• Journal of Environmental Health Sciences
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• v.11 no.2
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• pp.41-54
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• 1985

This study was conducted for the improvement of milk quality and milk hygiene in public health point of view. Investigation of mastiris infection rate, isolation and identification of causative microorganisms in CMT positive milk, investigation of milk contamination level by measuring the bacteria and soma tic cell counts and investigation of dairy management in farms were performed on 1.605 quarters milk of 434 cows of 20 dairy farms in Gyunggi-area from September 1983 to March 1984. The results were summarized as follows 1. Sixteen (3.7%) of 434 cows were found to be infected with clinical mastiris. 234 (53.9%) of 434 cows and 608(37.9%) of 1, 605 quarters were found to be infected with subclinical mastiris. 2. The causative microorganisms isolated were Staphylococcus aureus (38.3%), Staphylococcus epidermidis(21.0%), Micrococci(13.6%), Streptococcus spp. (12.3%), E. coli (7.4%), Fungus & Yeast (1.6%) and others (5.8%). 3. Total numbers of bacteria were $9.2{\times}10^6$ to $1.21{\times}10^7/ml$(av. $1.805{\times} 10^7/ml$), numbers of coliform bacteria were $4.1{\times} 10^5$ to $9.4{\times} 10^5$/ml(av. $7.05{\times} 10^5$/ml) and somatic cell counts were $4.8{\times} 10^5$ to $1.52{\times} 10^6$ cells/ml (av. $9.5{\times} 10^5$cells/ml) in bulk milk. 4. As comparing with CMT score of +, ++ and +++, somatic cell counts were $3.4{\times} 10^5$ to $1.64{\times} 10^6$ cells/ml (av. $6.41{\times} 10^5$cells/ml), $5.4{\times} 10^5$ to $2.75{\times} 10^6$ cells/ml(av. $1.762{\times} 10^6$cells/ml) and $1.97{\times} 10^6$ to $9.75{\times} 10^6$ cells/ml(av. $7.781{\times} 10^6$cells/ml), respectively. 5. In investigation on dairy management, performance of dry cow therapy, teat dipping after milking, disinfection of milking machine at every milking, replacement of milk liner within 6months and opportunity of acquirement for the mastiris control techniques by dairy education were 65%, 40%, 45%, 55% and 50% in 20 dairy farms, respectively.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.687-693
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• 2015

Using 378,086 lactation records on dairy cattle, environmental factors influencing acetone and ${\beta}$-hydroxybutyrate acid contents in raw milk which are used as ketosis diagnosis indicator traits were analyzed in this experiment. Significance testing was conducted on farm, lactation stage, parity, milking time and month of age by traits. The results of this experiment indicated that there was a highly significant (p < 0.01) difference in all factors and lactation stage was the most significant factor. Linear regression coefficients of month of age on daily milk yields and acetone and ${\beta}$-hydroxybutyrate acid contents were all positive, while their quadratic linear regression coefficients were negative. Least square means for milk yield at second lactation stage (36~65 days) was 19.06kg which was higher than that of late lactation stage by 6.51kg. Least square means for acetone and ${\beta}$-hydroxybutyrate acid contents at the first lactation stage (5~35 days) were highest (0.1929mM/L and 0.0742mM/L, respectively), and there was a trend that they decreased as the milking progressed, but increased slightly at the late stage of milking. However, least square means for acetone and ${\beta}$-hydroxybutyrate acid contents at the first parity were 0.1414mM/L and 0.0522mM/L, respectively, which were higher than the average milk yield after the second parity. Least square means for acetone and ${\beta}$-hydroxybutyrate acid contents of PM milk yield (0.1372mM/L and 0.0534mM/L, respectively) were higher than those of AM milk yield collectively.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.957-962
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• 2002

