Emergence of a genotype I lineage 1 variant avian infectious bronchitis virus in Assam, India

Background: Infectious bronchitis (IB) is an acute and highly contagious viral disease of poultry affecting chicken of all ages. The causative agent IB virus (IBV) is a Gammacoronavirus within the family Coronaviridae. Viral genetic mutations and recombination events particularly in the spike protein (S1) of IBV constantly give rise to emerging IBV variants. Vaccination is considered as the most reliable approach for IBV control, but current vaccines have been found to be ineffective due to constant emergence of new variant viruses. Objective(s): The objective of our study was to detect IBV genotypes prevalent in Assam, India. Material(s) and Method(s): Oro-pharyngeal swabs and tissue samples from unvaccinated broiler chickens showing respiratory symptoms were tested using RT-PCR targeting the N gene of IBV. The virus was isolated from infected swab/tissue samples in 9 days old specific pathogen free embryonated chicken eggs through allantoic cavity route. Phylogenetic studies were done based on the S1 gene of IBV. Results and Conclusion(s): Clinically, the birds showed gasping and tracheal rales. Necropsy revealed distended ureters. Virus was isolated and identified by curling and dwarfing of the dead embryos and further confirmed by RT-PCR. Positive PCR amplicons were sequenced and phylogenetic analysis clustered the IBV isolate from Assam with genotype I lineage 1 IBV prototype sequence belonging to Beaudette and Mass 41 strains but the isolate exhibited a relatively high degree of sequence divergence with reference strains. Our findings suggest that the IBV isolate might have emerged from recombination with the local circulating virus or vaccine strains. This will have important implications for IB prevention strategies.

Partial replacement of maize with cassava root-moringa leaf and vegetable oil concentrates in broiler finisher diets

Context. Roots and leaves have potential as feed ingredients for poultry, but antinutritional factors (ANFs), high fibre and low energy may limit their efficient utilisation. There is need to improve processing methods and diet formulation for maximum utilisation of these readily available resources and reduce feed cost. Aim. To investigate the replacement of maize with cassava root, moringa leaf meal and vegetable oil blend in finisher broiler diets. Methods. In total, 160 male broiler chickens aged 30 days were weighed and allotted randomly to 20 deep litter pens containing eight birds of similar individual weight (1500 g +/- 16.11). Four broiler finisher iso-energetic and isonitrogenous diets were formulated for the experiment. Diet 1 was based on maize and in Diets 2, 3 and 4, 15%, 30% and 45% of maize was replaced respectively, by a concentrate of cassava root meal, moringa leaf meal and vegetable oil combination (CMOC). Each diet was given to five pens in a completely randomised design for a period of 12 days. Key results. There were no significant differences in the growth parameters of birds among treatments. Except for drumsticks of birds on the 30% CMOC diet, there were no significant effects of diet on carcass components or digestive organ weights (P > 0.05). Gizzard pH was higher in the control birds than in the test groups. Feed cost per kilogram of carcass weight was significantly (P < 0.05) lower with the dietary inclusion of CMOC. Conclusion. Replacing up to 30% of the maize with CMOC is beneficial and replacement up to 45% is not detrimental. However, the economic benefits of maize replacement with CMOC need to be re-evaluated with ingredient costings less affected by the present COVID-19 pandemic. Implications. Maximum utilisation of cassava root and moringa leaf meal in the diet will reduce cost and improve income of small-to medium-holder broiler producers.

Assessment of Heavy Metals Contamination and Antimicrobial Drugs Residue in Broiler Edible Tissues in Bangladesh.

