• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.320-325
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• 2009

The present study was carried out to investigate the acute oral toxicity and anti-obesity effects of a diglyceride preparation containing conjugated linoleic acid (DG+CLA). To test its acute oral toxicity, the DG+CLA was injected into 30 rats (15 males and 15 females) at dosage of 2,000 mg/kg and 5,000 mg/kg. Mortality rates, clinical signs, and body weight changes were monitored for 14 days following administration. According to the results, the lethal dose ($LD_50$) of DG+CLA was determined as >5,000 mg/kg in both sexes. There were no significant changes in general conditions, clinical signs, body weight, and gross lesions between the vehicle control and DG+CLA groups. For the anti-obesity studies, obese Zucker rats were randomly divided into 4 groups and fed saline, soybean oil, diglyceride, and DG+CLA, respectively, for 8 weeks. The DG+CLA groups presented significant differences in body weight, food efficiency ratio, serum lipid levels, and fat weight. Overall, the results showed that the DG+CLA did not have acute oral toxicity and reduced body weight, serum lipid levels, and fat gain.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1425-1429
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• 2005

Megaspahera elsdenii YJ-4, which was previously isolated as a producer of trans-10, cis-12 CLA, was studied for its carbon source on the CLA production. M. elsdenii YJ-4, was incubated with glucose and lactose, and cultured in batch and continuous culture systems with linoleic acid at various pHs to investigate CLA production. Batch cultures of the ruminal bacterium, M. elsdenii YJ-4, were resistant to stearic acid and linoleic acid, and little growth inhibition was observed even when the fatty acid concentration in the culture was as much as 4 mg $ml^{-1}$. Stationary phase batch cultures (0.25 mg bacterial protein $ml^{-1}$) that had been grown on lactate and incubated with linoleic acid (0.20 mg $ml^{-1}$) produced approximately 12 ${\mu}g$ trans-10, cis-12 CLA mg $protein^{-1}$ and little cis-9, trans-11 CLA was detected. Some linoleic acid was converted to hydrogenated products (chiefly stearic acid), but these fatty acids were less than 5 ${\mu}g$ mg bacterial $protein^{-1}$. Stationary phase batch cultures that had been grown on glucose produced at least 3-fold less trans-10, cis-12 CLA than ones grown on lactate. Cells from lactate-limited continuous cultures produced less trans-10, cis-12 CLA than those from batch culture, but only if the pH was greater than 6.4. When the pH of the lactate-limited continuous cultures was lower than 6.4, trans-10, cis-12 CLA and hydrogenated products declined. Cells from glucose-limited continuous cultures produced less trans-10, cis-12 CLA and hydrogenated products than the cells that had been limited by lactate, but pH had little impact on this production. These results support the idea that M. elsdenii YJ-4 could be one of the major producers of trans-10, cis-12 CLA which causes cows to produce milk with a low fat content.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.663-670
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• 2008

The effect of supplementing the diet of grazing dairy cows with fish oil (FO) and linseed oil (LSO) on milk conjugated linoleic acid (CLA) was investigated. Sixteen Holstein cows (17019 DIM) were assigned into two groups and fed a grain supplement (8.0 kg/d; DM basis) containing 800 g of saturated animal fat (CONT) or 200 g FO and 600 g LSO (FOLSO). All cows grazed together on Sudan grass pasture ad libitum and were fed the treatment diets for 3 wks. Cows were milked twice a day and milk samples were collected during the last three days of the trial. Milk production (24.89 and 22.45 kg/d), milk protein percentage (2.76 and 2.82) and milk protein yield (0.68 and 0.64 kg/d) for the CONT and FOLSO diets, respectively, were not affected (p>0.05) by treatment diets. Milk fat percentage (3.90 and 2.86) and milk fat yield (0.97 and 0.64 kg/d) were lower (p<0.05) with the FOLSO diet compared with the CONT diet. The concentration and yield of milk cis-9 trans-11 CLA were higher (p<0.05) with the FOLSO diet (2.56% of total FA and 16.44 g/d, respectively) than the CONT diet (0.66% of total FA and 6.44 g/d, respectively). The concentrations of milk trans C18:1 and vaccenic acid (VA) were higher (p<0.05) with the FOLSO diet (13.53 and 7.48% of total FA, respectively) than the CONT diet (3.69 and 2.27% of total FA, respectively). In conclusion, supplementing the diet of grazing cows with FO and LSO increased milk cis-9 trans-11 CLA content but reduced milk fat content and yield.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.7
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• pp.962-970
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• 2012

