• 현장농수산연구지
• /
• 제8권1호
• /
• pp.43-51
• /
• 2006

본 실험은 젖소의 사료 내 아미노산 중 His, Met, Lys의 부족이 하루 착유횟수를 2회에서 3회로 증가시킨 젖소의 유생산 반응에 어떠한 영향을 미치는 가를 조사하기 위하여 수행하였다. 젖소의 사료 내 His, Met, Lys의 부족을 위해서 조사료로서 그라스 사일리지를 이용하고 또한 농후사료에 이용되는 단백질원으로서 우모분만을 이용하였다. 비록 젖소의 대사에너지 섭취량이 유생산을 위한 요구량보다 훨씬 높았지만 사료 내 특정 아미노산의 부족은 하루 착유횟수를 2회에서 3회 증가시킨 젖소의 유량을 유의적으로 증가시키지 못하였다. 또한 한쪽 유구에만 3회 착유를 적용한 결과 2회 착유된 유구의 유단백질 및 유당의 분비를 감소시키는 것이 조사되었다. 결론적으로 본 실험의 결과는 특정 아미노산이 제한된 사료조건에서 젖소의 하루 착유횟수를 2회에서 3회로 증가시키는 것은 유생산 반응을 변화시킬 수 있을 정도의 유량 촉진방법이 아님을 제시하였다.

• 한국산학기술학회논문지
• /
• 제19권6호
• /
• pp.652-657
• /
• 2018

젖소농가에서 착유생산성에 영향을 미치는 번식관리는 매우 중요한 요소이다. 젖소에서 번식관리는 발정의 조기 발견이 중요하며, 보다 정확하고 신속한 젖소의 발정시기에 대한 신뢰할 수 있는 자동 모니터링이 농가에는 필요한 실정이다. 본 연구에서는 젖소의 발정유무, 활동량변화, 반추위 운동량, 반추위 온도 및 pH 등을 측정하는 기기를 활용하여 발정에 대한 정확도를 측정하였다. 연구에 사용된 생체정보기기 S1(Smaxtec, Austria)는 반추위 내 삽입형타입으로 반추위의 온도, pH, 젖소의 활동량 및 음수횟수 추정 등을 이용하여 발정 유무의 알림을 제공하고, S2(Healthy Cow 24, SCR. Allflex. Israel)는 목걸이 타입으로 반추위 운동량, 젖소의 활동량으로 발정의 유무를 알려준다. 기기에서 수집되는 데이터는 1일 2시간 간격으로 획득하였고, 각각의 기준일(Reference day: RD ; -7~-3, +7~+3)은 수정일(-2, -1, 0, +1, +2)이 5일과 수정 전 7일에서 수정 후 7일에 대한 평균값을 기준으로 비교하였다. 본 논문에서 사용된 S1 기기의 활동성은 기준일(RD : $10.2{\pm}1.0/day$)에 비해 수정일(-1 : $12.5{\pm}1.03/day$ ;0 : $12.9{\pm}1.73/day$)에서 증가 하는 것으로 나타났다. S2 기기의 활동성 또한 기준일 (RD : $40.3{\pm}2.68$)에 비해 수정일(0 : $63.0{\pm}3.66$)에서 증가 하는 것으로 분석되었다. S1의 일일 음수횟수는 기준일(RD : $5.9{\pm}0.89/day$)에서 수정일 전까지는 (-2 : $5.6{\pm}0.98$ ; -1 : $5.7{\pm}0.96$)으로 감소하는 것으로 나타났으나, 수정일(0 : $6.3{\pm}0.86$ ;+2 : $6.0{\pm}0.73$)에는 기준일과 같은 횟수를 보였다. S2의 일일 반추횟수는 기준일(RD : $493.8{\pm}10.92$) 보다 수정일(-1 : $390.2{\pm}13.36$; 0 : $354.1{\pm}16.71$)에 감소하는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제31권5호
• /
• pp.677-685
• /
• 2018

