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1.
1. Growing chickens decrease their voluntary food intake when they receive a diet deficient in a single essential amino acid. Our previous studies suggest that the decreased food intake was associated with some metabolic changes. 2. In order to reveal the involvement of plasma lysine fluctuations in the reduction of food intake, we examined whether maintaining the plasma lysine concentration in chickens on a lysine-free diet (the purified diet contained no lysine) restored the food intake to that of the control (lysine hydrochloride 11.9 g/kg) group. 3. Male egg-type chickens at 21 d of age were injected with lysine at doses of 0.1 g/ml one hour after presenting the lysine-free diet. This injection increased the plasma lysine concentration one hour later and kept it similar to that of the control group for the following 2 h. Chickens ate the lysine-free diet as much as the control diet when their plasma lysine concentration was kept at a similar level to the control group. Injection of saline or alanine (0.12 g, isonitrogenous to lysine 0.1 g) into the crop of chickens on the lysine-free diet did not bring about the variations of food intake and plasma lysine concentrations as observed in those with lysine. 4. These findings show that the food intake variation was attributed to the plasma lysine concentration in the chickens on the lysine-free diet. 相似文献
2.
1. The effect of caecal ligation and colostomy on water intake and excretion were examined in chickens fed a low-protein diet or a low-protein diet supplemented with urea. 2. When fed a low-protein diet, the water intake and the ratio of water intake to food intake were increased by colostomy (P < 0.05) but not changed further by caecal ligation of colostomised chickens. 3. When fed a low-protein diet supplemented with urea, the amount of water intake and the ratio of water intake to food intake were not changed by either treatment. 4. Total water excretion was much higher in the colostomised plus caeca-ligated chickens than in other 3 groups fed both types of diet (P < 0.05). 5. The amount of faecal water excretion was increased by cecal ligation in colostomised chickens fed either diet (P < 0.01). 6. No effect of any treatment on water balance was observed in chickens fed either diet. 7. It is concluded that the lower intestine plays a useful role in the water economy of chickens fed a low-protein diet or a low-protein diet supplemented with urea. 相似文献
3.
1. An experiment was conducted with 98 male and 98 female broiler chickens (Ross 308) to study the effect of growth rate, induced by different dietary means, sex and live weight (1500?g and 2000?g) at slaughter on production parameters, bone strength and sensorial characteristics of the breast meat. 2. The birds were divided into four groups and individually fed a standard commercial diet, a high energy diet or low energy diet from d?11 to slaughter at between d 28 and 39. Three groups were fed ad libitum and a further group was fed a restricted amount of the high energy feed. Half of the birds in each group were slaughtered at approximately 1500?g and the other half at 2000?g live weight. 3. The diets resulted in different growth rates. The chickens fed the high energy and the commercial diet had the highest growth rate at both live weights at slaughter. The restricted fed chickens had lower bone strength than the chickens fed the low energy diet. 4. Breast meat from male broilers was juicer, more tender and less hard than breast meat from females. Chickens slaughtered at 2000?g live weight were juicer than those slaughtered at 1500?g. Chickens given the high energy feed ad libitum and restricted had different growth rates, but the sensory parameter related to texture showed no difference. 5. It was concluded that an increased slaughter weight might improve meat quality due to improved juiciness. 相似文献
4.
