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        검색결과 369

        1.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: The biological information of fish, which include reproduction, is the prerequisite and the basis for the assessment of fisheries. Methods: The aim of this work was to know the reproductive biology with the first sexual maturity (TL50) and the spawning period for 58 mainly fish species in the waters around La Réunion Island (Western Indian Ocean). Twenty families belonging to the Actinopterygii were represented (acanthuridae, berycidae, bramidae, carangidae, cirrhitidae, gempylidae, holocentridae, kyphosidae, labridae, lethrinidae, lutjanidae, malacanthidae, monacanthidae, mullidae, polymixiidae, pomacentridae, scaridae, scorpaenidae, serranidae, sparidae; 56 species; n = 9,751) and two families belonging to the Elasmobranchii (squalidae, centrophoridae; 2 species; n = 781) were sampled. Between 2014 and 2022, 10,532 individuals were sampled covering the maximum months number to follow the reproduction periods of these species. Results: TL50 for the males and the females, respectively, ranged from 103.9 cm (Acanthurus triostegus ) to 1,119.3 cm (Thyrsitoides marleyi ) and from 111.7 cm (A. triostegus ) to 613.1 cm (Centrophorus moluccensis ). The reproduction period could be very different between the species from the very tight peak to a large peak covered all months. Conclusions: Most species breed between October and March but it was not the trend for all species around La Réunion Island.
        4,000원
        2.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Reproductive management practices play crucial roles to maximize the reproductive performance of cows, and thus contribute to farm profitability. We aimed to assess the reproductive management of cows currently practiced in the dairy farms in an urban farming system. Methods: A total of 62 dairy farms were randomly selected considering all size of farms such as small (1-5 cattle), medium (6-20 cattle) and large farms (> 20 cattle) from selected areas of Dhaka city in Bangladesh. The reproductive managementrelated parameters viz. estrus detection, breeding method, pregnancy diagnosis, dry cow and parturition management, vaccination and treatment of reproductive problems etc. were obtained in a pre-defined questionnaire during the farm visit. Results: The visual observation method was only used (100.0%; 62/62) for estrus detection irrespective of size of the farms; while farmers observed cows for estrus 4-5 times a day, but only for 20-60 seconds each time. Regardless of farm size, 89.0% (55/62) farms used artificial insemination (AI) for breeding the cows. Intriguingly, all farms (100.0%) routinely checked the cows for pregnancy at 35-40 days post-breeding using rectal palpation technique by registered veterinarian. However, only 6.5% (4/62) farms practiced dry cow management. Notably, all farms (100.0%) provided nutritional supplements (Vit D, Ca and P) during late gestation. However, proper hygiene and cleanliness during parturition was not practiced in 77.4% (48/62) farms; even though 96.7% (60/62) farms treated cows by registered veterinarian for parturition-related problems. Conclusions: While farmers used AI service for breeding and timely check their cows for pregnancy; however, they need to increase observation time (30 minutes/ observation, twice in a day: early morning and early night) for estrus detection, consider dry cow management and ensure hygienic parturition for maximizing production.
        4,000원
        3.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 낙지의 생식생태 이해에 필요한 수컷 생식기관과 정포의 미세해부학적 구조를 기재 하였다. 낙지는 교접완의 유무를 통하여 성을 구별할 수 있는 성적이형을 갖는 종이다. 수컷 생 식기관은 정소, 일차수정관, 저정낭, 이차수정관, 정포선, 정포낭으로 구성된다. 정소는 조직학 적으로 정세관형이었으며, 수컷 생식세포들은 층상배열상을 보였다. 일차수정관은 정소와 저정 낭을 연결하는 관으로 상피층과 결합조직으로 이루어져 있었다. 저정낭은 일차수정관과 이차 수정관의 사이에 위치하며, 상피층은 상피세포와 점액세포로 구성된다. 점액세포는 AB-PAS (pH 2.5) 반응에서 푸른색, AF-AB (pH 2.5) 반응에서 보라색으로 반응하였다. 이차수정관은 저정낭 과 정포선을 연결하는 짧은 관으로 내강에 주름이 발달하였다. 정포선은 다수의 관상선으로 이루어져 있었으며, 분비세포는 호산성 과립을 가지고 있었다. 정포낭은 주머니 모양으로 내강 에 주름이 발달하였으며, 상피층에 공포상의 분비세포가 존재하였다. 정포는 길이 약 83.5 mm 로 전방부의 당김사, 중간부의 발사체와 고정체, 후방부의 정자 저장부로 구성되어 있었다.
