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101.
102.
Due to the diminished use of growth-promoting antibiotics in the European Union, Clostridium perfringens induced necrotic enteritis and subclinical disease have become important threats to poultry health. A study was set up to genotypically and phenotypically characterise C. perfringens isolates from poultry flocks with different health status. Animals from healthy flocks were sampled by cloacal swabs, while intestinal and liver samples of animals suffering from necrotic enteritis were analysed. A total of 27 isolates was obtained from 23 broiler flocks without clinical problems and 36 isolates were obtained from 8 flocks with clinical problems. Using PFGE typing, high genetic diversity was detected between isolates from different flocks. Isolates derived from flocks where disease outbreaks occurred were clonal within each flock, but each flock harboured a different clone. All isolates were of toxin type A. Isolates from 5 out of 35 PFGE types carried the cpb2 gene, encoding the beta2 toxin, and isolates from 2 out of 35 PFGE types harboured the cpe gene, encoding the enterotoxin. In vitro alpha toxin production for all isolates was quantified by enzyme-linked immunosorbent assay. It was shown that in vitro alpha toxin production of C. perfringens isolates from diseased flocks was not higher than in vitro alpha toxin production from isolates derived from healthy flocks.  相似文献   
103.
Diploid wheat (Triticum monococcum L, AmAm) is an ideal material for induced mutations which can be easily characterized and transferred to polyploid wheats. The EMS-induced brittle culm mutants, brc1, brc2, and brc3 used in the present investigation, were isolated from T. monococcum. All the brittle mutants had brittle roots, leaves, leaf sheaths, culms, and spikes, and were also susceptible to lodging. The mutants had 47–57% reduced α-cellulose in the secondary cell walls than that of T. monococcum indicating that all of them had defective synthesis of cellulose. All the mutants were monogenic recessive. Bulk segregation analysis of the mutants, using Am genome anchored SSR markers in their F 2 populations with T. boeoticum, located the mutants, brc1, brc2, and brc3 on chromosome 6A, 3A, and 1A of T. monococcum, respectively. Molecular analysis of the putatively linked markers showed that brc1 mapped on chromosome 6AS between Xbarc37 and Xbarc113 markers, brc2 on chromosome 3AL between Xcfd62 and Xcfa2170 markers whereas brc3 mapped on chromosome 1AL between Xgwm135 and Xwmc470 markers. Isolation and mapping of three different brittle culm mutants in wheat for the first time shows that there might be many more genes in wheat which affect synthesis and deposition of cellulose.  相似文献   
104.
Recently, brassinosteroids (BRs) have emerged as a new group of growth promoting phytohormones. 28-homobrassinolide (HBR) is one of the several brassinosteroids, the role of which in enhancing growth, productivity and quality of plants, via improving various physiological processes, has been established both under stress and normal conditions. Out of a large number of essential oil bearing plants, mint (Mentha arvensis L.) constitutes the most important source of therapeutic agents used in the alternative systems of medicine. The mint plant has marvelous medicinal and aromatic values. In view of enhancing yield and quality of this medicinally important plant, a pot experiment was conducted under natural conditions of net house. The study was aimed at exploring the effect of four concentrations of HBR (10?0, 10?8, 10?7 and 10?6 M) on the performance of mint with regard to physiological attributes, herbage yield, content and yield of essential oil, and active constituents at 100 and 120 days after planting. The foliar application of HBR enhanced physiological attributes, herbage yield and the yield and content of most of the active constituents (menthol, L-methone, isomenthone and menthyl acetate) of mint at both the stages, with 10?7 M concentration proving the best. However, the next higher concentration of HBR (10?6 M) exhibited no further increase in the values of the attributes studied. Rather, 10?6 M was slightly inferior to 10?7 M concentration; but it always proved significantly better than the control.  相似文献   
105.
A Boer goat breeding farm with 800 heads of breeder females, 50 breeder males, and 400 growing goats of various ages in Sabah, Malaysia was selected to study the effect of implementing herd health program. This included vaccination program against pneumonic mannheimiosis; fecal monitoring for helminthiasis, coccidiosis, and colibacillosis; and introduction of modified feeding regime comprised of day-time grazing and feeding of cut grass and supplemented feed. The herd health program was implemented in September 2007 and the impact was observed on body weight gains, body scoring, and annual mortality among adults and kids. It was found that implementation of herd health program significantly (p < 0.05) increased the average body weight gains in both adults and kids from 1.8 g per kid and 0.6 g per adult in 2006 to 3.7 g per kid and 2.2 g per adult in 2008. The percentage of adults with body scoring of <3 was significantly (p < 0.05) reduced from 82.3% in 2006 to 77.6% in 2007 and 4% in 2008. Similarly, the annual mortality rate was significantly (p < 0.05) reduced from 6.5% among kids and 58.2% among adults in 2006 to 12.1% among kids and 10.4% among adults in 2007, and to 9.1% among kids and 1.1% among adults in 2008. Therefore, it was concluded that implementation of herd health program significantly improved the survival and performance of goats.  相似文献   
106.