There are substantial public health consequences when hazardous heavy metal contaminants and antimicrobial drug residues are present in broiler edible tissues. This study aimed to assess the concentration of antimicrobial drugs and heavy metals residues in broiler meat, bones and edible composites (combinations of liver, kidney and gizzard). Samples were collected from different types of broiler farms, broiler wet meat markets and supermarkets, covering all five divisions of Bangladesh. The antimicrobial drug and heavy metal residues were analyzed by uHPLC and ICP-MS, respectively. In addition, a cross-sectional survey was conducted among broiler meat consumers in the study areas to evaluate their attitude towards the consumption of broiler meat. The survey clearly stated that broiler meat consumers in Bangladesh have a negative attitude toward the consumption of broiler meat, although all respondents reported to eat broiler meat regularly. The antibiotic with the highest prevalence of residues in broiler edible tissues was oxytetracycline, followed by doxycycline, sulphadiazine and chloramphenicol. On the other hand, all collected broiler edible tissues contained chromium and lead, followed by arsenic. The fact of the matter is that the antimicrobial drugs and heavy metals residues were found to be below the maximum residue limit (MRL), except for the lead content. In addition, the broiler meat samples from supermarkets had lower levels of antimicrobial drugs and heavy metals residue compared to the broiler meat collected from various types of farms and broiler wet meat markets. Irrespective of the source, broiler meat was found to contain antimicrobial drugs and heavy metals residues below the MRL, except for lead, suggesting that broiler meat is safe for human consumption. Therefore, raising public awareness regarding misconceptions about broiler meat consumption among consumers would be warranted.

The influence of dietary Salvia and lavender powders on productive performance, some physiological parameters, and immunity of broiler under stocking density stress

The purpose of this experiment was to increase poultry meat production by increasing the number of chickens reared in the same area and managing it by using medicinal herbs Salvia officinalis L and Lavandula angustifolia L. in the broiler chicken diet. 705 one-day-old chicks were randomly distributed into to7 treatments with three replicates for an area of two m2 floor system in each replicate for each treatment, during 35 days of the study. T0 negative control 75 chicks, 25 chicks for each replicate 12-13 chicks per m2 fed standard diet. T1 positive control (stocking density without supplementation)105 chicks, 35 each replicate chicks 17-18 per m2 fed standard diet. The same stocking density for T2, T3, T4, T5, and T6 have been given standard feed with supplemented herbals, salvia 0.7%, 0.9%, lavender0.7%, 0.9%, and mixed 0.7% respectively. Depending on the results, chickens reared in stress stocking density with supplementations led to higher improvement of body weight, meat production, body weight gain (BWG), feed conversion ratio(FCR g feed/g weight), production index PI, carcass weight (g) and dressing percentage, RBCs 106cells/mm3, lymphocyte%, of increasing activity of thyroid hormones T3, T4 (nmol/L) boost antibody titers of ND and IBV when compared with positive control. However, heterophil%, stress indicator H/L ratio, glucose mg/ dL and cholesterol mg/ dL significantly reduced. The results showed that adding sage and lavender plants to broiler feed is effective in improving productivity, immunity, and resistance characteristics in reducing the adverse effects of stress caused by increasing the intensity of broiler rearing in the same area.

Assessment of Biosecurity Status of Broiler Farm at Jamalpur District

Broiler chicken production is an important source of animal protein supply, but the biosecurity conditions of Jamalpur region are not satisfactory. This study was done to gauge farmers' knowledge of and adherence to biosecurity guidelines of a broiler farm. We visited five randomly selected farms in two unions of Jamalpur district. The questionnaires were developed based on "biosecurity guideline for commercial poultry industry in Bangladesh”, provided by the department of livestock services of Bangladesh. There were 143 parameters, and each one of them bears 1 point. For each parameter that a farm followed, it gained one (1) point. The parameters were divided into 5 different principles: isolation, good farm hygiene, flock health care and monitoring, good farm management practices, and compliance with government regulations. Farm hygiene and compliance with government regulations were most commonly ignored principle by all the farms, especially in case of farm worker's hygiene All the farm had trees adjacent to the shed. The highest score was 62 (43.37%), gained by Farm 2, and the lowest point was 37 (25.87%) gained by Farm 1. The average score was 50 (34.97) points. This is the first survey work in this region, but there were difficulties in working with a larger number of farms due to the COVID-19 pandemic with frequent lockdowns. This study may help to improve the biosecurity conditions of broiler chicken production in small stockholders of this region. © 2022 The Author(s).

Analysis of Antimicrobials in Muscle and Drinking Water in Terms of Reducing the Need of Antimicrobial Use by Increasing the Health and Welfare of Pig and Broiler.

