Due to the increasing demand for antibiotic-free livestock products from the consumer side and the ban on the use of antibiotic growth promoters, the poultry feed industry is increasingly interested in developing more alternatives to cope with this problem. Organic acids (butyric acid) have many beneficial effects on poultry health, performance, and egg quality when used in their diet, thus they can be considered for the replacement of antibiotics in livestock production systems. Butyric acid is most efficacious against pathogenic bacteria such as Salmonella spp. and Escherichia coli, and stimulates the population of beneficial gut bacteria. It is a primary energy source for colonocytes and augments the differentiation and maturation of the intestinal cells. Collectively, butyric acid should be considered as an alternative to antibiotic growth promoters, because it reduces pathogenic bacteria and their toxins, enhancing gut health thereby increasing nutrient digestibility, thus leading to improved growth performance and immunity among birds. The possible pathways and mechanisms through which butyric acid enhances gut health and production performance are discussed in this review. Detailed information about the use of butyric acid in poultry and its possible benefits under different conditions are also provided, and the impacts of butyric acid on egg quality and osteoporosis are noted.

The Turkish poultry industry has rapidly developed in the last decade. Viral pathogens continue to threaten the industry, causing economic losses worldwide, including Turkey. At present, infectious bronchitis and infectious laryngotracheitis are major challenges, as are, to a lesser extent, avian metapneumovirus, infectious bursal disease, Marek's disease and chicken infectious anaemia. The prevalence and severity of these diseases in Turkish chickens varies depending on environmental and management factors, vaccination strategies and biosecurity measures. In Turkey, infectious bronchitis virus, including vaccine and field strains, were detected in 83.6% (41/49) and 64.2% (9/14) vaccinated broiler and layer flocks, respectively. Virulent and vaccine strains of infectious bursal disease virus were found in 83.5% (1548/1855) of excised bursa Fabricius from vaccinated broilers. Virulent Marek's disease virus was found in 19.93% (120/620) of spleens from vaccinated chickens. Infectious laryngotracheitis virus in commercial poultry and Newcastle disease in backyard chickens have been detected. To date, Newcastle disease and avian influenza virus have not been reported in commercial poultry. Avian metapneumovirus was found in 7.2% (8/110) of the broiler samples. Antibodies to gyrovirus and avian leukosis virus have been detected. Commercial vaccines, such as attenuated, inactivated and vectored vaccines, are being used for prevention and control of viral poultry diseases in Turkey. This review summarises the available information on viral poultry diseases in Turkey. It highlights the need to strengthen surveillance and reporting for diseases and addresses the vaccination practices used in Turkish poultry industry. The future prospects of vaccination and need to empower diagnostic capacity in controlling viral poultry diseases are discussed. The information presented here is aimed at improving research, prevention, and control of poultry diseases for researchers, veterinarians, policy makers and other professions related to poultry industry.

Laser-induced breakdown spectroscopy has been exploited to investigate the laser-produced lead plasma with and without external magnetic field. Plasma on the lead surface was generated by focusing a beam of a Nd:YAG laser (532 nm). An external magnetic field was applied across the laser-produced plasma; its value was varied from 0.3 to 0.7 T and the time-integrated spectra were captured at different time delays. Maximum enhancement in the neutral and ionic line intensities have been observed at 130 mJ laser energy. The neutral line of Pb at 368.34 nm reveals an enhancement factor of nearly 1.3, 1.6, and 2.3 at 0.3, 0.5, and 0.7 T, whereas the Pb ionic line at 424.49 nm shows enhancement factor of approximately 2.8 and 4.2 at 0.3 and 0.7 T. The magnetic field effects on various plasma parameters such as plasma temperature, electron number density, and emission line intensities have also been investigated. The plasma parameter “β” is found to be <1 in all the experimental conditions which signifies that the enhancement in the signal intensity is due to the plasma confinement. The increase in the emission signal intensity, number density as well as plasma temperature is observed with increasing laser energy and magnetic field. The spatial and temporal behavior reveals that the plasma temperature and electron number density decrease slowly in the applied magnetic field due to the deceleration of the plasma plume. The optimized conditions for the maximum plasma confinement and the emission intensity enhancement are observed at 130 mJ laser energy at 0.7 T magnetic field.

