• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• Journal of Environmental Science International
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• v.17 no.2
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• pp.211-224
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• 2008

Characteristics of the esterification reaction between free fatty acid in rice bran oil and methanol was investigated in the presence of catalysts, such as PTS(p-toluene sulfonic acid), Amberlyst 15 dry and SCX(silica gel based strong cation exchange resin). While reaction temperature was kept constant at $65^{\circ}C$, initial feed content of free fatty acid was varied from 100% to 1% by addition of pure free fatty acid which was previously made from rice bran oil. Also, the effect of mole ratio of methanol to fatty acid on the final conversion was examined. When esterification of pure free fatty acid was catalyzed by several acids, final conversions were increased in order of Amberlyst 15 dry, SCX and PTS. Using PTS catalyst, initially the reaction proceeded in homogeneous 2nd oder reaction mechanism. However, phase of reaction mixture changed from homogeneous to heterogeneous along the reaction time and then reaction rate was retarded by mass transfer resistance of methanol. Final conversion of free fatty acid in reaction mixture was depended on initial feed content of free fatty acid, and had maximum value at 30% of initial feed free fatty acid content for all kinds of catalysts used. And the final conversion was increased with mole ratio of methanol by the improvement of reaction rate. When initial feed free fatty acid content below 10% and the reaction was catalyzed by PTS, concentration of free fatty acid in reaction mixture was increased in the middle of reaction time by hydrolysis of triglyceride in reaction mixture. Also, if silica gel was added into the reaction mixture which had initial feed free fatty acid content below 50%, final conversion was increased by the adsorption of moisture produced. The SCX catalyst made the esterification reaction of free fatty acid to progress like in case of PTS catalyst. However, when initial feed free fatty acid content below 10%, concentration of free fatty acid in. reaction mixture was decreased monotonically and not increased in the middle of reaction time on the contrary to the case of PTS. Thus, SCX catalyst accomplished more high value of final conversion than PTS catalyst for the initial feed fatty acid content range from 50% to 5% In case of initial feed free fatty acid content of 1% and mole ratio of methanol was 2, concentration of free fatty acid in reaction mixture increased over the initial feed free fatty acid content for all kind of catalysts used. Although SCX catalyst was added into reaction mixture which had 1% of initial feed fatty acid content, final conversion was hardly raised by mole ratio of methanol.

• Korean Journal of Poultry Science
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• v.26 no.1
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• pp.51-56
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• 1999

This experiment was conducted to determine the effect of dietary red pepper seed oil meal (RPSOM) on the performance and the fat pad content in broiler chicks. feeding trial was conducted with 360 birds broiler chicks for 8 weeks. The levels of dietary RPSOM were 0, 5, 10 and 15% and mixed in diet consisting of corn and soybean meal. Body weight, feed intake, feed conversion and mixed in diet consisting of corn and soybean meal. Body weight, feed intake, feed conversion and viability were not significantly different among treatments. The percentage of abdominal fat and skin color were not significantly differents among treatments. The results of the feeding trial show that RPSOM can be used within 10% in broiler diet.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.5
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• pp.367-375
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• 2022

Generally, a proportional-resonant controller is used to eliminate steady-state errors during the voltage-current control of a double-conversion uninterruptible power supply (UPS) in a stationary reference frame. Additionally, the feed-forward control compensating for the load current, which can be considered a disturbance of the voltage controller, can be used to improve the disturbance rejection performance. However, during the parallel operation of UPSs, circulating current can occur between UPS modules when performing both feed-forward control and droop control because feed-forward control reduces the circulating current impedance. This study proposes a feed-forward compensation technique that considers the impedance of circulating current. An additional feed-forward compensation technique is developed to enhance the disturbance rejection performance. The validity of the proposed feed-forward compensation technique is verified by the experiment results of the parallel operation of a 500 W double-conversion UPS module.

• Korean Journal of Organic Agriculture
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• v.12 no.1
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• pp.81-92
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• 2004

The effect of feeding extracts from rhus trees on performance of broiler were performed to investigate development of natural antibiotic in process of broilers production. A total of 320 broiler chicks at 7 day of age were fed the commercial diet and water, water containing 0 ppm (control), 300 ppm (T1), 600 ppm (T2) and 1000 ppm (T3) of extracts from rims trees for 7 weeks. The body weight gain and feed conversion ratio were improvement by feeding extracts from rims trees at 7 to 21 days of age (P<0.05), but amount of feed intake and mortality were not different among the four group. When 21 to 35 days of age, body weight gain, amount of feed intake, feed conversion ratio and mortality were almost same results when 7 to 21days of age, but it was not significantly different. When 35 to 49 days of age, body weight gain in T1 and T3 group was significantly improvement than control group (P<0.05), also feed conversion ratio was improve by feeding extracts from rhus trees. There was a decrease in the microflora population of both E coli. and salmonella in the cecum contents and feaces in broilers by feeding extracts from rhus trees. Emission of ammonia and VFA gas from excreta were significantly decreased at 5 to 10 days of storaged period (P<0.05). The digestibility of dry matter, crude fat, and crude ash of feed were tend to increased in broiler feeding extracts from rims trees. Digestibility of crude protein of feed in broiler three treatmental groups was significantly improved (P<0.05) as compared with those in control group. These results indicated that the feeding extracts from rhus trees of 300 to 1000 ppm of broiler production were improvement in th6 body weight gain, feed conversion ratio, and mortality due to increasing nutrients digestibility from feed, decreasing of microflora population of both E coll. and salmonella in the cecum contents and feaces, decreasing emission of ammonia and VFA gas from excreta.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.377-381
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• 2002

