• 제목/요약/키워드: Dry period length

검색결과 180건 처리시간 0.03초

Effects of dry period length on milk production and physiological responses of heat-stressed dairy cows during the transition period

  • Dong-Hyun Lim;Da Jin Sol Jung;Kwang-Seok Ki;Dong-Hyeon Kim;Manhye Han;Younghoon Kim
    • Journal of Animal Science and Technology
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    • 제65권1호
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    • pp.197-208
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    • 2023
  • The objective of this study was to investigate the effects of a traditional dry period (60 d) versus a no dry period (0 d) on the milk production, physiological response, and metabolic status of dairy cows exposed to heat stress during the transition period. Holstein dairy cows (n = 15) with similar expected calving dates were randomly assigned to two different dry period lengths: (1) no dry period (n = 7) and (2) a traditional dry period of 60 days (n = 8). All cows were studied from 8 weeks before expected calving to 10 weeks after calving and experienced heat stress during the transition period. The results showed that cows with no dry period decreased their milk yield in subsequent lactation, but compensated for the loss of milk yield accounted for by additional milk yield before calving. The energy balance at postpartum was improved in cows with no dry period compared to cows with a traditional dry period. There were no significant differences in the physiological response and blood metabolites at postpartum between the dry period lengths of dairy cows exposed to heat stress during the transition period. Taken together, our results showed that omitting the dry period improved the milk production and metabolic status of dairy cows exposed to heat stress during the transition period.

Prepartum Feeding of Cationic or Anionic Diets to Holstein Cows Given 30 or 60 Day Dry Periods: Comparison of Dry Matter Intake, Physiological Measures and Milk Production

  • Gulay, M.S.;Hayen, M.J.;Bachman, K.C.;Head, H.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권1호
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    • pp.83-89
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    • 2008
  • Eighty-four Holstein cows were used to evaluate effects of feeding two diets that differed in dietary cation-anion difference (cationic; +28 or anionic; -138 mEq/kg DM) on prepartum and postpartum dry matter intake (DMI), body weight (BW), body condition score (BCS), serum Ca concentrations and on subsequent milk production and composition. Treatments were in a $2{\times}3{\times}2$ factorial arrangement that included prepartum diet, dry period length (30 d dry, 30 d dry+estradiol cypionate (ECP), and 60 d dry), and prepartum and postpartum bST ($POSILAC^{(R)}$ 10.2 mg/d). No interaction of prepartum diet with dry period length or bST supplementation was detected for any measure evaluated either prepartum or postpartum. No significant effects of prepartum diet on prepartum DMI, BW or BCS were observed. Mean DMI during the first 28 d postpartum were similar for cows fed the cationic or anionic diets prepartum (25.5 vs. 26.1 kg/d). During postpartum wk 1 to 14, no differences in mean BW or BCS were detected due to prepartum diet fed but decreases for both groups were observed during the first 6 wk postpartum. No differences due to prepartum diet were observed for mean milk or 3.5% FCM yields or for milk composition during the first 10 wk of lactation. Similarly, mean milk yield of cows during the first 21 wk did not differ significantly due to prepartum diet fed (38.5 vs. 38.6 kg/d). Overall, cows fed the prepartum cationic or anionic diets had similar mean postpartum serum concentrations of Ca (9.34 vs. 9.35 mg/dl). Subsequent milk production, milk composition and concentrations of Ca did not differ. Importantly, the two prepartum diets were equally satisfactory in minimizing incidence of milk fever and in supporting initiation of lactation, irrespective of dry period length and supplemental ECP and bST.

Improving Productive and Reproductive Performance of Holstein Dairy Cows through Dry Period Management

  • Safa, S.;Soleimani, A.;Heravi Moussavi, A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권5호
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    • pp.630-637
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    • 2013
  • To determine the effects of dry period (DP) length on milk yield, milk composition, some blood metabolites, complete blood count (CBC), body weight and score and follicular status, twenty five primiparous and multiparous Holstein cows were assigned to a completely randomized design with DP-60 (n = 13) and DP-20 (n = 12) dry period lengths. Cows in the DP-60 produced more milk, protein, SNF, serum non-esterified fatty acids (NEFA) and beta hydroxyl butyrate acid (BHBA) compared with cows in DP-20 ($p{\leq}0.05$). Serum glucose, blood urea nitrogen (BUN), urea, and glutamic oxaloacetic transaminase (GOT) were all similar among the treatments. Body Condition Score (BCS), body weight (BW), complete blood count (CBC) and health problems were similar between the treatments. Diameter of the first dominant follicle and diameter of the dominant follicle on d 14 were different among the treatments. Thus, results of this study showed that reducing the dry period length to DP-20 had a negative effect on milk production, milk composition and reproductive performance in Holstein dairy cows.

육묘포트 깊이가 담배의 뿌리발달 및 분포에 미치는 영향 (Effect of Pot Depth on Root Development and Distribution during Seedling Growing Period in Tobacco.)

