Reactivity of anti-Nipah virus monoclonal antibodies to formalin-fixed, paraffin-embedded lung tissues from experimental Nipah and Hendra virus infections

The immunohistochemical reactivity of seven clones of mouse monoclonal antibodies raised to Nipah virus antigens were investigated using formalin-fixed, paraffin embedded porcine and equine lung tissues from experimental Nipah and Hendra virus infection, respectively. Either microwave irradiation or enzymatic digestion effectively unmasked the viral antigens in formalin-fixed, paraffin-embedded tissue sections. Four clones showed positive reaction to both Nipah virus-infected porcine lung tissue and Hendra virus-infected equine lung tissue. Two clones (11F6 and 13A5) reacted with Nipah virus-infected porcine lung tissue, but not with Hendra virus-infected equine lung tissue. These Nipah virus-specific monoclonal antibodies may therefore be useful for immunohistological diagnosis of Nipah virus infection and for further research on Nipah virus pathogenesis.     

Semi‐synthetic diet versus diet using natural ingredients—Comparative study in female Golden Syrian hamsters

Semi‐synthetic diets (SSD) are recommended and are widely used to carry out experiments in rodents. However, in our experiments planned to carry out generation studies in female Golden Syrian hamsters using semi‐synthetic diets, it was observed that the hamsters did not conceive as a result of decreased food intake. In this paper, we present the effects of both semi‐synthetic diets and natural source diets (NSD) on food intake, body weight and reproductive performance of this species. Four‐week‐old female hamsters were equally divided into 3 groups and initially acclimatized for 2 weeks on natural chow diet (NCD). Thereafter, they were fed either control diet, high fat diet (HFD) or low protein diet (LPD) based on semi‐synthetic/natural source ingredients until 12 weeks. Daily food intake and weekly body weights were monitored. Hamsters were kept for mating for about 2 weeks from 10th week onwards, during which the pregnancy confirmation test was done using standard vaginal smear examination. In all the groups fed SSD, the food intake was very poor, hamsters lost body weight and did not conceive, thus preventing us from carrying out further experiments. Hamsters fed NCD/NSD ingested more than twice as much as hamsters fed SSD (7–8 g/day/hamster against 3 g/day/hamster on average respectively). Based on the results of the current research, we conclude that the routinely used semi‐synthetic diet is not suitable for carrying out studies in female hamsters. We suggest that scientists must also consider the unusual biological characteristics of a given species besides other biological factors. It is therefore critical to select appropriate biological models and diets that provide optimal sensitivity and specificity to accomplish the research objectives.     

Impact of restricting feed and probiotic supplementation on growth performance,mortality and carcass traits of meat‐type quails

The objective of this study was to evaluate the effects of quantitative feed restriction, along with dietary supplementation with a probiotic blend (Protexin) as a natural growth promoter, on the performance, water consumption, mortality rate and carcass traits of meat‐type quails. A total of 250 1‐day unsexed quails were randomly allocated to five equal groups in a completely randomized design. The first group (A) fed a basal diet without any restriction (24 hr/day); the second group (B1) fed the basal diet for 20 hr/day; the third group (B2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 20 hr/day; the fourth group (C1) fed the basal diet for 16 hr/day; and the fifth group (C2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 16 hr/day. Birds were fed ad‐libitum from 0–14 days of age, and then the feed restriction regimes started from 14 till 28 days of age. Results showed that quails in the control‐group consumed more feed and water than the other treatment groups (p < .01), however their body weights did not differ (p > .05) compared with the other treated groups. The best feed conversion values were achieved in quails supplemented with probiotic blend (B2 and C2) in comparison with the other groups (p < .01). Feeding probiotic had a positive effect on bird health which reduced the mortality rate. Further, mortality rate was significantly reduced (p < .05) by feed restriction, with or without probiotic supplementation. No carcass parameters were significantly affected (p > .05) by treatments. Our results show that quail could be reared under a feed restriction system, for 4–8 hr daily, along with dietary supplementation of probiotic as growth promoter for better growth performance.     

