Commercial Poultry Farms Research Articles

Characterization of S1 gene sequence variations of attenuated QX-like and variant infectious bronchitis virus strains and the pathogenicity of the viruses in specific-pathogen-free chickens.

Besides the vaccine strains, the Malaysian variant (MV) and QX-like are the predominant IBVs detected on commercial poultry farms. These two virus strains are distinct based on genomic and pathogenicity studies. In this study, we determined the sequence of the S1 gene and compared the pathogenicity of serial passage 70 (P70) of Malaysian QX-like (QX/P70) and MV (MV/P70) strains with that of their respective wild-type viruses. The nucleotide and amino acid sequences of the complete S1 genes of QX/P70 and MV/P70 showed 1.4 to 1.6% and 3.0 to 3.3% variation, respectively, when compared to the wild-type virus. Most of the mutations were insertions and substitutions in the hypervariable regions (HVRs), primarily in HVR 3. Furthermore, selection pressure analysis showed that both viruses are under purifying selection. A pathogenicity study in specific-pathogen-free (SPF) chickens showed a reduction in respiratory and kidney lesions in chickens inoculated with MV/P70, but not with QX/P70, when compared to the respective wild-type viruses. However, MV/P70 is still pathogenic and can cause ciliary damage. In conclusion, the MV IBV strain is more responsive than the QX-like IBV strain following the attenuation process used for the development of a live attenuated IBV vaccine.

Clinico-Pathological Investigation of Chicken Coccidiosis at Different Upazila in Bogura District

The experiment was conducted with the interest to know the overall condition of coccidiosis in small scale commercial poultry farms at different upazilla in Bogura district and the investigation was done from July to December, 2018. A thorough clinical and necropsy examination was done for characterizing the clinical signs, recording of gross lesions and collection of different organs mainly the small intestine and the caecum for further histopathological examination. A total of 343 suspected and dead chickens were examined, among them 52 (15.38%) (20.6% in broiler, 10.47% in sonali, 10.25% in layer) chickens were found positive for chicken coccidiosis. The proportional mortality rates were 19.25%, 21.42%, 8.23% and 7.5% respectively in age group of 0-4 weeks, 5-6 weeks, 7-8 weeks and above 8 weeks and the highest value was found in age group of 5- 6 weeks. Depression, ruffled feather, bloody diarrhoea, anaemia, drooping of wings and reduction of feed and water intake were commonly observed. Several gross changes were recorded including enlargement and discoloration of caecum, pinkish or blood mixed catarrhal contents in the intestinal lumen with numerous haemorrhagic lesions over intestinal mucosa. Histopathologically there was architectural destruction of caecum, destroyed and disorganized villi mucosa without any continuation of the lining epithelium. Some facts like farmers knowledge, the bio-safety measures and different protection programs with vaccination against the disease did not properly comply with the approved standards. Thus consideration of such points in management program of coccidiosis can improve the poultry farms of Bogura district.
 Res. Agric., Livest. Fish.7(2): 267-274, August 2020

Salmonella Bacteriophage Diversity According to Most Prevalent Salmonella Serovars in Layer and Broiler Poultry Farms from Eastern Spain.

Simple SummaryThere is a lack of knowledge about the impact that phages present in the environment may have against certain Salmonella serovars. Thus, an improved understanding of Salmonella phage diversity will provide a better insight into the role of phages in Salmonella ecology and diversity. The results of this study showed that the poultry farm environment could represent a valuable source of Salmonella phages, which are more varied in broiler than in layer farms.The exploration of novel nonantibiotic interventions in the field, such as the use of bacteriophages, is necessary to avoid the presence of Salmonella. Bacteriophages are a group of viruses widely distributed in nature, strictly associated with the prokaryotic cell. Researchers have demonstrated the success of phage therapy in reducing Salmonella counts in poultry products. However, the impact that phage concentration in the environment may have against certain Salmonella serovars is not well understood. Therefore, the aim of this study was to assess Salmonella phage prevalence in commercial poultry farms in terms of the production type: layers or broilers. The most prevalent Salmonella serovars isolated in poultry production were used for phage isolation. Salmonella specific phages were isolated from 141 layer and broiler farms located in the Valencia region during 2019. Analysis of the samples revealed that 100% presented Salmonella phages, the most prevalent being against serovar S. Enteritidis (93%), followed by S. Virchow (59%), S. Typhimurium (55%), S. Infantis (52%) and S. Ohio (51%). These results indicate that poultry farms could represent an important source of Salmonella phages. Nevertheless, further studies are needed to assess the epidemiology of phages against other serovars present in other countries and their diversity from the point of view of molecular studies.

