Efficacy of Vaccination Against Streptococcus iniae During Artificial Spawning of the Red-Tail Black Shark (Epalzeorhynchos bicolor,fam. Cyprinidae)

Artificial spawning may precipitate high mortalities of red-tail black shark (Epalzeorhynchos bicolor) broodstock from Streptococcus iniae infection. Two vaccine formulations (aluminum or oil adjuvant) were evaluated for effectiveness. Fish (mean weight 21.2 ± 5.7 g) were harvested, acclimatized, and vaccinated by intracoelomic injection. After 21 days, fish were moved to a biosecure laboratory and, one day later, simultaneously spawned and challenged by bath or by intracoelomic injection with S. iniae. Both formulations increased relative% survival (RPS) in unspawned (RPS [formulation]: 80 [aluminum]; 54 [oil]) and spawned fish (87–95 [aluminum]; 73–75 [oil]), suggesting that vaccination increases survival of red-tail black shark broodstock after spawning.     

Greenhouse production of potato (Solanum tuberosum L. cv. Désirée) seed tubers using in vitro plantlets and rooted cuttings in large propagation beds

Summary Seed tuber production fromin vitro potato plantlets and cuttings was conducted in large propagation beds in a greenhouse. Propagules of wholein vitro plantlets (WIP), plantlets with apical (ACR) and lateral (LCR) cuttings removed, the rooted apical cuttings (RAC) and rooted lateral cuttings (RLC) were planted at three densities of 25, 49 and 100 plants per m². The plantlets from which cuttings were removed (ACR and LCR) produced more tubers than the rooted cuttings (RAC and RLC); however, the most tubers were produced by WIP. RAC produced highest tuber yields followed by WIP and RLC. Intact WIP and plantlets with cuttings removed (ACR and LCR) produced twice as many tubers <40 g as those from rooted cuttings (RAC and RLC). The yield (kg/m²) as well as the number of tubers per m² increased with the increasing planting density within the densities tested.     

A selection procedure in wheat for stress environment

Summary A simple and effective selection procedure for identifying lines with wide adaptation and ability to do well under drought is outlined, supported with experimental data involving diverse and high yielding populations of bread wheat.The effect of selections for local adaptation to stress environment is found to be inferior as compared to selection for developmental traits in a favourable environment. Data on selection for developmental traits have shown favourable correlated associations with more precision in the estimate of components of genetic variation and heritability and larger magnitude of response to selection as compared to selection for yield components in stress environment.The developmental characters such as early vigour and synchronous tillering, days to heading and ear length which show stability over different environments are found to be important components of wide adaptation and productivity under moisture-stress.Presented at the Symposium on Planning for the Drought of the National Institute of Sciences, held in New Delhi, India, 4–6 May, 1969.     

Prevalence of ulcers of the squamous gastric mucosa in standardbred horses

This study was performed to determine the prevalence of ulcers in the gastric squamous mucosa in Standardbred racehorses. Observations were performed at monthly intervals between the beginning of their training season and their 1st qualifying race. This study also identified risk factors at different levels of race training. Forty-eight Standardbred racehorses from 3 training stables in Quebec, Canada, were studied. Baseline historical information and gastroscopic findings were recorded at the beginning of the trial, and once a month thereafter, between December 2001 and June 2002, until the horse's 1st qualifying race or the end of the training. Intensity of training ranged from jogging to intensive training just before the 1st race and was assigned an ordinal score. Location of squamous ulcers and their appearance were observed on gastroscopy, and an ordinal score was assigned. Prevalence of squamous ulcers from the 2nd through the 4th month (72-88%) of training remained at a significantly higher level (P = .002 to .04) than at the onset of the study (38%) and was also higher in intensely trained horses than in joggers (93% versus 56%). Moderate or more intensive training increased the odds (odds ratio [OR], 3.39; confidence interval [CI], 1.34-8.56; and OR, 11.4; CI, 3.21-40.5, respectively) of detecting ulcers with higher scores. These odds were also higher in trotters (OR, 2.17; CI, 1.07-4.43) than in pacers and generally increased with the duration of training. Duration of training, training level, and gait type also influenced the number of sites with ulcers in the same way. Ulcers had higher scores along the lesser curvature (LC) and the margo plicatus (MP) areas of the stomach. It was concluded that squamous ulcers appeared early in the training of Standardbred racehorses, that the number of sites affected and the ulcer score are related to the intensity of training, and that trotters are more prone to squamous ulcers than pacers.     

