• 대한수의학회지
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• 제34권1호
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• pp.189-193
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• 1994

This study was undertaken to clarify the relationship between the cause of repeat-breeder and the luteal dysfunction in repeat-breeder dairy cows that failed to conceive to three or more artificial insemination(AI) at a regular interval. Progesterone concentrations were measured in milk fat for 20 to 22 days after AI. From the 15 repeat-breeder dairy cows, six cows had a normal progesterone profiles. Five cows showed a delayed rise of the progesterone concentrations until 7 to 10 days after AI, two cows had a comparatively low concentration of milk progesterone below 150 ng/ml through most of the luteal phase, and two cows had a combined pattern of a delayed rise and a low concentration of milk progesterone during luteal phase. It is suggest that luteal dysfunction as indicated by progesterone profiles is one of the causes of repeat-breeder in dairy cows.

• 대한수의학회지
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• 제46권2호
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• pp.149-158
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• 2006

To determine the effects of ${\beta}$-carotene on the control of mastitis in dairy cows during the dry period, 38 dairy cows (18 mastitic cows and 20 healthy cows) were administered with 5 ml of ${\beta}$-carotene (30 mg/ml) intramuscularly twice (4 week intervals). Blood samples were taken from the cows before the injection and two weeks after the second injection, respectively, and were measured for the proportion of lymphocyte subpopulations and lymphocyte proliferation responses. With ${\beta}$-carotene injection, the proportion of cells expressing BoCD2, BoCD4 and B and N cells increased in healthy cows. In the presence of mitogens, lymphocytes from healthy cows showed significantly higher proliferation responses after ${\beta}$-carotene injection than before (p < 0.05), The somatic cell counts in ${\beta}$-carotene injected group decreased from 1,001,00 cells/ml at dry off to 647,000 cell/ml and 447 cells/ml at the stage of first and second weeks after calving, respectively (p < 0,05), This study indicated that ${\beta}$-carotene as a nonspecific immunostimulator could have a definite role for the prevention of intramammary infections in dairy cows at dry period.

• 대한수의학회지
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• 제59권1호
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• pp.1-8
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• 2019

We aimed to identify predictive markers of peri- and postpartum disorders in dairy cows. Data regarding peri- and postpartum disorders, serum metabolites, body condition score (BCS), and rectal temperature, were collected from 227 dairy cows, which were allocated to healthy (n = 57) and diseased (n = 170) groups. Serum non-esterified fatty acid (NEFA) concentration was higher in diseased than healthy cows 4 weeks before (p < 0.01) and immediately after (p = 0.05) calving. Serum alanine aminotransferase (AST) activity was higher (p < 0.05) in diseased than healthy cows 1 and 2 weeks after calving, whereas total cholesterol (TCH) concentration was lower (p < 0.05-0.0001) in diseased cows 4 weeks before, and after calving. BCS was higher (p < 0.05) in diseased than healthy cows 4 weeks before calving, but lower (p < 0.01) in diseased cows 8 weeks after calving. Rectal temperature was higher (p < 0.05-0.01) in diseased than healthy cows between 2 and 14 days postpartum. In conclusion, high serum NEFA and AST concentrations and lower TCH concentration during the peripartum period, and high prepartum BCS and postpartum rectal temperature, could be used as biomarkers to predict the subsequent development of peri- and postpartum disorders.

• 한국수정란이식학회지
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• 제23권3호
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• pp.141-145
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• 2008

The objective of this study was to investigate the relationship between behavioral signs and duration of estrous in Hanwoo and Holstein cattle for the prediction of optical insemination. Fifty two of 58 and 71 of 89 in Hanwoo and Holstein cows or heifers showed estrous exhibition within 72 h after 2 days following $PGF_{2}\alpha$ administration, respectively. The number of mounting and standing heat were 54.2 and 57.6, 59.4 and 53.5, 42.0 and 30.8 and 16.2 and 10.7 times in Hanwoo cows, Hanwoo heifers, Holstein cows and Holstein heifers, respectively. Duration of mounting were no significantly difference for Hanwoo cows ($21.2\pm11.3$), Hanwoo heifers ($19.9\pm11.4$), Holstein cows ($8.7\pm4.4$) and Holstein heifers ($16.9\pm8.0$). Duration of standing heat were significantly (p<0.05) shorter for Holstein cows ($5.4\pm3.4$) than for Hanwoo cows ($17.1\pm9.6$), Hanwoo heifers ($16.5\pm6.3$) and Holstein heifers ($15.0\pm7.2$). Time until mounting after injection of $PGF_{2}\alpha$ were significantly (p<0.05) longer for Holstein cows ($56.3\pm11.45$) than for Hanwoo cows ($42.71\pm10.44$), Hanwoo heifers ($36.6\pm8.21$) and Holstein heifers ($40.70\pm6.15$). Time until standing heat after injection of $PGF_{2}\alpha$ were significantly (p<0.05) longer for Holstein cows ($61.6\pm8.92$) than for Hanwoo cows ($46.2\pm11.49$), Hanwoo heifers ($42.7\pm6.06$) and Holstein heifers ($44.1\pm6.72$). In the results of this study, duration of standing heat was the shortest in Holstein cows ($5.4\pm3.4$). The estimation of estrous with Holstein cows has more difficulty because to significantly shorter duration of standing heat than for Hanwoo cows, Hanwoo heifers and Holstein heifers. The standing heat can be a good predictor for time of ovulation but it is concluded that mounting behavior could be the best predictor for time of ovulation.