An observational field study of the cloacal microbiota in adult laying hens with and without access to an outdoor range

BackgroundLaying hens with access to outdoor ranges are exposed to additional environmental factors and microorganisms, including potential pathogens. Differences in composition of the cloacal microbial community between indoor- and outdoor-housed layers may serve as an indicator for exposure to the outdoor environment, including its pathogens, and may yield insights into factors affecting the chickens’ microbiota community dynamics. However, little is known about the influence of outdoor housing on microbiota community composition in commercial layer flocks. We performed a cross-sectional field study to evaluate differences in the cloacal microbiota of indoor- vs outdoor-layers across farms.Eight layer flocks (four indoor, four outdoor) from five commercial poultry farms were sampled. Indoor and outdoor flocks with the same rearing flock of origin, age, and breed were selected. In each flock, cloacal swabs were taken from ten layers, and microbiota were analysed with 16S rRNA gene amplicon sequencing.ResultsHousing type (indoor vs outdoor), rearing farm, farm and poultry house within the farm all significantly contributed to bacterial community composition. Poultry house explained most of the variation (20.9%), while housing type only explained 0.2% of the variation in community composition. Bacterial diversity was higher in indoor-layers than in outdoor-layers, and indoor-layers also had more variation in their bacterial community composition. No phyla or genera were found to be differentially abundant between indoor and outdoor poultry houses. One amplicon sequence variant was exclusively present in outdoor-layers across all outdoor poultry houses, and was identified as Dietzia maris.ConclusionsThis study shows that exposure to an outdoor environment is responsible for a relatively small proportion of the community variation in the microbiota of layers. The poultry house, farm, and rearing flock play a much greater role in determining the cloacal microbiota composition of adult laying hens. Overall, measuring differences in cloacal microbiota of layers as an indicator for the level of exposure to potential pathogens and biosecurity seems of limited practical use. To gain more insight into environmental drivers of the gut microbiota, future research should aim at investigating community composition of commercial layer flocks over time.

Identification of High-Risk Areas for the Spread of Highly Pathogenic Avian Influenza in Central Luzon, Philippines.

Highly pathogenic avian influenza virus (HPAIV) is a major problem in the poultry industry. It is highly contagious and is associated with a high mortality rate. The Philippines experienced an outbreak of avian influenza (AI) in 2017. As there is always a risk of re-emergence, efforts to manage disease outbreaks should be optimal. Linked to this is the need for an effective surveillance procedure to capture disease outbreaks at their early stage. Risk-based surveillance is the most effective and economical approach to outbreak management. This study evaluated the potential of commercial poultry farms in Central Luzon to transmit HPAI by calculating their respective reproductive ratios (). The reproductive number for each farm is based on the spatial kernel and the infectious period. A risk map has been created based on the calculated R0. There were 882 (76.63%) farms with < 1. Farms with ≥ 1 were all located in Pampanga Province. These farms were concentrated in the towns of San Luis (n = 12) and Candaba (n = 257). This study demonstrates the utility of mapping farm-level estimates for informing HPAI risk management activities.