  • 이상각;심상인;강병화;이학수;석영선
    • 한국연초학회지
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    • 제19권1호
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    • pp.18-23
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    • 1997
  • The study was carried out to clarify reasonable production of healthy seedling, optimal Pot depth, and appropriate transplanting time, which can be deduced from understanding of seedling quality. Seedling quality results from growth of root and shoot, morphology and distribution of root system under influence of Pot depth during seedling growing period. Stem height, shoot dry weight, leaf area and leaf number were increased in proportion to depth of pots. Growth of shoot and root during seedling growing period showed the most dramatic development between 20th and 25th day after temporary planting. Root number increased as pot depth decrease and total root length and dry weight increased as pot depth increase. In 5cm pot, relative multiplication rate was higher and mean extension rate was lower than other depth of Pot. The limitation of pot volume in which rhizosphere was located enhance the development of roots of second and third order. At 20th days after temporary Planting root distribution was relatively uniform in length and development of adventitious root on stem base was poor as Pot depth decreased.

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관측자료로 추정한 강우유출모형을 기후변화 영향평가에 그대로 활용하여도 되는가? (Is it suitable to Use Rainfall Runoff Model with Observed Data for Climate Change Impact Assessment?)

  • 니로저 뽀우델;김영오;김초롱
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2011년도 학술발표회
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    • pp.252-252
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    • 2011
  • Rainfall-runoff models are calibrated and validated by using a same data set such as observations. The past climate change effects the present rainfall pattern and also will effect on the future. To predict rainfall-runoff more preciously we have to consider the climate change pattern in the past, present and the future time. Thus, in this study, the climate change represents changes in mean precipitation and standard deviation in different patterns. In some river basins, there is no enough length of data for the analysis. Therefore, we have to generate the synthetic data using proper distribution for calculation of precipitation based on the observed data. In this study, Kajiyama model is used to analyze the runoff in the dry and the wet period, separately. Mean and standard deviation are used for generating precipitation from the gamma distribution. Twenty hypothetical scenarios are considered to show the climate change conditions. The mean precipitation are changed by -20%, -10%, 0%, +10% and +20% for the data generation with keeping the standard deviation constant in the wet and the dry period respectively. Similarly, the standard deviations of precipitation are changed by -20%, -10%, 0%, +10% and +20% keeping the mean value of precipitation constant for the wet and the dry period sequentially. In the wet period, when the standard deviation value varies then the mean NSE ratio is more fluctuate rather than the dry period. On the other hand, the mean NSE ratio in some extent is more fluctuate in the wet period and sometimes in the dry period, if the mean value of precipitation varies while keeping the standard deviation constant.

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무강수일수와 강우효과를 고려한 개선된 표준강수지수 개발 (Development of a Modified Standardized Precipitation Index by Considering Effects of the Dry Period and Rainfall)

  • 이준원;김광섭
    • 한국수자원학회논문집
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    • 제45권4호
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    • pp.409-418
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    • 2012
  • 본 연구에서는 가뭄의 심도에 직접적으로 영향을 주는 무강수일수를 고려하고, 강수에서 기인하는 지표면유출 효과를 반영한 가뭄해갈에 유효한 강수를 산정하여 기존의 SPI3을 개선한 Modified SPI를 제시하였다. 1973년부터 2009년까지 각종 보고서 및 문헌자료를 통해 실제 발생한 가뭄사례를 수집하여 행정구역별 가뭄공간정보를 생산하고, 동일기간 전국 69개지점에서산정된 가뭄지수를 우리나라 전체 공간으로표현하여각종 지수의 적합성을 평가하기 위하여ROC 분석을 수행하였다. 개선된 가뭄지수 제시를 위하여 총 강우량 중단기적인 유출에 기여할 것으로 판단되는 부분을 절삭하여 유효강우를 산정하였으며, 월단위의 무강수일수를 십분위, 누적분포함수로 변형하여 기존의 지수에 가중치를 부여하였다. 분석결과 유출량을 고려한 강우의 절삭은 기존의 SPI3에 비하여 상대적으로 높은 가뭄감지능력을 보여주었으며, 무강수일수를 고려한 가뭄지수의 개선은 누적분포함수의 수치를 고려함으로서 상당히 개선된 가뭄감지 능력을 보여주었다.

잎담배의 재배방법에 따른 생장 분석에 대하여 (The Growth-Curve Analysis of Tobacco in Various Cultivation Types)

  • 김윤동;김용암
    • 한국연초학회지
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    • 제2권2호
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    • pp.44-50
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    • 1980
  • 황색종 잎담배의 생장분석에서 얻어진 결과는 다음과 같다. 1. 개량말칭의 생장곡선은 대수변환하여 2차 회귀식에, 기타 작부는 Gomuertz방정식과 유사하였다. 2. 건물량에 있어서 최대생장기의 시점은 개량말칭의 경우에 이식후 50일경, 타 작부는40일경이고 최대생장기간은 모두 25일 였다. 3 건물량에 있어서 최대생장기의 생장속도는 개량, 일반, 나지작의 순서로 감소하였다. 4. 파기가 늦을수록 최대생장기 동안의 생장량은 증가했다. 5. 엽면적의 최대생장기간은 건물중에 비하여 약2일 단축되고 5일 정도 빠르게 나타났다.

