This study aimed to characterize the physicochemical properties of broiler poultry litter (BPL) produced from intensively reared commercial broiler farming areas in tropical zone of Tamil Nadu, India. The BPL samples were collected from 110 commercial poultry farms at the end of the production cycle (6th week), further 20 samples were collected from the point of utility. The dry matter (DM), moisture, ash, organic matter (OM), and organic carbon (OC) from the manure samples were 83.04 ± 0.77, 16.96 ± 0.77, 27.08 ± 1.18, 72.92 ± 1.18 and 42.39 ± 0.69 per cent respectively. The pH, Electrical conductivity (EC) (ds m-1), and Kjeldahl Nitrogen (N) were 8.43 ± 0.06, 5.74 ± 0.13, and 24.2 ± 0.84 g kg-1 respectively. The BPL from the cement floor had higher levels of P and K (12.74 and 13.28 ) than the mud floor (10.88 and 10.96). According to the findings of this study, BPL as such at the end of the production cycle is rich in OM, nitrogen, macro and micro minerals at the same time at the point of utility there was a loss of OM, N, and concentration of minerals was noticed, which advocate proper storage and composting process.

The potential benefits of bioconversion of commercial broiler poultry litter (PL) to vermicompost (with Eudrilus eugeniae) were studied by optimizing the carbon-nitrogen ratio (C/N) using coconut (Cocos nucifera) coir pith (CP) and farm yard manure (FM) as co-substrate. In this experiment, after optimizing the C/N at the levels of 25, 30, and 35, the pre-composting of the PL followed by vermicomposting was done, and the PL and FM alone were used as the control group. After pre-composting, the earthworms (Eudrilus eugeniae) were introduced, and the vermicomposting process was continued for 90 days and the vermicompost samples were analyzed on the 45th and 90th days. The study revealed a significantly (P

The use of anti-microbial drugs and coccidiostats in poultry farming is widespread, with a significant proportion of these drugs being excreted and released into the environment. The residues of such drugs in poultry litter (PL) can result in the development of antibiotic-resistant bacteria. The impact of different biotic treatments (aerobic, anaerobic, and stacking) on broiler litter (BL) before use as animal feed has not been studied extensively, nor have the differences between antimicrobial-dependent and independent broiler farms been investigated. This study aimed to determine the resistant bacteria in BL used as ruminant feed before and after litter treatment. The results showed that the most resistant bacteria before BL treatment were Enterococcus species. The study also found that the quantity of amoxicillin-resistant Enterococcus detected in samples from antimicrobial-dependent farms was significantly higher than in those from antimicrobial-independent farms. Additionally, 14% of bacteria were multi-resistant to tetracycline, sulfafurazole, and erythromycin in antimicrobial-independent farm litters, significantly lower than those measured in antimicrobial-dependent broiler farm litter. This study highlights the importance of better understanding, regulating, managing, and using animal waste appropriately to reduce the number of antibiotic-resistant bacteria and minimize the use of antimicrobials that carry high risks for animals, humans, and the environment

Insect meal as a protein source has been considered a sustainable way to feed animals. H. illucens and T. molitor larvae meal are considered high protein sources for poultry, also presenting considerable amounts of fatty acids, vitamins, and minerals. However, other potential components in insect meal and insect oil have been more studied nowadays. Chitin, lauric acid, and antimicrobial peptides can present antimicrobial and prebiotic functions, indicating that low inclusions of insect meal can beneficially affect broilers` health and immune responses. This systematic review was developed to study the impact of insect products on health parameters of broilers, and a metanalysis was conducted to evaluate the effects on performance. A database was obtained based on a selection of manuscripts from 2016 to January 2023, following the mentioned parameters. There were positive effects of both H. illucens and T. molitor meal or oil products on poultry health status, especially in microbiota population, immune responses, and antimicrobial properties. The average daily gain was greater in broilers fed T. molitor meal compared to H. illucens meal (p = 0.002). The results suggest that low levels of insect meal were suitable for broilers, without result in negative effects on performance, while the insect oil can totally replace soybean oil without negative impacts.

Anti-microbial drugs and coccidiostat compounds are commonly used in poultry farming. These compounds are subsequently excreted and released into the environment via broiler litter (BL) and can re-enter the food chain as fertilizer and/or animal feed. Residues of such drugs can encourage the appearance of antibiotic-resistant bacteria (ARB), as well as toxicity, when found in animal feed. The aim of this study was to develop a multi-residue analytic method for assessing 30 an-ti-microbial drugs and coccidiostats associated with BL and investigate the effects of stacking treatment on anti-microbial and coccidiostat residue degradation in BL used for ruminant feed at the lab-scale. Today, most analytical methods used to identify and quantitate these drug residues are traditional, and may be specific to some antimicrobials. All call for lengthy sample preparation and may present limitations in assessing broiler litter. Such conventional mul-ti-anti-microbial/coccidiostat residue detection assays employ liquid-liquid extraction (LLE) and solid phase extraction (SPE) for sample purification. In our research, LLE and SPE were replaced by Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) clean-up steps for 30 an-ti-microbials and coccidiostats used in broiler farming and detection by liquid chromatography mass spectrometry (LC/MS/ MS). Using this method, recoveries were 70-120%, with the exception of norfloxacin and narasin, which showed recoveries of 67 and 68%, respectively. This analytical meth-od results show that eight samples were not detected in 42 samples, while in 34 samples, one or more drugs were present. Eighteen anti-microbial and coccidiostat residues were detected dur-ing one year sample collaction. The most frequently detected residues were narasin, nicarbazin, monensin, robenidine, oxytetracycline, chlortetracycline, norfloxacin and sulfachloropyridazine, seen at levels from 0.4 to 8.9 mg•kg-1 (ppm). Nineteen anti-microbials and one coccidiostat were degraded to 95% by the stacking treatment. However, tilmicosin and eight coccidiostats persisted in litter (26-100%). The use of antimicrobials and coccidiostats in animal farming is of paramount concern with respect to human, animal and environmental contamination issues and as a source of resistant pathogenic bacteria. Still, most farmers use BL as ruminant feed and fertilizer without processing. Even though the effects of the stacking treatments on degradation of antimicrobials were significantly high, the degradation of coccidiostats and tilmicosin was limited. Clearly, BL should be treated and supervised before use as feed supplement or for land application. Hence, the present method, designed to support these goals, was optimized in terms of sensitivity and se-lectivity for the analytes addressed.