Infectious Laryngotracheitis in Layer Birds from Tamil Nadu, India

Infectious laryngotracheitis (ILT), caused by Gallid herpesvirus1, is one among the respiratory diseases of poultry gradually spreading worldwide, including Indian subcontinent. Present study was carried out to identify the pathogen from the suspected cases of the disease. The tracheal tissue samples (pooled) were collected from the birds suspected to have died of ILT from 26 commercial poultry farms located in and around Namakkal district of Tamil Nadu state of India. On post-mortem examination, haemorrhagic caseous exudate and fibrinous pseudo-membrane adhered to tracheal mucosa were noticed. A total of 22 farms were found positive through PCRs targeted against ICP4 gene and the thymidine kinase (TK) gene followed by confirmation through sequencing. Histopathology examination revealed decilliation, hyperplasia, degeneration and/or loss of tracheal epithelium with severe submucosal edema. There was infiltration with numerous lymphocytes, macrophages and plasma cells in milder infections, whereas presence of fibrinous exudates admixed with numerous erythrocytes and inflammatory cells like heterophils and lymphocytes were seen indicating the severe acute form of the disease. A fibrinous pseudomembrane was seen firmly attached to the inflamed and necrotic mucosa in subacute cases. Further, virus was isolated from randomly selected 5 PCR positive tracheal tissue samples in embryonated chicken eggs through chorioallantoic membrane (CAM) route. The typical pock lesions were observed on CAM along with engorged blood vessels and thickening of the membrane. Present study has reported the disease ILT among poultry flocks in the Namakkal district of Tamil Nadu and raises the concern for thorough investigation of the nature of prevailing pathogen in the region.

Movement Restriction and Increased Surveillance as Efficient Measures to Control the Spread of Highly Pathogenic Avian Influenza in Backyard Productive Systems in Central Chile.

During the last 5 years there has been an alarming number of reports of highly pathogenic avian influenza worldwide. However, little is known about the status of this disease in South America. Chile has been the only country in South America where an HPAI outbreak was reported. This outbreak occurred in 2002 and was due to an H7N3 HPAI, where the most plausible hypothesis that explained the entrance of the disease to the country, had relation to migratory wild birds. Commercial poultry farms in Chile are highly integrated and have high biosecurity standards. Nevertheless, poultry backyard production systems lack biosecurity measures and are widely distributed. Since 2002 outbreak, avian influenza viruses have been identified in wild birds and different animal species kept in backyard productive systems (BPS) in Chile. The aim of this study was to simulate the possible natural history of HPAI after its introduction to BPS in central Chile and to simulate different intervention strategies. To do so, the North American Animal Disease Spread Model version 3.3 was used. The results showed that a median of 15,930 BPS would be affected if HPAI spread among BPS in central Chile, representing 97.8% of the current amount of BPS existing in study zone. Movement restrictions, pre-emptive destruction, passive surveillance, tracing of infected premises and combinations of the three, where the intervention strategies tested in the simulation model. From all the interventions simulated, movement restrictions together with increasing surveillance (through increasing passive surveillance and good tracing of infected premises) had the biggest effect, reducing the median number of infected BPS in 90.8%. However, more studies are needed to more accurately estimate local contact rates. These results can guide the official veterinary services to consider potential mechanisms to control or prevent an HPAI emergency situation.

Estimating the introduction time of highly pathogenic avian influenza into poultry flocks

The estimation of farm-specific time windows for the introduction of highly-pathogenic avian influenza (HPAI) virus can be used to increase the efficiency of disease control measures such as contact tracing and may help to identify risk factors for virus introduction. The aims of this research are to (1) develop and test an accurate approach for estimating farm-specific virus introduction windows and (2) evaluate this approach by applying it to 11 outbreaks of HPAI (H5N8) on Dutch commercial poultry farms during the years 2014 and 2016. We used a stochastic simulation model with susceptible, infectious and recovered/removed disease stages to generate distributions for the period from virus introduction to detection. The model was parameterized using data from the literature, except for the within-flock transmission rate, which was estimated from disease-induced mortality data using two newly developed methods that describe HPAI outbreaks using either a deterministic model (A) or a stochastic approach (B). Model testing using simulated outbreaks showed that both method A and B performed well. Application to field data showed that method A could be successfully applied to 8 out of 11 HPAI H5N8 outbreaks and is the most generally applicable one, when data on disease-induced mortality is scarce.

Antimicrobials Used in Backyard and Commercial Poultry and Swine Farms in the Philippines: A Qualitative Pilot Study.

