The experimental work of the present study was carried out at
the Poultry Research Station, Poultry Department, Faculty of
Agriculture, Fayoum University. This experiment was conducted for
12 weeks to evaluate black seeds (Nigella sativa) (BS) as natural feed
additives for laying hens. A total number of 180 Hy- Line W- 36
laying hens 49 weeks old were used. The hens were randomly
distributed into 15 groups of 12 birds each. Each group was
subdivided into 12 replicates (one hen/replicate) and assigned
randomly for one of the experimental diets.
The experimental treatments were as follows:-
1. Hens were fed 14.75 % crude protein (CP) as a control diet (D1).
2. Hens were fed 13.25 % CP (adjusted methionine & lysine) (D2).
3. Hens were fed 13.25 % CP (non adjusted methionine & lysine) (D3).
4. Hens were fed 11.75 % CP (adjusted methionine & lysine) (D4).
5. Hens were fed 11.75 % CP (non adjusted methionine & lysine) (D5).
6. Hens were fed D1 + 1% black seeds. 7. Hens were fed D2 + 1% black seeds.
8. Hens were fed D3 + 1% black seeds. 9.Hens were fed D4 + 1% black seeds.
10. Hens were fed D5 + 1% black seeds. 11.Hens were fed D1 + 2% black seeds.
12. Hens were fed D2 + 2% black seeds. 13. Hens were fed D3 + 2% black seeds.
14. Hens were fed D4 + 2% black seeds. 15. Hens were fed D5 + 2% black seeds.
Results obtained could be summarized in the following:
1-There were significant differences among treatments in productive
performance except, egg weight (EW), crude protein conversion
(CPC) and live body weight gain (LBWG). Higher, dietary protein
levels had a positive effect on average egg production (EP) and
egg mass (EM) of layers. Average feed conversion (FC) and
caloric conversion ratio (CCR) improved significantly as dietary
protein levels increased. BS level had insignificant effects on
productive performance.
2-There were significant differences in egg quality among all dietary
treatments, except, yolk color and shell %. Yolk index% and
Haugh unit values significantly increased as dietary protein levels
decreased. Hens fed diet containing 2% BS had higher shell
thickness. Laying hens fed diet containing 1% BS had higher yolk
index. Hens fed diet containing 0.0% BS had higher shape index.
3-Black seeds supplementation had significant effects on serum
calcium, triglycerides, AST, total protein and phosphorus values.
Calcium and phosphorus values of serum significantly reduced as
dietary protein levels decreased.. Hens fed diet containing 1% BS
had higher ALT level.
4- No significant effects on immune response as a result to different
treatments supplementation was found in laying hen diets
throughout the whole experimental period except hemoglobin.
Level of CP% insignificantly affected all immune response except,
secondary immunity response, hematocrit% and white blood cells
values. Regarding to secondary immunity response, values
significantly increased as dietary protein levels decreased. There
were insignificant effects on immunity response during all
experimental period except, hemoglobin%. It is clear that
hemoglobin value was significantly decreased as black seed levels
increased.
5- Hens fed diet 3 gave the best economical and relative efficiency
values being 1.324 and 101.5%, respectively. The rate of change
in the relative efficiency varied between –50.87 to +1.50%.