• Asian-Australasian Journal of Animal Sciences
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• v.20 no.7
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• pp.1084-1091
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• 2007

Different levels of dietary mannanoligosaccharide (Bio-MOS, Alltech Inc.) were evaluated for their efficacy on performance and gut development of broiler chickens during a 6-week experimental period. Experimental diets contained (g MOS/kg diet) a low (0.5 g during the entire period), medium (1 g during the entire period), high (2 g during the entire period), or step down (2 g in the first week; 1 g in the second and third week; 0.5 g in the last three weeks) level of MOS. Control diets included a negative and a positive control (zinc bacitracin, ZnB, 50 ppm and 30 ppm in the first and last three weeks, respectively). MOS supplementation improved the growth performance of young birds and the effects became less when the birds got older. The growth response of birds was more obvious at the high dosage level of MOS treatment than the other MOS treatments and the growth performance of birds fed on the high MOS diet was comparable to that of birds fed on the ZnB diet. Depending on the dosage level and the age of birds, MOS seemed to reduce the size of the liver and the relative length of the small intestine but did not affect the relative weight of the other visceral organs (proventriculus, gizzard, pancreas, bursa and spleen) and that of the small intestine. A numerical increase in the small intestine digestibility of nutrients was noticed in the young birds fed on the MOS diet(s), but not in the older ones. Medium and/or high MOS treatment also increased the villus height of the small intestine of birds at different ages. Similar results were observed on the ZnB treatment. However, MOS and ZnB affected caecal VFA profile in different ways. MOS increased, or tended to increase, whereas ZnB reduced individual VFA concentrations in the caeca.

• Journal of Animal Science and Technology
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• v.58 no.3
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• pp.12.1-12.7
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• 2016

Background: The objective of this experiment was to investigate the effects of dietary supplementation of rice bran oil (RBO) on growth performance, blood parameter, and immune response in broiler chickens. Methods: A total of 240 1-d-old ROSS 308 male broilers were randomly allotted to 4 dietary treatments with six replicated pens consisting of ten chicks. The basal diet was formulated to be adequate in energy and nutrients. Three additional diets were prepared by adding 5, 10 or 20 g/kg of RBO to the basal diet. The experimental diets were fed on an ad libitum basis to the birds during 35 d. Results: Results indicated that increasing inclusion level of RBO in diets improved BW gain (linear and quadratic, P < 0.01), improve feed conversion ratio (linear, P < 0.05) of birds during 0 to 35 d. There was no effect of inclusion level of RBO in diets on feed intake of birds. There was no effect of inclusion level of RBO in diets on erythrocytes of birds. However, heterophil, lymphocyte, and monocytes increased (linear and quadratic, P < 0.01) with inclusion level of RBO in diets increased. Feeding the diets containing increasing amount of RBO to birds increased (linear, P < 0.01) the concentrations of total cholesterol. Increasing inclusion level of RBO in diets increased concentrations of IgG (linear, P < 0.01). There was no effect of inclusion level of RBO in diets on concentrations of IgM. Conclusions: These results suggest that dietary RBO may be used functional ingredient to improve growth performance, total cholesterol in serum, and immune response of birds.

• Korean Journal of Poultry Science
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• v.43 no.3
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• pp.169-176
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• 2016

An experiment was conducted to evaluate the growth performance and meat quality traits of broilers fed a diet supplemented with dry-ground curry leaves (Murraya koenigii). A total of 750 one-day-old broiler chicks (Cobbs 500) were arranged in the experiment with a completely randomized design and allotted to one of five treatments, with $T_1-Control$ and $T_2-T_5$ curry leaves powder levels (i.e., 0.3%, 0.6%, 0.9% and 1.2%, respectively). The initial body weights, final body weights and daily feed intake were measured over an experimental period of 32 days. At the conclusion of the experiment, the carcass weights and meat quality parameters were measured. The birds fed diets supplemented with curry leaves powder had a higher weight gain (P<0.05; ADG), improved feed conversion ratio (P<0.05; FCR) and lower mortality (P<0.05) rates compared to the birds in the control group. Nonetheless, there was no difference (P>0.05) in feed intake among the dietary treatments. Similarly, supplementation of curry leaves powder had no effect (P>0.05) on the proportions of the carcass, leg meat and drumstick. No differences were (P>0.05) observed in cooking loss or the pH of meat from broilers fed the curry leaves supplemented diet. However, curry leaf supplementation affected (P<0.05) the meat water holding capacity. A sensory evaluation showed higher levels of taste and tenderness in meat from broilers fed with curry leaves powder. In conclusion, our results suggested that curry leaves powder improved the growth performance of broilers, with a lower incidence of mortality and improvement of some meat qualities.

