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        검색결과 561

        1.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The physiological functions of the ovary and development of the corpus luteum occur through the activation of endocrine hormones. In this process, estrogen, a reproductive hormone, is secreted in the ovarian follicle and corpus luteum and affects corpus luteum formation and regression. Estrogen controls the synthesis of reproductive hormones by binding to estrogen receptor–α and –β. Estradiol–17β, synthesized in the ovary, regulates the physiological function of the corpus luteum and the angiogenesis signaling pathway. Estrogen controls progesterone synthesis, which is regulated by StAR-transported cholesterol, P450scc-converted pregnenolone in mitochondria, and 3β-HSD-synthesized progesterone in the smooth endoplasmic reticulum. Estrogen secretion is also stimulated by kisspeptin and regulated by gonadotropin-releasing hormone, follicle-stimulating hormone, and luteinizing hormone. Moreover, the formation of the corpus luteum is closely regulated by angiogenesis. VEGF is an important factor in angiogenesis and plays a role in the survival, proliferation, and migration of endothelial cells. Especially, VEGF–A is a key factor in the physiological functions of endothelial cells. VEGF binds VEGFR–2 and affects the signaling pathways of PI3K, Akt, MAPK, and ERK. Also, VEGF binds to HIF–1α, inducing VEGF secretion. Estrogen promotes the activation of HIF–1α, while the activation of mTOR and Akt stimulates VEGF secretion. Therefore, estrogen is a major reproductive hormone in physiological function and the synthesis and secretion of endocrine hormones in the ovary and corpus luteum.
        4,000원
        2.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Weaning stress is the most common issue in weanling pigs, and increases diarrhea and mortality. Various wavelengths of light irradiation affect the body owing to the association with biophotons. Biophotons are very weak photons in the visible light range generated during metabolic and chemical reactions in vivo. Immune mechanisms are activated by increasing signal transmission between cells through biophoton emission. This study evaluated the influence of ultra-weak light (LED) on growth performance, antioxidant status, and stress of weaned piglets. A total of 120 weaned pigs with an average initial body weight of 7.04±0.01 kg (age: 21 d) were allotted to two treatments (Control and LED) with 10 replicates. Diets prepared in pellet form were administered to the pigs in three phases including Phase 1 (0–14 d), Phase 2 (15–28 d), and Phase 3 (29–42 d). At the end of the study, the average daily gain (8.96%, p<0.05) and feed efficiency (6.56%, p<0.05) of pigs was significantly increased at phase 3 in the LED treatment. Low concentration of malondialdehyde (12.58%, p<0.05) and high concentrations of glutathione reductase (7.41%, p<0.01) and total antioxidant capacity (5.48%, p<0.05) were observed in the LED treatment at Day 42. The concentration of hair cortisol was also decreased (24.05%, p<0.05) in the LED treatment at Day 42. In conclusion, the use of LED for weanling pigs is recommended to improve growth performance by modulating antioxidant capacity and cortisol level in hair.
        4,000원
        3.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Black soldier fly (BSF, Hermetia illucens) has been noted as an excellent feed ingredient. However, there is limited information on rearing and processing technology. Thus, this study was conducted to evaluate the substrates for rearing BSF and the optimal processing method for BSF performance. Study separated as 2 experiment, BSF rearing and drying method(Exp 1.) and EP-processing method(exp 2.). During the study, 30 clutches were reared, with 10 per substrate. Three substrates, namely food waste (FW), tofu by-product (TF), and vegetable waste with two drying methods, namely hot air dry (AD) and microwave dry (MW) at expanding (EP) ratios of 5:5 and 7:3, were examined by evaluating their rearing performance, nutrient contents, in vitro digestibility and lipid oxidation stability during storage (0, 14 and 28 days). In experiment 1, the rearing substrates and drying methods were evaluated. Compared with that of conventional methods (FW, AD), the TF substrates and MW method showed higher dry matter contents (3.43%) and in vitro digestibility (1.62%) but lower ether extract contents(3.53%; p<0.05). However, the malondialdehyde (MDA) concentration under MW treatments decreased during storage (5.77%, 4.69% and 3.24%; p<0.05). In experiment 2, compared with that of the 7:3 EP-BSF ratio, the 5:5 EP-BSF ratio showed higher in vitro digestibility (2.70%) and lower MDA concentration during storage (19.19%, 7.96% and 6.42%; p<0.05). In conclusion, the optimal conditions for BSF rearing and ensuring product quality were TF substrates, MW methods and a 5:5 corn:BSF ratio. Therefore, the optimal conditions for producing EP-BSF can present an excellent feed ingredient alternative for swine feed.