        4,000원
        5.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: The potential impact of aqueous extracts from Psidium guajava leaves on the reproductive system of female rabbits was evaluated. Methods: Twenty-eight rabbits, aged five to six months were utilized. Rabbits were divided into four groups and were randomly assigned to receive one of the following oral doses of the guava leaf extracts: 0 (control group), 10, 20, or 30 mg/kg of body weight. After a treatment period of 30 days, blood was collected via jugular venipunture and the serum was extracted for the assessment of serum biochemical traits levels. The females were bred and monitored throughout their pregnancy to ascertain reproductive outcomes. Results: The results indicated that the guava leaf extract significantly increased the body weight of the rabbits during both pre- and post-pregnancy compared to the control group (p < 0.05). The litter size at three weeks post-birth, prolificity rate, FSH, LH, and protein levels were notably higher (p < 0.05) at a dose of 20 mg/kg of body weight. The viability rate three weeks post-birth increased with escalating extract doses, and the highest values were observed at doses of 20 and 30 mg/kg of body weight (p < 0.05). Conclusions: This study demonstrated that, the aqueous extract of guava leaves appears to stimulate the production of FSH, LH and enhance body weight, prolificity, and pregnancy outcomes in mammals. As such, it is suggested that a dose of 20 mg/kg body weight could be beneficial in improving the reproductive performance of female.
        4,000원
        6.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        연구에서는 두족류의 생식생태를 이해하기 위하여 우리나라 주요 두족류인 살오징어 Todarodes pacificus 수컷의 생식기관과 정포의 미세해부학적 구조를 기재하였다. 살오징어는 자웅이체로 외투막에 투과되는 생식기관의 색과 교접완을 통하여 암, 수를 구분할 수 있는 성 적이형을 가진다. 수컷 생식기관은 정소, 1차 수정관, 정포선, 정포낭, 2차 수정관으로 구성된다. 살오징어의 수컷은 정포 형성기관인 정포선과 같은 특수화된 생식기관을 가진다. 정소는 조직 학적으로 정세관형이었다. 1차 수정관은 정소의 후방부터 정포선까지 연결된 가늘고 긴 역삼 각형의 용수철 형태였다. 내부에는 H-E 염색에서 호염기성으로 반응하는 정자가 가득 차 있었 다. 정포선은 1차 수정관과 정포낭에 연결된 불규칙한 타원형으로 내부에는 다수의 관상선이 존재하였다. 정포낭은 정포선과 2차 수정관 사이에 위치하는 관 구조로 내강에서는 다수의 정 포가 확인되었다. 2차 수정관은 정포낭의 후방부에 연결되며, 내부에 정포를 갖고 있었다. 정포 는 길이 약 22 mm의 길고 투명한 관 형태로 내부에는 정자 덩어리를 갖고 있었다.
        4,000원
        7.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The impact of heat stress (HS) on reproductive performance and its problems in cows remains to be investigated in Bangladesh. The study was, therefore, aimed to evaluate the effect of HS on fertility and reproductive health problems of dairy cows in a selected area of Bangladesh. A total of 1,095 cows from 500 farms were included in this study. The climate-related data were recorded daily basis for every month in a year and temperature-humidity index (THI) values were calculated to determine the level of HS. Concurrently, data on fertility parameters [number of services per conception (NSC), conception rate (CR) and calving to the first service interval (CFSI)], and reproductive problems were collected through a pre-defined questionnaire. The results show that crossbred [Native x Holstein-Friesian, (HF)] cows were more vulnerable (p < 0.05) to a magnitude of HS effects considering physiological parameters of cows [age, body condition score (BCS), parity and milk yield]. Regarding fertility, HS had no effect on NSC, CR and CFSI in both native and crossbred cows (p > 0.05). The findings on the reproductive problems indicate that HS had significant influence on the prevalence of anestrus (χ2 = 21.814, p < 0.05) and retained placenta (χ2 = 24.632, p < 0.05) in cows. Of note, the prevalence of repeat breeding syndrome was 2.5 folds higher in stress condition than in no stress condition. Abortion and dystocia were not influenced by HS. In conclusion, HS does not influence the fertility parameters of cows studied; however, anestrus and retained placenta are likely to occur under HS conditions in cows.
        4,000원
        11.
