(OCl)₂-Ag NPs composite was lethal to all pathogenic microbes isolated from waste and their collected areas at 1.0 mg/L concentration.

The influence of nutrition on intestinal disease with emphasis on coccidiosis

Ever since the poultry industry began to intensify early last century, coccidiosis has been a significant problem with which it has had to contend. Losses due to mortality and morbidity can be significant and before the advent of control agents there were several practices, some of which were nutritional, which were implemented to limit these losses. The development of coccidiostats reduced these problems considerably and as a result some of the more extreme intervention measures were no longer necessary. Modern day interpretation of what may have been happening with some of these early interventions provide interesting insights into what may be possible today should cocciodiostats be removed. More recent research has also indicated that the diet has a significant influence on the ability of poultry to resist and resolve an infection through direct and indirect effects on the pathogen, the immune system and on the litter. This paper reviews the role of dietary ingredients and nutrients on the pathogen to establish and the host to resist such an infection. There is clearly no panacea, but the combination of a few practices may reduce the overall challenge experienced by the poultry producer.

Reducing ammonia emission by aluminum sulfate addition in litter and its influence on productive, reproductive, and physiological parameters of dual-purpose breeding hens

This research investigated the impact of aluminum sulfate (AS) as amendment to different types of litter (new, reused, and mixed litters) for reducing ammonia emission and improving productive performance of local dual-purpose breeding hens. A total of 450 hens and 60 cocks from the Inshas strain were randomly assigned to six groups (five replicates each of 15 hens + 2 cocks) raised in pen floor furnished with a wheat straw litter. The groups included: (1) new, (2) reused, (3) mixed (50% new + 50% reused) litter; the other groups (4, 5 and 6) were respectively housed on the same litter as groups 1, 2 and 3 but with the addition of 495 g of AS/m² litter. The feed conversion ratio was better for layers raised on new litter with or without AS than other groups. Different kinds of litter had different moisture (p < 0.05) and pH (p < 0.05) values. Birds raised on litter types treated with AS significantly (p < 0.05) decreased intestinal pH and decreased total bacterial count compared to the same litter types without AS at the end of the experiment. Birds raised on new litter supplemented with AS had the highest plasma T3, total protein, globulin, Hgb, and PCV% and the lowest levels of uric acid and cholesterol at the end of the experimental period. Therefore, litter amendment with AS, also the mixed or reused one, could be recommended to reduce ammonia and, in turn, increasing plasma T3 and decreasing total bacterial count, leading to increasing bird's performance.

Survival of Escherichia coli in Airborne and Settled Poultry Litter Particles

Airborne Escherichia coli (E. coli) in the poultry environment can migrate inside and outside houses through air movement. The airborne E. coli, after settling on surfaces, could be re-aerosolized or picked up by vectors (e.g., caretakers, rodents, transport trucks) for further transmission. To assess the impacts of airborne E. coli transmission among poultry farms, understanding the survivability of the bacteria is necessary. The objective of this study is to determine the survivability of airborne E. coli, settled E. coli, and E. coli in poultry litter under laboratory environmental conditions (22–28 °C with relative humidity of 54–63%). To determine the survivability of airborne E. coli, an AGI-30 bioaerosol sampler (AGI-30) was used to collect the E. coli at 0 and 20 min after the aerosolization. The half-life time of airborne E. coli was then determined by comparing the number of colony-forming units (CFUs) of the two samplings. To determine the survivability of settled E. coli, four sterile Petri dishes were placed on the chamber floor right after the aerosolization to collect settled E. coli. The Petri dishes were then divided into two groups, with each group being quantified for culturable E. coli concentrations and dust particle weight at 24-h intervals. The survivability of settled E. coli was then determined by comparing the number of viable E. coli per milligram settled dust collected in the Petri dishes in the two groups. The survivability of E. coli in the poultry litter sample (for aerosolization) was also determined. Results show that the half-life time of airborne E. coli was 5.7 ± 1.2 min. The survivability of E. coli in poultry litter and settled E. coli were much longer with the half-life time of 15.9 ± 1.3 h and 9.6 ± 1.6 h, respectively. In addition, the size distribution of airborne E. coli attached to dust particles and the size distribution of airborne dust particles were measured by using an Andersen impactor and a dust concentration monitor (DustTrak). Results show that most airborne E. coli (98.89% of total E. coli) were carried by the dust particles with aerodynamic diameter larger than 2.1 µm. The findings of this study may help better understand the fate of E. coli transmitted through the air and settled on surfaces and evaluate the impact of airborne transmission in poultry production.