Chicken and pork are the most frequently consumed meat products in the Philippines. Swine and poultry are reared in either commercial farms (CMf) or backyard farms (BYf); the latter production system is relatively common and essential to food security in low- and middle-income countries (LMICs) such as the Philippines. Similar to resource-limited LMICs, antimicrobial use (AMU) surveillance has not yet been established; thus, AMU in food animals is a knowledge gap in understanding the emergence of antimicrobial resistance (AMR) in zoonotic foodborne bacteria in the country. This qualitative AMU pilot study aims to describe the antimicrobial active ingredients (AAIs) used and associated AMU practices (e.g., source of AAIs and informed AMU decisions) by poultry and swine CMf and BYf in the Philippines. Ninety-three farms across four regions in the Philippines voluntarily provided AMU information as part of a larger biosecurity and good practices study. The percentage of farms using AAI over the total number of farms was the metric used to describe AMU. In total, there were 30 AAIs used (CMf: n =27 and BYf: n = 13); per farm, the number of AAIs used ranged from 1 to 7. The spectrum of AAIs was more diverse in swine (n = 24) compared to poultry (n = 18). Enrofloxacin was the most frequently reported AAI in poultry (33%) and swine (36%) farms. Respiratory diseases were the most frequently reported reason for AMU in both species. Between production systems, significant differences were observed in the percentage of farms using amoxicillin (27% CMf vs. 3% BYf), colistin (17% CMf vs. 3% BYf), and oxytetracycline (12% CMf vs. 39% BYf). In terms of AMU practices, of important concern was the over-the-counter access of AAIs at retail outlets and the limited veterinary oversight in BYf. Our data indicated that antimicrobials critically important for human medicine are frequently used in poultry and swine farms in the Philippines. This study can inform the development of guidelines for curbing AMR through prudent AMU and serves as a reference point for AMU surveillance capacity development in the Philippines.

Preservative Effect of Newbouldia laevis (Boundary Tree) Leaf Extract on Shelf-Life of Fresh Chicken Meat under Tropical Conditions

The shelf life of chicken meat has been rapidly reduced as a result of high environmental temperatures prevalent in the tropics which favored the activities of spoilage micro-organisms, and reactive oxygen species that function in oxidative damage. Newbouldia laevis (N. laevis) possess valuable antioxidant and antibacterial properties. However, information on the effect of aqueous extracts of dry and wet leaves of N. laevis on preservation of fresh chicken meat under tropical condition is scanty and thus, investigated. Broiler chicken meat (10kg weight) was obtained immediately after slaughter and were randomly allotted to three treatments (T1- control; T2- aqueous extract of wet leaves of N. laevis; and T3- aqueous extract of dry leaves of N. laevis) in a Randomized Complete Block Design. Tropical plant, such as Newbouldia laevis with relatively high resistance to heat stress, possesses viable bioactive compounds that can lower the growth of spoilage micro-organisms and activities of reactive oxygen species on fresh chicken meat under tropical conditions for 48 hours. Hence, poultry farmers in developing nations with fluctuating power supply can adopt the quick meat shelf life enhancement technique, while commercial poultry farmers across the globe can embark on product fortification using extracts of Newbouldia laevis.

VETERINARY AND SANITARY EXAMINATION OF FOOD CHICKEN EGGS WITH THE BASIS OF COMMODITY QUALITY ASSESSMENT

The high nutritional and dietary properties of chicken eggs, the high economic efficiency of their production have led to the rapid growth and development of commercial poultry farming throughout the world. In this regard, the purpose of the research was the veterinary-sanitary examination of edible chicken eggs sold in retail, with the basics of product quality assessment. The objects of research were food eggs of the first category of different manufacturers: “Chebarkul bird”, “Poultry farm named after the 50th anniversary of the USSR”, “Nagaybaksky poultry-farming complex”. The following indicators were studied: the quality of packaging and labeling, commercial properties, consumer characteristics, morphological features, shelf life, nutritional value, safety indicators. It was established that the quality of products from such manufacturers as “Chebarkul bird” and “Poultry farm named after the 50th anniversary of the USSR” in the veterinary and sanitary relations and in the framework of the commodity examination met the requirements of the “Rules for veterinary and sanitary examination of poultry eggs”, State Standard 31654 - 2012, Sanitary Rules and Regulations 2.3.2.1078-01, Technical Regulations of the Customs Union 021/2011 and 022/2011. Products supplied to the trading network “Nagaybaksky poultry complex” possessed the best consumer characteristics and commodity properties, but the labeling of chicken eggs of this manufacturer needs to be improved in accordance with the requirements of the State Standard 31654-2012.

