본 연구는 제주특별자치도에 유입된 Myocastor coypus Molina, 1782 (Nutria)의 퇴치를 위해 이루어졌다. 서식확인 및 퇴치는 2013년 9월부터 2013년 11월까지 이루어졌고, 그후 퇴치 성공여부를 확인하기 위해 2022년 6월까지 조사가 이루어졌다. 서식 확인 및 포획은 무인카메라, 청문조사, 문헌조사, 먹이유인을 통한 트랩 포획법을 사용하여 진행하였다. 후속조사는 Nutria의 행동반경을 감안하여 조사범위를 비교적 넓게 설정하여 서식지역(퇴치지역)을 중심으로 4.0㎢ 내 습지 및 하천 조사를 진행하였다. 그 결과 서식 확인지역은 제주특별자치도 제주시 구좌읍 송당리 소재의 송당목장에 서만 발견되었으며, 방목장 내 수로와 연못에서 서식흔적(족적, 배설물, 굴)이 확인되었다. 포획개체는 총 8개체였으며, 암컷 4개체, 수컷 3개체였다. 1개체는 서식확인 시 확인되어 부패 정도가 심해 암·수의 구별이 어려웠다. 후속조사는 설정한 조사범위 내 항시 물이 있는 성읍저수지, 천미천, 몰순이못을 중심으로 서식지와 그 주변을 정밀조사하였으나 서식흔적이 확인되지 않았다. 따라서, 제주도에 서식하는 Nutria는 완전히 퇴치된 것으로 판단된다. 제주특별자치도에서 Nutria의 퇴치가 성공적으로 이루어진 것은 Nutria의 서식 확인 후 빠른 포획을 통해 정착단계 초기에 퇴치가 이루진 것과 제주도 지질 특성상 물이 항시 고여있는 습지가 드물어 확장의 시기가 늦어진 것이 시너지 효과를 일으켜 성공적인 퇴치가 이루어진 것으로 판단된다. 이 결과들은 외래종의 유입에 대한 대처는 그 종의 생태특성을 신속하게 파악하고, 올바른 대처를 통해 확장단계 이전 정착 초기 단계에서 관리 및 퇴치를 통해 교란이 일어나기 전 또는 교란 초기에 차단하는 것이 매우 효과적인 방법임을 시사한다.

본 집쥐 퇴치 계획은 대한민국 최대 슴새 번식지 및 흑비둘기 서식처로 천연기념물 제333호로 지정되어있는 제주특별 자치도 소재(33°55′13.04″N, 126°38′19.98″E) 무인도서인 사수도 내 집쥐 퇴치를 위해 이루어졌다. 구제 연구는 2015년 11월부터 2021년 2월까지 총 12차례 진행되었고, 조사는 섬 전역을 천천히 배회하며 출발지점과 도착지점을 동일하게 하여 조사하는 선조사법을 이용하였다. 이 때 확인된 배설물, 터널 등 Rattus norvegicus 흔적 주변에 포획트랩 을 설치하였다. 그 결과 매 차시 최소 2개체 ~ 최대 6개체가 포획되던 개체가 마지막에는 포획되지 않았다. 집쥐가 사수도에 유입된 경로는 과거 레저 및 어업을 위해 출입하는 배를 통하여 유입되었을 것으로 추정하고 있다. 2006년 집쥐로 인한 슴새의 피해가 확인된 후 철저한 경비를 통하여 사수도 출입을 엄격히 금하고 2013년 해양정화 사업과 2015년부터 지속된 포획을 통하여 구제가 성공적으로 이루어지고 있는 것으로 판단된다. 본 상태 유지 및 관리를 위해서 앞으로 새로운 집쥐의 유입을 제어하기 위하여 지속적이고 철저한 출입관리를 이어가 출입자를 엄격히 통제하는 등의 보존 관리방안이 필요하다 할 수 있다.

