chickens

Distinguishing the variables that control craving and examining the interaction between them can improve the efficiency of livestock breeding, genetic modification, and drug treatments of obesity-related complications. Hence, in the current study, we investigated the interaction between neuropeptide Y and melanocortinergic systems with brain-derived neurotrophic factor (BDNF) in regulating broilers' feed intake. The present study was conducted on 264 broiler chickens in 6 experiments. In experiment 1, chickens received intracerebroventricular (ICV) infusion of BDNF (7.5, 15, and 30 μg) after 3 h of food deprivation. BIBP-3226 (NPY1 receptor antagonist, 1.25 nmol), BDNF (30 μg), and BDNF + BIBP-3226 were administrated in the second treatment. Experiments 3-6 were similar to treatment 2, except birds were infused with BIIE 0246 (NPY2 receptor antagonist, 1.25 nmol), CGP71683A (NPY5 receptor antagonist, 1.25 nmol), SHU9119 (MC3/MC4 receptor antagonist, 0.5 nmol) and MCL0020 (MC4 receptor antagonist, 0.5 nmol) instead of BIBP-3226. Then, cumulative meal intake was recorded for 2 hours. Based on observations, BDNF injection (15 and 30 μg) caused significant hypophagia at all test times (p<0.05). The co-infusion of NPY2 and NPY5 receptor antagonists with BDNF did not affect BDNF-induced hypophagia (p>0.05), while the infusion of NPY1 receptor antagonist + BDNF caused a significant strengthening of this effect (p<0.05). Also, despite the lack of significant effect of MC4 receptor antagonist + BDNF administration on the appetite-reducing effect of BDNF (p>0.05), simultaneous infusion of MC3/MC4 receptor antagonist and BDNF suppressed hypophagia (p<0.05). Finally, it appears that MC3/MC4 and NPY1 receptors mediate BDNF-induced hypophagia in 5-day-old broiler chickens.

In recent years, much attention has been focused on the development of inactivated fowl aviadenovirus (FAdV) vaccines in the poultry industry against inclusion body hepatitis (IBH) outbreak. It was the objective of this study to determine the safety and immunogenicity of inactivated FAdV vaccine following different inactivation time intervals in commercial broiler chickens. FAdV isolate, UPM1137 was treated with binary ethyleneimine (BEI) at 20 hours (h), 24h, 28h, 32h and 36h. All treated isolates were furthered tested for safety test in specific pathogen free (SPF) chicken embryonated eggs (CEE) followed by safety and immunogenicity trial in SPF chickens. Based on the current findings, it was demonstrated that the isolate treated at 20h, 24h and 28h induce more than 80% mortality in SPF CEE, while, no mortality was recorded for isolate treated at 32h and 36h. In SPF chickens, neither clinical signs, nor gross and histological lesions were recorded throughout the trial after inoculated with isolate treated at 32h and 36h. The isolate treated at 32h and 36h are completely inactivated and safe in commercial broiler chicken. Based on ELISA findings, chickens vaccinated with inactivated FAdV at 32 hours (h) (group B) induce high antibody response compared to that inactivated FAdV at 36h (group A) at day 14 and 28pi. At day 28pi, mean antibody titer for booster groups in group A and B were significantly high (p < 0.05) compared to the control group. It showed that both FAdV vaccine using inactivated inoculum at 32h and 36h are safe and immunogenic in broiler chickens typically at day 28pi following booster vaccination. It was concluded that the optimal period of FAdV inactivation was 32 hours and highly suitable to be used for future vaccine formulation.

Chicken production is quickly rising due to the low associated costs and the capability of poultry to convert nutrients into biological protein along with chicken meat accounting for 30% of all animal protein eaten by humans. Despite advances in poultry production, parasitic illnesses in laying hens remain a problem. Farm birds reared in semi-intensive and free-range systems are more prone to parasite infections due to the absorption of polluted water and food from scavenging behaviors and waste droppings. In this study, the effects of Ascaridia galli infection on the immune response and liver function of two laying hen lines are compared, and their infection resistance is determined. In total, 50 laying hens at eight weeks of age were used (25 Lohmann brown-classic and 25 Lohmann lsl-lite), and each line was divided into two groups: an infected group (n=15), which was orally infected with a single dose of 500 A. galli embryonated eggs, and a control group (n=10), which was given normal saline. After four and eight weeks, blood was collected from the wing vein to assess the serum's AST, ALT, total protein, and IgY levels. The results demonstrated that the infected Lohmann brown-classic and Lohmann lsl-lite chickens presented significantly increased (P≤0.05) AST, ALT, and IgY, compared to the respective control group. Moreover, Lohmann brown-classic hens presented a significantly increased (P≤0.05) IgY concentration four weeks after infection, compared to Lohmann lsl-lite hens. From our results, it can be concluded that genetic variation plays a crucial role in the immune response against A. galli, where the Lohmann brown-classic line was found to be more resistant, compared to the Lohmann lsl-lite line.