Avian mycoplasmosis monitoring in the Russian Federation in 2019

Under the conditions of intensive poultry farming and high concentration of poultry in a limited area mycoplasmoses cause significant economic damage to commercial poultry farming. Of greatest interest are respiratory mycoplasmosis and infectious synovitis, the causative agents of which are Mycoplasma gallisepticum and Mycoplasma synoviae, respectively. Considering that both diseases are included in the OIE list of notifiable diseases, it is necessary to perform constant control for their spread. The paper presents an analysis of serological test results for antibodies to mycoplasmosis agents in 2019. Six respiratory mycoplasmosis positive samples – and 129 infectious synovitis positive samples were detected when testing 2,401 chicken serum samples by the enzyme-linked immunosorbent assay (ELISA). The results of monitoring tests of samples received from 31 poultry farms (nine RF Subjects) indicate a decrease in the number of Mycoplasma gallisepticuminfected stocks and stable Mycoplasma synoviae situation. The respiratory mycoplasmosis epidemic situation on indoor poultry farms might have improved due to obtaining the poultry for commercial parent stocks from mycoplasmosis-free sources, better sanitary and hygienic conditions, elimination of the disease provoking factors, and the use of the disease-specific means of prevention in the parent broiler stocks. The infectious synovitis situation remains tense despite the fact that the number of Мycoplasma synoviae-infected farms decreased in comparison with the monitoring results for 2015–2018. Most seropositive stocks were detected on the layer farms (50.0% – in 2019). It seems appropriate to increase the amount of tests to be performed and the number of farms covered by testing in 2020 to more fully present the disease spread situation in commercial poultry farming in Russia.

Changes in the Percentages of B- and T-Lymphocytes and Antibody Titres in Laying Hens Infested with Dermanyssus gallinae-A Preliminary Study.

Simple SummaryDermanyssus gallinae, a hematophagous ectoparasite, adversely affects the health status of laying hens, leading to reduced egg production and significant economic losses in commercial poultry farms. The aim of this study was to determine the effect of D. gallinae on the immunological parameters (three lymphocyte subpopulations) and post-vaccination antibody titres (against most important avian pathogens) in layer hens during the egg production cycle. A total of 80 blood samples were collected at four time-points (B1–B4) from 10 Hy-Line Brown hens naturally infested with D. gallinae, which were randomly selected from a commercial layer farm. The infestation was monitored and treated twice with Biobeck PA 910 (active ingredient AI – silicon dioxide). The samples were collected before and after each treatment. The percentages of subpopulations of B cells and helper (Th) and cytotoxic (Tc) T cells were determined by flow cytometry. Antibody titres were determined by the immunoenzymatic method. The percentage of Th cells and post-vaccination anti-infectious bronchitis virus (anti-IBV) and anti-Newcastle disease virus (anti-NDV) antibodies decreased significantly at the second infestation peak when the number of parasites was twice higher than at the first infestation peak. There were non-significant correlations between the number of mites and antibody titres. These findings suggested that D. gallinae might inhibit humoral immune responses since the percentages of B cells and Th cells were negatively correlated with the number of mites. The percentage of Tc cells was positively correlated with the number of mites, which indicated that D. gallinae could stimulate cellular immune responses in infested laying hens. However, further research is needed to determine whether D. gallinae suppresses the production of vaccine-induced antibodies.(1) Background: Dermanyssus gallinae, a hematophagous ectoparasite, adversely affects the health status of laying hens, leading to reduced egg production and significant economic losses in commercial farms. The aim of this study was to determine the effect of D. gallinae on the development of post-vaccination immune responses in layer hens. (2) Methods: A total of 80 blood samples were collected at four time-points (B1–B4) from 10 Hy-Line Brown hens, randomly selected from a commercial layer farm. The flock was naturally infested with D. gallinae and treated twice with Biobeck PA 910 (AI silicon dioxide). The samples were collected before and after each treatment. The percentages of IgM+ B cells, CD3+/CD4+ T cells and CD3+/CD8a+ T cells were determined by flow cytometry; the titres of antibodies against avian encephalomyelitis, infectious bronchitis virus, Newcastle disease virus, Ornithobacterium rhinotracheale, reticuloendotheliosis virus and avian reovirus were determined by the immunoenzymatic method. (3) Results: The percentage of Th cells and post-vaccination anti-IBV and anti-NDV antibodies decreased significantly at the second infestation peak when the number of parasites was twice higher than at the first infestation peak. Non-significant negative correlations were found between the number of mites and the percentage of B cells (R = −0.845, p > 0.05) and between the number of mites and the percentage of Th cells (R = −0.522, p > 0.05), and a significant positive correlation was noted between the number of mites and the percentage of Tc cells (R = −0.982, p < 0.05). There were non-significant correlations between the number of mites and antibody titres. (4) Conclusion: The present findings suggested that D. gallinae might inhibit immune responses since the percentages of B cells and Th cells were negatively correlated with the number of mites. The percentage of Tc cells was positively correlated with the number of mites, which indicated that D. gallinae could stimulate cellular immune responses in infested laying hens. However, further research is needed to determine whether D. gallinae suppresses the production of vaccine-induced antibodies.

