Cool-season grasses are currently widely used in South Korea, but their productivity and quality may decline due to global warming associated with climate change. Warm-season grasses have shown greater adaptability to heat stress and drought conditions, making them potential alternatives for summer pasture establishment in central and southern Korea. This study aimed to compare the growth characteristics, productivity, and forage value of warm-season grasses bermudagrass and crabgrass for pasture establishment in the central region of South Korea. The experiment was conducted from May 2023 to October 2024 at the National Institute of Animal Science, Cheonan, South Korea. Crabgrass exhibited superior initial establishment and faster growth rates, whereas bermudagrass had poor initial growth, placing it at a competitive disadvantage against weeds. However, after the first cutting, bermudagrass successfully established itself and maintained a stable botanical composition. The annual dry matter productivity of crabgrass (8,586 kg/ha in 2023 and 12,013 kg/ha in 2024) was 32.62% and 40.18% higher, respectively, than that of bermudagrass (5,785 kg/ha in 2023 and 8,570 kg/ha in 2024). In forage value, crabgrass tended to show higher feed value at the initial harvest, while bermudagrass showed higher quality at the later harvests. In conclusion, these results suggest that both crabgrass and bermudagrass have potential for pasture establishment, with carbgrass being more suitable for short-term due to its rapid growth and high productivity, and bermudagrass being more appropriate for long-term due to its stable productivity in regions where overwintering in possible.
A total of 225, 3 weeks old weaned pigs of the Landrace × Yorkshire × Duroc breeds with initial average body weight (BW) of 6.25±0.6 kg were randomly assigned to 3 different treatments based on their BW, with each having 5 replicates. Each replicate contained 15 pigs, resulting in 75 pigs per treatment group. The treatment included a basal diet (CON), CON + allicin and cinnamaldehyde mixture 500 ppm (ALI), CON + Bacillus-based probiotics 500 ppm (PRO) tested for 42 days in a 3-phase feeding program (0–14 as phase 1, days 15–28 as phase 2, and days 29–42 as phase 3). Result shows final BW (6.3%) and average daily gain (9.0%) in the overall phase were higher (p<0.05) in PRO compared with CON. At d 14, the level of Escherichia coli was lower (p<0.05) in ALI (12.0%) and PRO (13.2%) over CON. At days 28 (14.6%) and 42 (12.8%), the level of Escherichia coli was lower (p<0.05) in PRO compared with CON. The level of tumor necrosis factor-α was lower (p<0.05) in PRO over CON (15.0%). Superoxide dismutase (9.2%) and immunoglobulin A (19.4%) were higher (p<0.05) in PRO over CON. We concluded that dietary PRO at 500 ppm showed better performance in piglets by enhancing their growth performance and health.
우리나라의 식량자급률은 49.3% 정도이며, 이중 쌀, 고구 마, 감자 등은 자급률이 높으나 콩, 보리쌀, 옥수수, 밀 등은 자 급률이 낮다. 또한 1인당 연간 쌀 소비량은 갈수록 감소하고 있 고, 과잉 생산에 의해 쌀 가격의 경쟁력 또한 저하되고 있는 실 정이다. 따라서 기존 쌀 중심의 논 이용 작부체계에서 벗어나 다양한 작물을 재배할 수 있는 밭 이용 작부체계로의 전환이 필요하다. 이 시험에서는 남부지역 밭 재배 콩 - 양파 작부체계 에서의 품종 및 파종(정식) 시기에 따른 작부체계 성립 가능성 및 생산성을 구명하고자 하였다. 경남 창녕군 관내 밭 포장에 서 시험을 수행하였으며 작물 별 재배 기간은 양파는 2022년 10월에서 2023년 6월까지, 콩은 2023년 6월부터 2023년 10 월까지였다. 양파는 로망(조생종), 탱크(중생종), 카타마루(중 만생종)의 3종을, 콩은 선유2호(단기성 두부 및 장류용 콩), 대 찬, 태광(이상 일반 두부 및 장류용 콩)의 3종을 시험품종으로 각각 선정하였다. 또한 콩의 파종 시기는 6월 중순(조기), 6월 하순(적기) 및 7월 상순(만기)의 3시기로, 양파의 정식 시기는 10월 하순(조기), 11월 상순(적기), 11월 중순(만기)으로 각각 설정하였다. 