• Journal of Dairy Science and Biotechnology
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• v.17 no.1
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• pp.11-15
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• 1999

The objective of this study was to extract and purity the antibacterial agent from the fermented milk with Lactobacillus helveticus CH-1. The extraction and purification of antibacterial agent from the Lb. helveticus fermented milk were carried out by methanol extraction, acetone extraction, Sephadex G-200 gel filteration and thin layer chromatography and the results were as followings. The antibacterial activity of methanol-acetone extraction showed antibacterial activity against test organisms, B. subtilis, E. coli, Pseu. fluorescens, Sal. typhimurium, Shi. flexneri, and Sta. aureus. Sephadex G-200 gel chromatography showed only antibacterial activity from 33 to 37th fractions of 60 fractions. The agent purified from TLC plate confirmed the antibacterial activity by the means of bioautography.

• Journal of Dairy Science and Biotechnology
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• v.39 no.2
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• pp.68-77
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• 2021

This study aimed to evaluate the effects of antibacterial activity of Tibetan mushroom exopolysaccharide against foodborne pathogenic bacteria Staphylococcus aureus 305, Listeria monocytogenes ATCC19114, Escherichia coli O157:H7 ATCC42894 and Escherichia coli O55. The yield of exopolysaccharide isolated from Tibetan mushroom culture was 620 mg/L. The antibacterial activity of exopolysaccharide against foodborne pathogenic bacteria exhibited 15 mm and 12 mm clear zone against S. aureus 305 and L. monocytogenes ATCC 19114, respectively. However, no clear zone was observed against E. coli O157:H7 ATCC 42894 and E. coli O55. In conclusion, exopolysaccharide isolated from Tibetan mushroom culture have the antibacterial activity only against Gram-positive foodborne pathogenic bacteria.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1332-1339
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• 2019

Heat stress exerts a substantial effect on dairy production. The temperature and humidity index (THI) is widely used to assess heat stress in dairy operations. Herein, we review the effects of high temperature and humidity on body temperature, feed intake, milk production, follicle development, estrous behavior, and pregnancy in dairy cows. Analyses of the effects of THI on dairy production have shown that body temperature is an important physiological parameter in the evaluation of the health state of dairy cows. Although THI is an important environmental index and can help to infer the degree of heat stress, it does not reflect the physiological changes experienced by dairy cows undergoing heat stress. However, the simultaneous measurement of THI and physiological indexes (e.g., body temperature) would be very useful for improving dairy production. The successful development of automatic detection techniques makes it possible to combine THI with other physiological indexes (i.e., body temperature and activity), which could help us to comprehensively evaluate heat stress in dairy cows and provide important technical support to effectively prevent heat stress.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.895-899
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• 2002

Lysozyme activity in buffalo milk in relation to the period of lactation, parity of animal, weather conditions and udder infections was studied. Effect of storage and heat processing of milk on lysozyme activity was determined. Lysozyme activity was higher in buffalo milk than in cow milk. Buffalo colostrum showed lysozyme activity 5 times of that in mature milk. Lysozyme activity in buffalo milk was not influenced by the parity of animal and the stage of lactation, however, it increased during extreme whether conditions (winter and summer). Lysozyme in both cow and buffalo milk exhibited maximum activity at pH 7.4. Buffalo milk lysozyme was fully stable while the cow milk lysozyme was partly inactivated by pasteurization (low temperature-long time as well as high temperature-short time treatments). Lysozyme in buffalo milk was more stable than in cow milk during storage and heat treatment. A 10 to 50-fold increase in milk lysozyme activity was observed in mastitic cows. An assay of lysozyme activity in milk can be used to diagnose mastitis in cattle but not in buffaloes. Some buffaloes exhibited 1000 fold greater lysozyme activity and moderately raised somatic cell count in milk, but there was no sign of mastitis in these animals. A possible role of milk lysozyme in prevention of mastitis in buffaloes is discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1247-1254
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• 2013

The effects of Sheng Hua Tang (SHT) on uterine involution and ovarian activity were investigated in postpartum dairy cows. SHT (70 g) was given to dairy cows (n = 10) to evaluate its effects for five days from the first postpartum day. Postpartum cows fed with a basal diet without SHT were used as the control group (n = 10). Ultrasounds and blood tests were recorded for four weeks from postpartum day seven with a 3-d interval. The results showed that the areas and diameters of endometria were significantly (p<0.01) reduced in the group that received SHT compared to the control group on the seventh postpartum day. The group that received SHT had an intrauterine fluid volume mean of $1.2{\pm}0.6cm^3$, which was significantly lower than that of the control group, $2.3{\pm}0.8cm^3$ (p<0.01) on the 13th postpartum day. In addition, the uterine tension score was a mean of $1.0{\pm}0.0$ in the group that received SHT, which was also significantly lower than that of the control group, $1.5{\pm}0.5$ (p<0.01) on the 19th postpartum day. Taken together, the Chinese herbal medicine remedy, SHT, promoted uterine involution and ovarian activity in postpartum dairy cows.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.83-89
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• 2007

