• Journal of Embryo Transfer
• /
• v.33 no.2
• /
• pp.55-59
• /
• 2018

Ensuring timely ovulation concerning the service is valuable. A satisfactory conception rate can be achieved by making sure that ovulation occurs within 7-18 hours after artificial insemination (AI). Delayed ovulation is one of the disturbances commonly encountered in repeat breeding animals. Although demanding research, many studies have not been conducted. Therefore, we aimed to examine the relation between ovulation confirmation and conception rate in dairy cattle. The research findings showed that the signs of true estrus were bred 12 hours after the onset of estrus by AI in cattle. Also, the performance of AI on ovulation was confirmed by the presence of fluctuant Graafian follicles through rectal palpation. From the results, we confirmed that cow encountered delayed ovulation were bred again. The Conception rate in cows with confirmed ovulation was 51.9%, while for those without confirmed ovulation were 33.3%. In conclusion, the results indicate that ovulation confirmation will likely increase conception rate.

• Journal of Biosystems Engineering
• /
• v.19 no.4
• /
• pp.329-342
• /
• 1994

In order to reduce the production cost and improve the quality of dairy feed, several dairy feed mill models suitable for Korean farm size were developed. 6 TMR models were developed for the 1000, 600, 200 head of dairy cattle, and evaluated for capital investments and production costs to suggest the best model. Followings are summary of this study : 1. TMR terminal models were designed that dairy production capacity of TMR1000 models are 40 ton/day, TMR600 model is 20 ton/day and TMR200 models are 10 ton/day. Also, they can be extended their capacity up to twice. 2. Capital investment of TMR terminal models is 145 million won for TMR200-1,205 million won for TMR600 and 609 million won for TMR1000-3 model. 3. The bigger TMR terminal model has the more advantage in production cost. The best model for 1000 head of dairy cattle farm was TMR1000-3 with 10,849 won/ton of production cost, TMR600 for 600 head of dairy cattle farm with 13,829 won/ton, TMR200-1 for 200 head of dairy cattle farm with 16,943 won/ton of production cost, so feed production cost for the 200 head farm was 50% higher than 1,000 head size farm.

• Journal of Animal Science and Technology
• /
• v.57 no.4
• /
• pp.13.1-13.5
• /
• 2015

As an alternative to radioimmunoassay a simple and highly sensitive enzyme immunoassay (EIA) was developed and validated for androstenedione quantification in plasma of Karan Fries bulls using second antibody coating technique. The wells of the microtitreplate were coated with affinity-purified goat immunoglobulin (antirabbit IgG) that binds the hormone specific antibody. The EIA was performed to analyze androstenedione directly in $40{\mu}l$ of bull plasma. The androstenedione standards ranged from 0.20 to 200 pg/$40{\mu}l$/well and the sensitivity of the assay was 5 pg/ml plasma. Serially diluted bull plasma containing high endogenous androstenedione showed good parallelism with bovine androstenedione standard curve. Intra- and inter-assay coefficients of variation (CV) were found to be 8 and 9%, respectively. Peripheral plasma androstenedione concentrations determined in young and adult bull samples ranged between 104-990 pg/ml and 184-2040 pg/ml, respectively.

• Korean Journal of Veterinary Research
• /
• v.34 no.1
• /
• pp.93-97
• /
• 1994

A immunological survey of paratuberculosis in dairy and Korean native cattles was conducted by enzyme linked immunosorbent assay(ELISA), complement fixation test(CFT), agar gel immunodiffusion test (AGID) and intradermal skin test(ID). Over all prevalence of pararuberculosis in cattles was 6.7%(109/1633) by ID, 7.5(205/2719) by AGID, 9.3% (245/2641) by CFT and 13.4%(363/2719) by ELISA. Prevalence in dairy cattle was higher than that of Korean native cattle. Of 70 ELISA-positive cattle, 23(28.6%) and 48(68.6%) cattles were classified as positive in the AGID and positive or suspect in CFT, respectively. Of 92 ELISA-suspect cattle, 32(34.9%) and 48(52.2%) cattles were classified as AGID-positive and CFT-positive or suspect, respectively. It was concluded that paratuberculosis is widespread in cattle of Korea.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.9
• /
• pp.1262-1268
• /
• 2012

The present investigation was designed to determine whether supplementation of different level of vitamin E for 12 months to arsenic exposed goats (50 ppm as sodium arsenite) affords protection against the blood hemato-biochemical parameters caused by the metalloid. A total of 24 crossbred (Alpine${\times}$Beetal) lactating goats were assigned randomly into 4 equal groups (control, $T_1$, $T_2$ and $T_3$) of 6 in each, on the basis of average body weight ($36.10{\pm}0.11$ kg) and milk yield ($1.61{\pm}0.04$ kg/d). The animals in $T_1$, $T_2$ and $T_3$ were given 50 ppm arsenic, while in $T_2$ and $T_3$, additionally; vitamin E at the rate of 100 IU and 150 IU/kg dry matter (DM) respectively was additionally supplemented for the period of 12 months. Hemoglobin (Hb), total leukocyte (TLC) and blood lymphocyte % were decreased (p<0.05) in arsenic fed groups and vitamin E supplementation in the experimental group showed a protective potential. Significant increases (p<0.05) in aspertate transaminase (AST) and alanine transaminase (ALT) activities among arsenic supplemented groups were recorded, however vitamin E supplementation at higher doses showed a protective effect (p<0.05) against AST but in the case of ALT no ameliorating effect was found in either of the doses. Plasma total protein was decreased (p>0.05) but creatinine level was periodically increased in all As supplemented groups and vitamin E supplementation did not produce any protective effect. It can be concluded that arsenic exposure resulted in varying degree of changes in hemato-biochemical parameters and activities of antioxidant enzymes in goats but concomitant treatment with Vitamin E is partially helpful in reducing the burden of arsenic induced effect.