        2022.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        열대거세미나방(Spodoptera frugiperda)(밤나방과) 유충 사육을 위해 이전에 개발된 두 인공사료(N4와 N6)가 뒷흰가는줄무늬밤나방 (Mythimna loreyi)(밤나방과) 사육에도 적합하였다. 실험실 조건[25°C, 15:9 h (명:암) 광주기]에서 알기간은 4.9–5.2일, 유충기간은 22.3-23.2일로 두 사료 집단 사이에 큰 차이가 없었다. 한 사료 집단 내에서 번데기 기간은 암컷이 약 12.6-12.8일, 수컷이 14.1–14.5일이었고, 번데기 무게는 암컷 이 약 345 mg, 수컷이 약 380 mg로, 암수 사이에 유의한 차이를 보였다. 유충의 용화율과 용의 우화율은 각각 91-94%와 91-95%로 두 사료집단 사 에의 유의한 차이를 보이지 않았다. 성충 산란전 기간은 3.4일, 산란기간은 약 4.7-4.8일 이었다. 성충 수명은 암컷이 8.2일, 수컷이 10.3-12.4일로 수컷의 수명이 길었다. 암컷당 부화한 총 자손 수는 724-847마리였고, 최대 약 1,400마리였다. 생명표 분석에서 개체군 내적자연증가율(N4 집단 0.1181, N6 집단 0.1253)은 두 사료집단 사이에 유의한 차이가 없었다. 한 사료집단 내에서 유충 영기가 5령 혹은 6령까지 발육하는 개체변이가 발 견되었다. N4 사료집단의 5령 개체 비율(약 22%)은 N6 사료집단의 5령 개체비율(약 7%)보다 높았다. 6령 개체들의 평균 유충기간이 5령 개체들보 다 더 길었다. 유충의 영기별 두폭은 1령의 약 308 μm부터 6령의 약 3,065 μm까지, 몸길이는 1령의 약 2.0 mm부터 6령의 약 29.1 mm까지 측정 되었다. 2020년 6-7월 중에 옥수수 포장에서 뒷흰가는줄무늬밤나방 유충이 동속종인 멸강나방(M. separata) 유충과 함께 발견되었다.
        4,300원
        12.
        2022.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 LED 조명의 파장이 육용종계의 생산성, 번식호르몬, 면역 수준 및 행동에 미치는 영향을 확인하고자 실시하였다. 25주령 아바에이커 192수를 공시하였다. 처리구는 백색(5,000 K), 녹색(520 nm), 황색(570 nm) 및 적색(620 nm) LED 전구를 사용하여 처리구당 6반복, 반복당 8수씩 임의 배치하였으며, 15주간 사양실험을 실시하였다. 산란율은 적색 처리구에서 유의적으로 증가하였고(P<0.05), 난중은 적색 처리구에서 유의적으 로 감소하였다(P<0.05). 수정율, 부화율, 병아리 체중, IgG 수준 및 혈액 생화학 조성은 처리구 간에 통계적인 차이가 없었다. 번식호르몬인 FSH와 LH 농도는 적색 LED 처리구에서 현저히 높게 나타났다(P<0.05). 또한 행동 관찰 결과, 적색 처리구에서 바닥 긁기, 바닥 쪼기 및 깃털 쪼기 행동이 다른 처리구에 비해 유의적으로 높게 나타났다(P<0.05). 본 연구 결과, 육용종계에 LED 점등을 사용할 경우 적색 처리구에서 번식호르몬의 증가와 산란율이 높아지는 것을 확인하였다. 그러나 적색 처리구에서 바닥 긁기, 바닥 쪼기 및 깃털 쪼기 행동이 높게 나타난 원인을 밝히기 위한 추가 연구가 필요한 것으로 보인다. 따라서 산란성적, 번식 호르몬 분비를 고려할 때 육용종계에 적색 LED 조명이 유리하다는 것을 확인할 수 있었다.
        4,000원
        13.
        2022.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to provide information about annual variations in catch size and changes in reproductive biology in the common octopus, Octopus vulgaris, a commercially important species in Jeju Island. Samples were collected from coastal waters of Jeju Island, Korea by coastal trap fishery from January to November 2021. Octopus vulgaris have been decreasing in this region since 1984. The mantle length (ML) ranged from 4.5 to 17.8 cm and body weight (BW) ranged form 88.5 to 2,657.5 g. A χ 2 -test revealed that the number of males was significantly greater than females (χ 2 = 32.712, df = 10, P<0.05). Mature females were found from January to July and male occurred January to August. The gonadosomatic index value was higher from July to August than other months. The relationship between mantle length and body weight was BW = 2.4527ML 2.3139 (female) and BW = 2.6785ML 2.3159 (male). At 50% group maturity, female and male average weight was estimated to be 554.7 g and 330.6 g, respectively.
