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

• Animal Bioscience
• /
• 제36권7호
• /
• pp.1075-1082
• /
• 2023

Objective: Animal feed companies and researchers are currently embarking on quests for feed additives that could combat the pathogens while promoting growth as well as maintaining quality products. The current study aimed to evaluate the effects of onion extracts on growth performance, carcass quality, and bone morphometrics of broiler chickens. Methods: A total number of 200 one-day-old unsexed Ross 308 broiler chicks were assigned to 5 treatment groups, replicated 4 times. Each replicate (pens) held 10 chickens in a completely randomized design. The experimental diets were then randomly allotted to the pens which act as experimental units. The isoenergetic and isonitrogenous diets were formulated by including onion extracts at 0, 5, 10, 15, or 25 g/kg in a complete broiler diet. Feed intake, and body weight, were recorded then used to calculate feed conversion ratio. At the end of the experiment (42 days), four chickens from each pen were randomly selected for slaughter for carcass, bone morphology and sensory evaluation. Results: Results showed that onion extract supplementation did not affect (p>0.05) growth performances and meat sensory evaluation. However, there was a significantly increased (p<0.05) meat shear force in groups receiving onion extracts dietary treatments. Furthermore, onion extracts improved (p<0.05) bone morphology of broiler chickens in terms of weight, diameter, calcium, and phosphorous contents. Conclusion: In conclusion, onion extracts can be safely included in a commercial broiler diet as a growth promoter without causing adverse effects on growth performance traits and carcass quality in chickens. Onion extract supplementation improved tibia bone growth and strength in broiler chickens.

• 한국가금학회지
• /
• 제25권3호
• /
• pp.147-155
• /
• 1998

Dietary levels of fermented poultry manure(FPM) 0%, 5%, 10% and 20% were included in experimental diets. It is to examine the effects of diets containing different levels of FPM on the performance of broiler chicks, including the nutrient availabilities, compared with that of the commercial diet. In order to evaluate the nutritive value of FPM, feeding and metabolism trials were conducted with a total of 160 broiler chicks for a period of 4 weeks. Contents of CP, crude fat, crude ash, crude fiber and NFE of FPM were 19.43, 2.43, 15.44, 16.57 and 38.31 %, respectively. Although there were no statistical difference in the body weight gain among treatments, weight gain achieved by the group fed diets of 5% substitution of FPM was slightly better than others. The amount of feed intake was significantly higher for FPM included groups than for control group, especially in the group fed diets of 10% substitution of FPM. The feed efficiency tended to be better for the control group than the FPM groups. The feed efficiency tended to get worse as the levels of FPM increased. The digestibility of DM, CP and NFE tended to be similar among treatments, especially it was lower for the group fed diets of 20% substitution of FPM compared with that of another groups. In conclusion, up to 10% substitution of FPM to the diet can be utilized effectively as a broiler feed ingredient, without adversely affecting growth performance.

• 한국가금학회지
• /
• 제27권3호
• /
• pp.203-208
• /
• 2000

The present study was conducted to investigate the effects of dietary supplementions of 0.1% probiotic and 0.1% yeast culture on the growth performance and meat quality of broiler chicks. A total of 160 Arbor Acre broiler chicks were randomly allotted to 16 pens ; four pens per treatment and 10 birds per pen. Feeding trial lasted for 6 weeks. The results obtained are summerized as follows : The body weight gain and feed intake was slightly higher in group of broiler chick supplemented antibiotic than those of other treatment groups, but were not significantly different among treatments. The feed conversion were slightly lower in groups of broiler chick supplemented antibiotic and probiotic than those of other treatment groups, but were not significantly different among treatments. The pH of thigh musle was slightly higher in group of broiler chick supplemented probiotic than those of other treatment groups. Crude protein, crude fat and crude ash of thigh muscle were lower in groups of broiler chick supplemented probiltic and yeast culture than those of other treatment groups, but were not significantly different among treatments. The saturated fatty acid content of the thigh muscle was tende to be higher in group of broiler chick supplemented yeast culture, but the unsaturated fatty acid content was tende to be lower in group of broiler chick supplemented yeast culture than those of other treatment groups.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권3호
• /
• pp.346-350
• /
• 2001