Antimicrobial residues may pose harmful effects on the health of consumers. At the same time, an adequate quality of drinking water for animals is one of the important element to ensure animal welfare and food without antibacterials. The presented study is aimed at estimating the residue levels of antibacterial compounds, such as penicillins, cephalosporin, macrolides, tetracyclines, quinolones, sulphonamides, aminoglycosides, diaminopirymidines, pleuromutilines and lincosamides in meat and on-farm drinking water samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS), as a part of a surveillance system on pig and broiler farms within the project Healthy Livestock. A total of 870 samples of muscle from pig and broiler, as well as 229 water samples were analysed for antibiotic residues. Samples were collected from farms in EU countries in two steps, before and after implementation of a tailor-made health plan. In muscle samples, the detected concentrations of doxycycline in the post-intervention step (15.9-70.8 µg/kg) were lower than concentrations in the pre-intervention step (20.6-100 µg/kg). In water samples, doxycycline in an average concentration of 119 µg/L in the pre- and 23.1 µg/L in the post-intervention step, as well as enrofloxacin at concentrations of 170 µg/L in the pre- and 1.72 µg/L in the post-intervention step were quantified. Amoxicillin was only present before intervention. The obtained results confirm the effectiveness of the intervention actions. The concentrations of antibiotics in muscles and water were lower after implementation of a health plan on the farms.

Ameliorative effects of 25-hydroxycholecalciferol levels on broiler chickens challenged with infectious bronchitis coronavirus: A novel approach

This study aimed to see how 25-hydroxyvitamin D3 [25(OH)D] supplementation affected the performance, immunity, and vitamin D status of broilers, with and without infectious bronchitis virus challenge. Day-old chicks (n = 1000) were divided into four dietary treatments. All experimental treatments were containing 5000 IU of D3 and supplemented with 0, 100, 300, or 500 g/tonne of Bio D containing 0, 13.94, 41.82, or 69.70 mg 25(OH)D, respectively. In unchallenged birds, the inclusion of 25(OH)D significantly improved survival rates and EPEF values, and no significant difference in LBW, BWG, FC, or FCR was observed. In infectious bronchitis virus (IBV)-challenged birds, the 25(OH)D treatment showed less deterioration in BWG, and FC compared with the control, especially 25(OH)D500 group. The lowest mortality was observed in the 25(OH)D500 group. The health status of chicks fed diets supplemented with 25(OH)D post-challenge had significantly better CD4, CD8, and immunoglobulin (IgG, IgM) levels, H/L ratio, total leucocytic count (TLC) in peripheral blood and IBV titers, cytokine (including interleukin (IL) 10) and (IFN)-γ expression, and reduced IBV shedding. After IBV challenge, all 25(OH)D groups recorded higher levels of plasma vitamin D than the control. Furthermore, 25(OH)D groups showed significantly higher antibody titers than the control group. In general, dietary supplementation with different levels of 25(OH)D had a positive effect on inflammatory reaction and stimulated the systemic innate immune responses of chickens during IBV challenge. In turn, recovery in the challenged birds with 25(OH)D rapidly occurred compared with that in the control group. © 2022 The Authors

Geographic distribution of IBV lineages

Infectious bronchitis virus (IBV) is a leading cause of economic losses within the poultry industry, affecting both meat-type birds and layers. The highly contagious viral disease caused by Avian coronavirus was first described in the 1930s and still remains a global problem for the poultry industry. Infection by Avian coronavirus causes respiratory disease, nephritis, decreased egg production depending on the viral pathotype and the age of the affected flocks. Live attenuated and inactivated vaccines are used to control the disease, but poor cross-protection between different serotypes complicates control efforts. IBV exists in a wide variety of genetically distinct types and new variants are identified relatively frequently. As the emergence of new IBV variants may impede the efficacy of the vaccines, monitoring the prevalence and genetic characteristics of IBV is of utmost importance. Currently, a phylogeny-based classification system defined by Valastro and coworkers is used for the classification of IBV strains. At present, IBV strains are divided into 8 genotypes (GI-GVIII) and 39 distinct lineages (GI-1 to GI-31, GII-1, GII-2, GIII-1, GIV-1, GV-1, GVI-1, GVII-1 and GVIII-1) and a huge number of unclassified inter-lineage recombinants. Most IBV lineages are confined to specific geographic regions, and some countries report the circulation of unique lineages. In contrast, the GI-1, GI-13, GI-16 and GI-19 lineages are widely distributed. The aim of this review is to summarize the most recent knowledge about the distribution of the genetic groups of Avian coronavirus.