        4,000원
        4.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to investigate the effects of amino acid complex additives, such as protected vitamin C (VC) or detoxified sulfur (DS), on the growth and metabolism of Hanwoo cattle under high-temperature conditions. Accordingly, farms in Temperature-Humidity Index (THI) regions ranging from 78 to 89 for over 100 days were selected. The experimental groups were control, T1 (lysine + methionine + VC, 50 g/head/day), and T2 (lysine + methionine + DS, 50 g/head/day) with 70, 77, and 71 animals each. The range of the THI for 115 days was 78-89, and this occurred in most of the experiment days. The results showed that there was no significant difference in rectal temperature among the groups. The body weight increased to 786.4 and 809.0kg in the T1 and T2 groups, respectively, compared to the control group (p<0.05). Linoleic acid showed a high result of 2.01% in the T1 group compared to the control group (p<0.05). Unsaturated fatty acids were higher at 55.70 and 56.54% in the T1 and T2 groups, respectively, compared to the control group (p<0.05), and the omega 6/3 ratio was reduced to 20.10% (p<0.05). These findings indicate that T1 has a positive impact on growth, meat quality, and fatty acid composition compared to the control group. In conclusion, amino acid complex with VC improved the body weight of Hanwoo steers and the unsaturated fatty acids and essential amino acids of their meat; however, further research is needed to clarify this impact on carcass performance.
        4,800원
        5.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        γ-aminobutyric acid (GABA) is a natural stress-reducing substance and is actively used as a human health supplement. However, minimal research has been conducted on its use in cattle. This study was conducted to evaluate the effects of GABA on the growth performance, complete blood count, blood metabolites, and carcass characteristics of fattening Hanwoo steers. Twenty-one fattening steers were randomly assigned to one of three treatments: control (basal diet: concentrate feed + rice straw), T1 (basal diet + GABA supplement at 0.8% of feed/head/day), and T2 (basal diet + GABA supplement at 1.6% of feed/head/day). Feed intake and conversion ratio did not differ among the treatments. However, the average daily gain during the early fattening period increased linearly to 0.80 kg, 0.86 kg, and 0.92 kg in the control, T1, and T2 groups (p<0.05). Plasma γ-glutamyl transferase (37.5, 58.2, 42.8 U/ℓ) and creatinine (1.32, 1.34, 1.49 ㎎/㎗) levels in the GABA supplement group were increased compared to those in the control group. The carcass weight (422.7, 427.1, 454.1 kg), rib eye area (86.67, 92.57, 91.14 cm2), and marbling score (3.67, 4.29, 4.14) were numerically higher in the GABA supplement group than in the control group. Thus, GABA supplementation positively affected the average daily gain and carcass characteristics of Hanwoo steers. However, the effect of the GABA supplement level of GABA was small, and further research using rumen-protected coating technology on GABA is necessary.
        4,000원
        6.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of this study was to prepare rice straw silage using cabbage by-product and persimmon peel which are agricultural by-products produced during the same season in Korea. The treatments comprised a commercial corn silage as the control and four rice straw silages (P15-1, P15-2, P30-1, and P30-2) with different levels of persimmon peel supplementation (15%, 30%) and ensiled periods (1 or 2 months). The cabbage by-products were used to adjust silage moisture (approximately 65%). The quality of the experimental silages was evaluated based on organic acid content, palatability to three Holstein dairy cows, and manufacturing cost. In the corn silage, all chemical compositions, except total digestible nutrients and levels of lactic and butyric acids, were significantly (p<0.05) higher than those of the rice straw silages. However, considering the quality analysis using Flieg's score, the rice straw silage supplemented with 30% persimmon peel ensiled for 2 months (P30-2) was estimated as second grade to corn silage, and was relatively better in palatability to dairy cows than the other rice straw silages, which were considered third grade. The manufacturing cost of rice straw silages using cabbage by-product and persimmon peel compared to that of corn silage was reduced by 28%. Consequently, to prepare rice straw silage adjusted to 65% moisture using only cabbage by-products without inoculant, 30% of persimmon peel, 10% of ground corn, and 2% of molasses as a sugar source should be ensiled for at least 2 months.
