Commercial Chickens Research Articles

Dark brooder pullets are less active than Non-brooder pullets, but show similar level of synchronisation at the resource areas

Maternal care in commercial chickens can partially be replaced with dark brooders that offer heat and a dark area to rest and possibly avoid negative social interactions. Previous research has established the positive effects of dark brooders on reducing disturbance during resting in young pullets and injurious pecking in pullets and laying hens, which could reduce overall activity levels. The objective of this study was to employ precision livestock farming techniques to compare the overall activity levels and behavioural synchrony at resources in pullets reared with dark brooders until 41 days of age and those reared with whole house heating. Four brooder treatments, varying in size (Small/Large) and deployment method (Raised/Fixed), which could have implications for commercial use, were employed. Activity of the whole pen floor area and behavioural synchrony in drinker and feeder areas were automatically assessed over a 12-hour photoperiod at 10 and 60 days of age. Pixel change detection gauged overall activity across the pen, while an object detection model evaluated pullet behavioural synchrony. The analysis revealed increased activity levels in non-Brooder pullets compared to those in most Brooder treatments at both 10 and 60 days of age. However, no significant differences in behavioural synchrony were observed between Brooder and non-Brooder pullets. The underlying mechanism of dark brooder’s effects on the activity levels and behaviour synchrony remains unclear, but the observed reduction in activity levels in brooded pullets likely corresponds to increased resting behaviour and reduced injurious pecking. Furthermore, it is noteworthy that only a small percentage of pullets (up to 57.14%) were observed to use the resources simultaneously. This underscores the importance of conducting additional research to delve into the effects of resource allocation on both behavioural synchrony and activity levels in pullets. We observed minimal differences in the behaviour of pullets raised under different brooder types, suggesting that the simplest (Small-Fixed) brooders may be suitable for commercial use.

Phenotypic characterization and analysis of genetic diversity between commercial crossbred and indigenous chickens from three different agro-ecological zones using DArT-Seq technology.

Indigenous and were used to study genetic diversity and population structure analyses. Polymorphism information content (PIC) values ranged from 0.0 to 0.5, with 21,285 SNP markers (35%) being in the lowest PIC value range (0 to 0.15) while 13,511 (commercial chickens have developed unique adaptations to their environments, which may include nutrition, pathogens, and thermal stress. Besides, environmental pressures and artificial selection have generated significant genome-wide divergence in chickens, as those selection pressures contribute a considerable evolutionary force to phenotypic and genotypic differentiation. Herein, we determined genomic diversity of indigenous chickens from semi-deciduous rainforest (SDR), coastal savannah (CS) and Guinea savannah (GS) agro-ecological zones (AEZs) in Ghana and commercial crossbreds (CC) reared at the Kwame Nkrumah University of Science and Technology (KNUST). We generated SNP markers from 82 chickens (62 indigenous chicken ecotypes and 26 commercial crossbred ecotype) using DArT-Seq technology. A total of 85,396 SNP markers were generated and after filtering the data, 58,353 markers 21%) were in the highest PIC value range (0.45 to 0.50). The CC were more genetically diverse than the indigenous birds, with the highest expected heterozygosity value of 0.220. Between the commercial crossbreds population and the indigenous ecotypes, pairwise FST values were estimated to be 0.105 between CS, 0.096 between SDF, and 0.133 between GS. Furthermore, PCA analysis showed that the CC, SDF and GS chickens clustered together and are genetically distant from the commercial crossbred. We herein show that chickens from the AEZs studied can be considered as one population. However, due the abundance of agro-byproducts in the SDR compared to the CS and GS, chickens from the SDR AEZ had better growth compared to their counterparts. It is suggested that the genetic diversity within the local ecotypes could form the basis for genetic improvement.

Annotations of four high-quality indigenous chicken genomes identify more than one thousand missing genes in subtelomeric regions and micro-chromosomes with high G/C contents.