주요조사항목은 시험기간 중 기상 상황, 작물 재 배 전·후 토양 화학성, 작물 생육, 수량 특성 및 경제성 등이다. 콩과 양파의 재배기간 중 평균 기온과 강수량은 평년보다 높아 서 고온, 다우의 기상 특성을 보였다. 시험 포장의 토양 화학성 분석 결과, 콩 재배 시 토양 산도 개량, 양이온 무기성분 함량 증 가 및 질소 축적 등의 효과가 있는 것으로 생각된다. 양파에서 는 조생종인 로망의 수확기가 시험 품종 중 가장 빨랐다. 또한 정식기에 따른 양파 수확기는 모든 시험 품종에서 차이가 없었 다. 반면 중생종인 탱크와 중만생종인 카타마루의 상품 수량 및 경제성(소득)은 로망보다 높았다. 정식기에 따른 양파 상품 수량 및 경제성(소득)은 모든 품종에서 차이가 없었다. 콩에서 는 단기성 품종인 선유2호의 수확기가 태광 및 대찬보다 빨랐 다. 선유2호 및 태광에서는 파종기에 따라서 수확기에 차이가 있었으나, 대찬에서는 모든 파종기에서 수확기가 동일했다. 상품수량 및 경제성(소득)은 대찬이 태광, 선유2호보다 높았 다. 작물 별 파종(정식)기, 수확기에 따른 후작물 재배 포장 준 비 기간과 경제성(소득) 등을 고려했을 때, 콩(품종 : 대찬, 파 종기 : 6월 하순) - 양파(품종 : 탱크, 정식기 : 11월 상순)의 작 부 체계가 본 시험에서는 가장 적절한 것으로 판단된다.
This study was conducted to investigate changes in the productivity of Italian ryegrass seeds according to the timing of harvest after heading in the southern region. The Italian ryegrass variety ‘Greencall’ was sown in Jinju, Gyeongsangnam-do, in the fall of 2022. Four harvest timings were tested (30, 40, 50, and 60 days after heading), with a randomized complete block design and three replicates. Sowing in the test plots took place on October 10, 2022, and harvesting was carried out from 30 days after heading on May 18 to 60 days. The plant height was the longest (99.1 cm) in the plot harvested 30 days after heading and decreased as the harvest was delayed. No significant differences were observed among treatments in terms of lodging resistance, disease resistance, and cold resistance. However, lodging severity increased over time after heading (7∼9). Disease incidence was also higher in plots harvested 50 and 60 days after heading. The length of the spike was shortest (38.76 cm) in the plot harvested 50 days after heading, and the number of seeds per spike was the lowest (42 seeds/spike) in the plot harvested 60 days after heading. The dry matter content of seeds increased with the delay in harvest, while dry matter yield decreased, with the lowest yield observed in the plot harvested 40 days after heading (3,031 kg/ha, p<0.05). The dry matter content of seed straw was highest at 75.73% in the plot harvested 50 days after heading and dropped to 34.99% 60 days after heading due to rainfall. The dry matter productivity of the seed straw was the lowest in the plot harvested 40 days after heading. The feed value of the seed straw also decreased with delayed harvest, with an average RFV (Relative Feed Value) of 91. In conclusion, the optimal harvest timing for fall-sown Italian ryegrass intended for seed production in the southern region appears to be 30 days after heading.
In order to develop a stable production and delicious unique cultivar of beech mushrooms, we generated hybrids using wild resources collected domestically, and we developed excellent strains by identifying the mycelial cultivability of the hybrid strains. The developed strains were cultivated according to the type of spawn and incubation time, and strains with excellent yield and shape were first selected, and second strains with less bitterness and excellent taste were selected through quantitative descriptive analysis. This was verified in farms, and ‘HM6-6’, which had a good reputation in the field, was directly developed cultivars as ‘Maruking’. In addition, the yield was high overall in the 90-day culture of the growth substrate inoculated with solid spawn, and the ‘Maruking’ cultivar, was also best in the 90-day culture. The yield was high overall in the 75-day culture of the liquid spawn, but ‘Maruking’ showed excellent yield when cultured for 70 days.
