• 한국수산과학회지
• /
• 제54권4호
• /
• pp.434-444
• /
• 2021

The decrease in fatness of the Pacific oyster Crassostrea gigas, which consequently results in decrease in the profit of aquaculture industry, has become a source of serious concern in southeast coast of Korea. The ratio of flesh (edible portion) to total oyster weight, commonly called edible portion yield ("suyul" in Korean), have been used as a fatness index for the healthy and valuable state of oyster from the early stage of oyster farming in Korea. More than 360 data sets were collected from early culturing periods (in the 1970s) to the present from approximately 15 published literatures to evaluate the long-term fatness trend of oyster, reared particularly in submerged longline culturing system in Gyeongsangnam-do province. Slight decrease in oyster fatness during the 1970s to 1990s was detected in Tongyeong and Geoje Bays; however, from the 1990s to the present, clear decreasing trends were observed with a decrease of 0.04-0.08% year^-1, especially during harvest season. Oyster mass production per unit area almost doubled within a short period in the early 2000s; however, changes in coastal environment factors inhibited the fattening of shellfish from the mid 1990s. These results indicate that the severe competition in feeding and low biological production in water column might be some convincing reasons for the decrease in fatness of oyster from the 1990s, in Tongyeong and Geoje Bays, Korea.

• 농업과학연구
• /
• 제48권3호
• /
• pp.387-396
• /
• 2021

This study was conducted to provide basic data for efficient Hanwoo beef production by conducting a comparison of growth performance, blood metabolites, testosterone, and carcass characteristics of Hanwoo according to complete and hemi-castration. Twelve Hanwoo calves were allotted to two treatment groups as follows: CC = complete-castration and HC = hemi-castration method of removing only one testicle. At the end of the test, the body weight was 66 kg higher in HC than in CC, and the average daily gain increased by 12.6% (p < 0.05). The feed conversion ratio was significantly improved in HC compared to CC (p < 0.05). Serum cholesterol and triglyceride concentrations were significantly higher in CC than HC in both the growing and fattening periods (p < 0.05), and serum testosterone concentrations before castration were similar between HC and CC, but steadily increasing in HC after castration. Back fat thickness and marbling score were significantly higher in CC than HC in the entire period (p < 0.01). In the results of this study, hemi-castration can improve body weight gain and feed conversion ratio due to the influence of male hormones compared to complete castration, but it is considered that there will be difficulties in producing high-quality meat with a high marbling score.

• Animal Bioscience
• /
• 제34권5호
• /
• pp.914-921
• /
• 2021

Objective: The objective of this study was to compare growth performance, carcass traits and meat quality in young bulls, steers and heifers produced by crossing Limousin bulls with Holstein-Friesian cows, fattened semi-intensively and slaughtered at 18 months of age. Methods: Thirty-one young calves were reared in a conventional production system, and were fed milk replacer, hay and concentrate. At 6 months of age, the animals were divided into groups based on gender, and were fed a total mixed ration composed of grass silage, concentrates I and II in a semi-intensive production system. At the end of the fattening period (18 months), the animals were slaughtered, carcass quality was evaluated, and samples of musculus longissimus thoracis were collected to determine the proximate composition and quality of meat. Results: Bulls were characterized by the highest percentage share of the most valuable cuts in the carcass, and three-rib sections from bull carcasses had the highest lean meat content with low intramuscular fat content (0.93%). No significant differences in carcass conformation, dressing percentage or the percentage share of round in the right half-carcass were found between bulls vs. steers and heifers. Heifers and steers had higher carcass fat content than bulls, which had a positive influence on the sensory properties of beef. In comparison with the meat of bulls, the meat of steers and heifers was characterized by more desirable physical properties and sensory attributes (water-holding capacity, shear force, color lightness, aroma, juiciness, tenderness, flavor). Conclusion: Under the semi-intensive production system, heifers and steers had higher carcass fat content than bulls, which had a positive effect on the sensory properties of beef. Bulls are better suited for intensive systems, which contribute to improving the quality of their meat. The results of this study may encourage producers to breed steers and heifers for beef.

