• The Journal of the Acoustical Society of Korea
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• v.19 no.4
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• pp.101-106
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• 2000

This study deals with the relationship between the magnitude of ultrasonic nonlinear parameter B/A, sound speed of amount of fat present in biological media for measuring B/A system using a wide band ultrasonic transducer. To represent this case, mixtures of egg white and egg yolk were studied. Even though the differences in density and sound speed of the two egg components were within 1% of each other, B/A were increases parabolically as a function of the fat density, which is not in agreement with the Yoshizumi et al's suggestion. In skim milk that does not contain fat, both the B/A and the sound speed increase with the solubility. It is proposed that protein could affect these values.

• 월간낙농육우
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• v.32 no.5
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• pp.80-86
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• 2012

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.611-617
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• 2009

This study was aimed at a genetic evaluation of Iranian Holstein cattle for milk and fat yields and calculating daughter yield deviation (DYD) of bulls. The data file that was used in this research included 367,943 first three lactation records of 186,064 Holstein cows which calved between 1983 and 2006 in 11,806 herd-year-season groups. The model included herd-year-season of calving and age at calving as fixed effects and animal and permanent environment as random effects. Mean breeding values of cows for each year were regressed on birth year to estimate genetic trends. Genetic trends in milk and fat yields were greater for cows born after 1997 (59.38 kg/yr and 1.11 kg/yr for milk yield and fat yield, respectively). Animal evaluations were partitioned into contribution from parent average, yield deviation (YD) and progeny. DYD of bulls was calculated as described by VanRaden and Wiggans (1991). DYD provides an indication of the performance of the daughters of a bull without consideration of his parents or sons. Variance of bull DYD was greater than variance of their predicted transmitting ability (PTA). Correlation of bull DYD and PTA was dependent on the number of daughters and when this increased, the correlation of DYD and PTA was increased. Also as lactation number of daughters increased, the correlation of bull DYD and PTA was increased.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.60-64
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• 1985

To utilize microbial lipases for hydrolysis of milk fat, optimum reaction conditions and characteristics of enzymatic reactions of lipases originated from Rhizopus delemar, Mucor sp., and Candida cylindracea were investigated. Optimum pH and temperature were pH 5.6 and $45^{\circ}C$ for Rhizopus delemar lipase, pH7.5 and $35^{\circ}C$ for Mucor sp. lipase, and pH7.5 and $35^{\circ}C$ for Candida cylindracea lipase. Optimum lipase concentration and optimum substrate concentration were $600{\sim}800\;units/ml$ and 20% milk fat, regardless of their origin. Km values were 6.06% milk fat for Rhizopus delemar lipase, 7.69% for Mucor sp. lipase and 7.99% for Candida cylindracea lipase. Rate of lipid hydrolysis was Rhizopus delemar lipase>Mucor sp. lipase>Candida cylindracea lipase. As the reaction time was extended, liberation of short chain fatty acids was increased. After 8 hours reaction, capric acid content significantly increased with Candida cylindracea lipase, palmitic acid with Mucor sp. lipase and butyric acid with Rhizopus delemar lipase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.75-81
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• 2003

Rheological properties of micronized full-fat soyflour (MFS ) milk were determined according to solid content, heat-treatment and type of coagulants. Heat-treated MFS milk showed a pseudoplastic flow pattern. The consistency and flow index of heated MFS milk was greatly affected by increasing the concentration of MFS and/or soy protein isolate (SPI). Apparent viscosity of MFS milk was gradually decreased by heating below 6$0^{\circ}C$, but was drastically increased by raising temperature further. Addition of coagulants and SPI resulted in dropping the temperature that allows to increase apparent viscosity drastically. A coagulant for MFS tofu was formulated based on the gelling Property of a single coagulant. The textural properties of MFS tofu were improved using 7.1% total protein fortified with SPI.

• Journal of Animal Science and Technology
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• v.60 no.7
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• pp.18.1-18.12
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• 2018

Background: Xanthosine treatment has been previously reported to increase mammary stem cell population and milk production in cattle and goats. However, the underlying molecular mechanisms associated with the increase in stem cell population and milk production remain unclear. Methods: Primiparous Beetal goats were assigned to the study. Five days post-partum, one mammary gland of each goat was infused with xanthosine (TRT) twice daily ($2{\times}$) for 3 days consecutively, and the other gland served as a control (CON). Milk samples from the TRT and CON glands were collected on the 10th day after the last xanthosine infusion and the total RNA was isolated from milk fat globules (MEGs). Total RNA in MFGs was mainly derived from the milk epithelial cells (MECs) as evidenced by expression of milk synthesis genes. Significant differentially expressed genes (DEGs) were subjected to Gene Ontology (GO) terms using PANTHER and gene networks were generated using STRING db. Results: Preliminary analysis indicated that each individual goat responded to xanthosine treatment differently, with this trend being correlated with specific DEGs within the same animal's mammary gland. Several pathways are impacted by these DEGs, including cell communication, cell proliferation and anti-microbials. Conclusions: This study provides valuable insights into transcriptomic changes in milk producing epithelial cells in response to xanthosine treatment. Further characterization of DEGs identified in this study is likely to delineate the molecular mechanisms of increased milk production and stem or progenitor cell population by the xanthosine treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.3
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• pp.342-348
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• 2014