This study aims to examine total factor productivity (TFP) and its determinants in offshore fisheries under the worsening fishing environment and to propose policy improvement based on the estimation results. We identified a decline in TFP of offshore fisheries from 2012 to 2020 employing the global Malmquist productivity index (GMPI), with the primary cause being the regression of the production possibility frontier due to the reduction of fishery resources. Moreover, utilizing the system generalized method of moments (GMM), we found that the determinants, such as the cessation of operations in Japan’s EEZ, vessel age, fishing experience, and oil prices, contribute to a decrease in the TFP of offshore fisheries. Therefore, this study suggests implementing a total allowable catch (TAC)-centered fishery resource management policy, along with reducing loan interest rates and extending the repayment period for the vessel modernization project. Furthermore, it is necessary to improve the TFP of offshore fisheries by providing regular training for fishermen, implementing the tax-free petroleum stockpiling project, and developing alternative fishing grounds.
Cherry tomato (Solanum lycopersicum L,. var. cerasiforme Mill.) is small fruits with a bright red color resembling a cherry and having an excellent taste, sweet and juicy ambience. So far, no cherry tomato variety was registered in Ethiopia. Consequently, six genotypes were imported from National Institute of Horticulture and Herbal Sciences (NIHHS), Rural Development Administration (RDA) Republic of Korea, and field experiment was conducted in RCBD with three replications at six Ethiopian testing sites, with irrigation, during off-seasons of 2021 and 2022 to identify high yielding, well adapted and good quality varieties. The overall analysis of variance across locations and years showed non-significant difference among the genotypes for marketable and total yields. But separate analysis for each site has revealed significant differences among genotypes at Melkassa, Koka, Adami- Tulu and Fogera, unlike that of Kulumsa and Woramit. There were significant differences (P < 0.05) among these genotypes for fruit numbers per plant, average fruit weight, fruits per cluster, plant height, skin thickness, juice volume and total soluble solid. Wonhong No.3 gave higher marketable (24.49 t/ha) and total (26.19 t/ha) yields, and generally Wonhong Nos.3 and 5 had higher yields and good qualities across these tested locations and years. Hence, Wonhong No.3 (designated as Jorgie-1) was registered for its higher yield, non-cracking, good TSS and color, while Wonhong No.5 (renamed as Jorgie-2) was preferred for its smaller fruit size, reasonable yield and quality (TSS, color, non-cracking). Hence, both varieties were officially registered in 2023 season for commercial production in different agro-ecologies of Ethiopia, and they are believed to add more economic and nutritional values for the tomato producers and the consumers. They can also support the intensification of tomato cultivation in peri-urban and urban agriculture, where demands and thus government focus are increasingly growing.
This study was conducted to analyze the productivity and economic feasibility of truss-limited tomatoes (Lycopersicon esculentum L.) grown at a high density in Cambodia during the rainy season. During the rainy season in Cambodia, due to excessive rain and very high temperature, tomatoes cannot grow well in an open field, leading to a greatly reduced yield. High density truss-limited cultivation (HDTLC) of tomatoes can shorten the growing season and increase yields. In conventional cultivation (control), tomatoes were transplanted at a spacing of 70×40 cm and harvested up to the 4th fruit cluster. In HDTLC, tomatoes were transplanted at a spacing of 20×20 cm or 25×25 cm and harvested up to the 2nd fruit cluster. Plant heights in HDTLC were higher than those in the control at 22 days after transplanting (DAT). At 39 DAT, plant heights did not differ between 25×25 cm and control. At 60 DAT, plant height, stem diameter, leaf length, and leaf width of the HDTLC were lower than those of the control. Fruit length and width were also lower in HDTLC compared to those of the control. However, sugar content was more than 19% higher in HDTLC compared to that in the control. Yield per plant of the control was the highest, but yields per ha in HDTLCs were 99% (20×20 cm) and 38% (25×25 cm) higher, respectively, compared to that of the control. No pesticides were used for disease control in this experiment. However, to ensure yield, it is recommended to observe the disease status of plants and spray pesticides at the appropriate time. The disease index (1: disease-free; 5: all leaves were disease-infected) of late blight (Phytophthora indestans) was significantly higher for 20×20 cm (4.5) and 25×25 cm (3.6) groups compared to the control (2.0). Income with 20×20 cm (5,668 thousand KRW) and 25×25 cm (1,863 thousand KRW) were 4.9 and 1.6 times higher, respectively, compared to that with the control (1,149 thousand KRW). So, we want to spread the HDTLC technology, which transplanting of tomato seedlings at 20×20 cm intervals and harvests up to 2nd fruit cluster, to Cambodian farmers.