• Animal Bioscience
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• v.34 no.8
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• pp.1365-1374
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• 2021

Objective: This study was conducted to investigate the synergistic effect of exogenous multienzyme and phytase on growth performance, nutrients digestibility, blood metabolites, intestinal microflora, and morphology in broilers fed corn-wheat-soybean meal diets. Methods: A 2×2 factorial design was used in this study. Four dietary treatments consisted of i) basal diets (corn-wheat-soybean meal based diets without multi-enzyme and phytase), ii) basal diets with phytase (0.05%), iii) basal diets with exogenous multi-enzyme (0.05%), and iv) basal diets with exogenous multi-enzyme including phytase (0.05%). A total of 480 broiler chickens (Ross 308 - one day old) were weighed and allotted to thirty-two cages (15 birds per cage), and chicks were randomly allocated to four dietary treatments. Results: The body weight gain and feed conversion rate were improved by supplementation of exogenous multi-enzyme containing phytase during the finisher period (p<0.05). The birds fed diets with exogenous multi-enzyme containing phytase had a significantly greater digestibility of dry matter, gross energy, crude protein, calcium, and phosphorus compared with birds fed non-supplemented diets (p<0.05). The chickens fed diets with exogenous multi-enzyme containing phytase showed a higher concentration of Ca and P in the serum (p<0.05). The population of Lactobacillus spp., Escherichia coli, and Clostridium were not affected in the ileum and cecum of chickens fed enzyme-supplemented diets. The dietary supplemental exogenous multi-enzyme containing phytase showed a significant improvement in villus height, crypt depth, and villus height and crypt depth ratio, compared to basal diets or dietary supplemental phytase (p<0.05). Conclusion: The supplementation of the exogenous multi-enzyme containing phytase synergistically improved the growth performance, nutrients digestibility, and villus height of the small intestine of broiler chickens fed a corn-wheat-soybean meal based diets.

• Animal Bioscience
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• v.35 no.8
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• pp.1215-1222
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• 2022

Objective: A feeding trial was carried out to determine the effect of dietary inclusion of silymarin seed extract on growth performance, nutrient digestibility, excreta microbiota, excreta gas emission, blood profiles, and meat quality in broilers. Methods: A total of 1,088 one-day-old Ross 308 broiler chicks (mixed-sex) with an initial body weight of 42.34±0.82 g, were randomly allocated into 1 of 4 dietary treatments with 17 replicates of 16 chicks per cage and fed a basal diet supplemented with 0%, 0.02%, 0.04%, and 0.06% of silymarin. Results: The inclusion of silymarin supplementation linearly increased the body weight of broilers during days 7 to 21 and 1 to 35 days. On day 35, broilers fed a diet containing graded levels of silymarin supplementation linearly increased the nutrient digestibility of dry matter, gross energy, and nitrogen and cecal Lactobacillus counts (p = 0.038). While silymarin supplement linearly reduced the methyl mercaptans (p = 0.039) and acetic acid (p = 0.007) emission in broilers. No significant effects were observed on the blood profile. Relative weights of organs such as breast muscle, bursa of fabricius were increased (linear effect, p<0.05), water holding capacity was enhanced by increasing the silymarin level from 0% to 0.06%. A linear reduction (p>0.05) in drip loss from meat samples during days 1, 3, 5, and 7 by the addition of graded level of silymarin to the diet. Conclusion: An increasing level of silymarin supplementation to the diet of broiler would be beneficial to enhance growth performance, nutrient digestibility, excreta microflora, blood profile, and meat quality traits.

• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.255-265
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• 2021

Global warming and scorching summer seasons affect the growth ability of broilers and animal welfare. In modern broilers, vital organs, such as the heart and lungs, grow disproportionally under intensive selection, making it difficult to adapt to warmer climates. Changes in environmental temperature can affect muscle formation during embryonic development and the early posthatching period. Satellite cells are highly sensitive to heat stress. Heat stress affects the proliferation and differentiation activity of satellite cells and muscle growth and structure. Therefore, thermal manipulation during broiler chick embryogenesis and environmental temperature management at the beginning of hatching are critical for the development and growth of broiler muscles. This review focuses on the thermoregulation mechanism of birds, the muscle development process of broilers, and the function of satellite cells, the relationship between heat stress and muscle development of chicks shortly after hatching, and studies on heat resistance and muscle growth of broilers.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.719-727
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• 2021

