• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2000년도 수정란의 위생적 처리·검사 및 특수가축의 수정란이식 기술 심포지움
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• pp.64-75
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• 2000

During the last three decades considerable advances has been made in goat embryo production and transfer technology. The Korean native black goat is the most useful domestic ruminant in this country for biological investigation and application because it has a lot of merits such as relatively short generation period(1 vs 2 year for a cow), easy of handling, well adaptation, high fertility, convenient and inexpensive. This article covers the methods of superovulation, estrus synchronization, embryo collection and transfer techniques, pregnancy diagnosis and subsequent pregnancy and kidding rates for the production of transgenic Korean native black goats. More than one hundred goat kids have been produced as a result of our transgenic goat project via microinjection of foreign gene into pronuclei, in vitro culture, transfer of various stages of fresh and frozen-thawed microinjected embryos into oviducts or uteri of recipient does. We have got two transgenic goats carrying a transgene targeting the expression of recombinant human granulocyte colony stimulating factor(hG-CSF) to the mammary gland so far. Since collection and transfer of embryos in this species is usually accomplished by laparotomy, exteriorization of the reproductive tract for surgical embryo collection leads to the formation of post-operative adhesions. Nonsurgical or laparoscopic technique to reduce adhesions from repeated surgeries has great advantages in improving embryo production and transfer especially from valuable donors. We will discuss this later.

• 대한수의학회지
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• 제39권3호
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• pp.399-406
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• 1999

The development of uterus in fetuses on 60, 90 and 120 days of gastation and neonates of Korean native goats was investigated by scanning electron microscopy. The results were summarized as follows ; 1. In the 60-day-old fetuses, the short microvilli were sporadically observed on the luminal surface of the endometrium. 2. In the 90-day-old fetuses, the mucosal folds, polygonal microridges, numerous microvilli, flower-like-buds, and domeshaped or crateriform area were also observed on the luminal surface of endometrium. 3. In the 120-day-old fetuses, the primordial caruncles(nodules) of the endometrium were developed conspicuously and long microvilli were developed densely. 4. In the neonates, the caruncles and microvilli of the endometrium were more developed than those of 120-day-old fetuses.

• 한국가축번식학회지
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• 제11권3호
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• pp.189-195
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• 1987

This study was conducted in order to obtain the information of the histological changes in each of six segments of the epididymal ducts in Korean native goats. Thirty-two Korean native male goats were examined, dividing into seven groups, at 4 weeks intervals from 8 to 32 weeks of age. The results obtained were as follows. 1. The epididymal ducts showed histologically an abrupt growth at the age of 16 weeks being followed by almost full maturation at the age of 24 weeks. Diameter of the cauda was steadily larger than that of the caput and corpus of the epididymal ducts. 2. Spermatozoa in the lumen of epididymal ducts were first observable at the age of 16 weeks, thereafter showing sparse in the lumen of caput, whereas most dense in the lumen of cauda in the density of spermatozoa. 3. Ducts in the caput and corpus were lined by ciliated columnar epithelium until the age of 12 weeks, and later by pseudostratified ciliated columnar epithelium which was composed of ciliated columnar cells, clear cells and basal cells. Ducts of cauda epididymis were lined by simple ciliated columnar epithelia until 12 weeks of age and later by simple or pseudostratified ciliated columnar epithelium, and two types of ducts (small ducts with high epithelium and large ducts with lower epithelium) were noted. Nucleus of the epithelial cells in the caput were located in the base of cells but in the corpus and cauda, those were located in the mid part of cells. cilia were most developed in the epithelia of the corpus.

• 한국가축번식학회지
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• 제9권1호
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• pp.56-61
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• 1985

This study was conducted in order to obtain the number and size of Leydig cell in the testis in accordance with the growth of Korean native goat. Twenty-one Korean native male goats were examied, and was divided into seven groups by 4 weeks interval from 8 to 32 weeks of age. The results were as follows: 1. The number of Leydig cells in the interstitial tissue were increased in accordance with age. The number of cells were increased twice from 1.3 cells at 8 weeks to 2.6 cells at 12 weeks of age, from 2.6 cells at 12 weeks to 5.5 cells at 24 weeks, respectively. And the cells were slightly increased from 5.5 cells at 16 weeks to 6.7 cells at 32 weeks. 2. The smallest cells were found in goats at 8 weeks of age, being 8.2${\mu}$m, and it showed noncontinual growth among groups of 12, 16 and 20 weeks of age, recording 9.18, 8.82 and 9.05${\mu}$m respectively. Leyding cells in 24, 28 and 32 weeks of age showed matured size being 10.42, 10.81 and 10.67${\mu}$m respectively. 3. Rows or clusters of Leydig cells were scattered in the loose connective tissue around lymphatic simusoids and blood vessels. Nuclei of Leydig cells were found to have 2 types, one type was stained pale and the other were stained dark. As a result of this study, Leydig cells found in the interstitial tissue were considered to grow until 20 weeks of age after birth, and reached to almost full maturated form by 24 weeks of ages.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1374-1377
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• 2004