Objective: The objective of the present study was to determine ammonium chloride tolerance of lactating dairy cows, by examining effects of negative dietary cation anion difference (DCAD) induced by ruminal ammonium chloride infusion on performance, serum and urine minerals, serum metabolites and enzymes of lactating dairy cows. Methods: Four primiparous lactating Chinese Holstein cows fitted with ruminal cannulas were infused with increasing amounts (0, 150, 300, or 450 g/d) of ammonium chloride in a crossover design. The DCAD of the base diet was 279 mEq/kg dry matter (DM) using the DCAD formula (Na + K - Cl - S)/kg of DM. Ammonium chloride infusion added the equivalent of 0, 128, 330, and 536 mEq/kg DM of Cl in treatments. According to the different dry matter intakes (DMI), the resulting actual DCAD of the four treatments was 279, 151, -51, and -257 mEq/kg DM, respectively. Results: DMI decreased linearly as DCAD decreased. Yields of milk, 4% fat-corrected milk, energy-corrected milk, milk fat, and milk protein decreased linearly as DCAD decreased. Concentrations of milk protein and milk urea nitrogen increased linearly with decreasing DCAD. Concentration of Cl- in serum increased linearly and concentration of PO43- in serum increased quadratically as DCAD decreased. Urine pH decreased linearly and calculated urine volume increased linearly with decreasing DCAD. Linear increases in daily urinary excretion of $Cl^-$, $Ca^{2+}$, $PO_4{^{3-}}$, urea N, and ammonium were observed as DCAD decreased. Activities of alanine aminotransferase, aspartate aminotransferase, and ${\gamma}-glutamyl$ transferase in serum and urea N concentration in serum increased linearly as DCAD decreased. Conclusion: In conclusion, negative DCAD induced by ruminal ammonium chloride infusion resulted in a metabolic acidosis, had a negative influence on performance, and increased serum enzymes indicating potential liver and kidney damage in lactating dairy cows. Daily ammonium chloride intake by lactating dairy cows should not exceed 300 g, and 150 g/d per cow may be better.

• Asian-Australasian Journal of Animal Sciences
• /
• 제13권5호
• /
• pp.605-612
• /
• 2000

Four young swamp buffalo cows of similar age ranging in weight between 280 to 380 kg and trained to do physical work were used in a study to determine energy and protein requirements for draught using a $4{\times}4$ Latin square designed experiment. The experiment consisted of field trials employing 4 levels of work load, e.g. no work as control, and loads amounting 450 to 500 Newton (N) pulled continuously for 1, 2 and 3 h daily for 14 consecutive days. Cows were fed king grass (Penisetum purpuroides) ad libitum and were subjected to materials balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus retained energy (RE). The results show that EE while not working ($EE_{resting}$) was $0.42kgW^{0.75}MJ/d$ and maintenance ME ($ME_m$) was $0.37kgW^{0.75}MJ/d$. ME requirement increased to 1.65 times maintenance for the work of 3 hours. The energy expended for doing exercise ($E_{exercise}$) was 9.56, 20.0 and 25.86 MJ/cow for treatments 1, 2 and 3 II, respectively. Fat retention was absent in all groups of working cows, but protein retention was only negative for cows undertaking 3 h work. The relationship between $E_{exercise}$ (MJ), work load (F, kN), work duration (t, h) and body mass (W, kg) was found to be: $E_{exercise}=(0.003F^{1.43}t^{0.93})/W^{0.09}MJ$. The maintenance requirement for digestible protein was $2.51kgW^{0.75}g/d$, whereas digestible protein for growth ($DP_{growth}$) and for work ($DP_{work}$) followed the equations: $DP_{growth}=[(258+1.25W^{0.75}){\Delta}Wkg/d]g$ and $DP_{work}=[12.59e^{0.95t}]g$, respectively The coefficients a, b and c for the calculation of $E_{exercise}$ components according to the Lawrence equation were found to be 2.56 J/kgW.m, 5.2 J/kg load carried.m and 0.29, respectively, thus efficiencies to convert ME into work were 0, 16.09, 27.3 and 32.44% for control, 1, 2 and 3 h/d work, respectively. ME and DP requirements for a 250 to 400 kg working buffalo cow allowing to growth up to 0.5 kg/d are presented.

