اثرات سطوح مختلف تفاله خشك گوجه‌فرنگي بر عملكرد توليد مرغ‌هاي تخم‌گذار و كيفيت داخلي تخم‌مرغ در دما و زمان‌هاي مختلف نگهداري

Effects of different levels of dried tomato pulp on production performance of layers and egg internal quality traits during different storage times and temperatures

زمينه مطالعاتي: سطوح مختلف تفاله گوجه‌فرنگي در جيره پس از تولك مرغ‌هاي تخم­گذار مورد بررسي قرار گرفت. هدف: اثرات سطوح مختلف تفاله خشك گوجه­ فرنگي در جيره پس از تولك مرغ­ هاي تخم گذار بر عملكرد توليد و كيفيت داخلي تخم­مرغ در دما و زمان­ هاي مختلف نگهداري مورد ارزيابي قرار گرفت. روش كار: آزمايشي با 120 قطعه مرغ تخم‌گذار لگهورن پس از دوره تولك‌بري (78 هفتگي) در قالب طرح كاملاً تصادفي با 3 تيمار و 5 تكرار و 8 مرغ در دو قفس مجاور طراحي شد. جيره­ هاي آزمايشي شامل جيره غذايي شاهد(بدون تفاله گوجه­ فرنگي، صفر درصد) و سطوح 7/5 و 15 درصد تفاله گوجه فرنگي بود كه اثرات آن به مدت 8 هفته بر عملكرد توليدي پرندگان مورد ارزيابي قرار گرفت. درپايان دوره، 6 تخم­مرغ از هر تكرار در دماهاي 4 و 25 درجه سانتيگراد و زمان­هاي 1، 7 و 30 روز پس از توليد، نگهداري و كيفيت داخلي آنها تعيين شد. نتايج: استفاده از تفاله گوجه­ فرنگي تا سطح 15 درصد جيره غذايي مرغ­هاي تخم­گذار به مدت 8 هفته، درصد توليد تخم­مرغ روز مرغ، وزن تخم ­مرغ، گرم تخم­مرغ توليدي، مصرف خوراك و ضريب تبديل خوراك را بطور معني­داري تحت تاثير قرار نداد. نتايج نگهداري تخم ­مرغ در دما و زمان­هاي مختلف نيز نشان داد كه اثرات اصلي سطح تفاله گوجه ­فرنگي و زمان نگهداري تخم ­مرغ بر واحدهاو معني­دار بود (0/05

Introduction Tomato, one of the most popular vegetable used in food preparations is used to processing and production of tomato juice . During processing, large amount of pulp including seeds is produced which can be used in poultry feeding . Tomato pulp is known as a protein source in poultry diets but its seeds have strong antioxidant such as ß - carotene and lycopene ) Friedman et al, 2000) . Some researchers used tomato pulp up to 19 - 20% in layi ng hen diet and reported no significant changes in performance criteria (Salajegheh et al, 2012; Calislar and Uygu, 2010). The positive effect s of antioxidant compounds in some plants such as tomato on egg quality have been reported previously by some rese archers (Sahin et al, 2008 ; Uuganbayar, 2005 ). It have been documented that layer hens meet some oxidative attacks during force molting , cause to depressing production performance and egg internal quality traits (Siegel 1980), therefore, adding antioxidan t to diet s , may be useful after force molting phase (Skrivan et al, 2010). T he aim of this study was to evaluate the effect of different levels of tomato pulp in post molted laying hens on egg production performance and egg internal quality traits during different storage times and temperatures . Material and m ethods O ne hundred and twenty W - 36 White leghorn laying hens in post - molting phase (78 week) were assigned to 3 treatments with 5 replications and 8 birds each based on completely rand omized design. Some dried t omato pulp s w ere obtained from a commercial tomato processor in West Azarbaijan province . After chemical analysis of dry matter, crude protein, crude fiber and also determining TME n of tomato pulp, three isocaloric and isonitroge nous diets formulated to have 0 , 7.5 and 15 % of tomato pulp and fed to birds for 8 weeks . Egg production, egg weight, feed consumption, egg mass and feed conversion ratio were recorded weekly and reported as monthly or total period. Six egg samples from each replicates of control group and group having best production performance ( 15 % tomato pulp ) collected and stored in different temperatures (4 and 27° C) and duration times (1 day, 1 week and 1 month after production) then evaluated for their internal quality traits such as albumen pH, Haugh unit and yolk index. Results and d iscussion Results showed that using tomato pulp up to 15 % of diet could not aff ect egg production of post - molted hens during 8 weeks of production (P>0.05) . Similar findings have been reported by Calislar and Uygu (2010), who used up to 20 % tomato pulp in layers diet, but reported no significant effect on egg production performance, but some researchers (Jafari et al, 2006) reported decrease in egg production performance of birds fed 15% tomato pulp. In agreement with Salajegheh et al. (2012), e gg weight, egg mass, feed intake and feed conversion ratio of hens were not affected significantly by use of tomato pulp up to 15 % in diet. Results of egg quality traits during different times and temperatures showed that main effects of usage levels and storage duration times were significant (P<0.05) on albumen pH and Haugh unit . With increasing tomato pulp usage level, Haugh unit increased a nd Haugh unit decresed when egg storage duration time incresed. I nteraction effect of tomato pulp usage level and duration time w ere significant ( P <0.05 ) on albumen pH and Haugh unit . Although with increase storage duration time , albumen pH increased and Haugh unit decreased, but among eggs stored 30 days in room temperature, the Haugh unit of treatments fed diet containing 15 % tomato pulp, was significantly (P<0.05) higher compared to ones fed diet with 0% tomato pulp. Conclusion: It is po ssible to use 15 % tomato pulp in post - molting diets of layer hens with no significant adverse effects on production performance and due to significant interaction effect of tomato pulp usage level and duration time on albumen pH and Haugh unit, the use of 15 % tomato pulp could restrict fluctuations of egg internal quality traits during storage.