Insecticidal efficacy and safety of Phoxim and influence on hematological, biochemical, and antioxidant profiles in German Shepherd dogs

Background

Dogs' health and welfare enhancement can be achieved using some prophylactics and immunization go with strict hygienic and optimum biosecurity measures.

Aim

Exploration of the insecticidal action of Phoxim^® for combating Rhipicephalus sanguineus infestation in dogs and its prophylactic influences on the blood indices, biochemistry, antioxidant enzymes, and cortisol hormone in healthy and infested dogs.

Methods

Twenty German Shepherd male dogs at 1 year old and 44.0 kg were divided randomly into four groups of five dogs in four separate Kennels with optimum biosecurity measures. The 1st group (G1) was artificially infested with R. sanguineus and treated with Phoxim^®, the 2nd (G2) was non-infested and treated with Phoxim^®, the 3rd (G3) was infested with R. sanguineus and not treated (positive control), and the 4th (G4) was accounted as negative control (non-infested and non-treated). A total of 160 (80 whole blood and 80 sera) samples were collected.

Results

Parasitological examination revealed prominent characteristic features of R. sanguineus such as a distinct anal groove, the basis capitulum is hexagonal and lateral, the palpi are short, the second segment of the palpi as long as wide and not produced laterally, and the spiracular plate is comma-shaped and consists of stigma, peritreme, and tail. The results conveyed highly significant (p < 0.01) enhancement in erythrocytes, leukocytes, hematohiston, hematocrit, hemoglobin centering, granulocytes, alanine aminotransferase, random blood sugars, triglycerides, and total cholesterol, and highly significant (p < 0.01) declines of all measured antioxidant enzymes in treated non-infested dogs.

Conclusion

Phoxim^® proved efficient insecticidal activity with optimum safety and can be brought into play in the prophylactic biosecurity measures installed to eradicate external parasitism in dogs.

Nile tilapia bones as eco-friendly alternative in water treatment and enhancing performance and immunity in broiler chickens

Background

Water pollution has become a major threat to the environment and the living so an eco-friendly bio-filter was chosen for its merits over conventional techniques.

Aim

Investigating the purifying activities of the Tilapia bone powder against inorganics, heavy metals, and microbial water pollutants and its impacts on performance, biochemical and antioxidant levels, cortisol and immunoglobulin concentrations, and intestinal microbiota in challenged broiler chickens.

Methods

The in-vitro activity of Tilapia bone powder was evaluated against magnesium chloride and lead nitrate using tube minimal inhibitory concentration (MIC), as well as against Escherichia coli O1527:H7, Salmonella Typhimurium, Mycoplasma gallisepticum, Aspergillus niger, Trichophyton mentagrophytes, and Candida albicans using a 96-micro-well MIC. A total of 250 1-day-old Hubbard chicks were divided into five groups on a deep litter system. Chicks were supplemented daily with Tilapia bone powder (1 g/l) for 4-6 hours from the 3rd day. Challenges were served on the 7th, 14th, 21st, 28th, and 35th days for four broiler groups using magnesium chloride (100 mg/l), lead nitrate (350 mg/l), E. coli (2.4 × 10¹² CFU/ml), S. Typhimurium (1.8 × 10⁸ CFU/ml), respectively, and the 5th group was assigned as a control. A total of 2,250 samples (90 Tilapia-pollutants mixes, 480 Tilapia-microbial mixes, 240 sera, 240 intestinal swabs, and 1,200 tissue samples) were collected.