In July, three trials were conducted to evaluate the best sponge type and optimum PMSG dose to be administered to sheep under the Jordanian Badia (arid) conditions. In trial 1, three flocks (n=77, n=18 and n=47 for flocks 1, 2 and 3, respectively) were administered with 40 mg fluorogestone acetate (FGA) intravaginal sponges for 12 days before receiving 600 IU of PMSG at the time of sponge removal. In trial 2, 95 ewes were assigned to 4 groups to receive 300 (n=25), 450 (n=27), 600 (n=22) or 750 (n=21) IU of PMSG following a 12 d FGA 40 mg sponge insertion period. In trial 3, 60 ewes were assigned to 3 groups (n=20) to receive either FGA 30 mg, FGA 40 mg or medroxyprogesterone acetate (MAP) 60 mg intravaginal sponges all followed by an administration of 600 IU of PMSG at sponge removal. In all trials, rams were isolated 1 day before sponge insertion and were allowed back with the ewes at sponge removal. Estrual responses and lambing data were collected. The effects of treatment, milking status and face color on estrual responses and lambing data were examined. In trial 1, greater first cycle conception rate (p<0.05), twinning rate (p<0.01) and the number of lambs born/served ewe (p<0.01) were observed in flock 2 compared with flocks 1 and 3. Neither face color nor milking status had any influence on the measured parameters (p>0.05). Despite low lambing rate in trial 2, ewes receiving 600 IU of PMSG had greater (p<0.05) number of lambs born/served ewe compared with ewes receiving 450 IU of PMSG. Regardless of PMSG dose, intervals to detected estrus occurred 10 h earlier (p<0.01) in dry than lactating ewes. Similar to trial 2, lambing rate was depressed in trial 3. The expression of estrus was advanced (p<0.05) in ewes receiving MAP 60 mg sponges compared with those receiving FGA 30 and FGA 40 mg sponges (42$\pm$3.1, 49$\pm$3.1 and 49$\pm$3.1 h post sponge removal in ewes receiving MAP 60 mg, FGA 30 mg and FGA 40 mg sponges, respectively). Other parameters were not influenced (p>0.05) by sponge type, milking status and face color. Data show that a 600 IU dose of PMSG tends to give the best lambing results. In addition, results indicate that the use 60 mg MAP sponges for estrus synchronization may be more appropriate under the Jordanian Badia conditions during late seasonal anestrus.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.6
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• pp.896-902
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• 2015

Milking center wastewater (MCW) has a relatively low ratio of carbon to nitrogen (C/N ratio), which should be separately managed from livestock manure due to the negative impacts of manure nutrients and harmful effects on down-stream in the livestock manure process with respect to the microbial growth. Simultaneous nitrification and denitrification (SND) is linked to inhibition of the second nitrification and reduces around 40% of the carbonaceous energy available for denitrification. Thus, this study was conducted to find the optimal operational conditions for the treatment of MCW using an attached-growth biofilm reactor; i.e., nitrogen loading rate (NLR) of 0.14, 0.28, 0.43, and $0.58kg\;m^{-3}\;d^{-1}$ and aeration rate of 0.06, 0.12, and $0.24\;m^3\;h^{-1}$ were evaluated and the comparison of air-diffuser position between one-third and bottom of the reactor was conducted. Four sand packed-bed reactors with the effective volume of 2.5 L were prepared and initially an air-diffuser was placed at one third from the bottom of the reactor. After the adaptation period of 2 weeks, SND was observed at all four reactors and the optimal NLR of $0.45kg\;m^{-3}\;d^{-1}$ was found as a threshold value to obtain higher nitrogen removal efficiency. Dissolved oxygen (DO) as one of key operational conditions was measured during the experiment and the reactor with an aeration rate of $0.12\;m^3\;h^{-1}$ showed the best performance of $NH_4-N$ removal and the higher total nitrogen removal efficiency through SND with appropriate DO level of ${\sim}0.5\;mg\;DO\;L^{-1}$. The air-diffuser position at one third from the bottom of the reactor resulted in better nitrogen removal than at the bottom position. Consequently, nitrogen in MCW with a low C/N ratio of 2.15 was successfully removed without the addition of external carbon sources.