        4,000원
        7.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to investigate the effect of Liriope platyphylla and organic acids on enteric methane mitigation in goats using an open-circuit simplified respiration chamber system. Methane recovery was evaluated by injecting 3% standard methane gas for 30 min at 3 L/min. The percentage of methane recovery from the four chambers was 99±5.4%. Following the recovery test, an animal experiment was conducted using eight castrated Boer goats (body weight 46.6±7.77 kg) using a 2×2 crossover design. Experimental diets were as follows: 1) Control (CON), commercial concentrate and tall fescue, and 2) Treatment (MIX), concentrate supplemented with L. platyphylla and organic acids and tall fescue. Goats were offered feed at 2% of body weight (dry matter basis) in equal portions twice daily at 8:00 and 15:30. The goats were adapted to the feed and methane chamber for 10 and 3 days, respectively. Methane emission was measured one day per goat using tunable diode laser absorption spectroscopy, and temperature and airflow measurements were used to estimate methane emissions. Dry matter intake (DMI), body weight, and methane emission were measured during each period. Methane production with CON and MIX was 24.48 and 22.68 g/d, respectively, and 26.81 and 24.83 g/kg DMI, respectively. Although the differences were not significant, the use of supplements resulted in a numerical reduction in methane in MIX compared with CON. Collaboration with experts in other areas, including various engineering departments, is imperative to measure methane emissions using a chamber system accurately.
        4,300원
        8.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        On pig farms, the highest mortality rate is observed among nursing piglets. To reduce this mortality rate, farmers need to carefully observe the piglets to prevent accidents such as being crushed and to maintain a proper body temperature. However, observing a large number of pigs individually can be challenging for farmers. Therefore, our aim was to detect the behavior of piglets and sows in real-time using deep learning models, such as YOLOv4-CSP and YOLOv7-E6E, that allow for real-time object detection. YOLOv4-CSP reduces computational cost by partitioning feature maps and utilizing Cross-stage Hierarchy to remove redundant gradient calculation. YOLOv7-E6E analyzes and controls gradient paths such that the weights of each layer learn diverse features. We detected standing, sitting, and lying behaviors in sows and lactating and starving behaviors in piglets, which indicate nursing behavior and movement to colder areas away from the group. We optimized the model parameters for the best object detection and improved reliability by acquiring data through experts. We conducted object detection for the five different behaviors. The YOLOv4-CSP model achieved an accuracy of 0.63 and mAP of 0.662, whereas the YOLOv7-E6E model showed an accuracy of 0.65 and mAP of 0.637. Therefore, based on mAP, which includes both class and localization performance, YOLOv4-CSP showed the superior performance. Such research is anticipated to be effectively utilized for the behavioral analysis of fattening pigs and in preventing piglet crushing in the future.
        4,000원
        9.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted with the aim of confirming the impact and relative contribution of extreme weather to dry matter yield (DMY) of silage corn in the central inland region of Korea. The corn data (n=1,812) were obtained from various reports on the new variety of adaptability experiments conducted by the Rural Development Administration from 1978 to 2017. As for the weather variables, mean aerial temperature, accumulated precipitation, maximum wind speed, and sunshine duration, were collected from the Korean Meteorological Administration. The extreme weather was detected by the box plot, the DMY comparison was carried out by the t-test with a 5% significance level, and the relative contribution was estimated by R2 change in multiple regression modeling. The DMY of silage corn was reduced predominantly during the monsoon in summer and autumn, with DMY damage measuring 1,500-2,500 kg/ha and 1,800 kg/ha, respectively. Moreover, the relative contribution of the damage during the monsoons in summer and autumn was 40% and 60%, respectively. Therefore, the impact of autumn monsoon season should be taken into consideration when harvesting silage corn after late August. This study evaluated the effect of extreme weather on the yield damage of silage corn in Korea and estimated the relative contribution of this damage for the first time.