The growth rate, feed conversion efficiency and carcass characteristics of nine native Malpura (M) and eight Awassi ${\times}$ Malpura half bred (AM) male lambs were compared under intensive feeding on 60:40 concentrate and roughage based composite feed. Weaning body weight was similar in the two genetic groups while finishing body weight, total body weight gain and average daily gain during the experiment were higher (p<0.01) in AM than M lambs. The feed conversion efficiency was lower in M than AM lambs with 15.7 and 19.8 per cent feed conversion efficiency, respectively, in the two genetic groups. The dressing yield in terms of preslaughter weight or empty live weight was however similar in the two genetic groups. The loin eye area was also greater (p<0.01) in AM than M lambs. The cutability was similar for the two groups amounting to 33.2, 13.3, 13.2, 23.3 and 16.6% of half carcass, respectively, for leg, loin, rack, neck and shoulder and breast and foreshank. On an average the separable lean, fat and KOH bone content of the half carcass were 48.3, 16.8 and 23.3% for native M and 54.1, 15.0 and 19.0% for AM lambs, respectively. It is concluded that growth rate and feed conversion efficiency were better in Awassi ${\times}$ Malpura half bred than native Malpura lambs while dressing yield and cutability of standard cuts were similar in the two genetic groups.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.3
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• pp.227-230
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• 1991

A comparative study was conducted in total thirty six large while weaner pigs of about 15 kg body weight namely boars, barrows and gilts to evaluate best sex and economic slaughter weight with one standard ration. In 159 days study period feed consumption, growth, feed conversion ratio and carcass quality were judged in all sexes of pigs at 50, 70 and 90 kg body weight. It was noted that upto 70 kg body weight the growth in boars and gills 46.0 and 49.0 kg and feed conversion ratio 4.83 and 4.81 were superior and economical over the barrows, which were 45.5 kg and 4.95. Later on there were too many fluctuations in growth and feed conversion ratio in all sexes of pigs, which would be uneconomical. Carcass quality was also better in boars and gilts than barrows, No boar taint was noted in most of the boar carcasses. Hence it is concluded that boars and gilts can be raised upto the 70 kg body weight for economic pork production.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.1008-1013
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• 2001

This experiment was conducted to determine the effects of enzyme supplementation on the performance of 80 growing-finishing pigs (26.2 kg) fed diets containing either soybean or canola meal. Barley-based diets formulated using either soybean meal or canola meal were fed with or without enzyme (Allzyme Vegpro, Alltech Biotechnology Centre). Eight castrates and twelve gilts were fed each diet. Digestibility of dry matter, crude protein and gross energy was 8.0 (p=0.0001), 7.9 (p=0.0005) and 7.9 (p=0.0003) percent lower for pigs fed diets containing canola meal compared with soybean meal. Enzyme supplementation had no effect on nutrient digestibility (p>0.05). There was a significant interaction between protein source and enzyme for all three nutrients. Over the entire experimental period (26.2 to 77.9 kg), pigs fed canola meal consumed 9.4% less feed (p=0.001), gained weight 20.4% slower (p=0.001) and had a 12.9% poorer feed conversion (p=0.001) than pigs fed soybean meal. Weight gain, feed intake and feed conversion were unaffected by enzyme addition (p>0.05). Castrates gained weight 11.4% faster (p=0.001), consumed 9.3% more feed (p=0.001) and had a 2.6% better feed conversion (p=0.026) than gilts. There was a significant interaction between protein source and sex of pig for feed conversion. Pigs fed diets based on canola meal had a significantly lower carcass value index (p=0.01), lower lean yield (p=0.007) and lower lean depth over the loin (p=0.001) than pigs fed diets based on soybean meal. Enzyme addition significantly increased lean depth over the loin (p=0.01). There was a significant interaction between protein source and enzyme for carcass value index (p=0.04), estimated lean yield (p=0.05) and fat depth over the loin (p=0.05). These results confirm previous studies which have demonstrated poorer pig performance when canola meal completely replaces soybean meal in diets fed to growing-finishing pigs. In addition, the results provide little justification for the inclusion of the Vegpro enzyme in diets fed to pigs of this weight range.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.1
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• pp.1-12
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• 2005

Feed conversion efficiency contributes directly or indirectly on the cost benefit ratio of silkworm rearing and is considered to be an important physiological criterion for evaluating the superiority of silkworm breeds/hybrids. Food intake, assimilation and conversion of indigenous as well as exotic silkworm races are well studied by many researchers. In this review, an attempt has been made to consolidate works on feed conversion aspects of indigenous and exotic silkworm races. The paper also deals with the effect of various factors viz., nutritional, environmental and feeding on food assimilation and conversion parameters of mulberry silkworm.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.2
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• pp.187-193
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• 1991

Almost 1/4 of all the coconuts in the world is produced in the Philippines. During periods of high supply of coconuts it would be better to feed coconut meat to farm animals for conversion into meat and eggs. Three studies were conducted at the Visayas State College of Agriculture, Baybay, Leyte, Philippines from April, 1983 to April, 1985 to determine the response of Mallard ducks, Muscovy ducks and broilers to fresh coconut meat supplementation in their diets. Results showed that Mallard ducks on ration with coconut meat performed similarly with those on ration without coconut meat. Feed cost per dozen eggs was reduced by 28-30% with coconut meat. Feed cost per unit gain of muscovy ducks was reduced by 32-37% by coconut meat supplementation. With broilers, feed conversion, gain in weight and breast weight were significantly improved by coconut meat supplementation. Return-above-feed cost increased with increasing level of coconut meat in the ration.