Detection and characterization of ESBL-producing Enterobacteriaceae from the gut of healthy chickens, Gallus gallus domesticus in rural Nepal: Dominance of CTX-M-15-non-ST131 Escherichia coli clones.

The surge in the prevalence of drug-resistant bacteria in poultry is a global concern as it may pose an extended threat to humans and animal health. The present study aimed to investigate the colonization proportion of extended-spectrum β-lactamase (ESBL) and carbapenemase-producing Enterobacteriaceae (EPE and CPE, respectively) in the gut of healthy poultry, Gallus gallus domesticus in Kaski district of Western Nepal. Total, 113 pooled rectal swab specimens from 66 private household farms and 47 commercial poultry farms were collected by systematic random sampling from the Kaski district in western Nepal. Out of 113 pooled samples, 19 (28.8%) samples from 66 backyard farms, and 15 (31.9%) from 47 commercial broiler farms were positive for EPE. Of the 38 EPE strains isolated from 34 ESBL positive rectal swabs, 31(81.6%) were identified as Escherichia coli, five as Klebsiella pneumoniae (13.2%), and one each isolate of Enterobacter species and Citrobacter species (2.6%). Based on genotyping, 35/38 examined EPE strains (92.1%) were phylogroup-1 positive, and all these 35 strains (100%) had the CTX-M-15 gene and strains from phylogroup-2, and 9 were of CTX-M-2 and CTX-M-14, respectively. Among 38 ESBL positive isolates, 9 (23.7%) were Ambler class C (Amp C) co-producers, predominant were of DHA, followed by CIT genes. Two (6.5%) E. coli strains of ST131 belonged to clade C, rest 29/31 (93.5%) were non-ST131 E. coli. None of the isolates produced carbapenemase. Twenty isolates (52.6%) were in-vitro biofilm producers. Univariate analysis showed that the odd of ESBL carriage among commercial broilers were 1.160 times (95% CI 0.515, 2.613) higher than organically fed backyard flocks. This is the first study in Nepal, demonstrating the EPE colonization proportion, genotypes, and prevalence of high-risk clone E. coli ST131 among gut flora of healthy poultry. Our data indicated that CTX-M-15 was the most prevalent ESBL enzyme, mainly associated with E. coli belonging to non-ST131clones and the absence of carbapenemases.

Practical Application of Miyazaki Jitokko Chickens Selected for a Superior Allele at a Single Nucleotide Polymorphism Site in the Cholecystokinin Type A Receptor Gene.

