Received May 21, 2014; accepted August 10, 2014 相似文献
2. Birds were randomly allotted to one of the 4 treatments in a 2 × 2 factorial arrangement (12 replicateswith 15 broilers per replicate) with two levels of nutrient density [high nutrient density (metabolisable energy (ME) 12.7 MJ/kg and crude protein (CP) 230.3 g/kg for 1–7 d; ME 13.2 MJ/kg and CP 220.3 g/kg for 8–28 d) or low nutrient density (ME 12.1 MJ/kg and CP 220.2 g/kg for 0–7 d; ME 12.6 MJ/kg and CP 209.8 g/kg for 8–28 d)] and 0 or 2 g/kg probiotics (1.0 × 1010 viable spores/g of Bacillus subtilis endospores and 1.0 × 109 viable spores/g of Clostridium butyricum).
3. The high-nutrient-density diet increased body weight gain (BWG), feed conversion ratio (FCR), serum cholesterol and triglyceride concentration relative to the low-nutrient-density diet. High-nutrient-density diet reduced water loss ratio of breast muscle, liver and fat relative to body weight compared to low-nutrient density-diet. The inclusion of probiotics increased BWG and feed intake throughout the experiment. Dietary probiotics increased the percentage of blood lymphocytes and relative weight of spleen and bursa of Fabricius when compared to the non-probiotic treatment. The inclusion of probiotics decreased serum cholesterol and triglyceride concentrations and lightness (L*) value of breast meat compared to the non-probiotic-supplemented diet.
4. In conclusion, high dietary nutrient density increased growth performance and serum cholesterol and triglyceride concentrations in broiler chickens. The inclusion of probiotics increased growth performance but reduced serum cholesterol and triglyceride concentrations. The positive effect of probiotic supplementation on growth performance was reduced by the high-nutrient-density diet during the first week of life. 相似文献
2. A total of 900-d-old Arbor Acres broilers were allocated to three experimental treatments for 6 weeks. Chicks were administered with R. palustris in drinking water as follows: (i) control group without R. palustris; (ii) treatment 1 (R1) with R. palustris of 8 × 109 cells per chick per day in drinking water; (iii) treatment 2 (R2) with R. palustris of 1.6 × 1010 cells per chick per day in drinking water.
3. The results showed that, compared with that of control, both groups of R. palustris treatment increased daily weight gain and improved feed conversion ratio of broiler chickens significantly during the whole growing period of 6 weeks.
4. Both total and glutamic acid contents of chicken breast fillet in R. palustris treatment R2 were higher, while the fat content was lower, than those of the control group. Furthermore, R. palustris treatments also improved sensory attributes of chicken breast fillet.
5. As a probiotic providing rich nutrients and biological active substances, R. palustris administration in drinking water displayed a growth promoting effect and improved meat quality of broiler chickens. 相似文献
Received December 19, 2014; accepted May 4, 2015 相似文献
Received December 9, 2014; accepted February 7, 2015 相似文献
2. Specific pathogen free chickens were inoculated intranasally with 106EID50 of influenza virus or uninfected. After specified time intervals, 107 CFU E. coli or phosphate-buffered saline was inoculated. The presence of lesions, the number of respiratory phagocytes in the respiratory lavage fluid and the E. coli load in the lung were determined after different time intervals.
3. Compared with the number of lesions in chickens receiving only E. coli inoculation, the number lesions in co-infected chickens were increased at 0- and 3-d time intervals, but reduced in the groups at 6- and 9-d intervals between co-infection.
4. At 1–3 d after E. coli inoculation, the number of lesions chickens was correlated with the number of respiratory phagocytes harvested and related to the E. coli load in the lungs at 5 d.
5. These results suggest that the lesions caused by E. coli in chickens were increased within a 0–3 d interval following H9N2 virus inoculation and that this effect is related to the number of respiratory phagocytes. 相似文献
Received August 11, 2014; accepted November 14, 2014 相似文献
2. The equations relating minimal resting metabolic rate (oxygen consumption, ml/bird h,y) and body weight (W) were: males 45 to 497 g, y = 3.2 W0.882 597 to 3000 g, y = 40.5 W0.483; females 45 to 514 g, y = 2.52 W0.881; 514 to 2500 g,y = 12.3 W0.627.