Evaluation of a Novel Precision Biotic on Enterohepatic Health Markers and Growth Performance of Broiler Chickens under Enteric Challenge.

This study evaluated the supplementation of a precision biotic (PB) on the enterohepatic health markers and growth performance of broiler chickens undergoing an enteric challenge. In the first study, three treatments were used: Unchallenged Control (UC); Challenged Control (CC; dietary challenge and 10× dose of coccidia vaccine); and a challenged group supplemented with PB (1.3 kg/ton). In the second study, three treatments were used: control diet, diet supplemented with Avilamycin (10 ppm), and a diet supplemented with PB (0.9 kg/ton). All the birds were exposed to natural challenge composed by dietary formulation and reused litter from a coccidiosis positive flock. In Trial 1, PB decreased ileal histological damage, increased villi length, and the expression of SLC5A8 in ileal tissue versus CC; it reduced ileal expression of IL-1ß compared to both UC and CC treatments. PB increased the expression of cell cycling gene markers CCNA2 and CDK2 in the ileum compared to CC. In Trial 2, PB improved the growth performance, intestinal lesion scores and intestinal morphology of broiler chickens. These results indicate that birds supplemented with PB are more resilient to enteric challenges, probably by its action in modulating microbiome metabolic pathways related to nitrogen metabolism and protein utilization.

Ameliorative Effects of 25-Hydroxycholecalciferol Levels on Broiler Chickens Challenged with Infectious Bronchitis Coronavirus: A Novel Approach

SUMMARY This study aimed to see how 25-hydroxyvitamin D3 [25(OH)D] supplementation affected the performance, immunity, and vitamin D status of broilers, with and without infectious bronchitis virus challenge. Day-old chicks (n = 1000) were divided into four dietary treatments. All experimental treatments were containing 5000 IU of D3 and supplemented with 0, 100, 300, or 500 g/tonne of Bio D® containing 0, 13.94, 41.82 or 69.70 mg 25(OH)D, respectively. In unchallenged birds, the inclusion of 25(OH)D significantly improved survival rates and EPEF values, and no significant difference in LBW, BWG, FC, or FCR was observed. In infectious bronchitis virus (IBV)-challenged birds, the 25(OH)D treatment showed less deterioration in BWG, and FC compared with the control, especially 25(OH)D500 group. The lowest mortality was observed in the 25(OH)D500 group. The health status of chicks fed diets supplemented with 25(OH)D post-challenge had significantly better CD4, CD8, and immunoglobulin (IgG, IgM) levels, H/L ratio, total leucocytic count (TLC) in peripheral blood and IBV titers, cytokine (including interleukin (IL) 10) and (IFN)-γ expression, and reduced IBV shedding. After IBV challenge, all 25(OH)D groups recorded higher levels of plasma vitamin D than the control. Furthermore, 25(OH)D groups showed significantly higher antibody titers than the control group. In general, dietary supplementation with different levels of 25(OH)D had a positive effect on inflammatory reaction and stimulated the systemic innate immune responses of chickens during IBV challenge. In turn, recovery in the challenged birds with 25(OH)D rapidly occurred compared with that in the control group.