This study aimed to examine 1) whether selection for a superior allele at a single nucleotide polymorphism site (SNP; AB604331, g.420 C>A) of the chicken cholecystokinin type A receptor (CCKAR) gene in Miyazaki Jitokko chickens is detectable in commercial poultry farms, and 2) whether the reproductive traits of the Kyushu Rhode hens, as a maternal stock line of the Miyazaki Jitokko chickens, are affected by SNP selection. Conventional and A-allele fixed (improved) Miyazaki Jitokko chicks were hatched on the same day and raised in a battery cage until 7 days of age. The chicks were then deposited at two commercial poultry farms and reared until slaughter at 126 and 163 days for cockerels and pullets, respectively. Body weight on the day of hatching (day 0), at 5 days of age, and at slaughter were measured. The differences in the body weights of the farm and test groups at slaughter were analyzed using the generalized linear model. A-allele fixation increased the body weight at slaughter by approximately +123.5 g and +131.9 g in cockerels and pullets, respectively. No significant differences between the conventional and improved hens were detected in terms of egg-laying rate, fertilization rate, and hatchability in the Kyushu Rhode hens. The data suggest that fattening chicks can be supplied as usual, even if Kyushu Rhode hens are switched from the conventional to improved type. In conclusion, genetic improvements using the CCKAR SNP site as a marker were effectively established in terms of the growth of the Miyazaki Jitokko chickens in commercial farms and the reproductive traits of the Kyushu Rhode hens.

Estimating the level of disease risk and biosecurity on commercial poultry farms in New Zealand

ABSTRACT Aims: To collect baseline data on the contact risk pathways and biosecurity practices of commercial poultry farms in New Zealand, investigate the relationship between the farm-level disease contact risks and biosecurity practices, and identify important poultry health concerns of producers. Methods: A cross-sectional survey of all registered New Zealand commercial poultry operations was conducted in 2016 collecting information on farm demographics, biosecurity practices, and contact risk pathways. Survey responses were used to generate an unweighted subjective disease risk score based on eight risk criteria and a subjective biosecurity score based on the frequency with which producers reported implementing seven biosecurity measures. Producer opinions towards poultry health issues were also determined. Results: Responses to the survey response were obtained from 120/414 (29.0%) producers, including 57/157 (36.3%) broiler, 33/169 (19.5%) layer, 24/55 (44%) breeder, and 6/32 (19%) other poultry production types. Median disease risk scores differed between production types (p < 0.001) and were lowest for breeder enterprises. The greatest risk for layer and broiler enterprises was from the potential movement of employees between sheds, and for breeder enterprises was the on- and off-farm movement of goods and services. Median biosecurity scores also differed between production types (p < 0.001), and were highest for breeder and broiler enterprises. Across all sectors there was no statistical correlation between biosecurity scores and disease risk scores. Producers showed a high level of concern over effectively managing biosecurity measures. Conclusions: The uptake of biosecurity measures in the commercial poultry farms surveyed was highly variable, with some having very low scores despite significant potential disease contact risks. This may be related to the low prevalence or absence of many important infectious poultry diseases in New Zealand leading farmers to believe there is a limited need to maintain good biosecurity as well as farmer uncertainty around the efficacy of different biosecurity measures. Further research is needed to understand barriers towards biosecurity adoption including evaluating the cost-effectiveness of biosecurity interventions.

Performance of Avian Influenza Surveillance System, Ogun State Nigeria, 2015-2019

Background: In 2019, two Highly pathogenic avian influenza (HPAI) A(H5N8) outbreaks in poultry establishments in Bulgaria, two of wild birds in Denmark and one low pathogenic avian influenza (LPAI) A(H5N3) in captive birds in the Netherlands were reported. Nigeria recorded the first outbreak of Highly Pathogenic Avian Influenza (HPAI) in February 2006 in a commercial poultry farm. Nigerian Pandemic Preparedness and Action Plan for Avian Influenza were then used to respond. Although influenza sentinel surveillance has been established in several African countries including Nigeria, data about the performance of established surveillance systems are limited on the continent. We described the avian influenza (AI) surveillance system in Ogun State, accessed veterinary health workers and farmers knowledge, evaluated all its attributes and made recommendations to improve the AI surveillance system. Methods: We adopted 2001 CDC Updated Guidelines for Evaluating Public Health Surveillance Systems. We reviewed and analyzed passive surveillance data from Ogun State Ministry of Agric, key informant interviews were conducted for relevant stakeholders at the state level and Local Government divisional veterinary clinics and farms to obtain additional information on the operations of the system.