1. Two experiments were carried out to determine the response of broiler chicks to threonine‐supplemented diets between 10 and 28 d and 7 and 21 d of age, respectively. 2. In the first experiment female broiler chicks were fed on 11 experimental diets. Two iso‐energetic basal diets (diets 1 and 2) were prepared with 200 and 160 g CP/kg and 7·6 and 6·0 g threonine/kg respectively. Both diets contained 11·5 g lysine and 8·7 g sulphur‐containing amino acids/kg. Diet 3 was composed of diet 2, supplemented with all essential and non‐essential amino acids (EAA and NEAA, respectively) except threonine, to the concentrations of the amino acids in diet 1. The NEAA were added as a combination of glutamic acid and glycine. Diets 4 to 11 had the same compositions as diet 3, but contained increasing amounts of threonine. 3. For birds fed on diet 2, gain was significantly lower and food/gain ratio was significantly higher than for birds fed on diet 1. Supplementation with EAA, NEAA and threonine to the same concentrations in diet 1 resulted in a performance similar to that found on diet 1. 4. In experiment 2, male and female broiler chicks both received 10 experimental diets. Diet 1 contained 220 g CP/kg and 8.5 g threonine/kg, diet 2 contained 160 g CP/kg from natural raw materials and 6 g threonine/kg. Both diets contained 12·4 g lysine and 9·3 g sulphur‐containing amino acids/kg. Basal diet 2 was supplemented with all EAA and NEAA to the concentrations of basal diet 1, except for threonine. Diets 3 to 10 had the same compositions as the supplemented diet 2, but contained increasing amounts of threonine. 5. For male and female chicks on diet 2, gain was significantly lower and food/gain ratio significantly higher than those on diet 1. Diet 10 (160 g CP/kg plus all EAA, including threonine, and NEAA supplemented to the concentrations of diet 1) resulted in the same performance as diet 1. 6. The results indicate that, when low protein maize‐soyabean meal diets supplemented with EAA and NEAA with 13·31 MJ ME/kg were fed to male and female broiler chicks until 21 d of age, improvements in gain and food/gain ratio were obtained when the dietary threonine content was increased to 7·25 g/kg. When female chicks were fed threonine‐supplemented diets to 28 d of age, improvement in gain and food/gain ratio was obtained when the threonine concentrations were increased to 6·32 g/kg diet. 7. Curves have been fitted to the data, from which a cost‐benefit analyses can be made and an optimum threonine dose calculated, using local prices. 相似文献
5.
本试验选择24头健康PIC断奶仔公猪,单笼饲养,随机分为4个处理:对照组,氧化应激组,氧化应激组+0.8%精氨酸,1.6%精氨酸+氧化应激组。在试验第8天,各试验组仔猪腹腔注射敌草快诱导氧化应激,对照组仔猪注射等量生理盐水。在应激前(0 h),应激后6、24、48 h和96 h前腔静脉采血分离血浆。结果表明:氧化应激显著降低仔猪日增重、日均采食量及饲料转化效率。在氧化应激状态下,补充1.6%Arg显著增加仔猪的日均采食量。氧化应激降低仔猪血浆精氨酸、谷氨酸、赖氨酸、蛋氨酸、苏氨酸的浓度,显著增加血浆异亮氨酸和缬氨酸的浓度。在氧化应激条件下,补充精氨酸能显著提高血浆精氨酸、赖氨酸、异亮氨酸的浓度,显著降低血浆蛋氨酸、谷氨酸、缬氨酸的浓度。 相似文献
6.
1. Growth rates and carcase characteristics were measured in male broiler chickens fed on a control diet deficient in methionine ( c. 2·8 g/kg methionine) or a series of diets containing graded levels of betaine or DL-methionine or both additives. 2. We aimed to answer 2 main questions. First, can betaine replace part of the methionine in a broiler ration? Secondly, is there a synergism between methionine and betaine? 3. Birds given the control diet or that supplemented only with betaine ate less, grew more slowly, had higher food convension ratio (FCR) and varied more in mass at 42 d than birds fed diets with DL-methionine. Adding 1·2 g/kg DL-methionine to the control ration produced the heaviest birds at 42 d (2500 g) with the 2nd heaviest breast muscle (366 g). 4. After correcting for treatment differences in body mass (analysis of convariance), birds fed on the control diet and the diet supplemented with betaine only, had relatively lighter breast muscles but relatively heavier abdominal fat pads than those of birds given diets supplemented with DL-methionine. However, adding betaine to diets containing added methionine further improved the relative breast muscle yield. 5. After correcting for differences in body mass between treatments, birds fed on diets containing most methionine had lighter viscera than birds fed diets deficient in methionine. This demonstrated gut plasticity, suggesting that the viscera enlarged to sequester methionine from low-methionine diets. 6. Our data refute the hypothesis that betaine can substitute for methionine in broilers fed diets that are marginally deficient in methionine plus cystine. However, betaine may improve carcase composition, especially breast meat yield. 相似文献
7.