In this study, broilers were selected as the research object to investigate the effects and mechanism action of dietary gallic acid (GA) supplementation on growth performance, meat quality, antioxidant capacity, and muscle fiber-related gene expression. A total of 750 one-day-old healthy 817 male crossbred broiler chickens were divided into five treatment groups, with six replicates per group: control group (CON), basal diet, basal diet with lipopolysaccharide challenge (LPS), basal diet with 150, 300, 450 mg/kg GA supplementation and LPS challenge (GA150, GA300, GA450). On days 14, 17, and 20, chickens in the LPS, GA150, GA300, and GA450 groups received intramuscular injections of LPS, while chickens in the CON group received saline. Compared with the LPS group, adding GA (GA150 and GA300) significantly increased the average daily gain (ADG) of broiler chickens from 1 to 50 days old (p < 0.05), and had the tendency to increase average daily feed intake (ADFI) (p = 0.078). Dietary addition of 450 mg/kg GA significantly reduced the pH value of breast muscle at 45min after slaughter (p < 0.05), and as the level of GA addition increased, the pH value first decreased and then increased. Compared with the LPS group, adding 450mg/kg GA significantly increased the brightness of breast muscles at 45min and 24h after slaughter (p < 0.001). Dietary supplementation of 450 mg/kg GA significantly decreased the total volatile basic nitrogen (TVB-N) content of post-mortem breast muscle (p < 0.05). Adding 450 mg/kg GA could significantly increase C22:6n-3 concentration in breast muscle (p < 0.05). Different GA levels had no significant effect on the intramuscular fat (IMF) content of broiler breast muscle (p > 0.05). Adding GA (GA150 and GA300) significantly increased (p < 0.05) the total superoxide dismutase (T-SOD) activity in the breast muscle after LPS stimulation, significantly increased (p < 0.05) the catalase (CAT) activity, and significantly reduced (p < 0.05) malonic dialdehyde (MDA) production, and had the tendency to increase glutathione peroxidase (GSH-Px) activity (p = 0.066). In addition, dietary supplementation of GA significantly increased the expression levels of myosin heavy chain (MyHC) I and MyHC IIa in breast muscles (p < 0.05), and significantly decreased the expression level of MyHC IIx (p < 0.05). In summary, dietary addition of GA can alleviate the stress response on the growth performance of broiler chickens and improve antioxidant capacity and meat quality. The appropriate amount of dietary GA at each stage was 300 mg/kg.

Peroxisome proliferator-activated receptors (PPARs) are important targets for cannabidiol (CBD), which mediate many of its biological actions. The hypothesis of the present research assumed that PPARs affect the gut response to different challenge factors in chickens (C. perfringens vs lipopolysaccharides (LPS) from E. coli), and CBD can mediate the pathways of this response. The study proved that CBD and challenge factors significantly affect the expression level of PPARα (P=0.001) and selected genes determining gut barrier function. A positive correlation was demonstrated between PPARs and genes involved in the formation of tight junctions, immune and oxidative stress responses in chickens. Dietary supplementation with CBD actively mediated the expression rate of PPARs, but the mechanism of interaction between CBD and PPARs was different depending on the stress factor used. The addition of CBD to the birds’ diets did not contribute to reducing intestinal permeability under induced stress conditions and did not cause a stress-inducing effect resulting in the increase of cortisol and endotoxin concentration in the blood. CBD also supported the mechanisms of protecting intestinal cells from cytotoxic effects in a C. perfringens challenge. This study indicates the importance of research towards understanding the mechanisms of PPARs as a target for enhancing intestinal barrier function, provides new results on the biological action of CBD in chickens and shows a constant PPARs association with the jejunum mucosa of birds.

The contractual relationship between the processing firm and the broiler smallholder presents incessant conflicts of interest and inequality due to technical and economic discrepancies, leading to an undervaluation of the producers' remuneration. This study aims to deepen the discussions in searching for a more balanced monetary exchange between processing firms and broiler smallholders based on scientific aspects. For this, the Emergy theory and its concepts were used in considering a representative broiler production system at Concórdia, Santa Catarina, Brazil. This study suggests the inclusion of cultural information in the Emergy-based model calculation. For the broiler smallholder, cultural information showed the highest Emergy contribution (62.95%; transformity = 1.73 ×10^8). However, only considering cultural information was not sufficient to increase the sustainability of the broiler production system. The results highlight an imbalance of the monetary exchange between agroindustry and broiler smallholder payment for both the economic and Emergy-based payment. Both estimated payments were higher than the practiced payment value (0.24 USD/broiler as well as 0.32 USD/broiler and 1.62 EmUSD/broiler, respectively). Thus, evaluating the “(eco)cost” in Emergy-based accounting recognizes that production depends not only on tangible physical resources but also on knowledge, skills and information (“iceberg of value” thinking). Policy and decision makers must, therefore consider the promotion of public policies that subside initiatives, including social and environmental welfare programmes.

In a completely randomized design (CRD), 400 day-old Ross 308 broilers were randomly allotted to 5 diets with 0, 5, 10, 15 and 20% MSC, each with 8 replicates of 10. Weekly feed intake (FI), body weight gain (BWG) and feed conversion efficiency (FCE) were calculated whilst haemato-biochemistry was measured at d42. Overall, FI was linearly (P &lt; 0.05) and quadratically (P &lt; 0.01) decreased by MSC, of which the optimum inclusion was 15%, as BWG was linearly (P &lt; 0.001) and quadratically (P &lt; 0.05) decreased and FCE linearly decreased (P &lt; 0.01) by MSC, of which the optimum dietary inclusion was 10%. Also, MSC linearly and quadratically decreased slaughter weight (P &lt; 0.001 and P &lt; 0.05, respectively), hot carcass weight (P &lt; 0.001 and P &lt; 0.05, respectively) and cold carcass weight (P &lt; 0.001 and P &lt; 0.05, respectively). Similarly, it linearly decreased white blood cells (P &lt; 0.01) and lymphocytes (P &lt; 0.05) as it linearly (P &lt; 0.001) and quadratically (P &lt; 0.01) decreased symmetric dimethylarginine (SDMA) and linearly (P &lt; 0.001) increased serum cholesterol. In conclusion, up to 10% MSC can be incorporated into broiler diets in replacement of SBM without adverse effects.

The importance of enzymes in the poultry industry is ever increasing because they help to extract as many nutrients as possible from the raw material available and reduce environmental impacts. Therefore, an experiment was conducted to examine the effect of a natural enzyme complex (ASC) on diets low in AME, Ca and P. Ross 308 broilers (n = 900) were fed one of four diets: (1) positive control (PC) with no enzyme added (AME 12.55 MJ/kg, AVPhos 4.8 g/kg and AVCal 9.6 g/kg); (2) negative control (NC) with no enzyme added and down-specified for AME, Ca and P (AME 12.18 MJ/kg, AVPhos 3.3 g/kg, AVCal 8.1 g/kg); (3) negative control plus ASC at 200 g/t; and (4) negative control plus ASC at 400 g/t. Broiler performance, digesta viscosity, tibia mineralization and mineral content were analyzed at d 21. Between d 18 and 20, excreted DM, GE, total nitrogen, Ca, and P were analyzed. ASC at 200 g/t and 400 g/t improved the FCR (p = 0.0014) significantly when compared with that of the NC. There were no significant differences in BW or FI between the treatments. Birds fed ASC at 200 g/t and 400 g/t had significantly improved digesta viscosity (p &lt; 0.0001) compared with that of the PC and NC and had significantly higher excreted DM digestibility (p &lt; 0.01) than the NC and the PC with 400 g/t ASC. ASC inclusion significantly improved P retention (p &lt; 0.0001) compared with that in the PC. Ca retention was significantly increased by 400 g/t ASC compared with that in the PC and NC (p &lt; 0.001). AME was significantly higher (p &lt; 0.0001) for all treatments compared with that in the NC. There were no significant differences between treatments for any of the bone measurements. This study showed that feeding ASC can support the performance of broilers when fed a specification reduced in Ca, P and AME, with the greatest results being seen with the higher inclusion level of ASC.