Pathogenic Escherichia coli is one of the world’s most important zoonotic foodborne pathogens and poses a serious threat to public health. We examined the prevalence, virulence genes, and antibiotic resistance profile of Shiga toxin (Stx)-producing E. coli (STEC) isolated from broiler chickens in the Kafr El-Sheikh governorate, Egypt. A total of 410 samples (230 cloacal swabs, 180 internal organs) were collected to isolate E. coli. A total of 29 (7.07%) E. coli isolates were recovered and identified, and 18 of them harbored Stx genes (stx). Out of 18 isolates, five (17.24%) carried the stx1 gene, five (17.24%) carried the stx2 gene, four (13.79%) carried both stx1 and stx2 genes, and four (13.79%) carried stx1, stx2, and eaeA genes. Overall, complete antibiotic resistance was observed against amoxicillin, ampicillin, cefpodoxime, and cefoperazone; high resistance was observed against ampicillin/sulbactam, nalidixic acid, cefuroxime, aztreonam, ciprofloxacin, ceftriaxone, chloramphenicol, sulfamethoxazole/ trimethoprim, and ceftazidime; moderate resistance against gentamicin; low resistance against cefoxitin; lower resistance was detected against norfloxacin, cefotetan, and amikacin; and the lowest resistance against imipenem. All E. coli isolates demonstrated multidrug resistance against at least four antibiotic classes. Out of 29 E. coli isolates, STEC accounted for 18 isolates, of which the O78, O26:H11, O128:H2, O1:H7, O119:H6, and O91:H21 serogroups were predominant. All E. coli isolates were multidrug resistant and therefore pose a potential public health concern as these virulent, resistant strains may spread to humans. Thus, high levels of hygiene and biosecurity are required by chicken handlers to decrease the danger of infection spreading to humans.

This study aimed to assess the possible feeding behavior alterations by central interactions of cholecystokinin (CCK) and glutamatergic systems in neonatal chickens. In experiment 1, chickens received intracerebroventricular (ICV) administration of saline and CCK (CCK4; 0.25, 0.5, and 1 nmol). In experiment 2, birds were ICV injected with saline, CCK8s (0.25, 0.5, and 1 nmol). In experiment 3, chickens received the ICV injection of saline, CCK8s (1 nmol), MK-801 (15 nmol), and co-injection of the CCk8s+MK-801. Experiments 4-7 were performed similar to experiment 3, except for chickens that were injected with CNQX (390 nmol), AIDA (2 nmol), LY341495 (150 nmol), and UBP1112 (2 nmol) instead of MK-801. Subsequently, the total amount of the consumed food was determined. According to the results, the ICV administration of CCK4 (0.25, 0.5, and 1 nmol) could not affect the food intake in chickens (P>0.05). The ICV injection of the CCK8s (0.25, 0.5, and 1 nmol) led to a dose-dependent hypophagia (P<0.05). Moreover, hypophagia induced by CCK8s decreased by the co-injection of the CCK8s+MK-801 (P<0.05). These results showed that the hypophagic effects of the CCK on food intake can be mediated by NMDA glutamate receptors in layer-type chickens.

Salmonella Enteritidis (SE) infection in poultry is one of the most important concerns in poultry. Virulence and pathogenicity of the SE isolates from Iran have not been well studied so far.

In the present study, three Salmonella Enteritidis (SE) isolates were compared with a standard SE strain (PT21) for virulence in one-day-old layer chicks. All of the isolates were supposed to be virulent because of carrying a large-sized virulence plasmid.

