• Journal of the korean veterinary medical association
• /
• v.13 no.2
• /
• pp.129-134
• /
• 1977

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.42 no.1
• /
• pp.17-25
• /
• 2022

This study was carried out the estimation on consumption patterns and consciousness of domestic forage for improvement of the quality of domestic forage. Although the cultivated area in South Korea of forage has increased significantly compared to the past, the self-sufficiency rate of domestic forage has increased to around 80% since 2010. Also, livestock farmers prefer to use import forage than domestic due to convenience of use. In Korean beef farms, the ratio of import to domestic forage was higher in domestic forage (import forage 3 : domestic forage 7). In the method of securing domestic forage, purchase of forage (55.6%) was higher than self-cultivation of forage (44.4%). The ratio of use by bailing type was shown in the order of rice staw rice straw (50.5%), domestic hay (15%), imported hay (12.5%), and total mixed ratio (10.7%). The preference of forage was in the order of amount of foreign matter, moisture content, price, feed value in Korean native cattle farm. The result of satisfaction with domestic and import forage showed that the satisfaction of domestic forage price was higher than import forage, while the moisture content and foreign matter of forage were lower than import forage. In addition, in the results of the satisfaction and importance of domestic roughage compared to imported roughage, satisfaction with imported roughage was generally high in all items except for price. As a result, in order to improve the satisfaction of domestic forage in Korean native cattle farm, it is necessary to minimize foreign matter in forage and increase hay production for moisture content uniform in forage.

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.11
• /
• pp.1691-1699
• /
• 2018

Objective: In Korea, there are three main cattle breeds, which are distinguished by coat color: Brown Hanwoo (BH), Brindle Hanwoo (BRH), and Jeju Black (JB). In this study, we sought to compare the genetic diversity and divergence among there Korean cattle breeds using a BovineHD chip genotyping array. Methods: Sample data were collected from 168 cattle in three populations of BH (48 cattle), BRH (96 cattle), and JB (24 cattle). The single-nucleotide polymorphism (SNP) genotyping was performed using the Illumina BovineHD SNP 777K Bead chip. Results: Heterozygosity, used as a measure of within-breed genetic diversity, was higher in BH (0.293) and BRH (0.296) than in JB (0.266). Linkage disequilibrium decay was more rapid in BH and BRH than in JB, reaching an average $r^2$ value of 0.2 before 26 kb in BH and BRH, whereas the corresponding value was reached before 32 kb in JB. Intra-population, interpopulation, and Fst analyses were used to identify candidate signatures of positive selection in the genome of a domestic Korean cattle population and 48, 11, and 11 loci were detected in the genomic region of the BRH breed, respectively. A Neighbor-Joining phylogenetic tree showed two main groups: a group comprising BH and BRH on one side and a group containing JB on the other. The runs of homozygosity analysis between Korean breeds indicated that the BRH and JB breeds have high inbreeding within breeds compared with BH. An analysis of differentiation based on a high-density SNP chip showed differences between Korean cattle breeds and the closeness of breeds corresponding to the geographic regions where they are evolving. Conclusion: Our results indicate that although the Korean cattle breeds have common features, they also show reliable breed diversity.

• Asian-Australasian Journal of Animal Sciences
• /
• v.10 no.4
• /
• pp.416-421
• /
• 1997

The effect of imported young bulls on the genetic progress was examined in the Holstein dairy cattle population in Japan. The effect of the difference of mean genetic merit between imported and domestic young bulls ("genetic difference") was recognized on the genetic progress of the domestic animals in the early stage of selection. On the other hand, the genetic progress of domestic animals were remarkably influenced by the genetic trend of imported young bulls ("genetic trend") in the later stage. Import of young bulls originated from high genetic level of young bulls originated from high genetic level population improved the genetic progress of domestic population. But, the increase of the immigration ratio of imported young bulls ("immigration ratio") did not influence linearly on the progress of the genetic merit of domestic animals. Even if "immigration ratio" was 100%, the genetic merit of domestic animals could not overcome the one of imported young bulls. In the later stage of selection, the genetic merit of domestic animals ran parallel to those of imported young bulls.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.9
• /
• pp.1368-1372
• /
• 2014

