• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1753-1762
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• 2019

Objective: The study was aimed to compare carcass traits, physicochemical and textural properties of meat in two different genotypes of Pekin ducks with regard to sex effect. Methods: The study involved 120 Pekin ducks: 30 males and 30 females of strain P33 (Polish native Pekin ducks) and 30 males and 30 females of Star 53 HY (commercial hybrid Pekin ducks). At 49 d of age, 48 birds (12 males and 12 females of each genotype) were selected for dissection. After the dissection, meat samples were collected to determine meat quality traits. Results: The studied Pekin ducks of different genotype showed significant differences in body weight, carcass weight, dressing percentage, as well as percentages of breast muscles, skin with subcutaneous fat, abdominal fat, neck, and remainders of eviscerated carcass with neck. Duck genotype influenced the content of crude protein, crude fat, Na, K, P, Zn, $pH_{24}$, electric conductivity ($EC_{24}$), cooking loss, $L^{\star}$, $a^{\star}$, most textural traits of breast muscle, and also Na, Mg and Fe content, $EC_{24}$, drip loss, cooking loss and $L^{\star}$, $a^{\star}$, and $b^{\star}$ colour coordinates of leg muscles. Regardless of genetic origin, males exhibited higher BW, carcass weight and carcass neck percentage, as well as lower redness, hardness, chewiness and gumminess of breast muscle compared to females. The genotype${\times}$sex interaction was significant for the crude fat content and cooking loss of breast muscle, and for the yellowness of leg muscle. Conclusion: Star 53 HY ducks are more suited for broiler production due to their higher body weight and dressing percentage. Their breast and leg meat are characterized by more beneficial chemical composition but has poorer sensory and textural properties compared to the meat of P33 ducks.

• Korean Journal of Poultry Science
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• v.25 no.3
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• pp.147-155
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• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.912-916
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• 2008

Pre-slaughter conditions affect poultry meat quality. Therefore, stresses before slaughter like heat stress, struggle and shackling on the shackle line, crating and transport and feed withdrawal are very important for the poultry industry in respect of quality as well as welfare of the birds. However, exposure to heat in oxidative stress can in turn lead to cytotoxicity in meat type birds. Chickens exposed to heat stress before slaughter showed the lowest ultimate pH and birds shackled for a longer time the highest. The abdominal fat content was higher in heat stressed birds. Struggling on the shackle line hastened the initial rate of the pH drop and increased the redness of breast meat. Again, with increasing struggling activity, lactate concentration in breast muscle of chicken increased. Paler meat was found in birds that were transported for a longer time than in those after a small journey or not transported. The pre-slaughter and eviscerated weights were decreased as the length of feed withdrawal period increased.

• Korean Journal of Poultry Science
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• v.21 no.2
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• pp.113-117
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• 1994

Of the 200, 000 known species of molds, only 50 or 60 are known to be harmful to humans or livestock. Certain fungi that grow on grains and grasses can produce chemical substances called mycotoxins that adversely affect performance in poultry. There are several methods of preserving feed ingredients. The list includes: drying, antioxidants, mold inhibitors, organic acids, phosphates, cooking or toasting, fat extraction, blending and fermenting. Mold inhibitors are manufactured to inhibit mold growth and prevent the production of toxic substances. They are fungistats and not fungicides, that is, they only stop the growth of molds. Practical and cost-effective methods to detoxify mycotoxin containing feedstuffs are in great demand. 0.5% hydrated sodium calcium aluminosilicate added to the diet protected chicks from the deleterious effects of aflatoxin-contaminated feed. The dietary addition of antioxidants and methionine also significantly diminished the negative effects on body weight in chicks toxicated with 3.0 ppm aflatoxin B1.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.1038-1047
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• 2008

