Journal of World's Poultry Research

133-144

Authors: El-Nabarawy AM

The need for regulations to limit the concentration of mycotoxins in feed and food requires the availability of data on levels of contamination in different feedstuffs and estimation of the mycotoxin residues in animal meat. Therefore, this study was conducted to determine contamination levels with different mycotoxins in broiler feed and aflatoxin residues in broilers’ muscle and liver. A total of 194 feed samples, including 148 compound feeds and 46 feed ingredients, were collected from feed manufacturing companies and broiler farms. Feed samples were analyzed for detecting aflatoxins, ochratoxins, zearalenone, and fumonisins using an official analytical method. Moreover, aflatoxin residues were estimated in 64 broiler’s muscle and liver tissues. Obtained results revealed that 100% of compound broiler feed sampled from manufacturing companies were contaminated with aflatoxin and ochratoxin. Also, 96.4% and 92.8% of compound broiler feed sampled from broiler farms were contaminated with aflatoxin and ochratoxin, respectively. Furthermore, 30.6% and 91% of the feed samples were above the permissible levels of aflatoxin and ochratoxin. Aflatoxin residues were detected in all meat and liver samples with levels above the permissible limits. Large scale surveys for determination of different mycotoxins in poultry feed and mycotoxins residues in poultry products are of national and international importance.

151-164

Authors: Radi AM

Pasteurella multocida is one of the commensal flora of the upper respiratory tract. Under stress conditions, it may be involved as a secondary agent in various respiratory syndromes and caused high mortality as well as significant economic losses in chickens. This study evaluated the effect of bromhexine or thyme oil on enhancement of efficacy of tilmicosin in treatment of avian pasteurellosis. A total of 63 adult chickens were infected by Pasteurella multocida and classified into seven groups and treated as follow; non-infected non-treated group (control negative), infected non-treated group (control positive), group infected and treated by tilmicosin alone, group infected and treated by bromhexine alone, group infected and treated by thyme oil alone, group infected and treated by tilmicosin+bromhexine, and group infected and treated by tilmicosin+thyme oil. Clinical signs, mortality rate, bacterial re-isolation, hematobiochemical and histopathological parameters were determined. The results showed a significant decrease in mortality, bacterial re-isolation as well as clinical signs in combined treated groups compared to tilmicosin group as well as improvement in hematobiochemical and histopathological parameters of combined treated groups. Furthermore, the combination of tilmicosin and bromhexine or thyme oil was more potent in the treatment of pasteurellosis in chickens than each treatment alone. Finally, the clinically observed damage in chickens infected with P. multocida can be ameliorated by a combination of tilmicosin with bromhexine or thyme oil. This protective effect could improve the use of antibiotics in poultry farms as well as reduce human exposure to antibiotic residues and bacterial resistance to antibiotics.

172-179

Authors: Sakr OA

Increasing bird growth is a crucial demand for all poultry producers. This occurs by the genetic improvement of the existing breeds and by improving the feeding management. The present study investigated the impact of Alpha-Lipoic Acid (ALA) supplementation in the diet on performance, serum parameters, tibia bone composition, and the expression levels of growth-related genes in chickens. A total of 120 day-old broiler chicks (Cobb 505) were used and divided into four groups. The control group was fed on a basal diet without the ALA supplement. The birds in groups of A50, A100, and A200 were fed on the formulated diet supplemented with ALA at doses of 50, 100, and 200 mg/kg of diet, respectively for 35 days. Results indicated that ALA supplementation significantly improved the birds’ growth performance. This effect was associated with a marked upregulation of mRNA levels of GHR and IGFR and a significant downregulation of MSTN expression level. In addition, the ALA dietary provision caused a distinct improvement in liver function and bone efficiency. Thus, the improving effect of ALA on birds’ growth performance is mediated by modulating the growth-regulating genes. In conclusion, ALA could be used as a good growth-promoter in dietary supplements.

