2. There were no differences among the diets on the growth performance and digestive organ size.
3. The villus height and cell mitosis number of all intestinal segments did not change in any treatment. The ileal villus area, duodenal cell area, duodenal and jejunal goblet cell number in the 50WPR group increased significantly relative to the control but not when enzyme was included.
4. In the scanning electron microscope results, all experimental groups showed clear protuberant cells and cell clusters on the villus apical surface of the duodenum. In the jejunum, cell clusters and areas having cells with no microvilli were frequently found in both the 50WPR and 50WPR + enzyme groups.
5. In conclusion, broilers fed on diets replacing maize with WPR showed hypertrophied villi of duodenum and ileum and epithelial cells in duodenum and jejunum, especially in the 50WPR group, without negatively affecting growth performance. These findings suggest that WPR can replace maize up to a level of 50% (283.0 g/kg, starter, and 250.0 g/kg, finisher) in broiler diets without enzyme supplementation. However, further studies are needed to improve our knowledge of the influence of WPR on higher numbers of birds. 相似文献
2. An economic model of these responses was developed in which the temperature and age at slaughter are optimised, given food and live body weight prices.
3. If a finisher diet of 13.3 MJ ME and 199 g protein/kg costing 150 £/tonne is fed, and provided the grower diet contains 13.5 MJ and 221 g protein/kg, the optimum temperature is 21 to 22 °C for male and female broilers slaughtered at 61 and 54 d respectively with a live body weight value of £0.50/kg. 相似文献
2. A total of 280 one-d-old Ross 308 chickens were used in a completely randomised design with two dietary treatments (7 replicates of 20 birds/treatment); air-dry feed versus the same feed in moist form (water:feed ratio of 1.3:1, on a weight basis), inoculated with Lactobacillus plantarum NCIMB 40087 (9 log10 CFU/kg feed) and batch-fermented for 48 h at 26°C. The birds were given starter (d 0–13), grower (d 4–26) and finisher (d 27–39) diets ad libitum. At the end of the grower and finisher period, two birds per pen were removed to sample intestinal contents for cultivating bacteria and intestinal tissue to determine villus height and crypt depth.
3. Fermented moist feed (FMF) batches showed good characteristics, with a pH between 3.9 and 4.4 and DL-lactic acid between 137 and 286 mmol/l. Daily feed intake and gain were reduced considerably in the FMF group in the starter (–40 and –44%, respectively) and grower (–23 and –16%) period, though in the finisher period these birds performed better, with an improved feed utilisation. Concomitant with the latter, villus height at the mid-jejunum and mid-ileum on d 39 was higher (+22.6% and +16.0%). Significantly more Lactobacilli and less coliforms were found in the foregut and less Streptococci in ileum and caeca of birds given FMF.
4. This trial showed that FMF was detrimental for early bird growth but affected beneficially feed efficiency, the composition of the gut bacteria and villus height in the small intestine in the finisher period in broilers. 相似文献
2. At 8 weeks of age, birds receiving 50 and 75 g sand/kg diet were significantly heavier than those receiving the basal diet and 100 g sand/kg diet.
3. Birds receiving 0 and 100 g sand/kg diet consumed similar quantities of basal diet and yielded similar corrected food:gain ratios.
4. Dietary dilution with sand had no significant effect on mortality, apparent carcase yield, preventriculus weight, gizzard weight and intestinal length. Crop weights were significantly greater in birds given 100 g sand/kg diet to the age of 4 weeks.
5. The litter moisture content was significantly less in pens containing birds receiving 75 or 100 g sand/kg diet after 5 weeks of age. 相似文献
2. A total of 810 male chicks were reared in commercial conditions on floor pens till d 24. Then, birds were weighed and used in a completely randomised design experiment with a 3 × 3 factorial arrangement, including three levels of conditioning times (0, 2 and 4 min) and three PSB levels (0, 7.5 and 15 g/kg diet). Each of the 9 diets fed to 6 replicates group of 15 birds each.
