• Asian-Australasian Journal of Animal Sciences
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• 제16권7호
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• pp.1071-1086
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• 2003

Reproductive biotechnologies continue to be developed for genetic improvement of both river and swamp buffalo. Although artificial insemination using frozen semen emerged some decades back, there are still considerable limitations. The major problem appears to be the lack of efficient methods for estrus detection and timely insemination. Controlled breeding experiments in the buffalo had been limited and similar to those applied in cattle. Studies on multiple ovulation and embryo transfer are essentially a replica of those in cattle, however with inherent problems such as lower number of primordial follicles on the buffalo ovary, poor fertility and seasonality of reproduction, lower population of antral follicles at all stages of the estrous cycle, poor endocrine status and a high incidence of deep atresia in ovarian follicles, the response in terms of transferable embryo recovery has remained low with 0.51 to 3.0 per donor and pregnancy rates between 15 to 30%. In vitro production of buffalo embryos is a valid alternative to recovery of embryos by superovulation. This aspect received considerable attention during the past decade, however the proportion of embryos that develops to the blastocyst stage is still around 25-30% and hence the in vitro culture procedures need substantial improvement. Embryo cryopreservation procedures for direct transfer post thaw need to be developed for bubaline embryos. Nuclear transfer and embryo cloning is a technique that has received attention in various species during recent years and can be of immense value in buffaloes as they have a low rate of embryo recoveries by both in vitro and in vivo procedures. Gender pre-selection, genome analysis, gene mapping and gene transfer are a few of the techniques that have been studied to a limited extent during recent years and are likely to be included in future studies on buffaloes. Very recently, reproductive biotechnologies have been applied to feral buffaloes as well, but the results obtained so far are modest. When fully exploited they can play an important role in the preservation of endangered species.

• The Plant Pathology Journal
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• 제33권5호
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• pp.458-466
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• 2017

Xanthomonas oryzae pv. oryzae (Xoo), the causative agent of bacterial blight, is a major threat to rice productivity. Here, we performed RNA-Seq based transcriptomic analysis of Xoo transcripts isolated under in planta growth (on both susceptible and resistant hosts) and in vitro culture conditions. Our in planta extraction method resulted in successful enrichment of Xoo cells and provided RNA samples of high quality. A total of 4,619 differentially expressed genes were identified between in planta and in vitro growth conditions. The majority of the differentially expressed genes identified under in planta growth conditions were related to the nutrient transport, protease activity, stress tolerance, and pathogenicity. Among them, over 1,300 differentially expressed genes were determined to be secretory, including 184 putative type III effectors that may be involved in Xoo pathogenicity. Expression pattern of some of these identified genes were further validated by semi-quantitative RT-PCR. Taken together, these results provide a transcriptome overview of Xoo under in planta and in vitro growth conditions with a focus on its pathogenic processes, deepening our understanding of the behavior and pathogenicity of Xoo.

• Journal of Ginseng Research
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• 제40권4호
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• pp.409-414
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• 2016

Background: The low survival rate of in vitro regenerated Panax ginseng plantlets after transfer to soil is the main obstacle for their successful micropropagation and molecular breeding. In most cases, young plantlets converted from somatic embryos are transferred to soil. Methods: In vitro thickened taproots, which were produced after prolonged culture of ginseng plantlets, were transferred to soil. Results: Taproot thickening of plantlets occurred near hypocotyl and primary roots. Elevated concentration of sucrose in the medium stimulated the root thickening of plantlets. Senescence of shoots occurred following the prolonged culture of plantlets. Once the leaves of plantlets senesced, the buds on taproots developed a dormant tendency. Gibberellic acid treatment was required for dormancy breaking of the buds. Analysis of endogenous abscisic acid revealed that the content of abscisic acid in taproots with senescent shoots was comparatively higher than that of taproots with green shoots. Thickened taproots were transferred to soil, followed by exposure to gibberellic acid or a cold temperature of $2^{\circ}C$ for 4 mo. Cold treatment of roots at $2^{\circ}C$ for 4 mo resulted in bud sprouting in 84% of roots. Spraying of 100 mg/L gibberellic acid also induced the bud sprouting in 81% roots. Conclusion: Soil transfer of dormant taproots of P. ginseng has advantages since they do not require an acclimatization procedure, humidity control of plants, and photoautotrophic growth, and a high soil survival rate was attained.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.295-302
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• 2011