This study aimed at targeting fixed increases in body weight (100 g/wk) by quantitatively regulating energy allowances (ME) in broiler breeders from 5 to 20 wks of age. Four energy regimes were tested: 1. The energy required for maintenance, activity and growth was calculated for 100 g increases in body weight/wk and a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) was offered to the control group (ME-100) to achieve the anticipated weight gain. The energy allowances increased with age from 132 to 294 kcal/d. 2. Additionally, three energy regimes were considered, quantitatively reducing ME by 10% (ME-90) or 20% (ME-80) and increasing by10% (ME-110) over the control group. Each test group had 23 replicates5 female chicks housed in cages. The influence of energy regimes and age on growth, nutrient digestibility, carcass attributes, bone parameters and stress was evaluated at 4 wk intervals. Quantitative ME restriction by 10% (119-265 kcal/d) produced an average weight gain of 98.1 g/wk, which was closer to the targeted increase of 100 g/wk, whereas the control group attained it nine days earlier. Restriction of energy by 10 or 20% produced better conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P than 10% excess ME. Energy regimes did not influence eviscerated meat yield, but higher energy allowances (ME-110) significantly increased abdominal fat pad and liver weights and decreased giblet weight, percent muscle protein and tibia ash. Relatively higher stress was recorded in ME-restricted groups, as reflected by wider heterophil and lymphocyte ratios and increased bursa weight. Early age (5-12 wk) significantly influenced bone mineralization, conversion efficiency of feed, energy and protein and apparent digestibility of protein, Ca and P, while later ages (13-20 wk) increased eviscerated meat yield, abdominal fat, tibia weight and muscle protein and reduced stress. Energy regime x age interactions were significant and are discussed. In conclusion, the synthetic broiler line used in our study responded positively to controlled energy feeding during the rearing period. Breeders offered 119-265 kcal/d, a reduction of 10% energy over the control group, were more effective in regulating grower performance than the latter. In addition to energy regimes, age intervals also exhibited significant influence on specific parameters during the grower phase.

• Korean Journal of Poultry Science
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• v.24 no.4
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• pp.185-191
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• 1997

In order to obtain the basic information needed to utilize poultry by-products as feed resources, the yielding ratio, chemical composition and nutrient bioavailability of 5 offal components such as autoclaved head, feet, viscera, blood and feathers were investigated. Yielding ratios of head, feet, viscera, blood and feathers were 2.93％ 4.78％, 10.98％, 3.91％ and 4.83％, respectively. The crude protein contents of feathers (86.71％) and blood (82.99％) were higher than those of viscera (64.67％), feet (58.76％) and head (49.51％) , Inversely, the crude fat contents of blood (6.96％) and feathers (2.96％) were lower than those of head (26.19％), viscera (23.96％) and feet (13.73％). The crude ash contents of feet (21.69％) and head (20.38％) were higher than those of other by-products (0.96∼8.62％). The macro-mineral contents of head and feet were higher than those of other components, and the iron content of blood was higher than the other by-products. The total amino acid contents of poultry by-products showed the same trend as the crude protein contents. In addition, the Iysine content of feathers was very low compared to its high protein content. The essential amino acid contents of feathers were poorer than those of other offal components. Among the 5 offal components, the feathers showed the poorest amino acid availabilities. The ME contents were highest in viscera, and head, blood, feathers and feet. in decreasing order.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.9
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• pp.1249-1255
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• 2011

This study examined the effect of CLA, flaxseed oil and fish oil and their combination forms on crude fat of liver and fatty acid profiles of liver, breast and thigh meat in broiler chicks. A total of 72, 1-day-old Cobb broilers were assigned to 6 groups, and fed an experimental diet supplemented with 5 different fat sources; conjugated linoleic acid (2% CLA), flaxseed oil (2% FXO), fish oil (2% FHO), CLA and flaxseed oil combination (1:1; 2% CXO), and CLA and fish oil combination (1:1; 2% CHO). Eight birds per treatment were processed, and liver, breast and thigh samples were investigated at 21 d of age. As a result of this study, most fatty acids of liver, breast and thigh meat were influenced by fat sources supplemented in the diet (p<0.05). CLA addition resulted in an increase of crude fat and saturated fatty acid (SFA) content but a concomitant decrease in n-3 to n-6 fatty acid ratio was observed in liver (p<0.05). Moreover, the same trends of SFA and n-3 to n-6 fatty acid ratio were also observed in breast and thigh meats of birds fed CLA alone. In the CXO-fed group or CHO-fed group, n-3 and n-3 to n-6 fatty acid ratio in both breast and thigh meat increased compared with CLA group, while SFA content decreased (p<0.05). FHO fed-groups had the lowest proportion of n-6 fatty acid in both breast and thigh meats compared to other fat source treatments (p<0.05). In conclusion, the increased levels of crude fat and SFA in liver and meats obtained by feeding CLA could be reduced by its combination with FXO or FHO. In addition, the combination of CLA and FXO or FHO fed to broiler chicks could increase the n-3 to n-6 fatty acid ratio of their meat along with the deposition of CLA.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.80-84
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• 2005