The present study was designed to evaluate the usefulness of Sauropus. androgynus leaf (SAL) meal on reducing fat accumulation in broiler chickens. Eighty unsexed broiler chickens were allocated to four treatment groups with five replicates of four chickens each. SAL meal supplementation had no effect on body, leg, back, breast, wing, liver and heart weights, carcass protein, moisture and ash contents (p>0.05). Broilers fed diets supplemented with 30 g of SAL meal had lower feed intake with better feed conversion ratio (p<0.05) than did the control chickens. SAL supplementation at all levels significantly reduced fat accumulation in abdomen region, and liver (p<0.01), and in carcass (p<0.05). Higher SAL supplementation resulted in lower fat accumulation in the carcass ($r^{2}=0.94$; p<0.01), abdomen ($r^{2}=0.99$; p<0.01) and liver ($r^{2}=0.98$; p<0.01). The current study showed that a 30 g supplementation of SAL meal to the broiler diet was effective to improve feed conversion ratio without reducing body weight. SAL meal supplementation to the diet reduce fat accumulation in broiler chickens.

• 대한수의학회지
• /
• 제61권1호
• /
• pp.7.1-7.7
• /
• 2021

The levels of aflatoxin (AFT) and ochratoxin (OCT) were assessed at different seasons in raw materials, different feed manufacture processing stages, and animal feeds in feed mills in Korea implementing the hazard analysis and critical control point (HACCP) system. Two hundred samples were collected in all four seasons from five feed mills implementing the HACCP system and examined for AFT and OCT contents. The AFT and OCT levels were analysed by using HPLC method to provide information on raw material and product stage. The AFT content of raw ingredients in the spring season was highest in corn gluten (3.84 ppb) and lowest in corn (1.82 ppb) The AFT content of corn was highest in the winter season (2.17 ppb). The content of OCT in wheat was highest in the winter season. The amounts of AFT and OCT at processing stages were higher than in the raw materials or feed. In particular, AFT content was higher in the transfer stage (3.88 ppb) than in the mixing (2.86 ppb) or filling stages (3.45 ppb) in the summer season. The means of AFT and OCT level in laying hen feed was 3.41 ppb and 1.14 ppb for broiler feed, respectively. The means of AFT and OCT level in and broiler feeds was 3.44 ppb and 1.17 ppb for broiler feed, respectively.

• 한국가금학회지
• /
• 제17권1호
• /
• pp.33-44
• /
• 1990

본 연구는 육계와 육용오리의 도체특성을 비교하고 육계의 성, 사육형질, 계절 및 절식시간에 따른 도체율과 복강지방축적률을 조사하기 위하여 육계 240수와 육용오리 20수에 대한 도체조사기록을 이용하여 연구하였는바 그 결과를 요약하면 다음과 같다. 1. 육계와 육용오리의 도체률은 각각 65.43%와 66.79%였으며, 복강지방축적률은 육계가 육용오리가 비하여 현저하게 높았다. 2. 육계와 육용오리의 부분육 생산비율은 현저한 차이가 있었으며, 육계의 경우 부분육 생산비율은 다리, 가슴, 등, 날개 및 목의 순서로 높았다. 3. 육계의 도체율은 성별에 따라 차이가 없었으나 복강지방축적율은 암컷이 수컷에 비하여 현저하게 높았다. 4. 사육형태간에 도체율은 차이가 없었으나 복강지방축적율은 케이지가 평사에 비하여 다소 높은 경향이었다. 5. 사육계절간에도 도체율은 차이가 없었으나 복강지방축적률은 하계에 가장 높았고 동계에 가장 낮았다. 6. 절식ㆍ절수시간이 1시간 경과함에 따라 육계의 체중은 약0.28365%씩 감소하였으며, 도체율은 절식 6시간 후 가장 높았다.

