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English :
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Studies on the effect of certain feed-additives on the performance of broilers and layers fed aflatoxicated feed
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Arabic :
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دراسة تأثير بعض الإضافات الغذائية على الاداء الانتاجى لبداري التسمين والدجاج البياض المغذاة بعلف ملوث بسموم الافلاتوكسينات
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| Abstract |
Allatoxin is the most carcinogenic agent known in the poultry diets which leads to mortality and economic loss, besides its dangerous carry over via poultry meat into human beings causing human liver carcinoma. For these reasons, two experiments were designed aiming to study the possibility of removing or alleviation of toxicity caused by aflatoxin diet, namely by adding some dietary supplementations.
On -day- old broiler "Hubbard" chicks were used in the first experiment, whereas 20 weeks old laying hens "Lohman Brown" were used in the second experiment. All the experimental birds were fed on commercial diets after the addition of aflatoxin at a dose of l mg/kg diet, except the control group which left without addition. The first experiment lasted 4 weeks followed by 2 weeks, as treatment and withdrawal periods, respectively. In the second experiment birds received aflatoxicated diet for 6 week (2 weeks before egg production and 4 weeks during egg production) followed by 2 weeks withdrawal.
The broiler chickens of first experiment included 10 groups as follow:
I-Control diet without any additives (T1)
2- T1 + 1 mg aflatoxin (AF)/kg diet (T2)
3- T1 + 0.5 g methionine /kg diet (T3).
4- T2+ 0.5 g methionine /kg diet (T4).
5- T1 + 1 mg selenium/kg diet (T5).
6. T2 + 1 mg selenium/kg diet (T6).
7-T1 + 20 mg virginiamycin /kg diet (T7).
8-T2 + 20 mg virginiamycin /kg diet (T8).
9- T1 + 3 g HSCAS/kg diet (T9).
10- T2 + 3 g HSCAS/kg diet (T10)
While the layer experiment contained 4 groups.
1- Control diet without any additives. (T1)
2- T1 + 3 g HSCAS/kg diet (T2)
3- T1 + 1 mg AF/kg diet (T3)
4- T3 + 3 g HSCAS/kg diet (T4)
These studies was conducted to estimate the following criteria:
. Weekly individual body weight, feed consumption and feed conversion.
. Egg production, egg weight, egg mass and egg quality.
. Slaughter test for organs and glands weights.
. Serum biochemical values and enzymatic activities.
. Immune response to ND disease in vaccinated chickens.
These studies revealed followine results:
* Body weight:
All aflatoxic diets led to decrease in body weight of chickens, comparing with the control received non aflatoxin diet, whether during the treatment period or even during the withdrawal time. Addition additives (methionine, selenium or virginiamycin) to the basal diet without aflatoxin improved significantly the body weight comparing with the control group,
while these additives (methionine, selenium, virginiamycin or HSCAS) with aflatoxic diets improved significantly the body weight in comparison with group fed aflatoxic diet alone. But, HSCAS as a feed additive gave the best results than methionine, selenium and virginiamycin.
In laying hens aflatoxic diet resulted in lowering body weight than
the control group particularly T3, while T4 adding 0.3% HSCAS to
aflatoxic diets diminished the adverse effect of aflatoxic diets on laying
body weight.
* Feed consumption:
Aflatoxic groups in both broiler chicks and laying hens consumed lower feed than the control group throughout treatment and recovery periods. Supplemented feed additives to aflatoxic diet reduced aflatoxicosis and increased feed consumption compared with aflatoxic diet alone. Aflatoxic hens were recovered after 2 weeks.
* Feed conversion:
Feed conversion ratio was impaired in aflatoxicated groups when compared with the control groups in either broiler chicks or hens even during the withdrawal period.
The addition of feed supplements (methionine, selenium or virginiamycin) to non aflatoxicated diet was improved the feed conversion ratio comparing with the control. Also, these additives (methionine, selenium, viginiamycin or HSCAS) to aflatoxic diets improved feed conversion than aflatoxic diets alone in both broiler chicks and hens.
* Egg production:
Egg production was decreased in all aflatoxicated groups during treated period. The severity effects were alleviated by adding HSCAS. During recovery period, these effects were gradually diminished.
* Egg weight and egg mass:
Both egg weight and egg mass were decreased in all aflatoxicated groups during treated and recovery periods. The severity effects was also diminished in group fed 0.3% HSCAS with aflatoxic diet. During recovery period, these effects were gradually diminished.
* Egg quality:
Aflatoxic diets decreased yolk and shell weight, yolk height and shell thickness, while increasing albumin as a percent of egg weight and yolk color, there was no effects on egg shape and albumin height. Adding 0.3% HSCAS alleviated effects of aflatoxic diet on yolk, albumin and shell weight as a percent of egg weight and shell thickness. At the end of recovery period, (2 weeks) egg qualities of aflatoxicated . groups were recovered except for yolk, albumin and shell weight, the improvement was non significant.
* Relative organ and gland weights:
Relative organ weight of liver was enlarged, while bursa of Fabricius and thymus glands were atrophied in aflatoxicated group. But no effect on spleen weight during treated or recovery periods was reported. The severity effects were alleviated by adding methionine, selenium, virginiamycin or HSCAS to aflatoxicated diets. After 2 weeks recovery period, the liver, bursa of Fabricius and thymus glands were recovered while the liver especially for group fed aflatoxic diet without additives was continuously affected.
* Serum constituents:
Aflatoxin affected the serum constituents in both broiler chickens and laying hens during treated and recovery periods with the same trend of the influence. There were decreases in values of total protein, albumin, globulin cholesterol, triglycerides, calcium and uric acid, while estimated values for alkaline phosphates, GPT, GOT, GGT and creatine kinase was increased. The severity effects diminished by adding methionine, selenIum, virginiamycin or HSCAS to aflatoxic diets. After 2 weeks recovery period, the serum constituents especially for group fed aflatoxic diet without additives were affected continuously with less severity.
*The immune response to ND vaccines [Haemagglutination-Inhibition (HI)
The mean titers of HI antibody response to ND vaccines was not ignificantly affected in aflatoxicated groups. Although, the little improvement In, antibody response to ND vaccines by adding methionine, selenium, virginiamycin or HSCAS) with or without aflatoxin was reported.
In conclusion, aflatoxin is very toxic natural poison which threaten not only the poultry production industry but also human health in Egypt.
Dietary supplements (methionine, selenium, virginiamycin or HSCAS) were highly beneficent improved the chicks performance without flatoxin, and may be beneficent in partial detoxification of aflatoxic diets. Yet, the prophylaxis is still the best way than the decontamination or detoxification.
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| Publication year |
2000
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| Pages |
193p.
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| Availability location |
مكتبة معهد بحوث الانتاج الحيوانى- شارع نادى الصيد- الدقى - الجيزة
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| Availability number |
744
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| Organization Name |
Animal Production Research Institute (APRI)
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| Country |
Egypt
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| Department |
Poultry Nutrition Research Department
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| Author(s) from ARC |
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| Agris Categories |
Animal feeding
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AGROVOC
TERMS |
Additives.
Aflatoxins.
Broiler chickens.
Economic analysis.
Egg production.
Feeds.
Layer chickens.
Mortality.
Performance testing.
Poultry meat.
Toxicity.
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| Publication Type |
PhD Thesis
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