본 시험은 마늘 절임에서 분리 동정된 Leuconostoc citreum SK2556 균주에 의한 마늘 발효 배양액 급여가 산란계의 계란 생산성, 계란 품질, 혈액 성상에 미치는 영향을 알아보고자 실시하였다. 시험 동물은 33주령 산란계(Hy-Line Brown) 180수를 공시하였고, 5주간 사양시험을 실시하였 다. 전체 사양기간동안 산란율은 대조구, FG (발효마늘) 0.3 및 FG 0.5 처리구는 78.02~78.53의 범위로 유의적인 차이가 없었으나, FG 0.1 처리구(75.37±3.22)는 다른 처리구들에 비교하여 감소하였다(P<0.05). 사료섭취량과 사료요구율에서는 유의한 차이가 관찰되지 않았다. 시험 전기간 Haugh unit에서는 마늘 발효액 FG 0.1이 대조구와 FG 0.5에 비해 유의하게 증가하였다(P<0.05). 혈액 내 Glucose는 모든 마늘 발효액 처리구가 대조구보다 유의하게 낮았다(P<0.01). 간 기능의 이상 여부를 나타내는 알칼리인산분해효소(alkaline phosphatase; ALP)는 FG 0.3 처리구가 대조구보다 유의하게 감소하였다(P<0.05). 본 연구 결과, 산란계 사료 내 마늘 발효 배양액 급여는 계란의 Haugh unit의 향상으로 계란의 신선도를 개선시켰을 뿐만 아니라, 건강 유지에 긍정적인 영향을 미쳐 사료첨가제로서의 이용가능성을 제시하고자 한다.
본 연구는 로즈마리 다단재배 시 층별 환경조건 및 하위선반 보조 광원이 어린순 품질과 생산성에 미치는 영향을 구명하고 자 수행되었다. 정아를 제거한 커먼 로즈마리의 중간부 삽수 10cm를 128공 트레이에 삽목하여 발근시킨 뒤 750, 1,300, 2,000mL의 화분에 이식하였다. 이후 2연동 온실 내 다단선반 (3단)에 배치하여 저면관수 방식으로 재배하였다. 다단선반 층별 어린순 생산성은 3층(최상층)에서 가장 우수하였으나, 여름철 광 과다에 의한 줄기 목질화로 9월 이후 생산성이 급감 하였다. 반면 하위 2개 층은 재배 후기까지 어린순의 생장속도 가 빨랐으나, 줄기 연화 및 엽 상편생장으로 품질이 감소하였 다. 다단선반 3층 여름철 광 과다 문제 해결을 위해 7, 8월 30% 차광 재배시 무차광 대비 단위 면적당 어린순 수확 줄기수 210%, 생체중 162% 증수하였다. 하위층 광 부족 문제를 개선 하고자 보조 광원 설치 재배 시 LED 30W에서 6-9월 어린순 수확량이 보조광원 미설치 대비 168% 증가하였으나, 9월 이 후 오히려 생산성을 감소시켰다. 따라서 로즈마리 다단재배 시 3층(최상층)은 7-8월 30% 차광으로 줄기 목질화를 막고, 하 위층은 6-9월 LED 30W로 일시적 보광을 통해 어린순 생육 을 증대시킨다면 어린순 집약생산이 가능할 것으로 판단된다.