This review has been realized within the agribusiness sector and experiments the Transaction Cost Theory a branch of the New Institutional Economy which explain market failure caused by many factors. Transaction costs are associated with carrying a transaction between buyers and sellers. This study has been conducted between 2014 and 2017; and has collected data from 11 broiler producers in Jezzine, Lebanon, about: Production costs, capital investment, revenues, land tenure, access to infrastructure, and information about the contract. The propensity score matching method is used to compare the effect of participating in contract farming and to solve the hypotheses, which say: There is a positive relationship between contract farming and the economic benefits of broiler producers and the development of the broiler sector in Jezzine District. Findings from farmer’s interviews indicated that sustainability, guaranteed price, risk reduction, credit facilities and technical aids are the main reasons for signing a contract. In contrast, Farmers have expressed problems concerning the contractors’ responsibilities such as delay in payment and delivery. Also, when prices are high, it was argued that farmers were selling the products in the open market.

Contract between grower and integrator has been used extensively in broiler industry all over the world. One important advantages of contract is risk management, in which contract shifts a portion of grower risk to integrator. Thus, this paper attempted to measure the amount of risk shifted from grower to integrator and the consequences of this benefit to grower. Using a panel data of actual production records of 46 Indonesian broiler growers for the period of January 2014 through December 2017, we systematically measure the amount of risk shifted to integrator and its consequences to grower. The results showed that 78.43% grower risk is shifted to integrator. However, to acquire this benefit grower receive 15% less income. Furthermore, grower face the possibility of losing their asset and stopping their production as the consequences of entering contract.

Nowadays, animal breeders look for effective innovations to care animal health. Use of probiotics, postbiotics, parabiotics and the other beneficial natural substances are dominated. Mundticin-like substance EM 41/3 is thermo-stable bacteriocin (postbiotic) with a broad antimicrobial spectrum. In this study its effect in broiler rabbits was assessed. Rabbits represent food-derived animal and they are also suitable animal model. The parameters tested were analyzed by validated methods. Administration of MLS EM 41/3 produced by non-autochthonous strain Enterococcus mundtii EM 41/3 lead to significant increase of parameter immunity-phagocytic activity, while it did not influence microbiota composition. It also did not influence blood biochemistry and no oxidative stress was noted. Moreover, higher growth parameters were noted and also stimulated hydrolytic activity. Finally, no negative influence on rabbit meat quality was noted. Postbiotic MLS EM 41/3 administration in feeding strategy seems to be contributing fact for rabbit health status maintaining.

This study aimed to investigate the interactions between corn particle size (PS) and conditioning temperature (CT) on the performance, carcass traits, intestinal morphology, and immune responses in broilers fed a corn-soybean meal-based diet. A total of 360, one-day-old male broiler chicks (Ross 308) were randomly allocated into six dietary treatments in a 2×3 factorial arrangement, consisting of two corn PS (finely ground with geometric mean diameter (GMD) of 357 µm (PSF) vs. coarsely ground corn with GMD of 737 µm (PSC), and three CT [unconditioned (CTU), conditioned at 75◦C (CT75) and 90◦C (CT90)]. Birds accommodated in 30 pens with five replicates and 12 chicks per each. There was no interaction between corn PS and CT on growth performance and immune response of broilers at any growth phases. However, during the starter (0-10d) period, the average daily weight gain (ADWG) and feed conversion ratio (FCR) of PSF-fed birds were significantly improved compared to those fed PSC (P<0.05). During the starter (0-10d) and grower (11-24d) periods, increasing the conditioning temperature of corn increased the ADWG, while in the starter phase only the CT75 caused a lower FCR (P<0.05). Broilers fed PSF corn showed lowest FCR during the finisher (25-42d) period compared to those fed PSC (P<0.05). Conditioning corn at 75ºC reduced FCR during the finisher (25-42d) period compared to the birds fed CTU and CT90 corn (P<0.05). In whole experimental periods (1-42d), PSF and CT75 treatment increased the ADWG compared to the PSC and CTU (P<0.05). The CT75 treatment improved primary total anti-sheep red blood cell (SRBCs) titer (IgT) and IgM and secondary IgT and IgG responses compared to the other experimental groups (CTU and CT90) (P<0.05). No significant PS × CT interaction was found on Newcastle disease (ND) antibody titer of broiler chickens (P>0.05). Feeding CT75 corn reduced duodenum and jejunum relative length compared to the birds fed diets containing CTU corn. Significant PS×CT interactions (P<0.05) were observed for villus height, villus height to crypt depth, crypt depth, muscle thickness, and absorption surface area of jejunum. The highest carcass yield observed in PSF-CT75-group (P<0.05). In conclusion, the use of finely ground corn (PSF) conditioned at 75℃ (CT75) was beneficial to growth performance, development of the digestive tract, jejunum histomorphometry and the immune responses of broilers.

Consumption of poultry meat is higher than red meat due to easy availability, good taste, low cost and palatability. Significant improvement in meat yield and growth rate of broiler chicken has been brought about with the help of genetic selection of desirable traits. The present study was conducted to comparatively evaluate the chronic effect of domestic and broiler chicken meat consumption on male hypothalamic pituitary gonadal axis, lipid profile and oxidative stress on postnatal male rats. Rats were divided into five groups: control, B1, B2, D1 and D2 groups and were fed with 0.17g and 0.34g of broiler and domestic chicken meat from postnatal day 21 to PND90.The significant elevated body weight and weight gain in B2 group (P<0.01), minor change in B1 and D40 group (P<0.05) were detected. In gonadosomatic index absolute and relative epididymis weight, weight of seminal vesical and Prostate weight was significantly augmented in B2 compared to control and D2. Kidney and liver weight in B1, B2 was markedly elevated and minor change in D2 groups. ROS level in B2 was significantly higher than other experimental groups. Serum level of FSH, LH, testosterone, estradiol and low density lipoprotein was significantly elevated in B2 compared to control and D2. In B2 rats fed with 0.34g broiler meat exhibited a marked decreased seminiferous tubule diameter, epithelial height and increased lumen diameter changes that were more prominent compared to rats fed with 0.34g domestic chicken meat. Conclusively chronic administration of broiler meat induces marked alteration in reproductive system, testicular morphology, sexual hormones and oxidative stress in postnatal Sprague Dawley male rats compared to domestic chicken meat.

