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81.
A total of 336 one‐day‐old Hubbard broiler chickens were randomly distributed among 8 groups, each containing six replicates (7 chickens/replicate). From 1 to 40 days of age, the groups fed the same starter, grower and finisher diets. The control group was unsupplemented; zinc bacitracin (ZnB) group received the antibiotic at 0.5 g/kg; fungal phytase (FP) groups received 250, 500 and 1000 U/kg diet of Aspergillus niger phytase (FP_250, FP_500 and FP_1000 groups), respectively; bacterial phyatse (BP) groups received 250, 500 and 1000 U/kg diet of Escherichia coli phytase (BP_250EP, BP_500EP and BP_1000EP groups) respectively. Considering the whole experimental period, body weight gain was unaffected by ZnB and different concentrations of bacterial and fungal phytase; however, the feed conversion ratio of the group fed a diet supplemented with 500 U of BP was better (p < 0.01) than those fed with a diet supplemented with 500 U of FP. BP_250 group had a higher (p < 0.05) apparent digestibility of ether extract compared to FP_250 group. In conclusion, bacterial phytase at 500 U may enhance performance of broiler chickens fed during days 1–40 of age and yield similar growth performance and economic efficiency to those of eB‐supplemented groups.  相似文献   
82.
  1. Quantitative real-time PCR was carried out to evaluate gene expression of heat shock proteins (HSP) (HSP27, HSP56, HSP60, HSP70, HSP90 and ubiquitin) in the brain (hindbrain, midbrain, forebrain) of chickens with cold-induced pulmonary hypertension.

  2. The ratio of the right ventricle to the total ventricle (index of pulmonary hypertension in chickens) was increased in the cold-induced pulmonary hypertensive chickens at 42 d of age compared with control. The HSP genes were expressed in the three parts of the brain in the two experimental groups.

  3. In the hindbrain of cold-induced pulmonary hypertensive chickens, the relative gene expression of HSP27, HSP60, HSP70 and HSP90 was decreased while gene expression of HSP56 and ubiquitin was increased compared with controls.

  4. In the midbrain of cold induced-pulmonary hypertensive chickens, the expression of HSP56, HSP60, HSP70 and ubiquitin genes was increased compared with controls while HSP27 and HSP90 were decreased.

  5. In the forebrain of cold induced-pulmonary hypertensive chickens, the expression of HSP56, HSP60, HSP70 and ubiquitin genes was increased while the expression of the HSP27 gene was decreased compared with controls.

  6. It is concluded that overexpression of HSPs in the forebrain and midbrain probably delays the pathological process of cold stress whereas diminished expression of HSP genes in the hindbrain may affect the normal function of brain centres in this area to exacerbate pulmonary hypertension.

