• 한국축산식품학회지
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• 제24권2호
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• pp.202-208
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• 2004

이 총설은 출하 전 절식에 관한 문헌을 요약 정리한 것이다. 도축 시 도체 오염 방지는 효과적인 절식 프로그램을 실시할 때만이 가능하다. 특별히 법으로 외견 또는 미생물적 오염을 규제하는 나라의 경우 절식은 매우 중요하다. 육계에 대한 절식은 도축 시 장 내용물로부터 도체 오염을 줄일 수 있어 이를 권장하고 있다. 대부분의 연구가 적정한 절식 시간, 도축, 가공의 효율성 유지 및 닭고기 안전성을 확보하기 위한 수단으로서의 절식 효과에 대해 초점을 두고 진행되었다. 실제적인 절식 프로그램은 생축생산 능력과 사육방식, 도축방법, 도축검사 및 도축관련 규정이 달라 나라마다 다르다는 점을 지적한다.

• Nuclear Engineering and Technology
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• 제55권4호
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• pp.1225-1232
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• 2023

The ¹⁸⁰W is the lightest isotope of Tungsten with small abundance ratio. It is slightly radioactive (α decay), with an extremely long half-life. Its separation is possible by non-conventional single withdrawal cascades. The ¹⁸⁰W is used in radioisotopes production and study of metals through gamma-ray spectroscopy. In this paper, single withdrawal cascade model is developed to evaluate multicomponent separation in non-conventional transient cascades, and available experimental results are used for validation. Numerical studies for separation of ¹⁸⁰W in a transient single withdrawal cascade are performed. Parameters affecting the separation and equilibrium time of cascade such as number of stages, cascade arrangements, feed location and flow rate for a fixed number of gas centrifuges (GC) are investigated. The Salp Swarm Algorithm (SSA) as a bio-inspired optimization algorithm is applied as a novel method to minimize the feed consumption to obtain desired concentration in the collection tank. Examining different cascade arrangements, it is observed in arrangements with more stages, the separation is further efficient. Based on the obtained results, with increasing feed flow rate, for fixed product concentration, the cascade equilibrium time decreases. Also, it is shown while the feed location is the farthest stage from the collection tank, the separation and cascade equilibrium time are well-organized. Finally, using SSA optimal parameters of the cascade is calculated, and optimal arrangement to produce 5 gr of ¹⁸⁰W with 90% concentration in the tank, is proposed.

• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.106-111
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• 2007

The current study was conducted to determine the optimum length of feed withdrawal for pre-harvest broilers. A total of three hundred broilers were sampled from an industrial population, and 30 chicks for each weight group (e.g., 1.5 and 2.5 kg) were randomly assigned to feed withdrawal treatments for 0, 3, 6, 9 and 12 h. Weight loss, yield, muscle pH, objective meat color and weights of gastro intestinal contents, crop, gizzard, provenriculus, small intestine, caecum, and rectum were determined. Live weight loss was significantly (p<0.05) increased as length of feed withdrawal extended. A significant (p<0.05) carcass yield for both 1.5 and 2.5 kg groups coincided after 9 and 6 h feed withdrawal, respectively. Net weights of intestinal contents for crop and gizzard were significantly (p<0.05) reduced by 6 h, and the reduction for proventriculus and small intestine occurred from 3 h. A noticeable effect of feed withdrawal on pH for breast muscle at 3 h postmortem occurred only when chicks were fasted for 3 h of which pH (6.05) was significantly (p<0.05) higher than that for other groups including the control (5.74). There was a linear tendency of higher lightness (Hunter L* value) numerically for chicks fasted for longer periods. The highest coefficient of determinations of regression models to estimate weight loss as a function of fasting period and body weights were achieved, when the models included both linear and quadratic terms for fasting period, and linear term for both 1.5 ($R^2=0.76$) and 2.5 kg ($R^2=0.78$) body weight groups. Given the practical aspect, approximately 1.5 kg of body weight is dominant, weight loss could be predicted by the following function; live weight $loss=26.6-0.28{\times}(fasting period)^2+12.34{\times}pasting\;period-0.012{\times}body\;weight$, $R^2=0.76$. Current data implied that the optimum fasting time for pre-slaughter chicks varied depending on slaughter weight; 6 and 9-h fasting were recommendable for 2.5 and 1.5 kg chicks, with little effect on objective meat color.

