• 한국수산과학회지
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• 제26권2호
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• pp.173-181
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• 1993

아산만에서 영양염 및 입자성 유기물의 계절적 변화를 조사하였다. 영양염은 8월에 높고 2월에 낮았으며 무기 질소와 인산 인의 원자비는 5월의 24.8을 제외 하고는 Redfield ratio와 유사하였다. 5월에 인산 인을 제외한 다른 영양염들은 염분이 $31.5{\sim}32.0\%0$까지는 염분이 증가할수록 감소하였으나 그 후 다시 증가하여 하구 내에서 영양염 공급이 있음을 시사해주고 있다. 그러나 8월의 조사에서 영양염과 염분이 좋은 역상관 관계는 이 시기에 영양염 공급원이 담수 유입으로 추정된다. chlorophyll a 농도는 5월에 최대이었고 조사시기 동안 Rb/Ra(Rb: fluorescence before acidification, Ra: fluorescence after acidification) 비가 비교적 낮아 조사해역의 식물플랑크톤이 생리적으로 성장하기에 나쁜 환경에 있는 것으로 사료된다. 입자성 유기 규소(PBSi)와 입자성 유기탄소(POC)의 비가 낮고 PBSi/chlorophyll a 비 및 POC/chlorophyll a 비가 상대적으로 높아 아산만에서 저층으로부터 많은 non-living detritus의 공급이 있는 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.181-188
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• 2006

The objective of this research was to determine the effects of synchronizing the rate of dietary energy and nitrogen release on: ruminal fermentation, microbial protein synthesis, blood urea nitrogen, and nutrient digestibility in beef cattle. Four, two-and-a-half year old Brahman-Thai native crossbred steers were selected for the project. Each steer was fitted with a rumen cannula and proximal duodenal cannula. The steers were then randomly assigned in a $4{\times}4$ Latin square design to receive four dietary treatments. Prior to formulation of the dietary treatments, feed ingredients were analyzed for chemical composition and a nylon bag technique was used to analyze the treatments various ingredients for degradability. The treatments were organized in four levels of a synchrony index (0.39, 0.50, 0.62 and 0.74). The results showed that dry matter digestibility trend to be increased (p<0.06), organic matter and acid detergent fiber digestibility increased linearly (p<0.05), while crude protein and neutral detergent fiber digestibility were not significantly different (p>0.05). Higher concentration and fluctuation of ruminal ammonia and blood urea were observed in the animal that received the lower synchrony index diets. As the levels of the synchrony index increased, the concentrations of ruminal ammonia nitrogen and blood urea nitrogen, at the 4 h post feeding, decreased linearly (p<0.05). Total volatile fatty acid and bacteria populations at the 4 h post feeding increased linearly (p<0.05). Microbial protein synthesis trend to be increase (p<0.08). The results of this research indicate that synchronizing the rate of degradation of dietary energy and nitrogen release improves ruminal fermentation, microbial protein synthesis and feed utilization.

• 한국가금학회지
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• 제47권3호
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• pp.153-158
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• 2020

The effects of palm oil and soy oil supplementation in broiler chickens on growth performance and nutrient digestibility of dry matter, nitrogen, and energy was evaluated. In this experiment, 702 one-day-old Ross 308 cross bred chicks with an initial body weight of 42.23±0.05 g (mean±SD) were utilized in a completely randomized treatment design (13 replicates/treatment, 18 chickens/cage) and fed for 35 days with CON (basal diet), T1 (Basal diet + 1.3 % palm oil), and T2 (Basal diet + 1.3% soy oil). From days 1 to 7, the body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) were not significantly affected by the supplementation with palm oil or soy oil. However, from days 7 to 21, BWG showed a tendency to increase compared to that with the control treatment. Moreover, BWG was significantly improved (P<0.05) with palm and soy oil supplementation during the overall experiment in comparison to that with the control diet. In addition, the palm oil-supplemented group had higher BWG than the soy oil treatment group (P<0.05). During the overall experiment, FI tended to increase in the T1 group compared to that in the other groups. There was no significant effect on FCR and nutrient digestibility of dry matter, nitrogen, and energy during the overall trial with the supplementation of palm or soy oil. In summary, the inclusion of dietary palm and soy oil has a beneficial effect on the growth performance of broiler chickens.

