The main objective of this experiment was to investigate effects of two different feeding systems on body weight, milk yield, milk composition, and mineral and fatty acids content of Holstein dairy cows’ milk. Sixteen of 25 months-old Holstein dairy cows were assigned to two groups (n=8) to study effects of the feeding system for 150 days. Two feeding systems were compared for five months; Group 1 was housed indoors and mainly fed a concentrate diet, Group 2 was maintained outdoors for five-seven hours/day on various kinds grass in a pasture. The experiment was conducted June-October 2017. Results revealed the indoor-fed cows had higher body weight, that was significant compared with the outdoor-based feeding system of Holstein dairy cows (p<0.05). Indoor-raised milking cows had higher milk yield (32.45 kg) as compared with pasture-raised milk yield (26.44 kg). Cows fed indoors significantly increased milk yield, total protein content, lactose, citric acid level, and lowered level of total solid and free fatty acids relative to the pasture-fed milking cows (p>0.05). There were higher levels of mineral content and fatty acid content in the milk of indoor-fed dairy cows than the pasture-raised dairy cows (p>0.05). Our study results demonstrated the potential benefits of the indoor feeding system for increased body weight, milk yield, mineral and fatty acids content summer through autumn when low pasture growth rates and quality may otherwise limit production.

본 연구는 경기지역 도축돈 및 도축우의 폐렴병변에서 Mycoplasma spp.의 발생 분포를 조사하고자 수행하였다. 부천 소재 도축장에 출하된 소와 돼지의 폐에 대하여 육안적 검사를 하고, 이 중 병변을 보인 소 192두와 돼지 257두의 폐에 대한 PCR 검사 결과, Mycoplasma spp.는 소에서 147두(76.5%), 돼지에서는 203두(80.9%) 에서 각각 검출되었다. 소, 돼지 각각의 Mycoplasma spp.에 대한 세부 primer를 이용한 검사 결과에서는 소에서 M. agalactiae가 16두(8.3%)에서 검출되었으나, M. dispar, M. bovis 및 M. bovirhinis는 검출되지 않았다. 돼지에서는 M. hyo-pneumoniae가 74두(28.8%), M. hyorhinis가 13두(5.1%) 검출되었다. M. hyosynoviae는 검출되지 않았다. 본 연구를 통해 경기지역 도축우 및 도축돈에서 Mycoplasma성 폐렴이 상재하고 있음을 확인하였다.

본 연구는 체성숙이 완료된 15개월령 이상의 한우 암소로부터 초음파 측정 장치를 활용하여 조사된 등지방두께(UBF), 배장근단면적(UEMA), 근내지방도(UMS)의 형질들에 대한 유전능력을 추정하기 위한 통계분석방법을 도출하기 위한 연구로써 신체충실지수 및 월령에 대한 사전 보정의 효율성을 알아보고 유전평가를 위한 형질별 유전모수를 추정함으로써 유전능력 추정의 효율성을 향상하기 위한 방안을 도 출하고자 실시하였다. 분석에 이용된 자료는 2001년부터 전국의 1,004농가에서 사육중인 15개월령 이 상의 한우 암소 38,663두로부터 조사된 초음파 측정 육질관련 형질들에 대하여 조사된 자료를 이용하였다. 흉위 및 도축형질들에 대한 성장곡선함수식을 추정하기 위하여 농가-년-월(HYM) 및 신체충실지 수(BCS)에 대한 통계모형식을 통하여 사전보정을 실시하고 Von Bertalanfy함수식을 이용한 비선형 성장곡선 함수식을 추정하였다. 또한 도축형질들에 대하여 개체별로 조사된 관측치는 성장곡선 함수식에 대한 편차로 자료변환한 후에 유전모수를 추정한 결과, 각 형질별 유전력은 UBF에서 0.29, UEMA는 0.56 및 UMS에서 0.49의 추정치를 보였다.