• Korean Journal of Veterinary Research
• /
• v.48 no.2
• /
• pp.191-195
• /
• 2008

This study was performed to detect Neospora caninum in blood of 61 Korean native cattle and 50 dairy cows in Chungnam province. All of them were healthy and did not show any clinical signs. DNA was isolated from blood samples and a 328 bp fragment was amplified by PCR using primer pair Np21 and Np6. The PCR positive rate was 14.8% in Korean native cattle and 0% in dairy cows. Cows with 15.6% were a little higher than bulls with 12.5% in gender. The detection rate of over 3-year-old Korean native cattle was 28.6% in age. The results demonstrate that N. caninum DNA can be detected in blood by PCR. PCR analysis in blood may be useful to annually screening test for N. caninum infection in clinically healthy cattle.

• KCID journal
• /
• v.18 no.1
• /
• pp.18-24
• /
• 2011

The suitable area of forage crop field was calculated under the assumption that all of the liquied manure would be used to nutrient of crops at the Saemangeum crop-livestock complex. At first, Korean cattle and dairy cattle were selected and swine was excluded becausr of high pollution availability. When forage crop was calculated from nutrient amounts of manure of livestocks and standard applicable fertilizer quantity to the selected forage crops, 232ha (278ha including infrastructure part) was determined to be appropriate in case of 2500 heads of Korean cattle and 300 heads of dairy cattle were raised. From the result by that calculated ares (232ha) to forage crop feeding could be possible to the Korean cattle and dairy cattle feeding using TDN index, more than 217ha of forage crop fields would be satisfied nutritionally.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.33 no.3
• /
• pp.193-196
• /
• 2013

This study was carried out to evaluate the physical characteristics of total mixed rations (TMR) prepared in Korea for improving productive effectiveness of dairy and beef cattle. The 40 samples of commercial TMR for dairy and beef cattle in 6 municipals were collected and analyzed for chemical composition and physical properties. There were significant regional differences (p<0.05) in dry matter and crude protein contents of TMR for dairy and beef cattle. In roughage value index (RVI), neutral detergent fiber (NDF) content, and physically effective NDF (peNDF)$_{1.18}$ content, there were no regional differences in TMR for dairy cattle, but there were significant regional differences (p<0.05) in TMR for beef cattle. Thus the results from this study support that because RVI, NDF content, and peNDF content in TMR for dairy and beef cattle exceeded recommended ranges, a little adjustment in TMR for dairy cattle will be necessary to obtain optimal productivity.

• Korean Journal of Veterinary Service
• /
• v.35 no.4
• /
• pp.333-337
• /
• 2012

This study was carried out to investigate the prevalence of bovine leukemia virus (BLV) infection and to compare the results of enzyme-linked immunosorbent assay (ELISA) and nested polymerase chain reaction (nPCR) in dairy farms in northern Gyeonggi province from August through December 2011. A total of 625 dairy cattle from 14 dairy farms were tested for antibodies against BLV using commercially available ELISA test kit. The overall seroprevalence of BLV infection was 76.3%. The seroprevalence of diary cattle according to age was the highest at 61~72 months (88.0%, P<0.001). Two hundred fifty one dairy cattle from 7 diary farms were tested ELISA and nPCR. The kappa value of BLV between ELISA and nPCR was 0.765. The results indicate that BLV infection spread widely in dairy farms and the nPCR is rapid method for the early detection of BLV infection.

• Journal of Dairy Science and Biotechnology
• /
• v.35 no.3
• /
• pp.162-168
• /
• 2017

Mastitis is a common and serious infection of the mammary gland in dairy cattle and has a major economic impact on the production of milk and dairy products. Bacterial mastitis is caused by several pathogens and is most frequently associated with coagulase-negative staphylococci (CNS). Although CNS are typically associated with subclinical or mild mastitis, the importance of CNS has increased as these pathogens have emerged as predominant mastitis-related pathogens in many countries. CNS can cause persistent infections, resulting in increased milk somatic cell counts and thereby affecting milk quality and decreasing milk production. Globally, Staphylococcus chromogenes, S. epidermidis, and S. simulans are the predominant CNS species in dairy cattle mastitis. Antibacterial resistance of CNS varies with species, and most CNS are susceptible to vancomycin and resistant to penicillin and tetracycline. As the most frequently isolated CNS species, some strains of S. chromogenes exhibit phenotypic resistance to ampicillin, erythromycin, oxacillin, penicillin, and tetracycline. Some strains of S. epidermidis and S. haemolyticus are only susceptible to vancomycin and rifampicin. Therefore, more studies are needed to achieve the control and prevention of CNS as environmental pathogens.