• Animal Bioscience
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• v.34 no.5
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• pp.811-823
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• 2021

Objective: Eggshell color is an important indicator of egg quality for consumers, especially for brown eggs. Various factors related to laying hens and their environment affect brown eggshell coloration. However, there have been no studies investigating hepatic functions of laying hens with variable intensity of brown eggshell color. Therefore, this study was aimed to identify potential factors affecting brown eggshell coloration in aged laying hens at the hepatic transcriptomic level. Methods: Five hundred 92-wk-old Hy-line Brown laying hens were screened to select laying hens with different intensity of brown eggshell color based on eggshell color fans. Based on eggshell color scores, hens with dark brown eggshells (DBE; eggshell color fan score = 14.8) and hens with light brown eggshells (LBE; eggshell color fan score = 9.7) were finally selected for the liver sampling. We performed RNA-seq analysis using the liver samples through the paired-end sequencing libraries. Differentially expressed genes (DEGs) profiling was carried out to identify their biological meaning by bioinformatics. Results: A total of 290 DEGs were identified with 196 being up-regulated and 94 being down-regulated in DBE groups as compared to LBE groups. The Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed that these DEGs belong to several biological pathways including herpes simplex infection (toll-like receptor 3 [TLR3], cyclin-dependent kinase 1, etc.) and influenza A (TLR3, radical S-adenosyl methionine domain containing 2, myxovirus [influenza virus] resistance 1, etc.). Genes related to stress response (ceremide kinase like) and nutrient metabolism (phosphoenolpyruvate carboxy-kinase 1, methylmalonic aciduria [cobalamin deficiency] cblB type, glycine receptor alpha 2, solute carrier family 7 member 11, etc.) were also identified to be differentially expressed. Conclusion: The current results provide new insights regarding hepatic molecular functions related to different intensity of brown eggshell color in aged laying hens. These insights will contribute to future studies aiming to optimize brown eggshell coloration in aged laying hens.

• Journal of Dairy Science and Biotechnology
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• v.41 no.4
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• pp.179-190
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• 2023

Currently, various probiotics are being used to improve the nutrition of companion animals. They are widely sold as additives in companion animal foods because of the numerous gastrointestinal and immune health benefits for dogs and cats. Therefore, extensive research is being conducted to improve quality and safety during manufacturing and to extend the shelf life of companion animal foods by adding probiotics. The manufacturing process must be conducted such that the characteristics and efficacy of probiotics added to food are optimally beneficial for companion animals. Therefore, this review aims to address the overall characteristics of the probiotic strains used and to examine the various methods through which probiotics are added to companion animal foods.

• Korean Journal of Animal Reproduction
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• v.27 no.4
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• pp.287-297
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• 2003

The aim of this review is to give insight into the reproduction potential of the Korean native goat(KNG) doe. The mean age of the first estrus in the KNG doe is 141.24$\pm$18.l7 days. The length of the estrous cycle was recorded as being 20.58$\pm$2.63 days, with the mean duration of estrous period being 17.8$\pm$7.3 to 32.9$\pm$1.2 h, and the duration of the post-partum anestrous period being 13.4(9 to 18) to 30.1$\pm$3.8 days in the KNG doe. The ages at first delivery are 10 to 12 months(56.3％) in the KNG doe. The KNG does are no restricted breeding season, because estrus and kiddings are observed throughout the year. The mean gestation period of the KNG doe is recorded as being 150.69$\pm$6.14 days with parities having no significant effect on gestation length. The mean interval between parturitions in the KNG doe is 207.78$\pm$1.72 days with parities and birth type having no significant effect on kidding intervals. The mean litter sizes at birth in the KNG doe are 1.69$\pm$0.03 heads, and litter size at birth was affected (P<0.05) by parity. The mean birth weight of kid in the KNG is 2.04$\pm$0.30 kg with a variety as being 2.28$\pm$0.26, 2.11$\pm$ 0.30 and 1.64$\pm$0.19 kg for singles, twins and triplets over of birth type, respectively. The mean mortality of 635 kids in the KNG is 23$\pm$1 ％ with a variety as being 28$\pm$3, 21$\pm$2, 16$\pm$3 and 46$\pm$15 ％ for singles, twins, triplets and quadruplets of birth type, respectively.