        4,300원
        10.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We aimed to investigate the effect of environmental enrichment via toys on the behaviour and performance of weanling pigs. A total of 300 pigs (LYD) were housed in different pens with ten pigs per replicate and ten pigs per head divided into 3 groups. Group 1 was called “CON” and received no toys, group 2 was TOY-2, and pigs in this group had access to toys in the first 2 weeks, and lastly, pigs in TOY-4 were given toys in the fourth week. The pigs had access to feed and water ad-libitum. The individual pig behaviours in each group was recorded on days 14 and 28 (d 14 and 28) with a video camera for accuracy. The results showed higher (p<0.05) overall ADG in TOY-4 compared with CON, while the overall ADFI was higher (p<0.05) in TOY-supplemented groups compared to CON. Diarrhea incidence and fecal score were lower on D 14 in TOY-supplemented groups compared with CON. Behavioural features such as ear biting and fighting were lower (p<0.05) in TOY-supplemented groups compared with CON on D 14. Tail biting was lower (p<0.05) in TOY-2 compared with CON at D 14. Conversely, at D 28, tail biting was lower (p<0.05) in TOY-4 compared with CON. The ADG improved due to the toy supplied to reduce undesirable social behaviours. We concluded that the environmental enrichment of pens with toys can help to improve the welfare in weaning pigs, leading to a greater survivability and more production thereby improving farmer incomes.
        4,000원
        11.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the relationship between service quality factors, customer satisfaction, and reuse intention based on the degree of attachment to companion animals felt by caregivers when using dog grooming services. An online and offline survey with caregivers experienced in dog grooming services were conducted, and 304 responses were analyzed using SPSS 26.0 Statistics Program. The analysis revealed the following. First, sub-factors of dog grooming service quality: empathy, assurance, tangibles, and reliability, significantly affect customer satisfaction. Second, customers satisfaction with dog grooming services significantly affects their reuse intention. Third, only reliability demonstrates a moderating effect on attachment to companion dogs in influencing the relationship between customer satisfaction and service quality. These findings that service quality management is necessary to improve the business performance of dog-grooming services. Particularly, this study is meaningful in presenting the direction of service marketing centered on trust, as more guardians consider companion dogs as family.
        4,000원
        12.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 우리나라에서 수수-수단그라스 교잡종 (sorghum bicolor L.: SSH)에 대해 극단기상과 정상기상 간 생산량을 비교할 목적으로 수행하였다. SSH 데이터 (n=1,025)는 농촌진흥청의 신품종 적응성 실험보고서(1979 ―2019)로부터 수집하였다. 기상자료는 기상청으로부터 평균기온, 최저기온, 최고기온, 최대 강수량, 누적 강수량, 최대풍속, 평균풍속 및 일조시간을 10일 기준으로 계산하 여 수집하였다. 극단기상과 정상기상 간 구별을 위해 상 자 그림을 이용하여 탐색하였다. 극단기상과 정상기상 간 생산량 차이는 5% 유의수준 하에서 t-검정 및 ANOVA를 통해 확인하였다. 그 결과, 극단기상은 극단적으로 강한 바람을 동반한 봄 가뭄, 극단적으로 높은 강우량을 기록 하는 여름장마와 가을장마가 두드러졌다. 예측 생산량 피 해(kg/ha)는 각각 1,961―6,541, 2,161―4,526 및 508― 5,582로 나타났다. 본 연구는 우리나라의 SSH에 대한 취 약성 및 피해 산정에 도움이 되는 기초자료로서 극단기상 과 정상기상 사이의 생산량 차이를 확인하는 데 의의가 있다.