  相似文献   
83.
The objective of this study was to compare the reproductive performance of cows affected by clinical endometritis (CE) following treatment with an intrauterine infusion of 50% dextrose solutions (DEX) and liquid paraffin (LP) as alternative therapies with routine treatments including PGF injection and intrauterine infusion of oxytetracycline (OTC). Moreover, the reproductive indices of cows treated with endometritis were compared with those of healthy ones. At postpartum reproductive tract examination (28–35 DIM) in one Iranian dairy farm, cows with CE without any selection were assigned to four groups: (a) OTC, a common treatment in Iran, was administered (5 g) to 396 cows, (b) PGF2α (PG) was injected to 496 cows, (c) dextrose solution (DEX): intrauterine infusion of 50% dextrose solution (200 ml) was done in 427 cows, and (d) liquid paraffin (LP) was administered (100 ml) to 423 cows via intrauterine route. We further assigned 2,233 clinically healthy cows to the control group. The incidence of endometritis was 41.6% in this study. Based on the results of reproductive indices including median days to first AI, days open (DO), first service conception rate, conception rate in 2nd and 3rd services, conception rate in all three services, pregnancy rate < 100 days and pregnancy rate < 200 days, except for median days to first AI in other reproductive indexes, reproductive performance was significantly lower in LP group compared with the healthy cows and other treatment groups (p < 0.05). Except for the first service conception rate and proportion of cows pregnant before 100 days in milk (DIM), there existed no significant difference between the DEX group and the control as far as reproductive performance is concerned (p ≥ 0.05). The first service conception rate was recognizably lower in DEX group compared with OTC and PG (p < 0.05). In conclusion, the use of a non‐antibiotic special solution of dextrose 50% is a good alternative to antibiotic agents concerning the treatment of CE in dairy cows.  相似文献   
84.
Two experiments were carried out to determine the efficiency of supplementation of ram semen extender with caffeine on chilled storage and frozen capacity of spermatozoa. In the first experiment, eighty ejaculates were collected by an artificial vagina from five adult Barki rams, aged 2–3 years and weighted 45.0 ± 2.0 kg throughout the experimental period (January to February 2017). The ejaculates were pooled and diluted (1:10) with tris‐citric egg yolk extender and were split into five groups. Group 1 served as control, whereas groups 2‐5 were supplemented with 0.1, 0.2, 0.3 and 0.4 mM caffeine. All diluted semen specimens were evaluated for physical characteristics immediately after dilution (T0) and throughout preservation period of 48 hr at 4°C. Simultaneously, oxidative stress and indices such as total antioxidant capacity (TAC), malondialdehyde concentrations (MDA) and alkaline transaminase (AKP) concentrations and value of resazurin reduction test (RRT) were determined. In the second experiment, the raw pooled ejaculates were diluted (1:10) with glycerolated tris‐citric egg yolk extender, receiving the previously mentioned caffeine levels. The post‐thaw assessment of cryopreserved spermatozoa, in all groups, was conducted by a computer‐assisted sperm analysis (CASA) system. The results revealed that adding caffeine to ram semen extender at low (0.1 mM) or medium (0.2 mM) levels had positive impact on both physical characteristics of ram sperm and the enzymatic activities compared to the other semen groups. Caffeine supplementation also enhanced post‐thaw sperm dynamics, which implies its potential as an exogenous antioxidant supplement.  相似文献   
85.
Background: The current study was carried out to evaluate the effects of mycotoxin biodegradation agent(MBA, composed of Bacillus subtilis ANSB01 G and Devosia sp. ANSB714) on relieving zearalenone(ZEA) and deoxynivalenol(DON) toxicosis in immature gilts.Methods: A total of forty pre-pubertal female gilts(61.42 ± 1.18 kg) were randomly allocated to four diet treatments: CO(positive control); MO(negative control, ZEA 596.86 μg/kg feed and DON 796 μg/kg feed);COA(CO + 2 g MBA/kg feed); MOA(MO + 2 g MBA/kg feed). Each treatment contained 10 replicates with 1 gilt per replicate. Gilts were housed in an environmentally controlled room with the partially slatted floor.Results: During the entire experimental period of 28 d, average daily gain(ADG) and average daily feed intake(ADFI)of gilts in MO group was significantly reduced compared with those in CO group. The vulva size of gilts was significantly higher in MO group than CO group. In addition, significant increases in the plasma levels of Ig A,Ig G, IL-8, IL-10 and PRL were determined in MO group compared with that in CO group. ZEA and DON in the diet upregulated apoptotic caspase-3 in ovaries and uteri, along with down-regulated the anti-apoptotic protein Bcl-2 in ovaries. The supplementation of MBA into diets co-contaminated with ZEA and DON significantly increased ADG, decreased the vulva sizes, reduced the levels of Ig G, IL-8 and PRL in plasma, and regulated apoptosis in ovaries and uteri of gilts.Conclusions: The present results indicated that feeding diet contaminated with ZEA and DON simultaneously(596.86 μg/kg + 796 μg/kg) had detrimental effects on growth performance, plasma immune function and reproductive status of gilts. And MBA could reduce the negative impacts of these two toxins, believed as a promising feed additive for mitigating toxicosis of ZEA and DON at low levels in gilts.  相似文献   
86.