Almost half of New Zealand's greenhouse gas emissions arise from agriculture and enteric methane ($CH_4 $) emissions arising from ruminant animals constitute 30% of total $CO_2$-e emissions. Enteric $CH_4$ emissions have increased by 9% since 1990. Extensive research has been undertaken to develop reliable methods for measuring enteric $CH_4$ emissions. New Zealand studies using the SF6 tracer technique suggest that on average this technique yields similar values to the 'gold' standard of calorimetry, but with a larger variance. National inventory estimates based on results obtained using the $SF_6$ technique will therefore overestimate the uncertainty. Mitigating emissions can be achieved by changing feed type but there are practical and cost barriers to the use of alternative feeds. Forages containing condensed tannins do reduce emissions but are agronomically inferior to the forages currently used. Rumen additives have shown some success in-vitro but results from in-vivo trials with both monensin and fumaric acid have been disappointing. The development of methods for directly manipulating rumen microorganisms are at an early stage and work to develop vaccines that can inhibit methanogenesis has yielded mixed results. The successful identification of sheep with contrasting $CH_4$ yields raises the possibility that, in the long term, a breeding approach to $CH_4$ mitigation is feasible.

• 한국양식학회지
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• 제9권1호
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• pp.57-63
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• 1996

범가자미 난모세포의 최종성숙(GVBD=germinal vesicle breakdown) 유도를 위한 HCG (human chorionic gonadotropin)와 스테로이드 호르몬들의 효능 비교실험이 in vitro에서 이루어졌다. 실험에 사용한 스테로이드 호르몬, progestogens (progesterone, $17\alpha$-hydroxyprogesterone, $17\alpha$-hydroxy, $20\beta$-dihydroprogesterone)중에서는 $17\alpha$-hydroxy, $20\beta$-dihydroprogesterone ($17\alpha20{\beta}OHP$)이 매우 효과적으로 나타났으며, $17\alpha20{\beta}OHP$와 HCG와의 비교실험에서는 이들 모두 GVBD 유도에 효과적인 것으로 나타났다. 특히 $17\alpha20{\beta}OHP$는 저농도($10\~50$ ng/ml)에서도 효과적이며, HCG는 사용한 농도(50, 100, 500 IU/ml)사이에 유의한차를 보이지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권12호
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• pp.1587-1593
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• 2010

Pastures of the Apennines of Central Italy contribute to feed resources of high altitude (above 1,300 m sea level) grazing systems. The objective of this study was to evaluate the effectiveness of faecal extract from the yak (Bos grunnienes) as an alternative microbial inoculum to rumen fluid for estimation of digestibility of several forage species. Forage samples produced at high altitude were tested in this study: four legumes (Lathyrus sativus L., Lotus corniculatus L., Onobrychis viciaefolia L. and Trifolium pratense L.), three forbs (Achillea millefolium L., Potentilla reptans L. and Teucrium flavum L.) and one grass (Brachipodyum pinnatum L.) were incubated with yak rumen fluid or faecal extract. A large variability in chemical composition was observed among the species collected. Rumen liquor and faecal samples were collected from adult healthy yak. The $Daisy^{II}$ incubator was used to evaluate the nutrient digestibility of forages using rumen liquor as control and faecal extract as alternative microbial inoculum sources. Filter bags containing samples of browse species were added to the four digestion vessels along with their respective inoculum and then incubated for 48 h and dry matter (DM), organic matter (OM), crude protein (CP), neutral and detergent fiber (NDF) digestibility was determined. There was a significant relationship between estimates, indicating that faecal liquor has the potential to be used instead of rumen fluid for estimation of in vitro digestibility of plants. It is concluded that the $Daisy^{II}$ incubator results are appropriate for the determination of in vitro digestibility of nutrients using faecal liquor to define the potential for adaptation of yak to new pastures.