        4,000원
        14.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        도시 생태계에서 우점 수종의 형질 특성은 분획화 및 고립된 식생, 그리고 생물상호작용 감소 등 환경 변화에 대한 종의 형질 적응과 생태계 기능에 대한 통찰력을 제공한다. 우리는 한국의 서울 중심에서 남쪽 방향의 4개 산지에서 환경 요인 (지리, 기상 및 토양 속성)을 포함하여 모두 40개체 팥배나무 (Sorbus alnifolia)에서 측정한 4개 유형의 잎 형질 (Leaf area, Specific leaf area, Leaf dry mass content, Leaf shape index)과 7개 유형의 번식 형질 (Fruit width, Fruit length, Fruit shape, Fruit dry weight, Fruit dry matter content, Seed weight 및 Seed ratio)의 평균과 분산 양상, 그리고 형질 조합에 대한 다변량 분석을 실시하였다. 측정된 환경 요인은 조사 장소의 개별성을 나타내었지 만, 도심 식생이 더 건조하고 생장도일이 길었다. 도심에서 팥배나무의 잎은 작고 무거워지며, 열매는 길쭉하고 가벼운 종자를 생산하여, 오랜 도시화 영향에 따른 형질 반응들이 관찰되었다. 우리의 연구는 식생 파편화 및 고립화에 따른 생물 상호작용 감소를 나타내는 도심 환경에서 팥배나무 집단의 성장 및 번식 기제의 변화를 확인하였다. 우리는 축소된 생물 상호작용 규모, 그리고 대기 오염 같은 부정적 환경 요인이 많은 도시에서 핵심 수종의 기능과 지속성에 관해 제한적이지만 뚜렷한 생태 정보를 제공한다.
        4,800원
        16.
        2021.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study analyzed the reproductive biology, fishing characteristics and changes in fishing business of Liparis tanakae, snailfish collected from September to March. It was the period when they were mainly caught from 2018 to 2020. The average length was generally small in September and October and was large in January and February. The average body weight was generally around 1,500 g and the average body weight in autumn was lower and in winter was higher. The sex ratio of male and female was 0.40:0.60 (χ 2 test, p < 0.05). The spawning period was estimated from October to February and the main spawning period was from December to February through the GSI. The egg diameter of matured staged female L. tanakae was 0.11-1.48 mm, which was the main spawning period and the relationship between body weight and fecundity was F = 1849TL0.1093 (r2 = 0.2401). The monthly catch of L. tanakae was high from November to February, the time of migrating to the coastal area. Coastal gillnet fishery showed the highest percentage of all fisheries catching Liparis spp. Liparis spp. were caught at a high rate in winter in Chungnam, Jeonbuk, Jeonnam and Gyeongnam region, and revenue and cost was increased since 2017. Assuming a situation where there is no catch of Liparis spp., the fishing profit that can be obtained was the highest in Gyeongnam region and the dependence on fishing of Liparis spp. by coastal gillnet fishery was high.
        4,600원
        17.
        2021.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        번식효율은 농가수입에 직접적으로 영향을 미치는 요인으로 암소뿐 만 아니라 씨수소의 번식효율은 중요한 경제형질로 여겨지고 있다. 본 연구에서 는 한우 씨수소에 대한 번식효율을 분석하기 위하여 2010~2017년에 전북지역 분만기록 62,284개와 이에 사용된 132두의 KPN에 따른 인공수정 수태율을 분석하였다. 종부차수(NAIPC)가 증가함에 따라 분만간격(CI), 공태기간(CCI)이 유의적으로 증가하였으며(P<0.05), 임신율은 낮아졌다. 첫 종부 임신율은 62.365%로 나타났으나, 3차 이후에는 48.147 이하로 급격히 낮아졌으며, 6차 이후에는 15.664% 이하로 낮아졌다. KPN과 인공수정사 모두 수태율에 크게 영향을 미치는 것으로 나타났다. KPN에 따른 수태율은 39.154~70.621%로 분석되었으며, 인공수정사에 따른 수태율 은 22.237~85.517%로 나타났다. 인공수정 실패 시 같은 KPN의 재사용율은 20% 내외로 특별한 경향은 보이지 않았다. 첫 종부 기록만을 이용하여 상대적 추정 수태율(ESCR)을 분석한 결과 KPN1041이 가장 높은 11.107%로 나타났으며, KPN1112는 가장 낮은 -20.591%로 나타나 31.698%의 차이를 보였다. 본 연구결과 인공수정사 뿐 만 아니라 전북지역에서 사용되고 있는 KPN에 따라 번식효율이 크게 영향 받을 수 있는 것으로 나타났다.