• Journal of Animal Environmental Science
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• v.17 no.2
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• pp.93-100
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• 2011

This study was conducted to verify the applicability of robot milking system through acquisition and analysis of model teat's position information using scanning range finder (SRF). Model teats, same size and shape as real teats, were designed to analyze the properties according to the material, distance error and angle error of the sensor. In addition, 2-dimensional distance information of each teats was obtained at same time with 4 teat models and the result were as follows. 1. In the case of the fingers on the experiment for selection of materials for teat model, the distance error was from 4.3 mm to 1.3 mm, average was 2.8 mm as a minimum record. In the case of rubber material, average distance error was 4.3 mm. So, this material was considered to be a most suitable model. 2. The distance error was maximum at 100 mm distance. The more distance increased, the less error increased up to 300 mm. Then the error increased after 300 mm and decreased again. 3. The maximum angle error of 10.1 mm was measured at $170^{\circ}$, in case of $70^{\circ}$ the error was 0.2 mm as a minimum value. There was no specific tendency to error of angle. 4. In the 2-dimensional location error for 4 teat models, distance error was 3.8 mm as minimum and 7.2 mm as maximum. The angle error was $1.2^{\circ}$ as maximum. All of errors were included within the accuracy of sensor, the robot milking system was considered to be applicable to measure the distance of teats due to the measuring velocity of SRF and the hole size of teat-cup.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.49-55
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• 1984

This study was carried out to investigate the biological performance of the brownplanthopper, Nilaparvata lugens Stal, reared on rice plants at different growth stages; maximum tillering, booting, heading with and without panicles, and milking. The results obtained are as follows: The rice plants at the maximum tillering stage gave the best in the longevity, oviposition period, and the total number of oviposited eggs for the macropterous females, and the worst with the booting stage. For the brachypterous females, however, the best results were obtained from the rice of which their panicles had removed after heading. There was no significant difference in the hachability of eggs and the developmental period of the nymphs in the next generation, but the nymphal mortality was the highest with the milking stage and the lowest with the maximum tillering and heading stage without panicles. The longest life span was shown in males derived on the maximum tillering stage, and the shortest for milking(macropterous type) or booting (brachypterous type) stages. Coefficientes of variances in longevity and number of eggs for the adults emerged from heading stage without panicles were lower than those with panicles intact, and such trend was more obvious in brachypterous adults, especially for the females. The biological performances of the BPH have close relationship with the translocated organic material at the feeding site which showed considerable difference with the growth stages of the rice.

• Journal of Dairy Science and Biotechnology
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• v.34 no.1
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• pp.37-41
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• 2016

Melatonin is a hormone produced by the pineal gland in dark conditions. It plays a major role in the regulation of the sleep-wake cycle. Melatonin synthesis is known to be suppressed by environmental light. Cortisol is a steroid hormone that is a major indicator of physiological alterations due to stressful stimuli. It also displays a circadian rhythm, like melatonin. The highest levels are encountered during early morning and the lowest levels are observed at around midnight. In the present study, the effects of milking time on the melatonin and cortisol concentrations of raw milk and milk powder at the summer and winter solstices were examined. The melatonin concentration in milk increased significantly if cows were milked in the dark at night (p<0.05). The melatonin concentration in milk powder showed the same pattern with respect to the milking time (p<0.05). However, no significant difference in the cortisol concentration was observed between day- and night-time milk. Although the time of day did not affect the level of milk cortisol, seasonal factors affected the release of cortisol in milk (p<0.05). In conclusion, night-time milk is rich in endogenous melatonin. In this respect, it has potential applications for the development of melatonin rich-dairy products, which serve as natural sources of melatonin.

• Journal of Animal Science and Technology
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• v.63 no.3
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• pp.626-639
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• 2021