Although multiple chicken genomes have been assembled and annotated, the numbers of protein-coding genes in chicken genomes and their variation among breeds are still uncertain due to the low quality of these genome assemblies and limited resources used in their gene annotations. To fill these gaps, we recently assembled genomes of four indigenous chicken breeds with distinct traits at chromosome-level. In this study, we annotated genes in each of these assembled genomes using a combination of RNA-seq- and homology-based approaches. We identified varying numbers (17,497-17,718) of protein-coding genes in the four indigenous chicken genomes, while recovering 51 of the 274 "missing" genes in birds in general, and 36 of the 174 "missing" genes in chickens in particular. Intriguingly, based on deeply sequenced RNA-seq data collected in multiple tissues in the four breeds, we found 571 ~ 627 protein-coding genes in each genome, which were missing in the annotations of the reference chicken genomes (GRCg6a and GRCg7b/w). After removing redundancy, we ended up with a total of 1,420 newly annotated genes (NAGs). The NAGs tend to be found in subtelomeric regions of macro-chromosomes (chr1 to chr5, plus chrZ) and middle chromosomes (chr6 to chr13, plus chrW), as well as in micro-chromosomes (chr14 to chr39) and unplaced contigs, where G/C contents are high. Moreover, the NAGs have elevated quadruplexes G frequencies, while both G/C contents and quadruplexes G frequencies in their surrounding regions are also high. The NAGs showed tissue-specific expression, and we were able to verify 39 (92.9%) of 42 randomly selected ones in various tissues of the four chicken breeds using RT-qPCR experiments. Most of the NAGs were also encoded in the reference chicken genomes, thus, these genomes might harbor more genes than previously thought. The NAGs are widely distributed in wild, indigenous and commercial chickens, and they might play critical roles in chicken physiology. Counting these new genes, chicken genomes harbor more genes than originally thought.

Isolation and molecular characterization of very virulent infectious bursal disease virus from Egypt

In Egypt, the poultry industry is plagued by the significant economic losses caused by the infectious bursal disease virus (IBDV). In the present study, a total of 30 diseased commercial chicken flocks aged 23–41 days old in three Egyptian governorates (Fayoum, Beni-Suef, and Minya) having symptoms consistent with IBDV were examined. The collected bursal samples (n=30, ten pooled bursae for each flock) were screened by RT-PCR to amplify the IBDV VP2 gene. Results revealed that 20 out of 30 samples were positive, as indicated by the amplification of 620 bp of the VP2 gene. The twenty positive samples were inoculated into specific pathogen-free embryonated chicken eggs (SPF-ECEs) via the chorioallantoic-membrane (CAM) route to isolate the suspected virus. Eight samples were successfully isolated and were subjected to a partial sequence of VP2 (targeting the HVR). The nucleotide sequences and phylogenetic analysis revealed that the examined isolates exhibited amino acids A222, I256, I294, and S299, which are extremely conserved among very virulent (vv)IBDV. The amino acid sequence analysis of the eight isolates revealed a high degree of similarity (97-100%) in between and 90-100% similarity compared to other Egyptian vvIBDV strains. In contrast, lower similarity was observed with attenuated IBDV vaccine strains D78, Lukert, and Bursavac (91-93%, 91-93%, and 92-94%, respectively). In conclusion, this study underscores the importance of ongoing surveillance of the IBDV situation in the field, as well as the need for further research to investigate the efficacy of current vaccination strategies to curb IBDV infection.

