Sunset Yellow FCF (SY), used frequently in ready-made foods, cosmetics, and the pharmaceutical industry, may cause many health problems. This study is intended to evaluate the morphological and cellular effects of SY on the embryonic chicken immune system throughout incubation. Babcock white leghorn eggs were randomly divided into four groups. Besides a control group, there were three treatment groups which received a single injection of 200, 1,000, or 2,000 ng of SY into the air sac just before incubation. The eggs were opened on the 10ᵗʰ, 13ᵗʰ, 16ᵗʰ, and 21ˢᵗ days of incubation. Samples of the bursa of Fabricius, thymus, and spleen were taken from embryos. Serial sections of 5 μm thickness were stained with histological methods and routine histological procedures were performed. An increase in the spleen volume was determined as the hatching time of the chicks approached. The highest eosinophil ratio was found in the SY₁,₀₀₀ and SY₂,₀₀₀ groups (P < 0.05), where the most significant change was developmental retardation in the thymus. In the bursa of Fabricius, there was less lymphocyte accumulation and eosinophilic cell infiltration with increasing doses. It was concluded that in ovo administered SY has undesired effects on embryonic development of the bursa of Fabricius, spleen, and thymus, and on spleen volume.

The efficacy of four infectious bursal disease virus (IBDV) vaccines including intermediate (D78) and intermediate plus (228E, IBD-Blen and Bursa-Vac+) were compared in priming vaccination of 10 days commercial old male layer chicks. There were different parameters were measured for testing these vaccines including; the immunogenic efficacy, the effect on performance, organ (bursa, spleen, and proventriculus) body weight index as well as histopathological examination of bursa, spleen, proventriculus and thymus. Chick was received a dose of 102 EID50 from one IBDV vaccine out of 228E, IBD-Blen or Bursa-Vac+, while D78 dose was 104 EID50. The results cleared out that all the tested vaccines passed through the maternal derived antibodies 2480.133 + 156.3. All vaccines stimulate antibody formation as measured by ELISA test. The used vaccines not affect markedly body weight and feed intake, as there were no significant differences between the control group and the vaccinated ones in the mean body weight and the feed conversion rate. Furthermore, the bursa: body weight index of vaccinated groups were generally less than those of control one at all intervals, while the spleen and proventriculus: spleen: body weight index of vaccinated groups was higher than control on at the end of the observation period. The used vaccines induced histopathological changes in bursa, spleen , proventriculus and thymus glands. These results indicated that all tested vaccine are of value in vaccination of commercial chicks from vaccinated breeders

Newcastle Disease virus (NDV) and Avian Influenza virus (AI) are represent a great negative significant causing severe economic losses and increased mortalities worldwide. Newcastle disease (ND) and Avian Influenza (AI) vaccination were targeting to lower the losses from mortality, reduce the viral load in the environment as well as eradication of positive cases. Many immunostimulants had been used to improve the immune response of vaccinated chickens. The current study was designed to compare the effect of different immunostimulants on chick's immune response to bivalent ND with AI-H5N1 oil vaccine. One hundred and ten, 1- day old Baladi chicks, At the 1st day of life (0 day) 10 birds were sacrificed to obtained individual blood samples for serum to determine maternal antibodies (MDAbs) to both AI and ND. Rest of birds (100 chicks) were divided into 5 equal groups (1-5); each 20 chicks. All chicken groups were vaccinated against ND with eye drop instillation of HB1 vaccine. While, at the 9th day birds of the groups 1-3 and 5 were given H5N1 vaccine by S.C injection, birds of group 4 were lifted as non AI vaccinated control. The used immune stimulants under test were given to groups 1, 2, and 3 as follows Lector, Superimmune and Imuvral; respectively. All the groups were subjected to daily observation with recording of feed intake, weekly body weight gain and total FCR, Weekly serum samples were collected, for serological examination, and the results showed high antibody titers, low mortality rates and better body performance in the groups treated with immunostimulants than the other groups which were not treated with the immunostimulants

