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81.
Otsamo Antti Ådjers Göran Hadi Tjuk Samito Kuusipalo Jussi Vuokko Risto 《New Forests》1997,14(2):127-143
Survival and growth of 83 tree species were tested in three separate species elimination trials on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia. The trial layout was randomized complete blocks design with 6–8 replications of 5-tree line plots. At the age of two years exotics, like several Acacia species (A. mangium, A. crassicarpa, A. auriculiformis, A. cincinnata, A. leptocarpa), as well as Gmelina arborea, Paraserianthes falcataria and Cassia siamea had survival rates of 90–100%, crown width of 3–6 m and mean height of 5–8 m. Among the most promising local species were Anthocephalus chinensis, Peronema canescens and Parkia roxburghii but their growth was inferior compared to exotics. Eucalypts and pines were not among the highest ranking trees and cannot be recommended for initial grassland reforestation. At the age of 7–8 years the same species were still dominating, but increasing mortality of several species was observed. Especially Acacia crassicarpa and A. cincinnata of the exotics were affected, and indigenous Anthocephalus chinensis almost perished. Since fast early growth is necessary in first rotation reforestation of grasslands, fast growing exotic species provide a reliable basis for further activities. Final performance of reforestation species has to be confirmed in stand-level experiments and pilot plantations. Intensive work on integrating local tree species in reforestation of grasslands in the long run is recommended. 相似文献
82.
Mahdi Golshan Hamid R. Habibi Sayyed Mohammad Hadi Alavi 《Fish physiology and biochemistry》2016,42(4):1157-1165
Vinclozolin (VZ) is a pesticide that acts as an anti-androgen to impair reproduction in mammals. However, VZ-induced disruption of reproduction is largely unknown in fish. In the present study, we have established a combination exposure in which adult goldfish were exposed to VZ (30 and 100 μg/L), anti-androgen flutamide (Flu, 300 μg/L), and androgen testosterone (T, 1 μg/L) to better understand effects of VZ on reproductive endocrine system. mRNA levels of kisspeptin (kiss-1 and kiss-2) and its receptor (gpr54), salmon gonadotropin-releasing hormone (gnrh3) and androgen receptor (ar) in the mid-brain, and luteinizing hormone receptor (lhr) in the testis were analyzed and compared with those of control following 10 days of exposure. kiss-1 mRNA level was increased in goldfish exposed to 100 µg/L VZ and to Flu, while kiss-2 mRNA level was increased following exposure to Flu and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. gpr54 mRNA level was increased in goldfish exposed to Flu and to combination of 30 µg/L VZ with Flu and 100 µg/L VZ with T. gnrh3 mRNA level was increased in goldfish exposed to 100 µg/L VZ, to Flu, and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. The mid-brain ar mRNA level was increased in goldfish exposed to Flu and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. Testicular lhr mRNA level was increased in goldfish exposed to Flu and to combination of 30 µg/L VZ with Flu. These results suggest that VZ and Flu are capable of interfering with kisspeptin and GnRH systems to alter pituitary and testicular horonal functions in adult goldfish and the brain ar mediates VZ-induced disruption of androgen production. 相似文献
83.