Artificial selection footprints in indigenous and commercial chicken genomes

BackgroundAlthough many studies have been done to reveal artificial selection signatures in commercial and indigenous chickens, a limited number of genes have been linked to specific traits. To identify more trait-related artificial selection signatures and genes, we re-sequenced a total of 85 individuals of five indigenous chicken breeds with distinct traits from Yunnan Province, China.ResultsWe found 30 million non-redundant single nucleotide variants and small indels (< 50 bp) in the indigenous chickens, of which 10 million were not seen in 60 broilers, 56 layers and 35 red jungle fowls (RJFs) that we compared with. The variants in each breed are enriched in non-coding regions, while those in coding regions are largely tolerant, suggesting that most variants might affect cis-regulatory sequences. Based on 27 million bi-allelic single nucleotide polymorphisms identified in the chickens, we found numerous selective sweeps and affected genes in each indigenous chicken breed and substantially larger numbers of selective sweeps and affected genes in the broilers and layers than previously reported using a rigorous statistical model. Consistent with the locations of the variants, the vast majority (~ 98.3%) of the identified selective sweeps overlap known quantitative trait loci (QTLs). Meanwhile, 74.2% known QTLs overlap our identified selective sweeps. We confirmed most of previously identified trait-related genes and identified many novel ones, some of which might be related to body size and high egg production traits. Using RT-qPCR, we validated differential expression of eight genes (GHR, GHRHR, IGF2BP1, OVALX, ELF2, MGARP, NOCT, SLC25A15) that might be related to body size and high egg production traits in relevant tissues of relevant breeds.ConclusionWe identify 30 million single nucleotide variants and small indels in the five indigenous chicken breeds, 10 million of which are novel. We predict substantially more selective sweeps and affected genes than previously reported in both indigenous and commercial breeds. These variants and affected genes are good candidates for further experimental investigations of genotype-phenotype relationships and practical applications in chicken breeding programs.

The addition of calcium soap in the ration on the performance, carcass and abdominal fat of native chickens

This study aims to examine the effect of adding calcium soap (Ca-PFAD) to feed on performance, carcass and abdominal fat in native chickens. A total of two hundred and forty 6 week old native chickens were obtained from commercial native chicken farming with an average body weight of 662.52±21.75 g. All chickens were kept in a room with controlled environment. A total of 240 native chickens were divided randomly into four treatments, namely control feed without Ca-PFAD supplement as control (C0); feed supplemented with 2% Ca-PFAD (C1); added feed with 4% Ca-PFAD (C2); and diet supplemented with 6% Ca-PFAD. All diets were isocaloric and isonitrogen. Each treatment had six replications and each replication had 60 chickens. The results showed that the addition of 2-4% Ca-PFAD in feed significantly (P&lt;0.05) improved performance, carcasses, carcass percentage and carcass meat percentage. The amount of pad fat and abdominal fat in chickens decreased significantly (P&lt;0.05) with the addition of 2% Ca-PFAD in the feed. It can be concluded that the addition of 2% calcium soap (Ca-PFAD) in feed can improve performance and carcass quality in native chickens, on the other hand it can reduce the amount of abdominal fat.

Multi-Omics of Campylobacter jejuni Growth in Chicken Exudate Reveals Molecular Remodelling Associated with Altered Virulence and Survival Phenotypes.

Campylobacter jejuni is the leading cause of foodborne human gastroenteritis in the developed world. Infections are largely acquired from poultry produced for human consumption and poor food handling is thus a major risk factor. Chicken exudate (CE) is a liquid produced from defrosted commercial chicken products that facilitates C. jejuni growth. We examined the response of C. jejuni to growth in CE using a multi-omics approach. Changes in the C. jejuni proteome were assessed by label-based liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We quantified 1328 and 1304 proteins, respectively, in experiments comparing 5% CE in Mueller-Hinton (MH) medium and 100% CE with MH-only controls. These proteins represent 81.8% and 80.3% of the predicted C. jejuni NCTC11168 proteome. Growth in CE induced profound remodelling of the proteome. These changes were typically conserved between 5% and 100% CE, with a greater magnitude of change observed in 100% CE. We confirmed that CE induced C. jejuni biofilm formation, as well as increasing motility and resistance against oxidative stress, consistent with changes to proteins representing those functions. Assessment of the C. jejuni metabolome showed CE also led to increased intracellular abundances of serine, proline, and lactate that were correlated with the elevated abundances of their respective transporters. Analysis of carbon source uptake showed prolonged culture supernatant retention of proline and succinate in CE-supplemented medium. Metabolomics data provided preliminary evidence for the uptake of chicken-meat-associated dipeptides. C. jejuni exposed to CE showed increased resistance to several antibiotics, including polymyxin B, consistent with changes to tripartite efflux system proteins and those involved in the synthesis of lipid A. The C. jejuni CE proteome was also characterised by very large increases in proteins associated with iron acquisition, while a decrease in proteins containing iron-sulphur clusters was also observed. Our data suggest CE is both oxygen- and iron-limiting and provide evidence of factors required for phenotypic remodelling to enable C. jejuni survival on poultry products.

