A pregnancy diagnosis is an important standard for control of livestock’s reproduction in paricular dairy cattle. High reproductive performance in dairy animals is a essential condition to realize of high life-time production. Pregnancy diagnosis is crucial to shortening the calving interval by enabling the farmer to identify open animals so as to treat or re-breed them at the earliest opportunity. MicroRNAs are short RNA molecules which are critically involved in regulating gene expression during both health and disease. This study is sought to establish the feasible of circulating miRNAs as biomarkers of early pregnancy in cattle. We applied Illumina small-RNA sequencing to profile miRNAs in plasma samples collected from 12 non-pregnant cows (“open” cows: samples were collected before insemination (non-pregnant state) and after pregnancy check at the indicated time points) on weeks 0, 4, 8, 12 and 16. Using small RNA sequencing we identified a total of 115 miRNAs that were differentially expressed weeks 16 relative to non-pregnancy (“open” cows). Weeks 8, 12 and 16 of pregnancy commonly showed a distinct increase in circulating levels of miR-221 and miR-320a. Through genome-wide analyses we have successfully profiled plasma miRNA populations associated with pregnancy in cattle. Their application in the field of reproductive biology has opened up opportunities for research communities to look for pregnancy biomarker molecules in dairy cattle.

본 연구의 목적은 분만간격에 따른 추가 착유일수를 계산하여 불완전 Gamma모형으로 추정된 비유곡 선모수값을 통하여 추가 착유일 만큼의 산유량을 계산하고, 추가 착유에 따른 경제성을 분석하기 위함 이다. 경제성 분석을 위하여 농협중앙회 젖소개량사업소에서 진행하고 있는 유우군 능력검정사업에 참 여하고 있는 홀스타인 젖소로부터 조사한 착유기록 2,072개를 분석하였는데, 분석에 이용된 착유기록은 2010년 1월부터 2012년 12월 사이에 분만한 초산우 및 경산우로부터 자료이다. 비유곡선 모수는 Wood 모형을 적용하여, SAS 9.2 NLIN Procedure를 이용해 추정하였다. Wood 모형으로 추정한 비유곡선 함수는 초산우 및 경산우에 대해 각각 yt = 18.00t0.189e-0.00231t 및 yt = 24.73t0.181e-0.00315t로 추정되었다. 초산 우의 경우 산유량이 8,000kg 이하인 우군의 적정 분만간격은 400일 이하로 유지하는 것이 바람직하며, 8,000kg 이상인 우군은 분만간격을 400일에서 500일 사이로 유지하는 것이 바람직하다. 경산우의 경 우 산유량이 9,000kg 우군은 적정 분만간격을 400일 이하로 유지하고, 9,000kg 이상인 우군의 분만간 격은 400일에서 500일 사이로 유지하는 것이 바람직하겠으며, 11,000kg 이상의 고능력 경산우 우군의 경우 분만간격이 길어질수록 순수이익은 증가하나, 차기 임신 및 분만을 위해서는 분만간격을 450일에 서 500일 사이로 유지하는 것이 바람직하다고 할 수 있겠다.

The objective of this research was to evaluate the effects of two different feeding systems on blood metabolites in Holstein heifers and analyze the economic impacts of the feeding systems. The following two experiments were conducted to investigate the effects of feeding system on blood metabolite changes in Holstein heifers and analyze the economic impacts of the two systems. In experiment 1, the effects of two different feeding systems on cortisol, progesterone, and estradiol in Holstein heifers were examined. In experiment 2, the effects of two different feeding systems on the body weights of Holstein heifers and profitability of the two feeding systems were studied. Results showed that the pasture-raised heifers showed significantly decrease in the levels of blood cortisol (p<0.05) and increases in the levels of progesterone and estradiol (p>0.05) when compared with heifers raised in indoor feeding system. The average daily gain was significantly higher (p<0.05) in indoor-raised heifers (0.73 kg/day) as compared to pasture-raised heifers (0.58 kg/day). Also, 25.2% more profits were obtained from the pasture feeding system as compared to the indoor feeding system. These results together would be useful in the investigation of feeding system and growth performance in dairy cattle.