This study aimed to investigate the effects of ruminal infusion of garlic oil (GO) on fermentation dynamics, fatty acid (FA) profile, and abundance of bacteria involved in biohydrogenation in the rumen. Six wethers fitted with ruminal fistula were assigned to two groups for cross-over design with a 14-d interval. Each 30-d experimental period consisted of a 27-d adaptation and a 3-d sample collection. Goats were fed a basal diet without (control) or with GO ruminal infusion (0.8 g/d). Ruminal contents collected before (0 h) and at 2, 4, 6, 8, and 10 h after morning feeding were used for fermentation analysis, and 0 h samples were further used for FA determination and DNA extraction. Garlic oil had no influence on dry matter intakes of concentrate and hay. During ruminal fermentation, GO had no effects on total VFA concentration and individual VFA molar proportions, whereas GO increased the concentrations of ammonia nitrogen and microbial crude protein (p<0.05). Compared with control, GO group took a longer time for total VFA concentration and propionate molar proportion to reach their respective maxima after morning feeding. The ratio of acetate to propionate in control reduced sharply after morning feeding, whereas it remained relatively stable in GO group. Fatty acid analysis showed that GO reduced saturated FA proportion (p<0.05), while increasing the proportions of C18, t11-18:1 (TVA), c9,t11-conjugated linoleic acid (c9,t11-CLA), t10,c12-CLA, and polyunsaturated FA (p<0.05). The values of TVA/(c9,t11-CLA+TVA) and C18:0/(TVA+C18:0) were reduced by GO (p<0.05). Real-time PCR showed that GO tended to reduce Butyrivibrio proteoclasticus abundance (p = 0.058), whereas GO had no effect on total abundance of the Butyrivibrio group bacteria. A low correlation was found between B. proteoclasticus abundance and C18:0/(TVA+C18:0) (p = 0.910). The changes of fermentation over time suggested a role of GO in delaying the fermentation process and maintaining a relatively modest change of ruminal environment. The inhibitory effects of GO on the final step of biohydrogenation may be related to its antibacterial activity against B. proteoclasticus and other unknown bacteria involved.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.6
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• pp.796-806
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• 2015

To evaluate the effects of feeding linseed oil or/and sunflower oil mixed with fish oil on milk yield, milk composition and fatty acid (FA) profiles of dairy cows fed a high-concentrate diet, 24 crossbred primiparous lactating dairy cows in early lactation were assigned to a completely randomized design experiment. All cows were fed a high-concentrate basal diet and 0.38 kg dry matter (DM) molasses per day. Treatments were composed of a basal diet without oil supplement (Control), or diets of (DM basis) 3% linseed and fish oils (1:1, w/w, LSO-FO), or 3% sunflower and fish oils (1:1, w/w, SFO-FO), or 3% mixture (1:1:1, w/w) of linseed, sunflower, and fish oils (MIX-O). The animals fed SFO-FO had a 13.12% decrease in total dry matter intake compared with the control diet (p<0.05). No significant change was detected for milk yield; however, the animals fed the diet supplemented with SFO-FO showed a depressed milk fat yield and concentration by 35.42% and 27.20%, respectively, compared to those fed the control diet (p<0.05). Milk c9, t11-conjugated linoleic acid (CLA) proportion increased by 198.11% in the LSO-FO group relative to the control group (p<0.01). Milk C18:3n-3 (ALA) proportion was enhanced by 227.27% supplementing with LSO-FO relative to the control group (p<0.01). The proportions of milk docosahexaenoic acid (DHA) were significantly increased (p<0.01) in the cows fed LSO-FO (0.38%) and MIX-O (0.23%) compared to the control group (0.01%). Dietary inclusion of LSO-FO mainly increased milk c9, t11-CLA, ALA, DHA, and n-3 polyunsaturated fatty acids (PUFA), whereas feeding MIX-O improved preformed FA and unsaturated fatty acids (UFA). While the lowest n-6/n-3 ratio was found in the LSO-FO, the decreased atherogenecity index (AI) and thrombogenicity index (TI) seemed to be more extent in the MIX-O. Therefore, to maximize milk c9, t11-CLA, ALA, DHA, and n-3 PUFA and to minimize milk n-6/n-3 ratio, AI and TI, an ideal supplement would appear to be either LSO-FO or MIX-O.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.234-239
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• 2012