Royal Jelly (RJ) is product from bees that is used to feed larvae in the hive as well as a main nutritional source for the queen honey bee. It has various important biological activities including as an antioxidant, immunomodulatory, anti-inflammatory, antimicrobial, cholesterol-lowering, and growth promoter activities and has the ability for inhibition of certain enzymatic degradation. It can be used for the improvement of growth performance, gut health and quality and safety of animal products in poultry due to its antioxidant and immune modulating properties. The antioxidant activity of RJ is mainly due to the presence of polyphenolic compounds. It is an excellent source of B and C vitamins and folic acid. The mineral profile of RJ is useful as it contains major macro and micro minerals. Studies conducted on supplementation with RJ in poultry diets have shown a significant increase in body weight, egg production, and immune levels and is especially useful in organic production. Supplementation of RJ at the level of 10 and 15 mg/kg in layer diets positively influenced egg weight (by 5.0% and 4.8% respectively), egg production (10.5% and 11.0% respectively), weight gain of hens (7.0% and 6.5% respectively) and yolk pigmentation (9.5% and 9.7% respectively). Total leukocyte and erythrocyte counts in the diet containing 200 mg/kg RJ were significantly higher than the diet contained 100 mg/kg or the unsupplemented control group. However, the heterophil/lymphocyte ratio and heterophil percent were reduced in RJ-fed groups. Supplementing poultry diets with RJ offers an opportunity to maximise profit from safe and high quality poultry production.

Cinnamon is a common spice obtained from the bark of the cinnamon tree (Cinnamomum zeylanicum). It has been used for culinary, as well as medicinal, purposes since ancient times in various countries. Apart from substantial amounts of several nutrients, including carbohydrates, proteins, choline, vitamins (A, K, C, B3), and minerals, several biological active compounds are present in the extract of oil, which contribute to immunomodulatory, antioxidant, antiviral, lowering blood cholesterol, antimicrobial, lipid-lowering, antihypertension, anti-inflammatory, antitumor, gastroprotective, antidiabetic, neuroprotective and blood purifying properties. Cinnamon roots serve as a hepatic stimulant by improving bile production, eliminating toxins, restoring electrolyte balance and regulating hydration and can be used for enhancing digestion. In addition, nutritional properties of cinnamon powder include positive effects regarding growth, digestion, enhanced activity of gut microflora, improvement of immune response, as well as improved feed efficiency and health improvement of poultry birds. Recently, research focus has been directed towards supplementing broiler diets with cinnamon powder as a phytobiotic in order to replace synthetic growth promoters. After reviewing the literature, it was found that the research at the molecular level to elucidate the mechanisms behind the potential of cinnamon as a feed additive in poultry is limited, despite its promising impacts. Furthermore, supplementation doses vary significantly, i.e., from 0.02 to 7%. So, the aim of this review was to compile the published research related to cinnamon. Hence explore its beneficial properties, find out its optimal dosage for uses by veterinarians, researchers, and nutritionists, as well as its potential to use as a natural feed additive to replace the synthetic antibiotic growth promoters in poultry feed.

Dendritic cells (DC) are central regulators of immune responses and professional antigen-presenting cells (APCs) with the unique ability to induce both innate immune responses and a highly specific acquired immunity. DC communicates through chemical and mechanical signals in the initiation and maintenance of immune responses. DC forms immunological synapses with T-cells thus pulling T-cells strings and leading to activation of T-cells. Owing to their properties, DC are often called ‘nature's adjuvants’ and thus have become an important component of any vaccination strategy. Coccidiosis is a major intestinal disease caused by Eimeria spp., affecting economically valuable livestock animals such as chickens and turkeys. Economic losses are associated with decreased productivity in afflicted poultry. Vaccination strategies involving DC have been developed owing to the special properties of these cells in coordinating innate and adaptive immune responses. Vaccination of chickens with exosomes isolated from DC containing parasite antigens (Ags) represents a promising alternative strategy to control avian coccidiosis. In recent years, emergence of new chicken DC has opened a new horizon for the development of new vaccines and DC derived vaccine could be a possible strategy to control coccidiosis in field. This review summarises the current state of knowledge of DC and their specific functions in immunity against avian coccidiosis.

