• Asian-Australasian Journal of Animal Sciences
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• 제9권3호
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• pp.247-254
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• 1996

Three stages of growth of Italian ryegrass (pre-blooming, P-B; early-blooming, E-B; and late-blooming, L-B) were used to evaluate the effect of maturity on in vitro digestion of dry matter, fiber components and gas production. The rumen digestibility and gas production values were obtained by incubation of each sample in the rumen fluid of sheep for 12, 24, 36, 48 and 72 hr, respectively. The results showed that digestibility of dry matter (DM) significantly reduced (p < 0.05) as advancing maturity of the grass. Similarly, the digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) also significantly decreased (p < 0.05) with advancing maturity at all incubation times. However, the effect of maturity on digestibility of cellulose and hemicellulose was only detected when the samples were incubated more than 36 hr, where L-B was lower than P-B and E-B. Potential digestibility of nutrients, the maximum digestibility attainable in the rumen theoretically, was also higher at P-B than those of E-B and L-B. The amount of gas produced by microbial fermentation was closely related to the extent of DM digestion, and it was negatively correlated with advancing maturity of the grass.

• Asian-Australasian Journal of Animal Sciences
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• 제27권3호
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• pp.330-341
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• 2014

Andropogon gayanus is an important grass due to its high biomass production, drought tolerance and favorable growth on low fertility acidic soils. Currently, there is little research on the impact of growth stage on the nutritional quality or the degree of $CH_4$ production that may arise from this forage during ruminal fermentation. The objectives of this study were to determine the effects of regrowth stage of A. gayanus on its chemical composition, in vitro production of gas and CH4, as well as in vitro dry matter (DM) digestibility when grown under tropical Brazilian conditions and conserved as hay or as silage. The nutritional value of A. gayanus grass declined with increasing maturity; however digestible DM yield linearly increased. After 112 d of regrowth, A. gayanus produced higher quality silage (higher lactate and lower pH and butyrate content) and higher DM yield. However, the low levels of crude protein at this time would make protein supplementation a necessity for proper rumen fermentation. No differences in $CH_4$ kinetic parameters were found with advancing maturity or preservation method (hay or silage).

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.225-231
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• 2009

The objective of this experiment was to study the effects of grass maturity at harvest on the nutritive value of grass silage (GS) in relation to voluntary intake, digestibility, nitrogen (N) utilization and in sacco dry matter (DM) degradability. Silage was cut from a sward dominated by orchardgrass (Dactylis glomerata L.) at the late-vegetative (early-cut), internode elongation (mediumcut) and flowering (late-cut) stages of growth. The DM yield at harvest was the lowest for early-cut silage (5.4 t/ha) and increased to 6.5 and 7.0 t/ha for the medium and late-cut silage respectively. As the crop matured, the crude protein (CP) concentration decreased significantly (p<0.05) and there was a marked increase in acid detergent fiber (ADF) concentration (p<0.001). The three different silages were offered to four 18-month old Charolais wether sheep to measure the voluntary intake, in vivo digestibility and N retention over four 21-day periods in an incomplete changeover design. Silage degradability characteristics were determined using four fistulated sheep to measure DM degradability over 3, 6, 12, 24, 48 and 72 h. There was a linear decrease in the voluntary intake of silage fresh matter, DM, organic matter (OM) and neutral detergent fiber (NDF), digestibility of DM, OM, NDF, ADF and CP, and digestibility of OM in DM (Dvalue) ($P_L<0.01$) as harvesting of grass was delayed. Nitrogen intake, N output in urine, N output in faeces and N balance also linearly decreased ($P_L<0.01$) with postponed harvesting of grass for silage. DM degradability and effective degradability (ED) significantly decreased with increasing maturity of grass at harvest. The results suggest that harvesting date has a significant influence on the nutritive value of GS in terms of intake, digestibility, N balance and in sacco degradability in the rumen. It was concluded that early harvest GS ensured higher intake, digestibility, N intake and DM degradability in comparison with the medium and the late cut GS as a result of improved rumen N efficiency and utilization probably due to a better balance of available energy and protein.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.41-48
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• 1994

This experiment was carried out in order to evaluate the chemical composition and rumen degradation characteristics of Italian ryegrass harvested at three different growth stages, i,e. pre-blooming, early-blooming and late-blooming. Degradation values were obtained by incubation of the samples using the nylon bag technique on the rumen of sheep fed a normal diet (Timothy hay with 200 g/d concentrate per head) for 12, 24, 36, 48 and 72 hours, respectively. Neutral detergent fiver (NDF) content was highest at late-blooming (64.4%) while no difference was found among the pre-blooming and early-blooming (49.4% vs 48.3%). However, acid detergent fiber (ADF) content markedly increased from 30.0% at pre-blooming to 35.4% and 46.4% at early-blooming and late-blooming, respectively. Lignin and silica contents also increased as advancing maturity of the grass, Rumen degradation of dry matter (DM) significantly reduced (p < 0.05) as advancing maturity of the grass. Ruman degradation cellulose and ADF at pre-blooming were significantly higher (p < 0.05) than those of early-blooming and late-blooming. However, no significant differences were observed among the early-blooming and late-blooming. With advancing maturity, rumen degradation of NDF and hemicellulose significantly reduced (p < 0.05) at the incubation times.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1611-1611
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• 2001

