Poultry, Volume 2, Issue 3 (September 2023) – 7 articles

The production of soybean meal (SBM) has a substantial impact on the environment and reducing its inclusion in poultry diets by using alternative protein sources, such as insect meal, is an important challenge for nutritionists. This study aimed to compare the productive performance of broiler chickens fed one of two isonitrogenic (195 g/kg CP) and isocaloric (12.91 MJ/kg) diets. The first diet contained SBM as the main protein source, whereas SBM was completely replaced by defatted meal from Black Soldier Fly larvae (Hermetia illucens L.; BSFL) in the second diet. Compared to the BSFL diet, the final body weight (BW) and weight gain (WG) of birds fed the SBM diet was ~17% greater and feed was utilised 19% more efficiently (p < 0.05). The differences in WG and FCR were supported by improved energy metabolism metrics, fat digestibility and digestibility of acid detergent fibres (ADFD) (p < 0.05). The present study shows that a complete replacement of dietary SBM with BSFL meal must be achieved with care, ensuring that all other factors (e.g., insect processing technology, feed additive supplementation, non-protein nitrogen accounting, mineral balance, fatty acid profile, amino acid supplementation) have been considered. Full article

Food safety is a major concern for commercial poultry producers and consumers. Currently, there is also pressure from retailers and legislators to increase the space per hen in cages. Five different density treatments consisting of six (208 in²/bird), nine (139 in²/bird), twelve (104 in²/bird), fifteen (83 in²/bird), and eighteen birds (69 in²/bird) per cage were examined in colony cage environments. Microbiological tests were performed at 39, 55, and 68 weeks of age. The populations of total aerobic bacteria; E. coli/coliform; Enterobacteriaceae; and yeasts and molds from an eggshell rinse, egg content, and cloacal swabs were enumerated. The prevalence of Salmonella spp. in these samples was also monitored. Overall, no bacteria were detected in any of the egg content, and there were no differences (p > 0.05) between treatments for the shell rinse. Stocking density did not influence the eggshell microbiota of the hens. Hens housed at 104 in² per hen showed higher levels of total aerobic bacterial counts from the cloaca compared to hens at 208 in² and 69 in² per hen. Hens housed at 139 in² per hen had the highest level of cloacal molds. This research demonstrates that stocking density does not influence eggshell microbiota or Salmonella contamination of the eggshell or cloaca, thereby indicating that allowing more space per hen will not positively or negatively affect the prevalence or concentration of foodborne pathogen-associated bacteria in or on the eggs. Full article

In the past decade, the withdrawal of antibiotics used as growth promoters (AGP) has increased some poultry industry challenges, such as the rise of intestinal diseases. Experts advocate that AGPs improve performance due to the modulation of the intestinal microbiota, with resulting anti-inflammatory effects. However, the impact and interactions of AGPs with the host intestinal immune system are still unknown, which represents issues in developing effective alternatives for AGPs. Therefore, this study was aimed at better understanding the potential mechanism of action of bacitracin used as AGP and its impacts on the intestinal immune system. Ninety day-of-hatch chickens were randomly assigned to two treatments with three repetitions of fifteen birds, a control (CNT) group with a corn/soybean meal standard diet, and a control diet supplemented with 50 g/ton of feed of bacitracin (BMD). The cytokines’ and chemokines’ production (IFN-α, IFN-γ, IL-16, IL-10, IL-21, IL-6, M-CSF, MIP-3α, MIP-1β, VEGF and CCL-5) were assessed in the jejunum and ileum at 14, 21, 28 and 36 days of age by using a chicken-specific cytokine/chemokine peptide ELISA array. Broilers with BMD supplementation were found to have a lower production of IL-16, IFN-γ, M-CSF, IL-21, MIP-1β and VEGF in the jejunum at 14 d. However, from 21 through 36 days, the effect of BMD on cytokine production in the jejunum was negligible except for CCL-5, which was reduced at D36. In the ileum, BMD effects on the cytokine profile started at 28 d, when BMD-supplemented broilers showed a reduced IL-6 production level. At day 36, BMD reduced IL-16 and MIP-3α production but increased VEGF concentration in the ileum tissue. The present study demonstrated that the use of bacitracin as an AGP modulates the small intestine immune system, especially in the first phase of the broiler’s life (up to 14 days). Moreover, BMD anti-inflammatory effects include not only innate immunity but also seemed to influence the development of the adaptive immune response as seen by the decreased production of IL-21 and IL-16. These results demonstrate that a commonly used AGP in broiler feed had a local anti-inflammatory effect. Full article