INCOME ANALYSIS ON BROILER CHICKEN FARMING IN PARTNERSHIP SYSTEM DURING THE COVID-19 PANDEMIC IN TANRALILI DISTRICT, INDONESIA

This study was aimed to determine the income of farmers who carry out a partnership system during the COVID-19 Pandemic in Lekopancing Village, Tanralili District, Maros Regency. The research was conducted on March to April 2021. The type of research used is descriptive quantitative. The sample in this study were farmers who partnered with the X’s company were 2 farmers, the Y’s company were 12 farmers and the Z’s company were 8 breeder. Data was collected through interviews with the help of a questionnaire as the research instrument. The results showed that the COVID-19 pandemic impacted to the incomes of farmers who partnered with companies X, Y, and Z, other than that it influence price fluctuations. The income earned by farmers with partnership patterns on a business scale of 3000 tail is the highest breeder who partners with PT. Z was USD 1,564.63 and USD 0.52/tail/period. As for the business scale of 4000, the highest is PT. Y of USD 2,285.97 and USD 0.76/tail/period. © 2022. Online Journal of Animal and Feed Research. All Rights Reserved.

THE VOLATILITY OF BROILER MEAT PRICES IN TRADITIONAL AND MODERN MARKETS BEFORE, AT THE BEGINNING OF, AND DURING THE COVID-19 PANDEMIC IN JAMBI CITY

This study aimed to analyze the volatility of broiler meat prices before, in the beginning, and during the Covid-19 pandemic in traditional and modern markets in Jambi City and the forecast model. This study uses weekly time series data on broiler meat prices with the following periods: a) before the Covid-19 pandemic, the period March 2019 to February 2020;b) the beginning of the Covid-19 pandemic for the period March 2020 to August 2020;c) the Covid-19 pandemic period September 2020 to August 2021, sourced from the National Strategic Food Price Information Center. Data analysis was conducted using the coefficient of variation, ARIMA, ARCH, and GARCH. The price volatility of broiler meat in traditional markets is higher than in modern markets before, early, and during the Covid-19 pandemic. The highest price volatility occurred before the Covid-19 pandemic. The ARIMA model can predict the future price value of broiler meat in traditional and modern markets. The novelty of this research is the behavioral diversity and volatility of broiler meat prices before, in the beginning, and during the Covid-19 pandemic in traditional and modern markets in Jambi City. In addition, another novelty is the right forecast model to predict the future broiler meat prices in traditional and modern markets. © 2022 Science Press. All rights reserved.

The temporal pattern and relationship of Campylobacter prevalence in broiler slaughter batches and human campylobacteriosis cases in Sweden 2009-2019.

Thermophilic Campylobacter species are the most common cause of bacterial gastroenteritis worldwide, and handling and consumption of broiler meat is considered a major foodborne transmission route. Both the incidence of campylobacteriosis and the prevalence of Campylobacter in broilers show seasonality but the impact of this association and broiler prevalence on human incidence is not clear. To explore this relationship we applied two approaches for analyzing time series data using different time resolutions (weekly, bi-weekly or monthly data) of human campylobacteriosis cases and prevalence of Campylobacter spp. in broiler slaughter batches in Sweden between 2009 and 2019. The decomposition of time series into seasonal (S), long-term trend (T) and residual components (STL model) showed a close overlap in seasonal patterns in terms of timing and the proportional change of peaks from normalized yearly levels. Starting 2016, when a large outbreak was reported, there was significant overlap in the trend components as well. The trend component of human cases prior to the outbreak corresponded to a linear increase of 6.5 % cases annually. In comparison, the estimated annual increase in broiler consumption was 2.7 %. An additive approach for time-series counts incorporating seasonal and epidemic (cases are a function of previous cases) components found a positive association between human cases and broiler prevalence with an optimal lag of 2 weeks, 1 bi-week, or 0 months. Considering the estimated time between slaughter and consumption, incubation time, and the time between on-set of disease and testing, a 2-week lag may be consistent with transmission via handling and consumption of fresh broiler meat. The best model included broiler prevalence as a factor in the epidemic model component, not in the seasonal component. The outcomes in terms of best model, optimal lags and significance of parameters, using weekly, bi-weekly or monthly data were, in general, in agreement but varied with data resolution when only a subset of the time series, not including any known broiler associated outbreaks, was analyzed. The optimal resolution based on the available data and conditions of the present analysis appeared to be weekly or bi-weekly data. Results suggest that broiler prevalence with a 2 week lag period can explain part of the human cases but has a smaller explanatory impact during the part of the study period not including the large known outbreaks. There is no simple relationship between broiler prevalence and human cases. Additional factors than broiler prevalence need to be evaluated in order to understand the transmission routes and epidemiology of campylobacteriosis.

