Application of the indirect fluorescent antibody test for diagnosis ofTheileria hirci infection of sheep: Using cell culture schizont antigen

Summary The indirect fluorescent antibody test was applied for detection of circulating antibodies in sheep as a result ofTheileria hirci infections. A schizont antigen was prepared from anin vitro culture suspension of lymphoid cells infected withT. hirci macroschizonts. The peak antibody titre of1/8,192 was reached24 days after the initial antibody rise in the sheep experimentally infected by means ofHyalomma anatolicum anatolicum ticks.

---

Resumen Se utilizó la prueba indirecta de anticuerpos fluorescentes para la detección de anticuerpos circulantes en ovejas infectadas conTheileria hirci. Se preparó un antígeno de esquizontes del cultivoin vitro de una suspensión de células linfoides infectadas con macroesquizontes deT. hirci. El nivel más alto de anticuerpos 1/8192, se obtuvo 24 días después de la respuesta inmunitaria inicial en la oveja infectada experimentalmente utilizando como vectores garrapatasHyalomma anatolicum anatocilum.

---

Résumé Le test de la recherche des anticorps par immunofluorescence indirecte a été appliqué à la détection des anticorps circulants de mouton des aux infections parTh. hirci. Un antigène a été préparé à partir d'une suspensionin vitro de cellules lympho?des infectées par des macroschizontes deTh. hirci. Le taux le plus élevé en anticorps (1/8192) a été atteint 24 jours après la première sortie d'anticorps chez le mouton infecté expérimentalement par des tiques du genreHyalomma anatolicum anatolicum.

     

On Red Rot of Sugarcane

Abstract

Red rot is a very serious disease of sugarcane. It was first described by Went in 1893 (56). Since then it has been found to cause epiphytotics in different countries. The surest symptom of the disease is the reddening of the internal internodal tissues with crossbars of white patches in the reddened area. This red colour is caused by a dye which is secreted by the host and is antagonistic to the red rot fungus. Infection takes place through mother setts, holes in the nodal regions, the cut ends of the seed canes and other injuries. The disease causes damage to the sugarcane drop mainly by reducing the crop stands and by reducing the sucrose content of the cane juice. Methods of chemical control are mentioned, although the importance of good husbandry is stressed. Use of resistant varieties of sugarcane is recommended.     

Influence of Nitric Oxide Application on Some Biochemical Aspects,Endogenous Hormones,Minerals and Phenolic Compounds of Vicia faba Plant Grown under Arsenic Stress

Arsenic is a non-essential and toxic heavy metal, which can cause physiological disorder in plants. The present study was undertaken to examine the possible roles of sodium nitroprusside (SNP, a donor of NO) in protection against oxidative damage due to arsenic (As) toxicity in faba bean (Vicia faba L.) plants. In this study, we measured physiochemical parameters (photosynthetic pigments, lipid peroxidation, endogenous hormones, minerals and phenolic contents) in faba bean plants exposed to AS (100, 200 and 400 µM) alone or combined with NO (100 µM). The results showed that application of all concentrations of arsenic (100, 200 and 400 µM) induced decrease on growth parameters, seed yield, photosynthetic pigments, phytohormones, minerals contents (N^3?, P^3?, K⁺, Ca²⁺?and Mg²⁺) as compared to control plants but increased lipid peroxidation, Na?⁺ and total phenolic compounds fraction. Foliar application of 100 µM NO reversed the inhibition induced by As treatment. In addition, arsenic was undetected in harvested seeds at all applied concentrations of arsenic. Therefore, it could be concluded that NO might account for the alleviating effect of As stress on Vicia faba plants.     

Functional amino acids stimulate muscle development and improve fillet texture of Atlantic salmon

Sufficient firmness is essential for consumer appreciation and the suitability for processing of fish fillets. The objective of this study was to investigate the effect of functional amino acids (AA) on fillet texture and muscle development of Atlantic salmon. Triplicate net pens of 105 g salmon were fed a standard diet, or the same diet with added 15 g/kg arginine or 15 g/kg glutamate during a 5‐month rearing period. The growth rate and FCR (0.91–0.92) showed no significant dietary effects (body weight 864–887 g). Glutamate supplementation resulted in delayed postmortem glycogen degradation (pH drop) and rigour development, along with improved fillet firmness and intercellular myofibre integrity. An in vitro study with salmon myosatellite cells showed that exogenous glutamine or arginine increased the expression of muscle growth markers (myog, tnnl2, myl) at both 8 and 16°C culture temperature. The expression of a marker for proteolysis (ctsb), myl and myog were highest for the glutamine treatment at 16°C. Significant interaction between exogenous AA and temperature indicated elevated AA requirement when growth is accelerated. It is concluded that AA from the glutamate family are vital for fillet firmness. The dispensable glutamine and glutamate appear more critical compared to arginine, particularly during high‐performance periods.     

Morphological and Genetical Variability among Rhizoctonia solani Isolates Causing Sheath Blight Disease of Rice

Eighteen isolates of Rhizoctonia solani collected from infected rice plants in four different locations of Bangladesh were studied by using morphological characters and molecular markers. Anastomosis study with a reference isolate confirmed that all the isolates belonged to R. solani. Significant variation was observed in sclerotial size, shape and distribution. Un-weighted pair group method with arithmetic mean dendrogram constructed based on the Gower's general similarity coefficient showed that these isolates were grouped into four clusters at the 0.68 similarity coefficent according to morphological characters. Cluster I was a major cluster consisting of 13 isolates, while clusters Ⅱ to Ⅳ consisted of 1 or 2 isolates. Analyses by variable number of tandem repeat and amplified fragment length polymorphism markers showed that the isolates were grouped into five and three clusters at a similarity coefficient of 0.64 and 0.69, respectively. Although most of the variability was found between isolates from different regions as expected, significant variation was observed within the isolates collected from similar agro-ecological regions. Our results suggest the presence of different races of R. solani within the same local geographic regions.     