• 한국자원식물학회지
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• 제25권2호
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• pp.225-231
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• 2012

둥근마 액체배양에서 소괴경의 생산을 위하여 배양온도와 일장의 전환과 배양 배지의 교체 효과를 조사하였다. 둥근마 액체배양에서 식물체의 증식을 위한 일장시간은 6주의 배양기간 동안 $25^{\circ}C$에서 16시간보다는 24시간이 효과적이었다. 기내소괴경의 생산을 위하여 배양기간을 12주로 연장하여 배양하였으며, 배지교체의 효과를 검토하기 위하여, 배양 중기인 배양 후 6주째에 새로운 배지로 교체하였더니, 배지를 교체하지 않은 것보다 소괴경의 형성수가 평균 5개씩 더 많았고, 소괴경무게도 70% 이상 증가하였다. 배양환경의 전환이 소괴경 형성에 미치는 효과를 알아보기 위하여, 12주의 배양기간 중에 식물체 생장이 활발한 초기 6주간은 $25^{\circ}C$에서 24시간의 일장환경에서 배양하고, 이후 6주간의 배양온도와 일장시간을 전환하였다. 배양온도는 $25^{\circ}C$가 $15^{\circ}C$보다 효과적이었고, $25^{\circ}C$에서 일장시간은 24시간이 암처리 또는 8시간 일장처리보다 효과가 있었다. 12주간의 배양기간중에 배지 교체의 적절한 시기는 배양 후 2, 4, 6, 8, 10주째 또는 배지 무교체 처리구중에서, 생체중, 마디수, 소괴경수에서는 2주 또는 6주째에 교체하는 것이 좋았고, 소괴경중은 8주째 교체 처리구에서 가장 무거웠으나 소괴경의 수와 무게를 모두 고려하였을 때, 초기 배양 후 6주째에 배지 교체하는 것이 가장 효율적이었다. 12주간의 배양기간 중 배양 후 6주째에 교체할 배지의 성분은 sucrose 30, 60 $g{\cdot}L^{-1}$ 또는 sucrose 60 g + BA 0.1 $mg{\cdot}L^{-1}$ 함유 배지 중에서 sucrose 60 $g{\cdot}L^{-1}$이 함유된 배지로 교체하였을 때, 소괴경의 총무게가 가장 무거워 소괴경의 비대에 가장 효과적이었다. 따라서, 둥근마의 액체배양시 $25{\pm}1^{\circ}C$, 24시간 광조건으로, 마디접종 후 6주째에 sucrose 60 $g{\cdot}L^{-1}$를 함유한 배지로 교체하여 6주간 추가 배양하는 방법이 기내 식물체와 소괴경의 생장과 형성에 가장 효과적이었다.

• 한국수정란이식학회지
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• 제24권3호
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• pp.159-167
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• 2009

Ultrasonographic examination was performed to observe the ultrasonographic image of Korean native cows' normal uterus in condition of in vitro and in vivo. The experiment was done 28 slaughtered cows' uterus using immersed in water in vitro, and 41 healthy breeding cows taken rectal ultrasonography in vivo. Ultrasonographic examination of uterine was taken on the reference of cross section of intercornual ligaments' cranial. Each uterus on the experiments was compared by estrous cycle and ultrasonographic frequency. The uterine structure using ultrasonography was 5 layers of uterine horn in vivo as well as in vitro. Uterine horn was observed to be distinguished from inside to outside as endometrium to inner echogenic layer, circular muscle layer to slightly echogenic elliptical layer, stratum vasculare to central echogenic layer, longitudinal muscle layer to slightly echogenic arched layer, and perimetrium to outer echogenic layer, respectively. According to the observation of uterus related to estrous cycle and ultrasonographic examination, uterine endometrium in vitro was constantly founded irrespective of estrous cycle and ultrasonographic frequency. On the low frequency, endometrium and circular muscle layer in estrus were prone to distinguished than in diestrus. On the high frequency, endometrium and circular muscle layer were always distinguished regardless of estrous cycle. In vivo, uterine endometrium and circular muscle layer were observed regardless of estrus and ultrasonographic frequency. On the low frequency, stratum vasculare and longitudinal muscle layer were not likely to be distinguished in diestrus, but estrus. On the high frequency, stratum vasculare and longitudinal muscle layer were observed regardless of estrous cycle. Also, every uterine structure was easily distinguished on high frequency than low frequency owing to precision of distinction in layers. The difference of results followed by the experiments conditions between in vitro and in vivo was that uterine endometrium and circular muscle layer in diestrus in vitro were difficult to be distinguished and uterine lumen was observed during whole estrous cycle. In vivo, It was founded that the distinction of stratum vasculare and logitudinal muscle layer in diestrus was complicated and uterine lumen was observed during only estrus. In view of the result so far achieved, normal uterine structure divided in 5 layers on ultrasonography was accorded with microscopic organization, uterine structure was likely to be observed during estrus than diestrus, high frequency checkup than low frequency, and uterine endometrium, circular muscle, stratum vasculare was easily observed regardless of estrous cycle and ultrasonographic frequency.