This study was conducted to investigate the relationship between changes of rumen microflora and bloat in Jersey cow. Jersey cows (control age: 42 months, control weight: 558kg; treatment age: 29 months, treatment weight 507kg) were fed on the basis of dairy feeding management at dairy science division in National Institute of Animal Science. The change of microbial population in rumen was analyzed by using next generation sequencing (NGS) technologies due to metabolic disease. The diversity of Ruminococcus bromii, Bifidobacterium pseudolongum, Bifidobacterium merycicum and Butyrivibrio fibrisolvens known as major starch fermenting bacteria was increased more than 36-fold in bloated Jersey, while cellulolytic bacteria community such as Fibrobacter succinogenes, Ruminococcus albus and Ruminococcus flavefaciens was increased more than 12-fold in non-bloated Jersey. The proportion of bacteroidetes and firmicutes was 33.4% and 39.6% in non-bloated Jersey’s rumen, while bacteroidetes and firmicutes were 24.9% and 55.1% in bloated Jersey’s. In conclusion, the change of rumen microbial community, in particular the increase in starch fermenting bacteria, might have an effect to occur the bloat in Jersey cow.

소에서 설사 등의 소화기질환, 폐렴 등의 호흡기질환, 유산 등의 번식장애를 유발하는 소 바이러스성 설사병(Bovine Viral Diarrhea, BVD)은 소 사육농가에서 경제적인 손실을 입히는 대표적인 생산성 저하 질병 중의 하나인데, 특히 유산, 사산 및 수태율 저하를 유 발하여 번식우 사육농가에 직접적인 피해를 입히고 있는 실정이다. 농림축산검역본부에 서는 BVD로 인해 1마리당 50,000원 정도의 손실로 연간 손실액이 최소 1천억 이상이라 고 추정하였고, 미국은 급성 BVD 감염으로 소 1마리당 약 400달러의 피해가 발생한다고 할 만큼 소 사육농가에 막대한 피해를 입히고 있지만, 우리나라에서 아직 법정 가축전염 병으로 지정되지 않아 체계적인 발생 상황이 확인되지 않고 있는 실정이다. 본 연구에서 는 한우 및 젖소 사육 농가를 대상으로 소 바이러스성 설사의 항원 양성률을 분석하여 소 바이러스성 설사병의 발생 현황을 확인하고자 하였다. 본 실험을 위해 4개도(강원, 전 북, 경남, 제주) 9개 목장에서 사육하고 있는 한우 송아지 및 젖소 육성우를 대상으로 분 변을 이용하여 PCR 방법으로 농장별, 생후 일령별 항원 양성률을 조사하였다. 한우 송아 지의 BVD 바이러스 항원 양성률을 조사한 결과 전체 조사 두수의 60.0%가 양성을 나타 내었고, 농장별로는 10.0%∼81.8%를 나타내어 농장별로 양성률에 많은 차이를 나타내었 다. 젖소 육성우의 경우 28.7% 양성률을 나타내었는데, 농가별로는 0%∼65.0%로 한우 송 아지와 마찬가지로 농장별로 차이를 보이고 있었다. 한우 송아지의 생후 일령(주령)별 양 성률을 조사한 결과 조사된 한우 송아지의 54.8%가 항원 양성률을 나타내었는데, 1주령 80.0%, 2주령 33.3%, 3∼4주령 45.5%, 5∼8주령 60.0%, 9주령 이상 50.0%를 나타내어 송 아지의 전체 연령대에 다양하게 항원 양성반응을 나타내었다. 소에서 번식장애 등의 손실 을 입히고 있는 BVD는 우리나라에서 예방백신이 개발되어 활용되고 있지만 소 사육농가 에서는 구제역 등과 같은 전염병에 비해 현실적으로 피해를 실감하지 못하고 있는 질병 이기도 하다. 따라서 본 연구 결과를 바탕으로 농가에서 임신 예정우, 송아지를 대상으로 예방백신 접종을 권장함으로써 그 피해를 경감시킬 수 있는 질병으로 사료된다.