Molecular mapping of leaf rust resistance genes in the wheat line Yu 356-9

The Chinese wheat line Yu 356-9 exhibits a high level of resistance to leaf rust. In order to decipher the genetic base of resistance in Yu 356-9, gene postulation, inheritance analyses, and chromosome linkage mapping were carried out. Gene postulation completed using 15 leaf rust pathotypes and 36 isogenic lines indicated that Yu 356-9 was resistant to all pathotypes tested. F1 and F2 plants from the cross Yu 356-9(resistant)/Zhengzhou 5389(susceptible) were tested with leaf rust pathotype "FHNQ" in the greenhouse. Results indicated a 3:1 segregation ratio, indicative of the presence of a single dominant leaf rust resistance gene in Yu 356-9 which was temporarily designated as Lr Yu. Bulk segregant analysis and molecular marker assays were used to map Lr Yu. Five simple sequence repeat(SSR) markers on chromosome 2BS were found closely linked to Lr Yu. Among these markers, Xwmc770 is the most closely linked, with a genetic distance of 5.7 c M.     

Chromosome pairing and fertility of interspecific hybrids between Trifolium repens L. and T. occidentale Coombe

Trifolium occidentale is a diploid wild relative with the potential to improve the drought and salt tolerances of white clover (Trifolium repens). Previous work has shown that it is possible to efficiently produce large T. repens × T. occidentale breeding populations using colchicine‐doubled (4×) T. occidentale. For effective introgression (backcross) breeding, it is also essential that interspecific chromosome pairing and recombination occur. In this study, it was apparent that chromosome pairing was occurring not only between T. occidentale and T. repens subgenomes, but also between the ancestral subgenomes of T. repens. Thus, interspecific hybridization has the potential for major genome recombination and opens the way for introgression of traits from T. occidentale into white clover.     

Effect of emamectin benzoate on life history traits and relative fitness of Spodoptera litura (Lepidoptera: Noctuidae)

Emamectin benzoate, a semisynthetic bioinsecticide, has been used frequently for the management of lepidopteran pests of cotton worldwide. To assess the resistance risk and design strategy for resistance management, life history traits were established for emamectin benzoate-resistant, unselected and susceptible S. litura strains based on the laboratory observations. Bioassay results showed that the emamectin benzoate-selected strain developed a resistance ratio of 911-fold compared with that of the susceptible strain. The emamectin-selected strain had a relative fitness of 0.37 and lower prepupal and pupal weights, prolonged larval duration and development time, lower fecundity and hatchability compared with the susceptible strain. Mean population growth rates, such as intrinsic rate of population increase and biotic potential, were lower for the emamectin-selected strain compared with the susceptible strain. Development of resistance can cost considerable fitness for the emamectin-selected strain. The present study provided useful information for determining potential management strategies to overcome development of resistance.     

An analysis of threats to endangered animal taxa in California's freshwater systems

相似文献   

Mapping of quantitative trait loci controlling cotton leaf curl disease resistance in upland cotton

Cotton leaf curl disease (CLCuD) is a major threat to cotton production in Asia and Africa. Using marker-assisted breeding can be the best sustainable approach to tackle CLCuD. Identification of new QTLs in the indigenous cotton germplasm is necessary to combat CLCuD. The current study was designed to construct a genetic linkage map of bi-parental F2:F3 populations developed from highly tolerant MNH-886 and highly susceptible S-12 cotton cultivars. One hundred seven CLCuD-associated simple sequence repeat (SSR) marker alleles were identified as polymorphic and three new QTLs were found on chromosomes C11, C19 and C21. Two QTLs on chromosomes C11 and C19 were detected in both F2 and F3 populations in the region flanked by SSR markers CIR316 and BNL4094, and BNL285 and BNL3348, respectively. Whereas, one QTL on chromosome C21 was detected in the region flanked by SSR markers JESPR158 and JESPR135 in both F2 and F3 generations. The CLCuD-associated QTLs identified in this study can help fine-tune the molecular mapping of the QTLs on the cotton genome against CLCuD.