Results

Tilapia bone powder 1% reveals a 100% reduction in the lead after 1 hour, total and calcium hardness after 0.5 hours, as well as 100% killing efficacy against E. coli O1527:H7, S. Typhimurium, M. gallisepticum, A. niger, T. mentagrophytes, and C. albicans after 0.5, 1, 1, 1, 1, and 1 hour, respectively. Tilapia bone powder 1% treated water reveals highly significant (p < 0.01) increases in dissolved oxygen and declines in physicochemical and microbial parameters compared with tap water. Challenged treated broilers revealed highly significant (p < 0.01) increases in weight gains, performance index, body weights, carcasses, and organs weights, immunoglobulin concentrations, and antioxidant levels, as well as highly significant (p < 0.01) improvements in feed conversions, feed and water intakes, biochemical profile, cortisol hormone, and intestinal microbiota.

Conclusion

Tilapia bone powder provided significant in-vitro adsorptive and antimicrobial actions, as well as supported the broiler chickens to mitigate the polluted water stress accompanied by enhanced performance, carcass quality, immunity, and intestinal microbiota.

Prevalence of Eimeria sp. in Broiler Poultry Houses with Positive and Negative Pressure Ventilation Systems in Southern Brazil

Coccidiosis is an enteric disease caused by protozoa of the Eimeria genus and is of great economic relevance in industrial aviculture. The objective of this work was to determine the prevalence of Eimeria sp. in broiler poultry houses with positive (System 1) and negative (System 2) pressure ventilation and assess the associated factors. A transversal study was conducted using 8 random broiler chickens from 64 houses (n = 512) and macroscopic and histologic evaluation of the intestines, as well as PCR for Eimeria sp. The prevalence of Eimeria sp. was 90.6% (95% confidence interval [CI]: 97.8-83.5), with 93.8% (95% CI: 100-85.4) in System 1 and 87.5% (95% CI: 99.0-76.0) in System 2. The most prevalent species was Eimeria acervulina, and the most common combination was Eimeria acervulina, Eimeria maxima, and Eimeria tenella. System 2 and the negative Eimeria subgroup showed the best results for feed conversion and daily weight gain. By evaluating litter treatment, we found that quicklime reduced the risk of presence of Eimeria maxima and Eimeria tenella. In conclusion, Eimeria sp. had a high prevalence in both systems, with a predominance of mixed infections. System 2 and negative flocks showed the best zootechnical results.

The efficiency of natural-ecofriendly clay filters on water purification for improving performance and immunity in broiler chickens

Background

Innovative water treatments and purification processes have become a point of interest to provide solutions and meet the basic water requirements and demands. Clay plays a key role in environmental protection from pollutants through ion exchange and/or adsorption.

Aim

The study evaluated the adsorption and antimicrobial efficiency of clay in purifying polluted water, as well as the influence of clay-purified water on performance, immunity, and microbial counts.

Methods

The experimented 280 one-day-old Hubbard broilers were divided into seven groups on a deep litter system. Polluted water (lead nitrate; 500 mg/l, calcium sulfate; 80 mg/l, yeast extract 5%; 5 mg/l, diazinon; 2.5 ml/l, Salmonella Typhimurium; 1.5 × 106 CFU/ml, and Eimeria tenella; 1 × 105 OPG/ml) was filtered using plastic basins of 1 m3 supplied with 60 cm layer of clay. Broiler groups (G1 to G6) were supplied with clay-filtered and G7 with control tape water. A total of 2,182 samples, including 54 water samples, 266 sera, 266 duodenal swabs, 266 breast muscles, 266 fecal samples, and 1,064 organs including liver, spleen, heart, and bursa of Fabricius were collected.

