• Asian-Australasian Journal of Animal Sciences
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• 제26권5호
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• pp.711-715
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• 2013

To investigate the effect of restricted grazing time on behavior of Tan sheep on desert steppe, forty 4-months old male Tan sheep with an original body weight (BW) of $15.62{\pm}0.33$ kg were randomly allocated to 4 grazing groups which corresponded to 4 different restricted grazing time treatments of 2 h/d (G2), 4 h/d (G4), 8 h/d (G8) and 12 h/d (G12) access to pasture. The restricted grazing times had a significant impact on intake time, resting time, ruminating time, bite rate and movement. As the grazing time decreased, the proportion of time spent on intake, bite rate and grazing velocity significantly (p<0.05) increased, but resting and ruminating time clearly (p<0.05) decreased. The grazing months mainly depicted effect on intake time and grazing velocity. In conclusion, by varying their foraging behavior, Tan sheep could improve grazing efficiency to adapt well to the time-limited grazing circumstance.

• 한국초지조사료학회지
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• 제9권2호
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• pp.88-95
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• 1989

This experiment 'was conducted to investigate the grazing cattle's palatability by the method of grazing time on the pasture dominated orchardgrass and on the pasture dominated perennial ryegrass from June to October, 1987. The experiment was carried out on the experimental field at Livestock Ex- Experiment Station. The results are summarized as follows: 1. In summer, the grazing time on the pasture dominated orchardgrass increased in 49.7 min, 57.4 min, 102 min, 118.7 min, respectively as sward height decreased in 50 cm, 45 cm, 35 cm, 23 cm, respectively and their correlation coefficiet was -0.9722*(P <0.05). 2. In autumn, the grazing time on the pasture dominated perennial ryegrass decreased in 182 min, 98.5 min, 49.4 min, 31.9 min, respectively as sward height decreased in 43 cm, 34 cm, 25 cm, 18 cm, respectively and their correlation coefficient was 0.9684*. (P <0.05). 3. Grazing time increased as sward height increased on the pasture dominated perennial ryegrass because the composition rate of orchardgrass and red clover which were palatability on the plot of the high sward height.was many. It was suggested that the factor that could be first related to palatability on mixture pasture was the factor of species than the factor of sward height. 4. When the eating rate on the plot of the low sward height was over 55% as the grazing day went by, it gradually decreased because the eating rate on it was high but the fresh yield was low. After all it seemed that it affected palatability because forage availability on the plot of the low sward height was degenerating.

• Asian-Australasian Journal of Animal Sciences
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• 제15권10호
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• pp.1453-1457
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• 2002

The experiment was conducted to find out the effect of 4 feeding systems on growth, feed intake, eating behavior, lactation performance, gestation period, post-partum heat period, conception rate and parasitic infestation of Black Bengal goat. Twenty four does of approximately 1 year of age were randomly selected for 4 treatment (feeding systems) groups having 6 replications in each. Treatments were stall feeding ($T_1$), tethering ($T_2$), restricted grazing ($T_3$) and grazing ($T_4$). $T_1$ group was housed continuously and adequate amounts of natural grass were supplied for ad libitum feeding. $T_2$ group was tethered for grazing natural grass from 8 a.m. to 4 p.m. being moved at one hour intervals. Goats of $T_3$ group were allowed grazing from 8 a.m. to 1 p.m. $T_4$ group was grazed from 8 a. m. to 4 p.m. Concentrate supplement was given at the rate of 150 g per day per goat for all of the treatment groups. Duration of experiment was 219 days. Daily live weight gain was significantly (p<0.05) higher in case of stall fed goats than that of others. DM intake also significantly (p<0.05) differed among the treatment groups and was 3.40 3.95, 3.76 and 4.05 per cent of their live weight for stall feeding, tethering, restricted grazing and grazing groups, respectively. Rate of rumination was significantly (p<0.05) higher in case of tethering group of goats than that of others. Birth weight of kids, milk yield, lactation period and post-partum heat period were significantly higher in case of stall fed goats than others. Tethering group showed significantly (p<0.05) higher litter size than others. Infestation rate of Fasciola was significantly (p<0.05) higher in the grazing group. In conclusion, it may be stated that among these feeding groups overall performance of stall fed goats was more satisfactory, and that the tethering group showed better performance than the others.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.514-520
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• 2006