Several studies arduously reported that gayal (Bos frontalis) is an independent bovine species. The population size is shrinking across its distribution. In Bangladesh, it is the only wild relative of domestic cattle and also a less cared animal. Their body size is much bigger than Bangladeshi native cattle and has prominent beef type characters along with the ability to adjust in any adverse environmental conditions. Human interactions and manipulation of biodiversity is affecting the habitats of gayals in recent decades. Besides, the only artificial reproduction center for gayals, Bangladesh Livestock Research Institute (BLRI), has few animals and could not carry out its long term conservation scheme due to a lack of an objective based scientific mission as well as financial support. This indicates that the current population is much more susceptible to stochastic events which might be natural catastrophes, environmental changes or mutations. Further reduction of the population size will sharply reduce genetic diversity. In our recent investigation with 80K indicine single nucleotide polymorphism chip, the $F_{IS}$ (within-population inbreeding) value was reported as $0.061{\pm}0.229$ and the observed ($0.153{\pm}0.139$) and expected ($0.148{\pm}0.143$) heterozygosities indicated a highly inbred and less diverse gayal population in Bangladesh. Prompt action is needed to tape the genetic information of this semi-domesticated bovine species with considerable sample size and try to investigate its potentials together with native zebu cattle for understanding the large phenotypic variations, improvement and conservation of this valuable creature.

• Korean Journal of Veterinary Research
• /
• v.39 no.3
• /
• pp.478-488
• /
• 1999

The contents of histidine dipeptides, a metabolic products of muscle protein, were investigated to compare muscle composition among the 9 domestic animals including cattle. In major domestic animals, analyzed the effects of age, part and sex of the animals on their muscle composition. Large amounts of carnosine($68.63{\pm}17.41{\mu}mol/g$) were detected in cattle and it was higher than other animals. Whereas the content of anserine showed high level in order of turkey, chickens and duck. The ratio of carnosine and anserine(C/A ratio) was different depending on the animal species. Statistical data indicated that difference among species was significant(p < 0.05). The contents of histidine dipeptides in heated muscle by boiling for 40 minutes at $110^{\circ}C$ was similar to thoes of raw muscle. C/A ratio in heated muscle was not different from that of raw muscle, indicating that no change has been made after heating process. The contents of carnosine and anserine were different according to the parts of their muscle. Especially chuck of the mammalian showed extremely low level of histidine dipeptides compared with other parts, while C/A ratio maintained certain level regardless of age, part, sex. Therefore, based on the content of histidine dipeptides, could be found the difference of muscle composition among the species. Also C/A ratio of horse, pig, cattle, duck, sheep and turkey were characteristic respectively.

• Korean Journal of Veterinary Service
• /
• v.38 no.4
• /
• pp.221-225
• /
• 2015

The bacterium causing Johne's disease (JD), Mycobacterium avium subspecies paratuberculosis (MAP), is distributed worldwide and causes progressive intestinal disease, also known as paratuberculosis, in domestic and exotic ruminants, including cattle. The subclinical form of this disease results in progressive weight loss, reduced milk production, lower slaughter value, and premature culling, with possible impacts on fertility and udder health. Eventually, infection can lead to the clinical form that manifests chronic diarrhea, emaciation, debilitation, and eventual death. JD is a major cause of economic loss in cattle industry. In this study, serological testing was conducted by ELISA to determine the prevalence of MAP in Korean native cattle of Jeju during the duration of 2010 to 2013. A total of 5,150 blood sera were collected in 111 farms and the samples were classified into four different age groups for MAP; group 1 (2 years or less), group 2 (2~4 years), group 3 (5~7 years), and group 4 (over 8 years). Overall seroprevalence of MAP was 5.2% (269/5,150), and annually from 2010 to 2013, they were 11.6% (106/915), 2.1% (10/474), 5.5% (89/1,627), and 3.0% (64/2,134), respectively. Also, the prevalence rates was determined by age groups: 48 of group 1 (17.8%), 154 of group 2 (57.3%), 48 of group 3 (17.8%), and 19 of group 4 (7.1%) were seropositive for MAP. Although seropositive samples were found in all age groups, the highest seroprevalence was found in group 2. This study showed that during the investigation the seroprevalence of MAP tended to decrease.