• 한국가금학회지
• /
• 제21권2호
• /
• pp.83-92
• /
• 1994

In order to study performance enhancing effects of supplementary antibiotics (avoparcin, nosiheptide and enramycin), two feeding trials were conducted. In Experiment 1, 1, 040 male Arbor Acres were reared in floor pens for 6 wk. Chicks were assigned to one of the following four treatments: Basal diet(B), B+avoparcin 10 ppm, B+nosiheptide 2.5 ppm and B+enramycin 5 ppm. Each treatment had five replications of 52 chicks each. In Experiment 2, two antibiotics (avoparcin and enramycin) were compared in $2{\times}2$ (antibiotics$\times$sex) factorial design. One thousand broiler chicks were reared in floor pens for 6 wk. Each of the 4 treatments had five replications of 50 chicks each. The results of Experiment 1 showed that antibiotic treatments (enramycin, avoparcin and nosiheptide) significantly(P <0.05) improved weight gain. Feed/gain ratio of avoparcin treatment and enramycin treatment tended to he lower than the control but they were not statistically significant. Dressing percentages were high in avoparcin and enramycin treatments compared to the control and nosiheptide treatment. The number of E. coli and Cl. perfringens in ileum and cecal contents were decreased by antibiotic treatments. Moisture contents in excreta of the birds were not significantly affected by the treatments. Leg abnormality and mortality were not significaniy different among treatments. In Experiment 2, weight gain was significantly (P<0.01) different between sexes, but not between antibiotic treatments. Significant effects of antibiotics (P<0.01), sex (P<0.01) and interaction (P<0.05) were shown in feed in take. Feed/gain ratio of avoparcin treatment was significantly (P<0.01) lower than that of enramycin treatment. leg abnormality and mortality were not significantly different among treatments but those in male broiler tended to be higher than in female broilers. It was concluded that nonsystemic antibiotics supplemented to the broiler diets suppress undesirable microorganisms and improve broiler performace in general and avoparcin was most effective in improving feed/gain ratio.

• Animal Bioscience
• /
• 제35권12호
• /
• pp.1904-1910
• /
• 2022

Objective: This study aimed to investigate the effects of corticotropin-releasing factor (CRF) on the feed intake of broiler chickens and explore its influencing mechanism. Methods: The study included two trials. In trial 1, 32 male broiler chickens (Arbor Acres, Gallus gallus domesticus) were given ventricle buried tubes, and they were allowed to recover for 3 days. At 8:00 AM, intracerebroventricular (ICV) injection with CRF or normal saline was performed in 10-day-old broiler chickens, which were divided into the 5, 10, and 20 ㎍ and control (normal saline) groups according to the dose of CRF injection. In trial 2, chickens were divided into the 10 ㎍ and control group (physiological saline) to repeat trial 1. Results: Results of trial 1 showed that the cumulative amount of feed intake in the 10 or 20 ㎍ groups was considerably lower than that of the control group after ICV injection with CRF. The lowest amount of feed intake was obtained with the addition of 10 ㎍ of CRF. In trial 2, the expression of ghrelin in the hypothalamus injected with 10 ㎍ of CRF increased significantly, but the expression of ghrelin in various sections of the small intestine considerably decreased. The expression of CRF receptor subtypes 1 (CRFR1) in the hypothalamus and some parts of the small intestine remarkably increased, and the expression of CRF receptor subtypes 2 (CRFR2) increased only in the duodenum, whereas the expression of growth hormone secretagogue receptor (GHSR-1α) in the jejunum and ileum increased considerably after ICV injection of 10 ㎍ of CRF. Conclusion: The CRF at 10 ㎍ increased ghrelin expression in the hypothalamus and CRFR1 expression in the small intestine, and this phenomenon was related to the suppressed feed intake of broiler chickens.

• 한국환경과학회지
• /
• 제30권11호
• /
• pp.979-982
• /
• 2021

This study was conducted to investigate the effects of adding Tenebrio molitor L Powder to broiler feed on fatty acid profiles in broiler breast meat. In total, 180 broiler chicks (1-day old Arbor Acres) were included. The birds were randomly divided into control and treatment groups, with 3 replicate subgroups each(30 birds per subgroup), and fed a diet for 35 days without (control) or with 1% Tenebrio molitor L powder (treatment). Among individual fatty acids, addition of Tenebrio molitor L. powder resulted in slightly higher C18:1n-9, C20:3n-3 and C20:3n-6 contents, and lower C18:2n-6 content compared withcontrols (p<0.05). No remarkable differences in total SFA and total USFA contents were found between groups. In conclusion, inclusion of Tenebrio molitor L. in broiler diets did not improve overall fatty acid profiles.