An abandoned mandarin orange orchard in southwestern Japan was set-stocked by Japanese Black cows at two stocking rates (1.0 and 2.0 animals/ha), and vegetation dynamics and diet selection by cattle were monitored for two years, in an effort to obtain information on effective use of abandoned agricultural fields for low-cost animal production and environmental conservation. Two dominant species at the commencement of grazing, kudzu (Pueraria lobata Ohwi) and tall goldenrod (Solidago altissima L.), showed different responses to grazing during the two years; the composition of kudzu decreased, contrasting with that of tall goldenrod which increased at both stocking rates. This was caused by high preference for kudzu and avoidance or low preference for tall goldenrod by cattle. Retrogression of vegetation due to cattle disturbances occurred at both stocking rates, with the high stocking rate leading to a lower degree of succession than the low stocking rate. It was shown that cattle grazing, particularly at a high stocking rate, was effective in the management of vegetation of an abandoned orchard.

• 한국초지조사료학회지
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• 제20권3호
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• pp.161-168
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• 2000

The experiment was carried out to investigate the effect of extension of grazing duration in late autumn on grass growth in following spring, in order to improve the rate of self-sufficiency for roughage feed. Plant height, total biomass and litter production of herbage were increased when the grazing was finished early in late autumn. The proportions of clover and litter, and amounts of animal intake were decreased, with extended grazing duration in late autumn. But when the grazing was finished late in autumn, the contents of crude protein (CP, %) of herbage were increased, contents of acid detergent fiber (ADF, %), neutral detergent fiber (NDF, %) and crude ash (%) were decreased in pasture after grazing, therefore the contents of total digestible nutrients (TDN, %) and relative feed value (RFV) of herbage were improved. The early end grazing showed that plant height, total biomass and litter production of herbage in following spring were higher than those in late end grazing. However, increased yields were not significantly different among end grazing treatments (0.12-0.15 tonha), except for the final end grazing in late autumn (0.01 tonha). With extended grazing duration in late autumn, the contents of CP of herbage in following spring were increased, contents of ADF, were decreased, and RFV were improved. (Key words : Extension of grazing duration, Plant height, Biomass, Amount of intake, Increased yield, Crude protein, TDN) rll\ulcorner c# qiil x i 9 ~ 1 a% * (College of Natural Resources, Taegu Univ., Kyongsan, 71 2-714, Korea) * $4 4 qiil 34 qq(Co1lege of Liberal Arts & Sciences, Yonsei Univ., Wonju, 220-701, Korea) '* 8 * jL@%ft@ &@%(Faculty of Agriculture, Hokkaido Univ., Sapporo, 060 Japan)

• The Korean Journal of Ecology
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• 제22권6호
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• pp.337-342
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• 1999

Rotifer grazing rates in both species and community levels on bacteria and phytoplankton were determined by using representative models (fluorescent beads: 0.75$\mu m$ for bacteria and 10 $\mu m$ for phytoplankton) at biweekly intervals. One-year study at the lower part of the Nakdong River (Mulgum) indicated that the seasonal pattern of rotifer biomass was similar to that of total zooplankton biomass. Total mean biomass of rotifers was significantly higher than that of other groups (rotifers, 148$\pm $327 $\mu g$C/l; cladoceran. 25$\pm 69$$\mu g$C/l; copepodids. 58$\pm 159$$\mu g$C/l). For laboratory grazing experiments. mean specific filtering rate (SFR: $ml\cdot \; l^{-1}\cdot \; day^{-1}$) for rotifers varied from 0.001 to 0.726, and > 90% individuals of rotifer species took up fluorescent microspheres. The high SFRs were achieved by Brachionus angularis, B. calyciflorus, and Filinia longiseta. Community filtering rates (CFRs, $ml\cdot \; l^{-1}\cdot \; day^{-1}$) varied in the range from 2 ~ 1,670. Rotifer filtering rates on phytoplankton were much higher than bacterial filtering rates, especially in the late growing season (May. June, and November). Rotifers appear to be important in transferring both bacterial and phytoplankton carbon to higher trophic levels at the lower Nakdong River.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제13권12호
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• pp.1779-1787
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• 2000