PERFORMANCE AND CARCASS EVALUATION OF BROILER CHICKENS FED DIFFERENT COMMERCIAL DIETS

An experiment was carried out to determine the utilization of five selected commercial broiler chicken diets by broilers. Three hundred day-old chicks were randomly allotted to five diets in replicates of three containing 20 birds each in a Completely Randomized Design. Feed and water were supplied ad libitum and the feeding trial lasted for six weeks. Results for overall performance, indicated that daily feed intake was higher (P&lt;0.05) on diets A (103.00 g), D (101.79 g) E (100.18 g) and B (96.06 g) which were the same and lower on diet C85.21 g) while daily weight gain and feed conversion ratio assumed the same trend as daily feed intake. Carcass evaluation showed a higher (P&lt;0.05) dressing percentage on diet D (76.72 %) and lowest on diet C (67.96 %). It was therefore concluded that diets D and A gave higher dressing percentages, hence recommended for broiler chicken farmers in the study area.

Plasmid-mediated quinolone resistance in Escherichia coli isolates from commercial broiler chickens in Semnan, Iran

Background and Objectives: Antibiotic resistance within the poultry sector presents a considerable health concern due to treatment inefficacy and resistance transmission to humans and the environment. The investigation of plasmid-mediated quinolone resistance (PMQR) in Escherichia coli, acknowledged for its role in advancing resistance, remains inadequately studied in Iranian poultry. This study aimed to evaluate PMQR gene prevalence as well as to determine correlation between resistance phenotype and genotype in E. coli obtained from poultry colibacillosis. Materials and Methods: A collection of 100 E. coli isolates from the viscera of broilers suspected to colibacillosis was assessed. Using the Kirby-Bauer disk diffusion method, antimicrobial susceptibility tests were conducted for ofloxacin, nalidixic acid, levofloxacin, ciprofloxacin, and ampicillin. Additionally, PCR was employed to screen for qnrS, qnrB, and aac(6)Ib-cr genes. Results: Among the analyzed E. coli isolates, 51% demonstrated resistance to at least one of the tested antibiotics, with 17% exhibiting resistance to four different antibiotics. Nalidixic acid displayed the highest resistance rate at 48%, while ampicillin had the lowest at 16%. PMQR genes were detected in 28% of the E. coli isolates, with aac(6′)-Ib-cr being the most prevalent at 14%, followed by qnrB in 13%, and qnrS in 7%. Conclusion: The study underscores the vital need for careful antibiotic usage in poultry to curb the emergence of antibi- otic-resistant bacteria. The results illuminate the prevalence of PMQR genes and their association with resistance trends in Iranian poultry, forming a pivotal basis for forthcoming approaches to combat antibiotic resistance within the poultry sector.

