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91.
Cultivar variation in the nutritional quality of triticale grain was examined with respect to apparent metabolisable energy (AME), ileal digestibility of dry matter (DM), nitrogen (N) and amino acids, and growth, in male broiler chickens. Eight triticale cultivars and two wheat cultivars were grown in an agronomic trial at a single experimental site to collect grain samples. Mean (±SD) AME was 13.54 (±0.64) MJ kg?1 DM, with a range of 12.57 to 14.25 MJ kg?1 DM. There were significant (P<0.05) differences between the grain cultivars in their DM, N and amino acid digestibility at the terminal ileum. Apparent lysine digestibility coefficients varied between 0.85 and 0.97. There was a significant (P<0.01) relationship between nutrient digestibility at the terminal ileum and acid-detergent fibre (ADF) in the cereal grains. Three triticale cultivars (Towan, Grow-quick and Ningadhu) had a lower N and lysine digestibility than the other triticales or wheat cultivars, but this was related to their higher ADF content. Trypsin inhibitor level in the cereal grain did not influence either nutrient digestibility or growth rate. Growth rate of broiler chickens from 1 to 21 days of age fed balanced diets which contained 50% cereal grain was significantly affected by cultivar. Birds fed one of the wheat cultivars (Warigal) had a higher (P<0.05) feed conversion ratio (g feed g?1 liveweight gain) than those birds fed diets containing triticale. Feeding birds diets which contained the triticale cultivar Ningadhu and the maize resulted in greater (P<0.05) liveweight gain than did the other cereal grains tested.  相似文献   
92.
93.
An experiment was conducted on broiler chickens to study the effects of different dietary fats (Conjugated linoleic acid (CLA), fish oil, soybean oil, or their mixtures, as well as palm oil, as a more saturated fat), with a as fed dose of 7% for single fat and 3.5 + 3.5% for the mixtures, on Peroxisome Proliferator-Activated Receptors (PPARs) gene expression and its relation with body fat deposits. The CLA used in this experiment was CLA LUTA60 which contained 60% CLA, so 7% and 3.5% dietary inclusions of CLA LUTA60 were equal to 4.2% and 2.1% CLA, respectively. Higher abdominal fat pad was found in broiler chickens fed with a diet containing palm oil compared to chickens in the other experimental groups (P ≤ 0.05). The diets containing CLA resulted in an increased fat deposition in the liver of broiler chickens (P ≤ 0.05). The only exception was related to the birds fed with diets containing palm oil or fish oil + soybean oil, where contents of liver fat were compared to the CLA + fish oil treatment. PPARγ gene in adipose tissue of chickens fed with palm oil diet was up-regulated compared to other treatments (P ≤ 0.001), whereas no significant differences were found in adipose PPARγ gene expression between chickens fed with diets containing CLA, fish oil, soybean oil or the mixture of these fats. On the other hand, the PPARα gene expression in liver tissue was up-regulated in response to the dietary fish oil inclusion and the differences were also significant for both fish oil and CLA + fish oil diets compared to the diets with palm oil, soybean oil or CLA as the only oil source (P ≤ 0.001). In conclusion, the results of present study showed that there was a relationship between the adipose PPARγ gene up-regulation and abdominal fat pad deposition for birds fed with palm oil diet, while no deference was detected in n-3 and n-6 fatty acids, as well as CLA on PPARγ down regulation in comparison to a more saturated fat. When used on its own, fish oil was found to be a more effective fat in up-regulating hepatic PPARα gene expression and this effect was related to a less fat deposition in liver tissue. A negative correlation coefficient (-0.3) between PPARα relative gene expression and liver tissue fat content confirm the anti-lipogenic effect of PPARα, however, the change in these parameters was not completely parallel.  相似文献   
94.
BACKGROUND: The experiment was conducted to determine the effects of dietary supplementation of oxidised oil with or without vitamin E on performance, nutrient digestibility, some blood traits, lipid peroxidation and antioxidant defence system of male broilers. RESULTS: The supplementation of oxidised oil with or without vitamin E to the grower diets did not significantly affect performance, the pH and viscosity values of excreta and nutrient digestibilities in male broilers. Oxidised oil supplementation slightly increased plasma triglyceride and cholesterol concentrations but did not alter plasma glucose concentration. Although malondialdehyde (MDA) and nitric oxide concentrations tended to be higher in the oxidised oil group, these increases were not significant. Birds fed the diet containing oxidised oil had significantly lower superoxide dismutase (SOD) activity. However, no differences were observed in glutathione peroxidase (GSH‐Px) activity and uric acid concentrations of broilers fed oxidised oil as compared to the control group. Dietary vitamin E supplementation decreased MDA concentration whereas increasing SOD activity, suggesting that vitamin E supplementation reduced susceptibility to lipid peroxidation. CONCLUSION: The results showed that a milder oxidative stress occurred by supplementation of moderately oxidised oil to the diet of broilers and vitamin E supplementation had been helpful in alleviating lipid peroxidation. Copyright © 2011 Society of Chemical Industry  相似文献   
95.