Fifty day-old layer chicks (LSL strain) were divided into five groups of 10 chicks and raised in separate cages until 14 days of age. All three SE isolates were cultured in brain-heart infusion (BHI) broth to reach a concentration of approximately 1010 CFU/ml. The challenged groups included three groups inoculated with three SE isolates (A20, S32, S34) and one group inoculated with SE PT21 as positive control. One group was raised as negative control without receiving any bacteria. Any mortality or morbidity observed in any group was recorded. Samples were taken from liver, jejunum and cecum at days 2, 4, 6, 9 and 14 days of age, cultured for SE isolation, colony counting and histopathological examinations.

All challenged groups showed mild to severe diarrhea in all birds and some birds were listless especially in the first week. No signs were seen in the control group. Two mortalities occurred in challenged groups. Salmonella Enteritidis was detected in all samples until the end of experiment. The colony count showed less (100 to 1000 times less) SE in liver compared to that of cecal samples. Histopathological findings also were compatible with symptoms and bacteriological results.

We concluded that all three SE isolates were able to colonize in the digestive system of layer chicks leading to mortality or at least lower performance compared to healthy chicks

Campylobacter is recognized as a major cause of foodborne gastroenteritis in humans in many countries and may be transferred from animals to humans. The consumption of chicken meat is identified as a major cause of Campylobacter infection in humans.

To find out the contamination rate of chicken meat with Campylobacter, the antimicrobial resistance (AMR) pattern, and the virulence-associated genes of theisolates.

Ninety packed chicken meat from 7 main poultry slaughterhouses in Shiraz were analyzed for Campylobacter spp. isolation through microbiological methods. Specific primers were used for the identification of the Campylobacter isolates on species level by polymerase chain reaction (PCR). Antibiotic resistant profiles were determined using the disc diffusion method based on Clinical and Laboratory Standards Institute (CLSI) standards. All the isolates were screened for 7 virulence-associated genes, namely cdtA, cdtB, cdtC, cadF, pldA, cgtB, and virB11 by PCR.

Out of 90 chicken meats, 26 (28.9%) Campylobacter spp. have been isolated. Resistance to ciprofloxacin (CIP), nalidixic acid (NA), and cefixime (CFM) was observed in all the isolates. Resistance to trimethoprim/sulfamethoxazole (SXT), tetracycline (TET), ampicillin (AMP), and chloramphenicol (CHO) was 80.8%, 88.5%, 76.9%, and 30.8%, respectively. Multidrug resistance (MDR) phenotype was observed in 80.8% of the Campylobacter isolates. All the isolates were positive for cdtA, cdtB, cdtC, and cadF genes. pldA and cgtB were detected in 65.4% and 15.4% of the isolates, respectively.

In this study, the presence of several virulence genes and an alarming level of MDR in Campylobacter spp. isolates were reported. Particularly, resistance to CIP and TET should be highlighted, since both are key drugs for the treatment of human campylobacteriosis.

In order to investigate the incidence of macroscopic Ectoparasites of free-range domestic chickens and pigeons in Qom province, 300 free-range domestic chickens and 300 pigeons from Central district, Salafchegan, Jafariyeh, Kahak, and Khalajastan were randomly selected and studied from December 2016 to September 2017. 200 poultry were selected from Central district, and 100 ones from each of the other districts under study were put under careful investigation. Of the 300 domestic chickens, 202 (67.33%) were infected and 98 (32.67%) were free of external parasites. Moreover, out of 300 pigeons, 218 (72.66%) were found to be infected, while 82 (27.34%) were free of external parasite infection. The highest infection percentage of domestic chickens and pigeons in Salafchegan district were 90% and 84%, respectively, and the lowest percentage of domestic chickens infection was observed in Central district as 43% and the lowest infection rate was reported in Jafariye as 66% . As the findings revealed, in each district, the highest contamination was observed in Salafchegan (87%) and the lowest was related to the Central district (44%). The genus and species of parasites isolated from domestic chickens were Menopon gallinae, Menacanthus stramineus, Goniodes dissimilis, Lipeurus caponis, and Cuclotogaster heterographus. Argas persicus, a fowl tick, was also isolated from domestic chickens. The fly larvae were also found and isolated in several nests. The highest contamination was related to Menopon gallinae (69%), and the least was Goniodes dissimilis (5%). In addition, Menopon gallinae, Lipeurus caponis, and Menacanthus stramineus and Argas persicus (a small soft-bodied tick), were isolated from the pigeons under study. The highest infection was found to be Menopen (53%) and the lowest was related to Menacanthus (14%).