1. The study was part of a project designed to investigate if organic selenium (Se) can ameliorate the toxic effects of cadmium (Cd). The main objective of the present study was to investigate, in the chicken, the interactions between Se, Cd and the following elements: Sb, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Mo, Ni, V and Zn. 2. A total of 300 1-d-old chickens (broilers) were randomly distributed among 4 dietary treatments with 5 replicate pens per treatment. In T1, chickens were fed on a diet with 0·3?mg/kg added Se, without added Cd. In T2, chickens were fed on a diet with 0·3?mg/kg Se and 10?mg/kg Cd. In T3, chickens were fed on a diet with 0·3?mg/kg Se and 100?mg/kg of Cd added and in T4 treatment, chickens were fed on a diet with 3?mg/kg Se and 100?mg/kg Cd added. Se was added as Se-yeast. Cd was added as cadmium chloride (CdCl 2). On d 28 and 42, two chickens per replicate pen were killed for collection of whole blood, liver, kidney and breast muscle samples. Samples were analysed by ICP-MS. The data were analysed using a multivariate linear model. 3. While low Cd concentrations in the diet led only to an increase of Cd concentration in the examined tissues, addition of high concentrations of Cd increased the concentration of Cd, Cu, Sb and V and decreased that of Se, Mn and Fe. Addition of high Se concentrations did not significantly reduce Cd concentration. 4. Prior to model application, correlations of 78 elements were noted, while after model application 39 correlations were noted. Most notably, Cd was correlated with Ca, Co, Cu and Mg, while Se was correlated with Mn. 5. The present study revealed several correlations between essential, probably essential and toxic elements illustrating the importance of the balance between pro-oxidants and antioxidants. 相似文献
8.
1. The effect of dietary chitosan on fat deposition and lipase activity in the small intestinal contents was investigated in broiler chickens fed an adequate or high metabolisable energy (ME) diet. 2. Male broiler chickens at 14 d old were fed on the adequate or high ME diet supplemented with 0 or 50 g/kg chitosan, which has a low viscosity, for 3 weeks. 3. Dietary chitosan did not affect food intake, body weight gain or food efficiency in either dietary ME groups. 4. Dietary chitosan reduced the excessive abdominal fat deposition induced by the high ME diet. 5. Dietary chitosan increased the weight of intestinal contents irrespective of dietary ME concentration. 6. Dietary chitosan decreased the lipase activity per g of small intestinal contents. 7. These results suggest that dietary chitosan with low viscosity decreases lipase activity and fat absorption in the small intestine, consequently resulting in a reduction of fat deposition in broiler chickens. 8. It was concluded that dietary chitosan with low viscosity can decrease body fat deposition without reducing food intake and body weight gain in broiler chickens. 相似文献
9.
本试验旨在研究日粮中添加不同水平腐植酸钠对肉仔鸡成活率及生长性能的影响。选用1000只健康科宝商品肉仔鸡,随机分为5组,每组5个重复,每个重复40只鸡。对照组饲喂基础日粮,Ⅰ～Ⅳ组在基础日粮中分别添加黄霉素、1.0%腐植酸钠、2.0%腐植酸钠、1.0%腐植酸钠＋黄霉素。试验期49 d。结果表明,与对照组相比,各组肉仔鸡成活率均有明显提高,Ⅲ组平均日采食量显著提高（P＜0.05）,Ⅱ、Ⅳ组平均日增重显著提高（P＜0.05）,Ⅱ、Ⅲ、Ⅳ组料重比显著降低（P＜0.05）。综上所述,日粮中添加腐植酸钠可提高肉仔鸡的成活率,改善其生长性能,其中以添加1.0%腐植酸钠效果最佳,同时与黄霉素具有较好的配伍作用。 相似文献
10.
