• 제목/요약/키워드: animal study

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Preliminary Study on the Level of Evolutionary Differentiation between Domestic Quails and Wild Japanese Quails

  • Wang, H.Y.;Chang, H.;Xu, W.;Chang, G.B.;Lu, S.X.;Du, L.;Sun, W.;Xu, M.;Wang, Q.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권2호
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    • pp.266-268
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    • 2003
  • This paper makes an analysis of the ecological behaviours of 3 categories of quails, namely wild Japanese quails from the Weishan Lake Area, medium-sized domestic quails and pint-sized domestic quails. The study indicates as follows: (1) There is difference in morphological and biological habits between domestic quails and wild Japanese ones. (2) The cross-breeding between the wild and domestic quails is a cross from exclusion to affinity. (3) The behaviours of quails such as pursuit,paw and mating are selective. (4) The wild Japanese quails and domestic ones can succeed in mating and in reproducing fertilized eggs but with a low rate. (5) Evolutionary differentiation has been formed in varying degrees between the domestic quails and their wild ancestors in morphological and ecological characteristics.

The Effect of Cryoprotectants on the Survival and In Vitro-Growth of Cryopreserved Mouse Preantral Follicles

  • Kim, Dong-Hoon;Chung, Duk-Soo;Lim, Hyun-Joo;Im, Gi-Sun;Lee, Hwi-Cheul;Seong, Hwan-Hoo
    • Reproductive and Developmental Biology
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    • 제32권2호
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    • pp.111-115
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    • 2008
  • The aim of this study was to examine more effective cryoprotectant for the cryopreservation of mouse preantral follicles. Enzymetically isolated preantral follicles from 12-day-old mice were cryopreserved by a slow freezing protocol with 1.5 M propanediol (PROH), dimethyl sulphoxide (DMSO) or glycerol (GLY) and then grown and matured in vitro for 11 days after thawing. The survival of preantral follicles immediately after freezing and thawing was not different among the PROH (68.2%), DMSO (72.4%) and GLY (72.1%). After grown and matured in vitro, the rates of survival and metaphase II oocytes were 54.9% and 36.6% for PROH which was significantly higher rates (p<0.05) compared with the rates obtained from DMSO (16.9% and 9.0%) and GLY (16.3% and 7.5%). The diameter of metaphase II oocytes from pre antral follicles frozen in PROH ($67.4{\pm}1.8\;{\mu}m$) was significantly (p<0.05) smaller than that of the fresh preantral follicles ($69.1{\pm}2.3\;{\mu}m$). The results from the present study revealed that PROH is more suitable cryoprotectant for the cryopreservation of mouse preantral follicles.

COMPARATIVE STUDY ON PANEER MAKING FROM BUFFALO AND COW MILK

  • Masud, T.;Athar, I.H.;Shah, M.A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권3호
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    • pp.563-565
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    • 1992
  • The objective of this study is to compare the qualitative and quantitative properties of paneer prepared from buffalo and cow milk. Paneer from buffalo milk had higher total solids as compared to cow. Moreover significant differences were recorded in fat and protein contents among tested samples of milk, cheese and whey respectively. The results of the organoleptic evaluations showed that paneer made from cow milk was liked more as compared to buffalo.

Impact of rumen cannulation surgery on rumen microbiota composition in Hanwoo steers