Concerns regarding the safety of ethoxyquin (EQ) have gradually increased, highlighting the necessity of identifying safer and more effective antioxidants for use in animal feed. This study investigates the effects of a compound antioxidant (CA) as an alternative to ethoxyquin on feed oxidative stability, growth performance, antioxidant capacity, and intestinal health in broilers. A total of 351 one-day-old Arbor Acres Plus male broilers were randomly assigned to three treatments with nine replicates of 13 birds each. The experimental treatments included: CON group (basal diet), EQ group (basal diet + 200 g/ton EQ at 60% purity), and CA group (basal diet + 200 g/ton compound antioxidant, which comprises 18% butylated hydroxytoluene, 3% citric acid, and 1% tertiary butylhydroquinone). The experiment lasted for 21 days. Compared to the control group, supplementation with CA significantly reduced the acid value, peroxide value, and malondialdehyde content in the feeds after storage. Moreover, CA supplementation significantly decreased feed intake and the feed conversion ratio (FCR) without affecting weight gain of boilers, while also improving liver antioxidant capacity (increased T-AOC and SOD levels), intestinal antioxidant capacity (increased CAT, HO-1, and GPX7 protein expression), and enhancing the duodenal villus height-to-crypt depth ratio and jejunal villus height. Additionally, CA treatment reduced intestinal barrier permeability (decreased diamine oxidase activity and D-lactate levels), potentially by promoting the expression of Occludin, ZO-1, and Mucin2 protein. Furthermore, the addition of CA elevated the protein levels of NF-κB p50 along with its inhibitory factors, IκB and NF-κB p105, in the intestines of broilers, thereby enhancing immune regulatory capacity. This supplementation also led to an increased abundance of beneficial gut microorganisms, including Lactobacillus, Alistipes, Candidatus Arthromitus, and Turicibacter. In comparison to the EQ group, CA supplementation enhanced feed oxidative stability, decreased the FCR, and improved the intestinal morphology, barrier functions, and inflammatory status in broilers. These findings suggest that this compound antioxidant may serve as a healthier and more effective alternative to ethoxyquin.

The rapid expansion of livestock production sector to meet the world population demand is posing a big challenge to environmental sustainability. Plant-based feed additives extracted from food by-products could potentially result in a double outcome: improving animal zootechnical performances and mitigating environmental impacts of meat production chains. This presented study was carried out to assess the environmental impacts of the supplementation of a commercial Citrus extract feed additive (CEFA) in swine and broiler farming. Life cycle assessment (LCA) was applied to assess the impact of manufacturing and distributing 1 bag of 25 kg of CEFA and its use in feed in broiler and swine productions. With regard to CEFA manufacturing and distribution, results showed that the majority of impact came from the production of CEFA ingredients, accounting for 70% impact generated. The remaining 30% effect was divided to transportation to customer (25%), CEFA packaging (3%), CEFA manufacture, and production loss (2%). When enlarging the scope, the use of CEFA in piglet and broiler diets showed improving the measured environmental indicators, compared to such standard systems. Indeed, feed supplemented CEFA have demonstrated in elevating zootechnical performances, hence saving feed consumed. Consequently, that helped reduce environmental issues from animal feed ingredients’ agriculture. To be more specific, the supplementation of 25 kg of CEFA in feed led to a reduction of 6 tons of CO2 emitted along the life cycle of broiler production and 5 tons in the case of fattening pig. 0.7 hectares of land used had been saved as well as, 201 m3 of water (broiler) and 82 m3 (swine) were economized. Environmental performance assessment showed the interest in using this CEFA in swine and broiler diets to mitigate the environmental impacts.

In order to improve the adaptability of broilers to low-temperature environments and their ability to resist acute cold stress (ACS), 240 one-day-old broilers were selected and randomly divided into three groups. The control treatment (CC) was raised at the conventional feeding temperature from 1-43 days (d), the cold stimulation treatments (CS) were kept at 3 °C below the temperature of CC at 1-d intervals for 3 and 6 hours from 15 to 35 d, namely CS3 and CS6, respectively. Then all broilers were kept at 20 °C from 36 to 43 d. ACS was then carried out at 44 d, and the ambient temperature was dropped to 10 °C for 6 hours. The study investigated the production perfor-mance, as well as levels of intestinal barrier genes (including Claudin-1, E-cadherin, Occludin, ZO-1, ZO-2 and Mucin2), secretory IgA in duodenum and jejunum, and immunoglobulins (IgA and IgG) in serum. The results showed that IMCS could increase the daily weight gain and decrease the feed conversion ratio. During the IMCS, the expression levels of intestinal barrier genes were up-regulated and the content of secretory IgA was increased. When IMCS ceased for one week, the level of immunoglobulins in serum stabilized, and the expression levels of Occludin, ZO-2 and Mucin2 still maintained high levels. After ACS, broilers that received IMCS training maintained the high levels of intestinal barrier genes and secretory IgA.

Infectious bursal disease (IBD) is one of the most endemic diseases of commercial poultry in Ethiopia. Vaccination has been practiced as the major means of IBD prevention and control. A study was conducted to determine and compare the immunogenicity of two commercially available IBD vaccines in broiler chicken with maternally derived antibody (MDA). Day-old chickens of 270 were randomly assigned to three groups, group 1 vaccinated with brand 1 vaccine at 7^th and 19^th days and group 2 with brand 2 vaccine at 15^th and 22^nd days while group 3 were kept as control. Six chickens were also randomly selected and bled on day 1 for differential leukocyte count (DLC) and determination of MDA. Representative chickens from each group were bled at 24^th and 42^nd days of age for antibody titration using the indirect ELISA test. DLC scores were determined in the 1^st and 24^th days. The result revealed highly significant differences (P = 0.001) between group 1 and group 2 in DLC at 24^th days of age. Antibody titers against IBD were differed significantly (P = 0.02) at 24^th and 42^nd days of age in broilers vaccinated with brand 1 and brand 2 vaccines. It is concluded that although both brands of vaccine induce an adequate immunological response at the end of the experiment, brand 1 vaccine has shown significantly high antibody titers against the IBDV and DLC than brand 2.

