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11.
In the present study, we examined the mortality rate, egg production, and clinical signs of quail experimentally infected with a field isolate of A/Chicken/Iran/339/02 (H9N2) avian influenza virus obtained from an infected commercial layer farm with severe morbidity and mortality. A total of 120 quail at 14 days old were randomly divided into four groups of vaccinated (B and C) and unvaccinated (A and D) birds. Vaccination was done on days 20 and 32, and viral inoculation of birds in groups C and D was then carried out on day 43. For evaluation of viral transmission, at 24 hr postinoculation additional unvaccinated birds were placed in direct contact with challenged birds. All the birds were evaluated for clinical signs, egg production, antibody production, viral titration in lung homogenates, and viral transmission following inoculation. All unvaccinated-challenged birds were infected and showed clinical signs, whereas the infection rate along with clinical signs of vaccinated-challenged birds reached 30%-40%. Although vaccination induced high antibody titers, reduction in food and water consumption was evident in this vaccinated-challenged group compared with the unchallenged control group. These results could indicate that inactivated vaccine did not fully prevent the infection, although it was capable of protecting birds against clinical signs and significantly decreased viral titers in lungs after intranasal challenge.  相似文献   
12.
  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   
13.
A biological assay was carried out to evaluate the impact of dietary tryptophan (TRP) in aflatoxin B1‐contaminated diets (AFB1‐D) on performance, blood parameters, immunity, meat quality and microbial populations of intestine in Japanese quails. Six experimental diets were formulated to include two levels of dietary TRP; 2.9 (moderate high: MH‐TRP) and 4.9 g/kg (excess: Ex‐TRP); and three levels of AFB1 (0.0, 2.5, and 5.0 mg/kg). Each experimental diet was fed to the one of the six groups of birds from 7 to 35 days of age in a completely randomized design with 2 × 3 factorial arrangement. Decrease in feed intake, body weight gain and gain:feed in birds fed 5.0 mg/kg AFB1‐D was restored to the control level by 4.9 g TRP/kg of the diet. The hepatic enzymes in blood were elevated in quails fed on AFB1‐D but attenuated by 4.9 g TRP/kg of the diet (Ex‐TRP; p ≤ .01). High serum uric acid in birds challenged with AFB1 significantly decreased by Ex‐TRP (p ≤ .01). The skin thickness to 2,4‐dinitro‐1‐chlorobenzene challenge suppressed by AFB1 but increased by Ex‐TRP diet (p ≤ .02). The AFB1 increased the malondialdehyde in meat, whereas TRP efficiently diminished malondialdehyde production (p ≤ .01). The greatest drip loss and pH in meat were observed in the birds fed 5.0 mg/kg AFB1‐D but Ex‐TRP augmented the adverse effects of AFB1 (p ≤ .01). The Ex‐TRP reduced the total microbial and Escherichia coli counts (p ≤ .01). The adverse effect of AFB1 on ileal Lactic acid bacteria was completely prevented by Ex‐TRP (p ≤ .03). This study showed that tryptophan supplementation could be considered as a powerful nutritional tool to ameliorate the adverse effects of AFB1 in growing quails.  相似文献   
14.
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   
15.
The objective of this study was to determine the effects of different levels of crude protein (CP) and dietary electrolyte balance (DEB) on productive performance, egg quality, and blood biochemical parameters of laying hens reared during hot summer months. The average minimum and maximum room temperatures recorded from 32 to 42 weeks of age were 27.2 and 36.5 °C, respectively, with relative humidity ranging from 48 to 56 %. A total of 144 Lohmann LSL-Lite laying hens were assigned to each of four dietary treatments with six replicate cages of six birds. The treatments were as follows: CP 15.4 % + DEB 165 mEq/kg (group 1), CP 15.4 % + DEB 250 mEq/kg (group 2), CP 13.9 % + DEB 165 mEq/kg (group 3), and CP 13.9 % + DEB 250 mEq/kg (group 4). In groups 3 and 4, feed conversion ratio and blood uric acid were decreased (P?<?0.05); but the plasma triglyceride level was increased (P?<?0.05) compared to groups 1 and 2. Low-CP diet with DEB 250 (group 4) also induced significant increases of average egg production and eggshell thickness compared to group 1. Blood pH, Na+, and HCO3 ? values were also higher (P?<?0.05) in groups 2 and 4 than in the other groups. These results indicate that, under tropical conditions, using a DEB of 250 mEq/kg achieves a correction of the lay-induced metabolic acidosis and induces a positive effect on eggshell quality when the hens were fed low-protein diet.  相似文献   
16.