Performance Evaluation of Lohman Brown Commercial Layer Chicken Breeds Under On-Station Management at Pawe, Benishangul Gumuz, Ethiopia

This study was undertaken to evaluate the performance of Lohman Brown under on-station conditions at Pawe Agricultural Research Center. To evaluate the breed production performance and to generate information for private commercial farms and multiplication centers. A total of 100 (sixty-day-old) chicks and commercial layer feed were purchased from Alema poultry farm in Bishoftu. Vaccinations were administered to the chicks while bio-security measures were employed throughout the experimental period (83 weeks). Daily feed intake, body weight, feed conversion rate, egg production, egg weight, egg mass, and mortality, were recorded. Data were analyzed using descriptive statistics free R-4.0.4 software. Average feed intake during the growing period (10-20 weeks) 59.29g/head and in the layer period (21-72weeks) 117.26g/head/day. The average feed conversion rate at12, 16 and 20weeks of age was 8.85, 8.23 and 7.35 respectively. Average body weight at age at first egg lay and peak egg production were 1368.6 and 1553.9g/head respectively. Average daily weight gain at 10-12, 12-16, and 16- 20 weeks of age was 5.43, 7.22 and 11.09g/bird respectively. Age at first and 5% egg-laying were recorded at the beginning of 21weeks (141days). Age at 50% and peak egg production were recorded at 22 weeks (151 days) and 36weeks. The average HHEP (90.71) and HDEP (92.03) were recorded at peak production, while the overall percentage of lay from 21-72(52) weeks of age were HHEP (74.77%) and HDEP (78.28%). The total amount of egg production from 21-72(52) weeks of age in terms of HHEP and HDEP was 272.2 and 284.93egg/hen/year. Average egg weight at age at first egg lay, 50% egg lay and peak egg production were 47.43, 51.5 and 57.03g. Overall mean egg weight from 21-72(52) weeks of age was 57.81g. The average daily egg mass at the age of first egg lay, 50% egg lay and peak egg production were 7.59, 25.68, and 52.48g. On the other hand, the overall mean daily egg mass from 21-72(52) weeks of age was 45.38g. The average feed conversion rate and feed conversion efficiency for egg mass from 21-72 weeks were 2.64 and 0.387. There was no mortality record up to 28 weeks but, the overall mortality rate was 10% up to 83 weeks. The higher egg production and lower mortality record showed that the breed is adapted in the study area. Lohman Brown is recommended for users with basic input packages and on-farm evaluation of chickens should be done.

Genetic Sequence and Pathogenicity of Infectious Bursal Disease Virus in Chickens in Egypt During 2017-2021.

The continued circulation of infectious bursal disease virus (IBDV) in Egypt, despite the use of various vaccines, is a serious problem that requires continuous detection of IBDV. In the current study, real-time reverse transcriptase polymerase chain reaction testing of 100 diseased chicken flocks during 2017-2021 revealed the presence of very virulent IBDV (vvIBDV) in 67% of the flocks, non-vvIBDV in 11%, and a mixture of both vvIBDV and non-vvIBDV in 4%. Twenty-nine IBDV isolates were submitted for partial sequencing of the viral protein 2 hypervariable region (VP2-HVR), and 27 isolates were confirmed to be genogroup A3 (vvIBDV) with 96.3%-98.5% similarity to the global A3 (vvIBDV) and 88.9%-97% similarity to genogroup A1 vaccine strains. The remaining two isolates were non-vvIBDV and showed 91.1% and 100% identity with classical genogroup A1 strains, respectively. Furthermore, the sequence and phylogenetic analysis of VP1 (amino acids 33-254) of two selected isolates of A3, 5/2017 and 98/2021, clustered them as B2, vvIBDV-like, strains with high similarity (99.5%) to four Egyptian, 99% to Chinese and European, and 97.7% to Chinese and Polish vvIBDV isolates. Experimental infection of commercial broiler chickens with two vvIBDV-A3B2 isolates (5/2017 and 98/2021) showed no mortality despite typical tissue lesions, clear histopathological changes, and strong ELISA antibody response. Isolate 98/2021 was more pathogenic, as confirmed by histopathology, whereas isolate 5/2017 induced a stronger serological response. In conclusion, vvIBDV (A3B2) strains with two amino acid (aa) substitutions in VP1 as V141I and V234I as well as VP2 as Y220F and G254S are still circulating in Egypt.