The objective of this study was to evaluate the effects of forage level and oil supplement on selected strains of rumen bacteria believed to be involved in biohydrogenation (BH). A continuous culture system consisting of four fermenters was used in a $4{\times}4$ Latin square design with a factorial arrangement of treatments, with four 10 d consecutive periods. Treatment diets were: i) high forage diet (70:30 forage to concentrate (dry matter basis); HFC), ii) high forage plus oil supplement (HFO), iii) low forage diet (30:70 forage to concentrate; LFC), and iv) low forage plus oil supplement (LFO). The oil supplement was a blend of fish oil and soybean oil added at 1 and 2 g/100 g dry matter, respectively. Treatment diets were fed for 10 days and samples were collected from each fermenter on the last day of each period 3 h post morning feeding. The concentrations of vaccenic acid (t11C18:1; VA) and c9t11 conjugated linoleic acid (CLA) were greater with the high forage diet while the concentrations of t10 C18:1 and t10c12 CLA were greater with the low forage diet and addition of oil supplement increased their concentrations at both forage levels. The DNA abundance of Anaerovibrio lipolytica, and Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) were lower with the low forage diets but not affected by oil supplement. The DNA abundance of Butyrivibrio fibrisolvens stearic acid producer subgroup (Butyrivibrio SA) was not affected by forage level or oil supplement. In conclusion, oil supplement had no effects on the tested rumen bacteria and forage level affected Anaerovibrio lipolytica and Butyrivibrio VA.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.739-747
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• 2018

The low solubility and high-cost recovery of Propionibacterium acnes polyunsaturated fatty acid isomerase (PAI) are key problems in the bioproduction of high value-added conjugated linoleic acid (CLA). To improve the solubility of recombinant PAI, six chaperone proteins were coexpressed with PAI. Introduction of GroELS proteins dramatically improved the PAI solubility from 29% to 97%, with increased activity by 57.8%. Combined expression of DnaKJ-GrpE and GroELS proteins increased the activity by 11.9%. In contrast, coexpression of DnaKJ-GrpE proteins significantly reduced the activity by 57.4%. Plasmids pTf16 harboring the tig gene and pG-Tf2 containing the tig and groEL-groES genes had no visible impact on PAI expression. The lytic protein E was then introduced into the recombinant Escherichia coli to develop a cell autolysis system. A 35% activity of total intracellular PAI was released from the cytoplasm by suspending the lysed cells in distilled water. The PAI recovery was further improved to 81% by optimizing the release conditions. The lipase from Rhizopus oryzae was also expressed in E. coli, with an extracellular activity of 110.9 U/ml. By using the free PAI and lipase as catalysts, a joint system was established for producing CLA from sunflower oil. Under the optimized conditions, the maximum titer of t-10,c-12-CLA reached 9.4 g/l. This work provides an effective and low-cost strategy to improve the solubility and recovery of the recombinant intracellular PAI for further large-scale production of CLA.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1364-1373
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• 2012