The main selection parameters used by forage grass (rye and Italian rye grass) breeders are dry-matter yield, seasonal growth, persistency, disease resistance, heading date, and heading. These characteristics can all be identified usually in the segregating F2 population, however characteristics such as soluble carbohydrate level, protein, lipid and digestibility cannot be identified. The emphasis of this work is to introduce a quantitative selection process for characterization of herbage quality e.g. protein, water-soluble carbohydrates, fiber fractions, dry matter digestibility. NIRS calibrations are currently being developed for identifying grass genotypes to assist the selection process, thereby allowing the opportunity to actively breed improved herbage quality. The changes in fibre fractions, associated components and digestibility of a number of grass clones at different growth stages are being assessed changes taking place during a growing season. This will provide a database of the major changes taking place during a growing season. Attempts to classify quality differences between genotypes will be carried out using multivariate analysis of the spectral data. I addition changes associated with maturity of grass will be considered in order to develop robust calibrations.

• Journal of Animal Science and Technology
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• 제47권6호
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• pp.985-1000
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• 2005

리놀렌산(C18:3)과 리놀산(C18:2)의 biohydrogenation 과 반추위 내에서의 이들 지방산의 bypass를 검토하기 위하여 3 구로 나누어 티모시 조사료를 반추위액과 함께 in vitro상에서 39℃, 0, 3, 6, 9, 24, 36 시간 동안 혐기 배양 시험을 하였다. 첫번째 시험의 목적은 C18:2과 C18:3의 in vitro biohydrogenation에 대한 조사료의 성장 단계(stem elongation, early heading, late heading, early flowering)와 질소 시비(0 and 120kg N ha－1)의 영향을 시험하는 것이었다. 수소첨가가능분획(hydrogenable fraction), C18:2과 C18:3의 효과적인 소실과 bypass는 stem elongation 시 수확된 티모시에서 높았고, 성숙함에 따라 일정하게 감소하였다. 질소시비구는 C18:3의 수소첨가가능분획, C18:2과 C18:3의 효과적인 소실과 bypass가 증가하였다. 그러나 C18:2과 C18:3의 소실율은 성숙과 질소시비(P≻0.1)에 의해 영향을 받지 않았다. 2번째 시험에서는 in vitro C18:2과 C18:3 biohydrogenation에 대한 티모시 보존 방법의 영향을 보았다. 사일리지는 C18:2과 C18:3를 가장 효과적으로 소실시켰으며, 건초는 가장 효과가 낮았다. C18:2과 C18:3의 biohydrogenation 된 양은 건초에서 보다 헤일리지와 사일리지에서 더 높았다. 티모시 헤일리지와 비교하였을 때 C18:3의 bypass는 신선 목초, 시든풀, 건초에서 더 높았다. C18:2의 bypass는 건초와 헤일리지에 비해 신선목초와 사일리지가 더 높았다. 3번째 시험에서는 C18:2과 C18:3의 소거와 bypass에 대한 티모시 헤일리지와 사일리지에 대한 개미산 첨가와 Lactobacillus plantarum 접종의 효과를 검토하였다. 개미산의 첨가는 헤일리지와 사일리지에 있어서 C18:3의 biohydrogenation 비율을 증가시켰으나 사일리지에 있어서 C18:2의 수소첨가 가능분획을 감소시켰다. 이러한 3가지 배양구의 결과는 티모시에 있어 C18:2과 C18:3의 수소첨가 가능분획과 bypass가 성숙도에 따라 감소하였고 질소시비에 따라 증가하였음을 보여 준다. 헤일리지와 사일리지에서 건초에서 보다 C18:2과 C18:3의 더 많은 양이 biohydrogenation 되었으며 C18:3의 반추위 소실은 헤일리지에서 보다 신선목초, 시든풀, 건초에서 더 높았다.