        5,100원
        13.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        양돈산업은 돼지고기 내 웅취발생 예방을 위한 방법으 로 수컷 자돈에게 물리적 거세를 관행적으로 실시해왔다. 그러나 동물복지에 대한 관심이 고조됨에 따라 일부 국가 들에서는 고통 최소화 물리적 거세법 권장 또는 대체 방 법에 대해 연구를 수행하고 있다. 따라서 본 연구에서는 비거세돈(EM; entire male pigs) 및 거세돈(CM; castrated male pigs)에서 이눌린의 급여가 지방조직 내 웅취물질 농도에 미치는 영향을 구명하고자 실시하였다. 시험동물 은 총 26두의 3원 교잡돈(EM, n=18; CM, n=8)을 사용하 였다. 시험 처리구는 3% 이눌린의 급여와 비급여를 설정 하여 총 4개 처리구(EM0, EM3, CM0 및 CM3)로 구성하 였다. 웅취분석을 위해 지방조직은 등지방, 목지방 및 삼 겹지방을 수집하였다. 등지방 내 인돌 농도는 EM0에 비 해 CM3에서 감소하였고(p<0.05) 목지방 및 삼겹지방에서 는 처리구간 차이가 없었다. 지방조직 내 평균 인돌 농도 는 EM0에 비해 EM3, CM0 및 CM3에서 감소하였다 (p<0.05). 등지방 내 스카톨 농도는 CM0, CM3에서 EM0 보다 감소하였다(p<0.05). 또한, 목지방 내 스카톨 농도 및 지방조직 내 평균 스카톨 농도는 CM3에서 EM0과 EM3 보다 감소가 확인되었다(p<0.05). 그러나 안드로스테논 농 도는 분석된 지방조직들 모두에서 처리구간 통계적인 차 이가 없다. 이러한 결과들은 이눌린 급여에 의해 비거세 돈의 지방 내 웅취물질 저감에 부분적인 효과를 나타냈 을 뿐만 아니라 거세돈에서도 웅취물질 감소에 긍정적인 영향을 미쳤음을 시사한다. 따라서, 본 연구결과는 물리적 인 거세가 전면 금지된다면 동물복지형 사양관리 기술개 발의 기초자료로 활용할 수 있을 것이다.
        4,000원
        14.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 소맥 위주 사료에 xylanase 효소제의 첨가가 육성돈의 사양성적, 영양소 소화율, 혈액성상, 분 중 휘발 성 지방산 및 암모니아성 질소 농도에 미치는 영향을 알 아보기 위하여 실시하였다. 총 192두(4처리, 8반복, 반복당 6두)의 육성돈(25.14±0.11 kg)을 공시하여 xylanase 첨가수 준(0, 0.0125, 0.025, 0.0375%)으로 6주간 사양시험을 실시 하였다. xylanase의 첨가수준이 증가함에 따라 전체 사양 구간에서의 일당증체량(ADG), 일일사료섭취량(ADFI) 및 사료요구율(FCR)이 유의적으로 개선되는 효과를 나타냈 다(p<005). 영양소 소화율에 있어서, xylanase 첨가수준이 증가함에 따라 phase Ⅰ에서는 건물 및 에너지, phase Ⅱ 에서는 조단백질 소화율이 유의적으로 개선되었으며, 또 한 육성돈의 혈중 GLU 농도는 사료 내 xylanase의 첨가 수준이 증가함에 따라 유의적으로 증가하는 효과를 보였 다(p<0.05). 반면에, 휘발성 지방산 및 암모니아성 질소 농 도에서 xylanase의 유의적인 첨가효과는 나타나지 않았다 (p>0.05). 결론적으로, 소맥 위주의 사료 내 xylanase의 첨 가는 육성돈의 사양성적, 영양소 소화율 및 혈중 GLU 농 도를 증가시키는데 긍정적인 효과를 보였으며, 육성돈 사 료내 소맥을 주원료로 사용할 경우 xylanse의 적정 첨가 수준은 0.0375%으로 사료된다.