• Parasites, Hosts and Diseases
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• v.56 no.6
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• pp.597-602
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• 2018

Histomonas meleagridis is a facultative anaerobic parasite, which can cause a common poultry disease known as histomoniasis. The species and age of the birds impacts on the susceptibility, with turkey being the most susceptible species. Chickens are less susceptible to H. meleagridis than turkeys and usually serve as reservoir hosts. Here, the diagnosis of an outbreak of histomoniasis in backyard Sanhuang chickens is described. The primary diagnosis was made based on clinical symptoms, general changes at necropsy, histopathology, and the isolation and cultivation of parasites. The pathogen was further confirmed by cloning, PCR identification, and animal inoculation tests. A strain of H. meleagridis, named HM-JSYZ-C, with a higher pathogenicity level in chickens was obtained. The study lays a foundation for further investigations into H. meleagridis and histomoniasis in chickens.

• Animal Bioscience
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• v.36 no.2_spc
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• pp.364-373
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• 2023

The gastrointestinal (GI) tract of ruminants contains diverse microbes that ferment various feeds ingested by animals to produce various fermentation products, such as volatile fatty acids. Fermentation products can affect animal performance, health, and well-being. Within the GI microbes, the ruminal microbes are highly diverse, greatly contribute to fermentation, and are the most important in ruminant nutrition. Although traditional cultivation methods provided knowledge of the metabolism of GI microbes, most of the GI microbes could not be cultured on standard culture media. By contrast, amplicon sequencing of 16S rRNA genes can be used to detect unculturable microbes. Using this approach, ruminant nutritionists and microbiologists have conducted a plethora of nutritional studies, many including dietary interventions, to improve fermentation efficiency and nutrient utilization, which has greatly expanded knowledge of the GI microbiota. This review addresses the GI content sampling method, 16S rRNA gene amplicon sequencing, and bioinformatics analysis and then discusses recent studies on the various factors, such as diet, breed, gender, animal performance, and heat stress, that influence the GI microbiota and thereby ruminant nutrition.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.113-121
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• 1992

An the livestock production in Japan is industrialized, a tremendous amount of animal wastes is being produced annually, resulting in serious environmental pollution problems. Animal wastes could be pollutants, but they are also important sources of fertilizer nutrients and organic matter. Composting is an effective way of promoting the increased utilization of animal wastes. The characterization of maturing process during composting is important in order to improve the composting technology and to develop and efficient method to estimate the degree of maturity. The rise and fall in temperature, and changes in the constituents of the compost, reflect the maturing process and may serve as indicators for maturation. In addition, the detection of nitrate by diphenylamine, the determination of cation-exchange capacity (CEC), and the germination test, are also recommended as the methods of estimating the degree of maturity. The heavy applications of animal manure and compost may cause an adverse effect on soils and crops. When excess manure is applied, the nitrogen will be accumulated in soil, resulting in accumulation of nitrate in crops and pollution of the groundwater. Guidelines for application rates are recommended, to maintain soil productivity and quality of crops, and to prevent the environmental pollution.

• Korean Journal of Veterinary Service
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• v.43 no.4
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• pp.267-271
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• 2020

The emergence of highly contagious viral diseases of livestock and poultry such as foot-and-mouth disease (FMD), African swine fever (ASF) and highly pathogenic influenza (HPAI) have necessitated the formulation of policies and regulatory frameworks for preventing ingress of exotic diseases and controlling dissemination of endemic diseases within the country. The disease control ratings to manage contagious livestock disease in farms have not being widely used because the evaluation parameters were not being considered inappropriate. The purpose of this study was to reinforce the validity of the parameters for evaluation factors and the objectivity of the scoring criteria in the application of the current disease management rating system. The diseases subject to intensive management were improved by reflecting farm situation. For the evaluation based on the disease grading system of farms, the diseases subject to intensive management were realized, the list of diseases for evaluating the vaccination rate was revised, and the quarantine and sanitation management standards were revised. The effectiveness of the improved livestock disease management system was confirmed through the application of actual pig farms. Therefore, this system will be used as a means to evaluation the biosecurity at the farm units. Through this, it will contribute to establish effective biosecurity measures for each farm by improving and supplementing the present disease grading system.

