계란의 비린내 강도는 가금류의 종류와 개인의 인식에 따라 다르지만 여러 요인에 의해 발생할 수 있다. 특히 트 리메틸아민(TMA)이 원인으로 밝혀졌다. 주목할만한 점은 리보플라빈이 TMA를 무취의 트리메틸아민-N-옥사이드로 전환시키는 역할을 하는 효소인 플라빈 함유 모노옥시게 나제 3의 활성을 증가시킬 수 있다는 점이다. 본 연구는 난황의 TMA 함량을 분석하여 비린내에 대한 기여도를 평 가하고, 비린내를 방지하는 방법을 개발하는 것을 목적으 로 하였다. 고체상 미세추출-기체 크로마토그래피/질량 분 석법을 사용하여 리보플라빈이 강화, 보충된 사료를 먹인 암탉의 난황에 있는 휘발성 화합물을 감지하고 정량화했다. 또한 샘플 간 휘발성 물질의 상대적 함량을 비교하기 위해 전자코를 이용하여 상관관계 연구를 수행하였다. TMA는 콜린이 함유된사료를 섭취한 가금류의 난황에서 고농도로 검출되었지만 리보플라빈이 보충된 사료를 섭취한 가금류 에서는 검출되지 않았다. 전반적으로, 이 연구는 리보플라 빈이 TMA를 포함하여 계란에 존재하는 휘발성 물질의 양 과 품질에 영향을 미친다는 것을 시사한다. 이러한 발견 이 계란의 비린내를 줄이는 것은 물론 품질 향상에 기여 하기를 기대한다.
An experiment was carried out to assess the effect of feed selenium-lysine (Se-Lys) supplementation on milk compositions and serum biochemical indices in Saanen dairy goats in Korea. A total of twelve 36 months old Saanen lactating dairy goats (47±6.21 kg) fed the similar dry matter intake twice a day at 2% of BW (DMI) (10.9% moisture of concentrate and 19% moisture of roughage), milk yield (2.5 kg/d) and parity (2) were randomly selected and subjected for the present study, divided into two groups with six goats in each group. The goats in the control group received rice hulls (10 g/ day) only, and did not receive Se-Lys; goats in the treatment group were fed 0.06 g of Se-Lys with 10 g of rice hulls every day before feeding roughage for six weeks. The milk sample was collected every week, and its compositions were analyzed. The results of the present study showed that there is no significantly increased milk production in Se-Lys treated group goats when compared with control group goats. But, Se-Lys treatment significantly increased the milk protein content (3.98±0.16%), fat (3.72±0.27%), lactose (4.07±0.14%), total solids (12.51±0.28%) and urea (14.42±1.45 mg/dl) content as compared to the control group goats (p<0.05). The somatic cell counts (207,740±28.81 cells/ml) were significantly lower in the Se-Lys treated group than in the control group (p<0.05). Also, the results of the current study showed that supplementation of Se-Lys were significantly decreased the blood biochemical indices of IL-6 (34.34±6.04 pg/ml), TNT-α (0.56±0.22 ng/ml), MDA (5.07±1.03 ng/ml), GPx-1 (9.07±5.17 ng/ml), sCD4 (2.64±1.02 ng/ml) and sCD8 (5.08±2.08 ng/ml) level when compared with without addition of Se-Lys group dairy goats (p<0.05). On the other hand, the selenoprotein P (1,580.18±127.62 ng/ml) level was significantly higher in Se-Lys supplemented group than in the control group (p<0.05). Based on the study results, it was concluded that feed Se-Lys supplementation may improve milk yield with positively improved protein, fat, lactose, total solids, urea content, and biochemical indices without negative effects on milk production traits.
Antibiotics have been used to prevent disease, promote growth rate, and improve feed efficiency. However, the use of antibiotics in livestock has been restricted worldwide due to problems such as bacterial resistance. Therefore, probiotics among alternatives to antibiotics have gained attention in the livestock feed industry these days. This study was conducted to investigate the effects of dietary supplementation with probiotic 379D on safety, growth rate, and feed efficiency. In this study, bacterial strain 379D was isolated from soil and identified as a Bacillus sp. according to 16S rRNA sequence analysis. In an in vitro test, in-gel activity assay and antimicrobial susceptibility test were conducted to evaluate 379D. In an in vivo study, 379D was administered at concentrations of 0.1% and 1% to broiler chickens for 28 days. The results of in-gel activity assay and antimicrobial susceptibility test showed that strain 379D had broad spectrum antimicrobial activity. Furthermore, no adverse 379D-related effects were observed in 0.1% and 1% groups. Feed efficiency was higher in the 379D-treated groups than in the control group. In conclusion, 379D is expected to be used as a safe alternative to antibiotics in a feed supplement and will improve feed efficiency in broiler chickens.