This experiment was carried out to investigate the potential probiotic properties of Bacillus subtilis and suitable methods of administration to the commercial feed in juvenile Macrobrachium rosenbergii (de Man) from 25 August to 25 November 2008. Putative Bacillus subtilis bacterium isolated from juvenile M. rosenbergii intestine was added to commercial prawn feed as a probiotic. Five types of diets were prepared by mixing B. subtilis at level of 108 cells g?1 with commercial feed using different methods consisting mixing, soaking, spraying and bathing. After 60?days, the prawns fed diets at soaking method treated group, showed a higher mean weight gain (2.09) or 328.84% increase in growth over control. There were significant differences (P?<?0.05) in weight gain, feed intake and FCR among soaking method and other treated and control groups. There was significant difference (P?<?0.05) in survival among treated and control groups, but no significant difference (P?>?0.05) in water quality and biochemical composition among treated and control groups. Clearly, B. subtilis-treated diets appeared to enhance growth and survival of juveniles M. rosenbergii. It was concluded that the tested strain may be a promising probiotic for M. rosenbergii under soaking method of administration to the prawn commercial feed.  相似文献   
17.

Background  

Restless Legs Syndrome (RLS) is a common neurological movement disorder characterized by symptoms that follow a circadian pattern. Night and rotating shift work schedules exert adverse effects on functions of the human body by disturbing circadian rhythms, and they are known to cause sleep disturbances and insomnia. In this paper, we investigate the possible association between shift work and RLS.  相似文献   
18.
The objective of this study was to evaluate if treatment of equine chorionic gonadotrophin (eCG)-superovulated Sanjabi ewes with repeated administration of human chorionic gonadotropin (hCG) would increase the number of normal corpus luteum (CL) and serum progesterone concentrations and decrease the number of persistent follicles. The superovulated ewes were divided into four groups on day 0 (day of sponge removal); the ewes were treated by an intramuscular administration of 500?IU hCG on day 0 (Group I: n?=?10), on days 0 and 1 (Group II: n?=?10), or on days 0, 1, and 2 (Group III: n?=?10) and no treatment for control group (n?=?10). Blood samples were collected on days 0, 1, 2, 5, and 8 (day of slaughter), and serum progesterone concentrations were determined. According to progesterone concentrations, 50 (4/8) and 0?% of the ewes underwent premature luteal regression in the control group and the hCG groups, respectively. There were more CLs in Group III than in Group II and the control group. Ewes treated with hCG had a greater number of normal-looking CL. CL diameter was significantly greater in Group II and Group III than other groups. Total CL weight was significantly (P?<?0.05) higher in Group III than in Group I and the control group. Number of persistent follicle and persistent follicle diameter were lower in control group compared to the other groups. Eight days after sponge removal, serum progesterone concentration was significantly higher in Group III than in Group I and the control group. The present results indicate that repeated administration of hCG supported CL formation, increased serum progesterone concentration, and prevented premature luteal regression in eCG-superovulated Sanjabi ewes.  相似文献   
19.
Pearl millet grain could be considered as an alternative feed ingredient for poultry. In a 12 wks experiment, the performance of laying hens fed diets containing pearl millet were compared with those fed diets containing corn. Maize grain was replaced by pearl millet on an equal-weight at either 0, 25, 50, 75 or 100%. Results showed that use of 25, 50 and 75% of pearl millet in place of maize in the diet resulted in similar (P > 0.05) hen-day egg production, egg mass, egg weight, feed intake and feed conversion ratio to those of control group. Totally replacement of maize grain with pearl millet significantly (P < 0.05) reduced all production parameters. Egg quality parameters did not affect by using pearl millet in the diet. These results showed that maize grain can be replaced by pearl millet up to 75% in the diets of laying hens without any adverse effect on hen performance or egg quality.  相似文献   
20.
International Aquatic Research - Longtail tuna (Thunnus tonggol) is one of the most economically important tuna species in Iranian waters of Persian Gulf and Oman Sea. Some population dynamics...  相似文献   
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