Results

Weight gains, performance indices, water intakes, water/feed intake ratios, live body weights, carcasses weights, edible and immune organs' weights, immunoglobulin G and M, total antioxidant capacity, lactate dehydrogenase, malondialdehyde, and superoxide dismutase revealed highly significant (p < 0.01) increases in all broiler groups supplemented with clay-filtered water compared to the control group. Meanwhile, total protein, alanine aminotransferase, creatinine, glucose, triglycerides, total cholesterol, cortisol hormone, total bacterial and Enterobacteriaceae counts, total Salmonella counts, and E. tenella counts revealed highly significant (p < 0.01) declines in all broiler groups supplemented with clay-filtered water compared to the control group.

Conclusion

Clay filters provided high filtration, adsorption, and antimicrobial efficiency against polluted water, enhanced water quality, and improved performance and immunity in broiler chickens.

Moderations in performance, immunity, tissue architecture, and vaccine viability induced by water magnetization in broiler farms

Background and Aim:

Water magnetization contributes to increased molecular ionization and fluidity, which improves biological activities. This study tests the influence of magnetic water on the viability of the Newcastle vaccine and the survival of Escherichia coli and SalmonellaTyphimurium, as well as the influence of magnetic water in face of water impurities’ challenges on performance, immunity, and tissue architecture in broiler chickens.

Materials and Methods:

An in vitro 96-micro-well plate minimal inhibitory concentration was utilized to test the influence of water, saline, and magnetic water on Newcastle vaccine viability and E. coli O157:H7 and S. Typhimurium survival. The 245 experimental 1-day-old female Ross^® 308 broilers used in this study were divided into seven groups of 35 birds each. Broilers were provided with magnetic drinking water (13,200 gausses) for 6 h daily from the 5^th day and were challenged on days 14, 21, 28, and 35 using sodium chloride (700 mg/L), calcium sulfate (80 mg/L), lead acetate (500 mg/L), yeast extract 5% (5 mg/L), diazinon (2.5 mL/L), and E. coli O157:H7 (1.6 × 10⁹ CFU/mL). A total of 2040 samples (96 diluent-Newcastle virus vaccine mixes, 96 microbial-magnetic water mixes, 231 sera, 231 intestinal swabs, and 1386 organ samples) were collected.

Results:

An in vitro trial revealed highly significant (p<0.01) declines of 94.13%, 84.53%, and 10.31% in the Newcastle vaccine titer in water, saline, and magnetic water, respectively, and 54.91% and 39.89% in E. coli O157:H7 and S. Typhimurium survival, respectively, after 4 h. In all challenged groups, broilers exhibited highly significant (p<0.01) increases in performance, carcass/organs weight, immunoglobulin G, immunoglobulin M, and Lactobacillus counts; significant improvement in tissue architecture and biochemical parameters; and highly significant (p<0.01) reductions in cortisol, superoxide dismutase, and total bacterial and Enterobacteriaceae counts.

Conclusion:

Magnetic water could maintain vaccine viability and vaccination efficiency, reduce microbial survival, and minimize the negative influence of all induced challenges.

Influence of temperature on sporulation of Eimeria arloingi and Eimeria perforans oocysts

Eimeriosis of farm animals is one of the most widespread parasitic diseases in the world. In the conditions of the steppe zone of Ukraine Eimeria perforans is more common in rabbits and E. arloingi in sheep and goats. Study of factors which influence the development of these protists on the soil surface is one of the major challenges for veterinarians working for large livestock companies and fighting against eimeriosis. Environmental temperature is able to change the speed of sporulation of oocysts Eimeria. Five values of temperature (15, 20, 25, 30, and 35 °C) were used in a laboratory experiment in vitro. At 15 °C, the process of sporulation of E. arloingi and E. perforans in 100% of cases ended on the eighth day. With increase in temperature to 35 °C, the duration of sporulation decreased to three days. When the temperature was 30 °C the completion of sporulation was observed in more than 50% of the oocysts of E. arloingi on the second day, and for E. perforans on the third day. High-speed sporulation at elevated temperatures under conditions of global warming can result in the increasing spread of eimeriosis among wild and domestic animals.