3. The results showed that 2-min steam conditioning and 15 g/kg PSB supplementation significantly increased pellet durability index (PDI) and hardness, and decreased electrical consumption of pelleting. Diets had no significant effects on body weight, feed intake and feed conversion ratio. Although dietary treatments did not influence relative weight and length of three segments of small intestine, 2-min steam conditioning significantly improved villus height (VH) and crypt depth. Steam conditioning of diet for 2 min significantly increased apparent metabolisable energy (AME), ether extract (EE), calcium (Ca) and dry matter (DM) retention in birds measured during 38–42 d of age.
4. It could be concluded that 2-min steam conditioning improved PDI and hardness, VH and nutrient retention (AME, EE, Ca and DM), but did not affect growth performance in broilers during finisher period. 相似文献
2. A total of 540 one-d-old Ross 308 broiler chicks were allotted to 9 experimental diets, including three ME levels (control, or 0.42 or 0.84 MJ/kg higher ME) and three types of supplemental lipotropic factors (control, 1000 mg/kg of choline or 100 mg/kg of carnitine) as a 3 × 3 factorial arrangement of treatments. Average daily feed intake (ADFI), average daily gain (ADG) and feed conversion ratio (FCR) were recorded during the starter (1–14 d of age), grower (15–28 d of age) and finisher (29–42 d of age) periods.
3. Results showed that the increase in dietary ME level had no impact on ADFI during the starter and grower periods. In the finisher period, increasing dietary ME decreased (P < 0.001) ADFI. Raising dietary ME level by 0.84 MJ/kg resulted in the greater ADG during the grower (P < 0.05) and finisher (P < 0.001) periods. Moreover, an improvement in FCR was observed with feeding the +0.84 MJ/kg diet. Dietary supplementation of lipotropic factors improved FCR values in birds fed the control and +0.84 MJ/kg diets during the grower and finisher periods (P < 0.01).
4. Dietary supplementation of both choline and carnitine increased (P < 0.05) moisture content of leg muscle, although malondialdehyde content of leg muscle was decreased (P < 0.01) in the presence of both lipotropic factors. Dietary supplementation of carnitine decreased (P < 0.01) leg fat content, and this effect was more obvious with higher ME levels, giving a significant ME × lipotrope interaction (P < 0.05). Higher dietary ME level (+0.84 MJ/kg) reduced (P < 0.05) protein content of breast muscle, but this factor was increased (P < 0.05) by dietary supplementation of choline.
5. Although dietary ME level had no marked effect on carcass yield and internal organ weight, supplemental choline increased (P < 0.01) carcass yield.
6. The results from this trial indicated that dietary supplementation with lipotropic factors can improve feed efficiency in high energy diets. In addition, oxidative stability of leg/breast muscles was improved as a result of dietary supplementation with choline or carnitine. 相似文献
2. A low-crude protein (CP) diet was formulated to meet the requirements of all amino acids (AA) supplied by the control diet except for Val, Ile, Arg and Gly. The other experimental diets were obtained by the isolated or combined supplementation of the studied AA in the low-CP diet.
3. Growth, serum parameters and litter characteristics were taken in both of the experiments. Carcass measurements were taken in Experiment 2.
4. In the starter and grower phases, low-CP diets without supplementation resulted in birds with a poorer weight gain and feed conversion than those of the birds that received the control diet.
5. In the starter phase, individual supplementation with Val and Gly, but not Ile and Arg, restored the weight gain of the birds, while diets with the addition of Val + Gly, Val + Ile + Arg, Val + Ile + Gly and Val + Ile + Arg + Gly restored their feed conversion.
6. In the grower phase, weight gain was re-established at the same rate as the control diet for the diets supplemented with Val + Ile, Val + Ile + Arg, Val + Ile + Gly and Val + Ile + Arg + Gly. However, the feed conversion was restored only in birds that received the diet supplemented with all studied AA.
7. The supplementation of Val and Gly in low-CP diets was sufficient to avoid adverse effects in the performance and serum parameters of broilers in the starter phase. However, birds in the grower phase required the combined supplementation of Val, Ile, Arg and Gly, to prevent compromised performance. 相似文献
2. Cumulative food consumption and body weight at 42, 49 and 56 d decreased with increasing temperature.
3. There were no interactions between temperature and dietary nutrient concentration. 相似文献
2. Although the protein content of all tissues varied with age, the only statistically significant effect was on the level of protein in the gizzard.