3. The relationship between lower critical temperature (Tcl , °C,y) and age (d, x) may be described by the following equations: chicks 1 to 21 d, y = 34.2 ‐ 0.32 x; 14 to 63 d,y = 49.4 × ?0194.
4. The relationship between Tcl and W may be described by one equation for both sexes between 100 and 3000 g, y = 62.15 W?0.135..
5. The equations for Tcl and data for upper critical temperature (Tcu ) could be used to obtain maximal performance from broilers, with reduced costs, by providing a suitable environment related to age or body weight. 相似文献
2. Blood collections from the cutaneous ulnar or medial metatarsal veins of birds yielded adequate blood volume (2–3 ml) draws. The experiment was a 2 × 2 × 3 factorial arrangement of treatments, with two levels of DNase (0 and TURBO DNA-free Kit), two levels of Cleanup (0 and RNeasy MinElute Cleanup Kit), and three anticoagulants (no anticoagulant, EDTA, or sodium citrate).
3. RNA was isolated successfully by adding TRIzol LS to 0.25 ml of chicken whole blood at 3:1 ratio. From 0.125 ml of avian whole blood, 2–3 µg of RNA with RNA integrity number values of 7.75 was successfully isolated with the TRIzol LS extraction and an RNeasy MinElute Cleanup Kit.
4. This reliable protocol can be used to extract high yield and quality of total RNA from a small amount of whole blood. 相似文献
Received July 31, 2014; accepted March 2, 2015 相似文献
2. The occurrence of E. coli in different categories of table eggs collected from markets was evaluated. Isolates were analysed for the presence of virulence genes, antibiotic susceptibility pattern and efficacy of peracetic acid and chlorine for the purpose of decontaminating table eggs.
3. Significant differences were observed in the occurrence of E. coli between different groups viz. processed (cleaned, washed, sanitised and packed eggs), unprocessed (un-cleaned, un-sanitised and loose eggs) and free range (eggs obtained from backyard poultry) table eggs. Overall, E. coli occurred in table eggs at 28.6% with 22.9, 29.2 and 50.0% occurrence in processed, unprocessed and free-range table eggs, respectively.
4. A total of 24 isolates of E. coli were obtained and screened for virulence genes viz. STH, SLT1/2 and INVE genes. Of the 24 isolates recovered, 10 typeable isolates belonged to O141, O119, O9, O120 and O101 serotypes, while the remaining 14 were untypeable. Antibiograms of the isolates showed multiple antimicrobial resistance (MAR) index in the range of 0.13–0.40.
5. Peracetic acid (PAA) and chlorine (CL) were studied for their sanitisation efficacy; concentrations of 100 mg/kg of PAA and 200 mg/kg of CL completely inactivated E. coli over the egg surface and also resulted in 2.58 and 2.38 log reduction in total viable counts (TVC), respectively.
6. The presence of virulence-associated shiga-like toxin (SLT1/2) and invasion E (INVE) genes and antimicrobial resistance among the emerging serotypes of pathogenic E. coli isolated from table eggs has public health implications. It underscores the need to implement better management practices across the production systems and marketing channels to produce E. coli-free wholesome eggs for consumers. 相似文献
2. A questionnaire about the rearing period was completed and caecal samples were collected from 121 broiler flocks in Brittany, France, during 2008.
3. Campylobacter was isolated in 87 out of 121 flocks – a prevalence of 71.9% (95% CI, 63.7–80.1%), including 40.5% of Campylobacter jejuni and 29.8% of Campylobacter coli.
4. The average concentration, in positive flocks, was 7.96 log10 cfu/g and ranged from 3.15 to 10.32 log10 cfu/g.
5. The average concentration by species was: 7.57 log10 cfu/g for C. jejuni and 8.44 log10 cfu/g for C. coli.
6. There was a seasonal effect, with increased risk of Campylobacter colonisation in June, July and August (odds ratio (OR) = 9.59, 95% CI 1.15–79.75).
7. The other factors, associated with lower risk of Campylobacter colonisation, were the acidification of drinking water (OR = 0.33, 95% CI 0.13–0.86), antibiotic treatment at the beginning of the rearing period (OR = 0.20, 95% CI 0.07–0.55) and rodent control around the house (OR = 0.18, 95% CI 0.03–0.95).