• 한국초지조사료학회지
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• 제12권3호
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• pp.185-192
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• 1992

This experiment was conducted to compare the productivity of five silage corn varieties. Corn varieties were Pioneer 3144(P 3144), 3160(P 3160), 3282(P 3282), 3352(P 3352) and Suweon 19(S 19) and were seeded on May 2 and harvested on August 15. Ratios of stalk, leaf and ear, chemical composition and yields of nutrients were investigated in respective corn part. Experimental design was accepted by Latin square arrangement with five replicates and each plot had twenty two plants. The results obtained were as follows: 1. Crude portein, crude ash and nitrogen free extract(NFE) contents of whole plant ranged from 6.32 to 7.18%, 5.16 to 7.43% and 52.62 to 57.90%, respectively, and there were no significant(P>.Ol) differences between varieties. Crude protein and NFE content were the highest in ear between corn parts. 2. Crude fiber conent of whole plant ranged from 18.98 % to 24.01 %, and was the highest in suweon 19 and the lowest in P 3352(P<.01). Crude fiber content was the highest in stem and the lowest in ear, However, crude fat content(2.03-3.66 %) vice versa. 3. Yields of organic matter, crude protein, crude fat, NFE and TDN per 10a were the greatest(P< .01) in P 3282, however crude fiber yield was the highest(P<.Ol) in P 3352. 4. Ratios of different part to total dry matter yield ranged from 12.7 %(P 3352) to 17.8 %(P 3160) for leaf, 44.5(P 3352) to 66.9 %(P 3160) for stem and husks, and 16.9 %(P 3282) to 42.8 %(P 3352) for ear, and there were significant differences between corn varieties(P<.Ol). Consequently, P 3352 has the greatest nutrient yields, particularly by ear, and P 3282 has a great nutrient yield by stem. This result suggested that could be appear a better character of silage corn by hybridization of this two corn varieties.

• 한국토양비료학회지
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• 제46권2호
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• pp.129-135
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• 2013

This study was conducted to investigate the soil characteristics of newly reclaimed tidal land and the effect of green manure crops on soil properties. Summer green manure crops such as sesbania (Sesbania grandiflora), barnyard grass (Echinochloa spp.) and sorghum${\times}$sudangrass hybrid (Sorghum bicolor L.) were cultivated at Hwaong, Ewon, Saemangeum and Yongsangang area. Soil pH of reclaimed tidal land was relatively high, but organic matter and available phosphorus contents were lower compared to the optimum range for common upland crops. Soil nutrient contents were unbalanced for upland crop growth. Yield of green manure crops had a wide spatial variation. Nitrogen content in green manure crops was the greater in Sesbania and it was estimated that major nutrient ($N-P_2O_5-K_2O$) supply amount were 150-40-370, 220-50-170 and 140-50-250 $kg\;ha^{-1}$ from sorghum${\times}$sudangrass hybrid, sesbania and barnyard grass, respectively. Based on these results, desalination is required to grow the upland crops at newly reclaimed tidal lands and management practices are necessary to reduce the salt damage by resalinization during the growing seasons. To improve the productivity and increase the nutrient utilization rate, soil physicochemical properties need to be improved to the level for upland crops by application of organic matter and fertilizer.