The present study was conducted to explore the possibilities of estrus induction and superovulation in a native Indian breed of goats called 'Black Bengal'. Forty-two adult non-pregnant females were divided in two groups, of which 18 goats were subjected to a superovulatory treatment comprising of equine chorionic gonadotropin (eCG), Prostaglandin (PGF2$\alpha$) and human chorionic gonadotropin (hCG) to induce superovulation. The remaining 24 goats received no treatment and served as controls for the parameter under study as well as recipients for embryo transfer studies. The average duration of estrus was found to be significantly increased in treated goats (34.2${\pm}$3.4 h) compared to controls 3.0${\pm}$2.4 h). The average duration between PGF administration and occurrence of estrus was 2.0${\pm}$5.2 h. After mid ventral laparotomy, superovulatory responses indicated a significant increase in the number of follicles, which was 8.27${\pm}$0.37 in the treatment group compared to 4.16${\pm}$0.17 in the control group. The number of corpora lutea was also significantly increased in treated animals compared to control (2.90${\pm}$0.86 vs. 0.74${\pm}$0.04) respectively per ovary per goat.

• Asian-Australasian Journal of Animal Sciences
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• 제7권2호
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• pp.289-294
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• 1994

This report deals with the effect of levels of concentrate supplementary feeding (Nil, 0.25% BW and 0.75% BW) on the productivity of different genotypes (Thai native (TN), 25% Anglo-Nubian (AN), 50% AN and 75% AN) of female goats grazing newly established pasture in a tropical area. The major species of grass was Brachiaria mutica (33%) and of legumes was Centrosema pubescens (34%). There was no significant (p>0.05) difference between nil and 0.25% BW supplementary feeding for growth rate ($g/kg^{0.75}/d$). However, goats fed 0.75% BW supplementary feeding had significantly (p<0.01) higher growth rates than did other treatments. There was no significant (p>0.05) difference among genotypes and between age for growth rate. There was no interaction between feeding and genotype for growth rate.

• 한국초지조사료학회지
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• 제19권3호
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• pp.197-202
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• 1999

바랭이(Digitaria sanguinalis L.) 우점 야초지의 건물수량, 사료가치 및 영양소 이용성 등을 구명하여 조사료원으로 활용 가능성을 탐색하고자 숙기별 건물수량, 화학적 성분을 조사하였고, 재래산양 12두를 공시하여 혼파목초와 바랭이 우점 야초를 급여하여 섭취량, 건물소화율 및 질소와 에너지 이용성 등을 평가한 결과는 다음과 같다. 바랭이 우점 야초지의 평균 건물수량은 8,473kg/ha이었으며, 평균 CP, NDF, ADF 및 lignin 함량은 각각 13.0%, 74.1%, 38.6% 및 10.4%이었다. 건물섭취량은 바랭이 우점 야초지가 혼파초지에 비하여 다소 낮은 편이었으나 두 처리간에 유의적인 차이는 없었다. 그러나 건물소화율, 세포내용물의 소화율, NDF 및 ADF 소화율은 바랭이 우점 야초지가 혼파초지에 비하여 낮은 결과를 보였다(P<0.05). 질소 및 에너지의 이용성은 바랭이우점 야초지가 혼파초지에 비하여 낮았다(P<0.05). 이상의 결과로 보아 바랭이 우점 야초지는 혼파초지에 비하여 건물섭취량과 소화율 및 질소와 에너지이용성 등이 다소 낮은 편이지만, 시비를 하지 않고 연간 8,473kg/ha의 건물수량을 얻을 수 있어 부존 조사료원의 하나로 이용 가능성은 크다고 하겠다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권2호
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• pp.383-388
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• 1992

Nutritional status of macro minerals (Ca, Mg and P) in goats grazed on the native pasture was investigated for 2 years in Luzon Island, Republic of the Philippines. Three regions in Luzon Island (Los Banos; Southern area, Munoz, Nueva Ecija; Central area and Baguio; Northern area) were objected to collect the samples of forages and blood of goats on the pasture. The average values in Ca, Mg and P contents of all the forage samples were 0.29-1.32, 0.13-0.56 and 0.15-0.45% of dry matter, respectively, and these figures almost exceeded the required dietary levels for sheep. There was no obvious changes in mineral content of forages between the seasons of rainy and dry, or among regions. In blood Ca level, more than a half of goats (57.9%) without supplement showed the level below the lower limit, and the low level was not improved even when they fed with some supplemental concentrates. The plasma levels of Mg and P were satisfactory, referring to the lower limit of normal level in goats. It is, therefore, necessary to decide the requirement and to establish a most suitable technique for supplying Ca to grazing goats in Luzon Island.

