Evidence Suggesting that the Deposition of Pigments into Yolks is Independent of Egg Production: Enhanced Pigmentation of Yolks by Feeding Hens with Canthaxanthin Biosynthesized by Microbials

Pigments in the diet affect yolk colors. Due to variations in both the bioavailability of pigments in chickens and their amounts occurring in the feed ingredients, concern about egg quality arises in terms of yolk color. In this study, the effects of pigments, produced through cell culture in the laboratory, on yolk colors were determined for 4 weeks in laying hens receiving one of the 6 dietary treatments: control diets containing 1) no synthetic pigments (CON); 2) canthaxanthin (4 ppm) purchased from BASF (BASF); 3) cultured cells so that the diet had canthaxanthin at 4 ppm (CX); 4) cultured cells so that the diet had lycopene at 30 ppm (LP); 5) canthaxanthin (4 ppm) that was purified from cultured cells (SPCX); or 6) lycopene (30 ppm) that was purified from cultured cells. Relation between deposition of pigments into yolks and egg production was also tested. Yolk color of eggs from chickens fed dietary CX was significantly enhanced, which was slightly but significantly below that of BASF. Results from other treatments were lower than those of CX. Deposit rates of pigments into yolks were: BASF > CX > SPCX > LP > SPLP. The amounts of pigments, with the exception of SPLP, in feed were not changed during the storage for 4 weeks at $25^{\circ}C$. Egg production rates varied among treatments during the initial phase of the study but became relatively uniform at the later stage, except for CON and LP groups. The results of the present study indicate that the deposition of pigments into yolks is independent of egg production.

난황 내 색소의 축적은 산란율과 무관함을 제시하는 증거: 균체가 생성하는 Canthaxanthin의 급여에 의해 강화된 난황의 착색

산란율이 착색제의 난황 축적률에 미치는 영향을 조사하기 위하여 본 연구에서는 미생물 균주를 통해 합성된 몇 가지 형태의 착색제를 산란계에게 급여한 후 그들의 난황 착색 능력을 비교하였다. 약 70주령의 하이라인 브라운 산란계 37 수를 6개의 처리구로 나누어 다음의 사료를 4주 동안 급여했다. 1) 착색제를 포함하지않은시판사료(CON); 2) 시판사료에 BASF 사가 제조한 canthaxanthin을 4 ppm 첨가(BASF); 3) 사료 중 canthaxanthin이 4 ppm 포함되도록 canthaxanthin 균체를 시판 사료에 첨가(CX); 4) 사료 중 lycopene이 30 ppm 포함되도록 lycopene 균체를 시판 사료에 첨가(LP); 5) canthaxanthin의 합성 균체로부터 정제된 canthaxanthin 이 시판 사료에 4 ppm 첨가(SPCX); 그리고 6) lycopene의 합성 균체로부터 정제된 lycopene이 시판 사료에 30 ppm 첨가(SPLP). BASF Color Fan으로 측정된 난황의 착색도는 BASF > CX > LP 급여구 순이었다. 실험 초기에 산란율은 처리구간 차이가 있었지만 실험의 종반에 80% 정도였고, 특히 BASF와 CX처리구간에 차이는 없었다. 색소의 난황 축적률은 BASF > CX > SPCX > LP > SPLP 순이었고, 착색제의착색효율["BASF Color Fan score"를 "계란 1개에 포함된 색소의 양(${\mu}g$/egg)"으로 나눈 값]은 SPCX > SPLP > CX > BASF > LP 순이었다. SPLP를 제외하고 착색제들은 $25^{\circ}C$에서 4주 동안 비교적 사료 주의 함량이 변하지 않았다. 따라서 본 연구의 결과는 착색제의 난황 축적률은 산란율에 독립적임을 시사한다.