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排序方式: 共有748条查询结果,搜索用时 15 毫秒
1.
Fifty faecal samples from diarrheic calves between 1 and 6 months old were collected per rectum from 5 farms around Petaling District in Selangor, Malaysia for Cryptosporidium species detection and genotyping investigation. Oocysts were purified using sedimentation and gradient centrifugation, then examined by immunofluorescence assay (IFAT). Genomic DNA was extracted from all samples and nested PCR was performed to amplify the SSU rRNA gene. Eighteen samples (36%) were positive for Cryptosporidium species by PCR. The sequence and phylogenetic analysis of 14 isolates indicated that Cryptosporidium parvum was most common (11 isolates) followed by Cryptosporidium deer-like genotype (3 isolates). The present work reports the first data on Cryptosporidium genotyping from cattle in Malaysia. 相似文献
2.
A survey of ovine schistosomiasis was carried out in a Schistosoma bovis enzootic area in the central Sudan. Three hundred Desert sheep, representing different age groups, were screened for infection, using Pitchford's faecal egg counting technique. No infection was detected in animals under one year old, but from the age of 18 months onward, the prevalence increased progressively from around 20 per cent to 60 per cent in six-year-old sheep, and this was accompanied by an increase in infection intensity, as determined by faecal egg counts. These findings, which suggest that these sheep did not develop an effective resistance to schistosomiasis, contrasted with those previously recorded in cattle from the same locality, studied in the same year. 相似文献
3.
Toghyani M Toghyani M Shahryar HA Zamanizad M 《Tropical animal health and production》2011,43(6):1183-1189
The objective of this study was to evaluate the effects of two methods of early-age water restriction on performance, some
immune responses, serum metabolites, and prevalence of leg weakness in broiler chicks. One-hundred-eighty-seven-day-old chicks
(Ross 308) were allocated to three treatments with four replicates based on a completely randomized design. Treatments included
the control group, where birds had free access to water, and water-restricted groups, where access to water was limited to
three 2-h periods (WRT1) or a 12-h period (WRT2) per day from days 7 to 17. Chicks in the control group were significantly
heavier (P < 0.05) at 17 and 46 days of age compared to the restricted birds. In the WRT2 group, feed intake decreased significantly
over the 17- to 28-day period while feed conversion ratio was poorer during water restriction (P < 0.05). Antibody titers against Newcastle and SRBC were higher (P < 0.05) for chicks with ad libitum access to water. Birds in the restricted groups exhibited a higher heterophil to lymphocyte
ratio compared to the control group (P < 0.05). The treatments had no significant impact on serum metabolites including protein, triglyceride, total cholesterol,
high-density lipoprotein and low-density lipoprotein cholesterols, calcium, and phosphorus concentrations. Walking ability,
tibial dyschondroplasia, foot pad, hock burn, and valgus/varus angulation were not significantly influenced by water restriction.
In conclusion, the current results indicate that early-age water restriction negatively influenced productive traits and immunological
responses of broiler chicks and failed to have any favorable impacts on leg health. 相似文献
4.
5.
Saber Jelokhani-Niaraki Majid Esmaelizad Morteza Daliri Rasoul Vaez-Torshizi Morteza Kamalzadeh Mohsen Lotfi 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(3):243-247
The A Iran 05 foot-and-mouth disease virus (FMDV) subtype was detected in Iran during 2005 and has proven to be highly virulent. This study was undertaken to focus on molecular and phylogenetic analysis of 3A and 3B coding-regions in the A Iran 05 field isolate. To assess the genetic relatedness of A Iran 05 isolate the nucleotide and predicted amino acid sequences of the 3AB region of type A FMDV isolates were compared with twenty previously described type A FMDV isolates. The phylogenetic tree based on the 672 bp 3AB gene sequences of type A FMDV from thirteen different locations clustered them into five distinct lineages. The A Iran 05 isolate clustered in lineage A along with four type A variants and was closely matched with viruses isolated in Turkey and Pakistan during 2005~2006. The number of protein sequence differences exhibited by each of the isolates revealed that A Iran 05 isolate contains three amino acid substitutions at positions 47 and 119 of 3A and 27 of the 3B coding region. The nucleotide identity between A Iran 05 and the other four isolates of lineage A was estimated to be 98%. 相似文献
6.
The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This present work evaluated the efficacy of ethyl acetate, acetone, and methanol dried leaf and seed extracts of five medicinal plants were tested in vitro ovicidal and larvicidal activities on Haemonchus contortus. The in vitro assay was based on egg hatch assay (EHA) and larval development assay (LDA), all plant extracts were evaluated at five concentrations 50, 25, 12.5, 6.25 and 3.13 mg/ml. The leaf and seed ethyl acetate, acetone and methanol of Annona squamosa, Eclipta prostrata, Solanum torvum, Terminalia chebula, and Catharanthus roseus extracts were showed complete inhibition (100%) at the maximum concentration tested (50 mg/ml). The overall findings of the present study have shown that our experimental plant extracts contain possible anthelmintic compounds. 相似文献
7.