Abstract:Salmonella species (spp) and Escherichia coli (E. coli) are the most common infectious pathogens in poultry. Antimicrobials were given either for the treatment or growth promoters that can increase the possibility of emergence of bacterial resistance towards antimicrobials. The aim of this study was to determine the prevalence of antimicrobial resistant (AMR) Salmonella spp and E. coli isolated from a sample of broiler farms in East Coast Malaysia from 2018-2019. A total of 384 cloacal swabs were collected from broilers farms in Kelantan, Terengganu, and Pahang. The bacteria were isolated and confirmed by bacteriological and serological methods. Following that, confirmed isolates were subjected to antimicrobial susceptibility test. Salmonella spp and E. coli were recovered from the cloacal swabs samples with the overall prevalence of 6.5% and 51.8% respectively. In Kelantan, Terengganu and Pahang, the prevalence of Salmonella spp were 7%, 6.5% and 5.8% respectively, while the prevalence for E. coli were 50%, 48.3% and 58% respectively. Salmonella spp and E. coli displayed resistance towards the following antimicrobials: erythromycin (100% for both pathogens), chloramphenicol (76.2%, 84.5%), tetracycline (62%, 94.6%), ampicillin (47.7%, 87%), sulfamethoxazole/trimethoprim (42.9%, 83.3%), ciprofloxacin (4.8%, 23.8%), nalidixic acid (9.6%, 60.7%), streptomycin (19%,66%), and kanamycin (28.6%,57%), cephalotin (0%, 11%), gentamicin (0%, 20.2%) respectively. No resistance were recorded towards colistin for both pathogens. Multidrug resistance (MDR) was recorded in 82% of Salmonella spp and 100% of E. coli. These findings demonstrate the high prevalence of MDR Salmonella spp. and E. coli in broiler farms in East coast Malaysia. This could be attributed to the excessive use of antimicrobial agents by the poultry farm owners. Enhanced control measures and a strong monitoring system should be urgently implemented to reduce the emergence of antimicrobial resistance that is harmful to public health.

In response to escalating global demand for poultry, the industry grapples with an array of intricate challenges, from enhancing productivity to improving animal welfare and attenuating environmental impacts. This comprehensive review explores the transformative potential of digital phenotyping, an emergent technological innovation at the cusp of dramatically reshaping broiler production. The central aim of this study is to critically examine digital phenotyping as a pivotal solution to these multidimensional industry conundrums. Our investigation spotlights the profound implications of 'digital twins' in the burgeoning field of broiler genomics, where the production of exact digital counterparts of physical entities accelerates genomics research and its practical applications. Further, this review probes into the ongoing advancements in the research and development of a context-sensitive, multimodal digital phenotyping platform, custom-built to monitor broiler health. I critically evaluate this platform's potential in revolutionizing health monitoring, fortifying the resilience of broiler production, and fostering a harmonious balance between productivity and sustainability. Subsequently, the paper provides a rigorous assessment of the unique challenges that may surface during the integration of digital phenotyping within the industry. These span from technical and economic impediments to ethical deliberations, thus offering a comprehensive perspective. The paper concludes by highlighting the game-changing potential of digital phenotyping in the broiler industry and identifying potential future directions for the field, underlining the significance of continued research and development in unlocking digital phenotyping's full potential. In doing so, it charts a course towards a more robust, sustainable, and productive broiler industry. The insights garnered from this study hold substantial value for a broad spectrum of stakeholders in the broiler industry, setting the stage for an imminent technological evolution in poultry production.

Probiotics have emerged as a prominent alternative to antibiotics in antimicrobial-free broiler farming. To assess the effect of the probiotics Sphingomonas sp. Z392 isolated and identified by this this laboratory on broiler growth, we conducted a study to examine the changes in broiler body weight, EPI, intestinal histological structure and gut microbiota. The results showed that supplementation of broiler drinking water with 4 × 105 CFU/mL of Sphingomonas resulted in an increase in the relative abundance of Lactobacillus, Bacteroides, Lachnospiraceae, Aminobacterium, Oribacterium, Christensenellaceae, Faecalibacterium, Barnesiella, Ruminococcus, Parabacteroides, Phascolarctobacterium, Butyricicoccaceae, and Caproiciproducens, which were reported to be positively correlated with the digestion and absorption of broiler chickens. The relative abundance was increased of Odoribacter, Alistipes, Parabacteroides, and Rikenellaceae, which were reported to be negatively correlated with the occurrence of intestinal diseases. The relative abundance was decreased of Campylobacter, Shigella Castellani, Bilophila, Campylobacter, Clostridia, and Anaerotruncus, which were reported positively correlated with the occurrence of intestinal diseases. At the same time, it was increased in the integrity of small intestinal villus morphology, the number of goblet cells in small intestinal epithelial cells, the health of mitochondria in the cytoplasm of jejunal villous epithelial cells, and the number of lysosomes in the cytoplasm of goblet cells in small intestinal epithelium, ileal villous epithelial cells, mitochondria in the cytoplasm of large intestinal villous epithelial cells, the VH/CD of the ileum, digestive, absorption, and defense capabilities. Especially the final weight was increased by 4.33% and the EPI increased by 10.10%. Therefore, the supplementation of broiler drinking water with Sphingomonas generated better economic benefits for the broiler chickens.

A prior investigation revealed that a lack of Zinc (Zn) could hinder the intestinal cell proliferation in broiler chickens; however, the mechanisms responsible for this effect remain unclear. We aimed to investigate the possible mechanisms of dietary Zn deficiency in inhibiting the jejunal cell proliferation of broilers. For this study, a total of 112 chickens (21 d old) were randomly divided into two treatments (n = 7, 8 chickens per replicate cage): control (CON) and Zn deficiency groups. The duration of feeding was 21 d. Chickens in the CON group were provided with a basal diet containing an extra addition of 40 mg Zn/kg in the form of Zn sulfate, whereas chickens in the Zn deficiency group were given the basal diet with no Zn supplementation. The results indicated that, in comparison to the CON, Zn deficiency increased (P < 0.05) duodenal and jejunal crypt depth (CD) of broilers on d 28 and jejunal and ileal CD on d 35, and decreased (P < 0.05) duodenal, jejunal and ileal villus height/crypt depth (VH/CD) on d 28 and jejunal VH, jejunal and ileal villus surface area and VH/CD on d 35. Furthermore, Zn deficiency decreased (P < 0.0001) the amount of proliferating cell nuclear antigen positive cells, and down-regulated (P < 0.01) mRNA or protein expression levels of phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K, phosphorylated serine threonine kinase (AKT), phosphorylated mechanistic target of rapamycin (mTOR), G protein-coupled receptor 39 (GPR39), and extracellular regulated protein kinase, but up-regulated (P < 0.05) mRNA or protein expression levels of P38 mitogen activated protein kinase, c-jun N-terminal kinase (JNK) 1 and JNK2 and phosphorylated Protein Kinase C in the jejunum of broilers on d 42. It was concluded that dietary Zn deficiency inhibited the cell proliferation possibly via GPR39-mediated suppression of PI3K/AKT/mTOR signaling pathway in the jejunum of broilers.