An experiment was conducted to study the performance, carcass traits, serum lipid profile and immune competence in commercial broilers (2 to 42 d of age) fed graded levels (25, 50, 75 and 100%) of finger millet (FM) (Elusine coracana) in place (w/w) of yellow maize (YM). Each diet was fed to eight replicates (five female Vencobb broilers/replicate) housed in stainless steel battery brooders. The estimated metabolizable energy content of FM was about 540 kcal less than the YM. FM contained more protein (10.42 vs. 9.05%) and fibre (9.52 vs. 2.24%) compared to YM. Body weight gain, ready to cook yield, relative weights of giblet, liver, intestine and length of intestine at 42 d of age was not affected due to replacing YM with FM. But, the feed efficiency decreased in broilers fed diets containing 75 and 100% FM in place of YM at both 21 and 42 d of age. The amount of fat deposited in abdominal area decreased and the relative weight of gizzard increased with increase in level of FM in the diet. The serum HDL cholesterol at 21 and 42 d of age and serum triglycerides at 42 d of age decreased with increase in level of FM in diet. The relative weight of spleen and antibody titers against sheep red blood cells (SRBC) at 5 d post inoculation (PI) decreased in broilers fed FM at 100% of YM. However, the relative weight of bursa, SRBC titers at 10 d PI, antibody titers against ND virus and mortality were not affected due to incorporation of FM in place of YM in diet. The fat content in thigh muscle and liver decreased, while the protein content in these tissues increased with increase in the level of FM in broiler diet. Based on the results, it may be concluded that YM can be replaced with FM up to 25% on weight basis without affecting weight gain, carcass yields and immunity in commercial broiler diet (up to 42 d of age). Further, inclusion of finger millet reduced the fat deposition in thigh muscle, liver and in abdominal area compared to those fed maize as the principal source of energy.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.529-533
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• 2003

The intake, dry matter (DM) digestibility, total mean retention time (TMRT) and weight changes were investigated in four fat tailed and four Dorper sheep fed on a maize stover crop residue. Animals were subjected to five dietary treatments, which were: 90, 135 and $180g\;DM/kgBW^{0.75}/day$ of chopped maize stover offered with urea, and in subsequent dietary treatments $180g\;DM/kgBW^{0.75}/day$ of stover supplemented with either dried bean husks or poultry manure. Although not statistically different (p>0.05) fat tailed sheep had higher maize stover intake than the Dorper sheep when expressed per metabolic body weight. The DM intake and digestibility increased significantly (p<0.001) in both sheep breeds when the maize stover offer levels were increased from 90 to $135g/kgBW^{0.75}/day$. Dorper sheep had significantly (p<0.001) higher DM digestibility and longer total mean retention times for both the liquid and solid matter than the fat-tailed sheep. Fat-tailed sheep gained 4.75 kg while Dorper sheep gained 3.75 kg over the entire experimental period. The weight change per dietary treatment was affected by the amount of maize stover and the type and amount of supplement consumed. The higher DM digestibility and longer total mean retention time in Dorper sheep shows that the breed has adapted to utilize the low quality roughage diets. An indigenous fat tailed, has the potential to ingest high volumes of fibrous feed and has higher voluntary intakes relative to its body size. The two sheep breeds are a valuable genetic resource in sub Saharan Africa that is characterized by long dry season with no readily available and affordable conventional feeds for small ruminants.

• Korean Journal of Poultry Science
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• v.27 no.2
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• pp.133-153
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• 2000

The egg's interior quality is one of the most important criteria for commercial producers and consumers. Internal quality is complex, including aesthetic factors such as taste, freshness, nutritional and processing values, and the genetic influences upon these upon these factors ranges from none to considerable. The rate of cholesterol synthesis in the hen is very high compared to other animals and humans. Genetic selection, diet drugs and other chemicals can alter cholesterol concentration in the plasma of laying hen, but attempts to manipulate the cholesterol concentration in the egg yolk are generally unsuccessful since the cholesterol can only be changed to a small extent. Factors which may affect the degree of pigmentation of the yolk include the type of xanthophyll and its concentration in the feed, the feed composition, and the health of the hen. Several feed ingredients interact with carotenoid pigment to improve or reduce their deposition rates in yolks. Egg weight is determined by genetics, body size prior to first egg housing density, environmental temperature, lighting program, total feed consumption, calcium, phosphorus, niacin, water, methionine, total sulfur amino acids, energy, linoleic acid, fat and protein levels. Eggs need to be promote levels. Eggs need to be promoted a versatile commodity and new processed egg items need to be developed. Organic eggs are laid by hens which were raised in chemical and drug frdd environments. There are still difficulties in producing these eggs due to the availability of organic poultry feeds and cost of organic grains.