본 연구는 로즈마리 다단재배 시 근권부 용적이 어린순 생산성에 미치는 영향을 구명하고자 수행되었다. 정아를 제거한 커먼 로즈마리의 중간부 삽수 10cm를 128공 트레이에 삽목 하여 발근시킨 뒤 125, 200, 550, 750, 1,300 및 2,000mL의 용 기에 이식하여 1, 2년생 삽목묘 어린순의 생육특성과 수량성 을 비교하였다. 1년생 로즈마리의 경우 초기 생육(이식 후 30 일)은 용기 550mL 이상에서 처리 간 뚜렷한 차이가 없었으나, 2년생 로즈마리의 경우 용기가 클수록 생육이 비례하는 경향 을 보였다. 1, 2년생 로즈마리의 지하부 생체중은 용기 550mL 에서 7월 25일 조사 시 각각 6.9g, 24.4g, 11월 24일 조사 시 각 각 10.3g, 24.9g으로 가장 낮았고, 용기 750-2,000mL에서 는 처리 간 차이가 보이지 않았다. 반면 지상부 생체중은 1년 생 로즈마리의 경우 용기가 클수록 증가하다가 1,300mL 이 상에서는 통계적 차이가 없었으며, 2년생 로즈마리 역시 용기 가 클수록 생체중이 유의하게 높았다. 어린순 품질은 1년생 로 즈마리의 경우 용기 2,000mL에서 가장 우수하였으나, 2년생 로즈마리의 경우 시기별 품질 차이를 보였다. 단위 화분당 어 린순 생산성은 1,300mL에서 가장 높았으나, 단위 면적당으 로 환산할 경우 750mL에서 가장 우수하게 관찰되었다. 따라 서 로즈마리 어린순 다단재배를 통한 집약생산에 가장 적합한 용기 크기는 750mL로 판단된다.
The objective of this study was to compare the feeding effects of imported timothy hay, domestic Italian ryegrass silage (IRGS) and IRG dried by hot-air dry system (IRGHDS) under basic total mixed ration (bTMR) on rumination activity, milk production, and milk composition in lactating dairy cows. Eighteen Holstein dairy cows were divided into three groups: control (bTMR + imported timothy hay), treatment 1 (bTMR + IRGS) and treatment 2 (TMR + IRGHDS) groups. The study was conducted over a total period of 24 days, including a 10 days adaptation period and a 14 days main experimental period. The results indicate body weight was not significantly different between the three groups (p>0.05), and rumination time was significantly higher in the treatment 1 group compared with the control group (p<0.001). Milk fat, protein, and lactose were not significantly different between the three groups (p>0.05), however, somatic cell counts were significantly lower in the treatment 1 group compared with the control group (p<0.001). As a result of the economic feasibility analysis, it is expected that feeding TMR using IRGS and IRGHDS will increase profit by 402.8 won/day and 331.4 won/day per cow compared to imported timothy hay. Therefore, IRGS and IRGHDS can be used as substitutes for imported timothy hay in feeding lactating dairy cows.
We compared the reproductive performance, non-productive performance, and milk composition performance of two groups of lactating cows that were either rice straw or tall fescue. We also compared and analyzed these parameters after the first parturition during the breeding period. The calving interval, artificial insemination, and duration from calving to conception were longer in the rice straw group than in the tall fescue group. The 305-day and peak milk yields were significantly higher in the tall fescue group than in the rice straw group (p<0.01). Milk fat content was significantly higher in the tall fescue group than in the rice straw group (p<0.001), but milk protein content was the same between the feeding groups. The difference in raw milk sales income between rice straw and tall fescue groups tended to increase as the number of lactations increased, but there was no effect of reduced feed costs. Analysis of the milk production and raw milk sales income of the surveyed farms revealed that the average milk production per head was significantly (p<0.05) higher in the tall fescue group than in the rice straw group, and raw milk sales income showed a similar tendency. Overall, these results provide important details to be considered when selecting feed as a way to reduce milk production and heifer raising costs. However, there remains a need for future follow-up studies exploring the relationship between feed choice and the management of heifers.