Reproductive disorders in cows cause economic loss in livestock farms. Reproductive diseases, such as follicular cyst, luteal cyst, endometritis, pyometra, and repeat breeding cause infertility. Among these diseases, endometritis and pyometra are uterine infections that are leading causes of infertility. This study was performed to investigate the causative agents of uterine diseases using bacterial culture. Bacteria were obtained from the reproductive organs (vagina, uterine cervix, and uterine horn) of dairy cow diagnosed with endometritis or pyometra, and cultured on blood agar. The colonies obtained from cultivation for 24 hours were passaged. To identify the bacteria, the colonies grown in passaged culture Gram stained and applied to an automatic biochemical microbial identification system. Escherichia coli were commonly detected in vagina, uterine cervix, and uterine horn of dairy cows diagnosed to pyometra. The cows having endometritis showed not only Escherichia coli but also Pantoea spp. and Klebsiella spp. strains. Dairy cows that were infected with Escherichia coli in uterus caused mastitis or digestive disease. These results suggest that sanitary feeding and management beforehand are needed to prevent bacterial infections.

vThis study analyzed the coat color-related genes of MC1R, ASIP, ECA3-inversion, and STX17 of 1,462 Jeju horses administered by the Jeju Special Self-Governing Province. This was done to investigate the distributional characteristics of coat color-related genes in the Jeju horse group and the changes of its coat color-related genes by generation. The genotype frequency of the MC1R gene of E+/E+ and E+/Ee related to black coat color was 0.122 and 0.447, respectively, while Ee/Ee of the chestnut genotype was 0.429. The genotype frequency of the ASIP gene of AA/AA, AA/Aa, and Aa/Aa was 0.46, 0.448, and 0.091, respectively, where the genotype frequency of Aa/Aa turned out to be relatively low. The To/To and +/To genotype that manifests the Tobiano shape was 0.001 and 0.119, respectively, with the share of Tobiano shape around 12%. The genotype frequency of G/G and G/g of STX17 related to grey coat color was 0.002 and 0.680, respectively, with the share of grey horses among the Jeju horse group at 68.2%. As for the change of coat color genes by generation, no large changes were observed in the MC1R and ASIP genes. In ECA3-inversion, the To allele that manifests Tobiano significantly decreased following the generational change (p<0.05), while the STX17 G allele related to grey coat color significantly increased following the generational change (p<0.05). It will be necessary to examine the coat color genes when selecting breeding horses so that the diversity of coat colors among the Jeju horse group can be maintained.

본 증례는 다발성 골수종을 진단 후 Bortezomib, Melphalan, Prednisolone 항암치료 중에 급성 췌장염이 발생된 매우 드문 경우이다. 급성 췌장염이 원인을 알기 위하여 알코올 병력, 담석증, 외상, 고칼슘혈증, 고중성지방혈증 등에 대한 혈액검사 및 영상의학적 검사를 시행하였지만 특별한 소견은 없었다. 급성 췌장염을 유발할 수 있는 약제인 Bortezomib이 그 원인일 가능성으로 판단되어 Bortezomib 중단과 보존적 치료로 급성 췌장염이 호전되었다. Bortezomib은 다 양한 비특이적인 위장관 증상을 흔하게 유발할 수 있지만 복통이 지속되거나 재발하면 드물지만 급성 췌장염이 발생할 수 있음을 염두에 두어야 하겠다.

본 연구는 고온 환경에서 Yorkshire 품종의 혈액 내 전해질과 혈액학적 성분의 변화를 조사하기 위하여 실시하였다. 73 일령(BW 40.6±1.4 kg)의 Yorkshire종 10두를 공시하여 개별 pen에 1두씩 배치하였다. 시험기간은 한국에서 폭염이 시작되는 2013년 7월 24일부터 동년 9월 4일까지 6주간 실시하였다. 시험기간 중 평균온도가 가장 높은 시기는 시험 3주차(28.6℃)였으며, 최고온도는 시험 4주(32.1℃)에 관찰되었다. 일당증체량은 온도가 가장 높았던 시험 3주차부터 감소하는 경향으로 나타났다. 혈청 내 pH와 삼투압은 시험기간 동안 유의적인 변화가 관찰되지 않았다. 나트륨이온 (P<0.01)과 염소이온(P<0.05)의 농도는 시험 6주에 유의적으로 증가하였다. 일반혈액검사 분석 결과에서 혈액 내 호중구(P<0.05)와 단핵구(P=0.057)의 수준은 시험 6주에 증가하고, 헤모글로빈과 평균 적혈구 혈색소 농도는 시험 4주와 6주에 감소하는 것으로 관찰되었다(P<0.05). 혈액생화학 분석에서는 총 콜레스테롤(P<0.01), 총 단백질(P<0.001)과 혈중 요소태 질소(P<0.01)의 농도가 4주와 6주에 높아지는 것으로 관찰되었으며, glucose 농도는 6주에 유의적으로 낮아졌다(P<0.05). 본 연구의 결과는 한국의 여름철 폭염기간 동안 돼지의 체내에서 생리생화학적, 혈액학적 변화가 어떻게 변하는지에 대한 기초정보를 제시하며, 이러한 정보는 혹서기 고온 스트레스로 인한 돼지 생산성저하 방지 기술을 개발하는 데에 기초자료로 활용될 수 있을 것으로 사료된다.