본 연구는 우리나라 일반 농가에서 사육중인 한우 암소 348두의 도체중, 등심단면적, 등지방두께 및 근내지방도에 대하여 EBV(Estimated Breeding Value) 및 GEBV(Genomic Estimated Breeding Value)의 정확도를 비교하였다. EBV 분석은 한우 암소 348두의 혈통정보와 농협경제지주 한우개량사 업소의 당대검정우 및 후대검정우의 혈통정보 및 표현형정보를 이용하여 혈연계수행렬(Numeric Relation Matrix, NRM)을 구축하여 BLUP(Best Linear Unbiased Prediction) 방법으로 분석하였다. GEBV 분석은 표현형정보와 유전체정보가 있는 후대검정우 3,820두를 참조집단으로 이용하여 한우 암소 348두의 SNP 50K 정보와 유전체 혈연 행렬(Genetic Relationship Matrix, GRM)을 구축하여 GBLUP(Genomic Best Linear Unbiased Prediction) 방법으로 분석하였다. 그 결과, 한우 암소 348두 에 대한 EBV 및 GEBV의 정확도 차이는 도체중, 등심단면적, 등지방두께 및 근내지방도에서 GEBV의 정확도가 각각 22.90%, 11.14%, 12.28% 및 8.69% 증가됨을 보였다. 이러한 결과는 유전체 선발 시 육종가 추정의 정확도 증가를 볼 수 있을 것으로 기대되며, 이는 유전체선발을 위한 기초자료로써 활용될 수 있을 것으로 판단된다.

Cryopreservation of oocytes by vitrification technique may contribute a lot in the field of reproductive biotechnology. The objectives of the present study were to evaluate the effectiveness of two cryo-devices for vitrification of immature oocytes of indigenous zebu cows. Slaughter house derived immature cumulus-oocyte-complexes (COCs) of cows were vitrified using 15% dimethyl sulphoxide (DMSO) as cryoprotective agent (CPA) with 0.5 mol sucrose in TCM 199 supplemented with 20% FBS. Vitrification of COCs was completed after immediate plunging of COCs loaded cryotop or French mini straw into the liquid nitrogen (LN2). Then the COCs containing cryotop or French mini straws were warmed in 0.25 mol sucrose and 20% FBS supplemented TCM 199 followed by in vitro culture in 50 μl droplets of bicarbonate buffered TCM 199 supplemented with 10% FBS, pyruvate, FSH and oestradiol for 24 hrs at 39°C with 5% CO2 in humidified air. After maturation culture, oocytes were denuded and examined under inverted microscope for presence of polar body as the indication of maturation. Denuded oocytes were also stained by whole mount technique using 1% orcein to examine the maturation by presence of MII chromosomes. The in vitro maturation rate was significantly (p<0.05) higher in oocytes vitrified and warmed using crytop (47.1±6.9%) than that of French mini straw (15.9±12.5%). Moreover, in vitro maturation rate was significantly (p<0.05) highe r in control oocytes (not vitrified) (84.5±14.2%) than that of vitrified oocytes. In conclusion, cryotop is better than French mini straw as cryo-device for vitrification of bovine immature oocytes

A diverse of recommendation has been made for the structure and management of dairy cows, despite demanding research, the relationship between lactation number and various factors is yet to be established. The present study was aimed to investigate the covariance among lactation number, growth performance, calving interval, and milk production was considered to increase an efficiency of selection schemes and to manage more efficiently Holstein dairy cows that have been raised on small-scale family farms in Republic of Korea. For that purpose, the data were observed from 850 Holstein dairy cows, which a total of 3929 milking, since April 2016 - January 2017. We measured the body weight, height, age, calving interval, and milk production of the each dairy cow. Also, information about the date of lactation, calving interval, and milk production was recorded using an automatic milking system(AMS) with identification numbers. Milk production was calculated per udder quarter in the AMS. Our study results showed the increased average body weight(p>0.05) in 1, 2, 3, and 4th lactating dairy cows and afterwards, we noticed the tendency on the average body weight(p<0.05) per lactation progressed. There was no significant difference noticed on height measurement of dairy cows. From the processing data of 850 Holstein dairy cows, the lactation number 1 and 7 had a greater calving interval with significantly lowered milk production, and the lactation number 2, 3, 4, 5, and 6 had significantly lowered the calving interval(p<0.05) with a greater milk production. From our study results, we evidenced that there is a significant relationship between the lactation number, growth performance, calving interval, and milk yield, and the maximum production of milk occurring in the 3rd and 4th lactation dairy cows. The achieved results from this study can be used by the small-scale farmers to encourage the structure and management of growth performance, calving interval, and milk yield in Holstein dairy cows in Korea.