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파종기 및 육묘기간이 단작택사의 생육 및 수량에 미치는 영향 (Influence of Sowing Dates and Nursery Period on Growth and Yield of Alisma plantago L. in Mono Cropping)

  • 장영석;최달호;권병선;신종섭
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2000년도 춘계임시총회 및 학술발표대회
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    • pp.38-44
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    • 2000
  • To determine the optimum sowing date and nursery period in Alisma piantago in the southern area of Korea, Alisma plantago local cultivar was grown under three different sowing dates and nursery periods. The plant height, leaf width and leaf length at the area sown on the seedbed in June 30 and conducted the growing seedling in 30 days is 12.1cm, 2.5cm and 3.1cm respectively and it shows tess decrease than that of plant height, leaf width and leaf length with 12.3cm, 2.6cm and 3.2cm respectively which was sown on the seedbed in June 20 and carried out the growing seedling in 30 days, and it also shows less decrease than that of plant height, leaf width and leaf length with 15.2cm, 3.1cm and 5.2cm respectively at the area sown on the seedbed in July 10 and condected the growing seedling in the same date. The stem length, number of stems and diameter of root at the area sown on the seedbed in June 30 and conducted the growing seedling in 30 days is 31cm, 11 and 3.7cm respectively and it shows more increase than that of stem length, number of stem and diameter of and on the other hand shows tess decrease than that of stem length, number of stems and diameter of root with 30cm, 10cm, 35cm respectively which was sown on the seedbed in 30 days, and on the other hand shows less decrease than that of stem length, number of stems and diameter of root with 32cm,13cm,3.9cm respectively at the area sown on the seedbed in July 10 and conducted the growing seedling in the same date, The fresh yield of roots at the area sown on the seedbed in June 30 and conducted the growing seedling in 30 days is 431.4Kg/10a and it shows more increase of 26.9Kg than that of fresh yield of root with 410.59g110a which was sown on the seedbed in lune 20an4 carried out the growing seedling in 30 days, and it also shows more increase of 7Kg than that of fresh yield of root with 430.4Kg/10a at the area sown on the seedbed in July 10 and conducted the growing seedling in the same date. The dry yield of roots at the area on the seedbed in June 30 and conducted the growing seedling in 30 days is 351.9Kg110a which was sown on the seedbed in June 20 and carried out the growing seedling in 30 days, and it also shows more increase of 16.4Kg than that of dry yield of root with 335.4Kg110a at the area sown on the seedbed in July 10 and conducted the growing seedling in the same date. Therefore, the seedling period of proper seedbed for high yield bumper crop of Alisma plantago for exporting to Japan is June 30 and the number of days for seedling is 30 days.

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A COMPARATIVE STUDY ON THE PERFORMANCES OF F1 CROSSBRED COWS UNDER RURAL CONDITIONS

  • Nahar, T.N.;Islam, M.;Hasnath, M.A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권3호
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    • pp.435-438
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    • 1992
  • Data were collected on productive and reproductive performance of different $F_1$ crossbred cows (Deshi cows joined by A.I. to Sindhi, Sahiwal, Jersey or Holstein-Friesian Bull semen) reared by farmers in and around the Bangladesh Agricultural University campus at Mymensingh. The traits considered were birth weight, age at first heat, age at first calving, gestation length, post-partum heat period, milk yield, lactation length, dry period and calving interval. Data were analyzed statistically using a completely randomized design and Duncan's Multiple Range Test to compare and determine the significance of between individual group means. It was observed that the Holstein $\times$ Deshi had the highest birth weight (21.4 kg) followed by Sahiwal (17.6 kg), Jersey (16.7 kg) and Sindhi (16.1 kg). Shortest age at first heat (854 and 920 days) and age at first calving (1002 and 1201 days) were found for the Jersey $\times$ Deshi and Holstein $\times$ Deshi crosses respectively. The post-partum heat period were significantly different between breeds with Jersey and Holstein sired calves having the shortest intervals. There was no difference in the gestation length of the four crosses. Holstein $\times$ Deshi and Jersey $\times$ Deshi cows gave the highest milk yields due to longer lactation periods and higher daily milk production. Similarly, Holstein $\times$ Deshi and Jersey $\times$ Deshi crosses had significantly shorter dry periods and Jersey $\times$ Deshi had a shorter calving interval. From this study it may be concluded that exotic genotypes such as Holstein-Friesian and Jersey can perform very well under rural conditions in Bangladesh.