Chemical composition and osmolality of seminal fluid of Acipenser persicus; their physiological relationship with sperm motility 总被引:2,自引:0,他引:2
Sayyed Mohammad Hadi Alavi Jacky Cosson Mahmoud Karami Hossein Abdolhay & Bagher Mojazi Amiri 《Aquaculture Research》2004,35(13):1238-1243
Determination of semen quality is necessary to understand the basic biochemical processes occurring during motility of sperm and during fertilization to evaluate the reproductive ability of different fish species and to create an optimal environment for storage of spermatozoa; in this regard less information is available for Acipenseridae compared with Cyprinidae and Salmonidae. The aim of the present study is to determine chemical composition and osmolality of seminal fluid and their relationship with sperm motility in Acipenser persicus. The results obtained show that sodium (Na+), chloride (Cl?) and potassium (K+) were predominant ions in the seminal plasma and the average of osmolality of seminal plasma was 82.56 mOsm kg?1. The higher chemical contents and osmolality compared with other sturgeon species reveal species‐specific characteristics and high secretory activity of spermatic duct in A. persicus. Significant positive correlations were observed between osmolality‐Cl?, Na+‐osmolality and Na+–Cl? (P<0.05, P<0.001 and P<0.05 respectively). But statistically significant correlation was not observed between seminal plasma parameters and sperm motility. Probably, the Na+ and Cl? are the main electrolytes playing a major role in maintaining the osmolality of the seminal plasma and the viability of the spermatozoa in vivo. 相似文献
84.
Nasser Vesal Mohammadrahim Ahmadi Mehrzad Foroud Hadi Imani 《Veterinary anaesthesia and analgesia》2013,40(3):328-332
ObjectiveTo evaluate the anti-nociceptive effects of lidocaine, lidocaine-bupivacaine combination or bupivacaine following caudal epidural administration in cows undergoing reproductive procedures.Study designBlinded, randomized experimental study.AnimalsThirty seven healthy Holstein cows (mean weight ± SD, 633 ± 41 kg).MethodsAnimals were allocated randomly to receive one of four treatments: group LID, 0.2 mg kg?1 lidocaine 2%; group LID-BUP, lidocaine-bupivacaine mixture in a 1:1 volume ratio (0.1 mg kg?1 and 0.025 mg kg?1, respectively); group BUP-LD, 0.05 mg kg?1 bupivacaine 0.5%; and group BUP-HD, 0.06 mg kg?1 bupivacaine 0.5%. The onset and duration of perineal anti-nociception were determined using superficial and deep pin pricks and the number of cows with complete perineal anti-nociception was recorded. Parameters were compared using anova followed by Duncan's test where relevant.ResultsMean ± SD time to onset of anti-nociception following epidural administration of BUP-LD was significantly longer than for LID-BUP (p < 0.05). The duration (in minutes) of perineal anti-nociception was significantly longer following epidural administration of BUP-HD (247 ± 31) versus LID-BUP (181 ± 33) and LID (127 ± 25) minutes respectively. The % of cows with complete anti-nociception was increased in the group treated with BUP-HD compared to BUP-LD. Severe ataxia or recumbency did not occur in any groups.Conclusions and clinical relevanceEpidurally administered bupivacaine, at a dose of 0.06 mg kg?1, may provide satisfactory caudal epidural anti-nociception for longer-duration obstetric and surgical procedures. 相似文献
85.
Saeed Sadigh-Eteghad Hadi khayat-Nuri Siavash Ghavami Dariush Shanebandi 《Research in veterinary science》2011,91(1):82-85
This research investigated the effects of levamisole and Echinacea purpurea (EP), separately and together on the immune response of the rat as a laboratory model. In this experiment, 40 male Wistar rats were obtained and divided into four groups (n = 10). These groups received normal saline (10 mg/kg), EP (500 mg/kg), levamisole (2 mg/kg) and EP (500 mg/kg) with levamisole (2 mg/kg) as oral gavages every day for a period of 4 weeks, respectively. After obtaining blood samples (at the end of each week), haematocrit (HCT), differential and total white blood cell (WBC) counts, phagocyte activity (number), total protein, albumin and globulins levels of samples were obtained. The results of the study showed that the gamma globulin level, WBC, neutrophil and monocyte counts and phagocyte activity increased significantly in comparison with normal saline group during the study. According to the results, each of the mentioned agents had a stimulant effect on the immune system separately and together on rats. In the group that received EP and levamisole simultaneously, these effects were synergistically increased. These compounds, by increasing the mentioned factors, will probably affect the immune system. 相似文献
86.