• Clinical and Experimental Vaccine Research
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• v.12 no.4
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• pp.291-297
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• 2023

Enterovirus infections induce infectious diseases in young children, such as hand, foot, and mouth disease which is characterized by highly contagious rashes or blisters around the hands, feet, buttocks, and mouth. This predominantly arises from enterovirus A71 or coxsackievirus A16 infections and in severe cases, they can lead to encephalitis, paralysis, pulmonary edema, or even fatality, representing a global health threat. Due to the absence of effective therapeutic strategies for these infections, various experimental animal models are being investigated for the development of vaccines. During the early stages of research on enterovirus infections, non-human primate infections exhibited symptoms like those in humans, leading to their utilization as model animals. However, due to economic and ethical considerations, their current usage is limited. While enterovirus infections do not readily occur in mice, an infection model with mouse-adapted strain in neonatal mice has been employed. Cellular receptors have been identified in human cells, and genetically modified mice expressing these receptors have been used. Most recently, the utilization of Mongolian gerbil model is actively being considered and should be pursued for further animal model development. So, herein, we provide a summarized overview of the current portfolio of available enterovirus infection models, emphasizing their respective advantages and limitations.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1188-1191
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• 2004

Two species of marine catfish, Arius maculatus and Osteogeneiosus militaris, belonging to family Ariidae were analysed electrophoretically for genetic variation in 6 enzymes, alcohol dehydrogenase (ADH), malate dehydrogenase (MDH), lactate dehydrogenase (LDH), glucose dehydrogenase (GDH), malic enzyme (ME) and superoxide dismutase (SOD). Eighteen individuals of each species were studied. Two loci MDH and ADH were polymorphic in both. Average heterozygosity in A. maculatus was 1.46, while it was 2.5 in O. militaris. The allele frequencies were used to estimate Nei's genetic distance (D). The D value was calculated to be 0.6879. Two isozyme loci, ME and SOD, were found to be the most reliable species specific markers. No tissue specific loci were observed for the enzymes studied, the bands being identical in each case. The genetic distance observed between O. militaris and A. maculatus in this study suggests that they would be more appropriately classified as species of the same genus rather than being assigned separate genera.

• BMB Reports
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• v.53 no.8
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• pp.437-441
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• 2020

In accordance with requirements of the ICH S7B safety pharmacology guidelines, numerous next-generation cardiotoxicity studies using human stem cell-derived cardiomyocytes (CMs) are being conducted globally. Although several stem cell-derived CMs are being developed for commercialization, there is insufficient research to verify if these CMs can replace animal experiments. In this study, in vitro high-efficiency CMs derived from human embryonic stem cells (hESC-CMs) were compared with Sprague-Dawley rats as in vivo experimental animals, and primary cultured in vitro rat-CMs for cardiotoxicity tests. In vivo rats were administrated with two consecutive injections of 100 mg/kg isoproterenol, 15 mg/kg doxorubicin, or 100 mg/kg nifedipine, while in vitro rat-CMs and hESC-CMs were treated with 5 μM isoproterenol, 5 μM doxorubicin, and 50 μM nifedipine. We have verified the equivalence of hESC-CMs assessments over various molecular biological markers, morphological analysis. Also, we have identified the advantages of hESC-CMs, which can distinguish between species variability, over electrophysiological analysis of ion channels against cardiac damage. Our findings demonstrate the possibility and advantage of high-efficiency hESC-CMs as next-generation cardiotoxicity assessment.