Extensive genomic analyses of Enterococcus cecorum isolates from sepsis outbreaks in broilers suggests a polyphyletic origin likely arising from core genome mutations rather than gene acquisition. This species is normal intestinal flora in avian species with particular isolates associated with osteomyelitis. More recently, the species has been associated with sepsis outbreaks affecting broilers during the first 3 weeks post hatch. Understanding the genetic and management basis of this new phenotype is critical for developing strategies to mitigate this emerging problem. Phylogenomic analyses of 227 genomes suggest that sepsis isolates are polyphyletic and closely related to both commensal and osteomyelitis isolate genomes. Pangenome analyses detect no gene acquisitions that distinguish all sepsis isolates. Core genome SNP analyses identify a number of mutations, affecting protein coding sequence, that are enriched in sepsis isolates. Analysis of the protein substitutions supports mutational origins of sepsis isolates.

Concern for global health security and the environment due to the emergence of antibiotic-resistant bacteria and antibiotic residues in meat and other livestock products has led many countries to restrict the use of antibiotics in animal feed. This experiment was performed to assess the impact of dietary supplementation with a probiotic (Bacillus subtilis) and a postbiotic (Saccharomyces cerevisiae fermentation product) on growth performance, carcass traits, blood haemato-biochemical profile, gut microbiome, gut morphology, and immune response in broilers as an alternative to antimicrobials in poultry production system to minimize the effect on global health security. A total of 324-day-old Ven Cobb 400 broiler chicks were randomly divided into three dietary groups, each containing 12 replicated pens (n = 12), .and each replicate contained nine broiler chickens. The dietary groups consisted of 1) a basal diet without any growth promoting (T1), 2) the basal diet augmented with Bacillus subtilis at 200 g/MT feed (T2), and 3) the basal diet supplemented with Saccharomyces cerevisiae fermentation product at 1.25 kg/MT feed (T3). To calculate body weight gain, all birds and residual feed were weighed on a replicated basis over days 0, 7, 14, 21, 28, 35, and 42; mortality was recorded daily. Each replicate's mortality percentage was calculated and used to adjust BW, ADFI, and FCR calculations at the trial's end. At the end of the trial (42 d), two chickens from each replicate (24 chickens per group) were slaughtered for carcass traits, gut microbiome, and morphology measurements. Blood samples were collected for the haemato-biochemical profile on 35d and antibody titer on 28d and 35d.Feeding with SCFP (T3 group) significantly improved average daily feed intake (ADFI) and average daily gain (ADG) of chickens compared to the T1 (control) and T2 (probiotic) groups from 1 to 14 days of age. FCR was significantly improved (P<0.05) in SCFP-fed birds (T3) relative to the control (T1)over the entire experimental period (1-42 days). Carcass traits and blood haemato-biochemical parameters remained unaffected (P>0.05) by any diets. However, cholesterol levels and concentrations of corticosterone were significantly lower (P<0.05) in SCFP-fed birds (T3) compared to those of the probiotic (T2) and control (T1) groups. Total E. coli, Enterohaemorrhagic E. coli, ESBL-producing Enterobacteriaceae, and Salmonella counts were significantly higher in the T1group compared to T3 and T2 groups (P<0.05) and Salmonella counts were lower in T3 when compared to T2 (P<0.05). However, there was no significant difference in Lactobacillus count among treatment groups. PCR based characterization of ESBL- producing Enterobacteriaceae revealed maximum presence of blaCTX-M-Type (6/15, 40%), followed by blaSHV-Type (5/15, 33.3%) and blaTEM-Type (4/15, 26.6%). No variation in the occurrence pattern of ESBL/beta-lactamase associated genes in the studied ESBL- producing Enterobacteriaceae isolates was observed between the treatment groups. A significant increase in villi height and villi height to crypt depth ratio (VH: CD) (P<0.05) was observed in both T3 and T2 groups. Contrarily, villi widths did not vary across the dietary groups (P>0.05). The control group (T1) displayed a notable deeper in crypts when compared to the T3 and T2 groups (P<0.05). On day 28, the SCFP-fed birds (T3) and those fed the probiotics (T2) exhibited a significant increase (P<0.05) in antibody titers against Newcastle disease virus and Infectious bursal disease virus. Increase in antibody titre against IBDV in birds with the addition of SCFP in the diet was detected for the first time. However, there were no significant differences observed on day 35. The phagocytic activity of neutrophils and lymphocytes in broiler chickens did not show any noticeable variations among the different groups at day 35(P>0.05).It can be concluded that Saccharomyces cerevisiae fermentation product and Bacillus subtilis probiotic could be viable alternatives to antimicrobials in poultry production considering beneficial impacts in broilers fed antibiotic-free diet.

This research is aimed to investigate the effects of Lactoplantibacillus plantarum (L. plantarum) on growth performance, oxidation resistance, immunity, as well as cecal microbiota in broilers. This work classed three hundred and sixty 1-day-old broilers as three groups randomly, including control (CON, basal diet), antibiotic (ANT, 75 mg kg-1 chlortetracycline added into basal diet), or probiotic group (LP, 5×108 CFU kg-1 Lactoplantibacillus plantarum HJLP-1 contained within basal diet). Animal were then fed for 42 days, and each group consisted of 15 broilers for 8 replicates. Compared with CON, L. plantarum supplementation significantly improved the average weight daily gain (AWDG) (P < 0.05) while reducing feed-to-gain ratio over the entire supplemental period (P < 0.05). Birds fed L. plantarum had marked lower serum ammonia and xanthine oxidase levels (P < 0.05) than those in ANT and CON. Significant improvements (P < 0.05) of superoxide dismutase, catalase, serum IgM and IgY contents in broilers fed L. plantarum were also observed when compared those in CON and ANT groups. Both L. plantarum and antibiotics decreased the pro-inflammatory factor IL-1β level significantly (P < 0.05), while only L. plantarum promoted the anti-inflammatory factor IL-10 level dramatically in the serum (P < 0.05) compared with CON. The L. plantarum dramatically (P < 0.05) increased acetic acid and butyric acid concentrations in the cecal contents，when compared to those in CON and ANT. Among the differences revealed by 16S rRNA analysis, L. plantarum markedly improved the community richness of cecal microbiota. At the genus level, butyric acid-producing bacteria Ruminococcus and Lachnospiraceae were found in higher relative abundance in samples of L. plantarum treated birds. In conclusion, dietary L. plantarum supplementation promoted the growth and health of broilers, likely by inducing a shift in broiler gut microbiota toward short-chain fatty acid (SCFA)-producing bacteria. Therefore, L. plantarum has tremendous potential as an alternative for antibiotics in poultry breeding.

