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1.
The effects of biofloc technology (BFT) were tested on growth performance, water quality, haemolymph parameters and hepatopancreas histology with and without BFT for the speckled shrimp. In this study, eight different experimental groups were formed (four BFT and four control groups) to measure the effects of different feeding rates on compensatory growth of speckled shrimp. BFT treatments were performed with zero water exchange and planned as BFT1: gradually feed decreasing group 4, 2 and 1% bw, BFT2: 4% bw, BFT3: 2‐days feed with 4% bw, 1‐day fasted, and BFT4: 1‐day feed with 4% bw, 1‐day fasted. In control treatment, the same trial groups were constituted for comparing with BFT at a 50% daily water exchange: C1 (gradually feed decreasing group: 4%, 2% and 1% bw), C2 (4% bw), C3 (2‐days feed with 4% bw, 1‐day fasted), C4 (1‐day feed with 4% bw, 1‐day fasted). There were significant differences between BFT and C groups in terms of some water quality (p < 0.05). In general, BFT had an effect on haemocyte profile. At the histological examination, there were no pathological findings in both BFT and control groups. The growth parameters of speckled shrimps in BFT groups, as well as the whole body crude protein ratios and crude ash contents, were higher than the control group (p < 0.05). The results confirmed that biofloc utilization increased with decreasing feeding.  相似文献   
2.
The genomic region spanning the two ribosomal RNA internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene was cloned and sequenced from sixteen Theileria isolates. Each Theileria species possessed ITS1 and ITS2 of unique size(s) and species specific nucleotide sequences. Varying degrees of ITS1 and ITS2 intra- and inter-species sequence polymorphism were found among ruminant Theileria species. The spacers were most polymorphic in the agent of tropical theileriosis, Theileria annulata, and were more conserved in two benign species, Theileria buffeli and Theileria sergenti Chitose. Phylogenetic analysis of the rDNA ITS1-5.8S rRNA gene-ITS2 region clearly separated each taxon, placing them in three clusters. One held T. annulata, Theileria parva, and Theileria mutans, with the latter two most closely related. The second held T. sergenti Ikeda, T. sergenti Chitose, and T. buffeli, with the latter two most closely related. The third cluster held the Theileria ovis isolates.  相似文献   
3.
4.
The heat shock protein 70 (hsp70) genes of Babesia gibsoni, B. canis canis, B. canis vogeli, and B. canis rossi isolated from infected dogs were cloned by polymerase chain reaction (PCR) and sequenced. In the nucleotide sequence and the predicted amino acid sequence of the gene, the parasites were very similar to each other. The nucleotide sequences of the hsp70 gene had more variety than those of 18S nuclear subunit ribosomal DNA (18S rDNA). A phylogenetic analysis of these sequences and comparisons with sequences from other Babesia and Theileria species revealed that all canine babesial isolates analyzed in the present study were closely related to each other and formed one cluster. Additionally, a phylogenetic analysis of Babesia and Theileria species showed that these parasites could be divided into three groups: group A including canine babesial isolates, B. divergens, B. odocoilei, B. bovis, B. caballi, and B. ovis; group B including Theileria annulata, T. orientalis, and T. cervi; and group C including B. microti and B. rodhaini. These results suggested that a phylogenetic analysis of the hsp70 gene sequence might be helpful in classifying Babesia and Theileria species, and that canine babesial isolates might be closely related to each other, indicating their evolution from the same ancestry.  相似文献   
5.
Ostriches lack meibom glands, but have small lacrimal glands ventral to the lateral canthus, with ductules that open into the inside of the lower eyelid. Chalazion is a chronic granulomatous inflammation of the meibom glands that may develop from blockage of the ductules into the conjunctiva. A 2-year-old female ostrich presented with chronic granulomatous conjunctivitis, with clinical and histopathologic findings similar to chalazion of other species. The granulomatous dacryoadenitic mass was excised and no recurrence occurred at 4 months. This is the first case of chronic granulomatous conjunctivitis reported in the ostrich.  相似文献   
6.
The prevalence of Dirofilaria immitis infection was evaluated in stray dogs of Erzurum, Turkey. A total of 123 whole-blood and 93 sera samples were collected from stray dogs older than 6 months were lived in animal shelter. The PCR and direct microscopic examinations were used for the detection of microfilaria and indirect-ELISA was performed for the detection of anti-D. immitis antibodies. The prevalence of D. immitis in the canine population was 8.1% by PCR, 2.1% by ELISA. In addition, microfilaria burdens of Dirofilaria sp. was 4.8% by direct blood smear examination. There was a statistical difference (P=0.05) in the prevalence between males (10.5%) and females (2.3%) by direct blood smear examination. Similarly there was a statistical difference (P<0.05) in the prevalence between males (15.8%) and females (4.7%) by PCR. Dogs belonging to the 0.5-1 years old group showed the highest prevalence than 2-4 ages group with three tests. Among the 93 samples screened by the ELISA, two samples were positive for the D. immitis antibodies. Both positive dogs with ELISA were females.  相似文献   
7.