The experiment was conducted to determine the changes in seed productivity of Italian ryegrass (Lolium multiflorum Lam.) according to nitrogen fertilization levels in the southern region of Korea. Italian ryegrass (IRG) variety 'Green Call' was sown in the fall of 2021 in Jinju, Gyeongsangnam-do. The experiment consisted of three nitrogen fertilizer levels (100, 120, and 140 N kg/ha) with three replications using a randomized complete block design. Harvesting was done approximately 30 days after heading on May 18th. There was no difference in heading date among treatments, which occurred on April 18th. The longest IRG was observed in the 140 N kg/ha treatment, but there was no significant difference. No significant differences were observed in lodging, disease resistance, and cold tolerance among treatments, but lodging was severe in all treatments. The length of the spike averaged 44.95 cm, with no difference among treatments, and the number of seeds per spike was highest in the 120 N kg/ha treatment. Seed yield increased with increasing nitrogen fertilizer levels, averaging 3,707 kg/ha (as-fed basis). DM content of seed and straw averaged 76.95% and 62.19%, respectively, with no significant differences among treatments. The remaining straw after harvesting averaged 6,525 kg/ha on a dry matter basis, with the highest value observed in the 140 N kg/ha treatment. Overall, considering the results, the optimal nitrogen fertilizer application rate for seed production of Italian ryegrass in the southern region when sown in autumn was found to be 120 N kg/ha.
This study was carried out to investigate the growth characteristics, yield and chemical compositions of whole crop barley (Hordeum vulgare L.) according to mixing ratio of chemical fertilizer (CF) and liquid swine manure (LSM) in the paddy field cultivation. The experimental design was arranged in a randomized block design with five treatments and three replications. The manure fertilizer ratio of five treatments were CF 100% (T1), CF 70% + LSM 30% (T2), CF 50% + LSM 50% (T3), CF 30% + LSM 70% (T4), and LSM 100% (T5) of whole crop barley. At this time, the application of liquid swine manure was based solely on the nitrogen. Plant length was higher at T1 as compared to other treatments (T2, T3, T4 and T5). Fresh yield, dry matter yield and total digestive nutrients (TDN) yield were the highest in T1, whereas the lowest in T5 treatment (p<0.05). Chemical compositions (crude protein, crude fat, neutral detergent fiber, acid detergent fiber and TDN) did not show significant difference among treatments. Ca and Na contents were significantly lower at T1 as compared to other treatments (T2, T3, T4 and T5). However, Mg and P contents were significantly higher at T1 as compared to other treatments(p<0.05). There was no significant difference in total free sugar content among T2, T3, T4 and T5 treatments, but the chemical fertilizer (T1) was significantly lower than the other treatments (p<0.01). Considering the above results, liquid swine manure application showed lower dry matter yield and TDN yield than chemical fertilizer, but higher free sugar content. Therefore, in order to increase the productivity of whole crop barley, it is considered desirable to mix liquid fertilizer with chemical fertilizer, taking into account the decomposition rate and insufficient components (P, K) of the liquid swine manure.
This study was conducted to determine the optimal irrigation starting point by analyzing tree growth, physiological responses, fruit quality, and productivity in peach orchards. Seven-year-old ‘Kawanakajima Hakuto’ peach trees were used in an experimental field (35°49′30.4″N, 127°01′33.2″E) located within the National Institute of Horticultural and Herbal Science located in Wanju-gun, Jeollabuk-do. The irrigation starting point was set with four levels of –20, –40, –60, and –80 kPa from June to September 2022. While there were no significant differences in increase of trunk cross-section area and leaf area among treatments, shoot length and diameter decreased in the –80 kPa and –20 kPa treatments. The photosynthetic rate measured in August was highest for –60 kPa (17.7 μmol·m-2·s-1), followed by –40 kPa (15.6 μmol·m-2·s-1), –20 kPa (14.5 μmol·m-2·s-1) and –80 kPa (14.0 μmol·m-2·s-1). SPAD value measured in May and August was lower in the –80 kPa and –20 kPa treatments than in the –60 kPa and –40 kPa treatments. The harvest date reached three days earlier in the –20 kPa treatment compared to other treatments. The fruit weight was highest in the –60 kPa (379.1 g), followed by –40 kPa (344.0 g), –80 kPa (321.0 g) and –20 kPa (274.9 g). Firmness was the lowest in the –20 kPa treatment. The soluble solid content was highest in the –60 kPa treatment (13.3°Bx).The ratio of marketable fruits was highest in the –60 kPa treatment (50.7%) and lowest in the –80 kPa treatment (23.4%). In conclusion, we suggest that setting the irrigation starting point at –60 kPa could improve the fruit quality and yield in peach orchards.