Growth performance, carcass and meat quality, bone strength, and immune response of broilers fed low-calcium diets supplemented with marine mineral complex and phytase.

Influence of marine mineral complex (CeltiCal) as a partial substitute for limestone on growth efficiency, carcass traits, meat quality, bone strength, calcium (Ca) retention, and immune response was investigated in broilers fed low-Ca diets with or without phytase (PHY) addition for a 35-d trial period. A total of 300 one-day-old Ross 308 straight-run broilers were randomly allocated to: T1 (positive control), recommended Ca levels + PHY; T2 (negative control), 0.2% below the recommended Ca levels + PHY; T3, 0.1% below the recommended Ca levels + 0.2% CeltiCal + PHY; T4, 0.2% below the recommended Ca levels + 0.4% CeltiCal + PHY; T5, 0.2% below the recommended Ca levels + 0.4% CeltiCal. PHY was added at 500 phytase units/kg diets. Each dietary treatment had 10 replications of 6 chicks each. Results revealed that production efficiency factor was greater for T4 compared to T2 and T5 during 22-35 d and for T1, T3, and T4 compared to T2 during 0 to 35 d (P < 0.05). Feed conversion ratio was lower for T3 and T4 compared to T2 and T5 during 0 to 35 d (P < 0.05). T4 had a greater (P < 0.05) dressing percentage than T2, which had a lighter (P < 0.01) small intestinal relative weight than all other treatments. Breast meat temperature at 15 min postmortem was highest for T1 and lowest for T3 (P < 0.001). Breast meat pH was greater for T1 compared to T5 at 15 min postmortem and for T3 compared to T4 at 24 h postmortem (P < 0.05). T5 had a lower breast meat redness than all other treatments at 15 min postmortem and then T1 and T3 at 24 h postmortem (P < 0.01). Tibia and femur weights were greater (P < 0.05) for T3, T4, and T5 compared to T2, which had the lowest tibia ash content (P < 0.05) and femur geometric properties (P < 0.001). Greater antibodies to infectious bronchitis virus (P < 0.01) and Ca retention (P < 0.001) were observed for T3 and T4 in comparison to T2. Based on the findings of this research, CeltiCal can adequately replace a considerable portion of limestone in broiler reduced-Ca diets containing PHY.

Respiratory health of broilers following chronic exposure to airborne endotoxin.

In and around poultry farms, high concentrations of endotoxins are found that have a negative impact on the health of farmers and local residents. However, little is known about the effects of chronic exposure to endotoxins on the health of poultry. The aim of this study was to identify effects of chronic exposure to airborne endotoxins (E. coli LPS) on the immune system, respiratory tract, disease susceptibility and welfare of broilers. Effects of high (HE) and low endotoxin (LE) concentrations on natural antibody titers (NAb), performance and behavior of broilers were determined. After treatment with a respiratory virus infection, infectious bronchitis virus (IBV), mRNA expression of cytokines and Toll-like receptor (TLR) 4 in the lung, tracheal ciliary activity and lesions in the respiratory tract were determined. Endotoxin affected the immune system and respiratory tract, where HE broilers tended to have lower IgM NAb binding Phosphorylcholine-conjugated to Bovine Serum Albumin, and higher interferon (IFN)-α mRNA expression and more lesions in the nasal tissue compared to LE broilers. Furthermore, HE broilers had higher TLR4 mRNA expression compared to LE broilers. However, endotoxin did not affect NAb levels binding Keyhole Limpet Hemocyanin, IFN-ß and interleukin-10 mRNA expression, IBV replication or lesions in the lung and trachea. HE and LE broilers further had similar body weight, but HE broilers showed numerically more passive behavior compared to LE broilers. In conclusion, chronic exposure to high airborne endotoxin concentrations affects components of the immune system and respiratory tract in broilers and could therefore influence disease susceptibility.