1. The objective of this experiment was to study the influences of xylanase and citric acid on the performance, nutrient digestibility, digesta viscosity, duodenal histology, and gut microflora of broilers fed on a wheat based diet. 2. The experiment was carried out as a 2?×?3 factorial arrangement with two concentrations of xylanase (0 and 200?mg/kg) and three concentrations of citric acid (0, 20 and 40?g/kg). A total of 408 one-day-old chickens with similar body weight were distributed into 24 pens with 17 birds/pen. Each dietary treatment was given to 4 replicate pens from 0 to 24?d of age. To determine the apparent nutrient digestibility, chromic oxide (3?g/kg) was added to the diets as an indigestible marker. 3. Xylanase significantly increased body weight gain at 24?d of age by 1·4% and improved gain-to-feed (G:F) by 3·6%. The inclusion of 40?g/kg citric acid decreased feed intake and body weight gain by 15·4% and 11·8%, respectively. The inclusion of 20?g/kg of citric acid decreased feed intake, but it did not affect body weight gain of broilers at 24?d of age. The inclusion of 20 and 40?g/kg citric acid improved G:F by 3·8 and 4·3% respectively. Xylanase significantly decreased the viscosity of digesta and improved retention of DM, CP, and energy. 4. Xylanase and citric acid did not have any effect on the histo-morphology of the duodenum and intestinal microbial population. 5. In conclusion, citric acid at 20?g/kg decreased feed intake, did not have a negative effect on body weight gain, and improved G:F. Xylanase decreased digesta viscosity, increased nutrient retention and consequently improved performance of broilers fed on a wheat based diet. 相似文献
11.
1. A study was conducted to investigate the effectiveness of high dietary copper concentrations obtained from tribasic copper chloride (TBCC, 58% copper) and copper sulphate pentahydrate (CuSO 4, 25% copper) in replacing antibiotic growth promoters (AGP) in duck diets. 2. A total of 960 one-day-old Cherry Valley meat-strain ducks were divided into 3 treatment groups, with 8 replicates per treatment, in a 6-week feeding trial. The ducks were fed a basal diet supplemented with AGP (40?mg zinc bacitracin/kg and 40?mg garlicin/kg of diet) or 150?mg of Cu/kg of diet, given as either CuSO 4 or TBCC. 3. The body weight, average daily gain, average daily feed intake and mortality of ducks were not affected by the dietary treatments. However, the feed/gain ratio of ducks that were fed TBCC diets was significantly lower than those of ducks that were fed CuSO 4 diets and were similar to those in the AGP group. 4. TBCC increased the Cu content in the liver tissue of ducks compared with the content in those that were fed the diet supplemented with AGP. TBCC also increased the Fe and Zn content in breast muscles compared with that in ducks that were fed the diet supplemented with CuSO 4. 5. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were significantly higher in the serum of ducks that received the diet supplemented with TBCC than AGP or CuSO 4. TBCC treatment decreased the malondialdehyde (MDA) content in serum of ducks compared with groups supplemented with CuSO 4. 6. No significant difference was observed in liver or muscle fat content among the different dietary treatment groups. The serum low-density lipoprotein cholesterol concentration was lower in ducks fed AGP diets than those fed CuSO 4 diets. 7. It was concluded that the replacement of AGP with 150?mg of Cu/kg of feed from TBCC improved the feed efficiency, trace mineral deposition and antioxidant status more than when the source of copper was CuSO 4. 相似文献
12.
1. Two experiments were conducted to determine the effects of dietary nucleotide supplementation on broiler performance, and physical and morphological development of the gastrointestinal tract. 2. Experiment 1: A total of 180 one-d-old male chicks were placed in battery brooders in 3?×?6 replicate pens containing 10 chicks each. Chicks were randomly assigned to one of the three dietary treatments; a maize-soyabean meal based diet supplemented with 0, 0·25, and 0·50% Torula yeast RNA (as a source of nucleotides) from 0 to 16?d of age. 3. Experiment 2: A total of 1344 one-d-old male chicks were placed in floor pens and reared on recycled wood shavings (two flocks) under a high stocking density (0·068?m 2/bird). Chicks were randomly assigned to one of the 4 dietary treatments (0, 0·25% Torula yeast RNA, 2% and 6% Nupro®) for the starter period (0 to 14?d of age) with 6 replicate pens containing 56 chicks each. All the birds were fed on the same common grower diet with no supplementation of nucleotides from 15 to 32?d of age. 4. Experiment 1: Supplementing the diets with up to 0·50% Torula yeast RNA did not affect broiler performance, or relative intestinal tract weight and length of broilers at any periods measured. 5. Experiment 2: From 0 to 14?d of age, broilers fed on the diets supplemented with 0·25% Torula yeast RNA and 2 and 6% Nupro® were significantly heavier and had improved feed conversion (feed:gain) ratios as compared with the birds fed on the control diet. Supplementing the starter diet only with 2% Nupro® supplementation significantly improved body weight (BW) gain as compared with the control diet over the entire experiment (0 to 32?d of age). Broilers fed on the diets supplemented with 2 and 6% Nupro® from 0 to 14?d of age had better feed conversion (feed:gain) ratios over the entire experiment (0 to 32?d of age) as compared with the birds fed on the control diet, even though the birds were only fed on the diets supplemented with Nupro® from 0 to 14?d of age. The broilers fed on the diets supplemented with 0·25% Torula yeast RNA and 2% Nupro® had higher villus height and an improved villus height-to-crypt depth ratio as compared with birds fed on the control or 6% Nupro® diet at 14?d of age. 6. It is generally assumed that nucleotides are not an essential nutrient; thus there is no need to supplement the diets of broilers reared under normal conditions. However, dietary nucleotide supplementation may be important to maintain maximum growth performance when birds are exposed to stress conditions, such as high stocking density combined with dirty litter. 相似文献
13.