• 농업과학연구
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• 제46권1호
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• pp.125-135
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• 2019

Late-maturing Dark Horse, and early-maturing High Speed oat varieties were seeded on March 3, 2016 and harvested on three periods: May 31, June 10, and June 20 coded as early, mid, and late-harvest, respectively. Dried and ground samples were subjected to chemical analysis to determine nutritional values such as crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), organic matter (OM), and total digestible nutrient (TDN). Effective degradability (ED) of nutrients and fermentation characteristics including volatile fatty acid (VFA) composition, pH, gas production, and ammonia-N concentration were evaluated through an in vitro digestion method. Varieties of oat hays showed significant difference in terms of nutritional value, ED, and fermentation characteristics. Dark Horse showed higher CP and OM, and lower EE contents than High Speed. Dark Horse also showed higher EDDM (dry matter), NDF, ADF, and OM than High Speed, and although High Speed showed higher pH and ammonia-N, it had lower gas and total VFA production than Dark Horse. However, in terms of harvest period, significant difference was only observed in Dark Horse where early-harvest increased the CP, and late-harvest increased the NDF and OM contents. In addition, early-harvest of Dark Horse increased the EDDM and EDNDF of the forage. Therefore, early-harvest of late-maturing Dark Horse would give better nutrient efficiency than High Speed. Allowing Dark Horse to advance in maturity would decrease its nutrient productivity and efficiency.

• Animal Bioscience
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• 제35권4호
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• pp.577-586
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• 2022

Objective: The objective of this study was to evaluate the effects of supplementing quercetin extracted from Sophora japonica flower (QS) to the diet of broiler chicks on their growth performance, apparent nutrient digestibility, cecal microbiota, serum lipid profiles, relative organ weight, and breast muscle quality. Methods: A total of 1,088 1-day-old broiler chicks (mixed sex) were randomly assigned to four groups based on the initial body weight (43.00±0.29 g). The experimental period was 35 days (starter, days 0 to 7; grower, days 7 to 21; finisher, days 21 to 35). There were 17 replicate cages per treatment and 16 birds per cage. Dietary treatments consisted of birds receiving basal diet without quercetin as the control group and treatment groups consisted of birds fed basal diet supplemented with 0.2, 0.4, or 0.6 g/kg QS. Results: With the increase of the QS dosage, body weight gain during days 0 to 7 (p = 0.021), 7 to 21 (p = 0.010), and 1 to 35 (p = 0.045), feed intake during days 0 to 7 (p = 0.037) and 1 to 35 (p = 0.025), apparent dry matter digestibility (p = 0.008), apparent energy retention (p = 0.004), cecal lactic acid bacteria counts (p = 0.023), the relative weight of breast muscle (p = 0.014), pH value from breast muscle (p<0.001), and the water holding capacity of breast muscle (p = 0.012) increased linearly, whereas the drip loss from breast muscle (p = 0.001) decreased linearly. Conclusion: The addition of QS in the diet of broiler chicks had positive effects on the breast muscle yield and breast muscle quality, and improved the dry matter digestibility and energy retention by increasing cecal beneficial bacteria counts, thus improving growth performance.

• 농업과학연구
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• 제50권3호
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• pp.313-320
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• 2023

A total of 96 weanling pigs with an initial body weight of 5.96 ± 0.08 kg were randomly allocated to two dietary treatments and fed experimental weaning diets for 36 days in three phases; phase 1: day 1 to 7; phase 2: day 8 to 21, and phase 3: day 22 to 36. Treatments consisted of a basal diet (CON) containing 334.0 g/kg dried whey versus a lactic acid (LA) supplemented diet containing 313.6 g/kg dried whey with 10 g/kg LA during phase 1; a CON diet containing 200.0 g/kg dried whey versus an LA diet containing 186.0 g/kg dried whey with 7 g/kg LA during phase 2. During phase 3, both CON and LA groups were fed a diet without dried whey and LA. Pigs fed the LA diet had a higher average daily feed intake ADFI (p = 0.014) and reduced (p = 0.035) gain-feed ratio compared to pigs fed CON diet in phase 2. In phase 3, the average daily gain and feed intake were both increased (p = 0.026 and; p = 0.010, respectively) in the pigs previously fed the LA diet than those fed the CON diet. The apparent total tract digestibility of dry matter and, nitrogen, and the digestible energy were decreased (p < 0.05) in the LA diet group on day 7; however, increased (p < 0.05) digestibility of dry matter and nitrogen and digestible energy was observed at the end of phase 2 and 3. In conclusion, the inclusion of LA was inferred to have improved the average daily gain, feed intake, and nutrient digestibility during the late weanling period of pigs.