OBJECTIVE To determine effects of in ovo administration of a probiotic on development of the intestinal microbiota of 2 genetic lineages (modern and heritage) of chickens. SAMPLE 10 newly hatched chicks and 40 fertile eggs to determine intestinal microbiota at hatch, 900 fertile eggs to determine effects of probiotic on hatchability, and 1,560 chicks from treated or control eggs. PROCEDURES A probiotic competitive-exclusion product derived from adult microbiota was administered in ovo to fertile eggs of both genetic lineages. Cecal contents and tissues were collected from embryos, newly hatched chicks, and chicks. A PCR assay was used to detect bacteria present within the cecum of newly hatched chicks. Fluorescence in situ hybridization and vitality staining were used to detect viable bacteria within intestines of embryos. The intestinal microbiota was assessed by use of 16S pyrosequencing. RESULTS Microscopic evaluation of embryonic cecal contents and tissues subjected to differential staining techniques revealed viable bacteria in low numbers. Development of the intestinal microbiota of broiler chicks of both genetic lineages was enhanced by in ovo administration of adult microbiota. Although the treatment increased diversity and affected composition of the microbiota of chicks, most bacterial species present in the probiotic were transient colonizers. However, the treatment decreased the abundance of undesirable bacterial species within heritage lineage chicks. CONCLUSIONS AND CLINICAL RELEVANCE In ovo inoculation of a probiotic competitive-exclusion product derived from adult microbiota may be a viable method of managing development of the microbiota and reducing the prevalence of pathogenic bacteria in chickens.

This study was carried out to determine the immunomodulating effect of β-glucans and mannan oligosaccharide (MOS) on the immune response of chickens to Newcastle disease vaccine. The results showed that birds received β-glucans and MOS having higher average body weights values and significantly higher ND HI antibody titer than the other non medicated groups. Thymus, spleen and bursal indices of control negative showed significantly lower values than vaccinated medicated and non-medicated groups. Both total and differential leukocytic and lymphocytic counts showed significantly higher in medicated group than other groups. Liver function test showed lower AST and ALT in medicated group than other groups. Results of challenge test with NDV confirmed that MOS and B glucans immunostimulant improved protection rate by 15% in medicated than non- medicated ones. In conclusion MOS and B glucans can be given to chicken to improve both body weight and protection against VV NDV challenge that predominated in Egypt.

The haematochemical, histopathological and immunological studies were carried out on chicks experimentally infected with the low pathogenic avian influenza virus (LPAIV) (A/Turkey/CA/209092/02) H5N2. Eighty SPF one day old chicks were serologically negative for specific antibodies against avian influenza virus. The birds were devided into 2 groups, birds in the 1st group were inoculated with the virus via the intraocular and intranasal routs, while the other group was kept as non-infected control. Five birds were sacrificed from both groups at 5, 7, 10, 15, and 21 days post inoculation. Sera and heparinized blood as well as tissue specimens from lung, liver, spleen, trachea, small intestine and bursa of Fabricius were collected. Estimation of haemagglutination inhibition antibodies response against AI, liver and kidney function tests, rate of proliferation of T-lymphocyte were conducted. The experimentally infected birds showed general signs of illness with 80% morbidity and 6 % mortality. There was an increase in aniline aminotransferase (ALT) and asparate aminotransferase (AST) enzymes which reflected liver damage. High urea and creatinine values were also detected in sera of infected birds which proved kidney dysfunction. There was no significant proliferation of T-lymphocyte among examined groups. Very low haemagglutinating inhibiting (HI) antibodies was detected in infected birds. Histopathological examination displayed conspicuous depletion and necrosis of the lymphocytic aggregation in the organs of the haemobiotic system (Bursa of Fabricius, spleen and thymus). Such finding may decipher the low sero-conversion as well as the unproliferation of T-lymphocyte. The necrobiotic changes in liver and kidney sections in addition to congestion and edema elucidate the increased parameters in their functions. Also, the epithelial hyperplasia of the tracheal mucosa and the sloughing in the lining mucosal epithelium are indicative for the epithelio-tropism of the AI virus.

