Oxygen consumption has been regarded as a useful indicator for assessment of mammalian embryo quality. However, there was no standard criterion to measure the oxygen consumption of embryos. Here, we measured oxygen consumption of bovine embryos at various developmental stages was measured using a scanning electrochemical microscopy (SECM). We found that the oxygen consumption significantly increased in blastocyst-stage embryos compared to other stage embryos (from 2-cell-stage to morula-stage), indicating that oxygen consumption reflects the cell number ( versus , p<0.05). In the morula-stage embryos, the oxygen consumption of in vivo derived embryos was significantly higher than that of in vitro produced embryos ( versus , p<0.05). However, there was no significant difference in consumption of oxygen by in vivo and in vitro-derived bovine blastocyst-stage embryos (p>0.05). In the frozen-thawed blastocyst-stage embryos, live embryos showed significantly higher oxygen consumption than dead embryos ( versus , p<0.05). These results indicate that the measuring oxygen consumption by SECM can be used to evaluate bovine embryo quality.

Through the analysis of several blood paramiters (indexes) that were closely related to feed (daily ration) conversion of beef cattle, the results showed that the content of INS(Insulin), TAA(Total amino acid), LAA(Limiting amino acid)and GH(Growth hormone) in the blood would reach the maximum when if the addition of Allium sativum ranged from 66g/headㆍday to 84g/headㆍday and Akkuyn sadtium ranged from 0.3g/headㆍday to 0.4g/headㆍday.

We investigated the differences in survival rates and height growth among 10 sprouting tree species under cattle grazing conditions in a clearcut area of a secondary forest, as well as the relationship between survival and growth and the species' leaf tannin contents. A clearcut area of a deciduous broad-leaved secondary forest was grazed by two breeding cattle from 1990 until 2001. The height and viability of marked sprouting trees in the area were monitored annually before the initial spring grazing period for 12 years. The tannin contents in leaves were measured from 1996 until 1998. The target tree species differed greatly in the patterns of survival and height growth and were classified into four categories based on these patterns. Similarly, tannin contents in leaves varied widely (1.3% to 11.6%) among the species. Survival rates of the target species in 2001 correlated significantly with the tannin contents in leaves. Our findings indicate that tannin content in leaves is an influential factor affecting the survival and growth of sprouting trees under cattle grazing conditions.

Short-term ingestive behavior of cattle was measured for two tropical grasses with contrasting growth forms, centipedegrass (CG; strongly prostrated) and bahiagrass (BG; more erect). Bite dimensions, bite weight and intake rate of animals increased as herbage mass increased in both grasses, showing a steeper initial increase and an earlier and lower plateau in CG than in BG. The results show that strongly prostrated grasses should be grazed when herbage mass is close to the point where the intake response plateaus, in order to maximize both quantity and quality of intake.

This study was carried out to investigate the effects of cattle slurry application in paddy land cultivated with whole crop rice on the properties of soil and water. A field study was conducted at Baeksan-myeon, Kimje, Jeonbuk province in Korea on clay loam soil for 3 years. All plots were arranged in completely randomized design with three replicates. The contents of organic and inorganic properties in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (P＜0.05). The concentrations of NO₃-N, NH₃-N and PO₄-P in discharge and leaching water were different significantly between both treatments.

This study was carried out to investigate the effects of cattle slurry application on the productivity and nutritive values of whole crop rice in paddy land. A field study was conducted at Baeksan-myeon, Kimje, Jeonbuk province in Korea on clay loam soil for 3 years. All plots were arranged in completely randomized design with three replicates. The yield of dry matter (DM) of whole crop rice in treatment of cattle slurry significantly decreased as compared with that of treatment of standard fertilizer (P＜0.05). However, nutritive values of whole crop rice were not different significantly between both treatments.

The experimental work was conducted to investigate the effects of the application level of composted cattle manure (CCM) on forage productivity using whole crop barely (WCB)-whole crop rice (WCR) double cropping system for 3 years. Main plot was consisted of application level of CCM such as 150%, 200% and control plot. The total DMY of forages under WCB and WCR in treatment of CF significantly decreased as compared with that of treatment of CCM 150%. However, NDF, ADF and CP content of WCB and WCR were hardly influenced by CCM application.

The experimental work was conducted to investigate the effects of the application level of composted cattle manure (CCM) on forage productivity using Italian ryegrass-WCR double cropping system for 3 years (2006~2008). Main plot was consisted of application level of CCM such as 150%, 200% and control plot. The total day matter yield (DMY) of Italian ryegrass and WCR in treatment of CCM 150% and CCM 200% significantly decreased as compared with that of treatment of chemical fertilizer (CF). However, NDF, AND and CP content of Italian rye grass and WCR were hardly influenced by CCM application.

