The distribution of important sero-complexes of flaviviruses in Malaysia

Tropical Animal Health and Production - Flaviviruses (FVs) are arthropod-borne viruses of medical and veterinary importance. Numerous species of FVs have been isolated from various host; mainly...     

Appraisal of interpretation criteria for the single intra-dermal comparative cervical tuberculin test for the diagnosis of tuberculosis in dromedary camels in Ethiopia

Tropical Animal Health and Production - Dromedary camels are the main sources of milk, meat and income for the Ethiopian pastoralists as they withstand the harsh environments of the regions of the...     

Morphohistological examination on somatic embryogenesis of Musa acuminata cv. Mas (AA)

Somatic embryogenesis is a routine method in obtaining mass-production of plantlets especially in Musa spp. Somatic embryogenesis is a process characterized by a series of morphological changes leading to plant regeneration. Therefore it is important to identify stages in somatic embryogenesis through morphological and histological characteristics. In this study, stages of somatic embryogenesis through morphohistological study could differentiate between embryogenic callus consisting of somatic embryos and non-embryogenic callus. In Musa spp., globular to torpedo shaped somatic embryos resulted in good suspension cultures followed by recovery of somatic embryos during developmental stage. The morphological observations were supported by histological sections of structures at all particular stages. Histological examination also revealed the vascular connection in germinated somatic embryos which later turned into a complete plantlet.     

Effective use of the TSPY gene‐specific copy number in determining fetal DNA in the maternal blood of cynomolgus monkeys

Since the available concentration of single‐copy fetal genes in maternal blood DNA is sometimes lower than detection limits by PCR methods, the development of specific and quantitative PCR detection methods for fetal DNA in maternal blood is anticipated, which may broaden the methods that can be used to monitor pregnancy. We used the TaqMan qPCR amplification for DYS14 multi‐copy sequence and the SRY gene in maternal blood plasma (cell‐free DNA) and fractional precipitated blood cells (cellular DNA) from individual cynomolgus monkeys at 22 weeks of pregnancy. The availability of cell‐free fetal DNA was higher in maternal blood plasma than that of cellular DNA from fractional precipitated blood cells. There was a significantly higher (P < 0.001) mean copy number of fetal male DYS14 from maternal plasma (4.4 × 10⁴ copies/mL) than that of detected fetal cellular DNA from fractional blood cell pellets. The sensitivity of the DYS14 PCR assay was found to be higher than that of the SRY assay for the detection of fetal DNA when its presence was at a minimum. The DYS14 assay is an improved method for quantifying male fetal DNA in circulating maternal blood in the primate model.     

<Emphasis Type="Italic">Rhizobium</Emphasis>,<Emphasis Type="Italic"> Bradyrhizobium</Emphasis> and<Emphasis Type="Italic"> Agrobacterium</Emphasis> strains isolated from cultivated legumes

The present study was conducted to isolate and characterize rhizobial strains from root nodules of cultivated legumes, i.e. chickpea, mungbean, pea and siratro. Preliminary characterization of these isolates was done on the basis of plant infectivity test, acetylene reduction assay, C-source utilization, phosphate solubilization, phytohormones and polysaccharide production. The plant infectivity test and acetylene reduction assay showed effective root nodule formation by all the isolates on their respective hosts, except for chickpea isolate Ca-18 that failed to infect its original host. All strains showed homology to a typical Rhizobium strain on the basis of growth pattern, C-source utilization and polysaccharide production. The strain Ca-18 was characterized by its phosphate solubilization and indole acetic acid (IAA) production. The genetic relationship of the six rhizobial strains was carried out by random amplified polymorphic DNA (RAPD) including a reference strain of Bradyrhizobium japonicum TAL-102. Analysis conducted with 60 primers discriminated between the strains of Rhizobium and Bradyrhizobium in two different clusters. One of the primers, OPB-5, yielded a unique RAPD pattern for the six strains and well discriminated the non-nodulating chickpea isolate Ca-18 from all the other nodulating rhizobial strains. Isolate Ca-18 showed the least homology of 15% and 18% with Rhizobium and Bradyrhizobium, respectively, and was probably not a (Brady)rhizobium strain. Partial 16S rRNA gene sequence analysis for MN-S, TAL-102 and Ca-18 strains showed 97% homology between MN-S and TAL-102 strains, supporting the view that they were strains of B. japonicum species. The non-infective isolate Ca-18 was 67% different from the other two strains and probably was an Agrobacterium strain.     