• 한국농공학회논문집
• /
• 제63권4호
• /
• pp.33-41
• /
• 2021

The emission characteristics and emission factors were determined by measuring the concentration of methane (CH₄) and nitrous oxide (N₂O), the amount of ventilation, etc. in the two fattening rooms which have the same environment in winter. As a result of monitoring, the average concentration of CH₄ and N₂O was 20.7-26.7 ppm and 1.4-1.6 ppm. The average temperature inside the room was measured at 20.0-21.4℃, and the average ventilation was 1345.4-1567.3 m³/h. The daily emission of CH₄ for the first 30 days showed a constant emission of 3.6-8.2 g/d/m²/pig, but thereafter, the emission increased rapidly. The daily emission of N₂O was 0.7-1.3 g/d/m²/pig, showing stable emission during the test period, and relatively insignificant emission compared to the emission of CH₄. After repeated test, it was confirmed that there was no significant difference between the two rooms. As a result, the CH₄ 6. 21 g/d/m²/pig and N₂O 1.02 g/d/m²/pig average emission for each room was derived.

• Animal Bioscience
• /
• 제34권3_spc호
• /
• pp.363-370
• /
• 2021

Objective: The effect of garlic powder (GP) and phenyl acetic (PA) acid throughout the fattening period of broiler chickens on performance, blood parameters, immune, and antioxidant parameters as well as carcass traits was evaluated. Methods: A total of 210 day-old Cobb broiler chicks were randomly distributed into seven dietary treatments having five replications with six chicks per replicate. The first group (control) fed a basal diet without supplements, whereas the 2nd, 3rd, and 4th group were fed basal diet plus 0.25, 0.50, and 0.75 g GP/kg diet, respectively and the group 5th, 6th, and 7th were fed on the basal diet plus 0.25, 0.50, and 0.75 g PA/kg diet. Results: Broiler body weight and gain at 21 and 42 days were increased (p<0.05) with diets supplemented with GP and PA. Red blood cells and hemoglobin were improved in chickens fed diets enriched with GP. Broiler chickens received diets containing either GP or PA recorded the higher values (p<0.05) of total protein, globulin, high-density lipoprotein, immunoglobulin M (IgM), and IgG, superoxide dismutase and total antioxidant capacity; while, blood total cholesterol, low-density lipoprotein, aspartate-aminotransferase, and malondialdehyde were lowered (p<0.05) compared to control-diet. Liver and immune-related organs weight were improved (p<0.05) in broilers fed diet supplemented with GP and PA. Conclusion: Feeding of GP or PA in diet had positive effects on performance traits and immunological, antioxidant and physiological status of broilers. Thus, the use of tested feed additives as an eco-friendly alternative to antibiotics produced a positive effect on animal health.

• 한국축산식품학회지
• /
• 제41권1호
• /
• pp.45-58
• /
• 2021

This study investigated the dietary effect of total mixed ration (TMR) based on high roughage content on the growth performance, carcass characteristics, and meat quality of Hanwoo steers. Twenty-four Hanwoo steers (average body weight, 195.3±4.7 kg; age, 8.5 mon) were randomly allocated to three experimental groups according to forage and concentrate ratio (DM basis): 25:75 (control), 50:50 (T50), and 70:30 (T70). Productivity in the fattening period and final body weight were significantly higher in the control. Average daily gain and feed conversion ratio were the same among treatments. Serum parameters, cholesterol, blood urea nitrogen, and total protein were higher in the control. Carcass weight was comparable in the control and T50 but feeding more roughage was significantly correlated with a higher intramuscular fat. Shear strength and drip loss were higher while n-6/n-3 was lower in T70 compared to the other groups. However, meat color was not significantly different among treatments. In terms of free amino acid contents, glutamic acid and glycine were higher in the control than T50 and T70. Overall, feeding Hanwoo steers with high forage content TMR had the lowest n-6/n-3 ratio of fatty acid content but highest intramuscular fat, shear strength, and drip loss. High forage content TMR is the best feed for Hanwoo steers that gives more benefits for human health and consumption but also provides the best meat grade and quality, which is important in the beef market in Korea.

