• Asian-Australasian Journal of Animal Sciences
• /
• 제21권2호
• /
• pp.291-298
• /
• 2008

For many years beak trimming has been a controversial subject, particularly since the 1980's when the practice came under close scrutiny by animal welfare groups. In Australia it is considered an essential practice, averting losses of AUD$17.5m annually by reducing mortality from cannibalism. While mortality in flocks from cannibalism can be reduced from 25% of the flock to virtually nil, the beak trimming procedure is considered traumatic for the bird. This study examined if chronic pain in the beak was evident in birds 10, 20 and 60 weeks after being trimmed at hatch and in another group of birds, 8 and 52 weeks after being re-trimmed at 14 weeks. Chronic pain was assessed by measuring pecking behaviour and beak sensitivity responses. Pecking behaviour studies completed after beak trimming and re-trimming showed no evidence to indicate that birds were suffering severe chronic pain in the beak. Beak trimmed pullets pecked more at the cage and had more toe pecks, yet overall pecks made at the feed and the environment were no different than untrimmed controls. While the beak sensitivity studies provided evidence that the beak of birds trimmed at hatch and also re-trimmed at 14 weeks may be more sensitive there was no evidence that re-trimming resulted in a more sensitive beak than birds trimmed at hatch only. These studies have shown that birds which are beak trimmed and re-trimmed return to apparently normal feeding and pecking behaviour in the long term. However, there was limited evidence that beaks of trimmed birds have an altered threshold to potentially painful stimuli.

• Asian-Australasian Journal of Animal Sciences
• /
• 제15권1호
• /
• pp.1-6
• /
• 2002

Eggs obtained from 46 and 42 weeks old meat (Hybro) and layer (Leghorn) breeders flocks, respectively were used to examine the effects of genetic type of birds and egg size (small, medium and large) on variables of eggshell characteristics and hatchability traits. The variables measured were egg weight (EW), egg surface area (ESA) and eggshell characteristics (shell conductance (EC), per cent shell (PS), shell thickness (ST), shell volume (SV), shell density (SD) and hatchability traits (per cent hatchability (HP), early dead embryos (ED), late dead embryos (LD), pips with live embryos (PL) and pips with dead embryos (PD)). Genetic type of bird influenced all egg characteristics and HP of eggs. Eggs produced by the small Leghorn bird had lower EW, ESA, EC, ST, SV and HP than those produced by the heavy Hybro bird. The reduction of HP was associated with an increase in the percentage of ED and PL. Egg size influenced all variables measured except ST. Small size eggs had lower EW, ESA and EC and higher PS and SD than those of large eggs. Medium size eggs produced a higher HP when compared with that of large size eggs. The reduction of HP in large eggs was associated with higher percentage of ED, LD and PL. There were significant interactions between the genetic group of birds and egg size on LD and HP. Large egg size of Hybro birds had higher LD and lower HP than those of small size eggs produced by the same flock. However, There was no difference in HP and LD among the different egg sizes produced by Leghorn birds. It was concluded that genetic make up of birds and egg size influence eggshell characteristics and HP. The type of bird (heavy or small) influences the optimum egg size for successful hatching. Attention should be given to the size and eggshell characteristics of eggs of breeders' flocks for achieving maximum HP.

• 농업과학연구
• /
• 제9권1호
• /
• pp.314-356
• /
• 1982

산란계(産卵鷄)의 주요(主要) 경제형질(經濟形質)의 효율적(效率的)인 개량(改良)을 위(爲)하여 지금까지는 체중(體重), 초산일령(初産日令), 산란계(産卵鷄) 및 난중(卵重)을 기초(基礎)로 하여 선발(選拔)하여 왔으나, 실제(實際) 가식부분(可食部分)은 난황(卵黃) 및 난백(卵白)이므로 이들에 대한 유전적(遺傳的) 모수(母數)를 추정(推定)하여 난황(卵黃) 및 난백(卵白)의 중량(重量)을 선발지수(選拔指數) 추정(推定)에 이용(利用)하므로서 선발(選拔)의 정확도(正確度)를 높일 수 있는 가능성(可能性)을 구명(究明)하기 위(爲)하여 본(本) 연구(硏究)를 실시(實施)하였다. 공시계(供試鷄)는 국립종축장(國立種畜場) 대전지장(大田支場)에서 폐쇄군(閉鎖郡) 육종방법(育種方法)에 의(依)해서 개량(改良)되어온 S. C. W. Leghorn종(種) 351수(首)와 R. I. Red종(種) 326수(首)가 사용(使用)되었고, 난구성분(卵構成分)은 총(總) 6,097개(個)가 조사(調査)되었으며, 각(各) 형질(形質)들은 1979년(年) 3월(月) 1일(日)부터 500일간(日間) 조사(調査) 분석(分析)되었다.