1. Rice bran lysolecithin (RBL) was evaluated in broiler chicken diets. In the first experiment, RBL was included in diet at 0, 0·5, 2, 8 and 32?g/kg and fed to 250 broiler chickens from 0 to 42?d of age. In the second experiment, RBL was fed at 0, 25 and 50?g/kg diet to 405?day-old broiler chickens until 21?d of age, while during the finisher phase (22–35?d of age) chickens receiving each concentration of RBL were given all three concentrations of RBL in a 3?×?3 factorial manner. The diets were isocaloric. 2. Body weight, food consumption and food conversion efficiency were unaffected by feeding RBL, while the weight of pancreas increased at ≥2?g/kg of RBL in diet (experiment 1). In experiment 2, body weight was greater in the chickens receiving RBL at either 25 or 50?g/kg (21?d) and 50?g/kg (35?d of age). At 21?d of age, food consumption was greater at 25 or 50?g RBL/kg diet, while food conversion efficiency improved with 50?g RBL/kg diet. 3. Fat digestibility increased with RBL at 32?g/kg (experiment 1) and ≤25?g/kg (experiment 2). Rice bran lysolecithin increased ready to cook weight at 50?g/kg during starter phase and decreased abdominal fat at 25 and 50?g/kg during finisher phase (experiment 2). Liver and meat fat content were not affected. 4. It is concluded that lysolecithin from rice bran oil could be used as energy supplement in broiler chicken diet. 相似文献
14.
1. Three experiments were performed to study the effects of amino acid imbalance on the growth of genetically lean (LL) or fat (FL) male chickens from 28 to 42 d of age. In experiment 1, five concentrations of digestible lysine were compared (4.75, 6.75, 7.75, 8.75 and 9.75 g/kg). In experiment 2, four concentrations of digestible arginine were compared (6.53, 7.69, 8.84 and 10.0 g/kg). In experiment 3, three diets were compared: a high‐protein diet (189 g CP/kg), a low‐protein diet containing added essential amino acids (EAA) (144 g CP/kg) and this low‐protein diet supplemented with 40 g/kg of non‐essential amino acids (NEAA) (glutamic acid + aspartic acid). 2. LL birds exhibited a lower growth rate than the FL when the diet was deficient in either lysine or arginine. Plotting weight gain against lysine or arginine intake suggested that most of this effect was caused by variations in food intake. 3. When protein gains (body or total proteins) were plotted against lysine or arginine intake, LL chickens appeared more efficient than FL chickens. 4. Similar growth rates, although slightly lower in FL, were obtained with low‐ and high‐protein diets. However, NEAA supplementation of the low‐protein diet reduced adiposity of LL and did not modify that of FL. Increasing crude protein content (all amino acids) was more effective than NEAA supplementation in decreasing the adiposity of both lines. 相似文献
15.