8. The results show that hygiene practices and biosecurity measures could lead to a reduction in Campylobacter colonisation. 相似文献
2. Body weight, egg number and egg weight all responded (P < 0–001) to energy intake, and as judged by regression analyses, these responses had stabilised by the fifth period.
3. For a near‐maximum egg output of 48 g/bird d, the difference between the ME requirement of the average bird and of the flock, estimated from linear and curvilinear models respectively, was 20–5%.
4. The ME requirement (Y, kj/bird d) of the average bird for egg production (E, g/bird d) and maintenance of metabolic body size (kg W°. 75 ) corrected to an ambient temperature of 22 °C is given by the equation, Y = 440W 0.75 + 8.96 E 相似文献
2. Four different alkaliphilic microbes were isolated and shown to degrade poultry feathers.
3. Two of the isolates were phylogenetically identified as Lysinibacillus and the others were identified as Nocardiopsis and Micrococcus.
4. The best microbial co-culture for white and black feather degradation was optimised for pH, temperature and relative population of the isolates to achieve almost 96% of degradation compared with a maximum of 31% when applying each isolate individually.
5. The maximum activity of keratinase was estimated to be 1.5 U/ml after 3 d for white feathers and 0.6 U/ml after 4 d for black feathers in a basal medium containing feather as the main carbon source. Additionally, non-denaturing polyacrylamide gel electrophoresis showed 4 and 3 protease activity bands for white and black feather, respectively.
6. This study provides a robust method to develop potential new mixtures of microorganisms that are able to degrade both white and black feathers by applying a Central Composite Design. 相似文献
2. A diminution of the Na+ and K+ content of the shell membranes of fertile eggs was not associated with changes in the dimensions of the glyco‐protein mantle on the cores of the individual fibres of the membranes. There was, however, a progressive deterioration in the limiting membrane of fertile but not of infertile eggs.
3. It was concluded that changes in the O2 resistance of the integument of fertile eggs were not a product of change in either of the shell membranes but of damage caused to the limiting membrane by the chorioallantois. 相似文献
2. Micro-organisms were grown anaerobically in MRS broth, and 106 CFU/ml of bacteria were administered orally to mixed-sex, 1-d-old broiler chickens weekly for 4 weeks and to 23-week-old layer hens weekly for 6 weeks.
3. The 4 strains were evaluated for their effects on synthesis of CLA in hen eggs and broiler meat cuts.
4. Administration of pure Lactobacillus and isolated L. reuteri strains from camel, cattle, goat and sheep led to significantly increased CLA concentrations of 0.2–1.2 mg/g of fat in eggs and 0.3–1.88 mg/g of fat in broiler chicken flesh homogenates of leg, thigh and breast.
5. These data demonstrate that lactic acid bacteria of animal origin (L. reuteri) significantly enhanced CLA synthesis in both eggs and broiler meat cuts. 相似文献
2. In vitro tests indicated that PWT was highly effective for reducing Campylobacter jejuni and Campylobacter coli at the recommended concentration in water, reducing populations by greater than 7 log10 CFU/ml after 24 h exposure. The decrease in the number of Salmonella serovar Enteritidis and Escherichia coli was not significant.
3. Addition of PWT to the broiler drinking water for the first 7 d, 2 d before and 2 d after each feed change and at feed withdrawal prior to slaughter or only after feed withdrawal had no effect on the number of Campylobacter in caecal samples on farm before thinning and depopulation compared to untreated controls.
4. Although PWT was effective for reducing Campylobacter in water, the results suggest that it does not reduce the number of Campylobacter in the caeca of broilers prior to slaughter under the conditions used in the study. 相似文献
2. TEX-OE® is a patented total extract of the fruit of Opuntia ficus indica, which has been demonstrated to accelerate the development of HSPs in several animal species.
3. One-day-old commercial broiler chicks were treated with TEX-OE®; HSP was measured by enzyme-linked immunosorbent assay (ELISA), and a large commercial field trial investigated key performance indicators (KPIs) in treated versus untreated controls chicks.
4. TEX-OE® significantly increased HSP concentrations in treated chicks versus controls. Final cumulative mortality, liveweight and percentage factory-rejects were better than in controls.
5. The accelerated HSP response may enable chicks to cope with early stressors, which is reflected in improved KPIs. 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