• Animal Bioscience
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• 제34권6호
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• pp.1070-1077
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• 2021

Objective: An experiment was conducted to determine the appropriate fasting time prior to slaughter for broilers in floor-feed and scatter-feed mode. Methods: On 21 d since hatching, 120 Arbor Acres broilers were divided into floor-feed and scatter-feed groups, chicks from each group were further assigned to feed withdrawal treatments for 0, 4, 6, 8, and 10 h. Some resultant indicators such as carcass contamination, body weight loss, meat quality of 54-day-old broilers were measured. Results: It appears that longer feed withdrawal increased weight loss, lightness, drop loss of meat but reduced pH. A significant higher weight loss and lightness for both floor-feed and scatter-feed chicks coincided after 6 to 10 h feed withdrawal (p<0.05). pH for breast muscle at 45 min postmortem reduced when chicks of scatter-feed were fasted 6 and 10 h, while the reduction of floor-feed group occurred only in 10 h (p<0.05). A noticeable effect of feed withdrawal on drop loss occurred after 10 h fasting in scatter-feed of which drop loss were significantly higher than that for other groups including control (p<0.05). The change of contamination propensity revealed that 6 to 10 h fasting significantly reduced the likelihood of carcass contamination under both floor-feed and scatter-feed (p<0.05). Net weights of intestinal contents for gizzard were significantly reduced after feed deprived for 10 h in floor-feed and 6 and 10 h in scatter-feed (p<0.05). The decrease for whole intestine occurred after floor-feed broilers have been without feed for more than 4 h, scatter-feed broilers for more than 8 h (p<0.05). Conclusion: On the premise that poultry product properties and welfare were not significantly damaged, proper fasting time could reduce carcass contamination. Current data implied that 6 h fasting was recommendable for both floor and scatter feed pre-slaughter broilers.

• 한국가금학회지
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• 제48권4호
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• pp.287-295
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• 2021

본 연구는 농장 단계에서의 절식 시간에 따른 육계의 중량 및 소화기관의 무게의 변화, 소낭 내 Salmonella, Campylobacter 오염, 혈액 매개변수, 계육 품질에 미치는 영향을 알아보기 위하여 수행하였다. 총 100 수의 육계(초기생체중, 1.906±0.06 kg)를 무작위로 5개의 처리구에 나누어 배치하였다. 절식 기간 동안 물은 공급했지만 사료는 공급하지 않았다. 절식 시간은 2, 3, 4, 5, 6시간으로 설정하였다. 생체중, 도축 전 체중, 도체중, 소화기관의 무게, 소낭 내 Salmonella 및 Campylobacter 수, 혈청 생화학적 조성, 백혈구, 적혈구, 혈소판 및 계육 품질을 분석하였다. 본 연구 결과 절식시간에 따른 도체중, 혈액 corticosterone, 가슴육 pH, 육색, 보수력에 유의적인 차이를 나타내지 않았다. 하지만, 6시간 절식한 육계의 소장 내 Salmonella 균 수가 유의적으로 낮았으며, 전단력은 유의적으로 가장 높았다. 6시간 동안 절식한 육계의 가슴육의 전단력은 증가하였으나 소비자의 관능적 특성에는 영향을 미치지 않았으며, Salmonella 균 오염도 감소하여 도계 시 오염도가 감소할 것으로 사료된다. 본 연구 결과는 농장단계에서의 절식시간 설정에 대한 참고 자료가 될 수 있을 것으로 사료되며, 향후 운송, 계류 시간도 함께 고려한 총 절식 시간에 대한 연구도 필요할 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1445-1450
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• 2005