Preventive antimicrobial action and tissue architecture ameliorations of Bacillus subtilis in challenged broilers

Background and Aim:

Probiotics improve intestinal balance through bacterial antagonism and competitive exclusion. This study aimed to investigate the in vitro antimicrobial activity, as well as the in vivo preventive, immunological, productive, and histopathological modifications produced by probiotic Bacillus subtilis.

Materials and Methods:

The in vitro antimicrobial activities of B. subtilis (5×10⁶ CFU/g; 0.5, 1.0*, 1.5, and 2.0 g/L) were tested against Escherichia coli O157: H7, Salmonella Typhimurium, Candida albicans, and Trichophyton mentagrophytes after exposure times of 0.25, 0.5, 1, and 2 h using minimal inhibitory concentration procedures. A total of 320 1-day-old female Ross broiler chickens were divided into five groups. Four out of the five groups were supplemented with 0.5, 1.0*, 1.5, and 2.0 g/L probiotic B. subtilis from the age of 1 day old. Supplemented 14-day-old broiler chickens were challenged with only E. coli O157: H7 (4.5×10¹² CFU/mL) and S. Typhimurium (1.2×10⁷ CFU/mL). A total of 2461 samples (256 microbial-probiotic mixtures, 315 sera, 315 duodenal swabs, and 1575 organs) were collected.

Results:

The in vitro results revealed highly significant (p<0.001) killing rates at all-time points in 2.0 g/L B. subtilis: 99.9%, 90.0%, 95.6%, and 98.8% against E. coli, S. Typhimurium, C. albicans, and T. mentagrophytes, respectively. Broilers supplemented with 1.5 and 2.0 g/L B. subtilis revealed highly significant increases (p<0.01) in body weights, weight gains, carcass weights, edible organs’ weights, immune organs’ weights, biochemical profile, and immunoglobulin concentrations, as well as highly significant declines (p<0.01) in total bacterial, Enterobacteriaceae, and Salmonella counts. Histopathological photomicrographs revealed pronounced improvements and near-normal pictures of the livers and hearts of broilers with lymphoid hyperplasia in the bursa of Fabricius, thymus, and spleen after supplementation with 2.0 g/L B. subtilis.

Conclusion:

The studies revealed that 1.5-2.0 g of probiotic B. subtilis at a concentration of 5×10⁶ CFU/g/L water was able to improve performance, enhance immunity, and tissue architecture, and produce direct antimicrobial actions.

Assessment of the Effectiveness of Pre-harvest Meat Safety Interventions to Control Foodborne Pathogens in Broilers: a Systematic Review

Purpose of Review

Ensuring broilers’ meat safety is a priority to policy makers, producers, and consumers. This systematic review aims to update the recent knowledge on pre-harvest interventions to control main foodborne pathogens in broilers and to assess their effectiveness.

Recent Findings

A total of 815 studies were retrieved from PubMed® and Web of Science for 13 pathogens. In total, 51 studies regarding Campylobacter spp., Salmonella spp., VTEC, ESBL-AmpC Escherichia coli, and Clostridium perfringens were included in this review.

Summary

Research mostly focused on Salmonella spp. and Campylobacter spp. Biosecurity and management interventions had mixed outcomes, while the effectiveness of feed additives, though intensively researched, remains controversial. Research on other pathogens (i.e. ESBL-AmpC E. coli/Salmonella, and Toxoplasma gondii) was scarce, with publications focusing on epidemiology and/or on source-attribution studies. This is also true regarding research on Listeria monocytogenes, Bacillus cereus, Clostridium botulinum, Clostridium perfringens, and Staphylococcus aureus as these are frequently controlled by post-harvest interventions. Overall, studies on recent developments of novel pathogen-specific immunisation strategies are lacking.