中药渣及添加剂用于肉仔鸡日粮的效果   总被引:3,自引:1,他引:3  
利用药厂生产“增长乐”取汁后的中药渣,配合于肉仔鸡日粮中并对其生长效果进行观察观察。肉仔鸡日粮中添加3%的中药渣并配合200mg/kg铜、1%预混添加剂。结果表明:添加3%的中药渣较对照组提高日增重8.2%;节省料5.7%;配合使用1%预混剂,则日增重提高19.6%,节省上料14.6%,节省料14.6%。总结的结果表明:中药渣及添加剂作为一种促生长剂应用于肉仔鸡日粮中是可行的。  相似文献   
96.
The effects of flaxseed (FS) processing and inclusion levels on broiler performance and fatty acid deposition were examined. FS was provided as whole seed, ground or pellet‐then‐mashed at a dietary level of 0, 12 or 14% during days 1 to 21. These levels represented control, threshold and over‐threshold, respectively. During days 22 to 40, the threshold level was increased to 15%, while the over‐threshold level increased to 17%. After 21 days of feeding, the performance of birds fed a diet with 12% pellet‐then‐mashed FS were comparable (p > 0.05) with those fed mashed control diet, but superior to those fed a diet of whole FS (p < 0.05). There was interaction (p < 0.05) between diet processing and FS level on weight gain, with pellet‐then‐mash processing being more effective at the 12% FS inclusion level than at the 14% level in improving performance. The beneficial processing effect on performance diminished during days 22 to 40. Furthermore, carcass cut‐up percentage was not affected (p > 0.05) by the treatments, except that increased FS level resulted in smaller fat‐pad and larger liver (p < 0.05). Birds deposited omega‐3 (n‐3) fatty acids in breast and thigh muscle the most with higher FS inclusion and pellet‐then‐mash processing. On day 40, the total n‐3 fatty acids made up 22.1 and 24.4% in the muscle lipids of breast and thigh samples from birds fed pellet‐then‐mashed FS at the level of 12% during days 1 to 21 and at the level of 15% during days 22 to 40, respectively. These values were higher (p < 0.05) than those found in birds fed diets of similar FS levels but as whole seed or ground seed. Up to 12% pellet‐processed FS can be incorporated into broiler diets with satisfactory growth, while maximizing n‐3 fatty acid deposition in the tissues. Copyright © 2005 Society of Chemical Industry  相似文献   
97.
甜菜碱在肉鸡体内供甲基代谢及其节约蛋氨酸效应机制   总被引:1,自引:0,他引:1  
选用 4 5 0羽 2 2日龄艾维茵肉鸡 ,按饲养试验要求分成 3组 (每组 3个重复 ) ,分别设为不添加蛋氨酸的对照组和添加 10 0 0mg/kg蛋氨酸的对照组 ,另一组则为添加 5 0 0mg/kg甜菜碱的试验组 ,进行了为期 2 1d的饲养试验。结果表明 :与不添加蛋氨酸组比 ,添加甜菜碱显著提高了肉鸡的日增重 (P <0 .0 5 ) ,降低了料重比(P <0 .0 5 ) ,达到了添加蛋氨酸的效果 (P >0 .0 5 ) ;添加甜菜碱导致了试验鸡肝脏甜菜碱 -高半胱氨酸S -甲基转移酶 (BHMT)活性升高 ,BHMT活性比不添加蛋氨酸组和添加蛋氨酸组均显著增高 (P <0 .0 1) ;与不添加蛋氨酸组比 ,添加甜菜碱还使肝脏甲基化反应产物 (游离肉碱和肌酸 )的生成量明显增多 (P <0 .0 1)和胸肌中两者的存储量显著增加 (P <0 .0 1) ,但与添加蛋氨酸组比无明显差异 (P >0 .0 5 )。上述结果提示 :甜菜碱在肝脏BHMT调控下 ,替代蛋氨酸为机体甲基化产物的合成提供甲基 ,从而产生节约蛋氨酸的效应。  相似文献   
98.
