• The Korean Journal of Applied Statistics
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• v.27 no.7
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• pp.1187-1196
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• 2014

Italian Ryegrass (IRG), which is known as high yielding and the highest quality winter annual forage crop, is grown in mid-south area in Korea. This study aims to analyze the cause-and-effect relationship between IRG yield and climate variables such as temperature and precipitation by using IRG data and climate data of Korea Weather Bureau. From path analysis of structural equation model under multivariate normality, we found that there was a weather effect on IRG yield that the winter grass IRG yield was directly affected by spring temperature and indirectly affected by spring rainfall. These results showed that IRG can be sown in early spring in the area where it is hard to prepare for winter due to low temperature. This paper can contribute to increase IRG yield by showing the cause-and-effect relationship and this study can be extended to various structural equation models for other crops.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.30-37
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• 2016

Microalgae are functional foods because they contain special anti-aging inhibitors and other functional components, such as ecosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and omega-3 polyunsaturated fatty acids. Many of these functional dietary components are absent in animals and terrestrial plants. Thus, microalgae are widely utilized in human functional foods and in the feed provided to farmed fish and terrestrial livestock. Many marine organisms consume microalgae, often because they are in an appropriate portion of the cell size spectrum, but also because of their nutritional content. The nutritional requirements of marine organisms differ from those of terrestrial animals. After hatching, marine animals need small live forage species that have high omega-3 polyunsaturated fatty acid contents, including EPA and DHA. Euglena cells have both plant and animal characteristics; they are motile, elliptical in shape, 15-500 μm in diameter, and have a valuable nutritional content. Mixotrophic cell cultivation provided the best growth rates and nutritional content. Diverse carbon (fructose, lactose, glucose, maltose and sucrose) and nitrogen (tryptone, peptone, yeast extract, urea and sodium glutamate) supported the growth of microalgae with high lipid contents. We found that the best carbon and nitrogen sources for the production of high quality Euglena cells were glucose (10 g L^–1) and sodium glutamate (1.0 g L^–1), respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.516-521
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• 2002

The objective of this study was to compare two varieties of Napier grass (Bana Napier grass vs French Cameroon Napier grass) and to determine whether feed intake, digestibility, average daily gain (ADG) and milk yield of lactating Friesian cows from fresh cut Bana Napier grass was greater than from French Cameroon Napier grass, using a completely randomized design. Results show that Bana Napier grass had similar percent dry matter (DM), ash and gross energy (GE) to French Cameroon. Bana grass had higher percent crude protein (CP) and lower fiber fractions, acid detergent fibre (ADF), neutral detergent fibre (NDF) and lignin compared to French Cameroon. Overall the forage quality was marginally higher in Bana Napier grass compared to French Cameroon. The DM and NDF intake expressed as a percentage of body weight (BW) were similar in both Napier grass types. Both grasses had similar digestible DM and energy. Bana had higher digestible CP but lower digestible ADF and NDF than French Cameroon. Bana Napier was not different from French Cameroon when fed as a sole diet to lactating cows in terms of low DM intake, milk yield and a loss of BW and condition. To improve the efficient utilization of both Napier grass varieties, a supplement capable of supplying 1085-1227 g CP/d and 17.0-18.0 Mcal ME/d is required for cows to support moderate gains 0.22 kg/d and 15 kg 4% fat corrected milk/d.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1075-1079
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• 1999

Adult German cross $(German{\times}British{\times}Russian)$ angora rabbits (one year age), 32 in number were divided randomly into four groups $(T_1-T_4)$ with equal sex ratio and fed diets containing $T_1$ groundnut cake (GNC); $T_3$, soyaflakes (SF); $T_4$, sunflower cake (SFC) and $T_2$, a mixture of all the three cakes along with green forage as roughage for a period of 9 months. Nine per cent protein was added from each protein source. Fibre level was maintained by adjusting the level of rice phak in the diets. The diets were iso-nitrogenous and contained similar level of fibre. DMI through roughage was not affected due to source of protein in the diet, however, DMI through concentrate was higher $(p{\leq}0.05)$ with SFC diet, which resulted in higher total feed intake in the group $(T_4)$. Body weights increased up to second shearing, thereafter it decreased due to summer depression. Diet containing soyaflakes sustained higher wool yield whereas, it was lowest $(p{\leq}0.05)$ on SFC diet. Wool attributes (staple length, medullation, fibre diameter) were not affected due to source of protein in the diet. Digestibility of fibre and its fractions (ADF, cellulose, hemicellulose) decreased $(p{\leq}0.05)$ with incorporation of SFC in the diets. Balance of calcium was lowest whereas, that of nitrogen was highest with SFC diet $(T_4)$. Biological value of N and net protein utilization was better when different protein sources were mixed together $(T_2)$. Protein quality of soyaflakes proved better for wool production followed by groundnut cake and mixture of three protein sources. Sunflower cake alone or in combination decreased wool production which may be checked by supplementation of amino acids and energy.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.978-983
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• 2006