Evaluation of viral load and expression level of apoptotic genes in selected tissues of two hybrids of commercial broiler chickens challenged with infectious bronchitis virus: a comparative study.

Background: Infectious bronchitis virus (IBV) causes severe economic losses worldwide. IBV has a broad tissue distribution with different viral loads in different tissues. Additionally, IBV can induce apoptosis in infected cells. Aims: The present study aimed to evaluate the role of the genetic background of chickens in viral load and the expression level of apoptotic genes in different tissues of two hybrids of commercial broiler chickens (Ross 308 and Cobb 500) challenged with IBV. Methods: Chickens at 21 days of age were nasally challenged with 200 µL of allantoic fluid containing 104 EID50/ml of Iranian variant-2-like IBV (IS/1494). The expression level of apoptotic genes (Fas, FasL, Bax, and Bcl-2) in the tracheal and renal tissues and the amount of viral load in the tracheal, renal, and cloacal swab samples were investigated two, five, and seven days after IBV infection by RT-qPCR assay. Results: The amount of viral load and apoptotic the expression level of apoptotic genes in the tracheal (two and five days after infection) and renal samples (seven days after infection) were significantly higher in the Ross challenged group than in the Cobb challenged group.Furthermore, no difference was observed in the cloaca viral load on sampling days. Conclusion: To our knowledge, this is the first report that evaluated the role of the chickens' genetic background in the amount of viral load and the expression level of apoptotic genes against IBV. Further studies are needed to investigate the pathogenic characteristics of IBV in Ross 308 and Cobb 500 chickens.

Effect of Dietary L-Threonine and Toxin Binder on Performance, Blood Parameters, and Immune Response of Broilers Exposed to Aflatoxin B1.

To evaluate the effect of L-Threonine (L-Thr) and Mycofix® Plus (MP) on aflatoxicosis, an experiment with a 3-way ANOVA model was carried out with 8 replicates and 640 birds. Treatments included two levels of L-Thr (100% and 125% of the requirements, Cobb 500, Cobb-Vantress), Aflatoxin B1 (AFB1) (0, 500 ppb), and MP (0, 1 g/kg). As the main effects showed, AFB1 decreased breast meat yield and carcass percentage (p < 0.001), serum urea, antibody titer against infectious bronchitis virus (IBV), and bone density (p < 0.05), while it increased the plasma concentrations of glucose and alkaline phosphatase (ALP) (p < 0.05). Mycofix Plus improved the grower feed intake (FI), tibia fresh weight, and body weight (BW) to bone weight (p < 0.05). L-Threonine increased the grower FI, breast meat yield, serum aspartate transaminase (AST), and glutathione peroxidase (GPX) (p < 0.05). There were positive interactions with breast meat yield, cholesterol, lactate dehydrogenase (LDH), and IBV titer. Of the treatments used, the combination of L-Thr and MP without AFB1 improved breast meat and carcass percentage. L-Threonine and MP significantly improved IBV titer in birds challenged with AFB1 (p < 0.001). In conclusion, L-Thr and MP were beneficial to improve immunity.

Assessing the economic burden of multi-causal respiratory diseases in broiler farms in Iran.

The aim of this study was to find the direct economic losses due to the three viral causes of the avian respiratory syndrome, including Newcastle disease (ND), H9N2 influenza, and infectious bronchitis (IB) in stamped-out broiler farms during 2016-2017 across the country. This study was carried out on the information on cross-sectional monitoring in the years 2016-2017. The statistical society of the study was all the active broiler farms of the country stamped out due to respiratory syndrome. This study used compensation insurance data, and other sources. One-way ANOVA or Kruskal-Wallis tests were used to analyze normally and non-normally distributed data. In total, during the study period, 132 broiler farms and 1,723,131 fowls were stamped out. According to the results of the present investigation, the sum of costs and losses due to respiratory complex was 9.47 $US Million, 2016-2017 (5.72 from $US Million chicken meat losses and 3.75 $US Million was the total cost). ND was the main cause of economic losses and costs with 3.86 $US equal to 40.8% of the total. Cost of feeding was the highest followed by veterinary services and medicines, vaccination, and 1-day-old chicks costs with 2.27, 1.11, 0.33, and 0.036 $US Million, 2016-2017. In conclusion, we need to improve the preventive measures against respiratory viruses, especially NDV. Additionally, as the cost of feeding was the largest, it is important to shorten the time interval between disease occurrence and stamping out to reduce the cost.