This experiment was conducted to evaluate the effect of feed withdrawal (F) and heat acclimatization (A) on malebroiler and -layer chickens responses to acute heat stress (AHS) at four weeks of age. Totals of ninety male chicks of broiler or layer type were randomly allocated into 30 pens of grower batteries with raised wire floors. Chicks were subjected to F and A three times a week through the first three weeks of age. At each time, feed withdrawal and heat acclimatization (T = $35^{\circ}C$) lasted for six and four hours, respectively. Feed consumption (FC), body weight (BW), and feed conversion ratio (FCR) were recorded weekly for broiler type chickens only. At four weeks of age, all groups of chickens were exposed to AHS (T = $39{\pm}1^{\circ}C$) for three hours. Before and after AHS challenge, body temperature (Tb), heterophil (H), and lymphocyte (L) counts were recorded, and H/L ratio was calculated. Antibody (Ab) response to sheep red blood cells (SRBC) was assessed from all treatments without being exposed to AHS. Group F of broiler-type chickens weighed less (p<0.05) compared to control group. Also, both A and F groups of broiler-type chickens consumed less (p<0.05) feed when compared to control group. Acute heat stress elevated Tb of all treatment groups, however the increase was more profound (p<0.001) in broiler chicks. Broiler chicks of both A and F groups showed a tendency to have higher (p = 0.08) Tb when compared to control group. Acute heat stress elevated (p<0.001) H/L ratio in both types of chickens. Broiler chicks maintained higher (p<0.001) H/L ratio. Both F and A groups reduced (p<0.01) the level of elevation in H/L ratio compared to control groups of both types of chickens. Neither A nor F group affected the Ab production in response to SRBC. However, there was a tendency towards higher Ab responses in F group when compared to other groups in both types of chickens. Results of the present study demonstrate that previous history of feed withdrawal or episodes of heat exposures improved chicks'physiological withstanding of AHS and a tendency to improved humoral immune response.

• 한국가금학회지
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• 제29권1호
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• pp.37-43
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• 2002

본 시험은 왕겨에 의한 사료의 희석과 무급여일 설정방법에 의한 조기제한사양이 육계의 보상성장과 사료효율 및 체지방 축적에 미치는 영향을 구명하기 위해 7일령된 무감별 육계 300수를 5처리 3반복, 반복당 20수씩 공시하여 7일령에서부터 49일령까지 실시하였다. 대조구(C)는 7일령부터 49일령까지 전기간 육계 전기사료와 후기사료를 자유채식을 시켰으며, 시험구(71-74)들은 모두 7일령부터 14일령까지 육계전기사료와 왕겨를 50:50(wt/wt)으로 혼합한 희석사료를 급여하였으며, 제한사양기간동안 T1은 희석사료를 자유채식시켰으며, T2는 1일절식-3일급여, T3는 1일절식∼2일급여 및 T4는 1일절식∼1일급여하였고, 제한 사양이 끝난 시험구들은 전기사료 및 후기사료를 자유채식시켰다. 제한사양기간을 포함한 21일령까지의 증체량과 21일령 체중 모두 T1은 대조구와 유의적 차이가 없었으나 다른 시험구들은 대조구보다 적었다(P<0.05). 22일령부터 49일령가지의 증체량은 T1구가 대조구와 유의적인 차이는 없었으나 가장 높은 증체를 보였다. 전기간인 7일령부터 49일령 까지의 증체량과 49일령 체중도 T1구만 대조구와 유의적인 차이가 없었고 다른 시험구들은 대조구보다 적었다(P<0.05) .제한사양후부터 21일령까지의 사료섭취량은 T1구를 제외한 나머지 시험구에서는 대조구에 비해 유의적으로 적었으며 (P<0.05) , 전기간 셥취량도 T1구만 대조구와 유의적인 차이를 보이지 않았으나, 희석사료섭취기간의 왕겨섭취량을 제외한 육계사료 섭취량에서는 모든 시험구들이 대조구에 비해 유의적으로 적게 섭취하였다(P<0.05) 제한사양기간을 포함한 7일령부터 21일령까지의 사료요구율은 T1구와 T2구가 대조구에 비해 유의적으로 높았으며(P<0.05), 22일령부터 49일령가지의 사료요구율은 대조구에 비해 모든 시험구들이 유의적으로 낮았으며(P<0.05), 전기간동안의 사료요구율은 T1구를 제외한 나머지 시험구들은 대조구에 비해서 유의적으로 낮았으나(P<0.05) , 희석사료섭취기간의 왕겨섭취 량을 제외 한 육계 사료요구율은 대조구에 비해서 모든 시험구들이 유의적으로 낮거나(P<0. 05) 낮아지는 경향을 보였다. 복강내 지방함량 및 전기간 폐사율은 처리간에 유의적 차이가 없었다.