• The Plant Pathology Journal
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• 제36권6호
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• pp.558-569
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• 2020

Fusarium head blight (FHB) is a devastating fungal disease of wheat (Triticum aestivum L.). The lack of genetic resources with stable FHB resistance combined with a reliable and rapid screening method to evaluate FHB resistance is a major limitation to the development of FHB resistant wheat germplasm. The present study utilized an immature wheat spike culture method to screen wheat spike culture derived variants (SCDV) for FHB resistance. Mycotoxin concentrations determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) correlated significantly (P < 0.01) with FHB severity and disease progression during in vitro spike culture. Selected SCDV lines assessed for FHB resistance in a Fusarium field disease nursery in Carman, Manitoba, Canada in 2016 showed significant (P < 0.01) correlation of disease severity to the in vitro spike culture screening method. Selected resistant SCDV lines were also crossed with an elite cv. CDC Hughes and the progeny of F₂ and BC₁F₂ were screened by high resolution melt curve (HRM) analyses for the wheat UDP-glucosyl transferase gene (TaUGT-3B) single nucleotide polymorphism to identify resistant (T-allele) and susceptible (G-allele) markers. The progeny from the crosses were also screened for FHB severity using the immature spike culture method and identified resistant progeny grouped according to the HRM genotyping data. The results demonstrate a reliable approach using the immature spike culture to screen for FHB resistance in progeny of crosses in early stage of breeding programs.

• 식물조직배양학회지
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• 제27권2호
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• pp.143-148
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• 2000

감 돌연변이 획득을 위해 기내배양 신초에 ${\gamma}$-선을 조사하여 변이유기를 위한 적정 선량, ${\gamma}$-선 조사 식물체의 기내 발근 및 생육 특성을 조사한 결과는 다음과 같다. 감 돌연변이 유기를 위한 적정한 조사 선량 (LD$_{50}$)은 서촌조생 품종에서 1 krad와 2 krad사이이었고, 일목계차랑 품종은 1 krad이었다. ${\gamma}$-선을 조사한 신초를 1차,2차, 3차에 걸쳐 계대배양하는 각 기간의 기내 생육상태를 보면 ${\gamma}$-선량이 증가할수록 기내에서 생장한 신초의 길이가 감소하였으며, 신초의 정아가 가장 장애를 많이 받았다. 서촌조생 품종에서 신초의 37.5~58.3% 정도가 발근되었고 발근율은 2 krad 처리에서는 가장 낮았다. ${\gamma}$-선 조사선량이 높아지면 발근율과 뿌리의 발생수가 줄어들었다. 순화한 뒤 6주 동안 생장상에서 생육한 ${\gamma}$-선 조사 개체는 무처리 개체의 묘고가 6.0 cm인데 비해 2krad 처리개체는 평균 묘고는 2.6 cm에 불과하였다. 또한 발생한 가지의 수도 무처리에서는 1.0개인데 비해 2krad에서는 1.8 개로 많았다. 온실 생육시에서 ${\gamma}$-선 처리선량이 높았던 개체는 처리되지 않았거나 낮았던 개체에 비해 묘고가 작고 분지수가 많았으며, 생육상태도 부진하여 생육 중에 33%정도만 생존하고 나머지는 고사하였다.다.