본 연구는 사료내 비테인, 글라이신, 그리고 콜린의 혼합 첨가가 고온 스트레스 환경에서 노령 산란계의 생산성, 난품질, 면역 반응 및 혈액성상에 미치는 영향을 조사하고자 수행되었다. 총 336마리의 86주령 로만 갈색종 노령 산란계를 6처리 7반복, 반복당 8수씩 임의 배치하였다. 대조구는 모든 영양소 및 에너지 요구량을 충족하거나 초과하도록 배합하였다. 대조구를 제외한 사료 처리구는 0.2% 비테인, 0.62% 글라이신, 그리고 0.32% 콜린을 단독, 두 가지 혼합, 혹은 세 가지 혼합으로 사료내 첨가하였다. 실험은 8주 동안 진행되었으며, 모든 산란계는 매일 8시간 동안 평균 온도 31.7±1.7℃, 습도 57%의 고온 스트레스 조건에서 사양되었고, 이외 시간에는 평균 온도 27±1.3℃, 습도 57%에서 사양하였다. 실험 결과, 비테인, 글라이신 및 콜린의 첨가는 생산성, 난품질, 그리고 면역 반응에 유의적인 영향을 미치지 않았다. 그러나, 0.2% 비테인과 0.62% 글라이신을 혼합 첨가한 처리구에서 혈청 알라닌 아미노전이효소 농도가 유의적으로 감소했다. 하지만, 다른 혈청 지표들은 처리간 유의적인 차이가 관찰되지 않았다. 결론적으로, 현재 수준에서 사료내 비테인, 글라이신, 그리고 콜린의 혼합 첨가는 고온 스트레스 환경에서 사양되는 노령 산란계의 생산성, 난품질, 면역 반응 및 혈액 성상에 긍정적인 영향을 미치지 않는다고 판단된다.
본 연구는 고온 환경에서 사료내 트립토판과 나이아신의 첨가가 산란계의 생산성, 난품질, 지방간 지표 및 혈액성상에 미치는 상호작용 효과를 조사하고자 수행되었다. 총 384수의 25주령 로만 갈색종 산란계를 4처리 8반복으로 반복당 12수씩 무작위 임의 배치하였다. 기본 사료는 트립토판과 나이아신의 추가적인 첨가는 없으며 모든 영양소 및 에너지는 로만갈색종 산란계의 요구량에 충족하거나 초과하도록 배합되었다. 사료 처리구는 2 × 2 요인 실험 설계법으로 두 가지 수준의 트립토판(0 및 0.16%)과 두 가지 수준의 나이아신(0 및 0.03%)이 포함되었다. 모든 산란계의 사양환경은 일반 농가에서 낮시간에 온도가 올라가는 점을 고려하여 일일 중 8시간은 온도 31.4 ± 1.17℃, 습도 86.0 ± 4.28%으로 설정하였으며, 나머지 16시간은 온도 26.7 ± 1.10℃, 습도 61.7 ± 6.34%로 유지하여 주기적인 고온 환경을 조성하였다. 실험은 10주간 진행되었다. 실험 결과 사료내 트립토판과 나이아신의 주요 효과와 상호작용은 나타나지 않았다. 이와 유사하게, 난각 강도, 난각 두께, 난각색, 난황색 및 호우유닛에 대한 상호작용 도 나타나지 않았다. 주요 효과로 0.03%의 나이아신 첨가는 난황색을 유의적으로 감소시켰으나 호우유닛은 유의적으로 증가시켰다. 하지만, 0.16%의 트립토판 첨가는 난품질에 영향을 끼치지 않았다. 지방간 지표와 혈액성상에서 사료내 트립토판과 나이아신의 주요 효과 및 상호작용은 나타나지 않았다. 결론적으로, 본 연구에서 설정한 농도의 사료내 트립토판과 나이아신의 첨가는 고온 환경에서 사양되는 산란계의 생산성, 난품질, 지방간 지표 및 혈액성상에 긍정적인 영향을 미치지 않았다.