English

Newcastle disease (ND) is a highly contagious viral disease constituting a continuous threat to the poultry industry worldwide. This study evaluated the genetic characteristics of Newcastle disease viruses (NDVs) obtained from backyard commercial poultry farms and live bird markets during active and passive surveillance in different regions of Plateau and Nasarawa States of Nigeria between 2009 and 2017. The partial fusion (F) gene coding sequence and cleavage site of five NDV isolates was determined. This was aligned and compared with sequences of representative NDV from the GenBank. Deduced amino acid sequence of the protein revealed that four isolates had virulent motifs (112RRQKRF117) while one had an avirulent motif (112GRQGRL117). One virulent strain was recovered from an apparently healthy duck. Phylogenetic analysis based on comparison with different classes of NDVs revealed that two isolates clustered with genotype XIVb NDVs, another two isolates clustered with genotype XVIIa while one isolate clustered with genotype II. The phylogenetic analysis revealed that the velogenic isolates clustered with published class II genotype XIVb and XVIIa closely related to isolates from Benin and Niger republic. This highlights the need for ND control programmes to place more stringent measures on cross-border trade of live bird and poultry products to prevent the introduction of new strains of NDV that would be more difficult to control. Key words: Chickens, duck, live bird market, Newcastle disease virus, genotypes, Nigeria. &nbsp

Newcastle disease and its different applicable control options in poultry in Ethiopia

Backyard poultry production has been a long-established husbandry practice in Ethiopia. It is estimated that Ethiopia’s backyard poultry population is about 53.31 million. The productivity of backyard poultry is constrained by disease outbreak especially Newcastle disease. Newcastle disease is an endemic, highly contiguous, viral disease that affects birds in both intensive and extensive production system. Vaccination against Newcastle disease has been established as one of the many interventions’ strategies, geared towards the control of Newcastle disease outbreaks in these flock. Currently, in Ethiopia, four types of Newcastle disease vaccines (HB1, Lasota, IOENDV, and Thermo-stable–12 vaccine) are used for the control of Newcastle disease. The application of conventional vaccination strategy for the control of Newcastle disease has been effectively utilized in intensive poultry production system. However, these conventional vaccination strategies against Newcastle disease outbreaks have not been fully optimized in backyard poultry production. Consequently, the application of thermo-stable vaccine in the form of feed baits seems to be the most appropriate method for effective control of Newcastle disease in village backyard poultry. Many kinds of feed stuff have been tested as a carrier of the vaccine virus; some have been proved unsuitable, while others are relatively suitable. The proper application of vaccine and vaccination programs together with other measures like sanitation, good nutrition, high level of management in most of the commercial poultry farms in Ethiopia and avoiding of concurrent infections, the occurrence of Newcastle disease outbreaks is rarely reported.

A Data-Driven Prediction Method for an Early Warning of Coccidiosis in Intensive Livestock Systems: A Preliminary Study.

Simple SummaryThe development of new methods, able to promptly detect the onset of the infection, is highly important to control parasitic infections of the intestinal tract (coccidiosis) in poultry. The early detection of this disease would reduce the use of anticoccidial and antimicrobials drugs, thus lowering the risk of antibiotic resistance. A data-driven machine learning algorithm was built to relate air quality data to the time of enteric disorders. The results show that this procedure has great potential to be used as a rapid technique to detect coccidiosis.Coccidiosis is still one of the major parasitic infections in poultry. It is caused by protozoa of the genus Eimeria, which cause concrete economic losses due to malabsorption, bad feed conversion rate, reduced weight gain, and increased mortality. The greatest damage is registered in commercial poultry farms because birds are reared together in large numbers and high densities. Unfortunately, these enteric pathologies are not preventable, and their diagnosis is only available when the disease is full-blown. For these reasons, the preventive use of anticoccidials—some of these with antimicrobial action—is a common practice in intensive farming, and this type of management leads to the release of drugs in the environment which contributes to the phenomenon of antibiotic resistance. Due to the high relevance of this issue, the early detection of any health problem is of great importance to improve animal welfare in intensive farming. Three prototypes, previously calibrated and adjusted, were developed and tested in three different experimental poultry farms in order to evaluate whether the system was able to identify the coccidia infection in intensive poultry farms early. For this purpose, a data-driven machine learning algorithm was built, and specific critical values of volatile organic compounds (VOCs) were found to be associated with abnormal levels of oocystis count at an early stage of the disease. This result supports the feasibility of building an automatic data-driven machine learning algorithm for an early warning of coccidiosis.