Summary

Environmental stresses such as high temperature and high salinity are known to cause oxidative stress in plants by enhancing the generation of reactive oxygen species (ROS), which have a strong impact on plant development. Mitochondria constitute one of the major sources of ROS in roots. Recently, it has been shown in mammalian systems that methylene blue (MB) at very low concentrations can attenuate mitochondrial ageing by scavenging ROS. In the present study, we tested whether MB could be used to protect tomato (Lycopersicon esculentum L.) seedlings against the harmful effects of high salinity and high root temperature. Tomato seedlings were grown hydroponically and were subjected to two abiotic stresses: high salinity (150 mM NaCl) in the nutrient medium, or high root temperature (35ºC) for 14 d. These stress treatments were applied with or without the addition of 10–8 M MB. The results showed that, under normal conditions, MB enhanced root and shoot growth, increased root respiration, decreased root H2O2 and malonyldialdehyde (MDA) concentrations, and enhanced root superoxide dismutase (SOD) activity. Both high salinity and high root temperature stress impaired root and shoot growth, and caused an enhancement of root oxidative stress. MB had a significant protective effect against both abiotic stresses and restored the levels of oxidative stress-related components (i.e., H2O2 and MDA) in root and leaf tissues almost to normal levels. It is hypothesised that MB could confer its protective effect not only through interactions with root mitochondria, but also via additional cellular targets in the root.  相似文献   
8.
PCR-based detection of Theileria ovis in Rhipicephalus bursa adult ticks   总被引:1,自引:0,他引:1  
Tick-borne diseases in ruminants are common in tropical and subtropical regions and lead to meat and milk production losses. In this study, polymerase chain reaction (PCR) was used to assess the presence of Theileria ovis in Rhipicephalus bursa ticks. We have demonstrated that the PCR enabled detection of T. ovis in field isolates of R. bursa collected from naturally infested sheep and goats in eastern Turkey. The sampling was done in spring season (between May and June 2004). A total of 420 R. bursa were collected and randomly selected 192 number of them (97 female and 95 male) were dissected. Primers specific for 520 bp fragments small subunit ribosomal RNA (ssu rRNA) gene of T. ovis amplified products from 37 of the 192 (19.27%) samples. The parasite was detected in 17 (17.52%) female and in 20 (21.05%) male ticks. Two T. ovis amplicons from the tick samples were purified and sequenced. The resulting sequences were identical to the nucleotide sequence of the Turkish sheep strain of T. ovis. These results showed that R. bursa might play an important role in the field as a natural vector of T. ovis.  相似文献   
9.
A survey of Theileria parasites in cattle in eastern Turkey was carried out using specific polymerase chain reaction. A total of 252 blood samples were collected from clinically healthy cattle between June and July 2004. Of 252 blood samples examined, 41 (16%) were positive for piroplasms by microscopy, whereas 114 (45%) were positive for the presence of at least one species of Theileria by PCR. The percentages of positive animals for Theileria annulata and benign Theileria species (Theileria sergenti/buffeli/orientalis) were 39% (99/252) and 7% (18/252), respectively. By allele-specific PCR examination of 18 field isolates which were positive for benign Theileria parasites, 8 samples were only amplified by B-type specific primers and 10 samples were amplified by both of the B and C-type specific primers, indicating a mixed infection with B and C-type of the parasite. None of the field isolates was amplified by I-type specific primers. Three samples were co-infected with T. annulata and benign Theileria parasites. Two of them which were infected with B-type parasite were also infected with T. annulata, the other sample which was infected both of B and C-type parasites was also infected with T. annulata. A total of 724 ixodid ticks were collected from the cattle. Hyalomma anatolicum anatolicum was the dominant species with 32% (230/724) in the region. H. a. excavatum, Boophylus annulatus and Rhipicephalus bursa represented 25% (183/724), 19% (140/724) and 15% (112/724) of the total number of ticks, respectively. R. sanguineus was the minor species and represented 8% (59/724) of the tick population.  相似文献   
10.
Larvae of Metapenaeus monoceros (Fabricius) at protozoea 1 (PZ1) stage were stocked in 2‐L glass flasks to investigate the effects of various salinities (25, 30, 35, 40, 45, 50 and 55 ppt) on growth and survival until the post‐larval (PL) stages. The PZ larvae were not able to tolerate a sudden salinity drop of over 10 ppt. Yet, an abrupt salinity increase of over 10 or even 15 ppt did not cause mortality. The PZ larvae were successfully acclimated to different test salinities at a rate of 4 ppt h?1. The larvae displayed better tolerance to high rather than low salinities. The lowest and highest critical salinities appeared to be 22 and 55 ppt respectively. Taking into account survival, growth and development results, the optimal salinity for the larval culture of M. monoceros inhabiting the Eastern Mediterranean was 40 ppt. At this salinity, the PZ1 larvae were successfully cultured until PL1 stage within 11 days with 68% survival on a feeding regime of Tetraselmis chuii Kylin (Butcher) (20 cells μ L?1), Chaetoceros calcitrans Paulsen (50 cells μ L?1), Isochrysis galbana Parke (30 cells μL?1) and five newly hatched Artemia nauplii mL?1 from M1 onwards at 28 °C.  相似文献   
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