Mobility is a vital welfare indicator which may influence broilers’ daily activities. Classical broiler mobility assessment methods are laborious and cannot provide timely insights into their conditions. Here, we proposed a semi-supervised Deep Learning (DL) model, YOLOv5, combined with Deep Sort algorithm conjoined with our newly proposed algorithm, Neo-Deep Sort, for individual broiler mobility tracking. Initially, 1,650 labeled images from five days were employed to train the YOLOv5 model. Through semi-supervised learning (SSL), this narrowly trained model was then used for pseudo-labeling 2,160 images, of which 2,153 were successfully labeled. Thereafter, the YOLOv5 model was fine-tuned on the newly labeled images. Lastly, the trained YOLOv5 and the Neo-Deep Sort algorithm were applied to detect and track 28 broilers in two pens and categorized them in terms of hourly and daily traveled distances and speeds. SSL helped in increasing the YOLOv5 model’s mean Average Precision (mAP), in detecting birds, from 81% to 98%. As compared with the manually measured covered distances of broilers, the combined model provided individual broiler's hourly moved distances with a validation accuracy of about 80%. Eventually, individual and flock level mobilities were quantified while overcoming the occlusion, false and miss detection issues.

In the present study, a numerical model was developed to predict the flow pattern inside a broiler building. The model intends to predict the velocities fields inside the domain and ammonia (NH3) emitted or released by litter from poultry housing. The numerical model developed in Computational Fluid Dynamics (CFD) commercial code, intends to represent a commercial broiler building, and intends to simulate the 3D and heat transfer, in steady state flow. The evaporative cooling pads were also included in the model. The validation of the model was based in experimental measurements obtained in previous studies. The simulations were focused on Summer, Winter and also Mid-Season situation. The numerical results of NH3 concentration were compared with the experimental measurements, and a quite good agreement was verified. The numerical results allowed the characterization of: the inside flow pattern developed for the summer and winter situation; the inside NH3 distribution, and the velocity field distribution inside the broiler building. It was found that NH3 concentration increases along the tunnel, especially in low flow rate imposed from the exhaust fan. Also, it was verified that the low velocities inside domain are no sufficient to remove the gaseous pollutants.

Brazil chicken production is around 13 million tons and about a third is exported to over 150 countries, placing Brazil as the world largest chicken meat producer, and therefore it is crucial to follow the legislation of all importer markets. This study conducted a survey by chance in 45 meat industries able to export. Therefore, 2580 chicken meat samples were collected and submitted to 11 analyte extraction and chromatographic verification of compliance in an accredited laboratory. Ten chemical residues (amoxicillin, bacitracin, colistin, dinitolmide + zoalene, spectinomycin, roxarsone, tiamulin, tylosin, trenbolone acetate and virginiamycin) were investigated in chicken meat and one (halofuginone hydrobromide) in chicken liver. The results showed that no compound exceeded the maximum residue limits established by seven legislations. All residue concentrations found were below the method quantification limit, thereby confirming the capability of Brazilian chicken meat industries in complying to foreign markets.

Over the last decade, there has been a growing interest in the use of a wide range of phytoadditives to counteract the harmful effects of heat stress in poultry. Willow (Salix spp.) is a tree with a long history. Among various forms, willow bark is an important natural source of salicin, β-O-glucoside of saligenin, but also of polyphenols (flavonoids and condensed tannins) with antioxidant, antimicrobial and anti-inflammatory activity. In light of this, the current review presents some literature data aiming to: (1) describe the relationship between heat stress and oxidative stress in broilers, (2) present or summarize literature data on the chemical composition of Salix species, (3) summarize the mechanisms of action of willow bark in heat-stressed broilers, (4) present different biological effects of the extract of Salix species in different experimental models.

United States is the largest producer and the second largest exporter of broiler meat in the world. In the U.S, broiler production is largely converting to antibiotic-free programs which has caused an increase in morbidity and mortality within broiler farms. Escherichia coli and Clostridium perfringens are two important pathogenic bacteria readily found in the broiler environment and result in annual billion-dollar losses from colibacillosis, gangrenous dermatitis, and necrotic enteritis. Broiler industry is in search of non-antibiotic alternatives including novel vaccines, prebiotics, probiotics, and housing management strategies to mitigate production losses due to these diseases. This review provides an overview of the broiler industry and antibiotic free production, current challenges, and emerging research on antibiotic alternatives to reduce pathogenic microbial presence and improve bird health.

The black soldier fly larvae meal has attracted attention as a sustainable alternative protein ingredient in poultry feed. In the present study, we sought to determine the effect of black soldier fly larvae on the growth performance of broilers as replacement to fishmeal. Forty (40) one day old broiler chicks were randomly selected and distributed in 4 replicates. The Black soldier fly larvae were formulated and added to broiler’s marsh as replacement to fishmeal. Birds were fed on four experimental diets formulated as follows 15% black soldier fly (BSF15), 20% (BSF20) and 25% (BSF25) corresponding to dietary BSF inclusion levels of 150 g/kg, 200 g/kg and 250 g/ kg, respectively and the control diet (BSF0) contained 20% of fishmeal (FM) as protein sources (250 g/kg). Feed and water were provided ad libitum. Proximate analysis showed that BSFLM contained comparable nutrient values to fishmeal. The highest average weight gain was achieved when birds were provided diet with 25% BSFLM. Based on this study, it can be concluded that black soldier fly larvae meal represents an alternative source of animal protein to replace fishmeal in broiler chicken diet in their diet without adverse effect on growth performance and consumer preferance.

The present study was conducted to evaluate encapsulated essential oils as an alternative anticoccidial in coccidiosis vaccine challenged broiler chickens. A total of 600 day-old male broiler chicks were provided with no-added corn-soybean meal-based control diet or diets that contained either salinomycin or EO at 60 and 120 mg per kg of diet. On day 21, half of the control groups were orally challenged with a coccidiosis vaccine at 25 times higher than the recommended vaccine dose. During 22 to 28 days (i.e., one-week post coccidiosis vaccine challenge), the challenged chickens had decrease (P < 0.05) in body weight gain and feed intake but increase in feed conversion ratio compared with the non-challenged, naïve control chickens. However, dietary EO significantly counteracted (P < 0.05) coccidiosis vaccine-induced depression in body weight gain and feed intake. Increasing dietary EO linearly decreased (P < 0.05) the concentrations of the volatile fatty acids. Dietary SAL and EO affected gut morphology in chickens at 20 days posthatch. Increasing dietary EO linearly (P = 0.073) increased serum catalase activity. Collectively, our study shows that dietary EO increased coccidiosis vaccine-induced growth depression and altered gut physiology in broiler chickens.