Rangelands cover about 82% of the arid area of Morocco. It is generally acknowledged that these areas are threatened by desertification. Monitoring desertification requires accurate knowledge about the current status of rangeland degradation. Remote sensing is widely used to assess changes in land cover, but its use in arid rangelands has limitations because of spectral confusion among various types of land cover. The objective of this study was to assess the severity and spatial extent of rangeland degradation in the high plateaus of eastern Morocco, using a knowledge‐based approach combining remote sensing and ancillary data. This approach relies on analyzing datasets derived from Landsat TM satellite imagery, lithology, bioclimatic data and field measurements. The level of rangeland degradation was assessed using indicators such as vegetation parameters, grazing levels and cultivation intensity, which provided a high level of accuracy for mapping and monitoring the degradation of the arid rangelands. The results showed that the total area of degraded rangeland in the high plateaus of eastern Morocco is about 17,417 km2, accounting for 48% in the studied area. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
87.
The possible relationships between the main emulsion components (namely, Arabic gum, xanthan gum, and orange oil) and the physicochemical properties of orange beverage emulsion were evaluated by using response surface methodology. The physicochemical emulsion property variables considered as response variables were emulsion stability, viscosity, fluid behavior, zeta-potential, and electrophoretic mobility. The independent variables had the most and least significant ( p < 0.05) effect on viscosity and zeta-potential, respectively. The quadratic effect of orange oil and Arabic gum, the interaction effect of Arabic gum and xanthan gum, and the main effect of Arabic gum were the most significant ( p < 0.05) effects on turbidity loss rate, viscosity, viscosity ratio, and mobility, respectively. The main effect of Arabic gum was found to be significant ( p < 0.05) in all response variables except for turbidity loss rate. The nonlinear regression equations were significantly ( p < 0.05) fitted for all response variables with high R (2) values (>0.86), which had no indication of lack of fit. The results indicated that a combined level of 10.78% (w/w) Arabic gum, 0.56% (w/w) xanthan gum, and 15.27% (w/w) orange oil was predicted to provide the overall optimum region in terms of physicochemical properties studied. No significant ( p > 0.05) difference between the experimental and the predicted values confirmed the adequacy of response surface equations.  相似文献   
88.
Late blight (LB), caused by the oomycete Phytophtohra infestans, is one of the most destructive diseases of tomato (Solanum lycopersicum) and other Solanaceae species. Current disease control and prevention strategies are not sufficient to control the disease in tomato. Recent germplasm screening experiments led to the identification of a new source of resistance (PI 270443) in the tomato wild species S. pimpinellifolium. This study was conducted to identify genomic regions associated with LB resistance in this accession. A large F2 population (n = 986) derived from a cross between PI 270443 and a LB-susceptible tomato breeding line (NCEBR-2) was screened for LB resistance using a highly aggressive isolate of P. infestans. Twenty-five of the most resistant and 29 of the most susceptible, but surviving F2 individuals were identified based on disease evaluations conducted in the F2 and F3 progeny populations. The selected individuals were genotyped with 153 DNA markers located across the 12 tomato chromosomes. A selective genotyping approach led to the identification of two genomic regions on tomato chromosomes 1 and 10 associated with LB resistance in PI 270443. Identification of two genomic regions associated with resistance was consistent with a previous estimate of the number of LB resistance genes in this accession. Research is currently underway to fine map the two resistance genes and incorporate them into new tomato breeding lines and hybrid cultivars.  相似文献   
89.
A reliable and rapid pathogen detection protocol that utilizes loop-mediated isothermal amplification (LAMP) was developed for detection of Erwinia amylovora, the casual agent of fire blight. The six LAMP primers applied were derived from the highly conserved fragment of the chromosomally amsH gene. Despite the proposed LAMP as well as nested PCR presenting equal values of sensitivity (2?×?101?CFU/ml or more) for pure cultures, as compared with conventional PCR (2?×?103?CFU/ml), both methods were together superior. The specificity assay also showed that the LAMP protocol is species-specific for detection of E. amylovora even in inter-species analysis. Meanwhile, when all 208 naturally infected samples were examined, the specificity value of LAMP was 84%, while conventional and nested PCR could detect only 59% and 73% of the whole collection. Significantly, an independent behaviour versus host plant as well as each strain origin was also observed regarding the current LAMP method as well as other two PCR-based methods. All the results, overall, indicated that the LAMP offers an interesting novel and convenient assay format for the quick and specific chromosomal detection and diagnostic tool of recognition of E. amylovora and therefore presents an alternative to PCR-based assays.  相似文献   
90.
Background:As critical regulators, lncRNAs have attracted attention from researchers for diagnostic, prognostic, and therapeutic purposes in human carcinogenesis via interfering with mRNAs such as EZH2. Nevertheless, the potent roles and molecular mechanisms of these RNAs in CRC are not clearly known. Methods:In this study, the tissue expressions of lncRNA MINCR and EZH2 mRNA between colorectal tumors and polyps were compared with the adjacent normal tissues collected from 114 Iranian patients, using real-time PCR method. Furthermore, the correlation of the expression levels of MINCR and EZH2 with other clinical parameters was evaluated. Results:The significant overexpression of MINCR and EZH2 were observed in the CRC tissues compared to control tissues (p < 0.0001). This observation confirmed the association of these expression enhancements with the pathological stage of CRC patients. Conclusion:Our findings revealed that the expression of MINCR significantly alters during CRC development, and it can be identified as a potential biomarker for the detection of CRC.Key Words: Colorectal cancer, EZH2, Long non-coding RNA  相似文献   
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