  • Minseok Kim;Tansol Park;Cheolju Park;Youl-Chang Baek;Ara Cho;Han Gyu Lee;Eunju Kim;Eun-Yeong Bok;Young-Hun Jung;Tai-Young Hur;Yoon Jung Do
    • Journal of Animal Science and Technology
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    • 제66권2호
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    • pp.353-365
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    • 2024
  • Rumen cannulation is a surgical technique used to collect rumen contents from ruminants. However, rumen cannulation surgery may potentially impact the composition of the rumen microbiota. This study aimed to examine the longitudinal alterations in the rumen microbiota composition of Hanwoo steers after cannulation surgery. In this study, eight Hanwoo steers were used; four steers underwent rumen cannulation surgery (cannulation group), while the remaining four were left intact (control group). Rumen samples were collected from all eight steers using the stomach tubing method on the day before surgery (day 0) and on postoperative days 1, 4, 7, 10, 14, 17, 21, 24, and 28, resulting in 80 samples (10 timepoints × 8 animals). The microbiota of all 80 samples were analyzed using 16S rRNA gene amplicon sequencing with Quantitative Insights into Microbial Ecology version 2 (QIIME2). There were no significant differences (p > 0.05) in all major phyla and most major genera representing at least 0.5% of total sequences across all 80 samples between the control and cannulation groups on the preoperative and postoperative days. However, while the alpha diversity indices did not differ (p > 0.05) between the two groups on the preoperative day, they significantly differed (p < 0.05) between the two groups on the postoperative days. Further, the overall microbial distribution based on both unweighted and weighted principal coordinate analysis plots significantly differed (p < 0.05) between the two groups on both the preoperative and postoperative days. Orthogonal polynomial contrasts indicated that major genera and microbial diversity in the cannulation group decreased following surgery but returned to their initial states by postoperative day 28. In conclusion, this study demonstrates that rumen cannulation surgery affects some major taxa and microbial diversity, suggesting that the rumen cannulation method can alter the composition of rumen microbiota in Hanwoo steers.

Effects of High Levels of Nutrients on Growth Performance and Carcass Characteristics of Hanwoo Cattle

  • Reddy, Kondreddy Eswar;Jeong, Jin Young;Ji, Sang Yun;Baek, Youl-Chang;Lee, Seul;Kim, Minseok;Oh, Young Kyun;Lee, Hyun-Jeong
    • 한국초지조사료학회지
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    • 제38권3호
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    • pp.180-189
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    • 2018
  • The present study was conducted to evaluate the effects of high levels of nutrients on the growth performance, blood metabolites and carcass characteristics of Hanwoo cattle. Eighteen Hanwoo steers were fed two types of diets: 1) Nine animals were fed the conventional diet including typical levels of crude protein (CP) and total digestive nutrients (TDN), and 2) Nine animals were fed the treatment diet including high levels of CP and TDN. The average body weight (BW) and dry matter intake (DMI) were greater (P < 0.05) in the treatment group than in the conventional group at early and late fattening stages. Also, in the treatment group, the average daily gain (ADG) was greater (P < 0.05) at the late fattening stage. The serum total lipid and cholesterol levels were higher (P < 0.05) in the late fattening stage of treatment group. The carcass weight, total fat weight, longissimus muscle area and the grade of meat quality were also greater (P < 0.05) in the treatment group than the conventional diet group. This study demonstrates that high levels of CP and TDN exhibit a positive effect on the growth performance and carcass characteristics, indicating that high levels of CP and TDN can be used as a cost-effective feeding program for Hanwoo cattle by shortening the feeding period.

Intravenous administration of L-tryptophan stimulates gastrointestinal hormones and melatonin secretions: study on beef cattle

  • Lee, Sang-Bum;Lee, Kyung-Won;Wang, Tao;Lee, Jae-Sung;Jung, U-Suk;Nejad, Jalil Ghassemi;Oh, Young-Kyoon;Baek, Youl-Chang;Kim, Kyoung Hoon;Lee, Hong-Gu
    • Journal of Animal Science and Technology
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    • 제61권4호
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    • pp.239-244
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    • 2019
  • This study aimed to determine the effective dose of intravenous administration of L-tryptophan (L-T) on gastrointestinal hormones (GIH) secretions and melatonin using Hanwoo cattle. Three steers ($362{\pm}23kg$) fitted with indwelling jugular vein catheters were assigned in a $3{\times}3$ Latin square design. Treatments were intravenous administration of saline (control), 28.9 mg L-T/kg body weight (BW; low) and 57.8 mg L-T/kg BW (high) L-T for 1 day with 7 days of adaptation. Samples were collected after adaptation period at -60, 0, 30, 60, 90, 120, 150, 180, 240, and 300 min of sampling day. The levels of serum cholecystokinin (CCK) and secretin were higher (p < 0.05) in the high L-T group than those in the other groups. Serum Melatonin (MEL) levels were increased upon L-T administration (p < 0.05) in the high L-T group. Taken together, the effective dose of L-T administration was defined at 57.8 mg L-T/kg BW in order to stimulate increase of GIH and MEL.

