ABSTRACT
The aim of this study was to determine the hematological profile and specific immunity of laying hens with the addition of oil extracts of lycopene or astaxanthin to the diet. The study used High Line W36 chickens that were vaccinated against Newcastle disease, infectious bronchitis, avian rhinotracheitis and egg drop syndrome. It was found that the addition of lycopene (20 mg/kg) and astaxanthin (10 mg/kg) for 30 days did not affect the hematological profile of laying hens. Increasing the content of lycopene to 40 and 60 mg/kg or astaxanthin to 20 or 30 mg/kg of feed for 30 days reduced the number of leukocytes and hemoglobin in the blood compared to the control, which received an equivalent amount of refined sunflower oil in the diet. Lycopene and astaxanthin supplements, regardless of dose and duration of administration, did not affect the titer of antibodies to Newcastle disease, infectious bronchitis, avian rhinotracheitis, and egg drop syndrome in serum of vaccinated laying hens. The obtained data can be used to justify the optimal dose and term of feeding of lycopene or astaxanthin supplements in the development of a model of carotenoid enrichment of chicken egg yolks.
ABSTRACT
The antigenicity of three inactivated emulsified associated vaccines against viruses of chicken infectious bronchitis (IB), Newcastle disease (ND), and egg drop syndrome-76 (EDS-76) based on the oil adjuvant ISA-15 (O/W) was comparatively studied: (1) reference vaccine (IB+ND+EDS-76/ISA-15);(2) experimental vaccine (IB+NB+EDS-76/ISA-15-Nano) with a nanoscale-dispersed oil phase obtained by the use of a high-pressure homogenizer;(3) similar nano-scale vaccine (IB+NB+EDS-76+CoAA/ ISA-15-Nano) additionally supplemented with a copolymer of acrylic acid (CoAA). The in vivo tests of the vaccines on the chicks evidenced that both nano-scale vaccines enhanced the immune response in vaccinated chicks as compared to the reference vaccine and that supplementation with CoAA resulted in the highest postvaccinal antibody titers.