This investigation was conducted to evaluate the comparative productive performances and effect of some environmental factors
on wool characteristics of Arkharmerino × Ghezel (Ar × Gh) and Arkharmerino × Moghani (Ar × Mo) crossbreed sheep. The mid-side
fleece samples taken from animals during 2 years (2007–2008) were analyzed. Each sample was measured for average fiber diameter,
fiber diameter variability, staple length, proportion of medullated fiber, proportion of kemp, and comfort factor. The comparative
values for these fleece characteristics in F3 generation Ar × Gh were 28.78 ± 0.48 μm, 36.84 ± 1.16%, 11.94 ± 0.35 cm, 7.07 ± 0.93%, 1.02 ± 0.23%, and 68.93%, respectively;
while those traits were 29.79 ± 0.43 μm, 41.86 ± 1.16%, 11.96 ± 0.37 cm, 8.13 ± 1.06%, 2.71 ± 0.45%, and 63.33 ± 3.66% for
Ar × Mo, respectively. The effects of genotype, sex, birth type, and year of birth were analyzed. Genotype had a significant
(P < 0.01) effect on average fiber diameter and proportion of kemp, and Ar × Gh crossbreeds had lower diameter with less proportion
of kemp. The two differences in fiber characteristics that were attributable to sex were fiber diameter variability and proportion
of medullated fiber, and females had higher measure than males for both traits. Statistical analysis showed that crossbreeding
with Arkharmerino generally had positive effects on the fleece favored to be used in the hand woven authentic carpet production. 相似文献
87.
Alexandra Zieritz Leonardo Jainih John Pfeiffer Khairul Adha A. Rahim Hari Prayogo Muhammad Sofwan Anwari Arman Hadi Fikri Farah Diba Hussein Taha Zohrah Sulaiman Elsa Froufe Manuel Lopes-Lima 《水产资源保护:海洋与淡水生态系统》2021,31(11):3169-3183
- Most of the Bornean endemic freshwater mussel (Unionida) species known to date have not been recorded by science for the past 50 years or more, owing to a lack of research effort and presumed population losses.
- This study assessed current patterns and recent changes in the diversity and distribution of freshwater mussels in north-eastern Borneo. Physical surveys and interviews were conducted at 24 sites, and anecdotal evidence for current or historical presence of mussels was collected for a further 13 sites.
- Native species, i.e. Schepmania sp. and Khairuloconcha sahanae gen. & sp. nov., were only found in one small stream of the Kinabatangan River basin within the Gomantong Forest Reserve, whereas the non-native Sinanodonta cf. woodiana was common across the study area.
- Molecular phylogenetics (five genes) of the native taxa, including comparative material from West Kalimantan and Sarawak, revealed: (i) the presence of a new genus with two new, rare species: Khairuloconcha lunbawangorum sp. nov. in the Limbang River basin and K. sahanae in the Kinabatangan River basin; (ii) that Khairuloconcha and Ctenodesma form the Bornean endemic tribe Ctenodesmini trib. nov.; and (iii) that Schepmania represents another Bornean endemic tribe Schepmaniini trib. nov.
- Both Khairuloconcha gen. nov. species are known from a single stream each and are apparently restricted to forest stream habitats where they occur at very low densities. Schepmania appears to have a severely contracted range in the Kinabatangan and adjacent basins. We urgently call for full protection of the currently known sites of K. lunbawangorum and K. sahanae, and development of an action plan to save the Bornean freshwater mussel fauna.
88.