In our study, lactic acid bacteria (LAB)-fermented whey solutions were applied in the soybean soaking process to minimize bacterial contamination and to enrich the biologically functional components of isoflavone and $\gamma$-aminobutyric acid (GABA). Among the 11 LAB tested, Bifidobacteria infantis and a mixed culture (Lactobacillus acidophilus, Bifidobacteria lactis, and Streptococcus thermophilus; ABT-3) displaying the greatest $\beta$-glucosidase activity were selected to produce improved biologically functional soybean preparations. In the soybean soaking processing (without water spraying), the LAB-cultured 10% whey solution was used to soak and to ferment the soybeans and the fermented soybeans were finally dried by heat-blowing at $55^{\circ}C$. The processing conditions used in this study demonstrated that the final soybean product had a reduced contamination by aerobic and coliform bacteria, compared to raw soybeans, likely due to the decrease in pH during LAB fermentation. The aglycone content of the isoflavone increased up to 44.6 mg per 100 g of dried soybean by the processing method, or approximately 8-9 times as much as their initial content. The GABA contents in the processed samples increased as the processing time of soaking-fermentation proceeded as well. The soybean sample that fermented by ABT-3 culture for 24 hr showed the greatest increase in GABA content (23.95 to 97.79 mg/100 g), probably as a result of the activity of glutamate decarboxylases (GAD) released from the soybean or produced by LAB during the soaking process.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8_spc
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• pp.1306-1320
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• 2019

Goat population world-wide is increasing, and the dairy goat sector is developing accordingly. Although the new technology applied to the goat industry is being introduced slowly because the weight of traditional subsector in the dairy sector, considerable advances have been made in the last decade. Present review focuses on the emerging topics in the dairy goat sector. Research and development of traditional and new dairy goat products are reviewed, including the new research in the use of goat milk in infant formula. The research in alternatives to brine, production of skimmed goat cheeses and the use of different modified atmosphere packaging are also addressed. Special attention is given to antibiotic residues and their determination in goat milk. Functional foods for human benefits are a trending topic. Health properties recently discovered in dairy goat products are included in the paper, with special attention to the antioxidant activity. The dual-purpose use of goats by humankind is affecting the way of how new technology is being incorporated in the dairy goat sector and will certainly affect the future development of dairy goat products.

• Reproductive and Developmental Biology
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• v.33 no.3
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• pp.153-156
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• 2009

The purpose of this study was to assess for re-breeding concentrate period in postpartum in milking cows. The 48 cows aged $3.5{\sim}5.5$ years and of $400{\sim}600\;kg$ body weight were examined every 3rd day from 15 to 36 day postpartum. Blood samples for progesterone and estradiol $17{\beta}$ hormone analyses were withdrawn from the coccygeal vein every third day until the end of the experiment. The ovarian follicular numbers were verified and measured using a multi frequency probe. The least squares means are presented for each day by GLM of SAS. The results showed that ovary lengths (right ovary; $1.64{\pm}0.62\;cm$, left ovary; $1.44{\pm}0.46\;cm$) were similar in right and left ovary activity level during estrous cycle of postpartum cows. We were judged completed uterus on day at $2.31{\pm}0.17\;cm$ level of cervix diameter. And we were monitoring started at $6.44{\pm}2.03\;cm$ from day 15 after postpartum. The results showed that mean plasma concentration of progesterone (3.28 ng/ml) in large follicle gradually increased days 30 in postpartum. And, monitoring of estradiol 176 (22.18 pg/ml) hormone during postpartum period would be useful to predict the ovarian and uterus activity for re-breeding in postpartum milking cows. From these results, we conclude that cervix diameter (mean: 2.31 cm) was very important for reproductive organ recovery standard level of postpartum milking cows, hormone secretion level ($P_4$: 3.28 ng/ml, $E_2$: 22.18 pg/ml) and body condition score ($2.5{\sim}2.75$) level about 30 days in postpartum period.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.63-68
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• 2016

Rhizomes of Kaempferia parviflora (Zingiberaceae) have been used in traditional Thai medicine for health promotion. In this study, the antibacterial activity of ethanol extract of K. parviflora against Cronobacter spp. and enterohemorrhagic Escherichia coli (EHEC) was investigated using paper disc dilution method. The results revealed that the ethanol extract exhibited antibacterial activity against Cronobacter spp. and EHEC. With an increasing concentration of K. parviflora ethanol extract, larger zones of inhibition of Cronobacter spp. and EHEC strains tested were observed. Therefore, its antibacterial activity suggested that K. parviflora could be used as a natural additive to ascertain food safety of various dairy products.

• Journal of Dairy Science and Biotechnology
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• v.27 no.1
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• pp.45-51
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• 2009

$\gamma$-aminobutyric acid (GABA) is a ubiquitous nonprotein amino acid that is produced primarily by $\alpha$-decarboxylation of L-glutamic acid (Glu) catalyzed by the enzyme glutamate decarboxylase (GAD). It is well known as a neurotransmitter that regulates inhibitory neurotransmission in the mammalian central nervous system. In addition, GABA has been proved to be effective for lowering blood pressure in mammals. This paper is intended to provide basic information about GABA, including the functional and biological activity of GABA, GABA production by lactic acid bacteria, and the utilization of GABA in the production of dairy products.