The occurrence of mastitis in diary cattle has been caused by genetic, physiological, managemental and environment factors accounted for the highest percentage of worldwide disease in dairy cattle. The purpose of this study was to analyze the occurrences and causative bacteria of subclinical mastitis in milking cows and also examine the distribution of bacteria in milk by isolating and identifying bacteria both in whole milk and quarter milk. 31.4% of the milking cows suffered subclinical mastitis, and 9.5% had it in terms of quarter milk. According to the results of analyzing bacteria in quarter milk of which somatic cell count (SCC) was over 500 thousand, 15 kinds of bacteria were isolated, and among them, Pantoea spp. formed the biggest part as 15.8%. From whole milk, 37 kinds of bacteria were identified, and among them, Klebsiella oxytoca showed the highest identification rate as 30.1%. According to the results of bacteria analyzed from the quarter milk of entire milking cows, 52 kinds of bacteria were identified. Among them, 17 kinds of Staphylococci were isolated, and CNS (Coagulase-Negative Staphylococci) formed a large part as 44.9%. The findings of this study showed that various kinds of bacteria were isolated from cows having subclinical mastitis; therefore, when managing specifications about milking or such, dairy farm will have to take proper action like performing sanitary control or counting somatic cells regularly in order to do their best for reducing mastitis.

This study aimed to analyze the relationship between catch amount and market price of sandfish for improvement of fishing revenues and effective fisheries management. By estimating the sandfish price function by fishery, the study tried to investigate changes of prices by catch amount as well as changes of fishing revenues by catch amount and price. Results showed that time series data on catch and price were estimated to be non-stationary from unit root tests, but long-term equilibrium relations between catch amount and price were found from a cointegration analysis. Results of regression analyses indicated that the catch amount would have negative impacts on prices of sandfish in both coastal gillnet and danish seine fisheries.

The existing metal getters are invariably covered with thin oxide layers in air and the native oxide layer must be dissolved into the getter materials for activation. However, high temperature is needed for the activation, which leads to unavoidable deleterious effects on the devices. Therefore, to improve the device efficiency and gas-adsorption properties of the device, it is essential to synthesize the getter with a method that does not require a thermal activation temperature. In this study, getter material was synthesized using palladium oxide (PdOx) which can adsorb H2 gas. To enhance the efficiency of the hydrogen and moisture absorption, a porous layer with a large specific area was fabricated by an etching process and used as supporting substrates. It was confirmed that the moisture-absorption performance of the SiO2/Si was characterized by water vapor volume with relative humidity. The gas-adsorption properties occurred in the absence of the activation process.

Graphene oxide has been synthesized by microwave-assisted exfoliation of graphite oxide prepared by modified Hummers method. Graphite was oxidized in a solution of H2O2 and KMnO4 at 65~80˚C, followed by 10 % H2O2 solution treatment at 80~90˚C. The graphite oxide was exfoliated under microwave irradiation of 1 kW and was reduced to graphene effectively by hydrazine hydrate (H4N2·H2O) treatment. The exfoliation of graphene oxide was significantly affected by the microwave irradiation on (heating)/off (cooling) period. An on/off period of 10 s/20 s resulted in much more effective exfoliation than that of 5 s/10 s with the same total treatment time of 10 min. This can be explained by the higher exfoliation temperature of 10 s/20 s. Repetition of the graphite oxidation and exfoliation processes also enhanced the exfoliation of graphene oxide. The thickness of the final graphene products was estimated to be several layers. The D band peaks of the Raman spectra of the final graphene products were quite low, suggesting a high crystal quality.