Mast cells (MCs) are granulated cells of haematopoietic lineage and constitute a major sensory arm of the immune system. MCs dually guard hosts and regulate immune responses against invading pathogens. This property of the MCs is attributed to their adaptability to detect stress signals and pathogens, and the production of signal specific mediators to engage immune cells for clearance of infectious agents. Pathogen-specific signals establish basis for the initiation of adoptive immune responses. These immune regulatory roles of MCs have opened avenues to engage different MCs activators which culminate in effective passive immunisation. The molecular mechanisms and dynamics of functionalities of MCs in host defences have been extensively characterised in mammals and rodents, and research on MCs in avian species is emerging. This review surveys the development, morphology and distribution of MCs in different tissues of the poultry and highlight areas that can be exploited for disease control and prevention.

Newcastle disease virus (NDV) was first reported in 1926. Since then, the NDV has been prevalent in domestic and wild birds representing a diverse and continually evolving group of viruses, consisting one genotype for class I NDV isolates and eighteen genotypes for class II NDV isolates. The emergence of new virulent genotypes from global epizootics and the year-to-year changes observed in the genomic sequence of NDV of low and high virulence implies that distinct genotypes of NDV are simultaneously evolving at different geographic locations across the globe. This vast genomic diversity may be favoured by the large variety of avian species susceptible to NDV infection and by the availability of highly mobile wild bird reservoirs. In certain countries such as Pakistan, the viruses of sub-genotype VIIi have replaced NDV isolates of genotype XIIIa, which were commonly isolated in 2009-2011, and have become the predominant sub-genotype causing ND outbreaks since 2012, suggesting the existence of a fifth panzootic. The genomic diversity of NDV increases the possibility of diagnostic failures, resulting in unidentified infections. Therefore, continuous monitoring of viral evolution and periodic updates of vaccine seed strains are warranted to achieve efficient control and eradication of ND. This review reports on the emergence and evolution of ND viruses and vaccination strategy in Pakistan.

Dendritic cells (DCs) are antigen-presenting cells (APCs) with the unique ability to induce both innate immune responses and a highly specific acquired immunity. DCs are crucial to induce immunity, and their maturation and functions are influenced by microbial and environmental stimuli. Chicken DCs are composed of several subtypes including bursal secretory dendritic cells (BSDCs), follicular dendritic cells (FDCs), and thymic dendritic cells (TDCs). DC maturation depends on the nature of the perturbation and permits unique and efficient immune responses for each pathogen. DCs differentially recognise the viruses, bacteria, parasite and fungi and specifically regulate the immune response. Dendritic cells (DCs) are ‘nature's adjuvants’ and, as such represent an essential component of any vaccination strategy. The understanding of DC regulatory mechanisms opens a new horizon for the development of new vaccines and their targeting with the vaccination for elicitation of better immunity levels. The following review summarises the current state of knowledge of DCs and their specific functions during host pathogens interaction.

Every year the growth of the poultry industry is severely threatened by a number of infectious viral, bacterial and parasitic diseases. There are a number of vaccines to control these diseases including inactivated virus vaccines, attenuated virus vaccines, live virus vaccines, and subunit vaccines, but they are often relatively expensive and require cold storage and trained people to administer them, especially in developing countries. Plant-based vaccines provide a better option to control these diseases in low profit margin poultry industry. Still there are some challenges in the field of plant-based, so called ‘green’ vaccines. Injection-based oral priming is a big challenge for commercialisation of green vaccines so, new techniques are needed in the field of plant-based vaccine to pass these barriers for commercialisation. This discusses the potential for plant-based vaccines and whether they are good option to control poultry diseases.