Bovine mammalian gland has biopotential in therapeutic protein production and could be used as a model in further lactation researches. In this study, we have isolated bovine mammary gland-derived epithelial cells (BMECs) from Korean Holstein dairy cattle and themselves show differential dynamic ability in in-vitro culture. BMECs enables to form lobulo-alveolar structure, express milk production related gene. Functional studies indicated that BMECs secret exogeneous antibacterial fragment-Bovine Lactoferricin B (bLfcin-B), which is inserted in PiggyBac system, and this bioactive fragment inhibits the growths of Escherichia coli and Staphylococcus aureus. These data demonstrated that BMECs open new scope in either bioactive fragment, heading to prevent the spread of mastitis or post-mastitis damage in dairy graze and could be an ideal bioreactor for antibacterial proteins.

본 연구는 지방산 함량 및 배합사료와 조사료 비율을 기초로 한 유기농 사료 급여가 홀 스타인 착유우에서 생산된 원유의 CLA 및 지방산 함량에 미치는 연구를 조사하기 위한 목 적으로 실시하였다. 총 290두의 홀스타인 착유우를 산차 및 유량에 따라 3개 group으로 나 누었다. 대조구는 C16:00, C18:2 그리고 SFA를 높게 설계하였고, 처리구 1은 C18:1, C18:2 그리고 UFA 함량을 높게 설계하였으며 처리구 2는 MUFA, C18:3 그리고 PUFA 함량을 높 게 설계하였다. 결과를 요약하면 다음과 같다. 유기농 원유 내 C16:0 함량은 처리구 2에서 가장 높은 것으로 나타났다(p<0.05). 그 이유는 반추위 내 미생물의 de novo 생합성 때문인 것으로 판단된다. 처리구 2의 C18:0 함량은 7.92%로 대조구(11.39%)와 처리구 1(10.88%)보 다 높았다(p<0.05). CLA 함량도 처리구 2가 처리구 1이나 대조구에 비하여 높은 것으로 나 타났다(p<0.05). 원유 내에서 검출된 대부분의 CLA는 착유우 유선조직내의 △9-desaturase에 의하여 합성된 것으로 판단된다. n-3/n-6 비율도 처리구 2에서 가장 높은 것으로 나타났다 (p<0.05). 본 연구 결과를 종합해 보면, 착유우에게 혼합 목건초 등을 급여하면 CLA, n-3 농 도는 증가하며 C18:0 농도는 낮아지는 것으로 조사되었다. 본 연구는 유기농 인증된 조사 료 및 농후사료를 이용하여 결과를 도출하였다. 그러나 유기농 사료를 사용할 경우에만 원 유 내 CLA 및 n-3 농도는 증가한다고 볼 수 없다. 원유 내 고농도의 CLA 및 n-3 지방산 생 산을 위해서는 반추위 미생물 및 유선세포의 지방 대사를 통한 CLA 생산 메커니즘에 대한 충분한 이해와 급여 사료 내 지방산 구성 등이 중요한 것으로 판단된다.

The present study was conducted to investigate effect of dietary protected amino acid on milk yield and composition in dairy cow using meta-analysis. Total 21 research papers were employed in analysis, and mixed model was used for the analysis of effects. Effect of protected methionine (PM) and combination of protected methionine and lysine (PML) were investigated under two different levels of dietary crude protein (CP, <18% and >18%). For performance of dairy cow, milk yield, milk composition including milk fat and protein content and yield and 4% FCM (fat corrected milk) production were used for analysis. In case of milk yield, a trend of increment was found at PM supplementation at low CP (P=0.055). However, the effect of PM at high CP was detected as not significant (P>0.05). In case of milk protein, inclusion of PM at low CP showed significant decrement (P<0.05). However, there was no significant effect of MP on milk protein at high CP (P>0.05). Supplementation of MP at high CP level showed significant increment of milk fat (P<0.05). MP supplementation represented significant increment of 4% FCM production (P<0.05) regardless of dietary CP levels. Effects of PML on milk yield and composition at both of low and high dietary CP were not significant in this study. However, it seem to be that there was a possible positive effect of MPL application at high dietary CP on performance of dairy cow.

The objective of this study was to evaluate the effect of GnRH or estradiol in a CIDR-based timed Al (TAI) protocol on follicular turnover, synchronized ovulation and pregnancy rates in Holstein cows. Cows were treated at random stages of the estrus cycle with an insertion of an intravigal progesterone (1.9 g) device (CIDR, Day 0) and either no other treatment (control group; n=10), injection of 100 ug fertirelin acetate (GnRH group; n=10) or 4 mg estradiol benzoate (estradiol group; n=10). Seven days later devices were removed and an injection of 25 mg PGF2a was administered. On Day 9, 100 ug GnRH was administered. Cows received a fixed-time insemination 16 h after injection of the GnRH.