Effect of feeding high levels of organic selenium on quail performance, physiology, new castle virus-immune response, and meat and egg quality

Abstract EN

Three hundred and four Japanese quail were used in two experiments to evaluate the effect of feeding high levels of Se ( 2.5,[5 and 7.5 ppm) in organic form at different growing periods on growth, immune response to New Castle virus, egg production and hatchability and its retention in meats and eggs.

In experiment I, one hundred and sixty chicks one-day old were divided into two main groups (80 each) for two trials, chicks of each trial were randomly allotted into equal four subgroups to test a basal diet and the three Se levels.

The specified chicks of the first trial were kept in a separate unit for immunological study, where chicks were vaccinated at seven-day old (Hitchner B1), and at four-week old challenged with Velogenic Viscerotropic New Castle disease virus, and the experiment ended at six week of age.

The chicks of the second trial joined the chicks of the second experiment in design.

In experiment II, one hundred and forty-four chicks, four-weeks old, were allotted into four groups.

Chicks of the second trial and second experiment at six-week age were moved to breeding cages where the breeding period extended for seven weeks consuming a breeding diet enriched with the same three mentioned Se levels.

Two basal diets were used, one for starting-growing chicks and the other for breeding pullets.

The Se content of the basal diet was found to be 0.24 and 0.17ppm for growing and breeding diets, respectively.

There were no significant differences in final body weight and FCR between control and the treatment groups during the growing period.

The level of GOT increased in groups fed 5 and 7.5 ppm Se/kg in trial 2, while there was no effect when Se fed at four-weeks old.

Results of uric acid and creatinine followed the same of GOT.

Concentration of T3 continued to increase as the dietary level of organic Se increased.

As to the effect on immunity the more Se concentration being fed, the more antibody titer and the higher relative level of protection.

In trial 2 of experiment I, egg production rate declined from 56.9 % in group 1 to 1.6 to 3.4 % in the other groups, also with no fertility or hatchability in the laid eggs and at the highest level fed (7.5 ppm) 40% of the hens died.

In experiment II, there were no significant differences in egg production, egg mass, fertility (except with those on 7.5 ppm) and hatchability of fertile eggs between control and treatment groups.

Selenium retained in muscle tissues continued to increase as the dietary level of Se increased.

The same pattern was reported in eggs.

The results confirm the ability of the quail to increase Se concentration in their products and to cope with large dietary levels.