• 농업과학연구
• /
• 제38권4호
• /
• pp.667-672
• /
• 2011

This study was carried out to increase the breeding rate using sustained recombinant bovine somatotropin (bST) and examine the reproductive disorder and disease prevalencies of cow and calf, respectively. Sixty cows were allotted randomly to three groups in randomized complete block design; (1) No treatment, (2) 500 mg bST two times + 250 mg bST SC injection five times from 3 weeks before to 9 weeks after parturition every two weeks, (3) 500 mg bST two times before 3 weeks parturition + 250 mg bST SC injection three times from five to 9 weeks after parturition every two weeks. Developmental data of birth weight, weaning weight, total gain and average daily gain in control was $22.9{\mu}0.45$ kg, $88.0{\mu}1.13$ kg, $65.1{\mu}0.74$ kg and $0.54{\mu}0.08$ kg, respectively. There is no significant difference between Group 1 and 3 in the examined factors. However, there is significant difference between Group 1 and 2 in the birth weight ($24.4{\mu}0.88$ kg), weaning weight ($101.0{\mu}1.77$ kg), total gain ($76.7{\mu}0.9$ kg) and average daily gain ($76.7{\mu}0.9$ kg). Total gain was showed higher in Group 2 and 3 than Group 1 in the >2nd parity, and in Group 2 than Group 1 and 3 in the 1st parity. There is no significant difference in the BCS, no return days and disease occurrence of cow and calf by bST treatment. Number of service per conception was slightly increased in the Group 3 compared to Group 1 and 2. To increase the breeding ability of Hanwoo, it is recommended that 500 mg bST two times + 250 mg bST injection five times from 3 weeks before to 9 weeks after parturition every two weeks.

• Animal Bioscience
• /
• 제34권4호
• /
• pp.567-574
• /
• 2021

Objective: In this study we investigated the effect of seasonal thermal stress on milk production and milk compositions between Holstein and Jersey dairy cows under the temperate-climate in Korea. Methods: A total of 9 Holstein lactating dairy cows (2.0±0.11 parity) which had a daily milk yield of 29.77±0.45 kg, and days in milk of 111.2±10.29 were selected similarly at the beginning of the experiments in each season. Also, a total of 9 Jersey lactating dairy cows (1.7±0.12 parity) which had a daily milk yield of 20.01±0.43 kg, and days in milk of 114.0±9.74 were selected similarly at the beginning of the experiments. Results: Results showed that the average ambient temperature (℃) and temperature-humidity index (THI) were higher in summer, and were lower in winter (p<0.05). The average relative humidity (RH, %) was higher in autumn than that of other seasons (p<0.05). Milk production was significantly decreased (Holstein 29.02 kg/d and Jersey 19.75 kg/d) in autumn than in other seasons (Holstein 30.14 kg/d and Jersey 20.96 kg/d). However, the milk production was negatively correlated in Holstein cows, and positively correlated in Jersey cows with THI values increased from 16 to 80. In addition, milk yield was increased by 15% in Holstein cows and decreased by 11% in Jersey cows with the THI values increased from 16 to 20. The fat and protein content percentage was significantly higher in Jersey milk than in Holstein milk, furthermore the fat and protein content yield was higher in Jersey cow milk than that of Holstein cow's milk with all THIs. Conclusion: From the study results, we concluded that Jersey cows might be less adaptable to low temperature of the winter, and this would have a negative impact on dairy farmer income since Korea's milk price estimation system places a higher value on milk yield than on milk compositions or sanitary grades.

