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Effects of different dietary ratios of linoleic acid to a- linolenic acid on productive performance, immunity of laying hens and egg yolk fatty acid composition
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Abstract: This study was carried out to determine the effects of various dietary ratios of linoleic acid to a-linolenic acid on productive performance, immune response of laying hens and fatty acid composition in egg yolk. Soybean oil was used as source of linoleic acid (LA) and linseed oil was used as source of a-linolenic acid (LNA). A total number of 150 hens + 15 cocks were randomly equally divided into five experimental groups with three replicates (10 hens + 1 cock/ replicate). The experimental hens were assigned to 1 of 5 diets that had LA to LNA ratios 2:1, 4: 1, 6:1, 8:1 and 10: 1, respectively by changing the proportions of soybean and linseed oils. The studied criteria were productive performance, egg quality and yolk fatty acid composition. Also some blood immunological parameters (WBC's, RBC's, IgG, IgM, Hb, and PCV %) and immune response against SRBC's, ND and AVID titers. Some serum constituents (AST, ALT and alkaline phosphates enzymes), in addition some serum, liver and yolk constituents (total lipids, triglycerides, total cholesterol and LDL-cholesterol) were studied Results obtained indicate that LA to LNA ratios 6:1 and 8:1 had the highest numerically values of egg mass and egg production rate and the best feed conversion values. The ratio 6:1 had significantly decreased yolk weight and increased yolk index. Egg shell quality did not influence by different dietary LA to LNA ratios. The ratios 4:1 and 6:1 had significantly increased yolk content of long-chain FA's (AA, EPA and DHA) and total n-3 PUFA's. While, total n-6 PUFA's (P < 0.05) was gradually increased in yolk by increasing dietary LA to LNA ratio. Adding LA to LNA ratio 2:1, 4:1 or 6:1 in laying hens diet caused changes in the fatty acid profile of yolk and produced eggs have ratio of n-6 to n-3 total PUFA's 5:1, 5.5:1 or 6:1, respectively. The ratios 4:1 and 6:1 had significantly reduced total lipids, triglycerides, total cholesterol and LDL-cholesterol levels in maternal hens (serum, liver. and yolk). The ratios of LA to LNA did not significantly affect on AST and ALT enzymes but ratio 4:1 significantly increased alkaline phosphates concentrations. The ratio 6: 1 increased serum concentrations of IgM, Hb and PCV%. as well count of immune cells (WBC's and RBC's) and antibody production against SRBC's, ND and AVID, significantly. It could be concluded that, LA to LNA ratio 4: 1 or 6:1 in laying hen's diets are acceptable and recommended to improve the productive performance and immune response. In addition produce eggs have low triglycerides and cholesterol; it means that more healthy eggs for consumer especially people who suffering from heart diseases.
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| Publication year |
2012
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| Pages |
163-188
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| Availability location |
معهد بحوث الانتاج الحيوانى- شارع نادى الصيد- الدقى- الجيزة
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| Availability number |
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| Organization Name |
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| City |
الاسكندرية
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| serial title |
Egyptian Poultry Science
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| ISSN |
1110-5623
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| Author(s) from ARC |
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| Agris Categories |
Animal physiology - Nutrition
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AGROVOC
TERMS |
Cholesterol.
Egg yolk.
Fatty acids.
Immunity.
Layer chickens.
Linoleic acid.
Performance testing.
Production.
Triglycerides.
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| Publication Type |
Journal
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