Elevated mortality in 3-week-old commercial broiler chickens.

Elevated mortality in 3-week-old commercial broiler chickens.

Poultry consumption and perceptions in Tehsil Shakargarh, Punjab, Pakistan: Implications for public health during COVID-19

This study investigated the habits and attitudes of individuals towards poultry consumption, utilizing primary data collected through a survey of 5 households from 285 localities in Tehsil Shakargarh, Punjab, Pakistan (n = 1425). Household selection was randomized, and personal visits were conducted for data collection via formal interviews employing a structured questionnaire. Coordinates for each site were obtained using a Garmin eTrex device, in conjunction with meteorological data, to determine global positioning system (GPS) coordinates. A notable portion of respondents (38.8 %) possessed basic knowledge, while the majority (61.2 %) demonstrated intermediate knowledge regarding commercial broilers (chickens raised for meat production). A significant proportion (70.3 %) harbored misconceptions about the inclusion of hormones/antibiotics in poultry feed, with a minority (0.2 %) misinformed about broiler chickens' leg weakness. Some respondents (17.3 %) held both misconceptions, while others (12.2 %) had none. The majority (97.6 %) favored egg consumption, with 51.7 % preferring commercial chicken eggs and 48.3 % opting for domestic chicken eggs. Preference for white-colored eggs (51.5 %) slightly outweighed that for brown-colored eggs (48.5 %). A minority (1.3 %) speculated that poultry consumption could be a potential cause of COVID-19, while the majority (65.7 %) disagreed, and a portion (33.0 %) remained uncertain. Nearly all respondents (99.9 %) believed in the immunity-boosting properties of protein intake, with 65 % associating such benefits with poultry meat and eggs. Similarly, 99.7 % did not encounter difficulties in accessing poultry products during lockdowns. Approximately half (46.3 %) of respondents believed that consuming well-cooked and safely handled poultry meat was safe during outbreaks. Poultry meat and eggs emerged as potentially efficient sources of nutrition during the COVID-19 pandemic, especially for protein-deficient populations like Pakistan. Therefore, initiatives should focus on enhancing commercial poultry production and educating the populace about its advantages.

Isolation and Identification of The Highly Pathogenic Avian Influenza H5N8 Virus Isolated From Commercial Layer Chickens in Al-Sharkia Province in Egypt During 2019-2021

Isolation and Identification of The Highly Pathogenic Avian Influenza H5N8 Virus Isolated From Commercial Layer Chickens in Al-Sharkia Province in Egypt During 2019-2021

Effect of Dietary Supplementation of Andrographis paniculata and Curcuma longa Powder on Growth Performance, Immunity and Carcass Characteristics of Commercial broiler Chicken

Effect of Dietary Supplementation of Andrographis paniculata and Curcuma longa Powder on Growth Performance, Immunity and Carcass Characteristics of Commercial broiler Chicken

Protection Against Infectious Bronchitis Virus Vaccine Recombinants and Chicken-Selected Vaccine Subpopulations.