3. The moisture content of the gizzard was significantly affected by age and blood by age and sex.
4. The fat content of the gizzard was significantly affected by age, as was the effect of sex on the fat content of blood.
5. The ash contents of heart and gizzard were significantly affected by age.
6. The phosphorus contents of the gizzard, heart and liver were significantly affected by age, as were the chloride content of heart and the calcium content of the liver. Blood potassium was significantly affected by sex. Fluctuations in the contents of other elements are discussed.
7. The variability in organ composition is discussed with respect to the degree of trimming and preparation of the samples. 相似文献
2. During the rapid‐growth phase (yolk deposition) of the oocyte, i.e. an increase in size from about 9 mm diameter to 35 mm diameter, there is about a 15‐fold increase in its surface area. During this time the number of granulosa cells adjacent to the oocyte increases by about 5‐fold.
3. The granulosa cells become flatter during the growth period of the follicle, consequently increasing their surface area adjacent to the oocyte by about 3‐fold.
4. Together the change in shape of the granulosa cells and the increase in their number account for the increase in area of the granulosa layer during follicular growth.
5. Measurement of the DNA content of the granulosa layer indicated a progressive decrease in the cellular content of DNA as the follicle matures. 相似文献
2. Protein and energy metabolism were studied in males from these selected lines fed on a diet of intermediate protein content.
3. All selected birds retained more nitrogen than those studied 10 years previously.
4. There was no difference in nitrogen retention between groups, although relative growth rate of group B birds was higher.
5. Heat productions relative to gross energy intake were 0.38 (group B) and 045 (group A). Energy retentions relative to gross energy intake were 0.39 (group B) and 0.35 (group A); the difference being primarily due to higher fat retention in group B.
6. Using a common maintenance requirement for metabolisable energy, group B utilised metabolisable energy for growth (0.78) better than did group A (0.71).
7. At 53 d of age plasma glucose (10%) and insulin (50%) were higher in group B than in group A. 相似文献
2. Dry plucking increased weight loss due to plucking and eviscerating, and reduced chilled carcass yield.
3. Dry eviscerating increased carcass water uptake during chilling.
4. Pre‐chilling with running water increased carcass water uptake compared with chilling in ice and water alone.
5. Water uptake during chilling appeared to be increased by longer eviscerating time. 相似文献
2. A total of 240 Arbor Acre chickens were randomly assigned into 4 treatment groups, each treatment containing 6 replicates of 10 chickens each. Group 1 was the control group without LA supplementation; Group 2 was supplied with LA in the starter period; Group 3 was supplied with LA in the grower period; and Group 4 was supplied with LA in the whole period.
3. The results showed that LA supplementation improved average feed intake and body weight gain in all three experimental groups, especially in Group 2. LA supplementation significantly decreased abdominal fat yield in Groups 3 and 4.
4. LA supplementation all improved hepatic total antioxidant capacity, the level of glutathione, the activities of total superoxide dismutase, catalase (CAT) and glutathione peroxidase, in particular in Group 4. LA supplementation decreased the activity of liver xanthine oxidase (XO) in all experimental groups, and that of liver monoamine oxidase in Group 3. The activities of liver CAT and XO in Group 2 were higher than that in Group 3. LA supplementation elevated the pH24 h and decreased drip loss in breast meat in Groups 3 and 4.
5. In conclusion, LA supplementation can improve growth performance, antioxidant properties and meat quality in broiler chicken. LA supplementation in the starter period can improve growth performance and supplementation in the grower – and in the whole period can improve carcass characteristics. There was no significant difference in meat quality of broiler chickens fed on LA-supplemented diet in different stages. 相似文献
2. Dietary fibre and physical form did not significantly affect food consumption. Growth and food utilisation improved with pelleting and decreased with increasing fibre content. The interaction between fibre and physical form was also significant.
3. At similar food intakes, high fibre contents increased relative length and weight of the intestine and caeca. Gizzards were heavier in broilers fed on four of the five mash diets. 相似文献
2. The weight, length and cross-sectional area of tibiae and femora were measured, densitometric measurements and tests of strength were determined and dimensions were calculated.