A comparative analysis of rumen pH, milk production characteristics, and blood metabolites of Holstein cattle fed different forage levels for the establishment of objective indicators of the animal welfare certification standard

  • Baek, Dong Jin;Kwon, Hyoun Chul;Mun, Ah Lyum;Lim, Joo Ri;Park, Sung Won;Han, Jin Soo
    • Animal Bioscience
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    • 제35권1호
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    • pp.147-152
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    • 2022
  • Objective: This study was conducted to obtain an objective index that can be quantified and used for establishing an animal welfare certification standard in Korea. For this purpose rumen pH, ruminating time, milk yield, milk quality, and blood components of cows reared in farms feeding high forage level (90%) and farms feeding low forage level (40%) were compared. Methods: Data on rumen pH, rumination time, milk yield, milk fat ratio, milk protein ratio, and blood metabolism were collected from 12 heads from a welfare farm (forage rate 88.5%) and 13 heads from a conventional farm (forage rate 34.5%) for three days in October 2019. Results: The rumination time was longer in cattle on the welfare farm than on the conventional farm (p<0.01), but ruminal pH fluctuation was greater in the cattle on conventional farm than the welfare farm (p<0.01). Conventional farms with a high ratio of concentrated feed were higher in average daily milk yield than welfare farms, but milk fat and milk production efficiency (milk fat and milk protein corrected milk/total digestible nutrients) was higher in cattle on welfare farms. Blood test results showed a normal range for both farm types, but concentrations of total cholesterol and non-esterified fatty acid were significantly higher in cows from conventional farms with a high milk yield (p<0.01). Conclusion: The results of this study confirmed that cows on the animal welfare farm with a high percentage of grass feed had higher milk production efficiency with healthier rumen pH and blood metabolism parameters compared to those on the conventional farm.

Epidemiological investigation and phylogenetic analysis of Classical Swine Fever virus in Yunnan province from 2015 to 2021

  • Yao, Jun;Su, Linlin;Wang, Qiaoping;Gao, Lin;Xie, Jiarui;He, Yuwen;Shu, Xianghua;Song, Chunlian;Chai, Jun;Zhang, Yifang;Yang, Shibiao
    • Journal of Veterinary Science
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    • 제23권4호
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    • pp.57.1-57.9
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    • 2022
  • Background: Classical swine fever virus (CSFV), the causative agent of classical swine fever (CFS), is a highly contagious disease that poses a serious threat to Chinese pig populations. Objectives: Many provinces of China, such as Shandong, Henan, Hebei, Heilongjiang, and Liaoning provinces, have reported epidemics of CSFV, while the references to the epidemic of CSFV in Yunnan province are rare. This study examined the epidemic characteristics of the CSFV in Yunnan province. Methods: In this study, 326 tissue samples were collected from different regions in Yunnan province from 2015 to 2021. A reverse transcription-polymerase chain reaction (RT-PCR), sequences analysis, and phylogenetic analysis were performed for the pathogenic detection and analysis of these 326 clinical specimens. Results: Approximately 3.37% (11/326) of specimens tested positive for the CSFV by RT-PCR, which is lower than that of other regions of China. Sequence analysis of the partial E2 sequences of eleven CSFV strains showed that they shared 89.0-100.0% nucleotide (nt) and 95.0-100.0% amino acid (aa) homology, respectively. Phylogenetic analysis showed that these novel isolates belonged to the subgenotypes 2.1c and 2.1d, with subgenotype 2.1c being predominant. Conclusions: The CSFV was sporadic in China's Yunnan province from 2015 to 2021. Both 2.1c and 2.1d subgenotypes were found in this region, but 2.1c was dominant.