• 한국임상수의학회지
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• 제27권4호
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• pp.397-401
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• 2010

This study was to evaluate the usefulness of a programmed reproductive management including Presynch-Ovsynch-Resynch protocol in lactating dairy cows. Nine hundred and thirty four cows calved during February to May 2008 were used for this study. Cows received im injections of 25 mg $PGF_{2{\alpha}}$ at $45{\pm}3$ and $59{\pm}3$ days in milk (DIM). Fourteen days later, Ovsynch was initiated with an im injection of $100\;{\mu}g$ GnRH ($73{\pm}3$ DIM), 25 mg $PGF_{2{\alpha}}$ 7 days later ($80{\pm}3$ DIM), $100\;{\mu}g$ GnRH 56 h later and timed artificial insemination (TAI) 16 h after the GnRH injection. Cows showed estrus during the Presynch-Ovsynch, were inseminated artificially according to am-pm rule. Pregnancy was determined on 32 days after AI using ultrasonography. Cows diagnosed pregnant were re-examined for pregnancy by rectal palpation at 60 days after AI. Non-pregnant cows were resynchronized by receiving $100\;{\mu}g$ GnRH, 25 mg $PGF_{2{\alpha}}$ 7 days later, $100\;{\mu}g$ GnRH 56 h later and TAI 16 h after. Cows with estrus since the first AI before the completion of Resynch protocol were also inseminated artificially according to am-pm rule. Pregnancy was determined by the same manner as following the first AI. Fifty five percents of the cows treated showed estrus and received AI before completion of the Presynch-Ovsynch protocol, while 45% received TAI, regardless of estrus exhibition following the completion of the protocol. The pregnancy rate following the first AI was higher in cows that showed estrus and received AI (43.3 and 38.5%) during the Presynch-Ovsynch than cows with TAI (34.6 and 29.6%) on 32 and 60 days after AI (P < 0.01). Sixty six percents of cows diagnosed non-pregnant following the first AI showed estrus before the completion of Resynch protocol and received AI, while 34% received TAI, regardless of estrus exhibition following the completion of the protocol. The pregnancy rate following the second AI was higher in cows that showed estrus before the completion of Resynch protocol and received AI (40.2 and 36.8%) than cows with TAI (21.2 and 18.2%) on 32 and 60 days after AI (P < 0.01). The cumulative pregnancy rates following the first and second AIs were 60.8 and 53.9% on 32 and 60 days after AI, respectively. These data suggest that inclusion of Presynch-Ovsynch-Resynch protocol and estrus detection into the programmed reproductive management might be an alternative option to control dairy cattle breeding.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1735-1740
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• 2005

Forty-two single-bearing and 42 twin-bearing mature Angus${\times}$Hereford cows were allocated, seven per cell to 3 replications of 2 stocking rates (3.2 cows/ha; medium stocking rate [MSR], and 3.8 cows/ha; high stocking rate [HSR]) to graze summer-active and winter-active pastures from late pregnancy to the weaning of their calves. Cow liveweights and growth of calves were recorded as well as estimates of pasture quantity and forage intake. Pasture quantity did not differ in the paddocks grazed by single- and twin-bearing cows during pregnancy, nor effectively did forage intake. Subsequently, intake was higher during mid-lactation especially with twin-rearing cows (25% higher than single-rearing cows at the MSR; 9% at the HSR). However, quantity of pasture decreased for twin-rearing cows and was less than that available to single-rearing cows as lactation progressed. Liveweights of twinrearing cows decreased by 16% from late pregnancy to weaning at the MSR, and by 14% at the HSR, compared to decreases of 1% for single-rearing cows. Twin calves were lighter at birth, had slower growth rates, and were lighter at weaning than single calves. In spite of weaning smaller calves twinning increased the output (kg of calf weaned) per cow and per ha, and increased the efficiency (kg calf weaned per unit of forage eaten by the cow) over single calf production by 46% at the MSR and by 58% at the HSR. Twinning also increased the marginal returns from investment in high input pastures required by the enterprise.

• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.240-244
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• 1997

This study was conducted in North Sulawesi, Indonesia to identify the factors affecting reproductive efficiency and to determine the contribution of each factor in reproductive efficiency of Indonesian native cows. Records of reproductive efficiency, body size (hip height, body weight, body length, heart girth) as well as age on one hundred and sixty seven Indonesian native cows (seventy six cows of the Bali breed and ninety one cows of the synthetic breed from unknown proportion of th Madura, the Sumba and the Ongole breeds) of 58 farmers were available in this research. The data were analyzed by covariance analysis using SAS package including reproductive efficiency as a dependent variable and breed, body size (hip height, body weight, body length, heart girth) and age of cows as independent variables. The contribution of each independent factor to dependent variable was estimated as the percentage of the sum of square in the corrected total sum of squares. The results showed that body weight and body size of cows would be considered as th most important factors affecting reproductive efficiency of Indonesian native cows. Therefore, the reproductive efficiency could be increased by 1) using cows that reached a target weight of at least 250 kg, 2) using cows with relatively well developed height at hip of at least 117 cm, heart girth of at least 150 cm, and body length of at least 125 cm, 3) keeping breeding cows that reach a target age of 24 months old with the maximum interval between postpartum and next breeding season of 90 days for each year, and 4) using good nutritional feeding to reach the optimum weight and body condition.

• Asian-Australasian Journal of Animal Sciences
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• 제21권4호
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• pp.555-560
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• 2008

The effects of utilizing evaporative cooling system equipped with tunnel ventilation on postpartum ovarian activities, energy balance and milk production of early lactating dairy cows under hot and humid climates were studied from parturition to 22 wk postpartum. Thirty-four crossbred Holstein-Friesian (93.75% HF$\times$.25% Bos indicus) primiparous cows were randomly assigned to one of two groups. Cooled cows (n = 17; treatment) were housed in the tunnel ventilated barn equipped with evaporative cooling system and uncooled (n = 17; control) were housed in the naturally ventilated barn without supplemental cooling system. Cooled cows had greater (p<0.05) dry matter intake and milk production than uncooled cows. Days to the energy balance (EB) nadir did not differ between groups. However, days to equilibrium EB for uncooled cows was longer (p<0.05) than for cooled cows. There was no significant difference in postpartum anovular condition between cooled and uncooled cows. The interval from parturition to first postpartum ovulation did not differ between groups ($31.4{\pm}4.3$ and $26.1{\pm}3.6$ day, respectively). These results suggest that the evaporative cooling and tunnel ventilation has the potential to decrease the severity of heat stress and improve both milk production and metabolic efficiency during early lactation without affecting reproductive function in dairy cows under hot and humid climates.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.359-367
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• 2003

Supplementary feeding strategies were evaluated from pre-calving throughout lactation on 24 dual-purpose Mpwapwa breed cows in their second or greater lactation, weighing 246-455 kg. The Mpwapwa breed is an established breed of 4 Bos indicus breeds and 8% of Bos taurus. The cows were penned and stall-fed individually. Eight weeks before calving to eight weeks after calving, the cows were divided into two groups and offered hay ad libitum with either 2 kg DM (L) or 4 kg DM/day (H) concentrates. Nine weeks after calving half of the cows on L-level continued with 2 kg DM/day (L-L) while the remainder received 4 kg DM concentrate daily (L-H). Half of the cows on H-group continued with 4 kg DM/day (H-H) while the remainder received 2 kg DM/day (H-L). The concentrate mixture comprised of sunflower seed cake (33%) and maize bran (67%). The cows consumed all the concentrate offered. Hay DM intake was similar (6.8 kg/day) and tended to decrease the last two weeks before calving increased again after calving. Live weight change and body condition score were similar across treatments before calving but differed after calving (p<0.05). Heavier cows with higher condition score pre-calving had a higher body weight loss and regained weight later. After treatment reallocation, live weight change and condition differed between treatments (p<0.05). Calves were allowed to suckle milk from one quarter. The amount of milk suckled and calf weight gains were not significantly different between treatments. The cows were removed from the experiment when the milk yield was below 4 kg per day. Cows on treatment H produced 6.2 kg and on treatment L 5.0 kg saleable milk/day (p<0.05) during the first 8 weeks post partum. During the period 9-18 weeks post partum the saleable daily milk on H-H, L-H, H-L and L-L were 5.2, 4.8, 4.7 and 4.3 kg, respectively (p>0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제27권3호
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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.