Efficiency of Soybean Products in Broiler Chicken Nutrition.

The study aimed to determine the overall effect of replacing soybean meal completely with soybean expeller cake or extruded full-fat soybean in feed rations for broiler chickens on their carcass composition and meat quality. The experiment involved one hundred and twenty Ross 308 broiler chickens randomly allocated to three equinumerous groups (SBM, SEC, EFS). Each group was divided into five subgroups-each consisting of eight birds of both sexes (1:1). From Day 1 to Day 21 of life the birds were fed with loose starter rations, and from Day 22 to Day 42 they were fed grower rations based on a wheat meal, protein products and mineral and vitamin admixtures. The experimental factor was a protein raw material comprising: SBM group-soybean meal from GM (genetically modified) seeds, SEC-soybean expeller cake from n-GM seeds, and EFS-extruded full-fat soybean from n-GM seeds. The experimental diets were isocaloric and isonitrogenous. It was demonstrated that replacing soybean meal with SEC or EFS in feed rations for broiler chickens led to a significant (p < 0.05) weight gain on Day 42 of rearing by 4.57% and 2.88%, respectively. The chickens fed diets with EFS had worse (more than 4.14%) feed conversion rate (FCR) in comparison to the others (p < 0.05). Broiler chickens from the SBM and SEC groups showed a higher share of breast and leg muscles (by 4.74% and 7.54%) and a lower share of abdominal fat (by 31.1%) and skin with subcutaneous fat (by 18.8% and 13.4%) in comparison with birds from the EFS group (p < 0.05). The highest content of intramuscular fat with the best fatty acids profile was determined in the muscles of birds fed with diets containing EFS, while the muscles of chickens receiving SEC scored the highest. The results provide grounds for recommending SEC in broiler chicken nutrition as it allowed for obtaining the best production and slaughter results, whereas-from the point of view of the human diet-EFS should be recommended since it best modified the lipid fraction of muscles.

Determinants of SARS-CoV-2 Impacts on Small-Scale Commercial Broiler Production Systems in Egypt: Implications for Mitigation Strategies.

As in many other countries, the outbreak of the COVID-19 pandemic, together with subsequent government containment measures, posed significant challenges to small-scale broiler production systems in Egypt. Based on a survey of 205 specialist small-scale commercial broiler farms (SCBFs) consisting of both farm-based and household-based production systems, this study identifies the primary pathways through which COVID-19 has affected SCBFs and investigates the determinants of farm perception of these effects. A polychoric principal component analysis sorted the effects of the pandemic on the SCBFs surveyed into five categories, namely, input availability, production and operational costs, labor and human resources, consumer demand and sales, and farm finances. Next, five ordered logit models were constructed to examine the determinants of the SCBFs' perception of each category of these effects. Generally, the empirical results revealed that COVID-19 affected SCBFs heterogeneously based on their management and production systems and resource endowment. Female-led and household-based SCBFs perceived significantly greater COVID-19 effects. In contrast, individually owned farms and those with membership of poultry producer organizations and larger total asset values perceived fewer effects. In addition, SCBFs operating in both local and provincial markets were less likely to perceive negative effects from the pandemic on their broiler farming activities. Although the adoption of strict and immediate containment measures was essential for controlling the virus and protecting public health, our results indicate that policy responses to COVID-19 must consider the likely effects on small businesses such as SCBFs since disruptions to such socioeconomically important supply chains will intensify human suffering from the pandemic. Overall, our findings provide important implications for the formulation of effective strategies for mitigating the impact of COVID-19 on small-scale broiler production systems in Egypt and enhancing their preparedness and resilience to future pandemics, natural hazard risks, and market shocks.