Background: The poultry industry in India, estimated to be worth about one trillion INR, was severely affected by the COVID-19 pandemic. This study was conducted in Gujarat, India to unpack the processes through which COVID-19-related factors affected the poultry production and distribution network and explore the impacts on the relevant actors. Methods: An exploratory qualitative study was conducted among 34 poultry stakeholders using semi-structured interviews. The data were thematically analyzed by adopting an interpretative phenomenological approach. Results: Convincing evidence emerged that the lockdown and the pandemic significantly impacted the production, distribution, and consumption of poultry products. Movement restrictions during the first lockdown disrupted the supply of inputs and the distribution of poultry and poultry products. Between March and June 2020, rumors contributed to a substantial decrease in the consumption of poultry products. Consumption picked up following the reopening after the lockdown and the prices and availability of poultry products. The profits, however, failed to compensate for the losses that had been incurred. Conclusions: The experience and impacts of the first COVID-19 lockdown on the poultry industry unraveled several short- and medium-term challenges in the poultry sector in India that need to be addressed to make it more resilient to similar shocks. Full article

The adoption of methods detecting intestinal permeability in poultry has been slow due to the lack of urine availability in avian species. The objective of this study was to examine intestinal permeability assays in broilers using serum. Fluorescein isothiocyanate-dextran (FITC-D) and lactulose/mannitol/sucralose (LMS), indigestible sugars, were used to detect intestinal permeability across two fed states (fed or fasted) and four sugar treatments (Control, FITC-D, LMS, or FITC-D+LMS). Broilers housed in pens were assigned one of eight treatments and sampled on 14, 28, and 42 days of age. Data were analyzed using PROC Glimmix for fed state, sugar treatment, age, and all interactions. Serum lactulose and FITC-D increased in fasted compared to fed birds (p < 0.006), whereas mannitol increased in fed compared to fasted birds (p < 0.001). Serum lactulose and FITC-D decreased on day 28 compared to other timepoints (p < 0.003). Serum FITC-D only had a significant sugar by fed state interaction (p < 0.05) with elevated concentrations in fasted and fed birds that received FITC-D. Serum lactulose was significant for all interactions with elevated concentrations in broilers provided lactulose and fasted (p < 0.001). The ability to detect a three-way interaction with serum lactulose suggests an increased sensitivity; however, additional studies are needed. Full article

Infectious bronchitis virus (IBV) is an avian coronavirus (CoV) that belongs to the genus Gammacoronavirus and has been listed as an important disease by the World Organization for Animal Health (WOAH). It causes highly contagious respiratory, reproductive, and renal diseases in commercial poultry farms. Multiple IBV serotypes and genotypes have been identified in many countries and many detected variants do not provide cross-protection against infection, resulting in repeated outbreaks and significant economic losses worldwide. In addition, the high genetic mutations and recombination events in the prominent genomic regions of IBV, particularly in the spike glycoprotein (S) and nucleocapsid (N) proteins, are directly involved in the evolutionary processes of IBV and lead to increased pathogenicity and tissue tropism. The characterization of the different genotypes and the relationship between the structure, function, post-translational modifications (PTMs), and structural motifs will elucidate the mechanisms that promote replication and pathogenicity and affect the host’s immune response during infection. In this review, we discuss the molecular features of various IBV genes and proteins that contribute to the infection process. We also highlight the common PTMs and structural motifs that occur during protein synthesis and are essential components of IBV ecology. Full article

Influenza A viruses (IAVs) belonging to the goose/Guangdong (Gs/GD)-lineage H5Nx remain a major concern for the global poultry industry, wildlife, and humans. The hemagglutinin (HA) protein is the dominant antigenic epitope carrier within IAV, which in turn triggers substantial immunogenic responses in the infected host. The current study describes the development and validation of a highly sensitive competitive H5 ELISA (cELISA) based on a novel monoclonal antibody developed in mice immunized with inactivated virus H5N1 (A/Turkey/ON/6213/1966). The cELISA is capable of detecting the H5 antibody response to a wider range of H5-subtype viruses belonging to both North American and Eurasia lineages, including the Gs/GD H5Nx from clade 2.3.4.4b that is currently causing the highly pathogenic avian influenza outbreaks in Eurasia, Africa, and Latin and North America. The developed H5 cELISA provides a specific, sensitive, and species-independent serological assay for the rapid detection of H5 antibodies. The assay is more robust and more sensitive than the hemagglutination inhibition assay, which is the “Gold standard”. The assay can be used in serological diagnosis, serosurveillance, and vaccine monitoring of serum samples collected from different species of animals. Full article