Associations between animal-based measures at 11 wk and slaughter data at 20 wk in turkey toms (Meleagris gallopavo)

To monitor animal welfare on a commercial scale, systematic collection and evaluation of slaughterhouse data is the most feasible method. However, we need to know whether slaughterhouse data retrospectively and reliably reflect information about the birds' welfare on-farm. The aim of this study was therefore to investigate associations between animal-based welfare measures in flocks of turkey toms at 11 wk of age recorded with the transect walk and slaughter data at 20 wk of age. A total of 20 commercial flocks of turkey toms were visited, where an observer walked the transects in a random order and recorded the total number of birds per transect that were immobile, lame, with visible head, tail, or wing wounds, small, featherless, dirty, sick, terminal, or dead. Slaughterhouse data were provided for each flock. Univariate and multivariate linear regression models were used to investigate the associations between on-farm and slaughterhouse measures. Increased prevalence of immobile toms at week 11 resulted in more birds rejected at slaughter owing to leg issues (P = 0.02) and airsacculitis (P < 0.001). More lame birds on-farm were associated with an overall higher rejection rate at slaughter (P < 0.001). Flocks with more featherless birds had significantly more birds being rejected at slaughter owing to skin issues (P = 0.02). More dirty birds at week 11 resulted in more birds being rejected owing to airsacculitis at slaughter (P < 0.001). A higher mortality on-farm was associated with more birds rejected for being too small (P = 0.04). In conclusion, significant associations between animal-based measures of turkey toms as assessed by the transect walk method on-farm at 11 wk and slaughter data at 20 wk were identified.

Prophylactic impact of nano-selenium on performance, carcasses quality, and tissues' selenium concentration using reversed-phase high-performance liquid chromatography during microbial challenge in broiler chickens

Background and Aim:

Nano-selenium (NS) supplementation contributes in improving productivity, performance, and meat quality while reducing public health concern. Influence of NS and inorganic selenium (Se) water additive on performance, carcass quality, immunoglobulin concentration, intestinal microbiota, Se tissue concentrations, and tissue architecture was studied.

Materials and Methods:

Two-hundred and sixty 1-day-old Hubbard chicks were randomly grouped into five groups (5×52) and supplemented with 0.5 and 1.0 mL of NS and inorganic Se (100 mg.L⁻¹). G1, G2, G3, and G4 were challenged with Escherichia coli O157: H7 2.6×10⁸ on the 14^th day. A total of 2250 samples, including 250 sera, 250 intestinal swabs, and 1500 organ and tissue samples as liver, spleen, heart, bursa, intestine, and breast muscles, and 250 eviscerated carcasses were collected.

Results:

The results revealed a highly significant increase (p<0.01) in live body weights, weight gains, performance indices, carcasses, and organs weights, whereas immunoglobulin G and M concentrations in broilers treated with 0.5 and 1.0 mL NS, respectively, synchronized reveal a highly significant decline (p<0.01) in total bacterial and Enterobacteriaceae counts of intestinal swabs and breast muscles, final pH₂₄, and drip loss in broilers treated with 0.5 and 1.0 mL NS, respectively. Meanwhile, water holding capacity revealed no significant differences between all groups. Reversed-phase high-performance liquid chromatography examination revealed the earlier disappearance of NS residues than inorganic Se from the broiler’s liver and muscles. Histopathological photomicrographs of the liver, spleen, bursa of Fabricius, and intestine, as well as, the immunohistochemistry of intestinal sections revealed superior tissue architecture in broilers treated with NS contrary to inorganic Se.

Conclusion:

The study showed significant stimulation actions of NS on performance, immunity, carcass and meat quality, intestinal and muscles’ bacterial load as well as short withdrawal period and nearly normal cellular architecture compared to inorganic Se.