Potato is a staple food crop and the most important agricultural commodity, which critically affects food security and economic stability in Hamadan Province, Iran. Ex-ante sustainability appraisal of new cropping systems and their comparisons with conventional systems can increase the efficiencies of innovations and changes within the production process. This study aimed to explore the sustainability levels of potato cropping systems in Hamadan Province, Iran. To this end, DEXi methodology was developed for the sustainability assessment of the cropping systems. For assessing the three dimensions of environmental, economic, and social sustainability in the four systems of traditional potato system (TPS), Quasi-industrial potato system (QIPS), industrial potato system (IPS), and government-promoted potato system (GPPS), five groups of features were utilized: (1) irrigation method; (2) seed placement; (3) farm machinery use; (4) agrochemical use; and (5) rotation. The impact assessments of the cropping systems were based on two, three, and two groups of ecological, social, and economic indicators, respectively. Employment, supply chain, protection, operational difficulty, productivity, profitability, input use, and biodiversity resulted in 21 basic indicators and 13 aggregated indicators, by which the cropping systems were described. The results revealed that GPPS with distinctive economic and social profiles could have a better overall sustainability despite the fact that some indicators like biodiversity could be negatively affected. Finally, three strategies were recommended for the sustainability of GPPS as follows: biodiversity enhancement, input substitution, and integrated water management. 相似文献
89.
Development of latex agglutination test with recombinant NcSAG1 for the rapid detection of antibodies to Neospora caninum in cattle 总被引:1,自引:0,他引:1
Moraveji M Hosseini A Moghaddar N Namavari MM Eskandari MH 《Veterinary parasitology》2012,189(2-4):211-217
Neospora caninum, an apicomplexan protozoan parasite, is recognized as a major cause of abortion in cattle. Surface antigen 1 of N. caninum (NcSAG1) is an important immunodominant candidate for the development of a diagnostic reagent for neosporosis. The present study describes the development and evaluation of a latex agglutination test (LAT) with recombinant NcSAG1 (rNcSAG1) for the detection of antibodies to N. caninum in cattle. The rNcSAG1 gene was cloned in pET-28a and protein was expressed in Escherichia coli BL21 (DE3). Carboxylated latex particles were coated with rNcSAG1 and the degree of agreement between LAT and a commercial enzyme-linked immunosorbent assay (iscomELISA) was evaluated by using of 164 serum samples. Twenty-two (13.4%) and 23 (14.0%) of samples were positive for antibodies to N. caninum by LAT and ELISA respectively. Eighteen of 23 ELISA-positive samples were positive according to the LAT and a substantial agreement (κ=0.77) was found between the results of LAT and ELISA. The results indicated that the LAT with rNcSAG1 would be a rapid, simple, relatively inexpensive and suitable diagnostic test for detection of specific antibodies in N. caninum infection under field conditions. Improvement in purification of rNcSAG1 can reduce probable false positive reactions and so increase the degree of agreement between the LAT and ELISA. 相似文献
90.
Biodiversity and prevalence of parasites of domestic pigeons (Columba livia domestica) in a selected semiarid zone of South Khorasan, Iran 总被引:1,自引:0,他引:1
Radfar MH Asl EN Seghinsara HR Dehaghi MM Fathi S 《Tropical animal health and production》2012,44(2):225-229
Five species of nematodes and cestodes were collected from alimentary canals of pigeons: the nematodes were two species: Ascaridia colombae (16.66%) and Hadjelia truncata (1.96%), while the cestodes were Cotugnia digonopora (13.79%), Raillietina magninumida (18.62%) and Raillietina achinobothridia (32.35%); fecal examination revealed: Eimeria spp. (40.19%) and Cryptosporidium oocysts (2.94%); and blood smears showed: Haemoproteus cloumbae (47/05%); in mouth, throat and larynx: Trichomonans gallinae (57.84%); four species of ectoparasites were collected from feathers and subcutaneous nodules as follows: feathers: Pseudolynchia canariensis (63.72%), Columbicola columbae (79.41%), Menopen gallinea (44.11%); subcutaneous nodules: Laminosioptes cysticola (1.96%). From the parasitic fauna identified in this study, it is imperative to institute an integrated parasitic control
through constant changing of litter, regular use of antihelminthics, anticoccidials and dusting of birds with pesticides. 相似文献