• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1466-1472
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• 2012

A bacterial isolate derived from soil samples near a cattle farm was found to display extracellular phytase activity. Based on 16S rRNA sequence analysis, the strain was named Bacillus sp. T4. The optimum temperature for the phytase activity toward magnesium phytate (Mg-$InsP_6$) was $40^{\circ}C$ without 5 mM $Ca^{2+}$ and $50^{\circ}C$ with 5 mM $Ca^{2+}$. T4 phytase had a characteristic bi-hump two pH optima of 6.0 to 6.5 and 7.4 for Mg-$InsP_6$. The enzyme showed higher specificity for Mg-$InsP_6$ than sodium phytate (Na-$InsP_6$). Its activity was fairly inhibited by EDTA, $Cu^{2+}$, $Mn^{2+}$, $Co^{2+}$, $Ba^{2+}$ and $Zn^{2+}$. T4 phytase may have great potential for use as an eco-friendly feed additive to enhance the nutritive quality of phytate and reduce phosphorus pollution.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.231-242
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• 1990

A study is reported which investigated the additive nature of digestible energy (DE) from dietary nutrients and to estimate the relative energy values of different energy-yielding nutrients in practical trout diets. A growth study was conducted over 12 weeks with 6 diets. Rainbow trout (Oncorhynchus mykiss) were fed diets once a day ad libitum. Digestible energy values determined and calculated had direct relationship indicating additive nature of such values for feed ingredients. Overall growth performance was best in a diet containing 33% digestible protein (DP) with a DP/DE ratio of 18.6. A reduction in digestible protein level with the same DP/DE rat io led to a significant decrease in growth and feed efficiency. The increase of 7% of lipid with concomitant decrease in protein resulted in the relative gain of 130% in growth and nutrient retention, suggesting that 1 g of lipid is equal to about 1.3 g of proteins in terms of net energetic value. Replacement of 10% of dietary lipid by carbohydrates led to a slight decrease in energy retention efficiency but to a great increase in lipid retention efficiency (130%) showing that dietary carbohydrates led to increased lipogenesis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.546-551
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• 2013

This study examined the effects of the dietary inclusion of Porphyra and sea tangle Laminaria japonica on the growth, feed utilization, body composition, and plasma chemistry of juvenile Korean rockfish Sebastes schlegeli. Eight hundred and forty juvenile fish averaging 5.0 g were allocated 40 fish per tank to 21 180-L flow-through tanks. Seven experimental diets were prepared: control (Con) without additive, 0.5 and 1% Porphyra extract (PE), 3% Porphyra powder (PP), 0.5 and 1% sea tangle extract (STE) and 3% sea tangle powder (STP), referred to as PE-0.5, PE-1, PP-3, STE-0.5, STE-1, and STP-3, respectively. Each additive was included in the experimental diet at the expense of the same amount of wheat flour. Each experimental diet was fed to triplicate groups of fish. The experimental diets had no effect on the survival, weight gain or specific growth rate of the fish, feed consumption, feed efficiency ratio, protein efficiency ratio, protein retention, hepatosomatic index, condition factor, moisture or crude protein content of the entire body excluding the liver or moisture, crude protein or crude lipid content of the liver. None of the plasma parameters were affected by the experimental diets. Based on these results, the dietary inclusion of Porphyra and sea tangle did not affect the growth, feed utilization, body composition or plasma chemistry of juvenile Korean rockfish.

• Journal of fish pathology
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• v.33 no.2
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• pp.177-184
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• 2020

In an attempt to find a feed additive showing an anti-scuticociliate effect, extracts from Citrus unshiu Peel were tested against virulent scuticociliate infection. The most effective anti-scuticociliate killing activity in vitro was observed in the extract squeezed from homogenizing water-soaked dried tangerine peel (DTP). In addition, we have investigated the effect of DTP as a feed additive on growth rate and anti-parasitic activity of olivaceus flounder. DTP extract added diets (0.1, 0.5, 1, and 5%/feed weight) were fed to flounder for 7 days for checking a growth rate and 14 days for a challenging test. As a result, the feed conversion rate was significantly improved only in 1% DPT extract group compared to the control and 0.5% DTP extract fed group showed 100% of survival rate in the challenge test, all of which indicating that DTP extract would be a potential feed additive against scuticociliatosis.