Four crossbred (75% Holstein Friesian) lactating dairy cows, with an average live weight of $418{\pm}5$ kg and $36{\pm}10$ d in milk were randomly assigned according to a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design to evaluate the effects of cassava hay (CH) and rice bran oil (RBO) on feed intake, nutrient digestibility, ruminal fermentation, milk yield, and milk composition. Factor A was non-supplementation or supplementation with CH in the concentrate. Factor B was supplementation with RBO at 0% or 4% in the concentrate mixture. The four dietary treatments were (T1) control (Concentrate with non-CH plus 0% RBO; C), (T2) Concentrate with CH plus 0% RBO (CH), (T3) Concentrate with non-CH plus 4% RBO (RBO), and (T4) Concentrate with CH plus 4% RBO (CHRBO). The cows were offered concentrate, at a ratio of concentrate to milk production of 1:2, and urea-lime treated rice straw was fed ad libitum. Urea-lime treated rice straw involved 2.5 g urea and 2.5 g $Ca(OH)_2$ (purchased as hydrated lime) in 100 ml water, the relevant volume of solution was sprayed onto a 100 g air-dry (91% DM) straw, and then covering the stack with a plastic sheet for a minimum of 10 d before feeding directly to animals. The CH based concentrate resulted in significantly higher roughage intake and total DM intake expressed as a percentage of BW (p<0.05). Ruminal pH, $NH_3$-N, BUN and total VFA did not differ among treatments, while RBO supplementation increased propionate, but decreased acetate concentration (p<0.05). Furthermore, the population of total ruminal bacteria was significantly lower on the RBO diet (p<0.05). In contrast, the total ruminal bacteria and cellulolytic bacteria on the CH diet were higher than on the other treatments. Supplementation with CH increased (p<0.05) F. succinogens and R. flavefaciens populations, whereas the populations of B. fibrisolvens and M. elsdenii were increased on the RBO diet. In addition, supplementation with CH and RBO had no effect on milk production and composition in dairy cows, while fatty acid composition of milk was influenced by RBO supplementation, and resulted in significantly lower (p<0.05) concentrations of both short-chain and medium-chain FA, and increased (p<0.05) the proportion of long-chain FA in milk fat, as well as significantly increased cis-9, trans-11 CLA and total CLA. In conclusion, RBO or CH exhibited specific effects on DMI, rumen fermentation, microbial population, milk yield and composition in lactating dairy cows, which were not interactions between CH and RBO in the diets. Feeding lactating dairy cows with RBO could improve fatty acid in milk fat by increasing cis-9, trans-11 CLA.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.7
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• pp.976-986
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• 2015

The present study was conducted to determine the effects of lipid sources with different fatty acids profile on meat fatty acids profile and beef quality traits of Nellore. A total of 45 Nellore animals with an average initial body weight of $419{\pm}11kg$ (at $15{\pm}2mo$) were distributed in a completely randomized design consisting of 5 treatments and 9 replicates. The roughage feed was maize silage (600 g/kg on a dry matter [DM] basis) plus concentrate (400 g/kg on a DM basis). The dietary treatments were as follows: without fat (WF), palm oil (PO), linseed oil (LO), protected fat (PF), and soybean grains (SG). No effects of lipid sources were observed (p>0.05) on beef color, pH, water-holding capacity, and sarcomere length. Beef from cattle fed PO had greater shear-force values (p<0.05) compared to beef from cattle fed WF. Deposition of main unsaturated fatty acids (oleic, linoleic, and linolenic) was greater in treatments WF, SG, and LO, respectively, while the values of conjugated linoleic acid (CLA) were greater when animals were fed LO. The inclusion of LO in the diet enhances the concentration of CLA in longissimus muscle and subcutaneous fat besides improving the atherogenicity index and elongase activity. As such, LO can be used with the aim to improve the quality of beef from confined Nellore cattle. Conversely, the use of PO is not recommended since it may increase the concentration of undesirable unsaturated fatty acids in muscle and subcutaneous fat, shear-force and the atherogenicity index.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.225-229
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• 2018

Objective: This experiment was designed to evaluate the effect of supplementation with soybean or canola oil on milk production and the composition of long chain fatty acids as well as weight changes in the goats and their kids. Methods: Thirty nine mulitparous crossed Alpine${\times}$Nubian goats (initial body weight [BW] $43.5{\pm}1.7kg$) from the day of parturition were assigned to the treatments: grazing control (n = 15); grazing plus 20 mL/goat/d of supplemental soybean oil (n = 12); and grazing plus 20 mL/goat/d of supplemental canola oil (n = 12) from November 26, 2014 to March 7, 2015. The planned contrasts were: CI (control vs supplemented with oils); CII (soybean vs canola oil) to compare the treatment effects. Results: The vegetable oil supplementation reduced weight losses in lactating goats (CI: -0.060 vs 0.090 kg/d; p = 0.03) but did not improve milk production or affect kids' growth. The content of C4, C6, C8, C10, C11, C14, and C18:1n9t in the milk was increased (p<0.05) with respect to control. However, C12, C14, C16, C18, C18:1n9c, C18:2n6c, and C18:3n3 were reduced (p<0.05) in supplemented goats. Conjugated linoleic acid (CLA) was increased (p<0.05) in goats supplemented with oils compared to the control group. Conclusion: Supplementation with 20 mL/d of soybean or canola oil did not affect milk production or kids' performance; however, it increased CLA concentration and reduced the reduced weight losses in lactating goats.