Research was completed to investigate the impact of dietary rapeseed meal (RSM) sinapine (SNP) on broiler chickens. The control treatment was based on a corn/soybean meal diet, as were six additional treatments which contained three levels of SNP bisulphate or semi‐purified SNP in the form of an ethanol extract concentrate. The last three treatments were corn‐based but soybean meal was replaced by graded levels of RSM at 15, 22.5 and 30% of the diet and thereby added SNP in its native form. SNP bisulphate and SNP ethanol extract did not affect feed intake and performance of broiler chickens. SNP bisulphate increased diet AME (apparent metabolisable energy) (P < 0.01) while SNP ethanol extract increased diet AME and faecal protein digestibility (P < 0.01 and 0.05 respectively) in comparison with the control diet. Dietary treatment caused minor effects on tissue measurements. All the diets containing SNP reduced the empty weight of caeca (P < 0.05 or 0.01), suggesting that the hind gut might be an important metabolic site for SNP. The ileal digestibility of SNP was 35–42, 27–38 and 30–46% for SNP bisulphate, SNP ethanol extract and RSM SNP respectively, while faecal digestibility values were 68–72, 65–75 and 54–63% for the same treatment groups. A major metabolic pathway of SNP via hydrolysis into sinapic acid and choline in the digestive tract was identified. Copyright © 2003 Society of Chemical Industry  相似文献   
99.
A total of 360 one‐day‐old broilers (Ross 308) were allocated to three treatment groups with four replicates each of 30 chicks to evaluate the effects of the dietary hazelnut kernel oil (HKO) inclusion on the performance and the composition of fatty acid of meat in broilers. Treatments were diets with (1) soybean oil (SO), (2) HKO, or (3) HKO + SO (in equal amount, HKSO) added to the basal diets. There were no significant differences in weight gain, feed per gain, dressing percentage, abdominal fat weight, and mortality among the different dietary oil sources. Dietary HKO decreased (P < 0.01) linoleic and linolenic acids contents and the ratio of SFA:MUFA (saturated fatty acids:unsaturated fatty acids) of breast meats in broiler, and increased oleic acid content compared to SO. The result indicates that meat from broiler chickens fed diets containing HKO, singly or combined with SO could be an important source of oleic acid for human diets. Copyright © 2007 Society of Chemical Industry  相似文献   
100.
The influence of dietary oil type (OT) and late feed restriction (FR) on growth, caeca bacteria count, carcass, separable fat depots, serum and muscle lipids, and meat quality in broilers is examined. In total, 224, 21-day-old female Arbor acres broilers are randomly allotted to either PN, Unrestricted+50 g kg−1 palm oil (PO); PR, 25%-FR+PO; SN, Unrestricted+50 g kg−1 soybean oil (SO); or SR, 25%-FR+SO for 21 d. The SN and PR birds have the heaviest and lightest body weight gain (BWG), respectively. Feed conversion ratio (FCR) is poorer in the PN birds. Feed-restricted birds have more caeca Lactobacillus and lower Salmonella, serum cholesterol, and triglycerides. Carcass yield is higher in SR birds and lower in PN birds. The FR-OT interaction is significant for muscle lipids and weight of fat depots. The PN birds deposit more abdominal, intramuscular, sartorial, mesentery and neck fats, muscle saturated fatty acids, and C18:1n-9 and lower C18:3n-3 and C20:5n-3 than other birds. Neither OT nor FR affects the pH, color, water holding capacity, and oxidative stability of breast meat. The changes elicited by 25%-FR on BWG, FCR, carcass yield, depot fats, and muscle lipids in female broilers are dependent on dietary OT. Practical Application: Fast growth rate and unrestricted access to feed can predispose broiler chickens to excessive fat accretion, which is counterproductive. Producing high-quality carcasses that meet consumers’ expectation is crucial for sustainable and efficient broiler production. The possible interaction between dietary OT and late quantitative FR in mitigating excessive fat accretion and altering production indices in female broilers is explored. Late quantitative FR reduces BWG, FCR, serum lipids, caeca pH and Salmonella spp. and fat accretion in fat depots, and enhances carcass yield and caeca Lactobacillus spp. However, the impacts are more pronounced in the PO birds than the SO birds. Late FR improves the C18:3n-3 and C18:2n-6 contents in PO meat while reducing the C14:0 and C16:0 contents in SO meat. These findings explicate that dietary OT and late quantitative FR can be synergistically used to mitigate excessive fat accretion and alter growth, caeca microflora, and muscle lipids in broilers.  相似文献   
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