• 대한수의학회지
• /
• 제34권4호
• /
• pp.881-890
• /
• 1994

Skim milk progesterone($P_4$) profiles in 74 dairy cows were determind to monitor postpartum ovarian activity by radioimmunoassay. Milk samples were collected from each cow every 5 days from 10 to 90 days postpartum. Signs of estrus were observed twice daily, and status of the ovaries and uterus were examined every 10 days by rectal palpation. Results are summarized as follows: 1. Cows were categorized into five types by the change of skim milk $P_4$ profiles; Type I(normal) : Cyclic changes of skim milk $P_4$ profiles appeared within 20 days postpartum(12 cows, 16.2%), Type II(cycle delayed) : Cyclic changes of skim milk $P_4$ profiles appeared from 21 to 60 days postpartum(39 cows, 52.7%), Type III(cycle ceased with low $P_4$) : Onset of the estrous cycle within 20 days postpartum but ceased later with low levels of $P_4$ (7cows, 9.5%), Type IV(cycle ceased with high $P_4$) : Onset of the estrous cycle within 20 days postpartum but ceased later with high levels(>3.0 ng/ml) of skim milk $P_4$ (4 cows, 5.4%), Type V(acyclicity) : Skim milk $P_4$ concentration remained low(<1.0 ng/ml) until 80 days postpartum(12 cows, 16.2%). 2. Out of the 17 cows classified as the Type III and Type V by skim milk $P_4$ profiles, 13 cows had inactive ovaries and remaining 6 cows had single or multiple follicular cysts in their ovaries by rectal palpation. All 4 cows of Type IV had a persistent corpus luteum in their ovaries. 3. Approximately eighty percent of the cows had begun ovarian activity by 60 days postpartum and 90.6% by 90 days by skim milk $P_4$ profiles, but only 39.2% by 60 days and 71.7% by 90 days had shown visible estrus signs. The mean days from parturition to the first, second and third ovulations determined by skim milk $P_4$ profiles was $28.0{\pm}11.0$, $46.4{\pm}13.3$ and $66.4{\pm}11.5$ days and the visible estrus signs were 9.3%, 38.1%, and 48.6%, respectively. The mean days from parturition to the first visible estrus was $57.2{\pm}15.9$ days. These results indicated that milk $P_4$ profile of each Types by radioimmunoassay can be utilized for monitoring postpartum ovarian and would be useful for the early detection of ovarian dysfunction in dairy cow.

• Journal of Animal Science and Technology
• /
• 제63권6호
• /
• pp.1265-1274
• /
• 2021

Two field experiments were conducted to improve the conception rate of Hanwoo cow. The first experiment aimed to investigate the physiological condition of Hanwoo cows on estrus, including metabolic profiles and body condition score (BCS). The second experiment investigated the effect of a novel estrus detector on the artificial insemination (AI) conception rate for Hanwoo cows. For the first experiment, 80 Hanwoo cows (2.5 ± 0.10 of parity), approximately one month before estrus, were housed in 16 pens and offered the experimental diets twice daily with free water access. The BCS were recorded, and blood was collected from the jugular veins just before AI. The collected blood was used to measure physiological conditions, such as metabolite and hormone levels. For the second experiment, each cow was equipped with a neck-mounted estrus detector collar, which had a sensor connected through the internet. Approximately one month before estrus, three hundred sixty Hanwoo cows (2.4 ± 0.21 of parity) were assigned into groups with or without W-Tag collar treatments. The animals were managed the same as in the first experiment. The pregnancy rate reached 55% in the first experiment. The concentration of luteinizing hormone (LH) was higher (p < 0.012; 1.56 vs. 1.08 ng/mL) in cows that were not pregnant (NPG) than in cows that were pregnant (PG) after AI. The BCS and other concentrations of metabolites and hormones in the blood were not different in both NPG and PG cows. The ranges of estrogen, LH, and follicle-stimulating hormone for PG cows were 11.9 to 39.0 pg/mL, < 0.25 to 1.98 ng/mL, and < 0.50 to 0.82 ng/mL, respectively. In the second experiment, cows with the estrus detector had lower days open (p < 0.001; 78.1 vs. 84.8 d), insemination frequency (p < 0.001; 1.26 vs. 2.52), and return of estrus (p < 0.001; 70.9 vs. 79.1 d) than those in cows without the estrus detector. In conclusion, the present study indicated that lower LH concentration just before AI potentially increased the pregnancy rate of Hanwoo cows. Furthermore, the application of estrus detectors to Hanwoo cows could improve the conception success rate for AI.