• Korean Journal of Veterinary Service
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• v.44 no.4
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• pp.247-256
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• 2021

The recombinant lysozyme-HJL34 proteins were expressed and purified using commercial Escherichia (E.) coli expression system. Stx2e⁺ F18⁺ E. coli, Actinobacillus pleuropneumoniae (APP), Streptococcus (S.) suis, and Clostridium (C.) perfringens strains were isolated from pigs. The minimum inhibitory concentrations (MICs) of the recombinant lysozyme-HJP34 proteins were examined by means of the microtiter plate method, according to the NCCLS recommendations. The possibility of its as the alternatives to antibiotics was tested in piglets. The MICs were determined as 75 ㎍/mL, 300 ㎍/mL, 75 ㎍/mL, 35.5 ㎍/m against Stx2e⁺ F18⁺ E. coli, APP, S. suis, C. perfringens, respectively. A total of 25 piglets were divied 5 groups. The piglets in group A~C were fed with commercial feed and those in groups D, E were fed with commercial feedstuff. All piglets in groups B~E were challenged with virulent Stx2e⁺ F18⁺ E. coli, APP, S. suis strains. Groups C and D were treated with antimicrobial from 24 h after challenge. All piglets in group B died within 3 days after challenge. Among 5 piglets in groups C and D piglets, 80% survived after challenge. Among group E piglets, 60% were alive until the end of this study. Therefore, this study indicates that recombinant lysozyme-HJP34 proteins is a suitable possibility as a feed additive for reduction of diseases by bacterial pathogens in piglet feed.

• Korean Journal of Veterinary Research
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• v.14 no.2
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• pp.237-241
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• 1974

A number of chemotherapeutic agents, namely antibiotics, sulfonamides and nitrofuran derivatives have been used, as a fred additive, for the purposes of growth improvement of chicken, increase of feed efficiency, decrease of animal mortality, and disease prevention. In these experiments, furamizole which is one of nitrofuran derivatives and feed additive was test, in field, its antibacterial activity against Mycoplasma gallisepticum causing air sac disease, its effect on pullorum disease control, its effect on the lowering the mortality of chicken and finally the increase of feed efficiency. Throughout the studies, furamizole, in concentration of 0.025% in feed fed to baby chicken continuously resulted as following: 1. Tested chicken showed no avian mycoplasma infection compared to 3.7% outbreak in control chicken. 2. Tested chicken showed a low degree of outbreak of pullorum disease. However, its outbreak was much more surpresed compared to that of control chicken. 3. Total mortality rate of 5.5% and 30.8% were obtained in test and control chicken respectively. 4. Feed efficiency were 2.83 and 2.97 in test and control chicken respectively.

• Animal Bioscience
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• v.37 no.2
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• pp.161-172
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• 2024

For sustainable development, better performance, and less gas pollution during rumen fermentation, there is a need to find a green and safe feed additive for ruminants. Cysteamine (CS) is a biological compound naturally produced in mammalian cells. It is widely used as a growth promoter in ruminants because of its ability to control hormone secretions. It mainly controls the circulating concentration of somatostatin and enhances growth hormone production, leading to improved growth performance. CS modulates the rumen fermentation process in a way beneficial for the animals and environment, leading to less methane production and nutrients loss. Another beneficial effect of using CS is that it improves the availability of nutrients to the animals and enhances their absorption. CS also works as an antioxidant and protects the cells from oxidative damage. In addition, CS has no adverse effects on bacterial and fungal alpha diversity in ruminants. Dietary supplementation of CS enhances the population of beneficial microorganisms. Still, no data is available on the use of CS on reproductive performance in ruminants, so there is a need to evaluate the effects of using CS in breeding animals for an extended period. In this review, the action mode of CS was updated according to recently published data to highlight the beneficial effects of using CS in ruminants.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.500-506
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• 2017