Identification of a putative cellulase gene in the giant freshwater prawn,Macrobrachium rosenbergii (De Man, 1879)

Nutrition plays an important role in the development of all organisms and in particular that of farmed aquatic species where costs associated with feed can often exceed 60% of total production costs. Crustacean species in addition, have the added metabolic requirement for regular moulting to allow normal growth and this requires large amounts of energy in the form of sugars (glucose). The current study explored the capacity of the giant freshwater prawn to produce endogenous cellulose‐degrading enzymes capable of extracting nutrients (simple sugars) from plant sources in formulated feeds used in the prawn aquaculture industry. We identified a putative cellulase cDNA fragment in the target organism of 1576 base pairs in length of non‐microbial origin that after protein modelling exhibited a TM‐score of 0.916 with a described cellulase reported from another crustacean species. The functional role of cellulase enzymes is to hydrolyse cellulose to glucose and the fragment identified in GFP was highly expressed in the hepatopancreas, the site of primary food digestion and absorption in crustaceans. Hepatopancreatic tissue from Macrobrachium rosenbergii also showed active digestion of cellulose to glucose following an endoglucanase assay. Cellulase gene(s) are present in the genomes of many invertebrate taxa and play an active role in the conversion of cellulose to available energy. Identification and characterization of endogenous cellulase gene(s) in giant freshwater prawn can assist development of the culture industry because the findings confirm that potentially greater levels of low‐cost plant‐material could be included in artificial formulated diets in the future without necessarily compromising individual growth performance. Ultimately, this development may contribute to more efficient, cost‐effective production systems for freshwater prawn culture stocks that meet the animal's basic nutritional requirements and that also support good individual growth rates.     

Effect of the UV-C Radiation on Shelf Life of Vacuum-Packed Refrigerated Pirarucu (Arapaima gigas) Fillets

The effect of Ultraviolet radiation type C (UV-C) radiation (0.100 ± 0.010 J/cm²) on shelf life of Arapaima gigas fillets stored at 4 ± 1°C for 18 days was investigated. The samples were analyzed for total aerobic mesophilic bacteria (TAMB) counts; total aerobic psychrotrophic bacteria (TAPB) counts; Enterobacteriaceae; purge loss; pH; lipid oxidation; total volatile bases (TVB-N); ammonia; biogenic amines (BAs); and L*, a*, and b* values. UV-C radiation increased (P < 0.05) the generation time of all bacterial groups evaluated, increasing the shelf life by 2 days. UV-C-treated fillets showed lower (P < 0.05) L* values, purge loss, pH, TVB-N, ammonia, and BAs levels than their control counterparts throughout the storage period. Moreover, UV-C treatment did not result (P > 0.05) in detrimental effects on lipid oxidation or a* and b* values. UV-C at 0.100 J/cm² demonstrated a good potential for use in A. gigas fillets and, therefore, it could be applied at industrial scale.     

Effects of dietary chromium chloride,nicotinic acid and copper sulphate on meat of broilers

1.?Combinations of chromium and copper were added to the diet to assess their effects on broiler meat characteristics.

2.?For this purpose 175 one-day-old broiler chicks were divided into 7 equal groups and were given treatment feeds containing copper sulphate, chromium chloride and nicotinic acid in different combinations.

3.?The study was carried out for 5 weeks and samples were collected at the end of 15, 29 and 35 d of treatment and at 42 d after a withdrawal period of one week.

4.?Cholesterol content had decreased significantly in breast meat at d 29 in all treatment groups. In thigh meat, it decreased significantly at d 29 in groups receiving two concentrations of chromium + two concentrations of copper. Cholesterol content remained lower even after withholding the treatment for one week.

5.?Crude fat content decreased significantly in breast meat in all treatment groups. In thigh meat, at d 29, a significant reduction in crude fat was observed only in birds receiving low chromium and high copper.

6.?Crude protein at d 29 increased significantly in breast meat of birds receiving low chromium and high copper, and low or high chromium, while it decreased significantly in treatment groups after withholding the treatment. In thigh meat, at d 29, it increased significantly in treatment groups but decreased significantly after withholding the treatment.

7.?It was concluded that chromium and copper, along with nicotinic acid, have modulating effects on broiler meat under tropical conditions.     

Exploring student attitudes to directed self-learning online through evaluation of an Internet-based biomolecular sciences resource

RATIONALE FOR THE STUDY: In 2000, funding was awarded by the University of Glasgow's Learning and Teaching Development Fund (L&TDF) for the authors to develop an interactive, online learning resource for veterinary biomolecular sciences teaching. This course is a core component of the veterinary undergraduate curriculum at the university. Evaluations were carried out to gauge students' experiences of using the resource as a basis for exploring students' attitudes toward online, independent learning. METHODOLOGY: Peers were asked to review the design and content of four modules, also evaluated by students using questionnaires and focus group discussions. Additionally, students were observed using the modules. Both first-year students and second-year direct-entry students (i.e., students entering the veterinary program with advanced training) participated in the evaluation, which allowed for some comparison between the groups. One cohort used the modules independently, and their responses were compared with the cohorts that used the modules in scheduled classes. RESULTS AND CONCLUSIONS: The evaluations indicate that this is a useful resource that could act as a template for other courses within the veterinary undergraduate curriculum, particularly for learning of basic sciences. On average, first-year and timetabled students rated the program more highly overall, rated the program more highly in relation to previous instruction, and rated tutor presence as more important than second-year direct-entry and independent students did. The lower rating given to tutor presence by second-year direct-entry and independent students indicates that they are more confident using the modules without tutor supervision.