184-194

Authors: El-nabarawy AM

Poultry litter is used in fish farms as fertilizer thus integrated fish-duck farming is common in some areas of Egypt. Salmonella bacteria may be present in poultry litter and contaminate fish ponds and infect duck farms. To investigate incidence and prevalence of Salmonella infection in integrated duck-fish farms, 50 litter samples, 200 cloacal swabs from integrated duck farms, 60 liver samples from integrated duck farms and 69 water samples from the fish pond were collected. Results revealed the isolation and identification of 19 Salmonella spp. belonging to 14 different serotypes (4 isolates from litter, 2 isolates from fish pond water, 8 isolates from cloacal swabs of ducks and 5 isolates from ducks liver). Fifty, one-day-old Pekin ducks were experimentally infected with five chosen Salmonella serotypes (S. Bargny, S. Tshingwe, S. Uganda, S. Kentucky, and S. Enteritidis). The results from experimental infection revealed clinicopathological findings including degeneration and necrosis in the liver, lymphoid depletion and macrophage infiltration in the spleen and enteritis. Mortality ranged from 28.6% in S. Bargny, S. Enteritidis and S. Kentucky and increased to 42.9% in S. Uganda and reached up to 100% in S.Tshingwe. Body weight gain decreased by 16% in S. Uganda and exceeded to 23.9% in S. Kentucky and decreased by 31% in S. Bargny and S. Enteritidis as compared to the control group. Feed conversion ratio was recorded and ranged from 5.1, 5.11, 4.98, 5.15 and 4.02 in S. Bargny, S. Uganda, S. Kentucky, S. Enteritidis, and control group, respectively. In conclusion, different species of Salmonella can affect integrated duck-fish farms and cause high mortality as well as a decrease in feed intake, feed conversion ratio, and body weight gain.

203-213

Authors: El-Maghraby AS

Staphylococcus aureus is considered one of the most important pathogens causing septic arthritis in poultry with significant economic losses. This study aimed to evaluate the efficacy of a locally prepared S. aureus vaccine against staphylococcal arthritis in poultry. Out of 78 samples collected from infected chickens showing clinical signs bumble foot, 10 field isolates were detected and confirmed phenotypically by culturing, Gram staining, biochemical and molecular identification to be S. aureus in prevalence of 12.82%. Molecular identification of clumping factor A (ClfA) and blaZ genes of S. aureus isolates revealed that the PCR amplification with ClfA and blaZspecific primers conducted with genomic DNA resulted in products of approximate size 638 bp and 833 bp, respectively. Phylogenetic tree for S. aureus ClfA virulence gene partial sequences was generated using maximum likelihood, neighbour joining and maximum parsimony in MEGA6. It showed clear clustring of Egyptian isolated strain (S. aureus ASM strain) and different S. aureus strains uploaded from GenBank. Sequence identities between the Egyptian isolated strain (S. aureus ASM strain)and different S. aureus strains uploaded from GenBank revealed 99.5% to 100% homology. Also, there was identity and homology in S. aureusblaZgene nucleotide sequence in the Egyptian isolated strain (S. aureus ASM strain)and the different S. aureus strains uploaded from GenBank revealed 96.1% to 98.9% homology. Phylogenetic tree for S. aureusblaZβ-lactamases resistant gene partial sequences showed clear clustring of the Egyptian isolated strain (S. aureus ASM strain)and different S. aureus strains uploaded from GenBank. The results of humoral immune response revealed that the geometric mean antibody values against locally prepared S. aureus vaccine measured by indirect hemagglutination test increased from 1st week post vaccination gradually till reached maximum level (322.5) at 6th week post boostering. The results showed an increased humoral antibody production in vaccinated group that was capable of preventing establishment of new S. aureus infection in vaccinated group compared to control group. The mortality rates in unvaccinated group was higher than that of vaccinated group were (42.5%, vs. 7.5%) at 1st and 2nd week post challenge (39.1% vs. 5.4%). The protection % in challenge assay of the prepared S. aureus vaccine was (92.5% and 87.5%) at 1st and 2nd week post challenge respectively. It could be concluded that the prepeared vaccine was safe, potent and protect birds against S. aureus infection