Outbreaks of infectious bronchitis (IB) continue to occur from novel variants of IB virus (IBV) emerging from selection of vaccine subpopulations and/or naturally occurring recombination events. S1 sequencing of Arkansas (Ark) -type viruses obtained from clinical cases in Alabama broilers and backyard chickens shows both Ark Delmarva Poultry Industry (ArkDPI) vaccine subpopulations as well as Ark vaccine viruses showing recombination with other IB vaccine viruses. IB Ark-type isolates AL5, most similar to an ArkDPI vaccine subpopulation selected in chickens, AL4, showing a cluster of three nonsynonymous changes from ArkDPI subpopulations selected in chickens, and AL9, showing recombination with Massachusetts (Mass) -type IBV, were examined for pathogenicity and ability to break through immunity elicited by vaccination with a commercial ArkDPI vaccine. Analysis of predicted S1 protein structures indicated the changes were in regions previously shown to comprise neutralizing epitopes. Thus, they were expected to contribute to immune escape and possibly virulence. Based on clinical signs, viral load, and histopathology, all three isolates caused disease in naïve chickens, although AL9 and AL5 viral loads in trachea were statistically significantly higher (30- and 40-fold) than AL4. S1 gene sequencing confirmed the stability of the relevant changes in the inoculated viruses in the chickens, although virus in some individual chickens exhibited additional S1 changes. A single amino acid deletion in the S1 NTD was identified in some individual chickens. The location of this deletion in the predicted structure of S1 suggested the possibility that it was a compensatory change for the reduced ability of AL4 to replicate in the trachea of naïve chickens. Chickens vaccinated with a commercial ArkDPI vaccine at day of hatch and challenged at 21 days of age showed that vaccination provided incomplete protection against challenge with these viruses. Moreover, based on viral RNA copy numbers in trachea, differences were detected in the ability of the vaccine to protect against these IBV isolates, with the vaccine protecting the most poorly against AL4. These results provide additional evidence supporting that IBV attenuated vaccines, especially ArkDPI vaccines, contribute to perpetuating the problem of IB in commercial chickens.

Probiotic Potential of Autochthonous Lactobacillus against Avian Pathogenic Escherichia coli

Background: The aim of current study was to investigate the probiotic potential of autochthonous Lactobacillus species against pathogenic Escherichia coli in poultry. Method: A total of 73 samples were collected from cloacal swabs and tissues of desi and commercial chicken. The Lactobacillus were isolated based on cultural, biochemical and molecular teats. The probiotic potency was tested in vitro and antimicrobial activity and ABST was carried by Agar well diffusion and disc diffusion methods, respectively. Nucleotide sequencing was done by Sanger sequencing. Haemolysis and gelatin hydrolysis assays were used as safety testes. Result: From 73 cloacal swabs and tissues of desi and commercial chicken, 56 Lactobacillus were isolated of which 22 showed high autoaggregation and hydrophobicity potential. Based on survivability at acidic pH (2.5) and bile concentrations (0.5%), 16 isolates were selected and were subjected to well diffusion assay against pathogenic E. coli. All the isolates showed zone of inhibition against E. coli ranging from 10 -18 mm. ABST revealed that all the isolates are sensitive to chloramphenicol, ampicillin and erythromycin and 75% of the isolates were resistant to streptomycin, gentamicin and vancomycin. Only one isolate out of 16 tested was non hemolytic and none of the isolates tested positive for gelatine hydrolysis. Sequencing result of selected isolate revealed 96.82% of its similarity to Lactobacillus fermentum.

High quality assemblies of four indigenous chicken genomes and related functional data resources

Many lines of evidence indicate that red jungle fowl (RJF) is the primary ancestor of domestic chickens. Although multiple versions of RJF (galgal2-galgal5 and GRCg6a) and commercial chickens (GRCg7b/w and Huxu) genomes have been assembled since 2004, no high-quality indigenous chicken genomes have been assembled, hampering the understanding of chicken domestication and evolution. To fill the gap, we sequenced the genomes of four indigenous chickens with distinct morphological traits in southwest China, using a combination of short, long and Hi-C reads. We assembled each genome (~1.0 Gb) into 42 chromosomes with chromosome N50 90.5–90.9 Mb, amongst the highest quality of chicken genome assemblies. To provide resources for gene annotation and functional analysis, we also sequenced transcriptomes of 10 tissues for each of the four chickens. Moreover, we corrected many mis-assemblies and assembled missing micro-chromosomes 29 and 34–39 for GRCg6a. Our assemblies, sequencing data and the correction of GRCg6a can be valuable resources for studying chicken domestication and evolution.