: Organic poultry need high-quality proteins in their diet. The EU’s organic regulation forbids synthetic amino acids; therefore, soybean, with its balanced essential amino acid content, has become the most used protein source, though much of it is imported from non-EU countries. Soybean, however, has some important problems related to sustainability and crop competition; therefore, it must be substituted with a high-protein-value alternative such as insect meal. In this study, 900 Aviagen Savanna broilers were reared using three different organic diets. The diets used the following as protein feed material: soybean only (S100), 50% black soldier fly larvae meal (BSL) and 50% soybean (BSL50), and 100% BSL only (BSL100). Broiler performance, welfare, and fatty acids (FA) in the thigh and breast were analyzed. BSL50 and BSL100 negatively affected growth performance, while BSL100 worsened all of the market-related measures of performance. Meat quality was worse in BSL50 and BSL100, with a significant increase in saturated FA (SFA) and a corresponding decrease in polyunsaturated FA (PUFA). Among SFA, lauric acid (C12:0) more notably increased. The increase in SFA represents a negative aspect of BSL meal inclusion, namely the production of lauric acid; however, this trend could have a beneficial effect, which will be more deeply explored with regard to its impact on animal and human health.

This trial was carried out to find out the effects of the parent flocks and the hatching time of broiler chickens on the production traits and bacteriota development of animals. Two times 730 hatching eggs were collected from two different parent flocks with age of 22-23 and 65-66 weeks. In the hatchery both groups were divided into two subgroups, when the day-old chickens were separated according to their hatching time. A feeding trial was carried out afterwards, using the 4 treatments in 6 replicate floor pens, feeding commercial starter, grower, and finisher diets, that contained all the nutrients according to the breeder’s recommendations. The day-old chickens of the parent older flock and those hatched later were heavier and this advantage of the birds remained until end of the production period. The different age and origin of parent flocks failed to modify the microbiological parameters of the chicken’s ceca. However, the hatching time significantly influenced the different bacteriota diversity indices. The late hatched chickens showed higher Bacteroidetes and Actinobacteria and lower Firmicutes abundances at day 11. These treatments resulted differences in the main families, Ruminococcaceae, Lactobacillaceae, Bacteroidaceae. These differences could not be found at day 39.

A comparative efficacy of apathogenic genotype I (V4) and lentogenic genotype II (LaSota) strains of live Newcastle disease virus (NDV) vaccines was done following vaccination with pathogen-associated molecular pattern (PAMP) H9N2 avian influenza vaccine and challenge with velogenic NDV genotype VII.1.1 (vNDV-VII.1.1). Eight groups (Gs) of day-old chicks were used (n=25). Groups 1-4 received a single dose of PAMP-H9N2 subcutaneously, while Gs (1, 5) and (2, 6) received eye drops of V4 and LaSota respectively as twice doses. All Gs except 4 and 8 were intramuscularly challenged with vNDV-VII.1.1 at 28th days of age. No signs were detected in Gs 1, 5, 4, and 8. The mortality rates were 0% in Gs 1, 4, 5, and 8; 40% in G2; 46.66% in G6; and 100% in Gs 3 and 7. Lesions were recorded as minimal in Gs 1 and 5, but mild to moderate in Gs 2 and 6. The lowest significant viral shedding was detected in Gs 1, 2, and 5. In conclusion, two successive vaccinations of broilers with a live V4 NDV vaccine provided a higher protection against vNDV-VII.1.1 challenge than LaSota. Besides, PAMP-H9N2 with live NDV vaccines induced more protection than live vaccine alone.

Avian necrotic enteritis is an enteric disease of broiler chickens caused by certain pathogenic strains of Clostridium perfringens in combination with predisposing factors. A vaccine offering complete protection against the disease has not yet been commercialized. In a previous study, we produced five recombinant proteins predicted to be surface-exposed and unique to necrotic enteritis-causing C. perfringens and the immunogenicity of these potential vaccine candidates was assessed in broiler chickens. In the current work, the relative contribution of the antibodies raised by these putative antigens to protect broiler chickens was evaluated using an experimental necrotic enteritis induction model. Additionally, the link between the immune response elicited and the gut microbiota profiles in immunized birds subjected to infection with virulent C. perfringens was studied. ELISA results showed that the IgY antibody titers in vaccinated birds on days 21 and 33 were significantly higher than those on days 7 and 14 and those in birds receiving the adjuvant alone, while the relative contribution of the specific immunity attributed to these antibodies could not be precisely determined using this experimental NE induction model. Besides, 16S rRNA gene amplicon sequencing showed that immunization of birds with recombinant proteins had a low impact on the chicken caecal microbiota.

Food authorities aim to safeguard our food. This requires sensitive analyses to guarantee detection of both banned and regulated substances at low concentrations. At the same time, broad screening methods are needed to identify new emerging risks. For this purpose effect-based bioassays combined with mass spectrometric analyses offer an advantage. During the regular monitoring of dioxins in agricultural products, a discrepancy was observed between the results of the DR CALUX (Dioxin-Responsive Chemical Activated Luciferase gene Expression) bioassay and the confirmatory gas chromatographic high resolution mass spectrometric (GC-HRMS) analysis in egg and broiler fat samples. The response in the bioassay was high, suggesting a clear exceedance of the maximum limits of dioxins in these samples, yet regulated dioxins or dl-PCBs were not detected by GC/HRMS analysis . Ultimately, a broad screening analysis using GC-HRMS resulted in the identification of 2,3,7,8-tetrabromo-dibenzofuran (2,3,7,8-TBDF) in both egg and broiler fat. To investigate the potential; source of this brominated furan contaminant, different samples were analysed: bedding material, poultry feed, feed additives (choline chloride and L-lysine) and seaweed. The poultry feed and feed additives all contained 2,3,7,8-TBDF. Using a feed to food converter, it became clear that the poultry feed was probably the source of 2,3,7,8-TBDF in broilers and eggs through a feed additive like L-lysine or choline chloride. This study underlines the importance of using a combination of effect based screening assays with sensitive analytical methods to detect potential new and emerging risks.

This study evaluated gas mixtures of carbon dioxide (CO2) associated with nitrogen (N2) as al-ternatives to the use of CO2 in two phases to improve the welfare of broiler chickens at slaugh-ter. Broilers were exposed to one of three treatments: 40C90C (1st phase: <40% CO2 for 2 min; 2nd phase: >90% CO2 and <2% O2 for 2 min, n=92), 40C60N (40% CO2, 60% N2 and <2% O2 for 4 min, n=79), or 20C80N (20% CO2, 80% N2 and <2% O2 for 4 min, n=72). The time to onset of loss of consciousness (LOC) and death was assessed by brain activity (EEG) and behaviour. Behaviour also allowed characterisation of the aversive response to the treatments. Exposure to 40C60N and 20C80N induced LOC faster (19 s [14 – 30 s] and 21 s [16 – 37 s], respectively) but also with less inter-individual variability compared to 40C90C (53 s [26 – 156 s], P < 0.001) and birds took less time to die (40C60N: 64 s [43 – 108 s]; 20C80N: 70 s [45 – 88 s]; 40C90C: 177 s [89 – 212 s], P < 0.001). The 40C90C birds not only experienced more aversion during induction to LOC but are at risk of remaining conscious when the CO2 concentration is increased in the 2nd phase. From an animal welfare point of view, 40C60N provided the highest welfare, followed by 20C80N and 40C90C.