223-234

Authors: El Nabarawy AM

Natural contamination of feedstuffs with mycotoxins is considered a major problem affecting the poultry industry in Egypt. Accordingly, this study aimed to compare the ability of different antimycotoxin compounds in the control of mycotoxicosis caused by naturally contaminated diet in broiler chickens. A total of 180 day-old broiler chicks were divided into six groups (30 chicks each group) and kept for a 5-week experimental period. Group 1 was kept as control negative (non mycotoxicated or treated), while group 2 was kept as a positive control (mycotoxicated only). Groups 2-6 were fed ration contaminated with 11 ppb aflatoxins, 3.9 ppb ochratoxins, and 4.2 ppm zearalenone. Groups 3-6 were kept in mycotoxicated ration until 2 weeks of age when clinical signs and lesions were suggestive for mycotoxicosis. Groups 3, 4 and 5 were treated with biological, antioxidant, immunostimulant compounds; respectively. Biological, antioxidants and immunostimulant compounds were given in the drinking water. In group 6, ration was treated with formaldehyde vapor. Performance parameters including body weight, feed consumption and feed conversion rate were recorded weekly. Clinical signs, mortalities and lesions were observed. Serum samples were collected for determination of immunological profile to infectious bursal disease (IBD) virus vaccine. Moreover, liver, kidney and bursa of Fabricius were collected for histopathological examination. Muscles and liver tissue samples were collected for determination of aflatoxins residues. Results revealed significant improvement in performance parameters in treated groups in comparison to non-treated mycotoxicated group, however, antioxidants-treated birds showed the highest performance. The severity of clinical signs and lesions were reduced in the treated chickens compared to non-treated mycotoxicated ones. Significant modulation in immune response toward IBD virus was observed in all treated chickens compared to non-treated mycotoxicated chickens. Histopathological examination of organs of control mycotoxicated birds showed severe degenerative changes which became mild in bursa of Fabricius while returned to normal histological structure in liver and kidney. Residues of aflatoxins in tissues of all groups exceeded the permissible limit with high levels in mycotoxicated control positive group. In conclusion, water treatments with some antimycotoxin agents like biological, antioxidants and immunostimulant compounds greatly counteracted the adverse effect of the naturally contaminated ration with different mycotoxins.

247-249

Authors: Elkamshishi MM

The vaccine is one of the most important biological products used in the poultry industry, thus it must be safe, potent, and effective. This work presents the results of a large-scale diagnostic survey performed in Egypt to study hygienic epidemiology and how vaccination may affect the viral circulation in the field. This study aimed to detect bacterial contamination in live poultry vaccines imported to Egypt during 2018. In this study, 285 consignments poultry vaccines, including 114 consignments live vaccine, 103 consignments recombinant vaccines, and 68 consignments killed vaccines (imported through Cairo airport during 2018) were examined for bacterial contamination. The vaccines were imported from USA, Italy, France, Spain, Mexico, and China. Bacterial contamination with Salmonella species was detected using the VITEK 2 system in two samples (1.8%) (IB+HB1 vaccine imported from Italy and ILT vaccine imported from USA).

263-277

Authors: Helal SS

Alternative strategies are applied for the prevention of Necrotic Enteritis (NE) particularly after the global perspective of the antibiotic ban. This study was a trial for NE control depending on vaccination by toxoid and/or immune enhancement by Nutri-lac IGA administration (a liquid mixture of fermentation by-product 80%, lactic acid 10%, and formic acid 10%). A total of 120 one-day-old broiler chicks were randomly divided into four groups (30 chicks/group). Group 1 (G1) was vaccinated with C. perfringens type A toxoid; Group 2 (G2) was toxoid-vaccinated and immune enhanced by Nutri-Lac IGA; Group 3 (G3) was immune enhanced by Nutri-Lac IGA and Group 4 served as control. Each group was subdivided into two subgroups, one subgroup was challenged with C. perfringens and the other was kept unchallenged. No significant clinical signs were detected in birds and mortality was observed only among challenged controls. The thin and friable intestinal wall was observed in all challenged broilers which extended to ulceration only in the challenged control group. No prominent histopathological findings related to NE were detected except in challenged controls and the highest protection against the NE-histopathological changes vividly appeared in the challenged G2 group. Significant increase in body weight of G1 and G2 groups after challenge in comparison to before challenge. While body weight of chickens in both G3 and challenged control groups was lower after challenge than before challenge. Pre-challenge ELISA results indicated no significant difference in immunoglobulin (Ig) Y titer among all groups after the first dose of vaccination, while significant differences appeared after the booster dose. The highest IgY titer was recorded in the G2 group, followed by G1, and G3 group. Post-challenge ELISA results showed a highly significant difference among all challenged subgroups. The highest IgY titer was recorded in the G1, followed by G2, and G3 group. The serum neutralization test also demonstrated the highest mean antibody titer in G1 and G2 groups. In conclusion, this study confirmed that a toxoid-immunostimulant combination is effective in NE prevention only when it is accompanied by the absence of NE predisposing factors.