Forages from grazing lands comprise conventional feed resources for ruminants in the tropical region. A study was conducted to assess fodder productivity and nutritive potential of deferred forages of six silvopastoral traditional fodder banks in central northwest Tanzania, traditionally known as Ngitiri. The grazing lands were dominated by low quality increaser grass species: Eragrostis spp., Aristida spp., Urochloa spp., Rottboellia exaltata, Cenchrus spp., Cynodon spp. and Chloris spp., and forbs species. The grazing lands had low vegetative basal cover that varied (p<0.05) from 34.7 to 75%, and low forage biomass productivity that varied (p<0.05) from 0.76 to 3.69 tones (t) dry matter (DM)/ha. The forages contained low crude protein (CP) that varied (p<0.05) from 16 to 27 g/kg DM; and had high fibre contents, which varied (p<0.05) from 702-725, 497-573 and 119-225 g/kg DM for neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL), respectively. The forages were poorly degraded in sacco, and showed low DM degradability (DMD) characteristics of 74, 473 and 576 g/kg DM for DM washing losses (a), slowly degradable feed fraction (b) and potential degradability, (a+b), respectively; and low DMD at 48 h incubation, which varied from 317-345 g/kg DM, and contained low metabolizable energy (ME), (4.2-4.36 MJ/kg DM). The herbage forages would not meet protein and energy requirements for maintenance and production, which could be reflected through low animal productivity. Further work is needed to assess animal productivity (growth, milk, draft force) from conserved forages in traditional fodder banks in the dry season.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1657-1662
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• 2004

The forage potential of mulberry (Morus alba) was evaluated under Malaysian conditions. The yield and nutrient composition of plant fractions of mulberry (whole plant, leaf and stem fractions) were determined at four harvest stages, namely, 3 (W3), 5 (W5), 7 (W7) and 9 (W9) weeks in a randomized block design. The study was conducted over a 9-month period to assess the persistence of the crop to repeated harvests. Fresh and dry matter (DM) yields of all plant fractions increased significantly (p<0.01) with increasing intervals between harvests, with highest DM yields at W9. The leaf to stem ratio declined significantly (p<0.01) from 5.2 (W3) to 0.9 (W9), indicating predominance of the stem fraction with advancing maturity. The nutritional composition of plant fractions was also significantly influenced (p<0.01) by advancing plant maturity at harvest. Crude protein (CP), ash and the metabolisable energy content of plant fractions declined significantly (p<0.01) from W3 to W9, while there was a corresponding significant increase (p<0.01) in the acid detergent fibre, neutral detergent fibre and acid detergent lignin. From this study it was concluded that the optimum stage to harvest the whole plant is 5 weeks, which is a compromise between yield, nutrient composition (CP and fibre components), and the annual number of cuts, with good crop persistence to repeated harvests. Fresh mulberry whole plant can provide a valuable supplemental source of nutrients to poor quality basal diets.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.325-333
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• 1994

This study was undertaken at Gowa, South Sulawesi, Indonesia as part of a larger forage genetic resource evaluation project. The experimental program consisted of a field experiment where grasses and legume species were grown in monocultures and the yield, N content and rumen bag digestibility using goats were measured. The field experiment was conducted from December 1985 to October 1986. Eight species of legumes (Desmodium heterophyllum cv. John-stone, Desmodium triflorum from Gowa, South Sulawesi, Arachis sp. from Maiwa, South Sulawesi, Clitoria ternalea CPI 50973, Macroptilium atropurpureum ev. Siratro, Neonotonia wightii cv. Tinaroo, Centrosema pubescens CPI 58575, Centrosema plumeri CPI 58568) were grown as monocultures. After establishment all plants were cut to a uniform height of 5 cm, and subsequent cuts were made on regrowth after 14, 28, 42, and 56 days (cycle 1). Cycle 2 commenced towards the end of the wet season and continued for 157 days into the dry season. The highest yielding legumes were C. ternatea in the wet season and Arachis sp. in the dry season. The mean rumen bag dry matter digestibility (RBDMD) of legumes of 67.6% for leaf material (averaged over all cycles and ages) was 7.6% higher than for stem material. The RBDMD of Arachis was significantly higher than all other species. The RBDMD of all legumes declined with age. Calculation of yield of digestible DM (yield $\times$ RBDMD) showed that Arachis sp. was the best legume. The combination of plant "quality" with yield measures is a valuable adjunct to routine agronomic survey procedures in plant evaluation programs. Arachis sp. appears to offer considerable promise and should be more widely evaluated.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1516-1519
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• 2001