본 연구는 부모의 혈통정보를 모두 아는 혈통 및 고등등록우로 등록된 한우 암소 25,516두의 선형 및 외모심사형질에 대해 유전모수를 추정하였다. 각 심사형질에 영향을 주는 것으로 판단되는 주요인을 선 정하여 다형질 개체모형에 적용하여 EM-REML 알고리즘 분석방법을 통해 각 형질에 대한 유전력과 유 전상관과 표현형상관을 추정하였다. 한우 암소의 17개 선형심사형질 및 10개 외모심사형질(종합점수 포 함)의 유전력 추정치의 범위는 0.03(유두배열)에서 0.42(체장)까지로 추정되었다. 체고, 체장, 강건성, 체심, 윤곽성, 정강이두께, 피모의 색, 엉덩이기울기, 고장, 좌골폭, 넓적다리의 두께, 유방용적, 유두길 이, 유두배열, 발굽기울기, 뒷다리 비절기울기, 뒤에서 본 뒷다리자세, 체적․균형, 자질․품위, 머리․목, 전구, 중구, 엉덩이, 넓적다리, 유기, 지제보양 및 종합점수의 유전력은 각각 0.4, 0.42, 0.27, 0.25, 0.06, 0.14, 0.22, 0.31, 0.19, 0.17, 0.29, 0.04, 0.07, 0.02, 0.11, 0.03, 0.16, 0.27, 0.08, 0.15, 0.14, 0.14, 0.19, 0.16, 0.05, 0.08 및 0.3으로 추정되었다. 한편, 다형질개체모형에 의해 추정된 17개 선형심사형질과 종합점수에 대한 유전상관추정 결과는 다음과 같다. 고장과 좌골폭간에 0.96의 가장 강 한 양(+)의 유전적 관계를 나타내었다. 반면 발굽기울기와 뒷다리 비절기울기간에는 -0.57의 가장 큰 음(-)의 유전상관을 보였다. 전체외모 형질인 체고, 체장, 간겅성 및 체심은 각 형질간에, 그리고 기타 형 질들과 강한 양(+)의 유전상관관계를 나타내었다. 특히 체고 및 체심과 고장 및 좌골폭간에 높은 양(+)의 상관관계를 나타내었으며, 체고와 엉덩이기울기간에는 0.32의 양(+)의 상관을 나타내었다.

This study was conducted to examine the effect of corn (Zea mays L.) - soybean (Glycine max L.) silage prepared by intercropping method on the nutritive value of the silage, in vitro rumen fermentation characteristics, dry matter degradability, as well as milk yield and milk composition of dairy cows. In a couple of experiments intercropped corn-soybean silage (CSBS) was compared with corn silage (CS) and/or Italian ryegrass hay (IRG). Numerically, CSBS had higher crude protein, ether extract, and lactic acid contents compared to CS. In vitro rumen fermentation analysis demonstrated that up to a 24-h incubation period, both CS and CSBS showed higher total gas production, ammonia N concentration, and dry matter degradability compared to IRG (p<0.05). The investigation on animals was conducted in a commercial dairy farm located in Gyeongju, South Korea, employing 42 Holstein cows that were divided into 2 group treatments: CS and CSBS in a completely randomized design. Although no significant difference was observed in milk yield, animals fed on CSBS showed significantly higher milk protein (p<0.05) and milk fat content (p<0.01), compared to animals fed on CS. Taken together, our findings indicate that corn-soybean silage that is cultivated, harvested, and prepared through intercropping can improve the protein content of the silage, and can also enhance in vitro rumen fermentation, dry matter degradability, and performance of dairy cattle.

This study was designed to investigate the carryover effects of high-forage to concentrate (F: C) diet in bred heifers on feed intake, feed efficiency (FE) and milk production of primiparous lactating Holstein cows. The experiment was conducted for 589 days (d) from onset of pregnancy through to the end of first lactation. Twenty-four bred heifers (Body weight: BW= 345.8 ± 45.4 kg and 15 ± 1.2 mon of age) randomly assigned to two groups of 3 pens containing 4 heifers each and fed high forage (HF) diet with F: C ratio of 91.7: 8.3% and low forage (LF) diet with F: C ratio of 77.8: 22.2% throughout the pregnancy period. After calving, lactating cows were fed total mixed ration (TMR) based diet. No differences (p > 0.05) were observed in dry matter intake (DMI) of bred heifers and primiparous lactating cows in both HF and LF groups. The FE of mid-to-late lactation period was higher (p< 0.05) in HF than LF group. However, the HF group showed higher (p < 0.05) milk yield, 4 % fat corrected milk (FCM) and energy corrected milk (ECM) than LF group during the 305 d lactation. The LF group showed higher (p < 0.05) milk fat, crude protein (CP), milk urea nitrogen (MUN), solid not fat (SNF) and somatic cell count (SCC) than HF group. It is concluded that restriction of F: C ratio to 91.7: 8.3% to bred heifers has the potential carryover effects to maintain higher milk yield and FE with no adverse effect on feed intake and milk composition of primiparous lactating Holstein cows.