The objective of this study was to compare the effects of 3 diet formulations containing different protein sources (animal, plant, and a combination of animal and plant) on the colonization of Campylobacter jejuni in the gastrointestinal tract of broiler chickens. A freshly isolated strain of C. jejuni (biotype IV, serotype HS O:21, O:29, HL untypable) from a broiler chicken was used to infect 3-day-old chicks that had been free of C. jejuni; 0.5 mL of an inoculum containing 108 colony-forming units was administered orally. Shedding of the organism was studied, and C. jejuni in the ceca, jejuni, and crop were enumerated by quantitative culture. The isolates recovered from the birds during the study period of 35 d were characterized and confirmed as C. jejuni by the use of standard methods and underwent biotyping, serotyping, antimicrobial susceptibility testing by disk diffusion and the E-test, and flagellin gene typing. A cyclical pattern of shedding of C. jejuni was observed in all the birds. Colonization was highest in the ceca. The ceca of birds receiving plant-protein-based feed had significantly less colonization then the ceca of birds receiving the other types of feed, whereas the differences in colonization of the jejuni and crops were not significant. Characterization by biotyping, serotyping, and flagellin gene typing showed that 95% of the recovered isolates were identical to the strain used for infecting the chicks. However, with the Lior-HL typing scheme, 74% of the recovered isolates were HL untypable. Antimicrobial resistance testing did not reveal significant differences between the infecting strain and the recovered isolates among the different feed groups.

The left ovary of chicken embryos was removed and incubated in culture medium with a thymidine analogue, bromodeoxyuridine (BrdU), in vitro. In addition, fertile chicken eggs were injected with BrdU via the extraembryonic vessels and incubated for 24 hours. The ovaries were then processed for immunohistochemical localization of calbindin-D28K (a 28-kd vitamin D-dependent calcium-binding protein) and BrdU. Calbindin-D28K was detected in the germinal epithelium and in cells surrounding the oogonia and oocytes (future granulosa cells) of the embryonic chicken ovary. However, Brdu was observed in the nucleus of the oogonia and oocytes of the chicken embryonic ovaries. Comparison of the 2 adjacent sections, immunostained for calbindin-D28K and BrdU consecutively, indicated that BrdU, the marker for cell proliferation was not detected in calbindin-D28K-containing cells, namely, germinal epithelium and future granulosa cells, in the ovary of chicken embryos. These results suggested that calbindin-D28K-containing cells in the ovary were not in the process of cell division during the 24-hour incubation of chicken embryos.

Immunoreactivity for 28 kd vitamin D-dependent calcium-binding protein (calbindin-D28k) has been localized in the germinal epithelium and cells surrounding oogonia and oocytes (future granulosa cells) of developing and growing ovaries of chicken embryos. The protein first appeared prominently in the germinal epithelium of the developing left ovary in 8-day embryos. At the twelfth day of incubation, cells surrounding oogonia and oocytes reacted intensely for calbindin-D28k. The number and intensity of calbindin-D28k-containing cells increased in both types of cells as the embryos further developed. Calbindin-D28k remained in the germinal epithelium throughout the study period observed (up to 10 weeks). However, the protein was present transiently in the future granulosa cells. It gradually decreased after hatching, and was virtually absent from granulosa cells in a 10-week old chicken. Compared with the known process of onset of sexual development, these results indicated possible involvement of calbindin-D28k in the early phases of oogenesis in chicken ovaries.

The B1 strain of Newcastle disease virus (NDV-B1), which is nonpathogenic for newly hatched chickens, killed embryos when it was used to inoculate chicken eggs at embryonation day 18. Treatment of NDV-B1 with an alkylating agent, ethylmethane sulfonate (EMS) markedly reduced the pathogenicity of the virus for 18-day-old chicken embryos. Eggs inoculated with the modified virus (NDV-B1-EMS) hatched, and the virus was isolated from lungs and spleen of 1-day-old chickens. The hatched chickens developed antibody to NDV and were protected against challenge exposure (at 4 weeks of age) with a highly virulent GB-Texas strain of NDV. Presence of maternal antibody to NDV in embryonating eggs did not influence the protective ability of NDV-B1-EMS, which also induced protective immunity when administered to 4-week-old chickens. The 50% protective dose of NDV-B1-EMS in maternal antibody-negative and -positive embryos was calculated to be 10.77 and 17.70 embryo 50% lethal doses, respectively. Results of the study indicated that NDV-B1-EMS may be used as an embryo vaccine to protect chickens against Newcastle disease.