• 한국초지조사료학회지
• /
• 제30권3호
• /
• pp.257-266
• /
• 2010

본 연구는 답리작에서 보리를 재배하여 사일리지를 조제하고 거세 한우에게 청보리 사일리지를 급여하여 성장, 사료이용성, 도체특성 및 육질개선 효과를 구명하고자 전북 정읍 농가에서 4개월령 거세 한우 육성우 21두를 공시하여 27개령까지 사육하였다. 대조구(일반볏짚구), 청보리 사일리지구, 생볏짚 사일리지+청보리 사일리지구 등 3처리를 두었으며, 배합사료는 육성기는 체중의 1.5%, 비육전기는 1.8%, 비육후기는 자유 채식하도록 하였고, 조사료는 사육기간 자유채식을 원칙으로 하였다. 청보리 사일리지의 평균 생산량은 ha당 사일리지 17,135 kg, 건물 6,011 kg 이었으며, 사일리지의 품질등급은 청보리에서 2~3등급, 생볏짚은 4등급이었다. 청보리 사일리지 급여로 거세 한우증체와 배합사료 절감효과가 뚜렷하였는데, 육성기에는 일당증체 65% 증가, kg 증체당 배합사료 35% 절감, 비육전기는 일당증체 7% 증가, kg 증체당 배합사료 19% 절감, 그리고 전기간으로는 일당증체 8% 증가, kg 증체당 배합사료 18% 절감효과가 있었다. 또 청보리 사일리지구에서 육질 1등급 이상 출현율은 62.5%로 대조구(37.5%)에 비해 높았으며, 근내지방도도 4.38로 대조구(2.75)에 비해 높았고, 고기의 보수력, 가열감량, 다즙성, 연도, 향미 등도 우수하였다(p<0.05). 답리작 재배 청보리는 양질 사료작물로 거세 한우의 증체와 배합사료 절감, 육질개선에 효과적이었으며, 육성기와 비육전기 위주 급여가 바람직하였고, 답리작을 이용한 월동 사료작물 재배확대가 기대되었다.

• 한국초지조사료학회지
• /
• 제37권2호
• /
• pp.176-182
• /
• 2017

본 연구는 단백질 균형시험에 의한 흑염소의 1일 유지 단백질 요구량을 구하기 위해 수행되었다. 평균체중 $31.78{\pm}4.54$의 8개월 령의 비육기 수컷 흑염소 6두를 공시하였고, $3{\times}3$ Latin square design 방법으로 처리구별 사료 내 조단백질 수준을 달리하여 흑염소에 미치는 영향을 조사하였다. 시험 기간은 2014년 10월 12일부터 2014년 11월 21일까지 40일간 이천의 흑염소 농장에서 진행하였다. 사료의 조단백질 수준은 처리구별로 13%(T1), 16%(T2), 19%(T3) 이며 TDN은 66%로 하여 배합한 TMR 사료를 사용하였으며 1일 사료급여량은 체중의 1.5%를 오후 5시경에 급여하였다. 처리구별 건물섭취량은 T1구가 925.14g/d, T2구가 966.67g/d, T3구가 936.08g/d으로 T2구에서 가장 높았고, 일당증체량은 T2구가 167.13g/d으로 T1과 T3구의 각각 109.26g/d, 118.98g/d 보다 높게 나타났으나 유의적 차이는 보이지 않았다. 건물 소화율은 T1과 T2과 T3구 각각 73.68%, 71.81%, 73.77%로 처리구간에 따른 차이는 나타나지 않았다. 조단백질 소화율은 T3구가 82.42%로 T1과 T2구 각각 72.73%, 65.72% 보다 유의하게 높았다(p<0.05). 조지방 소화율은 처리구별 유의성은 인정되지 않았다. ADF 소화율은 69.13%로 T1구에서 가장 높았다(p<0.05). CF와 NDF 소화율은 46.88~59.76%, 63.29~73.73%의 범위로 처리구간 유의성은 인정되지 않았다. 조단백질 섭취량은 T1과 T2과 T3구에서 각각 128.78g/d, 154.57g/d, 181.23g/d로 사료 내 단백질 수준이 높아질수록 유의적으로 증가하였다(p<0.05). 대사 체중 당 CP 섭취량과 CP 축적량과의 관계식에서 CP 균형이 0이 되는 X축 절편은 $1.63g/BW^{0.75}$이었다. 본 연구결과 8개월 령 수컷 흑염소에게 필요한 유지 조단백질 요구량은 $1.63g/BW^{0.75}$이며 흑염소의 사양표준 설정에 기초자료가 될 것으로 사료된다. 그러나 유지 단백질 요구량에는 성장단계 및 사양방법, 성별에 따라 차이가 발생할 수 있기 때문에 향후 그러한 요인들을 기준으로 한 흑염소 단백질 연구가 단계적으로 필요할 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권5호
• /
• pp.770-777
• /
• 2020

