# دراسات فسيولوجية و غذائية في الدواجن

[The effect of substitution of soybean meal 44% in the diet of Silver
Montazah chickens and hens by algae meal (40.59%) at levels of 0%, 25%
50% and 75%.
The obtained results are summarized as follows:
Live body weight:
-
There was an increase in live body weight (10.2-18.8%), (7.2-20.5%) and
(5.9-28.5%) at 25% algae meal level than other treatments.
-The highest body weight was at 25% algae meal level.
-The worst body weight was at 75% algae meal level.
Body weight gain:
-It
was noted that the best weight gain was in level 25% algae meal, as
well as in 50% algae meal at week 4 till 20 weeks of age, while at
level 75% the lower in body weight gain was detected.
Growth rate:
-There was an increase in growth rate at level 25% algae meal at weeks 2
till 6 weeks of age than other treatments (T1, T3, andT4).
-Increasing algae meal increased growth rate at weeks 7-20 weeks.
-Increasing algae meal decreased growth rate at weeks (0-4,5-8,9-12 and 0-12)
-75% algae meal was the worst in the growth rate.
Feed consumption:
-Increasing the level of algae meal decreased feed consumption -Birds fed 75% algae meal consumed less than other treatments.
Feed conversion:
- The best treatment in feed conversion was 25% algae meal level until 12 weeks of age.
-On contrary 75% algae meal level was the best in feed conversion from 16-20 weeks of age.
Sexual maturity:
- The age of sexual maturity decreased with the increased level of algae meal up to 50%.
- Birds need more time to arrive sexual maturity for T1 and T4 algae meal groups than T2 and T3.
- Body weight increased as algae meal increased up to 50% then body weight decreased at 75% algae meal group.
- Egg weight improved with increased the level of algae meal up to 50%.
Mortality
-Increasing the algae meal levels in the diet decreased percentage.
Carcass:
- There was increasing of heart, heart%, gizzard, spleen, spleen% and
G.L.H at Level 25% algae meal.
- The Liver and liver % was increased at level 50% algae meal.
- The dress was increased in chicks fed diet control and 25% algae meal (74.11, 70.34), respectively.
- Level 75% algae meal was the worst in all traits.
Second experiment:
Live body weight:
-Increasing the levels of algae meal from 0% to 75% significantly (p<0.05) decreased average body weight.
-Level at 25% algae meal was the best in body weight significantly
(p<0.05).
Feed consumption:
-Diets have nearly the same calories 2718.51, 2731.77, 2778.9 and
2792.69 respectively.
- The feed consumed for the three treatments were equal in 22 until 30 weeks of age.
-Daily feed intake decreased with increasing algae meal.
Feed conversion:
-Increasing the level of algae meal up to 50% improved significantly (p<0.05) feed conversion.
- T2 and T 4 (25 and 75%) algae meal had the worst feed conversion.
Egg number:
-Egg
production for 4 treatments through the 8 experimental 4-week periods.
It has been observed that increasing algae meal level from control (TI)
to 50% (T3) increased significantly average egg number.
-T4 (750/0) decreased significantly (p<0.05) average egg production/ hen/ period

-Birds fed control diet reached its peak production at 34-weeks of age.
-Level 50% algae meal reached its peak production at 30-weeks of age recording the highest level among other treatments.
-Birds fed 75% algae meal was inferior in egg number throughout the experimental period.
Egg weight:
- Increasing the level of algae meal increased egg weight up to 50% algae meal then decreased at level 75%.
-Level at 50% algae meal produced the high egg weight than other treatments
Egg mass:
-Level at 50% algae meal was the highest egg mass in all ages.
- Egg mass of birds fed control diets increased than other treatments (25% and 75%) algae meal.
-Level at 75% algae meal was the worst in egg mass.
Egg quality:
Egg weight
-At level 25% algae meal was highest than other treatments fu egg
weight
-Egg
weight at 30-34 weeks of ages increased significantly (p<0.05) while
at 38, 42 and 46 weeks of ages the increase was not significant.
Shell weight%:
-There was a significant difference of shell weight at ages 30,34,38,42 and 46 weeks of ages.
-Shell weight percentage was the heaviest at level (0 and 500/0) of algae meal.
-Level at 75% algae meal decreased shell weight percentage.
Shell thickness:
-No difference among shell thicknesses in all level at 30,34 weeks.
-Ages at 38, 42 and 46 weeks of age were significantly (p<0.05) in shell thickness.
-Shell thickness increased until level 50% of algae meal.
Haugh units:
-No significant differences among level 0%, 25%, 50% and 75% in all ages until 42 weeks of age.
- There were a significant differences (p<0.05) among all levels of algae meal at week 46.
Yolk color:
-
There were a significant differences (p<0.05) in yolk color in weeks
30, 34, 42 and 46 except 38 weeks of ages no significant difference of_
yolk
color was observed.
. Yolk color increased with increasing level of algae meal.
- 75% algae meal level was the highest in yolk color.
Shape index:
-There were no significant differences in shape index at weeks 30, 38, 42, and 46 weeks of age.
- There was a significant difference (p<0.05) in shape index at week 34.
Yolk index:
- There were no significant differences in yolk index at 30, 34, 36, 42 and 46 weeks of age.
-At level 0% the highest in yolk index while, at level 25% algae meal the worst in yolk index.
Fertility percent:
-Level at 50% algae meal was the best in fertility percent than other treatments.
-Level at 75% algae meal the worst in fertility percent.
Hatchability percent:
-It was noted that 50% algae meal increased hatchability (p<0.05) than other treatments (TI, T2 and T4).
Mortality:
-Mortality percent in all birds increased with increasing level of algae meal from 0% to 75% of Silver Montazah hens.
Carcass traits:
- The level of algae meal at 50% increased heart, liver, heart% and dress.
-Level 25% of algae meal increased spleen, spleen% G.L.H, gizzard, gizzard% than other treatments.
-Dressing percentage increased significantly at 25 % algae meal than
other treatments.
-Level 75% algae meal (T4) was the worst in all traits.
Blood samples:
-Increasing the level of algae meal in the diet did not affect total protein, albumin, globulin, NG ratio and glucose.
-Level at 75% algae meal decreased total lipids and cholesterol.
Digestibility coefficients:
-There were no significant differences (p<0.05) among treatments unless digestibility coefficients of dry matter.
-Level 250/0 algae meal the highest of dry matter than other treatments.
-Increasing
level of algae meal to 50 or 75% decreased significantly (p<0.05)
dry matter crude fiber, ether extract and nitrogen free extract
digestibilities.
-Digestibility coefficient of crude protein improved as the level of algae meal increased until 50%.
Physical and chemical analysis:
- Increasing the level of algae meal increased WHC, TEND and color significantly (p<0.05).
-Birds fed 25% algae meal had the highest pH than other treatments respectively.
-
Increasing the level of algae meal fed to different groups caused a
significantly increase (P<0.05) in the level of dry matter and crude
protein but decreased in ash and ether extract.
Economic efficiency:
-The total feed consumption was decreased by increasing algae meal level in the diet.
- The price/kg diet was decreased by increasing algae meal in the laYing diet.
-Net
revenue was the highest in case of diets contained 50% algae meal
(11.68 LE/hen), after which it decreased to reach (4.63 LE/hen in 25%
and 7.37LE/hen for 75%) algae meal.