The bean bug, Riptortus pedestris (Hemiptera: Alydidae), is a major pest of soybean and tree fruit in Korea. To protect crops, chemical insecticides have been widely used. However, the effects of insecticides is not only reduce the pest population but also change of pest behavior. In this study, we tested the effects of two insecticides, etofenprox (pyrethroid) and acetamiprid (neonicotinoid), on the behavior of R. pedestris. Two insecticides were diluted with water based on the conventional spray dose. After exposed to insecticide residue, adult R. pedestris was put individually into a clean petri dish with soybean. The behavior of R. pedestris was video-recorded for 16 hours. The frequencies of approaching to food and feeding were compared to the untreated control group. R. pedestris exposed to etofenprox made more frequent approaching to the food, but those exposed to acetamiprid made less frequent approaching compared to the control group. When compared to the control group, the feeding frequency of acetamiprid-exposed group was significantly reduced but etofenprox-exposed group showed more frequent feeding activity. In both treatments, the feeding probability, calculated by feeding frequency divided by approaching frequency, was reduced compared to the control. We conclude that acetamiprid may protect crops by reducing the frequency of R. pedestris to approach and feed on crops.

In order to provide basic data to predict changes of milk components in milk yield, this study was conducted to compare nutritive values of diets collected from organic dairy farms (ODF) and conventional dairy farms (CDF) of Chungnam and Jeonbuk in Korea. The contents of crude fat, crude fiver, neutral detergent fiber, and acid detergent fiber in diets of ODF were significantly (p<0.05) higher compared to those of CDF. The contents of crude protein and crude ash in ODF were also higher (p<0.05) than those of CDF. The contents of calcium, ferrum, and phosphorus in diets of ODF were similar to those of CDF. The contents of potassium, magnesium, and iodine in diets of ODF were higher (p<0.05) than those of CDF. The contents of total saturated and unsaturated fatty acids in diets of ODF were higher (p<0.05) compared to those of CDF. The contents of oleic acid, linoleic acid, and linolenic acid in diets of ODF were higher (p<0.05) compared to those of CDF. However, the contents of myristic acid, palmitic acid, and stearic acid in diets of ODF were lower (p<0.05) compared to those of CDF.

본 연구는 추청벼를 이용하여 총체 벼 사일리지를 조제 하였을 때 총체 벼 사일리지의 사료가치 및 부위별 소화율 을 조사하여 총체 벼의 이용성을 검정하기 위하여 수행되 었다. 총체 벼 사일리지의 무기물 함량은 망간이 가장 높 았으며 탄소, 철, 아연, 구리 등 순으로 나타났다. 그리고 마그네슘 함량이 가장 낮게 나타났다. 추청벼 총체 사일리 지의 아미노산은 glutamic acid 함량이 가장 높았으며 leucine, asparagine, alanine, valine, arginine 순으로 나타났 다. 그리고 methionine 함량이 가장 낮았다. 추청벼 총체 사일리지 부위(총체 벼, 낟알을 제거한 줄기, 왕겨를 포함 한 낟알, 쌀)에 따른 시간별 반추위내 건물 소화율은 쌀이 가장 높았으며 왕겨를 포함한 낟알, 총체 벼, 낟알을 제거 한 줄기 등 순으로 나타났다. 따라서 본 연구에서는 추청 벼 총체 사일리지 소화율은 부위에 따라 약간의 차이를 보 였으며 무기물 중 망간 그리고 아미노산 중 glutamic acid 가 가장 높은 함량을 보였다.

This study was conducted to investigate the effects of the slaughtering age on carcass characteristics and economic efficiency of Holstein steers. The Holstein steers (n=27, 4 months old, average body weight 160 ㎏) were divided into 3 groups and raised with TMR feeding formulation until 18, 20 and 22 months old, respectively. In the result, final body weights were 703, 768 and 804 ㎏, and average daily gains were 1.32, 1.32 and 1.27 ㎏, respectively. Dry matter intakes (DMI) were 8.62, 8.94 and 9.24 ㎏. Feed conversion ratio was 6.53, 6.77 and 7.28 for 18, 20 and 22 months old groups. Feed conversion ratio was increased as the fattening periods increased. In yield traits, carcass weight was significantly lower in 18 months old group compared to other groups (p<0.05). The back fat thickness were 8.4, 7.3 and 7.8 ㎜, rib eye area were 70.6, 73.4 and 73.84 ㎠, and the meat yield index was 62.9, 62.5 and 62.1 when slaughtered at 18, 20 and 22 months old, respectively. In the frequency of the yield grade (A:B:C, %), grade B was highest at 20 months old group as 0:75:25. In the quality traits, marbling score, texture and maturity were not different among slaughtering age groups. However, marbling score tended to be increased at 22 months old group. Meat color and fat color were higher at 22 months old group compare to other groups (p<0.05). In the frequency of the quality grade (1+:1:2:3,%), 22 months-old group was the greatest as 12:0:50:38. The income was highest for 20 months old group as 279 thousand wons among the 3 groups. Therefore, the slaughtering ages of Holstein steers may be appropriate at 20 months old.

