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1.
The beneficial effects of different lighting programmes on the incidence of ascites was investigated in an experiment with 360 three-day-old male broiler chickens. At 3 days of age, chicks were randomly divided over three rooms in a high-altitude farm, 2000 m above sea level. During days 14 to 28 ambient temperature decreased during the night but the minimum temperature did not descend below 15 degrees C. In the first room the continuous lighting schedule (CL, 23L:1D) was maintained and in the second room an intermittent lighting schedule (IL, 1L:3D), repeated six times daily, was imposed from 3 days of age. In the third room, an increasing photoperiod schedule (IP, 4 to 14 days, 6L:18D; 15 to 21 days, 10L:14D; 22 to 28 days, 14L:10D; 29 to 35 days, 18L:6D; 36 to 42 days, 23L:1D) was provided. Mortality associated with right ventricular failure and ascites was numerically lower in birds reared under the IL and IP schedules compared to birds reared under the CL schedule, which can be attributed to the temporary reduction in relative growth and feed intake in IL and IP birds. It was concluded that the beneficial effect of lighting schedules could be due to a reduced metabolic rate as a consequence of the altered growth trajectory, as also reflected in the lower haematocrit and plasma T3 levels of IL and IP birds compared to CL birds. 相似文献
2.
A Najafi MH Najafi Z Zanganeh M Sharafi F Martinez‐Pastor H Adeldust 《Reproduction in domestic animals》2014,49(6):934-940
A soybean lecithin‐based extender supplemented with hyaluronic acid (HA) was assayed for effectiveness to improve the quality of frozen–thawed ram semen. HA has not been tested yet in an extender containing soybean lecithin for freezing ram semen. Thus, the aim of this study was to analyse the effects of soybean lecithin at 1% or 1.5% along with HA at 0, 0.5 and 1 mg ml‐1 in a Tris‐based extender on the motion characteristics, membrane integrity (HOST), viability, GSH peroxidase (GSH‐PX) activity, lipid peroxidation and acrosomal status after freezing–thawing. Semen was collected from four Mehraban rams during the breeding season and frozen in the six lecithin×HA extenders. The extender containing 1.5% lecithin supplemented with no HA yielded higher total motility (52.5%±1.6), viability (55.8%±1.6) and membrane integrity (44.5%±1.7), but the effects of the lecithin concentration did not reach signification. Linearity‐related parameters, ALH, BCF, lipid peroxidation, GSH‐PX activity, morphology and acrosomal status were not affected by the extender composition. In general, adding HA significantly decreased sperm velocity (1 mg ml‐1 HA), total motility (only with 1.5% lecithin), viability (1 mg ml‐1 HA for 1% lecithin; both concentrations for 1.5% lecithin) and membrane integrity. In conclusion, adding HA to the freezing extender supplemented with soybean lecithin failed to improve quality‐related variables in ram semen. Increasing the lecithin content could have a positive effect, but further studies are needed. 相似文献
3.
JI Yun HJ Park MH Park MS Kim JH Choi E Lee SP Gong JM Lim ST Lee 《Reproduction in domestic animals》2014,49(5):705-710
Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long‐term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC‐specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome‐shaped morphology, AP activity and expression of SSC‐specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats. 相似文献
4.
van Putten MH 《Science (New York, N.Y.)》1999,284(5411):115-118
The coalescence of a neutron star and a black hole in a binary system is believed to form a torus around a Kerr black hole. A similarly shaped magnetosphere then results from the remnant magnetic field of the neutron star. In the strong-field case, it contains a cavity for plasma waves located between the barrier of the gravitational potential and the surrounding torus. This cavity may be unstable to superradiance of electromagnetic waves. Superradiant amplification of such waves, initially excited by turbulence in the torus, should inflate into a bubble in a time as short as approximately 0.75 (1 percent/&cjs3539;epsilon&cjs3539;2)(M/7M middle dot in circle) seconds approximately 0.15 to 1.5 seconds, assuming an efficiency &cjs3539;epsilon&cjs3539;2 = 0.5 to 5 percent and a mass M = 7M middle dot in circle. These bubbles may burst and repeat, of possible relevance to intermittency in cosmological gamma-ray bursts. The model predicts gamma-ray bursts to be anticorrelated with their gravitational wave emissions. 相似文献
5.
The effect of melanocortin (Mc3 and Mc4) antagonists on serotonin-induced food and water intake of broiler cockerels 总被引：3，自引：0，他引：3
Morteza Zendehdel Farshid Hamidi Vahab Babapour Kasra Mokhtarpouriani Ramin Mazaheri Nezhad Fard 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(3):229-234
The current study was designed to examine the effects of intracerebroventricular injections of SHU9119 [a nonselective melanocortin receptor (McR) antagonist] and MCL0020 (a selective McR antagonist) on the serotonin-induced eating and drinking responses of broiler cockerels deprived of food for 24 h (FD24). For Experiment 1, the chickens were intracerebroventricularly injected with 2.5, 5, and 10 µg serotonin. In Experiment 2, the chickens received 2 nmol SHU9119 before being injected with 10 µg serotonin. For Experiment 3, the chickens were given 10 µg serotonin after receiving 2 nmol MCL0020, and the level of food and water intake was determined 3 h post-injection. Results of this study showed that serotonin decreased food intake but increased water intake among the FD24 broiler cockerels and that these effects occurred in a dose-dependent manner. The inhibitory effect of serotonin on food intake was significantly attenuated by pretreatment with SHU9119 and MCL0020. However, the stimulatory effect of serotonin on water intake was not altered by this pretreatment. These results suggest that serotonin hypophagia and hyperdipsia were mediated by different mechanisms in the central nervous system, and that serotonin required downstream activation of McRs to promote hypophagia but not hyperdipsia in the FD24 chickens. 相似文献
6.