1. Two experiments were conducted to compare food intake responses of broiler chicks fed diets varying in lysine, methionine, and tryptophan. Diet D was formulated to create simultaneous deficiencies of lysine, methionine, and tryptophan. Diet A matched National Research Council (1984) recommendations for broilers, and diets B and C were, respectively, 2:1 and 1:2 mixes of diets A and D. 2. Short‐term food intake can provide information on the sequences of adaptation of chicks to a diet deficient in essential amino acids. 3. Chicks consumed 26% less of diet D than A during the first 24 h posthatch. When chicks fed diet A or D to 7 d of age were then fed one of 4 diets singly, within 24 h intake was lowest for chicks fed diet D. Within 48 h, food intake of diet C was more than that of diet D and less than that of diet A, while for diet B intake was more than of diet D but not different from diet A. 4. In the second experiment, chicks were fed diet A to 8 d and then diets A or D alone or given a choice of diets A and D from 8 to 20 d of age. Within 4 to 8 h, food intake of chicks fed diet D alone decreased markedly followed by partial recovery within 24 h. In a choice setting, consistent preference of Diet A over Diet D was observed within 7 h followed by stabilisation at about 65% diet A to 35% diet D. 5. Chicks fed diet D alone from 8 to 20 d of age, then placed in the same choice situation preferred diet A to D with a delay of less than one h and stabilisation at about 85%. Chicks provided a choice of diets A and D from 8 to 20 d, and then diet D alone reduced their food intake more quickly than those not given a choice initially. 6. Broiler chicks appear to react to amino acid deficiencies within a short period (hours) by adjusting their feed intake and/or selection. The response is influenced by age and prior experience. 相似文献
16.
本试验旨在研究霉变饲料和／或添加复方霉菌毒素吸附剂对肉鸡人工感染发生的影响。选取140羽1日龄健康的AA肉鸡随机分成7个组．每组4个重复。第1组为空白对照组,饲喂基础日粮;第2组饲喂霉变饲料;第3～7组以混合感染病鸡病变组织匀浆饮水制作人工感染疾病模型;第3～7组分别饲喂基础日粮、霉变饲料、霉变饲料＋复方霉菌毒素吸附剂、霉变饲料＋复方霉菌毒素吸附剂＋抗氧化剂、霉变饲料＋复方霉菌毒素吸附剂＋抗氧化剂＋中药增免剂。试验期35d。结果发现,肉鸡摄入霉变饲料与摄入正常饲料相比,提高肉鸡料重比和死淘率,显著降低肉鸡增重、胸腺指数、法氏囊指数,显著降低血清IBDV、H9N1v和NDV抗体水平（P〈0．05）。给人工感染肉鸡饲喂霉变饲料与饲喂正常饲料相比．显著提高料重比和死淘率,显著降低肉鸡增重、胸腺指数和脾脏指数,显著降低血清IFN-1、IL-2、IL-4和IL-12含量以及LTR,显著降低血清IBDV、H9N1V和NDV抗体水平（P〈0．05）。霉变饲料中添加复方霉菌毒素吸附剂能显著提高混合感染肉鸡增重,并降低料重比和死淘率（P〈0．05）,显著提高胸腺指数、法氏囊指数（P〈0．05）,显著提高血清IBDV、H9N1V和NDV抗体水平（P〈0．05）。可见,霉变饲料可导致肉鸡免疫功能抑制,加重肉鸡混合感染病情;复方霉菌毒素吸附剂能有效缓解霉变饲料对人工感染肉鸡生产性能、免疫功能和病情的不利影响,抗氧化剂和免疫功能增强剂可减轻霉变饲料的毒性作用。 相似文献
17.
1. Fermented plant product (FPP) is a natural fermented food which is produced from a mixture of fermented fruit and vegetables, and rice bran (1:9). 2. To investigate the effects of FPP on growth performance, some blood variables, carcase characteristics and intestinal histology were determined in 192 broilers. They were divided into 4 groups, with 4 replicates of 12 chicks each; the chicks were provided ad libitum access to a diet consisting of 0, 0·5, 2·0 and 4·0% dietary FPP. 3. The crude protein and metabolisable energy concentrations of these diets were adjusted to 230?g CP/kg and 13·40?MJ ME/kg for the 7 to 21?d old chicks, and 200?g CP/kg and 13·40?MJ ME/kg for the 22 to 49?d old chicks, respectively. 4. At 49?d of age, feed intake, body weight gain and feed efficiency tended to increase with increase in FPP concentrations. Feed intake increased in the 4·0% dietary FPP group, BW gain increased in the 2·0% and 4·0% dietary FPP groups and feed efficiency increased in all experimental groups. 5. There were no differences among diets in the blood variables and carcase characteristics, except for total visceral organ weight, increased in all experimental groups. 6. Most of the intestinal villus heights, villus areas, epithelial cell areas and cell mitosis tended to increase with increase in FPP concentrations; duodenal villus height and cell mitosis in the 2·0 and 4·0% dietary FPP groups, and jejunal cell mitosis in all experimental groups were significantly increased. Compared with flat cells on the villus apical surface in the 0% FPP group, all experimental groups had protuberant cells in all intestinal parts. 7. In conclusion, hypertrophy of the villi and epithelial cells was observed in the present study, indicating improved growth performance, especially in the 4·0% dietary FPP group. Furthermore, increased total visceral organ weights suggested that FPP has no harmful effects on broilers. 相似文献
18.