This study was conducted to investigate the effects on in situ ruminal degradation of feed protein sources (soybean meal, P-SBM; dried distillers grain with solubles, P- DDGS; wheat bran, P-WB) treated with protease as compared with conventional feed protein sources (soybean meal, SBM; dried distillers grain with solubles, DDGS; wheat bran, WB). There was no significant change in the chemical composition and amino acid profiles of enzyme treatment protein sources compared with the non-treated groups (p<0.05). But for treatment groups, the solid content and total amino acids were reduced by increasing the moisture content due to proteolytic conditions. On the entire incubation time in situ ruminal degradation rate of dry matter appeared higher in treatment groups compared to control groups (p<0.05), and that of the treatment groups suspended during 48 hours were in the order of P-SBM (97.70%), P-WB (74.26%) and P- DDGS (72.39%). In particular, DM degradation rate of enzyme treated DDGS significantly increased to 43.62%, 45.99%, 55.97%, 69.87% and 72.39%, respectively, incubated during 3, 6, 12, 24 and 48 hours in rumen (p<0.05). Also protein degradation rate of P-WB and P-SBM significantly decreased compared to their respective non-treated sources; however, by contrast, in DDGS it was increased. For P-SBM, protein degradation rate significantly decreased at 6 and 12 hours, and for P-DDGS it was increased at 3 and 6 hours of suspension times in rumen (p<0.05). In particular, protein degradation rate of enzyme treated group suspended for 48 hours were in the order of P-SBM (91.81%), P-WB (86.36%) and P-DDGS (58.87%). This result suggests that protease treatment of feed protein sources might be utilized to increase the bypass ratio into post-rumen for wheat bran, soybean meal, and to improve the utilization of feed protein.

This study was carried out to elucidate changes in milk production, milk components and milk product properties as influenced by organic and conventional farming system. Milk production in transient organic feeding was lower by 7.6% than that in conventional feeding and also milk fat, milk protein content, solids not fat and somatic cell count were lower than conventional farming system. But, milk lactose content in transient organic feeding was higher than that in conventional feeding. Ca and Fe content in milk in organic feeding tended to be higher compared to conventional feeding. Linoleic acid and unsaturated fatty acids in milk in organic feeding was higher than those in conventional feeding and properties of milk products were improved in organic milk compared to conventional milk.

This study was conducted to evaluate effects of chopped and non-chopped rice straw on characteristics of silage-basedtotal mixed ration (TMR) according to the particle size, laceration, and in situ dry matter (DM) degradation. The threerice straw silages as low moisture unchopped (LMUC; 32.75% of moisture, unchopped), high moisture unchopped(HMUC; 42.05% of moisture, unchopped), and high moisture chopped (HMC; 44.71% of moisture, chopped to 30cmlengths) were tested. Samples were collected at every 5 minutes from 10 min of pre-mixing to 50 min. The percentageof >19mm in LMUC and HMC was decreased to 7.23% and 7.74% (p<0.05), respectively, and the percentage of 8mm>was increased to 5.81% and 5.24%, respectively. Furthermore, the laceration of forage by a TMR mixer showed that therewas little change in the reduction of 1.26% in HMC, but was reduced to 7.53% and 16.06% in LMUC and HMUC,respectively. The peNDF>8 was maintained 17~18.5% of the optimal requirement level for 15 to 45 min mixing in LMUCand for 30 to 50 min mixing in HMC, but it exceeded the level of peNDF>8 in the range of 21.49 to 22.53% for 50minmixing in HMUC. However, ruminal in situ DM degradation appeared as LMUC>HMUC>HMC. Therefore, theseresults suggest that the rice straw silage may be useful for high-yielding lactating cows, if it can be supplied with theadequate peNDF, and the limiting factor on DMI and DM degradation was reduced by crushing of the plant tissue, althoughthe rice straw silage was concerned to low quality forage.