• Asian-Australasian Journal of Animal Sciences
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• 제2권2호
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• pp.123-128
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• 1989

An experiment was conducted to study the effect of frequency of defoliation on the ensiling characteristics and nutritive value of Guineaecotype 'A' (Panicum maximum Jacq) grass. Guinea grass harvested at 2, 3, 4, 5, 6, 7, 8, 9, 10 and 12-week cutting intervals was chopped (2 cm) and ensiled alone or with the addition of coconut (Cocos nucifera L.) meal (w/w-fresh weight basis), for periods of 6, 7 or 8 weeks in 2-litre laboratory silos. Dry matter, water soluble carbohydrates, lactic acid, pH, ash, nitrogen and digestibility in vitro were measured in representative samples of preensiled and ensiled material. Dry matter content of silages prepared from herbage harvested at 2 and 3 weeks intervals was lower (P<0.05) compared to longer defoliation intervals. The pH of silage prepared from herbage over 8 weeks old were higher (P<0.05) than those harvested below 8 weeks. The water soluble carbohydrate content of silage prepared from 3-weekly defoliated herbage was higher (P<0.05) than those prepared from longer periods. Lengthened growth period decreased (P<0.001) the crude protein content of the ensiled material, whereas the addition of coconut meal resulted in marginal increases. In vitro organic matter digestibility of the silages decreased (P<0.05) with the increase in forage maturity.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.381-385
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• 2006

This study examined the influence of re-growth periods on chemical composition, biomass production, nutritive value and digestion kinetics of Setaria sphacelata (SS) and Cenchrus ciliaris (CC) in ruminally cannulated buffalo bulls. Two re-growth intervals i.e. clipping every month ($CI_1$) and clipping after every two months ($CI_2$) were compared with the control (clipped after 4 months). Mean values of leaf to stem ratio in SS and CC grasses were decreased (p<0.05) with increasing re-growth interval. The lowest leaf to stem ratio was recorded in control plots of both grasses. In both grasses, increasing growth period increased the concentrations of dry matter (DM), neutral detergent fiber (NDF) and organic matter (OM) and decreased crude protein (CP). Mean dry herbage, OM and CP yields of SS and CC were increased (p<0.05) with increasing re-growth interval. Ruminal DM and NDF digestibilities of SS and CC were decreased (p<0.05) with increasing interval. Ruminal rate of DM and NDF disappearance was higher while the ruminal lag time of these nutrients was lower with monthly than with bi-monthly clipping interval. The results from present study imply that SS and CC clipped after every two months is more beneficial than when clipped every month or every four months in terms of optimal biomass with adequate nutritional value for buffaloes.

• 한국작물학회지
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• 제32권4호
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• pp.455-461
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• 1987

Festuca속의 토올페스큐와 메도우페스큐, 그리고 Lolium속의 이탈리안라이그라스들 간에 종속간 잡종을 얻기 위하여 기내수분과 기내배양을 실시하였다. 이들 작물들의 자방과 화분을 채취하여 소독을 하고 주두수분, 주두제거 수분, 배주수분의 3가지 방법으로 기내수분을 실시하였다. 그리고 이들의 배발육상태를 MS, N6 , White's의 배지종류와 IAA Kinetln, BA의 생장조절물질의 처리로서 비교하였다. 1. 토올페스큐, 메도우페스큐, 이탈리안라이그라스의 상호 조합간 기내수분에서 44~92%의 수정율을 나타내었다. 이들의 주두수분은 평균 67.8% 주두제거 수분은 평균 89%의 수정율을 보였으나 배주수분은 평균 61 %로 낮았다. 2. 화본과 수정배주에서 배발육을 촉진하는데는 White's 배지가 가장 효율적이었고 식물생장조절물질의 처리는 IAA(10mg/$\ell$)와 Kinetin(0.2 mg/$\ell$)의 혼합처리가 무처리보다 효과적이었으나 발아율은 극히 저조하였다 3. 기내배양으로 성숙 배주의 배부조직에서 유관책의 형성과 시원체조직의 분화를 확인할 수 있었으며 배주 내부에 후막세포들의 형성이 관찰되었다.

• 한국초지조사료학회지
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• 제29권4호
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• pp.375-382
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• 2009

본 시험을 수행하기 위해서 6개월령 거세한 우 64두를 공시하여 주구는 조사료원으로 목건초와 볏짚 처리구를 배치하였으며, 세구는 출하시기로 24개월, 26개월, 28개월 및 30개월 배치하였다. 본 시험은 조사료원 및 출하시기별 발육 및 육질에 미치는 영향을 구명하기 위하여 수행하였다. 발육 및 사료이용성은 목건초 급여구가 볏짚 급여구에 비하여 동일 출하월령에서 10~12% 정도 더 발육이 향상되었으며(p<0.05), 배합사료 요구량에서도 목건초 급여 구가 볏짚 급여구에 비하여 kg 증체당이 향상 되는 결과를 얻었다. 또한 도체등급에서도 등 지방두께 및 배최장근단면적은 출하월령이 증가할수록 증가하였으며, 근내지방도 역시 출하월령이 증가할수록 증가하는 경향을 보였다. 따라서 한우 고급육을 생산하기 위해서는 볏짚 보다는 목건초 급여로 출하시기를 28개월령 이상 사육하는 것이 바람직한 것으로 사료된다.