This study investigated the synergistic effects of a combination of cephalexin and gentamicin (CCG) against Streptococcus spp. isolated from bovine milk. Minimum inhibitory concentrations (MICs) and fractional inhibitory concentration (FIC) index were determined for 12 bacteria isolated from 12 bovine farms in Gyeongnam province. The MIC ranges of cephalexin, gentamicin and CCG were 0.25-0.5, 0.5-2.0 and 0.06-0.125 μg/mL, respectively. In addition, the FIC index range of CCG against the isolates was 0.32-0.34, showing a synergistic effect in the checkboard assay. In conclusion, CCG has a high antibacterial activity against Streptococcus isolates and may be utilized in the treatment of bovine streptococcal mastitis.

Commercial applications of OPU/IVP were to produce embryos and calves from high genetic cows.The aim of this present study was to compare the number of recovered oocytes and cultured in vitro produced embryos from Ovum Pick-up (OPU). OPU derived embryo production was carried out of oocytes by ultrasonographic guided follicular aspiration and then produced in vitro produced blastocysts by IVP culture system. In result, the rate of recovered oocytes was obtained 612 (57.2%) and 451(73.7) G1+G2 grade oocytes. No difference of recovered rate (51.1~62.1%) was seen in six donor. The rate of cleavage and blastocyst development were obtained 320 (70.9%) and 78 (24.4%) that was 3.3±0.4 cleaved embryo and 0.9±0.2 blastocysts per session. Cleavage rate of OPU oocytes in No. 6 donor was 90.6%, significantly (P<0.05) higher than that in the other donors, However, blastocysts was similar (25.8~30.0%). In conclusion, limited numbers of OPU oocytes had competent development when cultured in SOF culture medium

This study determined diagnostic threshold of polymorphonuclear cells (PMN) for cytological endometritis (CEM) and its impacts on reproductive performance in dairy cows. Uterine cytology using 407 Holstein cows was performed at 4 weeks postpartum and proportion of endometrial cells and PMN was evaluated. A receiver operating characteristics curve was built to assess the cutoff level above which the PMN proportion affected the hazard of pregnancy by 200 days postpartum. The cutoff level for CEM was set at ≥14% PMN (sensitivity = 31.3%, specificity = 81.7%, P < 0.05). Cows with CEM had a lower probability of resumption of cyclicity (OR = 0.58 P < 0.05) and lower hazard of pregnancy by 200 days postpartum (hazard ratio = 0.58, P = 0.0001) than cows without CEM. Cows with CEM tended to have a lower probability of pregnancy to the first insemination (OR = 0.65, P < 0.1) and a greater number of insemination per conception (2.3 vs 2.2, P < 0.1) than cows without CEM. In conclusion, the threshold level of PMN was 14% to define CEM at 4 weeks postpartum and CEM decreased subsequent reproductive performance in dairy cow

This research was conducted to investigate the effects of feeding high and low forage diets with different forage sources on rumen fermentation characteristics and blood parameters of Holstein cows during the dry period. Eight Holstein cows were completely randomized assigned to two groups and repeated measurement was utilized in the analysis. Cows in two treatments were fed with diets with high (F:C = 70:30, 70F; forage source: mixed-sowing whole crop barley and Italian ryegrass silage, BIRG) and low (F:C = 55:45, 55F; forage source: tall fescue hay, TF) forage level. Rumen fluid pH was higher in 70F group. Levels of acetic acid, propionic acid, and butyric acid showed a similar pattern: from the lowest value at 07:30 h to the highest at 10:30 h and then decreased in both groups. The ratio of acetic acid to propionic acid was significantly higher (p < 0.05) in 55F group at 09:30 and 10:30 h. Rumen fluid NH3-N concentrations were significantly higher (p < 0.05) in 70F group at 09:30 and 10:30 h. Blood urea nitrogen was significantly higher (p < 0.05) in 70F group. It was concluded that BIRG based diet with a high forage level had no adverse effects on rumen fermentation, some blood chemical parameters, and immune system in dry Holstein cows and could be used as a forage source instead of imported TF.