The data consisted of 369 lactation records for calvings over a sixteen-year period (1972-1987) and included only cows that had normal milk records. The data were analysed using a linear model containing the fixed effects of parity, year of calving and season of calving. The least squares means${\pm}$S.E. were $1,273{\pm}58.4kg$ for milk yield, and for post-partum body weight (kg) at 2, 3 and 4 months after calving were $343.40{\pm}3.96$, $346.10{\pm}4.10$ and $352.54{\pm}4.26$, respectively. With the exception of season of calving, the effects of parity and year of calving were significant (p<0.01) on the performance of the animals. Thus, the mean-milk yields 1162, 1351 and 1350, were similar for pre-, peak- and post rainy seasons, respectively. On the other hand, as parity increased from 1 to 3, milk yield also increased, but thereafter, there was a gradual decline in milk yield. Similarly, post-partum body weight also increased with parity. However, no consistent pattern for year effect was observed which probably was a reflection of the variation in climatic conditions, or forage quality and/or availability. The phenotypic correlations between milk yield and post-partum body weights were negative and small (ranging from -0.01 to -0.08). However, high milk production in cows was associated with longer calving interval. The implications from the phenotypic correlations are suggestive of one or two possibilities. Firstly, selection for increased body weight may actually result in decreased milk yield. Also, a substantial genetic antagonism may exist between milk yield and fertility in the crossbred cows. Therefore, it is important that selection to improve milk production should take into consideration the reproductive performance of the cows.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.196-200
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• 1993

A full understanding of the interdependence of leaf nitrate (($No_3$￣) metabolism and symbiotic nitrogen($N_2$) fixation in legume crops is needed to help maximize the use of both N sources as well as to improve forage quality through the inhibition of leaf nitrate accumulation. The present work examines the effects of added nitrate, the level of which are 0,2,4,8 and 12mM, on the nodule formation and leaf nitrate utilization and on the possibility of inducing nitrate-toxicity to livestocks in two alfalfa varieties, ' Vernal ' of grazing type and ' Victoria ' of hay type. Higher level of exogeneous nitrate resulted in the increased above-ground dry weight. Nodulation was inhibited severely when more than 8mM NO$_3$￣ was supplied to alfalfa plants, and leaf nitrate reductase reached a maximunm at 4mM nitrate supply. The $V_{max}$of nitrate reductase in leaves of Vernal was similar to that of Victoria, whereas the $K_m$ of Vernal was higher than that of Victoria. High accumulation of leaf nitrate, $4{\times}10^{-5}$ g/g leaf fresh weight, was shown at 12mM nitrate supply, which was thought to be not enough to induce nitrate-toxicity to livestocks.icity to livestocks.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.303-309
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• 2004

Conjugated linoleic acid (CLA) is currently under intensive investigation due to its health benefits. A great deal of interest has been paid to the possible health-promoting roles of CLA, but there are not many studies available on the mechanism of CLA production by ruminal microorganisms. CLA is produced as an intermediate of the characteristic biohydrogenation process of linoleic acid(LA) in the rumen and its production has direct relationship to numerous environmental factors including particle association, substrate concentration, forage-to-grain ratio, pH, ionopore, bacterial cell density, etc. Some of these factors were known to affect hydrogenating activities of Butyrivibrio fibrisolvens A38 which is an active rumen bacterium in CLA production. Dairy cow is a main source of CLA, and its level could be increased by dietary manipulation changing the physiological environment of rumen bacteria such as B. fibrisolvens A38. Therefore, the effects of various factors on. ruminal biohydrogenation should be carefully considered to optimize not only CLA production, but also other fatty acid metabolism, both of which are directly affecting nutritional quality and functionality of dairy products. In this review, the relationship between various environmental factors and ruminal CLA production is discussed focusing on the CLA production of B. fibrisolvens A38.