• Animal Bioscience
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• 제37권2호
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• pp.218-227
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• 2024

Objective: The aim of this research was to explore the effects of dietary substitution of alfalfa hay by amaranth hay on production performance, rumen fermentation, nutrient digestibility, serum biochemical parameters and antioxidant ability in dairy cows. Methods: A total of 45 healthy Holstein cows with same parity and similar milk yield and body weight were randomly divided into 3 groups: control diet without amaranth hay (CON) or 50% and 100% alfalfa hay replaced by an equal amount of amaranth hay (dry matter basis, AH1 and AH2, respectively). All the cows were fed regularly 3 times a day at 06:30, 14:30, and 22:30 and had free access to water. The experiment lasted for 60 d. Results: The dry matter intake of CON and AH1 groups was higher (p<0.05) than that of AH2 group. Compared with AH1 group, the milk yield of AH2 group was reduced (p<0.05). Moreover, dietary substitution of alfalfa hay by amaranth hay increased (p<0.05) milk fat, ammonia nitrogen and acetate concentrations. However, the crude protein digestibility of AH2 group was lower (p<0.05) than that of CON group, while an opposite tendency of serum urea nitrogen was found between two groups. The neutral detergent fiber digestibility of AH1 group was increased (p<0.05) when compared to AH2 group. Amaranth hay treatment increased (p<0.05) the serum concentration of glutathione peroxidase in dairy cows. Compared with CON group, the malonaldehyde activity of AH1 group was decreased (p<0.05). Conclusion: Dietary replacing alfalfa hay with amaranth hay (50% ratio) in dairy cows did not affect production performance but improved their antioxidant ability.

• Journal of Animal Science and Technology
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• 제66권2호
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• pp.340-352
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• 2024

This study measured the potential changes of the microbiota in the gastrointestinal tract and energy and nutrient digestibility by supplemental bacteriophages in pigs. Twelve castrated male pigs (initial mean body weight = 29.5 ± 2.3 kg) were surgically cannulated using T-cannula. The animals were housed individually in pens equipped with a feeder and a nipple waterer. The pigs were allotted to 1 of 3 experimental diets in a quadruplicated 3 × 2 Latin square design with 3 experimental diets, 2 periods, and 12 pigs resulting in 8 replicates per diet. The 3 diets were a control mainly based on corn and soybean meal with no antibiotics or bacteriophages, a diet containing 0.1% antibiotics, and a diet containing 0.2% bacteriophages. On day 5 of the experimental period, feces were collected and on days 6 and 7, ileal digesta were collected. Genomic DNA for bacteria were extracted from the ileal digesta and feces and the V4 region of the 16S rRNA gene was amplified. The ileal and fecal digestibility of energy, dry matter, organic matter, crude protein, and fiber was unaffected by dietary antibiotics or bacteriophages. At the phylum level, the supplemental antibiotic or bacteriophage tended to result in a higher proportion of Firmicutes (p = 0.059) and a lower proportion of Bacteroidetes (p = 0.099) in the ileal digesta samples compared with the control group with no difference between the antibiotic and bacteriophage groups. At the genus level, the supplemental antibiotic or bacteriophage tended to result in a higher proportion of Lactobacillus (p = 0.062) and a lower proportion of Bacteroides (p = 0.074) and Streptococcus (p = 0.088) in the ileal digesta compared with the control group with no difference between the antibiotic and bacteriophage groups. In the feces, supplemental antibiotics or bacteriophages reduced the proportion of Bifidobacterium compared with the control group (p = 0.029) with no difference between the antibiotic and bacteriophage groups. Overall, supplemental antibiotics and bacteriophages showed positive effect on the microbiota of in the ileal digesta without largely affecting energy or nutrient digestibility, with no differences between the antibiotic and bacteriophage groups in growing pigs.