Southern and south-western Australia is a typical mediterranean environment, characterised by wet, cold winters and dry, hot summers. The evaporation rate varies significantly in summer, resulting in a high salinity of drinking water for grazing animals. In addition, a large amount of land in the cropping areas is affected by salt. Puccinellia, tall wheat grass and saltbushes have been planted to improve the soil condition and to supply feed for grazing animals. Animals grazing these areas often ingest an excessive amount of salt from soil, forage and drinking water which can reduce feed intake, increase the water requirement, depress growth and affect body composition as demonstrated in sheep. While the deer industry has been successfully developed in these regions, the potential impact of excessive salt intake on deer production is unknown. The salt tolerance has been well defined for sheep, cattle and other livestock species, but the variation between animal species, breeds within species, maturity status and grazing environments makes it impossible to apply these values directly to deer. To optimise deer production and effectively use natural resources, it is essential to understand the salt status of grazing deer and the impact of excessive salt intake on growth and reproduction of deer.

• 한국해양학회지
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• 제30권5호
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• pp.426-435
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• 1995

탄소순환에서 섬모충류에 의한 직접적인 박테리아 섭식의 중요성을 알아보기 위하 여 만경 동진강 염하구에서 1993년 10월부터 1995년 3월까지 4회에 걸쳐 섬모충류의 수도(abundance)와 생물량 그리고 40um 이하의 작은 섬모충류의 박테리아 섭식률을 조 사하였다. 40 um이하의 작은 크기 섬모충류 수도는 전체 섬모충류 수도의 평균49.5%이 상을 차지하였다. 이러한 작은 크기 섬모충류의 박테리아 섭식률은 시간당 18.0106.3 nl cell/SUP -1/로 박테리아의 수도가 증가할수록 여과율은 감소하는 반면, 섭식률은 증가하는 경향을 보여 박테리아의 농도가 섭식률에 영향을 미치는 것으로 보인다. 섬 모충류의 섭식이 박테리아 생산력중 차지하는 비율은 0.1-12.2%로 박테리아 수도가 증 가함에 따라 박테리아 생산력중 섬모충류에 섭식되는 비가 지수적으로 증가하는 경향 ($r^2$=0.62,p$\leq$0.001)을 보였다. 즉, 섬모충류의 섭식이 박테리아에 미치는 영향을 전 형적인 연안에서는 작으나 박테리아의 농도가 높은 부영양화 지역에서는 더 클 것으로 추측된다. 탄소순환에서 작은 섬모충류가 박테리아를 섭식하여 얻는 탄소량은 섬모충 류가 최대생산력 을 나타낼 때 필요탄소량의 평균3.1%에 불과하여 미소순환고리에서 섬모충류는 박테리아의 직접적인 섭식자보다는 최종적인 섭식자로서의 역할이 큰 것으 로 생각된다.

• 한국초지조사료학회지
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• 제35권1호
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• pp.1-5
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• 2015

본 연구는 흑염소 사양체계 확립에 대한 기초자료를 얻고자 방목과 사사형태의 사육이 흑염소의 번식능력과 자축의 발육성적에 미치는 영향을 조사하였다. 공시축은 흑염소 36두를 방목구와 사사구로 나누어 처리구당 18두씩 공시하여 2011년 4월부터 11월까지 8개월간 수행하였다. 단태의 비율은 방목구가 31.5%, 사사구가 37.0%로 통계적인 차이는 나타나지 않았다. 산자수는 방목구와 사사구가 각각 1.76과 1.69두로 사육형태에 따른 차이가 나타나지 않았으며, 이유 시의 두수는 방목구가 사사구 보다 높은 경향으로 나타났다(p=0.11). 사육형태에 따른 생시체중은 방목구가 2.3 kg, 사사구가 2.29 kg 로 나타나 차이가 나타나지 않았으나, 생후 90일 령 이유 시 방목구가 9.97 kg 로 사사구의 9.45 kg 보다 높은 경향으로 나타났으며(p=0.09), 포유기간 일당증체량에서도 방목구가 사사구 보다 높은 경향으로 나타났다(p=0.13). 이상의 결과를 종합해 보면, 흑염소를 방목과 사사형태로 사육하였을 때, 분만형태, 산자수 및 생시체중에는 차이가 없었으나, 이유두수 및 자축의 일당증체량에서는 방목사육 형태가 우수한 경향으로 나타나, 방목이 흑염소의 생리적 욕구를 충족시켜 건강한 흑염소 생산에 기여 할 것으로 판단된다.