Effects of Prohexadione Calcium on growth and gibberellins contents of Chrysanthemum morifolium R. cv Monalisa White

The effect of Prohexadione Calcium (Pro-Ca) and daminozide was observed on the growth characteristics and endogenous gibberellin contents of Chrysanthemum morifolium R. cv Monalisa White. Three concentrations viz. 100, 200 and 400 ppm of Pro-Ca and a single concentration of daminozide (800 ppm) were applied three times with 7 days interval on three weeks old plant under greenhouse condition. Pro-Ca suppressed the plant length up to 30.7% while daminozide inhibited up to 27.12% at optimum concentration. The chlorophyll contents and stem diameter were higher than control, while the fresh weight and flower number insignificantly reduced with such treatments. Gibberellin (GA) analysis showed that Pro-Ca and daminozide application significantly lowered bioactive GA₁ content, although the amount of its immediate precursor GA₂₀ was fractionally higher. Bioactive GA₄ content was slightly higher than the control while significant difference in GA₉ was found between the plants treated with Pro-Ca and daminozide. Current study showed that both early C13 hydroxylation and non-C13 hydroxylation pathways of GA biosynthesis are operational in C. morifolium.     

Identification of bacterial agents causing mortality in postlarvae of giant freshwater prawn (Macrobrachium rosenbergii) in south‐west coastal districts of Bangladesh

Following an incidence of freshwater prawn Macrobrachium rosenbergii postlarvae (PL) mortality in hatcheries in summer 2012, samples from dead PL, rearing water and prawn feed from two south‐west coastal districts of Bangladesh were collected to isolate, identify and characterize the agents causing PL mortality. Antibiogram profile of sixteen randomly selected bacteria, isolated from dead PL, that grew on TCBS, to 20 different antibiotics belonging to 12 major groups revealed that the drug resistance pattern varied from moderate (56% to the drugs: ciprofloxacin, cefotaxime, nitrofurantoin, kanamycin) to complete (to penicillin, ceftazidime and oxacillin) level. To identify the isolates, amplified rDNA restriction analysis (ARDRA) classified them in to four groups, and RAPD (randomly amplified polymorphic DNA) typing yielded nine different types of isolates within these four ARDRA groups. The 16S rDNA gene sequences identified that the groups were genotypically diverse belonging to the bacterial species: Enterobacter cloacae, Klebsiella pneumoniae, Exiguobacterium profundum and Enterococcus casseliflavus, respectively, that all demonstrated their killing potential to PLs in a simulated environment. The study therefore identified four different bacterial pathogens, one of which, Exiguobacterium profundum is reported for the first here in Bangladesh, that demand special consideration for disease management strategy.     

Integrated Duck-cum-Fish Farming in Bangladesh

An experiment on integrated duck-cum-fish farming was conducted in 11 ponds of 0.1 ha each at the Fisheries Research Institute, Mymensingh, Bangladesh. Khaki Campbell layer ducks Anas platyrhychos were housed directly over the pond water surface at 200, 400 and 500 dncks/ha. Each density had three replicate ponds and two ponds had no ducks. Fish fingerlings were stocked at a total density of 8,850/ha. The species composition was silver carp Hypophthalmicthys molitrix 33.9%; catla Catla catla 12.4%; rohu Labeo rohita 18.1%; mrigal Cirrhina mrigala 28.8%. grass carp Ctenopharyngodon idella 1.4% and sor puti Puntius gonlonotus 5.4%. The fish were not given any supplemental feed, and the ponds were not fertilized except for the split duck feed and duck manure falling directly into the ponds. Ducks were fed with a feed formulated from locally available ingredients.
After one year the fish were harvested. The yield of fish increased with an increase in duck density. Highest net fish production of 4,250 kg/ha/yr was obtained from ponds with 500 ducks/ ha, compared to 490 kg/ha/yr from the control ponds. Manure of each duck contributed a net fish yield of 6.9–7.5/yr. Average egg production was 237 eggs per female duck per year. Economic analysis of the technology showed a net profit of about 100% of the total costs, indicating the economic viability of the technology.     

Natural infection rates of Hyalomma anatolicum anatolicum with theileria in Sudan

Hyalomma anatolicum anatolicum ticks were collected around cattle pens at two locations close to Khartoum. They were assessed for theileria infection by four methods. Salivary glands were stained whole with methyl green pyronin and examined for parasite masses. Adult ticks were partially fed on rabbits, ground up in medium, and the suspensions were examined in Giemsa stained smears and by inoculation into bovine lymphocyte cultures. Ticks were fully fed on calves which were monitored for developing theileriosis. H a anatolicum were found infected with parasite masses similar to those seen in experimental infections with T annulata. At one site 38 per cent of 102 ticks were infected and the mean number of parasite masses per tick for the whole sample was 37. At the other site 86 per cent of 156 ticks were similarly infected and the mean parasite masses per tick was 19.5. Suspensions of sporozoites contained sporozoites typical of those found in experimental preparations of T annulata. Sporozoites harvested from ticks from both locations infected and transformed normal bovine lymphocyte cultures. H a anatolicum ticks from both locations produced fatal theileria infection in susceptible calves.