        4,000원
        18.
        2020.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The present study was conducted to investigate the effect of environmental temperature and backfat thickness (BT) on the reproductive performance of lactating sows. Sixty crossbred sows were allotted to four groups in a 2×2 factorial arrangement by environmental temperature (high temperature [HT], 27.5±1.76℃; low temperature [LT], 23.3±0.89℃) and BT (<20 mm, average 17.70 mm; ≥20 mm, average 23.20 mm) from July to August 2019. Sows in the HT group experienced a greater change in BT and a lower feed intake. Losses in body weight and BT were lower in sows with <20 mm BT than in those with ≥20 mm BT. Sows with low BT had a lower weaning-to-estrus interval than sows with high BT (5.20, 4.93 d vs. 5.87, 5.60 d, respectively). Piglet survivability was lower in the HT group (90.31%) than in the LT group (94.87%). Piglet weaning weight and average daily weight gain were greater in sows with <20 mm BT (5.75 kg and 201.46 g, respectively) than in those with ≥20 mm BT (5.49 kg and 188.41 g, respectively). Sows in the HT group had higher cortisol concentrations than those in the LT group (post-farrowing: HT 7.86 μg/mL vs. LT 6.04 μg/mL; weanling: HT 5.48 μg/mL vs. LT 4.40 μg/mL). In conclusion, environmental temperature adversely influenced sow performance and cortisol levels. Moreover, sows with low BT had a greater weaning-to-estrus interval when subjected to heat stress.
        4,000원
        19.
        2020.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Purpose: The purpose of this study was to understand the reality of the suffering as infertile women who are doing repeated ART (Assisted Reproductive Technology) for pregnancy and childbirth. Methods: The data were analyzed using Colaizzi’s (1978) phenomenological method. Nine women receiving repetitive ART participated in semi-structured, in-depth interviews for this study. Results: Data analysis yielded sixteen themes which were grouped into four theme clusters: ‘Being demoted to a tool only for pregnancy’, ‘Struggling for the happiness hard to get’, ‘Standing loneliness alone on a solitary island’, and ‘Ongoing yearning for recognition by pregnancy and childbirth’. Conclusion: The findings provide further understanding of complex experiences of women receiving ART who were struggling with practical, psychological, and relational issues in their everyday lives. Based on the results of this study, health professionals are urged to support those women receiving repetitive ART by providing comprehensive caring programs that employ personal, social, and psychological approaches so that they can resolve such issues.
        4,800원
        20.
        2020.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of the current study was to compare the effects of season and breed on the reproductive performance of male and female sheep using 12 rams and 318 ewes of Assaf and Awassi breeds under the seasonal environmental condition of United Arab Emirates for two years. The blood level of testosterone hormone was measured monthly. Semen was collected twice a month from each male using artificial vagina and evaluated for volume, motility, livability, abnormality and concentration. The scrotal circumference and thickness as well as the left testicular length, width, height and volume were measured at one-month intervals. The level of testosterone in Assaf breed was significantly higher in autumn than winter and summer. The scrotal circumference and thickness as well as the left testicular length were significantly higher in Assaf breed than Awassi breed. While, left testicular width and volume were significantly higher in Awassi breed than Assaf breed. Scrotal circumference which was higher in spring and summer than in autumn and winter season in both breeds. The SCC of semen was significantly higher in autumn than in other seasons in both breeds. The sperm abnormality was significantly higher in summer than other seasons in both breeds. The livability was significantly lower in summer in both breeds. Fecundity and prolificacy were significantly higher in Assaf than Awassi breed during autumn season. Assaf breed showed the superior reproductive performance in the autumn season when compared with Awassi breed in the same season and other seasons. The Assaf breed tolerated the climatic conditions in UAE and kept the litter size of 1.72 in comparison to Awassi breed which showed litter size of 1.09. in conclusion, the results showed the superiority of Assaf over Awassi breed and offer a good model of breeding with increased fecundity and prolificacy specially in autumn season.
        4,000원
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