The purpose of this study was to determine the effects of photoperiod and light intensity on milk production, milk composition, hormones levels and blood metabolites indices of Korean Holstein dairy cows in automatic milking system (AMS). A total of 24 Holstein dairy cows were selected and used to four subsequent treatments for the experimental periods of 60 days. The light programs consisted of (1) Control: the natural photoperiod with 14.2 h of the light period and 9.4 h of the dark period (below 10 Lux); (2) T1: 16 h of the long day photoperiod (LDPP) with 50 Lux of light; (3) T2: 16 h of LDPP with 100 Lux of light; and (4) T3: 16 h of LDPP with 200 Lux of light, respectively. Importantly, there was a significant difference in the thurl activity of dairy cows between the different light intensity programs (p < 0.05). Milk yield was higher in T1 and T2 (40.80 ± 1.71 and 39.90 ± 2.02 kg/d, respectively) than those of Control and T3 (32.18 ± 1.51 and 35.76 ± 2.80 kg/d, respectively) (p < 0.05), but DMI was lower in T1, T2, and T3 compared to Control (p < 0.05). Also, milk fat percentage, the contents of milk fat and total solids were higher in T2 than those in the others (p < 0.05). The average daily melatonin level in milk was high to T3 (28.20 ± 0.43 pg/mL), T2 (24.62 ± 0.32 pg/mL), T1 (19.78 ± 0.35 pg/mL), and Control (19.36 ± 0.45 pg/mL) in order (p < 0.05). Also, the cortisol levels in milk and blood were lower in treatment groups than in Control (p < 0.05). The results of this study showed that it will be effective to improve the milk yield and milk composition, and to reduce the stress of dairy cows when the light conditions regulate to extend the photoperiod to 16 h at a light emitting diode (LED) intensity of 100 Lux under the AMS in dairy farm.

• Animal Bioscience
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• v.37 no.2
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• pp.173-183
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• 2024

Objective: This study aimed to evaluate whether the methane (CH₄) to carbon dioxide (CO₂) ratio (CH₄/CO₂) and methane-related traits obtained by the sniffer method can be used as indicators for genetic selection of Holstein cows with lower CH₄ emissions. Methods: The sniffer method was used to simultaneously measure the concentrations of CH₄ and CO₂ during milking in each milking box of the automatic milking system to obtain CH₄/CO₂. Methane-related traits, which included CH₄ emissions, CH₄ per energy-corrected milk, methane conversion factor (MCF), and residual CH₄, were calculated. First, we investigated the impact of the model with and without body weight (BW) on the lactation stage and parity for predicting methane-related traits using a first on-farm dataset (Farm 1; 400 records for 74 Holstein cows). Second, we estimated the genetic parameters for CH₄/CO₂ and methane-related traits using a second on-farm dataset (Farm 2; 520 records for 182 Holstein cows). Third, we compared the repeatability and environmental effects on these traits in both farm datasets. Results: The data from Farm 1 revealed that MCF can be reliably evaluated during the lactation stage and parity, even when BW is excluded from the model. Farm 2 data revealed low heritability and moderate repeatability for CH₄/CO₂ (0.12 and 0.46, respectively) and MCF (0.13 and 0.38, respectively). In addition, the estimated genetic correlation of milk yield with CH₄/CO₂ was low (0.07) and that with MCF was moderate (-0.53). The on-farm data indicated that CH₄/CO₂ and MCF could be evaluated consistently during the lactation stage and parity with moderate repeatability on both farms. Conclusion: This study demonstrated the on-farm applicability of the sniffer method for selecting cows with low CH₄ emissions.

• Journal of the korean veterinary medical association
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• v.37 no.10
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• pp.949-954
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• 2001

착유효과는 시간 당 소에 대한 일정한 일을 주로 측정하는 것이다. 그러나 시간 당 착유우유 kg에서 일정한 일의 양 또는 시간 당 더 좋은 우유 kg까지가 바라는 것이다. 소/시간에 대한 초점은 착유 전 유두준비에 소비시간을 감소 시키는 것이다. 그리고 이 검토는 우유생산, 안정된 우유흐름에 대한 시간, 유질과 유방건강에 중점을 둔 것이다. 우유의 질이나 유방염에 대하여 착유준비는 대단히 중요하다. 우리는 권장된 기준에 맞추어 착유준비를 하고 있는가? 스스로 검토하여 보아야 한다. 또한 그 기준에 정확히 따라서 함은 물론이고, 필요한 기구와 약제의 사용에도 하자가 없는지 재 확인하여 보아야 한다 그렇지 안으면 자기의 책임을 다른 곳에 돌리고 실제작업의 교정에는 실패를 하는 경우가 될 것이다.