Ornithobacterium rhinotracheale (ORT) has been identified as one of the respiratory bacterial pathogens in turkey and chicken flocks. Four live birds displaying severe torticollis were submitted from a 13-week-old commercial broiler breeder chicken flock located in Mazandaran province. These birds were suspected to pasteurellosis by the farm veterinarian. No other marked gross lesion except emaciation was seen. Histopathologic examination of the brains showed mild to moderate meningeal vasculitis، perivascular cuffing with lymphocytes، degeneration and necrosis of purkinje cells in the cerebellum. Viral culture of the brains especially for Newcastle disease and avian influenza viruses was negative. Bacterial culture of the brains onto the blood agar revealed pure growth of Ornithobacterium rhinotracheale. In this study molecular confirmation of ORT by using of a very specific polymerase chain reaction (PCR) was carried out. Amplification products of a 784 bp region of the 16S rRNA gene of ORT confirmed the bacterium identification. This is the first field case of ORT isolation from the brain of commercial chickens in Iran. These data suggest that this bacterium should be considered in differential diagnosis in cases of avian nervous signs. Further studies are necessary to confirm if ORT is a primary pathogen in such cases.

Satureja hortensis is a popular herb in most regions of the world with leaves used as seasoning. Evidence shows that this plant contains phenolic components such as thymol and carvacrol with a relatively wide spectrum of antimicrobial activity. This study aimed at evaluating the efficacy of S. hortensis plant powder as an alternative to antimicrobial growth promoters in broiler diets. The plant was bought in sufficient quantity from the district of Yasouj، Iran and was dried and ground into powder. A total of 140 unsexed 1-day-old Arbor Acers breed broiler chicks were housed and fed a starter diet up to 18 days of age. The birds were then randomly divided into two groups and reared under similar conditions. Chickens received either normal grower (from 18 to 35 days of age) and finisher (from 36 to 50 days of age) diets without S. hortensis (group I) or a similar diet containing one percent plant powder (group II). Statistical comparison of average body weights at various time intervals showed that chickens in group II (1930 ± 29 g، n=63) were significantly (P<0. 05) heavier than the birds in the control group (1837 ± 25 g، n=62). The average body weight of males in each group (2075 ± 42 g، n=20 and 2143 ± 40 g، n=22 for groups I and II، respectively) was also greater than those of the females (1724 ± 34 g، n=42 and 1808 ± 30 g، n=41 for groups I and II، respectively). Although feed conversion ratio was slightly less in group II (1. 95)، it was not substantially different from that in group I (2. 02). It is concluded that S. hortensis might be a potential growth promoter in poultry.

Ornithohac/erium rhino/rachea/e (ORT) is a relatively rceently diseovered bacterium. which it is associated with respiratory diseases, Tracheal samplcs from carcasses of 100 roultry tlocks submitted to Razi Institute were examined for ORT isolation. Ali these tlocks were affected with respiratory disorders. Colonies of ORT were detected after 24h of incubation and identification of ORT isolates were carried out based on the biochemical and serologie al charaeteristics. Fitiy-nine isolates From broilers, broiler breeders, and layer Ilocks were idcntilied as ORT and analyzed for serotyping. The isolates were identified as serotype A. using standard • antisera againsl ORT anligens in rapid slide agglutination, agar gel precipitation and immunodot tests. The identification of the species was confirmed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis of whole cell proteins. High similarity ofprotein profiles of the isolates was observed. These preliminary results establish that ORT serotype A is associated with outbreaks ofrespiratory diseases in commercial poultry.

Î II prell.:nt against reecnt virulent strains or in/ectious bursal disease virus (IBDY), a local isolaLe of the virus was propagated in bursal tissue, l(lfIllali/.ed and used I(lr vaccine production. An experimental vaccine adjll\anted hy oil ISA-70 was prepared and compared with a commercial IBDY-NDY inactivatcd vaccine. A single injection or the two vaccines proteeted chickens against mortality hut the oil adjuvanted bursal derived vaccine conli:rred a higher percent or bursal protection.