This study was carried out to evaluate the influencing factors that affect the reproductive performance of cows at the Monirampur upazila in Jessore district of Bangladesh. A total of 224 cows were brought to the upazila livestock hospital for artificial insemination (AI). The cows were inseminated between 12 to 18 hours from the onset of estrus and data was obtained from the owner. Out of 224 cows, 133 became pregnant and 91 were non pregnant. In this study, the overall pregnancy rate was 59.29%. Among the age variability, the highest pregnancy rate (70.27%) was at the age of 4 years old. In case of breed variation, the highest pregnancy rate was observed in local breed (69.07%) compared with other crossbred cows. Hence the breed variations significantly influence the conception rate of cows. According to the parity, we found that the pregnancy rate was increasing with their parity but decreasing after 4th parity. The highest conception rate was observed in 3rd parity (67.74%) which was significantly higher than that of heifers (Parity-0). Here we also found that the types of bull semen used for AI had no significant effect for pregnancy rate. The skills of AI technician for AI to cows were significantly affecting the pregnancy rate. However, this study is not enough for rating and comment about the reproduction performance of cows. Therefore, further extensive study is needed for rating and recommendation for the cattle up gradation at that particular area.

본 연구는 분만간격과 비유곡선 모수들 간의 상관관계를 규명하기 위하여 농협중앙회 젖소개량사업 소에서 진행하고 있는 유우군 능력검정사업에 참여하고 있는 홀스타인 젖소로부터 조사한 착유기록 36,505개를 분석하였는데, 분석에 이용된 착유기록은 모두 2011년부터 2013년 사이에 분만한 경산우 로부터 조사하였다. 비유곡선 모수는 Wood 모형을 적용하여, SAS 9.2 NLIN Procedure를 이용해 추 정하였다. 분만년도-계절(봄, 여름, 가을, 겨울)효과와 산차(2, 3, 4산차)의 효과를 고정효과로 한 다 형질 일반선형모형으로 SAS(GLM procedure)를 이용하였다. 분만간격, 305일 유량, 비유곡선모수(A, b, c), 비유지속성, Peak 일시 및 Peak기 유량에 대해 분만년도-계절과 산차의 효과는 모두 유의적 으로 나타났다(p<0.05). Wood 모형으로 추정한 비유곡선 함수는 2, 3 및 4산차에 대해 각각 yt = 24.66t0-175e-0.00302t, yt = 24.69t0-192e-0.00334t 및 yt = 24.22t0.200e-0.00341t으로 추정되었다. 분만간격과 305일 유량, 모수값 A, b, c, 비유지속성, Peak 일시 및 Peak기 유량과의 표현형상관(잔차상관)은 각 각 0.093, -0.014, 0.028, -0.046, 0.099, 0.085 및 0.052으로 나타났다. 분만간격이 길어지면 비유 곡선의 상향경사도, 비유지속성, Peak 일시, Peak기 유량은 증가하고, 비유곡선의 하향경사도는 감소 하여, 305일 유량은 증가할 것으로 판단된다.

본 시험은 성 성숙기의 한우 암송아지 18두(14개월령, 평균체중 251kg)를 이용하여 저 수준의 농후사 료 급여에 따른 성장과 번식능력에 미치는 영향을 규명하기 위하여 실시하였다. 공시축은 시판 한우 번 식우용 배합사료를 체중의 0.8%(T1) 및 1.2%(T2)씩 총 30개월(사양시험 20개월, 번식능력시험 10개월) 동안 섭취하였으며, 처리구당 9두를 2우리에 완전임의 배치를 하였다. 본 시험의 사양시험 결과를 한국 가축사양표준의 영양소 요구량과 비교해 볼 때, T1구에서 성장이 제대로 되지 못한 이유는 에너지 보다 는 단백질 섭취부족 때문인 것으로 나타났다. 공시축의 체형변화에서 저 영양수준으로 인하여 영향을 가장 많이 받는 부위는 흉폭과 체장이었으며 특히, 흉폭은 시험시작시보다도 종료시 측정치가 오히려 3.7% 작았다. 난소의 크기는 T1구가 T2구의 약 63%수준밖에 되지 않았으며, 수태율(33.3% : 77.8%)과 송아지의 생시체중(22.5kg : 29.5kg)도 T1구에서 심각하게 저하되었다. 따라서 한우번식우 사양에 있 어서 성성숙기 이후에도 에너지보다는 단백질 공급수준에 의해 사양성적 및 번식능력에 많은 영향을 끼 치는 것으로 나타났다.