Sajjad Hosseinzadeh Monfared Mohammad Matinizadeh Anoushirvan Shirvany Ghavamedin Zahedi Amiri Reza Mousavi Fard Fariba Rostami 《林业研究》2013,24(2):391-395
Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma (ICP). We investigated the uptaking ability of lead (Pb) and cadmium (Cd) by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index (MAI). Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves (2.21) and F. rotundifolia had the highest MAI value for shoots (2.4). 相似文献
7.
Saeid R. Nourollahi Fard Masoud Asghari Fatemeh Nouri 《Tropical animal health and production》2009,41(8):1633-1636
The parasite of genus Sarcocystis is one of the most commonly found parasite in domestic animals worldwide. Some species of Sarcocystis cause important economic loss when causing clinical and sub clinical disease. The aim of this study was to determine the
prevalence of Sarcocystis in slaughtered Cattle in Kerman, Iran. The prevalence of Sarcocystis spp. infection was investigated in 480 cattle, slaughtered from May 2005 to February 2006 in the Kerman, Iran using naked
eye examination for macroscopic Sarcocysts, and peptic digestion, muscle squash, squeezing methods for microscopic types.
Muscles from heart, tongue, and esophagus, cervical and abdominal muscles of 480 slaughtered cattle were examined for Sarcocystis cysts. The prevalence of microscopic Sarcocystis cysts in cattle was detected in 100% and there was no macroscopic cyst in examined cattle. 相似文献
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9.
Malmasi A Mosallanejad B Mohebali M Sharifian Fard M Taheri M 《Zoonoses and public health》2009,56(2):102-104
This work aimed to evaluate the effects of preventive oral Clindamycin in cats infected with Toxoplasma gondii. Twelve short hair cats were divided into two groups (group 1 and group 2). No titres of T. gondii antibodies were detected in these cats before the experiment. The animals from group 1 were infected with tissue cysts of T. gondii and group 2 were infected and treated with Clindamycin (20 mg/kg/day). The infection was done with almost 40-50 tissue cysts for each cat on day 0. The cats from group 2 were treated with Clindamycin by oral rout for 24 days (from day -3 to day 21). At day 45, the groups 1 and 2 were divided into two subgroups with three animals each. Subgroups 1A and 2A were immunosuppressed with dexamethasone (1 mg/kg/day) for30 days and subgroups 1B and 2B were not immunosuppressed. Faecal exam looking for oocyst shedding was made by 30 days after T. gondii infection, and for 30 days after immunosuppression. All kittens from group 1 shedding oocysts after infection, while animals from group 2 did not shed. After immunosuppression period, all animals from group 1A re-shed oocysts and animals from group 2A remained without shed. However, 2 (66.6%) of the kittens from subgroup 2B shed oocysts 19-20 days after re-challenge. Based on this preliminary study, Clindamycin had a complete inhibitory effect on shedding of oocysts by cats, even under severe immunosuppression, which is a new finding not reported elsewhere. 相似文献
10.
1. A 6-week study was conducted to investigate the effects of phytase and hydroalcoholic extract of Withania somnifera root (WS) on productive performance and bone mineralisation of laying hens in the late phase of production. 2. Diets were arranged factorially (3?×?2?×?2) and consisted of a positive control with adequate Ca (4·37%) and nonphytate P (NPP; 0·39%) and a negative control diet with Ca (4·06%) and NPP (0·36 %); three concentrations of Withania somnifera (0, 65 and 130?mg/kg diet); and two concentrations of microbial phytase (0 and 300 U/kg diet). 3. A total of 144 72-week-old Hy-Line W36 laying hens were randomly assigned to the 12 treatment groups. Each treatment was replicated 4 times (4 x 3 hens). Egg production and egg weight were recorded daily, while feed intake and egg quality traits were recorded every two weeks. Bone quality traits were evaluated at the end of experiment. 4. Withania somnifera supplementation increased egg production and lowered egg weight only in the second two weeks of the experiment. Addition of phytase significantly depressed specific gravity of the eggs for the entire experiment period. No dietary treatment effects were observed on egg shell thickness and yolk weight. 5. Withania somnifera at 130?mg/kg did not affect feed intake. The hens fed on the positive control diet had higher albumen weight than the negative control diet in the second two-week period. Supplementation of the positive control diet with 65?mg/kg Withania somnifera in the absence of phytase significantly improved shell weight compared with the negative control (5·779 vs. 5·273?g respectively). 6. Supplementing Withania somnifera significantly improved Ca and P retention in tibia bone. In addition, an increase in tibia bone P was observed with phytase supplementation. There were significant interactions between Withania somnifera content and phytase for tibia bone Ca and P. 7. The results of this experiment indicated that dietary Withania somnifera has beneficial effects on tibia bone Ca and P content, and phytase improved tibia bone P retention without adverse effects on productive performance. 相似文献