The objective of this study was to analyze the accuracy of estrus detection of heat detector and analysis of estrus behavior (mounting and mounted), and the evaluation of conditions required for improving reproductive efficiency in Holstein dairy cows fitted with a estrous detector. The heat detection system consists of estrous detector based on wireless sensor and an electric bulletin board displayed estrus behavior data. When cow mounting other cows, the accuracy of estrus behavior displayed an electric bulletin board were 87.5% (mounting other cows only), 100% (mounting other cows but not standing), 80.0% (mounting other cows with standing for 1∼4 seconds), 90.0% (mounting other cows but not standing for 1∼4 seconds), 80% (mounting other cows with standing for more than 5 seconds) and 90.0% (mounting other cows but not standing for more than 5 seconds). When cow mounted other cows, the accuracy of estrus behavior displayed an electric bulletin board were 100% (mounted other cows but not standing), 100% (mounted other cows with standing for 1∼4 seconds), 100% (mounted other cows but not standing for 1∼4 seconds) and 100% (mounted other cows with standing for more than 5 seconds). Circadian distribution of first observed in estrus were 59.1% (am 8∼pm 6) and 40.9% (pm 6∼am 8). Distribution for the number of estrus behavior were 40.9% (less than 3 times), 36.4% (4∼6 times) and 22.7% (more than 4 times). The conception rates relative to interval from first estrus behavior to insemination for estrus periods were 23.1% (less than 11 hours) and 55.6% (12∼20 hours).

This study aimed to improve the reproductive efficiency of dairy herds by comparison and analyzing estrous appearance rate, conception and non-conception rate according to the stage of lactation using the lactation and reproductive records of average (less than 10,000 liters milk in 305 days) and high yielding (more than 10,000 liters milk in 305 days) Holstein cows (n=102). Milk production and reproduction data were collected between January 2010 and December 2012 from Holstein cows kept in the commercial dairy farms. Average (n=32) and high yielding (n=24) Holstein cows used to analyze the relationship between milk yield and reproductive performance. Our results showed that estrous appearance rate according to the stage of lactation was 25.0% (30∼59d), 40.6% (60∼ 89d), 25% (90∼110d) and 9.4% (>111d) in average yielding cows and 16.7% (30∼59d), 20.8% (60∼89d), 12.5% (90 ∼110d) and 50.0% (>111d) in high yielding cows, respectively. Conception rate according to the stage of lactation was 87.5% (30∼59d), 61.5% (60∼ 89d), 75.0% (90∼110d) and 66.7% (>111d) in average yielding cows and 25.0% (30∼59d), 0% (60∼89d), 33.3% (90∼ 110d) and 50.0% (>111d) in high yielding cows, respectively. Days between parturition and conception was 23.7% (<149d), 0% (150∼209d) and 0% (>210 d) in average yielding cows and 69.0% (<149 d), 77.8% (150∼209d) and 38.9% (>210d) in high yielding cows, respectively. Conception rate from 110 days postpartum in high yielding cows was 41.7% (110∼150d), 50.0% (151∼180d) and 50.0% (>181d). Body condition score (BCS) in 120 days postpartum was 2.64±0.1 in average yielding cows and 2.28±0.1 in high yielding cows, respectively.

The objective of this work was to analyze the concentrations of progesterone (P4) and estrogen (E2) hormones changed during estrus synchronization in dairy heifers. Estrus synchronization was carried out with CIDRⓇ (Controlled Intravaginal Drug Release) devices. Corpus luteum (CL) was classified into three grades based on its size and palpable characteristics. The concentrations of P4 and E2 were measured by enzyme-amplified chemiluminescence. Serum P4 concentration was markedly low at the estrus stage (36 hrs after removal of CIDR) compared to other stages, while E2 concentration was kept high during estrus stage. The serum P4 concentration was highest in the CL classified into gradeⅠ. These results indicate that P4 concentration could be used as a criteria for determining recipients for artificial insemination or embryo transfer in dairy cattle.