• 대한조선학회논문집
• /
• 제50권3호
• /
• pp.175-181
• /
• 2013

This paper presents a simulation for passenger ship evacuation considering the inclination of a ship. In order to describe a passenger's behavior in an evacuation situation, a passenger is modeled as a rigid body which translates in the horizontal plane and rotates along the vertical axis. The position and rotation angle of a passenger are calculated by solving the dynamic equations of motions at each time step. To calculate inclined angle of damaged ship, static equilibrium equations of damaged ship are derived using "added weight method". Using these equations, physical external forces due to the inclination of a ship act on the body of each passenger. The crowd behavior of the passenger is considered as the flock behavior, a form of collective behavior of a large number of interacting passengers with a common group objective. Passengers can also avoid an obstacle due to penalty forces acting on their body. With the passenger model and forces acting on its body, the test problems in International Maritime Organization, Maritime Safety Committee/Circulation 1238(IMO MSC/Circ.1238) are implemented and the effects of ship's inclination on the evacuation time are confirmed.

• Journal of Ecology and Environment
• /
• 제31권1호
• /
• pp.69-73
• /
• 2008

We studied the functional roles of two types of calls, mew calls and mobbing calls, of the black-tailed gull (Larus crassirostris) by examining responses of mixed flocks of gulls to the playback calls. Playback experiments were conducted on four days between 11 May and 5 June 2007 at 16 sites in Sinjindo-ri and Dowhang-ri, Taean-gun, Chungnam province and Imjado, Sinan-gun, Jeonnam province, South Korea. We examined the anti-predator responses of the gulls to the playback trials. We found that gull flocks initially responded to mew call playbacks by mobbing in less than half of playback trials (6/14) while all trials involving playbacks of the mobbing call and control (group mobbing) call evoked mobbing. When trials in which no response was recorded were excluded, we found that the gulls' responses to mobbing and group mobbing call playbacks was more intense than their response to mew call playbacks, in that gulls mobbed longer, more gulls responded, and gulls took flight after a shorter time interval. However, the intensity of the gulls' response did not differ in mobbing call and group mobbing call playbacks. The results of this study suggest that the mixed-species flocks of gulls discriminate between the mew calls and the mobbing calls.

• 한국게임학회 논문지
• /
• 제11권1호
• /
• pp.111-120
• /
• 2011

가상세계에서 다중 에이전트들의 집단행동을 사실적으로 시뮬레이션하는 것은 중요하다. 대부분의 기존 연구가 개방된 공간에서의 집단행동에 초점 맞춘 반면, 본 논문은 제한된 공간에서 조종력을 이용한 집단행동에 대하여 연구한다. 에이전트들은 제한된 공간에서 하나의 공동 목적지를 가지며, 다른 에이전트와 충돌을 피하면서 목적지로 이동하여야 한다. 이러한 환경에서 세 가지 가능한 에이전트 모델을 제시 하였으며, 각 모델에 필요한 여섯 가지 조종력도 제안하였다. 제안된 모델의 올바름을 보이기 위하여 모델들을 시뮬레이션 하였다. 시뮬레이션 결과는 벽들과 출입구에 따라 각 에이전트가 목적지에 도착하는 시간은 달랐지만, 단순히 조종력만을 사용하는 제안된 모델들이 제한된 공간에서 잘 동작하는 것을 보였다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제17권11호
• /
• pp.1570-1574
• /
• 2004

A flock of AA breed chickens were reared in peterstme brood-vait chamber and were provided with high energy pelleted feed. At 14 d of age, a total of 350 birds were randomly divided into 3 groups as follows: 100 birds were exposed to normal ambient temperature of 20$^{\circ}C$ for control group; 150 birds were exposed to lower ambient temperature of 11$^{\circ}C$ to induce ascites (treatment I); and another group of 100 birds were exposed to lower ambient temperature of 11$^{\circ}C$ and fed diet containing 1% L-arginine for ascitic prophylactic treatment (treatment II). Samples were collected from blood and abdominal fluid of chicken at 3, 4, 5, 6 and 7 wk of age subsequently, to analysis the contents of plasma endothelin (ET-1), angiotensin II (Ang II), cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP). The results indicated that the contents of cAMP, cGMP, and Ang II in reatment I and ascitic broilers were higher than the corresponding control group (p<0.01, p<0.05), ET-1 of preascitic broilers were control group (p<0.05), while there was an insignificant difference with later ascitic broilers. The contents of cAMP and cGMP in treatment II were higher than the treatment I and control groups (p<0.01, p<0.05), whereas, the contents of Ang II were gradually decreased compared to the control group (p<0.05), the contents of ET-1 were insignificantly different. On further analysis, the increased plasma Ang II at low ambient temperature condition in broilers made endothelium cell secretion of increased ET-1, cAMP, cGMP and decreased NO. Therefore, low temperature accelerated ascites syndrome in broilers. Supplemently L-arginine can decrease ET-1, and increase cAMP and cGMP. It is concluded that cAMP mediated in broilers pulmonary hypertension syndrome.