To investigate the potential applications of bacterial heme, aminolevulinic acid synthase (HemA) was expressed in a Corynebacterium glutamicum HA strain that had been adaptively evolved against oxidative stress. The red pigment from the constructed strain was extracted and it exhibited the typical heme absorbance at 408 nm from the spectrum. To investigate the potential of this strain as an iron additive for swine, a prototype feed additive was manufactured in pilot scale by culturing the strain in a 5 ton fermenter followed by spray-drying the biomass with flour as an excipient (biomass: flour = 1:10 (w/w)). The 10% prototype additive along with regular feed was supplied to a pig, resulting in a 1.1 kg greater increase in weight gain with no diarrhea in 3 weeks as compared with that in a control pig that was fed an additive containing only flour. To verify if C. glutamicum-synthesized heme is a potential electron carrier, lactic acid bacteria were cultured under aerobic conditions with the extracted heme. The biomasses of the aerobically grown Lactococcus lactis, Lactobacillus rhamosus, and Lactobacillus casei were 97%, 15%, and 4% greater, respectively, than those under fermentative growth conditions. As a potential preservative, cultures of the four strains of lactic acid bacteria were stored at $4^{\circ}C$ with the extracted heme and living lactic acid bacterial cells were counted. There were more L. lactis and L. plantarum live cells when stored with heme, whereas L. rhamosus and L. casei showed no significant differences in live-cell numbers. The potential uses of the heme from C. glutamicum are further discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.5
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• pp.624-630
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• 2001

Two experiments on the effects of molasses additive on cassava tops silage quality to its feed intake and digestibility by growing Holstein$\times$local crossbred heifers were carried out. Sixteen plastic bags of one meter diameter and two meters length were allocated in a $2{\times}2$ factorial design with four replicates in the ensiling study, with and without the molasses additive and with two storage times (2 and 3 months). The silage produced in the first experiment was used in the feed intake and digestibility study. Six crossbred Holstein heifers, 160-180 kg live weight, were randomly allocated in a $3{\times}2$ change-over design to three treatments: Guinea grass ad libitum, 70% of grass ad libitum with a supplement of non-molasses cassava silage ad libitum, and 70% of grass ad libitum with a supplement of molasses cassava silage ad libitum. Ensiling was shown to be a satisfactory method for preservation of cassava tops. The HCN content was significantly reduced from $840mg\;kg^{-1}$ to 300 or $130mg\;kg^{-1}$, depending on storage period. The tannin content was not significantly changed. Molasses additive resulted in lower pH, Crude Protein (CP), NDF and higher DM content but did not otherwise affect chemical composition. The voluntary feed intake per 100 kg live weight of the heifers was 2.59, 2.65 and 2.91 kg DM of Guinea grass, non-molasses cassava tops silage and molasses cassava tops silage diet, respectively. Crude protein intake was significantly improved in the cassava tops silage diets. The apparent digestibility of DM, OM, CP, NDF and ADF decreased with the silage supplement diets. No significant difference in digestibility was found between the non-molasses and molasses silage diets. The digestibility coefficient of DM, OM, CP, NDF, ADF in non-molasses cassava tops silage and molasses cassava tops silage was 49.4, 52.1, 45.81, 36.6, 27.7 and 49.7, 51.9, 47.55, 28.1, 19.5, respectively. It is concluded that cassava tops can be preserved successfully by ensiling and that cassava tops silage is a good feed resource for cattle.

• Journal of Environmental Science International
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• v.27 no.9
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• pp.803-807
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• 2018

This study evaluated the duck growth performance and the economic benefits on using illite as a feed additive for ducks. Illite powder at three levels (0%, 1%, and 1.5%) was added to commercial duck diets, and fed to 180 one-day-old ducks (Pekin, 3 replicates, 20 ducks per pen) using a randomized block design for 39 days. During the experimental period, there were no significant growth performance differences between treatments (p>0.05), except with the feed conversion ratio (p<0.05), for all periods (8-39 days). In addition, the dietary supplementation of 1% and 1.5% illite did not significantly improve (p>0.05) Feed Intake Cost (FIC), Weight Gain Value (WGV), Meat Production Cost (MPC), Economic Efficiency (EE), Profitability (P), or cost benefit ratio for 8 to 21 d, 22 to 39 d, and 8 to 39 d. However, the differences in meat production cost and profitability between treatments were statistically significant (p<0.05) for all periods (8-39 d). In conclusion, adding 1% and 1.5% illite to duck diets is not beneficial for improving either the duck growth performance or the economic indicators.