        4,000원
        15.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        돼지의 체세포 핵이식(Somatic cell nuclear transfer,SCNT)은 인간에게 약리적 효과가 있는 단백질, 이종 간 장기이식(xenotransplantation)에 사용되는 장기, 질병 연 구 목적의 모델 동물을 제공한다. 특히 형질전환 돼지를 활용한 심장 이식이 세계 최초로 성공한 후 형질전환 돼 지 생산의 안정화는 다음 연구를 위한 중요한 점으로 대 두되고 있으나, 미니돼지의 체세포 핵이식 배아의 생산 효율은 아직 낮은 실정이다. 형질전환의 성공은 양질의 SCNT 배아 생산에서 시작되어야 한다. 이러한 SCNT 배 아의 생산 효율을 향상할 수 있는 요인 중에는 공여 세포 의 형태가 있으며, 성공적인 공여 세포의 생산을 위해서 는 종축에 따른 세포의 특성을 파악하여야 하고, 혈액형 의 차이에서 발생하는 문제점 해결을 위해 OO 타입의 선 별이 필요하다. 본 연구에서는 지속적인 계대 배양을 통 하여 공여 세포로 사용되는 미니돼지의 태아섬유아세포의 계대 배양 조건을 확립하고자 한다. 또한 미니돼지의 혈 액형을 PCR 기반으로 분석하여 분류하고 OO 타입의 선 별을 통하여 이종 간 이식에 용이하게 공여 세포의 조건 을 확립하였다. 이후 sgRNA(single guide RNA)를 사용하 여 CRISPR-Cpf1로 GGTA1(α-1,3 galactosyl-transferase) 유전자를 knock-out 한 미니돼지의 생산으로, 급성면역반 응을 유발하는 Gal(1,3)Gal epitope이 제거된 미니돼지의 세포 주를 구축 및 체세포 핵이식을 통해 GGTA1 knock-out 미니돼지를 생산하였으며, 이러한 연구는 이후 체세포 핵이식 및 이종 간 장기이식에 중요한 기초자료로 사용될 것이라고 생각된다.
        4,200원
        16.
        2023.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study monitored temperature using electronic sensors and developed a prediction model for compost maturity. The experiment used swine manure in a mechanical composting facility equipped with a screw-type agitator, and the composting process was conducted for 60 d during the summer season in South Korea. Four electronic temperature sensors were installed on the inner wall between the compost piles on Days 7, 14, 21, and 28 for daily temperature monitoring. Compost samples were collected daily for 60 d, and compost maturity was analyzed using the Solvita method. Multiple comparisons, correlations, and modeling were performed using the stat package in R software. The average compost pile temperatures was 39.1±3.9, 36.4±4.3, 31.3±4.5, and 35.4±8.1 on days 7, 14, 21, and 28, respectively, after composting. The average compost maturity according to the composting date was 3.61±0.60, 4.13±0.59, 4.26±0.47, and 4.32 ±0.56 on days 7, 14, 21, and 28, respectively. A significant negative correlation was observed between the compost composting periods (seven, 14, 21, and 28 d) and the temperature of all compost piles (p<0.05), where the correlation coefficients were -0.329, -0.382, -0.507, and -0.634, respectively. A significant positive correlation was observed between the compost composting periods (seven, 14, 21, and 28 d) and the maturity of the compost (p<0.05), where the correlation coefficients were 0.410, 0.550, 0.727, and 0.840, respectively. The model for predicting the maturation of the 14 d average compost pile according to the compost composting period and the average temperature for 14 d was y=0.026 x d – 0.021 x mt.x_14 d (mean temperature for 14 d) + 4.336 (R2=0.7612, p<0.001). This study can be considered a basic reference for predicting compost maturity by the proposed model using electronic temperature sensors.
        4,000원
        17.
        2023.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was designed to evaluate the objective meat qualities of Hanwoo longissimus lumborum muscle after a period of long-term storage (40 days) in which conditions similar to those under which the meat would be stored for export to the Hong Kong beef market were simulated. Twelve LL muscles were sampled from animals slaughtered the previous day at a commercial beef export abattoir and assigned to one of three groups. Each group was subjected to a different packaging condition; Shrink film packed (SFP), vacuum packed (VP), or modified atmosphere packed (MAP)(O2/60%, CO2/40%). Objective meat qualities were assessed at day 1, 7, 21 and 40 of storage. Different Packaging conditions had no noticeable influence on cooking loss significantly. However, the moisture content in both the SFP and MAP groups tended to decline in a linear manner with storage periods throughout the 40 days period. Drip loss of MAP (5.68%) group was much higher in the SFP (3.18%) and VP (2.64%) groups at storage day 40. Redness (CIE a*) of meat color responded in a significant and completely different manner to each packaging method. Redness significantly (p<0.05) and continuously increased 17.51 at day 1 to 20.41 at day 40 in VP group, while MAP linearly dropped and ultimately reached 10.6 after 40 days of aging (p<0.05), at which point the meat had a brown color. Tests of Warner-Bratzler shear force (WBSF) indicated that the tenderness levels of the ready-for-export Hanwoo LL muscles were acceptable 7 days postmortem in the SFP and VP groups, however there was no significant difference between each group. Our gathered data suggests that the packaging method selected for export determines how well the objective qualities of the beef hold up, and indicate that VP is likely the most reliable method.