This study was conducted to examine the effects of condensed tannins (CT) from Ficus bengalensis leaves on the feed utilization, milk production and health status of crossbred cows. Eighteen crossbred dairy cows at their second and mid lactation (avg. BW $351.6{\pm}10.6$ kg) were randomly divided into two groups of nine each in a completely randomized block design and fed two iso-nitrogenous supplements formulated to contain 0% and 1.5% CT through dried and ground leaves of Ficus bengalensis. The diets were designated as CON and FBLM, respectively and fed to cows with a basal diet of rice straw to meet requirements for maintenance and milk production. The daily milk yield was significantly (p<0.05) increased due to supplementation of FBLM diet. The 4% fat corrected milk yield was also significantly (p<0.01) higher due to increased (p<0.05) milk fat in cows under diet FBLM as compared to CON. The inclusion of CT at 1.5% in the supplement did not interfere with the feed intake or digestibility of DM, OM, CP, EE, NDF, and ADF by lactating cows. Digestible crude protein (DCP) and total digestible nutrients (TDN) values of the composite diets were comparable between the groups. The blood biochemical parameters remained unaltered except significantly (p<0.05) lowered serum urea concentration in cows fed FBLM diet. There was a significant (p<0.05) increase intracellular reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activity in cows supplemented with condensed tannins. The total thiol group (T-SH) was found to be higher with reduction in lipid peroxidation (LPO) in cows of FBLM group. The cost of feeding per kg milk production was also reduced due to supplementation of Ficus bengalensis leaves. Therefore, a perceptible positive impact was evident on milk production and antioxidant status in crossbred cows during mid-lactation given supplement containing 1.5% CT through Ficus bengalensis leaves.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.47-55
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• 2008

The objectives of this study were: 1) to develop the sensory lexicons of milk marketed in Korea, 2) to investigate the effects of pasteurization and milk composition on the sensory qualities of milk, and 3) to evaluate the correlation between descriptive analysis and the electronic nose method. Electronic nose and descriptive analyses were conducted to analyze the sensory characteristics of 14 milk samples. The 14 samples were provided from 4 manufacturers with different pasteurization methods, and varied in fat, calcium, and lactose content. Twenty-six sensory lexicons were developed to describe the sensory characteristics of the samples. The low temperature, long-time processed milk had a distinctive 'bi-rim' flavor regardless of the milk composition. The lactose-free milks were sweet, and the low-fat milks had relatively low intensities for most flavor attributes. The electronic nose method successfully grouped the milk samples primarily based on their composition, but grouped them weakly by pasteurization method.

• Journal of Environmental Health Sciences
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• v.6 no.1
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• pp.57-63
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• 1979

A study on consecutive changes of milk was carried out to determine the changes of milk components and microorganisms by different containers. The containers included in this study were glass bottles, polyethylene packs, polystyrene bottles and aluminum foils. The number of total microorganisms and coliforms, contents of milk fat and vitamin A were tested. The results obtained were as follows: 1) The number of total microorganisms exceeded the legal criteria within 2-3 days at 4$\circ$C, 24 hours at room temperature (20-23$\circ$C) and 3 hours at 35$\circ$C. 2) The number of coliforms in milk contained in glass bottles exceeded the legal criteria within 3 days at 4$\circ$C, that of glass bottles and polyethylene packs within 12 hours at room temperature (20-23$\circ$C), that of polyethylene packs and polystyrene bottles within 6 hours at 35$\circ$C, and that of glass bottles within 9 hours at 35$\circ$C respectively. 3) The milk fat contents by di'fferent containers were not changed at all. 4) Vitamin A contents were reduced by a slight exposure to sunlight. The destruction rates of all containers were the highest in an hour after exposure to sunlight. The rates by different containers were 50.1% in glass bottles, 47.6% in polyethylene packs, 30.4% in polystyrene bottles in an hour after exposure respectively. After an hour exposure, the destruction rates gradually decreased. The vitamin A destruction rate of glass bottles were the highest, and that of polyethylene packs were next, and that of polystyrene bottles were the lowest 5) The changes of pH of milk were high in the following order: the milk in glass bottles, polyethylene packs, and polystyrene bottles. pH of milk in aluminum foils were not changed.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.4
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• pp.607-617
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• 1993

Three experiments were carried out in which lactating Hereford ${\times}$ Friesian cattle walked up to ten kilometers a day for three periods of five days with two non-walking days between each walking period and in which the animals were fed different diets. Measurements were made of milk yield, milk constituent yields and concentrations and blood metabolite concentrations. Exercise caused significant reductions in milk yield and in the yields of lactose and milk protein. Milk fat yield was not reduced when animals were exercised. During exercise the concentrations of ${\beta}-OH$ butyrate and free fatty acids increased, whereas the concentrations of glucose, magnesium and inorganic phosphorus decreased. Diet influenced the effect of exercise on some blood metabolite concentrations.