• Korean Journal of Veterinary Service
• /
• v.46 no.4
• /
• pp.283-291
• /
• 2023

Brucellosis and tuberculosis are major infectious and contagious bacterial diseases in cattle. These diseases are malicious diseases that must be inspected at the slaughterhouse of cattle in accordance with the practice of quarantine in Korea. Furthermore, both diseases lead to abortion, reproductive disorder, and calf disease, causing major difficulty in the breeding of Korean Native cattle (Hanwoo), a representative industrial animal currently being raised in Korea. Co-infections of these diseases intensify clinical symptoms such as abortion and have a particularly significant effect on increasing mortality. Thus, serological tests were performed in Hanwoo, to establish the association of co-infection between brucellosis and tuberculosis in cattle. ELISA and PCR tests were conducted on blood samples collected from a total of 102 cattle in Jeonnam province, Korea, to detect brucellosis and tuberculosis infections. The PCR results revealed that 41 samples tested positive for Brucella abortus (B. abortus) infection (40.20%), and 5 samples tested positive for Mycobacterium bovis (M. bovis) (4.90%) infection confirmed by PCR. Notably, 9.76% (4/41) of the cattle infected with brucellosis also tested positive for tuberculosis. In conclusion, this study highlights the co-infection of brucellosis and tuberculosis among Hanwoo cattle in Jeonnam province, which is expected to contribute to our understanding of disease transmission, pathogenicity, the establishment of future prevention strategies.

• Journal of Animal Science and Technology
• /
• v.59 no.3
• /
• pp.5.1-5.10
• /
• 2017

Background: Bovine respiratory disease (BRD) is one of the leading causes of economic losses in the beef and dairy industry. Reliable antemortem tools for diagnosing BRD would improve the efficacy of treatment and reduce costs. Here we examined whether the relatively simple technique of thoracoscopy can support BRD diagnosis under field conditions. We also compared various equipment set-ups in order to optimize the safety and efficacy of the procedure. A total of 24 thoracoscopic procedures were performed in 17 calves diagnosed with BRD and in 2 healthy control calves. Rigid and flexible endoscopes and industrial videoscopes were tested using various insertion approaches. The suitability of the technique was assessed in terms of duration, volume of air extracted, visualization score, and image quality. Safety was assessed in terms of rectal temperature, body weight, breaths/min, presence of fibrinogen, pain score, recovery time, intraoperative complications and risk of laceration or threatening collapse. Results: Insertion of a flexible endoscope via a right, dorso-caudal approach at the $5^{th}$ intercostal space allowed complete examination of the right lung in 15 min, as well as identification of main lung lesions and adherences in calves with BRD, without compromising calf welfare. While the dorso-caudal approach was optimal, it was associated with substantial discomfort when rigid endoscopes were used, minimal complications or mortality due to thoracoscopy were observed up to 28 days after the procedure. Videoscopes were as safe and easy to use as endoscopes, but endoscopes provided better image quality. Conclusion: This study provides the first field evidence that thoracoscopy can be safe to explore BRD-diseased calves. These results justify a larger study to rigorously assess the diagnostic performance of the technique.

• Journal of Veterinary Clinics
• /
• v.17 no.1
• /
• pp.93-101
• /
• 2000

This study was carried out to investigate the epidemiological prevalence of diseases from birth to weaning in 268 Koeran native calves which was delivered from three stock farm in Chonbuk area. We examined body weight gain, incidence rate of diseases and mortality rate in relation to age, season, environmental temperature and rearing management conditions for one year. The results of this experiment were as follows: Birth weight and body weight gain of Korean native calves born of primiparae were lower than those of multiparae. Body weight gain of diseased calves was lower than normal calves. Of 268 delivered calves, 242 calves(90.3%) were affected with gastronistestinal and/or respiratory diseases. The prevalence of the diseases were gastronitestinal disease(54.1%), gastronitestinal and respiratory disease(21.6%), and respiratory disease(14.5%). Of 242 diseased calves, 33 calves(13.6%) were occurred gastronitestinal disease and respiratory disease at different time respectively. Of 268 delivered calves, 126 calves were died(47%). The prevalence of the death were gastronitestinal disease(31.4%), gastronitestinal and respiratory disease(14.5%), and respiratory disease(1.1%). 81% of the diseases and 76.2% of the death were occurred in winter and a change of season(December to May). 59.1% of the diseases and 52.4% of the death were occurred at atmospheric temperatures below 1$0^{\circ}C$. 91.7% of the diseased calves and 96.8% of the dead calves were born of primiparae. 77.2% of the gastronitestinal disease were occurred within 2 weeks old, and the incidence was decreased with increasing age. Whereas the incidence of respiratory disease was incidence with ageing, and 69.2% of the respiratory disease were occurred between 2 weeks and 5 weeks old. And 62% of the gastronitestinal and respiratory disease wre occurred between 1 week and 3 weeks old. 65.1% of the dead calves were died within 2 weeks old. The morbidity and population mortality rate in each farm stock were 56.5%-104.9%, and 14.5%-64.2%, respectively.

• Journal of Embryo Transfer
• /
• v.19 no.2
• /
• pp.133-145
• /
• 2004

Serum-contain is commoly used for the production of in vitro-derived bovine embryos. However, were biological activity of serum varies from lot to lot, time consuming to choose better serum with good quality and risks of virus, bacteria and mycoplasma infection. This study established serum-free culture systems of in vitro embryo development to efficiently obtain a large number of blastocysts from ovaries of Hanwoo and oocytes maturation, cell number, tlerance of cryopreservation. Secondly, serum-contain medium is suspected of contributing to the large calf size, dystocia, cersarean sections, calf mortality and confirmed these blastocysts are high quality in terms of cyotolerance, high rates of pregancy and normal birth. For these reasons, Culture media (IVMD101 and IVD101) designed specifically for the preimplantation bovine embryo are rather simplistic, being based on salt solutions with additional energy substrates and growth factors. An improved serum-free medium (IVMD101) was developed for bovine oocytes maturation in vitro. Proportions of embryos developing to the blastocyst stage cultured in both IVD101(32.4%) and IVD101(34.5%) serum-free media were higher than in TCM199+10% FBS(12.4%) serumcontaining medium. Futhermore, the cell numbers per blastosyst obtained in the serum-free media were superior to those of blastocysts developed in serum-supplemented medium. Also, cell numbers of blastocysts obtained in the serum-free media were similar with blastocysts derived in vivo. Survival rate blastocysts after 24 hr incubation after thawing, the blastocysts cultured in both IVD101(94.5%) and IVD101(95.8%) serum-free media were higher than in TCM199+10% FBS (52.5%) serum-containing medium. After 72 hr incubation after thawing, hatching rates of blastocysts developed in IVD101(78.4%) and IVMD101(83.7%) were sighnificantly higher than that developed in the serum-supplemented medium(32.0%). The pregnancy rates almost not different between fresh blastocysts(38.2%) and frozen blastocysts(34.9%). The results suggested that the improved serum-free media(IVMD101 and IVD101) offer several advantages over culture in serum-cotaining medium, including increased rates of blastocyst formation and high cel numbers. Additionally, the survival and hatching rates of embryos product in serum-free media after post-thaw culture were superior to those of embryos produced in the serum-containg medium and useful for the production of high quality bovine embryos for cryo-preservation. These improved serum-free media are beneficial not only for the study of the mechanisms of early embryogenesis but also for mass production of good quality embryos for embryo transfer, cloning and transgenesis.