        4,000원
        18.
        2023.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The long-tailed goral (Naemorhedus caudatus) is classified as 'vulnerable' by the International Union for Conservation of Nature and has been designated an endangered species requiring conservation and management in Korea. The sex determination region of the Y (SRY) gene is a useful marker for the study of paternal lineages; however, the SRY gene of the goral has not yet been sequenced. In this study, the nucleotide sequence of the SRY gene of long-tailed gorals was determined based on the sequence of the SRY gene of goats (Capra hircus). The obtained sequences were aligned with those of other species in the Bovidae family. The long-tailed goral SRY gene comprised 720 base pairs, and its nucleotide and protein sequences were identical to those of goats, sheep (Ovis aries), and cattle (Bos taurus) by 96%, 97%, and 93%, respectively. The results of phylogenetic insights obtained from this study constitute important references for genetic diversity and pedigrees studies of male long-tailed gorals and closely related species.
        4,000원
        19.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study was the acoustic analysis of vocalizations of domestic dogs when they want to play with humans. Using a digital camcorder and microphone, we recorded and acoustically analyzed the vocalizations of six 7-month-old dogs (beagle) when they wanted to play with humans. The vocalizations were classified into five types, namely, barking (type Ⅰ, type Ⅱ), whining (type Ⅰ, type Ⅱ), and howling, based on the shapes of waveforms and spectrograms. There was a significant difference in the fundamental frequency (p<0.01), intensity (p<0.0001), 1st formant (p<0.001), 2nd formant (p<0.0001), 3rd formant (p<0.001), and 4th formant (p<0.05) among the vocalizations, whereas the duration was not different (p<0.05). Whining type I showed high values in the fundamental frequency and 3rd formant, while whining type II showed high values in the fundamental frequency and 1st, 2nd, and 4th formant. Further, bark types I and II showed high intensity values, with bark type II having a high value in the 1st formant. Finally, whining showed high values in the 4th formant only and significantly lower values in the 1st and 2nd formants than other vocalizations. Domestic dogs mainly exhibited barking and whining with differences in characteristics of fundamental frequency, intensity, and formant dispersion when they wanted to play with humans during the experiment. Accordingly, we suggest that vocalization could be a useful method for identifying dogs’ intentions or emotional state in a non-invasive manner.
        4,000원
        20.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The present trial verified the effects of spraying microbial agents on odor reduction in commercial pig farms of different operating sizes and barn types. Farms without microbial agent spraying and those sprayed with microbial agents at two different intervals were compared. The treatments included spraying of water alone every day or a mixture of water plus microbial agent at 24 and 72 h intervals. The experimental farms were divided according to size into 1,000-, 3,000-, and 5,000-head farms and according to barn type into gestation, farrowing, nursery, and grower-finisher farms. To compare odor concentration within each housing barn, ammonia and hydrogen sulfide gas levels were measured. The average concentrations of ammonia (p<0.01) and hydrogen sulfide (p<0.05) gas were the lowest in all types of farms sprayed with the microbial agent at a 24 h interval. In farms sprayed with the microbial agent at a 24 h interval, the decrease in ammonia concentration according to barn type was in the following order: farrowing (p<0.01) (11.0 to 1.8 ppm), nursery (p<0.05) (17.0 to 9.2 ppm), grower-finisher (15.3 to 8.8 ppm), and gestation (9.7 to 6.4 ppm) farms. Moreover, spraying the microbial agent at a 24 h interval significantly (p<0.01) decreased ammonia concentration from 19.9 to 10.4 ppm, from 11.1 to 4.1 ppm, and from 8.8 to 5.1 ppm in 5,000-, 3,000-, and 1,000-head farms, respectively. Overall, spraying microbial agents every day may be the most effective method to reduce odor in commercial pig farms.
        4,000원
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