• Journal of Environmental Health Sciences
• /
• v.38 no.2
• /
• pp.142-150
• /
• 2012

Objectives: To estimate the multi-antibiotic resistant bacterial contaminant load discharged from livestock farms, we randomly selected livestock farms specializing in cattle, swine, and fowl and collected bacterial strains from domesticated animal feces and compost samples. Problems with resistance to antibiotics are becoming worldwide issues, and as the consumption of antibiotics appears to be excessive in Korea as well, the emergence of antibiotic resistant bacteria shows the possibility to cause potentially serious social problems. Methods: To monitor multi-antibiotic resistant bacterial constituents, aerobic bacteria and Escherichia coli were isolated from domesticated animal feces and compost. Antibiotic resistance testing was performed by the disc diffusion method using 13 different antibiotics. Results: Examining the degree of sensitivity to antibiotics of the aerobic bacteria originating from domesticated animal feces, fowl feces showed the highest distribution rate (35.5%), followed by swine feces compost (23.1%), swine feces (18.2%), cattle feces (14.9%), and cattle feces compost (8.2%). Antibiotic resistance tests of aerobic bacteria and E. coli originating from domestic animals feces resulted in 83.6% and 73.5% of each strain showing resistance to more than one antibiotic, respectively. Conclusions: These results suggest that increasing multi-antibiotic resistant bacteria in the environment has a close relation to the reckless use of antibiotics in livestock.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.3
• /
• pp.440-447
• /
• 2009

Domestic ruminant animals are reared in diverse production systems, ranging from extensive systems under semi-arid and tropical conditions with poor feed resources to intensive systems in temperate and cold areas with high quality feed. Nitrogen (N) recycling between the body and gut of ruminants plays a key role in the adaptation to such diverse nutritional conditions. Ammonia and microbial protein produced in the gut and urea synthesized in the liver are major players in N-recycling transactions. In this review, we focus on the physiological factors affecting urea production and recycling. Sheep and buffalo probably have higher abilities to reabsorb urea from the kidney compared with cattle. This affects the degree of urea-N recycling between the body and gut at both low and high N intakes. The synthesis and gut entry of urea also differs between cattle bred for either dairy or beef production. Lactating dairy cows show a higher gut entry of urea compared with growing cattle. The synthesis and recycling of urea dramatically increases after weaning, so that the functional development of the rumen exerts an essential role in N transactions. Furthermore, high ambient temperature increases urea production but reduces urea gut entry. An increase in total urea flux, caused by the return to the ornithine cycle from the gut entry, is considered to serve as a labile N pool in the whole body to permit metabolic plasticity under a variety of physiological, environmental and nutritional conditions.

• Korean Journal of Veterinary Research
• /
• v.38 no.3
• /
• pp.595-599
• /
• 1998

The present study was undertaken to develop the kit for indirect immunofluorescence antibody test(IFAT) and to investigate the prevalence of N caninum in cattle and dogs in Korea. The neo-antigen kit of IFAT developed in our laboratory was proved diagnostic efficacy by compared with the kit of veterinary medical research and development(VMRD). A survey of N caninum infections among cow and dogs in elevn areas of southern part of country was performed using a IFAT. The infection rate of 190 nationwide cattle was 8.4%(16/190) but was 75%(45/60) at P area in Chunnam province where the cattle showed the abortion repeatedly. Any of the dogs was not N caninum -positive in the Kangwon and Kyonggi areas.