285-291

Authors: Shedeed EA

Salmonella infection is a critical veterinary and medical problem worldwide and is a major issue in the food industry. Non-typhoidal Salmonella is known as an important pathogen causing gastroenteritis. The Outer Membrane Proteins (OMPs) of Gram negative bacteria are significant for virulence, host immune responses and drug therapy targets. Enhanced diagnosis of live poultry colonized with Salmonella species is required to avoid foodborne diseases. The present study was based on molecular characterization of OMPs among four Salmonella serovars (S. Typhimurium, S. Enteritidis, S. Kentucky and S. Anatum) using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The OMPs profiling showed more than 70 protein bands ranged in size from 208 kDa to below 16 kDa which were detected using Total Lab 1D 12.2 software. All Salmonella strains had a band at 54-60 kDa, 45-53 kDa, 36-39 kDa and 26-31 kDa. Eleven strains exhibited a band at 41-46 kDa and 33-35 kDa. Nine strains had a band at 61-69 kDa. Eight strains exhibited a band at 135-145 kDa and 72-79 kDa. Seven strains had a band at 108-123 kDa and 83-91 kDa. In the Western blot analysis, the prepared hyperimmune anti serum of each Salmonella serovars reacted with the 35 kDa protein band. It is concluded that the identification of novel immunogenic proteins would be useful in developing ELISA-based diagnostic assays with a higher specificity.

299-325

Authors: Abd El-Lattief A

Salmonella Typhimurium is the most Salmonella serovar causing acute gastroenteritis and diarrhea. Serovar 1, 4, [5], 12: i:- is considered a monophasic variant of S. Typhimurium that threaten public health. Fifty-eight serologically confirmed Salmonella strains were investigated by PCR using 16S rRNA and fliC genes. All 58 strains harbored 16S rRNA while 21 strains harbored fliC gene that included S. Typhimurium (12), S. Kentucky (6), Salmonella variant strain serotype 1, 4, [5],12:i:- (1), S. Lagos (1), and S. Kedougou (1). A duplex TaqMan real-time PCR was performed for differentiating between biphasic S. Typhimurium and monophasic serovar 1, 4, [5], 12:i:- using fljB1, 2 and fliB/IS200 in the fliA-fliB intergenic region. Ten out of twelve S. Typhimurium harbored fljB 1, 2, while Salmonella variant strain serotype 1, 4, [5], 12:i:- lacked this gene. Thirteen strains (12 S. Typhimurium and the variant strain serotype 1, 4, [5], 12:i:-) were positive for fliB/IS200 that is a specific gene for S. Typhimurium (biphasic and monophasic ). The result of duplex TaqMan real-time PCR indicated that 10 S. Typhimurium strains were biphasic while two S. Typhimurium strains and the variant strain serotype 1, 4, [5], 12:i:- lack fljB1,2 and had fliB/IS200 were monophasic S. Typhimurium. It is noticed that prolonged subculture and repeat phase inversion method leads to the formation of flakes that in turn cause wrongly serotype identification, therefore, real-time PCR is rapid and can be used for identifying and differentiating between biphasic and monophasic S. Typhimurium.