This study was carried out to investigate the effect of DDGS hydrolysate (H-DDGS) and rumen-protected lysine-choline complex (RPLC) on milk production and blood metabolites in dairy cows. Feeding trials was performed to latin-square design using the 4 mid-lactational cows for 8 weeks, and treated with T1 (H-DDGS 1.1 kg), T2 (H-DDGS 0.73 kg + RPLC 0.15 kg), T3 (H-DDGS 0.37 kg + RPLC 0.30 kg) and T4 (H-DDGS 0.37 kg + RPLC 0.15 kg) according to the content of protein source. Dry matter intake (DMI) of TMR and average weight showed no significant difference between treatments. The milk production of T1, T2 and T4 were significantly higher than T3 treatment (p < 0.05), and milk/DMI efficiency tend to increase in the T1. Milk components showed no significant difference between treatments, however, the milk protein of T2 increased to 0.15% than T1. Also blood metabolites showed no significant difference between treatments. But T-CHO level numerically represented a lower trend in the treatments of adding to RPLC compared with T1. This result suggests that the high level (1.1 kg) of H-DDGS is expected to improve the feed utilization without the negative impact on weight gain, feed intake and milk production as the lactation stage of dairy cows proceeds, and 0.15 kg of RPLC under the same feeding conditions of H-DDGS may be useful on fat metabolism.

Recently, detection of esophageal diverticula by neck ultrasonography has been increasing. In particular, esophageal diverticula near the thyroid gland can be diagnosed as thyroid nodule on ultrasonography. To date, 13 cases of ultrasonographic features of Killian-Jamieson (K-J) diverticula have been reported. We report on four cases of K-J diverticula and discuss clinical characteristics, including ultrasonographic findings, in comparison with previously reported cases. Awareness of ultrasonographic finding of esophageal diverticula, a hypoechoic nodule containing echogenic foci found in the posterolateral aspect of the thyroid, is most important for making a differential diagnosis of K-J diverticulum from a thyroid nodule.

The study was performed to evaluate the effects of soybean meal (T1) and corn distillers dried grains with solubles (DDGS, T2) hydrolyzed by microbial proteolytic enzyme of Protame® on milk production and protein contents in dairy cows. Total of nine Holstein cows (i.e., 1.67 ± 0.47 average parity and 23.7 ± 1.2 kg/d average milk yield) were randomly assigned to control, T1, and T2 (e.g., 3 animals per group) and treated for 4 weeks. Milk yield of 3 different groups was similar in the beginning of the study, however the milk yield of T1 and T2 treatment group had increased by 0.93 kg/d and 1.89 kg/d, respectively. Milk protein level of T2 treatment group was increased by 0.19% (e.g., 0.14 kg/d protein content), whereas there was no significant different in control and T1 group. In conclusion, blood metabolites were ranged in normal level, but BUN content was reduced from 19.03 mg/dl to 17.70 mg/dl in T2 treatment group. This result suggests that DDGS hydrolysate supplement efficiently increase milk yield and milk protein level as well as feed protein availability in dairy cattle.

This experiment was conducted to determine the effect of increasing the dietary levels of nattokinase (NK) addi-tives on milk production and composition, and blood metabolites in dairy cows. NK additives with high fibrinolytic activity were produced by the strain with similarity to the Bacillus amyloliquefacines. A total 20 mid-lactating Holstein cows (average body weight 652.00 ± 4.38 kg; average 2.25 ± 0.35 parity; average milk yield 24.4 ± 0.38 kg/d) were randomly assigned to three treatments (5 animals per treatment). Cows were fed TMR supplemented with DDGS 100 g for control, NK additives 100 g and 200 g for T1 and T2 treatment, respectively for 4 weeks. By the increases of NK additives, milk yield increased for T1 (1.35 kg/d) and T2 (0.98 kg/d) at the final period than at the initial period (p < 0.05). But milk protein content decreased for T1 (3.20%) and T2 (3.24%) than for control (3.56%) (p < 0.05). Blood triglyceride, T-CHO and BUN levels in T1 decreased compared with that in control and T2 (p < 0.05). This finding showed that 100g of NK additives could possibly have a positive effect in lactation performance of mid-lactation Holstein cows by increasing milk yield, improving protein metabolism and decreasing cholesterol in blood.