The experimental work was conducted to investigate the effects of the application level of composted cattle manure (CCM) on forage productivity using rye-whole crop rice (WCR) double cropping system for 3 years. Main plot was consisted of application level of CCM such as 150%, 200% and control plot. The total DMY of of rye-WCR in treatment of CCM 150% significantly decreased as compared with that of treatment of CF and CCM 200%. However, NDF, ADF and CP content of rye and WCR were hardly influenced by CCM application.

Our previous study conducted in a wasted mulberry plantation showed significant decline of leaf productivity of mulberry (Morns sp.) by cattle grazing in three years (Ogura et al., 2009). This means t㏊t improvement of understory vegetation is essential to use such wasted areas as grazing lands. In this study, the mixture of seeds (Dactylis glomerata, Lolium perenne, Poa pratensis and Trifolium repens, 15:15:5:2) was seeded on 18 Sep. 2007, in nine experimental plots (6 m × 6 m each) with different seeding rates (L: 37 ㎏/㏊, M: 56㎏/㏊ and H: 74㎏/㏊, three replications) in the wasted mulberry plantation described in the previous paper (paddock A) (Ogura et al., 2009). Two cows were grazed in the paddock for 42 and 54 days in 2007 and 2008, respectively. No fertilizer nor herbicides were applied in the paddock. The coverage of the sown species and weeds, and the proportion of bare area were recorded on 19 Sep. 2007, 16 Nov. 2007, 21 May 2008 and 21 May 2009. T. repens rapidly covered the understory; the coverage ranged 49.4-71.7% in 2008-2009 (Fig. 1). D. glomerata and L. perenne also increased to 10.6-18.3% and 20.6-33.9% in 2009, respectively, regardless to the seeding rates. In contrast, the proportion of bare area rapidly decreased. The quick establishment of the sown plants probably due t㏊t defoliation and trampling of cows suppressed the growth of native plants. In conclusion, the seeding rate of 3.7 ㎏/㏊ is sufficient to establish herbage plants in wasted mulberry plantations under cattle grazing.

Mulberry (Morus sp.) plantations have been deteriorating in Japan due to decline of silk industry. In mountainous areas, large part of the mulberry plantations has been wasted. Cattle grazing in the wasted mulberry plantations is a practical system to reuse the wasted areas for food production, because mulberry leaves are highly nutritive (Ezenwa and Kitahara, 2001), productive (Kitahara et al., 2002) and palatable to cattle (Ogura et al., 2008). In this study, the productivity and quality of mulberry leaves were investigated for 3 years in a wasted mulberry plantation grazed with beef cows, in Minamisanriku town, Miyagi, Japan. Cattle grazing started in September 2005 (paddock A, 44 a) and June 2006 (paddock B, 96 a). For each paddock, two pregnant cows were grazed from June to August-October in 2006-2008. In the paddocks A and B, four mulberry trees were chosen and the leaf mass and chemical composition were measured in mid-June and late August (pre-grazing leaf mass) during 2006-2008. A non-grazed paddock was also measured in 2007-2008. Leaf productivity of mulberry trees significantly decreased with cattle grazing; pre-grazing leaf mass changed from 246.8 g to 10.4 g DM/tree and 286.2 g to 17.6 g DM/tree in the paddock A and B, respectively (Fig 1). In contrast, 149.2-365.1 g DM/tree of leaves was produced in the non-grazed paddock. Chemical composition was stable during the three years in all paddocks. It is concluded that cattle grazing gives severe damage to leaf production of mulberry trees in three years.

Successful in vitro embryo production heavily relies on the normal maturation and fertilisation of oocytes. We examined the normal and abnormal fertilisation of zebu cattle oocytes matured in vitro. Immature cumulus oocyte complexes (COCs) from zebu cattle ovaries at slaughter were matured in vitro (IVM) for 24 h. The oocytes were either fixed, stained and examined for nuclear changes or fertilised in vitro (IVF) with Percoll-separated, heparintreated spermatozoa (1.0 /mL) of zebu (n = 7) and crossbred bulls (n = 7). After 18 h of sperm-COCs co-incubation at C with 5% in humidified air, the presumptive zygotes were fixed, stained and examined for pronuclei. The number of oocytes retrieved per ovary was 5.4 0.7. The percentage of matured oocytes was 73.0. The difference in motility of spermatozoa before and after Percoll seperation was significant (p<0.001). The percentages of normal and abnormal fertilisation (polyspermia and oocytes with one pronucleus) varied significantly depending on individual bulls (p<0.05). A protocol for IVF of IVM oocytes in Bangladeshi zebu cattle is developed. A future study may elucidate the capacity of such IVM-IVF oocytes to develop to the blastocyst stage for transfer to surrogate mother.