• 한국잠사곤충학회지
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• 제53권2호
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• pp.78-81
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• 2015

본 연구는 사육용 쌍별귀뚜라미의 배변제거를 위한 절식시간을 알아보는 것을 실험 목적으로 하였다. 귀뚜라미는 현재 드디어 한시적 식품인정을 받았다. 따라서 식용 곤충으로서 국내시판을 위한 연구의 일환으로 귀뚜라미 생체 안의 배변을 제거하여 미생물의 번식을 예방하고 이취 제거와 맛을 향상시키기 위하여 본 쌍별귀뚜라미의 절식 실험을 실시한 결과 농가와 실험실에서 두 곳 모두 절식 2일째부터는 귀뚜라미의 습성에 의해 동족포식의 카니발리즘이 발동하여 귀뚜라미의 생체가 훼손되어 나감을 관찰 하였다. 쌍별 귀뚜라미 장내 분변을 현미경으로 살펴본 결과 1일째 이후 분변은 거의 없어지고 싸움으로 획득한 귀뚜라미의 팔다리 일부가 장내에 들어 있는 양상을 보여 1일이 귀뚜라미 장내 변이 거의 없어지는 시간임을 알 수 있어 생체 운송 배달시 1일이 걸리는 기간을 감안하면 절식시간은 1일이 적당하다고 사려 되어진다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.233-243
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• 1999

Food safety or sanitation are terms broadly applicable to procedures designed to ensure that food quality is high and free of factors which may adversely affect human health. These factors include zoonotic diseases and acute and chronic effects of ingesting natural and human-made xenobiotics. Use of drugs in animal production for the treatment and control of animal diseases, to promote growth rate, and to improve feed conversion efficiency has expanded year by year, thus increasing the possibilities for occurrences in animal products of residues harmful to humans. Governmental agencies have made efforts to control or prevent residue problems. The Korean Food and Drug Administration (KFDA) is charged with the responsibility of establishing tolerances for veterinary drugs, pesticides, and mycotoxins and other non-pharmaceutical substances. The Department of Veterinary Service is responsible for establishing guidelines regarding withdrawal times of drugs, approval of drugs, their uses, and sanitation enforcement of livestock products. The authors describe the toxicological basis for the establishment of tolerance levels for xenobiotics and the pharmacokinetic basis for establishing withdrawal time for veterinary drugs. The regulatory tolerance levels of chemicals in pork and swine feed, Korean regulations on the use of feed additives, rapid residue test methods, the National Residue Program, and the Food Animal Residue Avoidance Databank are discussed. Rapid EIA methods that are under development for the screening of live animals are described These methods predict tissue residues from an examination of blood samples taken from pigs before they are slaughtered.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.412-417
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• 2006

This study evaluated the effectiveness of different arsenical sources on inducing fatty liver, on changes in lipid metabolism and on liver function in mule ducks. Sixty twelve-week-old mule ducks were selected and randomly divided into five treatments, including the control group and four different arsenical sources; Roxarsone (300 mg/kg), arsanilic acid, $As_2O_5$ or $As_2O_3$, containing 85.2 mg/kg arsenic were included in the basal diet. The ducks were fed the medicated basal diet for 3 weeks followed by a one-week drug withdrawal. The results showed Roxarsone treatment decreased body weight, feed intake, liver weight and abdominal fat weight (p<0.05), while it increased the relative liver weight (p<0.05) during medication period ($3^{rd}$ week). The $As_2O_5$ treatment decreased abdominal fat weight and relative abdominal fat weight when compared to the control (p<0.05). Only Roxarsone among the treatment groups increased feed intake, liver weight and relative liver weight, while the $As_2O_3$ group showed the lightest liver weight and relative liver weight among treatment groups during the withdrawal period ($4^{th}$ week). The Roxarsone group decreased (p<0.05) NADP-malic dehydrogenase (MDH) and acetyl-CoA carboxylase (ACC) activities and increased (p<0.05) cholesterol concentration during the medication period, and elevated the MDH and ACC activities during the withdrawal period. All four arsenical treatment groups showed lymphocytic infiltration in liver tissue, while the Roxarsone and $As_2O_3$ treatments showed an increase in aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) activities (p<0.05). During the withdrawal period, arsenical treatments resulted in liver vacuoles. However, the arsenicals differed in effectiveness and mechanisms of inducing fat vacuoles.