1. Growth, food intake, and food preference were measured in two experimental lines (White Rocks and White Leghorns) of chickens fed diets varying in content of lysine, methionine, or tryptophan. Diet A was balanced in all amino acids, while the remaining 6 diets were moderately ( ～ 30%) or slightly ( ～ 15%) deficient in either lysine, methionine, or tryptophan relative to NRC recommendations for broiler diets. 2. Body weight and food utilisation efficiency of White Leghorns at 10 d of age were not affected by diet, whereas the lower concentrations of lysine and methionine depressed these traits in White Rocks. 3. Tryptophan deficiency reduced food intake of White Leghorns, but not White Rocks. 4. With choice feeding of balanced and deficient diets from day 10 to 16, preferences between the diets were minimal for White Leghorns, whereas for White Rocks there was an almost immediate preference for the balanced diet, followed by lack of preference or preference for the deficient diet. 5. Apparently for some genetic stocks there is rapid adjustment to deficiencies in these amino acids with overconsumption, followed by compensation for preference of the balanced diet. The response, however, will vary depending on the deficient amino acid. 相似文献
19.
To determine the effectiveness of dietary lysine supplementation in cats with enzootic upper respiratory disease (URD), 50 cats were fed a ration containing 11 or 51 g lysine/kg diet for 52 days. Food intake, body weight, clinical signs, plasma amino acid concentrations and presence of Chlamydophila felis or feline herpesvirus (FHV)-1 DNA within the conjunctival fornix were assessed. Food and lysine intake of both dietary groups decreased between days 17 and 22, coinciding with peak disease and viral presence. Mean disease score for cats fed the supplemented ration (0.94) was higher than for those fed the basal diet (0.21); however, this could be attributed to a small subset of male cats which demonstrated fighting behavior that may have contributed to stress within that cage. FHV-1 DNA was detected on 12 occasions in six cats receiving the supplemented diet and on one occasion in one cat fed the basal diet. C felis DNA was never detected. Mean plasma arginine concentration was lower and plasma lysine concentration was higher in supplemented cats. Mean plasma arginine concentration declined throughout the study in both dietary groups. Data from the present study raise important questions but do not permit a definitive conclusion regarding the efficacy of dietary lysine supplementation in cats with enzootic URD. 相似文献
20.
An experiment was carried out to establish the effect on the growth of pigs of including blood meal or lysine in diets containing gossypol from cottonseed cake. Forty Landrace x Large White pigs (20 of each sex) were randomly allocated to 5 treatments of 8 pigs each in a 2 x 2 factorial design with two levels of lysine or two levels of blood meal in the diets plus a control diet. The pigs were fed different diets and slaughtered at 75.0 +/- 2.0 kg live weight for carcase analysis. Supplementing the diets with blood meal resulted in higher live weight gains (p<0.001) and improved feed conversion ratios (p<0.001) than supplementing with lysine. Pigs fed the higher level of cottonseed cake showed a significant (p<0.001) depression in live weight gain and feed conversion ratio compared to those fed a low level of the cake. There was no significant difference (p>0.05) in intake in the pigs fed diets with cottonseed cake including blood meal or synthetic lysine. The kidney and liver weights of the pigs fed the diets with a higher level of cottonseed cake were significantly greater (p<0.001) than in those fed the lower level, but when the diets containing cottonseed cake were supplemented with blood meal or lysine at the same level there was no significant difference (p>0.05) in the weights of these organs. Lysine or other factors derived from blood meal appear to be more efficient than synthetic lysine in reducing the adverse effects of gossypol. 相似文献
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