• 한국초지조사료학회지
• /
• 제14권2호
• /
• pp.99-109
• /
• 1994

방목체계하에서 일당 채식허용량(kg OM/cow)의 수준에 따른 일당 채식량 및 산유량의 경향을 방목에 따른 초생의 구성 및 구조적 변화와 관련하여 검토하는데 목적을 두었다. 본 보에서는 5일간 24시간 대상 방목체계하에서 고능력 착유우에 대한 3 수준의 일당 채식허용량에서 방목후 초생의 구조와 관련된 요인들의 변화를 조사한 결과를 요약하였다. 시험시기별 방목적 초생량 및 초장은 시험시기 1에서 5,047kg OM/ha와 341mm에서 초생의 생육이 진행됨에 따라 유의적으로 증가하여 시험시기 3에서 6,877kg OM/ha와 446mmduTdmsk, 채식허용량의 수준을 달리한 시험구 간에는 유의적인 차이가 없없다(평균 6,068kg OM/ha와 410mm). 방목후 초생의 구성은 채식허용량의 수준에 의해 많은 영향을 받았는데, 방목후 초생내 청엽의 수직적 분포높이, 비율 및 밀도는 고사엽과 엽초보다 훨씬 높은 감소비율을 보였고, 방목전 청엽은 지상 50cm까지 분포되어다가 방목후 고 및 중 수준이 채식허용량에서는 25cm까지, 저 수준의 채식허용량에서는 20cm까지 분포되어 있던 청엽은 모두 채식되었다. 방목깊이와 예취된 채식초의 부피는 채식허용량의 수준에 따라 유의적인 영향을 받았다. 방목후 초생량은 방목전 수준에 비해 고, 중 및 저 수준의 채식허용량에서 방목전 수준에 비래 각각 35, 36 및 52%가 감소되었다. 채식허용량과 방목후 초장(r=0.79), 생엽의 비율(r=0.94) 및 생엽의 밀도(r=0.91)간에 각각 고도의 정의 상관관계가 인정되었다.

• 한국초지조사료학회지
• /
• 제16권3호
• /
• pp.183-189
• /
• 1996

The productivity and utilization of four different grasdlegume pastures for grazing management were examined. The pasture mixtures used in this study were orchardgrass + ladino clover (Tl), orchardgrass + alfalfa (T2), perennial ryegrass + alfalfa (T3), and orchardgrass (T4, without legumes) respectively. The pastures were mtationally grazed 7 times with growing cow which had an initial weight of ca 243kg. The gmwth of pasture plants, dry matter (DM) yield, DM distribution, daily DM production, and pasture utilization were investigated at the NLRI, in Suwon, from April to October in 1991 and 1992. The average plant height at each grazing was 32-33m. The average DM content was 17.8%, wil the lowest in TI (16.4%) and highest in T3 and T4 (18.4%). The annual DM production were 9,609 kg (T3), 9,420 kg (Tl), 9,402 kg (T2), and 9,194 kgha (T4) in that order, but no significant differences were found in forage yield between treatments. Most of forage DM was produced in spring season, particularly in May. The daily DM production was highest in May (81.9kg), and lowest in August (33.0kg/ha). The average efficiency of pasture utilization was about 79%, with the lowest in TI (77%), and highest level of utilization was observed in T4 (82%). In this experiment, production and utilization of each pastures were observed similarly. However, the forage nutritive value, botanical composition, and animal performance as affected by different pasture mixtures for suitable grazing management are needed to ascertain.