| Titles |
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English :
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The bioefficacy of thyme in practical layer diets varying in their energy content
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Arabic :
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تقييم اضافة الزعتر الى العلائق التطبيقية للدجاج البياض المختلفة في محتواها من الطاقة
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| Abstract |
Ninety Bovans White laying hens 25 weeks old were used in this study to evaluate the bioefficacy of thyme, as a natural feed additive, in layer diets varying in their metabolizable energy content. The hens were randomly distributed into 6 groups of 15 birds each and assigned randomly for one of the experimental diets. Two experimental diets were formulated using linear programming to be isonitrogenous (18.5% CP) but varying in their metabolizable energy content. The first experimental diet contained low energy level (2700 Kcal/Kg diet) and was considered as negative control (E1), while the second experimental diet contained 2900 Kcal/Kg diet, according to the strain catalog recommendation (E2). Thyme was used to substitute 0, 1.5 or 3% of the total feed mixture of each of the experimental diets. Accordingly, a total of 6 experimental diets were used in (2X3) factorial design.
Ground thyme contained 8.19% moisture, 91.81% dry matter (DM), 80.84% organic matter (OM), 10.65% CP, 3.17% EE, 17.29% CF, 10.97% ash and 49.22% NFE (on air dry basis), indicating its nutritious value in addition to its active medicinal substances. Regardless of the diet energy, addition of thyme decreased (P<0.05) both of average egg weight (g) and feed intake (g/day/bird), while improved feed conversion, significantly and egg production rate, insignificantly. Thyme at 1.5% of low energy diets improved egg production, egg mass, feed conversion and the viability of the birds, as compared to their control (96.6 vs. 88.9 %, 53.4 vs. 51.5 g, 2.0 vs. 2.2 and 100 vs.73%, respectively). No significant differences (P<0.05) were found between low energy level (E1) and catalog recommendation (E2). However, recommended energy diets (E2) Improved (P<0.05) egg weight and viability of the birds, as compared with E1 diets Neither external nor internal egg quality values were affected, significantly (P<0.05), the treatments. Thyme at 1.5%, regardless of diet energy, scored the best digestion coefficient values when compared with the control (without thyme supplementation) or 3% thyme. Addition of this level to low energy diets improved digestion coefficient and nitrogen balance values, except EE value, when compared with either their control (El) or the control of recommended energy diets (E2). This treatment, also improved both economical efficiency and relative economical efficiency, when compared with the control of recommended energy diet (0.52 vs. 0.42 and 124 vs. 100, respectively). The results also indicate that it is not reasonable to use thyme at 3% of the laying hen diet, not only from economic point of view but also because it had no improving effects on laying hen performance, as compared with 1.5%.
The previous results suggest to add not more than 1.5% thyme to low energy diet of laying hens to improve their performance, bird viability and economic efficiency.
further studies are recommended to test lower levels (less than 1.5%) of thyme on haying hen performance.
Keywords: thyme, natural feed additives, metabolizable energy, laying hen.
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| Publication year |
2005
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| Pages |
237-248
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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 |
Animal Production Research Institute (APRI)
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| serial title |
Egyptian Journal Nutrition and Feeds
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| ISSN |
1110-6360
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| Author(s) from ARC |
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| External authors (outside ARC) |
عادل زكى محمد سليمان
جامعة القاهرة
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| Agris Categories |
Animal feeding
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AGROVOC
TERMS |
Energy value.
Feed conversion efficiency.
Feed intake.
Layer chickens.
Thyme.
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| Proposed Agrovoc |
natural feed additives;egg weight;egg production rate;
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| Publication Type |
Journal
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