This study was performed to investigate the possibility of repeated superovulation treatment at interval from 27 days to 41 days in Hanwoo cattle and to compare with superovulation effect between doses of FSH 200 mg and FSH 400 mg. Different doses of FSH (200 mg or 400 mg) were injected at Day 8 after controlled internal drug release (CIDR) treatment for superovulation of Hanwoo donors following CIDR treatment (Day 8 after the estrus). Superovulation was repeated four times for one donor and number of corpus luteum (CL), number of embryos, number of transferable embryos and pregnancy rate after embryo transfer (ET) were investigated. 5 cows were used for each FSH treatment (10 cows in total). Average number of CL were and for the donors treated with FSH 200mg and FSH 400mg, respectively. Average number of embryos collected were and for the donors treated with FSH 200 mg and FSH 400 mg, respectively. Average number of transferable embryos were and for the donors treated with FSH 200 mg and FSH 400 mg, respectively. The pregnancy rate following ET with embryos collected from 200 mg FSH treated donors and 400 mg FSH treated donors were 61.9% and 53.8% respectively. The numbers of embryos tended to be decreased as the numbers of repeat of superovulation were elapsed. These results indicated that superovulation treatment by about a month to Hanwoo donors is usable and 200 mg of FSH is preferable for simple FSH treatment following CIDR treatment.

본 시험은 2003년부터 2005년까지 방목 혼파 초지에 우분퇴비 시용에 따른 사초의 무기성분 함량변화를 구명하기 위하여 난지농업연구소 조사료포장에서 수행되었다. T1) 화학비료 100 %, T2) 화학비료 50%+퇴비 50%, T3) 화학비료 25%+퇴비 75%, T4) 퇴비 100%, T5) 퇴비100% (1년차) +화학비료 100% (2년차) +퇴비 100%(3년차), 76) 퇴비 100%(1년차)+화학비료 100%(2년차)+화학비료 100%(3년

We separately cultured follicular oocytes collected from individual ovaries of slaughtered Korean native cows and examined both the embryonic development rate and pregnancy rate after embryo transplantation according to the meat yield and quality grades of the source beef carcass. Oocytes from meat yield grade B cows exhibited a higher fertilization rate and embryonic developmental rate to the eight-cell stage than oocytes from grade A or C animals (p<0.05), but there was no significant difference in rate of development to the blastocyst stage among meat yield grades A, Band C. The oocyte cleavage rate and development rate to the eight-cell stage from meat quality grade 3 cattle was higher than grades 1++, 1+, 1 and 2 (p<0.05). Embryos derived from grade animals displayed a development rate to the blastocyst stage of 19.4%, which was also higher than all other meat quality grades (p<0.05). Transplantation of in vitro-cultured oocytes from meat yield grade A ovaries led to a higher pregnancy rate (64.2%) than in vitro-cultured oocytes from meat yield grade B ovaries (56.5%), but there was no significant difference between the two groups in pregnancy or abortion rates. In conclusion, embryonic development rate and pregnancy rate has a close relation to meat quality grades of the source beef carcass, this results is to give information for the Korean native cows improvement of breed.

The aim of the present recent study was to compare the protein patterns in the vaginal mucus of Hanwoo cattles during spontaneous and CIDR induced-estrus. Ten cattles, who had been observed in estrus, received no treatment and served as the group of cattles with normal spontaneous estrus. Thirteen cattles in the CIDR received an CIDR insert on day 14 were removed and cattles were injected GnRH on day 15. Vaginal mucus samples were collected from all cattles at the same time the single AI in cattles with spontaneous estrus and the AI in cattles with induced estrus. Spontaneous and CIDR-induced estrus vaginal mucus samples were analyzed on two different array surfaces: cation-exchange (CM10), anion-exchange (Q10). In addition, using the NaCl solution by which the proteins combined after washing are 0.5, 1 and 2 M, it was fractionated and a protein was collected successively. The results are summarized as follows: 1) Ionic surfaces chemistries (Q10 and CM10) gave the best results in terms of detectable protein peaks, with more than 100 protein peaks in the two fractions and under each condition. 2) Protein mass spectrometer using 11 different proteins in protein identification of 7 were able to determine the protein. List of identified proteins as follows; Ribosome-binding protein 1, GRIP 1-associated protein 1, Katanin p60 ATPase-containing subunit A-like 1, Protein FAM44A, DUF729 domain-containing protein 1, Prolactin precursor, Dihydrofolate erductase. Conclusively, on the basis of this study, protein expression in the vaginal mucus could be used as an indicator for time of estrus manifestation in order to increase conception rates by applying AI at an optional time.

본 실험에서는 답리작으로 호밀과 헤어리 베치를 단파 혹은 혼파 재배 시 화학비료와 가축분뇨의 시용에 따른 생산성과 사료가치를 평가하여 양질의 조사료 자원을 확보하고자 실시되었는데, 그 결과를 요약하면 다음과 같다. 답리작으로 호밀 단파구와 호밀 및 헤어리 베치 혼파구의 연 평균 건물과 가소화양분총량(TDN) 수량은 각각 ha 당 7.2와 4.0 ton 및 8.0과 4.4 ton으로 헤어리 베치 단파구의 연 건물수량과 TDN 수량(4.5 및 2.7 ton