The present study was conducted to screen Kashmir valley sheep with history of prolificacy for the presence of FecB mutation. Forced polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) and single strand conformation polymorphism (SSCP) techniques were employed to detect any polymorphism present in bone morphogenetic protein receptor type 1B (BMPR1B) gene. Further, it was aimed at introgressing the FecB mutation into nonprolific noncarrier sheep. A 140-bp fragment of BMPR1B gene was amplified from isolated genomic DNA and subjected to forced RFLP with restriction enzyme AvaII. Three different RFLP patterns were identified. SSCP analysis showed one-to-one correspondence with RFLP patterns. Sequencing of the samples showing different patterns revealed that the wild (+) and mutant (B) alleles were different by a single nucleotide substitution in the form of A109G from wild to mutant allele. It led to change in amino acid from Glutamine (Q) to Arginine (R) from wild to mutant allele. The mutation was only detected in NARI-Suwarna and their crosses; all Kashmir valley sheep with prolific history lacked it. The + allele was abundant in the studied population. The FecB mutation was introgressed in nonprolific noncarrier sheep by crossing ewes with NARI-Suwarna rams possessing the mutation. First generation crossing produced heterozygous (B+) progeny. Some of the F1 heterozygous ewes gave birth to twins when mated to unrelated NARI-Suwarna rams. It showed that FecB mutation was successfully expressing in those crosses.  相似文献   
107.
A survey was carried in North Khorasan Province, Iran in 2010–2011, designed to identify Theileria spp. infections of both sheep and ticks. The tick species were also examined. Ninety sheep from different flocks were clinically examined, and blood samples and ixodid ticks were collected. Light microscopy of blood smears revealed Theileria spp. infection in 37 (41.1 %), while 74 (82.2 %) of blood samples were positive using semi-nested PCR. Theileria ovis, Theileria lestoquardi, and mixed infection were detected in 63/90 (70 %), 5/90 (5.5 %), and 6/90 (6.6 %) of samples, respectively. Of the 434 ticks that were collected, the most prevalent species was Rhipicephalus turanicus (69.3 %) followed by Hyalomma marginatum turanicum (18.4 %), Dermacentor marginatus (6.4 %), and Rhipicephalus bursa (5.7 %). The ticks were separated into 42 tick pools, and the salivary glands were dissected out in 0.85 % (w/v) saline under a stereomicroscope and examined using semi-nested PCR. Three pools of H. marginatum turanicum salivary glands were infected with T. ovis and T. lestoquardi, and one pool of R. turanicus was infected with T. ovis. Based on these results, it is concluded that the prevalence of T. ovis is higher than T. lestoquardi and that H. marginatum turanicum and R. turanicus are likely vectors of T. lestoquardi and T. ovis in this area.  相似文献   
108.
The anthelmintic potentials of the aqueous and methanol extracts of Euphorbia helioscopia were investigated. In folklore medicine, E. helioscopia (Euphorbiaceae) is used in the treatment of various gastrointestinal ailments and diseases. A worm motility inhibition (WMI) assay and egg hatch assay (EHA) were used for in vitro assessment, and a faecal egg count reduction (FECR) assay was used for an in vivo study. The in vitro study revealed anthelmintic effects of crude methanolic extracts of E. helioscopia on live Haemonchus contortus worms as evident from their paralysis and/or death at 8h after exposure, different concentrations (12.5mgml(-1), 25mgml(-1) and 50mgml(-1)) of aqueous and methanolic extracts were used against H. contortus which exhibited dose-dependent anthelmintic effects on H. contortus. Aqueous and methanolic extracts of aerial parts (stem, leaves and flowers) of E. helioscopia were found to have very low percent inhibitory egg hatching as compared to levamisole. It is concluded that the entire plant of E. helioscopia possesses significant anthelmintic activity and could be a potential alternative for treating cases of helminth infections in ruminants.  相似文献   
109.
Various plants are well known for their insecticidal activity and their use was maintained for millennia throughout all the agricultural regions of the world. In a current context, the use of Botanical insecticides represents one of the best alternatives to chemicals for the development of environmental-friendly strategies for stored grain pest control. Datura alba Nees is a plant found extensively in the warmer regions of the world and it is used as a medicinal plant. This study aims to assess the contact toxicity and the trans-generational effect of D.?alba leaf extract (DLE) against two important insect pests on stored rice, Trogoderma granarium and Sitophilus oryzae, under laboratory conditions. Filter papers were soaked in three DLE concentration solutions and in two control treatments: water and acetone. The survivor specimens (F0) were transferred to a new untreated feeding substrate and the population build up of the two following generations (F1 and F2) were counted after 30 and 60?days, respectively. The highest DLE concentration (2.5?%) induced the significantly highest mortality with 33.5 and 45?% mortality in T.?granarium and S.?oryzae after 7?days of exposure, respectively. The DLE long-term effect toward both tested species was also proved by the high demographic decrease in the F2 generations, when compared to control groups. This study is the first step toward establishing a scientific basis for the effective application of D.?alba plant materials as biorational tools to control stored grain pests.  相似文献   
110.
Glanders is a highly infectious and zoonotic disease of solipeds caused by Burkholderia mallei. Progressive loss of efficiency and fatal outcome resulted in massive economic losses, which forced veterinary authorities throughout the world to implement disease control measures; these measures included mass testing using the complement fixation test and/or malleinization, and the culling of positives. This led to the eradication of glanders from Western Europe and North America in the 1950s. However, in the last decade, the number of outbreaks in Asia and South America increased steadily, and glanders regained the status of a re-emerging transboundary disease. Pakistan has been an endemic country for the past 120 years, but concise data on the presence of disease are not available. A total of 533 serum samples were collected from draught equines, a suspected risk group for glanders, from various districts of Punjab in Pakistan. The complement fixation test and the highly sensitive Western blot technique were used for serodiagnosis. No animal (horse, mule, and donkey) was found to be positive for infection. Glanders seems to be restricted to remote, sporadic pockets of endemicity and may cause outbreaks after being introduced into naive populations by (asymptomatic) shedders.  相似文献   
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