Govindasamy Rajakumar Abdul Abdul Rahuman Kanayairam Velayutham Jeyaraman Ramyadevi Kadarkaraithangam Jeyasubramanian Arumugam Marikani Gandhi Elango Chinnaperumal Kamaraj Thirunavukkarasu Santhoshkumar Sampath Marimuthu Abdul Abduz Zahir Asokan Bagavan Chidambaram Jayaseelan Arivarasan Vishnu Kirthi Moorthy Iyappan Chinnadurai Siva 《Veterinary parasitology》2013,191(3-4):332-339
The present study was on assessment of the anti-parasitic activities of nickel nanoparticles (Ni NPs) against the larvae of cattle ticks Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum (a.) anatolicum (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, Culex quinquefasciatus and Culex gelidus (Diptera: Culicidae). The metallic Ni NPs were synthesized by polyol process from Ni-hydrazine as precursor and Tween 80 as both the medium and the stabilizing reagent. The synthesized Ni NPs were characterized by Fourier transform infrared (FTIR) spectroscopy analysis which indicated the presence of Ni NPs. Synthesized Ni NPs showed the X-ray diffraction (XRD) peaks at 42.76°, 53.40°, and 76.44°, identified as 1 1 1, 2 2 0, and 2 0 0 reflections, respectively. Scanning electron microscopy (SEM) analysis of the synthesized Ni NPs clearly showed that the Ni NPs were spherical in shape with an average size of 150 nm. The Ni NPs showed maximum activity against the larvae of R. (B.) microplus, H. a. anatolicum, A. subpictus, C. quinquefasciatus and C. gelidus with LC50 values of 10.17, 10.81, 4.93, 5.56 and 4.94 mg/L; r2 values of 0.990, 0.993, 0.992, 0.950 and 0.988 and the efficacy of Ni-hydrazine complexes showed the LC50 values of 20.35, 22.72, 8.29, 9.69 and 7.83 mg/L; r2 values of 0.988, 0.986, 0.989, 0.944 and 0.978, respectively. The findings revealed that synthesized Ni NPs possess excellent larvicidal parasitic activity. To the best of our knowledge, this is the first report on larvicidal activity of blood feeding parasites using synthesized Ni NPs. 相似文献
8.
Masoud Selk Ghaffari DVM PhD Mehdi Marjani DVM PhD Majid Masoudifard DVM PhD 《Journal of Veterinary Cardiology》2009,11(1):67-69
A 3-year-old crossbreed male dog was presented with a history of blunt facial trauma. Skull radiographs showed right zygomatic arch fracture. An electrocardiogram revealed bradycardia, first-degree atrioventricular block and QT prolongation. Standard biochemical profile including electrolytes was normal. Atropine response test (0.04 mg/kg intravenously) restored normal sinus rhythm at a rate of 140 bpm with normal QT and PR intervals. This observation is consistent with oculocardiac reflex secondary to zygomatic arch fracture. 相似文献
9.
Afshin Raoofi DVM DVSc Seyed Hossein Mardjanmehr DVM PhD Majid Masoudifard DVM DVSc Farajollah Adibhashemi DVM DVSc Peyman Asadian DVM PhD 《Journal of Equine Veterinary Science》2006,26(12):588-591
A 4-year-old crossbred Thoroughbred mare was referred to the University of Tehran Veterinary Medical Teaching Hospital for evaluation of a mass in the pelvic cavity. The mare had been partially anorectic and pyrexic. On clinical examination, the mare was thin and depressed, with body temperature of 38°C, a pulse rate of 38 beats/minute, and a respiratory rate of 10 breaths/minute. Palpation per rectum revealed a large, smooth and tense mass in the anterior part of the pelvic cavity. Ultrasound examination confirmed the presence of a soft tissue mass with a thick wall. The inner surface of the mass had a villous-like appearance. The stroma of the mass was mottled, with accumulation of speckled and hypoechoic to slightly hyperechoic fluid. Hormone assays revealed low serum concentration of testosterone. Serum progesterone concentration indicated that active luteal tissue and serum estradiol concentration was 24 pg/ml. On histological examination, the sections from the tumor were composed of oval- or spindle-shaped cells loosely arranged in diffuse sheets or irregularly interlacing fascicles. On the basis of these histological findings, the large tumor mass of the left ovary was considered to be a thecoma. To our knowledge, the details of the clinical, ultrasonographic, endocrinologic, and histologic findings of this tumor in the mare have not been described in the veterinary literature. 相似文献
10.
Sara Oveissi Abdul Rahman Omar Khatijah Yusoff Fatemeh Jahanshiri Sharifah Syed Hassan 《Comparative immunology, microbiology and infectious diseases》2010,33(6):491-503
The H5 gene of avian influenza virus (AIV) strain A/chicken/Malaysia/5744/2004(H5N1) was cloned into pcDNA3.1 vector, and Esat-6 gene of Mycobacterium tuberculosis was fused into downstream of the H5 gene as a genetic adjuvant for DNA vaccine candidates. The antibody level against AIV was measured using enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HI) test. Sera obtained from specific-pathogen-free chickens immunized with pcDNA3.1/H5 and pcDNA3.1/H5/Esat-6 demonstrated antibody responses as early as 2 weeks after the first immunization. Furthermore, the overall HI antibody titer in chickens immunized with pcDNA3.1/H5/Esat-6 was higher compared to the chickens immunized with pcDNA3.1/H5 (p < 0.05). The results suggested that Esat-6 gene of M. tuberculosis is a potential genetic adjuvant for the development of effective H5 DNA vaccine in chickens. 相似文献