Objective: This study was conducted to determine early hereditary endowment to establish a short-term feeding program. Methods: Hanwoo steers (n = 140) were equally distributed into four groups (35/group) based on genetic meat yield index (MYI) viz. the greatest, great, low, and the lowest at Jukam Hanwoo farm, Goheung. All animals were fed in group pens (5 animals/pen) with similar feed depending on the growth stage. Rice straw was provided ad libitum, whereas concentrate was fed at 5.71 kg during the growing period (6 to 13 mo) and 9.4 kg during the fattening period (13 to 28 mo). Body weight (BW) was measured at two-month intervals, whereas carcass weight was determined at slaughtering at about 31 months of age. The Affymetrix Bovine Axiom Array 640K single nucleotide polymorphism (SNP) chip was used to determine the meat quantity-related gene in the blood. Results: After 6 months, the highest (p<0.05) BW was observed in the greatest MYI group (190.77 kg) and the lowest (p<0.05) in the lowest MYI group (173.51 kg). The great MYI group also showed significantly (p<0.05) higher BW than the lowest MYI group. After 16 and 24 months, the greatest MYI group had the highest BW gain (p<0.05) and were therefore slaughtered the earliest. Carcass weight was significantly (p<0.05) higher in the greatest and the great MYI groups followed by the low and the lowest MYI groups. Back-fat thickness in the greatest MYI group was highly correlated to carcass weight and marbling score. The SNP array analysis identified the carcass-weight related gene BTB-01280026 with an additive effect. The steers with the allele increasing carcass weight had heavier slaughter weight of about 12 kg. Conclusion: Genetic MYI is a potential tool for calf selection, which will reduce the slaughter age while simultaneously increasing carcass weight, back-fat thickness, and marbling score.

• 한국산학기술학회논문지
• /
• 제21권11호
• /
• pp.833-842
• /
• 2020

본 연구의 목적은 국립축산과학원에서 개발한 한우 사육기간 단축기술의 경제성을 분석하여 기술보급확산을 위한 타당성을 제공하는 것이다. 한우 사육기간 단축기술은 한우 사육농가의 사료비가 경영비에서 차지하는 비중이 점점 커지고 있다는 문제점을 해결하고자 거세 한우를 대상으로 비육기간을 관행보다 단축시키면서도 육성기 고영양 사양을 통해 품질은 유지키시는 기술이다. 분석방법은 부분예산법(Partial budget analysis)을 적용하였다. 분석 결과는 다음과 같다. 첫째, 실증농가는 기술도입 전에 29개월 미만으로 출하한 성적이 0%였으나, 도입 3년차에 51.2%로, 도입 6년차에는 63.6%로 증가하였다. 둘째, 출하월령과 도체중의 연차별 성적에 대해 분산분석을 수행한 결과, 출하월령에 유의수준 0.01을 기준으로 차이가 있다는 결과를 얻었다. 또한, 도체중에서도 유의수준 0.05를 기준으로 도체중이 증가하였음을 확인할 수 있었다. 셋째, 사육기간 단축기술을 부분예산법으로 경제성을 평가한 결과, 자가 TMR 제조·급여 효과와 2개월 기단 단축효과를 합하면 최대 467,990원/두/회 수익이 발생한다는 결과를 얻었다. 본 결과는 기술보급사업에서 해당 기술이 우선적으로 보급될 수 있도록 강력한 근거자료로 활용될 수 있다. 향후 본 기술의 더 많은 보급 확대를 위해서는 시범사업 추진 이후 참여 농가와 미참여 농가를 대상으로 문제점과 한계점, 도입에 대한 장애요인 등을 추가적으로 밝혀야 할 것이다.