• Animal Bioscience
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• 제34권6호
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• pp.1022-1028
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• 2021

Objective: Supplemental nitrate is known to be an effective tool to mitigate methane emission by ruminants. Based on theoretical considerations, supplemental nitrate can improve but also deteriorate the growth performance. The overall effect of supplemental nitrate on growth performance, however, is not yet known. The objective of the current study was therefore to evaluate the effect of a higher dose of NO3- on overall growth performance when feeding either Pangola grass hay or rice straw. Methods: Thirty-two crossbred, 3-month-old Thai native×Anglo-Nubian crossbred male goats were used. The experiment had a 2×2 factorial design with an experimental period of 60 days. Eight goats were randomly allocated to each dietary treatment, i.e. a ration containing either Pangola hay (Digitaria eriantha Steud) or rice straw (Oryza Sativa) as a source of roughage, supplemented with a concentrate containing either 3.2% or 4.8% potassium nitrate. The rations were formulated to be isonitrogenous. The animals were weighed at the start of the experiment and at days 30 and 60. Feces were collected during the last five days of each 30-day period. Results: High-nitrate increased overall DM intake by approximately 3%, irrespective the source of roughage, but only the goats fed a rice straw-based ration responded with an increase in body weight (BW). Thus, the overall feed conversion ratio (kg feed/kg BW gain) was influenced by roughage source ×nitrate and decreased by almost 60% when the goats were fed rice straw in combination with a high versus a low dietary nitrate content. The digestibility of macronutrients was only affected by the source of roughage and the digestibility of organic matter, crude protein, and neutral detergent fibre was greater when the goats were fed Pangola hay. Conclusion: It was concluded that the replacement of soybean meal by nitrate improves the growth performance of meat goats fed rations based on rice straw, but not Pangola hay.

• 한국유기농업학회지
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• 제13권1호
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• pp.85-99
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• 2005

This trial was carried out to determine effects of organic feeds in comparison to conventional diet on feed intake, digestibility, and nitrogen retention in Korean native goats. Twelve Korean native goats were allotted to treatments in four groups of three goats and then they were housed in separate metabolism cages for 21 days. Treatments included conventional diet (A) as a control group and three organic feed groups (B: organic rice straw, C: organic nee leaves, D: organic mixture of rice straw and tree leaves). The A treatment, conventional diet, consisted of common rice straw and commercial concentrates at a proportion of 60 and 40%, respectively. All ingredients of organic feeds treatments were organically produced-agricultural products without any application of chemical fertilizer and pesticide. Four experimental diets were formulated to have the same ratio of forage to concentrate and similar contents for protein and carbohydrate across treatments and they were offered to goats ad libitum. Feed intake, apparent nutrient digestibility and nitrogen retention were investigated. For chemical compositions of experimental diets, all nutrients except crude ash and ether extract were not significantly different across treatments as we expected. Crude ash content was highest in the A treatment (P<0.05), however, it was not significantly different among organic feeds treatments. Ether extract content was higher (P<0.05) in C and D treatments than in A and B. Even if dry matter intakes for organic feeds treatments were not significantly different among them, they were significantly higher (P<0.05) compared with conventional diet. Fecal excreta were not significantly different across treatments, resulting in significantly higher digestible dry matter (g/day) in treatments of organic feeds (P<0.01). Average daily gain (ADG) and feed efficiency (FE) were more increased (P<0.01) in treatments of organic feeds compared with conventional diet. Digestibilities for most of nutrients except NFC had the same trend as ADG and FE, however, NFC digestibilities for C and D treatments were significantly lower (P<0.01) than those of A and B. Nitrogen intakes for organic feeds treatments were significantly higher (P<0.001) than conventional diet, with no difference among organic feeds treatments. Fecal nitrogen loss was higher (P<0.05) for C and D treatments than for A and B. Retained nitrogen contents were significantly higher (P<0.05) for organic feeds treatments than for conventional diet, but nitrogen retention rate did not show any difference across treatments. The results showed that organic feed supplementation more improved feed intake, digestibility and nitrogen retention in comparison with conventional diet, and thus they could be concluded that organic feeds might contribute to animal performance and a safer production of animal product.