• Asian-Australasian Journal of Animal Sciences
• /
• 제4권4호
• /
• pp.333-339
• /
• 1991

Eighty-two ewes of Balochi breed, two to four years of age were used in a completely randomized design to study the effect of winter supplementation on their performance in Kalat area of Balochistan and randomly divided into two groups of 40 and 42 animals. Two treatments (T1 and T2) studied were : 250 gm/animal/day of a 50 : 50 mixture of cottonseed cake and barley grain fed from Oct. 20 to Dec. 18, 1988 plus grazing and 500 gm/animal/day of the same feed mixture fed from Oct. 9 to Dec. 18, 1988 in addition to grazing. Lucerne hay and wheat straw in a 50 : 50 ratio were provided to all the ewes for a period of one month from Jan. 6, 1989 @ 320 gm/animal/day to sustain them in severe winter. Same feeding levels to the same ewe groups were again fed from Mar. 1 to May 27, 1989. Three breeding rams stayed with the flock from Nov. 1 to Dec. 13, 1988. Lambing took place from Apr. 2 to May 12, 1989. Conception, lambing and mortality percentage was found different (P<.05) between T1 and T2 (12.5 vs 14.8 kg). The ewes on T2 maintained higher body weights throughout winter than the ewes on T1. The results are suggestive of improvement in conception rate with winter supplementation (flushing) and decrease in ewe mortality. Late-gestation and early-lactation supplemental feeding of ewes results in increases in weaning weights of their lambs.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권6호
• /
• pp.767-777
• /
• 2014

Characterizing local chicken types and their mostly rural production systems is prerequisite for designing and implementing development and conservation programs. This study evaluated the management practices of small-scale chicken keepers and the phenotypic and production traits of their chickens in Oman, where conservation programs for local livestock breeds have currently started. Free-range scavenging was the dominant production system, and logistic regression analysis showed that socio-economic factors such as training in poultry keeping, household income, income from farming and gender of chicken owners influenced feeding, housing, and health care practices (p<0.05). A large variation in plumage and shank colors, comb types and other phenotypic traits within and between Omani chicken populations were observed. Male and female body weight differed (p<0.05), being $1.3{\pm}0.65$ kg and $1.1{\pm}0.86$ kg respectively. Flock size averaged $22{\pm}7.7$ birds per household with 4.8 hens per cock. Clutch size was $12.3{\pm}2.85$ and annual production $64.5{\pm}2.85$ eggs per hen. Egg hatchability averaged $88{\pm}6.0%$ and annual chicken mortality across all age and sex categories was $16{\pm}1.4%$. The strong involvement of women in chicken keeping makes them key stakeholders in future development and conservation programs, but the latter should be preceded by a comprehensive study of the genetic diversity of the Omani chicken populations.

• 한국가금학회지
• /
• 제38권1호
• /
• pp.45-50
• /
• 2011

본 증례는 국내의 산란계 농장에서 사육 중이던 39일령 산란계 중추계군에서 신경 증상을 동반한 폐사를 나타내며, 부검 시 폐를 포함한 뇌, 간, 신장 등의 실질장기에서 직경 1~5 mm 크기의 황백색 결절이 다수 관찰되었다. 병리조직학적으로 다발성의 육아종성 병변이 폐, 뇌, 신장, 비장 등에서 관찰되었으며, 특히 폐의 결절 형성 및 건락성 육아종성 병변이 심한 정도로 나타나 호흡기를 통해 1차 감염이 이루어진 것을 확인할 수 있었다. 육아종성 결절을 SDA에 배양하여 집락의 색을 확인하고, 균사체의 Giemsa 염색 및 조직학적 병변상에서 PAS 염색 결과를 통해 Aspergillus 속 곰팡이인 것으로 확인할 수 있었고, 배양된 균사에 대한 유전학적 검사 결과 Aspergillus flavus로 동정되었다. A. flavus 균사는 폐, 뇌, 신장 및 선위에서 병변 중심부 및 변연부 모두에서 관찰되었고, 다핵 거대세포 및 섬유아세포가 염증세포들과 함께 둘러싸고 있는 것이 확인되었다. 특히 대뇌에서의 육아종성 병변 및 그로 인한 신경 증상이 임상 증상으로 발현된 것이 본 증례의 특징적인 소견이다.