3. Breed and caponisation did not influence bone weight and length. Higher mechanical strength of the femur was found in entire males, mainly in the Polbar breed. Tibial strength was reduced in capons of the Green Partridge breed. Maximum elastic strength was greater in the Polbar, irrespective of caponisation. Bone cross-sectional area was influenced by breed, while caponisation reduced femoral bone mineral density in both breeds.
4. Caponisation thus increased growth rate but had adverse effects on bone development.
5. Caponisation had fewer negative effects in the Polbar than in the Greenleg Partridge. 相似文献
2. The different varieties of wheat investigated contained different proportions of water‐soluble to water‐insoluble hemicelluloses.
3. By comparison of the arabinose to xylose ratios it was concluded that water‐soluble and insoluble arabinoxylans of wheat were branched to the same degree.
4. Starch from six wheat varieties grown in the U.K. was very well digested by adult cockerels and true metabolisable energy values of the wheats were high.
5. Small amounts of cell wall carbohydrates were digested by adult cockerels. 相似文献
2. This study includes the analysis of ostrich body weight (BW) by modelling growth with linear polynomial and non-linear functions for all the data not separated for treatments. In total, 3378 BW recordings of 90 animals were collected weekly from hatch (d 0) to 287 d (41 weeks) of age.
3. Seven non-linear growth models and three linear polynomial models were fitted to the data. The growth functions were compared by using Akaike’s information criterion (AIC). For the non-linear models, the Bridges and Janoschek models had the lowest AIC values for the H treatment, while the Richards curve had the lowest value for M and the von Bertalanffy for the L treatment.
4. For the linear polynomial models, the linear polynomial of the third degree had the lowest AIC values for all three treatments, thus making it the most suitable model for the data; therefore, the predictions of this model were used to interpret the growth data. Significant differences were found between treatments for growth data.
5. The results from this study can aid in describing the growth of ostriches subjected to optimum feeding conditions. This information can also be used in research when modelling the nutrient requirements of growing birds. 相似文献
2. Protein content generally increased with age in all muscles and decreased in skin. Protein content in skin of males was always higher than that in females.
3. Moisture content in all muscles decreased with age. In the skin, moisture decreased with age considerably more in females than in males.
4. Fat content increased with age in all tissues, while ash content of breast, thigh and skin decreased with age.
5. Phosphorus, chloride, magnesium and potassium all decreased with age in all the tissues. Thigh and skin calcium content were affected by age, as was the sodium content of drumstick and skin.
6. The sex effect on the inorganic constituents was variable. 相似文献
2. Guinea fowls had higher body weight, hot carcass weight, cold dressed weight and breast weight than chickens.
3. Guinea fowls had more dry matter, protein and less fat than chickens. Ash content did not differ between guinea fowls and chickens. Protein and fat increased, whereas dry matter and ash decreased with age (P < 0.05)
4. Chicken meat was lighter, less red and more yellow than guinea fowl meat. Cooking loss was higher in guinea fowls, male and grower birds than chickens, females and adult birds, respectively. Shear force was affected by age, as mature birds had a higher value than growers.
5. Guinea fowl carcasses contained more meat that was leaner, higher in protein and redder compared with chicken meat. As age increased the meat increased in protein and fat content and shear force, whereas colour became darker, redder and yellower. 相似文献
2. Imaging was performed two times daily. To localise chickens within the pen, an ellipse fitting algorithm was used and the chickens’ head and tail removed using the Chan–Vese method.
3. The correlations between the body weight and 6 physical extracted features indicated that there were strong correlations between body weight and the 5 features including area, perimeter, convex area, major and minor axis length.
5. According to statistical analysis there was no significant difference between morning and afternoon data over 42 d.
6. In an attempt to improve the accuracy of live weight approximation different ANN techniques, including Bayesian regulation, Levenberg–Marquardt, Scaled conjugate gradient and gradient descent were used. Bayesian regulation with R2 value of 0.98 was the best network for prediction of broiler weight.
7. The accuracy of the machine vision technique was examined and most errors were less than 50 g. 相似文献