Detection, Identification, and Characterization of Eimeria spp. from Commercial Chicken Farms in Different Parts of Iran by Morphometrical and Molecular Techniques.

Coccidiosis of domestic chicken is an important disease caused by any of seven species of Eimeria which, by developing within the epithelial cells of the intestine, cause lesions therein. We carried out a study on poultry farms located in various regions of Iran to determine the incidence and spread of Eimeria species by employing a single PCR test. A total of 64 fully confirmed clinically intestinal tracts were collected from different parts of Iran. From these 64 intestinal tracts, 82 samples were prepared from the different sites involved in the digestive tract. In morphological assessment, 23 samples could not be isolated and its information was not evaluated. Using morphological methods, the following seven species of Eimeria were identified: E. acervulina (15/59; 25.42%), E. tenella (30/59; 50.84%), E. maxima (12/59; 20.33%), E. praecox (1/59; 1.69%), E. necatrix (2/59; 3.38%), E. mitis (5/59; 8.47%), and E. mivati (2/59; 3.38%). Mixed infections were found in eight (13.55%) samples. In molecular assessment, 31 samples could not be isolated and its information was not evaluated. Totally, the following five species were identified using molecular methods: E. acervulina (35/51; 68.62%), E. tenella (33/51; 64.70%), E. maxima (6/51; 11.76%), E. brunetti (5/51; 9.80%), and E. necatrix (2/51; 3.92%). Mixed infections were found in 23 (45.09%) samples. The present study is an update on the situation of poultry coccidiosis in Iran and provides the first data on the molecular detection, identification, and characterization of Eimeria spp. in the poultry population of this country and confirmed the presence of different species of this parasite in this area. According to the results, E. acervulina and E. tenella, as the main disease-causing species, should be considered in control programs such as treatment and vaccination strategies.

Chicken dumping in South Africa and the long-term effects on local commercial chicken farming industry: a review

The aim of this article is to highlight the effects of chicken dumping trade on South African local commercial chicken farming industry. The high cost of farming in South African has risen and this has created a fertile ground for overseas countries where chicken production costs are low to intensify their exports to South Africa for their excess chicken products at a lower price. South African chicken farmers are already facing domestic challenges which includes high-cost feed, high cost of importing chicken lines and resources to produce the meat chicken. A local single fertilised Ross 308 / Cobb 500 Fertile egg cost at least R2.50 ($0.12), whereas international, local breeders source these genetic lines at over a $1 an egg. Locally, there is persistent drought, chicken diseases, high electricity cost and electricity shortages (load shedding). These challenges inevitably raise costs of chicken production in South Africa whereas the US, Brazil and EU countries farming industries are highly subsidised and experience no high electricity costs or load shedding. In perspective, imported chicken from Brazil cost R9 per kg as compared to locally produced chicken at R25 per kg. To mitigate the chicken dumping trade, the South African government imposed legally sound chicken import tariffs of up to 62 %, however in August of 2022, the government suspended these tariffs due to rising food costs in the hope that the cheap dumped chicken would provide a relief to the financially stressed consumers. This move has raffled feathers within the local chicken farming sector which is struggling to sustain their farms due to stiff competition with the low-priced chicken, predominantly from Brazil and the US. More chicken farms in South Africa are shedding jobs. As of 2023, the poultry industry in South Africa employs an estimated total of 70,000 people, and others are questioning the sustainability of their enterprises going forward if the chicken dumping in the country is not controlled via stringent legislation that include appropriate dumping tariffs. This article suggests that both the chicken farming industry, the chicken importers and the government should hold regular dialogs to get common ground before the majority of local chicken farmers close shops due to chicken dumping. The regular engagements between the government and the chicken industry could avoid seemingly unilateral suspension of import tariffs. Subsidies that could absorb some of the operation cost, as is the case with US or Brazilian farmers should be introduced. Key words: Chicken dumping, chicken farming, sustainability, chicken production challenges