Residual Level, Histology, and Blood Biochemistry of Tebuconazole: A Repeated Dose 28-Day Oral Toxicity Study in Pigs

  • Jeong, Jin Young;Kim, Minji;Park, Seol Hwa;Kim, Byeonghyeon;Oh, Sang-Ik;Kim, Eunju;Jung, Hyunjung
    • 한국축산식품학회지
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    • 제42권4호
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    • pp.712-722
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    • 2022
  • In this study, we investigated the residual properties of tebuconazole-treated pigs. Twenty pigs were treated with different concentrations (0.25, 1.25, 2.5, 12.5, and 25 mg/kg bw/d) of tebuconazole for 28 d. Blood biochemistry, histology, and residual levels were analyzed using the VetTest analyzer, Masson's trichrome staining kit, and liquid chromatography-mass spectrometry, respectively. The final body weights were not significantly different between the control and treatment groups. Alkaline phosphatase, blood urea nitrogen, cholesterol, and gamma-glutamyl transpeptidase levels were significantly different from those of the control after exposure for 14 d. However, alanine aminotransferase levels showed changes only after exposure to pesticides for 28 d. The biochemical parameters were separated during the experimental period (14 d versus 28 d) by principal component analysis. Based on variable importance plots, blood urea nitrogen/creatinine ratio, blood urea nitrogen, glucose, and gamma-glutamyl transpeptidase are candidate biomarkers for tebuconazole exposure. The residual levels were observed at T4 (12.5 mg/kg bw/d) and T5 (25 mg/kg bw/d) in the liver and fat tissues, respectively. Fibrosis increased in the liver, kidney, and fat tissues, depending on the tebuconazole concentration. In conclusion, the residue limits of tebuconazole and the physiological changes caused by dietary tebuconazole in pigs provide important information for establishing maximum residue limits of pork and pork products.

Analysis of antibiotic resistance genes in pig feces during the weaning transition using whole metagenome shotgun sequencing

  • Gi Beom Keum;Eun Sol Kim;Jinho Cho;Minho Song;Kwang Kyo Oh;Jae Hyoung Cho;Sheena Kim;Hyeri Kim;Jinok Kwak;Hyunok Doo;Sriniwas Pandey;Hyeun Bum Kim;Ju-Hoon Lee
    • Journal of Animal Science and Technology
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    • 제65권1호
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    • pp.175-182
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    • 2023
  • Antibiotics have been used in livestock production for not only treatment but also for increasing the effectiveness of animal feed, aiding animal growth, and preventing infectious diseases at the time when immunity is lowered due to stress. South Korea and the EU are among the countries that have prohibited the use of antibiotics for growth promotion in order to prevent indiscriminate use of antibiotics, as previous studies have shown that it may lead to increase in cases of antibiotic-resistant bacteria. Therefore, this study evaluated the number of antibiotic resistance genes in piglets staging from pre-weaning to weaning. Fecal samples were collected from 8 piglets just prior to weaning (21 d of age) and again one week after weaning (28 d of age). Total DNA was extracted from the 200 mg of feces collected from the 8 piglets. Whole metagenome shotgun sequencing was carried out using the Illumina Hi-Seq 2000 platform and raw sequence data were imported to Metagenomics Rapid Annotation using Subsystem Technology (MG-RAST) pipeline for microbial functional analysis. The results of this study did not show an increase in antibiotic-resistant bacteria although confirmed an increase in antibiotic-resistant genes as the consequence of changes in diet and environment during the experiment.