Potentiation of immune response of live lentogenic Newcastle disease vaccine using adjuvant

Tropical Animal Health and Production -     

Relationship Between Allelopathic Effects and Functional Traits of Different Allelopathic Potential Rice Accessions at Different Growth Stages

In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperatureleaf stagelight,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity.     

Molecular and genetic comparisons of two serotypes of epizootic hemorrhagic disease of deer virus

The virus-specific double-stranded genome RNA of 2 serotypes of epizootic hemorrhagic disease of deer virus (EHDV) was evaluated by use of coelectrophoresis in polyacrylamide and agarose gel systems. The molecular weights of virion RNA segments were 0.32 to 2.57 X 10(6) for EHDV-1 and 0.33 to 2.54 X 10(6) for EHDV-2. Seven of 10 double-stranded RNA segments of the 2 serotypes had different electrophoretic mobilities in the polyacrylamide-gel electrophoresis system. Although the individual RNA segments of each serotype contained unique RNA sequences determined on the basis of 2-dimensional polyacrylamide-gel electrophoresis analysis of oligonucleotides, the corresponding segments of the 2 serotypes were found to be comparable and at least 1 pair of RNA segment was almost identical. Virus-specific polypeptides for the 2 serotypes were compared by use of gel electrophoresis. Eleven polypeptides were detected for EHDV-1 and 10 for EHDV-2. Six corresponding polypeptides of these 2 serotypes had different electrophoretic mobilities, indicating that these corresponding polypeptides differ in their molecular weights. A genetic relationship was not determined between the 2 EHDV serogroups and the blue-tongue serogroup viruses, using oligonucleotides mapping.     

The use of non-prion biomarkers for the diagnosis of Transmissible Spongiform Encephalopathies in the live animal

Scrapie and bovine spongiform encephalopathy (BSE) are major global concerns and the emergence of variant Creutzfeldt-Jakob disease (vCJD) has caused turmoil for blood transfusion services and hospitals worldwide. Recent reports of iatrogenic CJD (iCJD) cases following blood transfusions from Transmissible Spongiform Encephalopathies (TSE)-infected donors have fuelled this concern. Major diagnostic tests for BSE and scrapie are conducted post-mortem from animals in late stages of the disease. Although the lymphoreticular system is involved in the earlier pathogenesis of some forms of sheep scrapie and vCJD, which presents great opportunity for diagnostic development, other TSE diseases (some strains of scrapie, sporadic CJD (sCJD) and bovine BSE) do not present such a diagnostic opportunity. Thus, there is an urgent need for pre-mortem tests that differentiate between healthy and diseased individuals at early stages of illness, in accessible samples such as blood and urine using less invasive procedures. This review reports on the current state of progress in the development and use of prion and non-prion biomarkers in the diagnosis of TSE diseases. Some of these efforts have concentrated on improving the sensitivity of PrPSc detection to allow in vivo diagnosis at low abundances of PrPSc whilst others have sought to identify non-prion protein biomarkers of TSE disease, many of which are still at early stages of development. In this review we comment upon the limitations of prion based tests and review current research on the development of tests for TSE that rely on non-prion disease markers in body fluids that may allow preclinical disease diagnosis.     

Leaf yield component combining abilities in mulberry (Morus spp.)

A line × tester analysis was carried out in mulberry (Morus spp.) to determine the genetic interaction in the expression of various quantitative characters including leaf yield. Eight clonal varieties were selected, 3 of them were designated as lines (♀) viz. Berhampore-1, China white and MS-5 and 5 of them were called as testers (♂) viz. Mandalaya, Kosen, Assamjati, MS-1 and Kajli. Combining ability studies were conducted on these parents along with their F₁ hybrids for the variables laminar index, growth rate, weight of 100 dry leaves, number of primary branches per plant, plant height, nodal distance, leaf-twig ratio, aerial biomass, moisture content, moisture retention capacity and leaf yield. Broad genetic variability was observed among the genotypes. The ratio of General Combining Ability (GCA) and Specific Combining Ability (SCA) indicated the predominance of non-additive genes in mulberry. While China white (female) and MS-1 (male) were the best general combiners among the parents, Berhampore-1 × Kajli was the best cross for leaf yield. Results suggest that selective crossing followed by proper screening may be the best approach for breeding of high yielding varieties in mulberry. This revised version was published online in July 2006 with corrections to the Cover Date.