This study was conducted to evaluate the effects of mixed and separate gender feeding on the growth performance and carcass traits of Korean native chickens (KNC) compared to white semi-broilers (WSB) and a commercial broiler (CB) from hatching to 35 days. Here, 240 chicks were used with eight birds per cage in a randomized design with six replicates per breed. For the KNC lines, three groups of males (KNC-M), mixed-gender birds (KNC-FM) and females (KNC-F) were used. The two-phase feeding program used here consisted of a starter phase (days 1 - 21: crude protein [CP] 20% and metabolizable energy [ME], 3,050 kcal·kg^-1) and a grower phase (days 22 - 35: CP 18%, 3,100 kcal·kg^-1) for a commercial broiler. The WSB and CB were fed the only starter commercial diet. Fresh water and feed were provided ad-libitum. The results revealed that the KNC group had a lower (p < 0.05) body weight (BW) from day 7 and day 35 compared to that of the CB. Furthermore, the KNC group showed a lower (p > 0.05) average daily gain (ADG) relative to that of the CB during the entire experimental period. No difference (p > 0.05) was observed in the shank length among the treatments. There were also no significant differences in the growth performance or carcass traits between the KNC-M and WSB groups or in the genders of the KNC group.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.772-775
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• 1999

A six week growth performance trial involving 450 birds was conducted to determine the dietary requirement of broiler chicks for available methionine (AM). Body weight gain was significantly (p<0.01) lower on high AM diet (1411 g/bird) than low AM (1470 g/bird) and normal AM (1466 g/bird) diets. The feed intake by birds ranged from $3241{\pm}25.69$ in high AM diet to $3321{\pm}25.69g/bird$ in low AM diet. The feed efficiency for the three diets having low, normal and high level of AM were $2.26{\pm}0.02$, $2.24{\pm}0.02$ and $2.30{\pm}0.02$, respectively. The results indicated that the birds fed high AM diet consumed significantly (p<0.01) more feed per unit body weight gain as compared to birds on low and normal AM diets.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.116-121
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• 2013

The effects of oligosaccharide supplementation on the growth performance, flock uniformity and GIT development of broiler chickens were investigated. Four diets, one negative control, one positive control supplemented with zinc-bacitracin, and two test diets supplemented with mannoligosaccharide (MOS) and fructooligosaccharide (FOS), were used for the experiment. Birds given MOS or FOS had improved body weight (BW) and feed efficiency (FCR), compared to those fed the negative control diet during the 35-d trial period. The effect on FCR became less apparent when the birds got older. FOS and MOS supplementation reduced the pancreas weight as a percentage of BW, with an effect similar to that of the antibiotic, at 35 d of age. Birds given MOS tended to have a heavier bursa (p = 0.164) and lower spleen/bursa weight ratio (p = 0.102) at 35 d of age. MOS and Zn-bacitracin showed a clear improvement on flock uniformity, compared to FOS. The mortality rate was not affected by FOS or MOS.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.384-389
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• 2016

A total of 400, one day-old commercial broiler chicks were divided into five diet groups (negative control, positive control group with 55 ppm Zn-bacitracin, 15 ppm ${\beta}$-glucan, 30 ppm ${\beta}$-glucan, and 60 ppm ${\beta}$-glucan) and fed for six weeks. Ten broilers were allotted to each of 40 floor pens. Eight floor pens were randomly assigned to one of the 5 diets. Each diet was fed to the broilers for 6 weeks with free access to water and diet. The survival rate, growth rate, feed efficiency, and feed conversion rate of the broilers were calculated. At the end of the feeding trial, the birds were slaughtered, breast muscles deboned, and quality parameters of the breast meat during storage were determined. The high level of dietary ${\beta}$-glucan (60 ppm) showed better feed conversion ratio and survival rate than the negative control. The survival rate of 60 ppm ${\beta}$-glucan-treated group was the same as that of the antibiotic-treated group, which showed the highest survival rate among the treatments. There was no significant difference in carcass yield, water holding capacity, pH, color, and 2-thiobarbituric acid reactive substances values of chicken breast meat among the 5 treatment groups. Supplementation of 60 ppm ${\beta}$-glucan to broiler diet improved the survival rate and feed conversion rate of broilers to the same level as 55 ppm Zn-bacitracin group. The result indicated that use of ${\beta}$-glucan (60 ppm) can be a potential alternative to antibiotics to improve the survival and performance of broilers. However, dietary ${\beta}$-glucan showed no effects on the quality parameters of chicken breast meat.