Assessment of biosecurity measures in broiler's farms in the Suez Canal area - Egypt using a seasonal prevalence of Salmonellosis

Background and Aim

Biosecurity practices are a must in broiler farms to reduce the risk of infectious agents. This study aimed to evaluate biosecurity measures in nine broiler farms in the Suez Canal area - Egypt with measuring the seasonal prevalence of salmonellosis.

Materials and Methods

A cross-sectional study was conducted on randomly selected nine broiler farms of different housing systems based on the ventilation methods from March 2018 to April 2019. A total of 12,600 samples (6480 environmental, 4320 non-environmental, 1080 sera, and 720 live birds) were collected during four successive seasons.

Results

Highly significant increases (p<0.01) were recorded in body weight gains in opened and closed-houses during summer; in food conversion ratios in opened-houses during winter and in closed-houses during winter and fall; in performance indices in opened-houses during summer and closed-houses during winter; and in live body weights, carcasses weights, liver, spleen, and bursa's weights in opened-houses during spring and in closed-houses during fall. Highly significant increases (p<0.01) were recorded in total bacterial, Enterobacteriaceae, and Salmonella counts in opened-houses during spring and in closed-houses during summer, in Salmonella Typhi O and H, and Salmonella Paratyphi A and B sera titer in opened-houses during summer and closed-houses during fall. Biosecurity measures scored 34 out of 43 with an average salmonellosis prevalence of 6.0% in closed-house and 24 out of 43 with an average salmonellosis prevalence of 24.67% in opened-house broiler farms.

Conclusion

Weak biosecurity measures in broiler houses (opened and closed) were not sufficient to prevent the entrance and multiplication of Salmonella spp. Disciplines, commitment, and regulations of biosecurity need to be enforced in broiler houses to prevent the introduction and spread of diseases.

Impact of lighting color and duration on productive performance and Newcastle disease vaccination efficiency in broiler chickens

Background and Aim

Manipulating lighting colors and regimens is considered an effective mean for improving broiler productivity. The influence of red, blue, and white light-emitting diode (LED) was investigated using three different regimens of lighting and darkness; continuous 23 h light (L):1 h dark (D), continuous 18 h L:6 h D, and intermittent 16 h L:8 h D hours on the performance, carcass weight (CW), feed and water intake (WI), serum glucose (GLUCO), triglycerides (TG), and cholesterol (TC), intestinal bacterial load, growth and metabolic hormones, and efficiency of Newcastle disease (ND) vaccine.

Materials and Methods

A total of 252 1-day-old Ross broilers on deep litter were divided into nine groups. The 1^st, 4^th, and 7^th groups were exposed to continuous 23L:1D, the 2^nd, 5^th, and 8^th groups were exposed to continuous 18L:6D, and the 3^rd, 6^th, and 9^th groups were exposed to intermittent 16L:8D (4L:2D, 4 times) lighting regimen using red, blue, and white LED lights, respectively. A total of 1350 samples (225 sera, 225 swabs, and 900 organ samples) were collected.

Results

Blue LED group revealed a highly significant increase (p<0.01) in live body weight, body weight gain, performance index, CW, spleen, heart, and liver weights, and anti-ND antibody titer, as well as a highly significant decline (p<0.01) of feed intake, WI, GLUCO, TG, TC, growth hormone, insulin, tri-iodothyronine (T3), tetra-iodothyronine (T4), total bacterial count (TBC), and total Enterobacteriaceae count compared to red and white LED lights in all tested lighting regimens. Continuous 23L:1D and 18L:6D regimens were significantly (p<0.01) superior to intermittent 16L:8D in their influence on the performance, CW, biochemistry, hormonal profile, and bacterial load.

Conclusion

The blue LED light associated with continuous 18L:6D or 23L:1D h regimen is highly recommended in broiler houses for their enhancing the productive performance, growth, and immunity.