Characterization of dhaincha accessions based on morphological descriptors and biomass production
Forty five accessions of dhaincha germplasms were collected from different parts of Bangladesh and characterized on the basis of morphological descriptors and biomass production ability. Thirty eight accessions were identified as Sesbania bispinosa, four as S. cannabina and two as unidentified Sesbania spp. One accession as S. rostrata was included for comparison. Both at seedling and maturity stages, wide and significant differences were observed among the accessions of different dhaincha germplasms for their biomass production capability and other morphological descriptors. At the seedling stage, total dry mass (TDM) production varied from 10.2 to 41.6g 30-plants–1. At the maturity stage, plant height, total number of branches and base diameter of dhaincha germplasms varied from 347.5–474.7cm, 10.4–23.7, and 1.9–4.9cm, respectively. The highest amount (4.10kg 10-plants–1) of above-ground TDM was produced in one accession of unidentified Sesbania sp. followed by S. rostrata and one accession of S. cannabina (3.85kg 10-plants–1), and the lowest TDM (0.9kg 10-plants–1) was measured in two accessions of S. bispinosa. It may be concluded that the biomass production capability of at least two accessions of local Sesbania germplasms were higher/comparable to that of exotic S. rostrata. It will be too early to make a conclusive remark based on only a few dhaincha germplasms. A detailed study with a large number of germplasms collected from whole Bangladesh is obviously needed to reach in a precise conclusion.
Nutritive value and antinutritional factors in different varieties of Sesbania seeds and their morphological fractions
Abstract Four different Sesbania seeds, S. aculeata, S. rostrata, S. sesban (accession 10865D) and S. sesban (accession 15019D), were analysed for their physicochemical properties, nutritive values and antinutritional factors (ANFs) in order to assess feasibility of use as an unconventional food resource. Seeds of both the accessions of S. sesban were smaller in size but their seed coat+endosperm fractions were higher (56–57%) than those of S. aculeata and S. rostrata (49–51%). S. rostrata had a lower hydration capacity, hydration index, swelling capacity and swelling index than other seeds. The crude protein content in different seeds ranged from 29.1 to 33.1%, crude lipid 4.7–6.0%, crude fibre 10.9–15.8%, total crude carbohydrates 44.6–47.4% and gross energy 19.2–20.0 kJ/g. Except for isoleucine, histidine and tryptophan, all other essential amino acids were deficient compared to the FAO/WHO reference pattern. The seed fractions showed similar amino acid pattern to that of whole seed with slightly higher values. Palmitic, stearic, oleic, linoleic and linolenic acids were the major fatty acids (FAs) and the total unsaturated and essential FAs ranged from 78.1 to 82.3% and 77.2 to 80.3%, respectively, with S. aculeata having the highest value. The ranges of starch fractions in different seeds were: total starch 17.5–20.4%, digestible starch 7.3–10.2% and resistant starch 10.2–11.2%. The soluble sugar contents ranged from 8.8 to 10.6%. The ranges of antinutritional factors in different seeds were: total phenols 2.96–5.95%, tannins 1.97–2.25%, condensed tannins 1.82–5.14%, phytic acid 1.89–2.37%, saponins 0.52–1.46%, trypsin inhibitors 5.25–14.0 (mg trypsin inhibited per gram of sample) and lectin activity 10.2–20.5 units. There was a wide variation in the ANFs contents of seed coat+endosperm, and cotyledons.
Genotypic diversity in field isolates of Babesia bovis from cattle with babesiosis after vaccination.
OBJECTIVE
To determine whether particular genotypes of Babesia bovis were common to field isolates obtained from cattle properties in Queensland where the B bovis vaccine had apparently failed.


DESIGN
A comparative study of polymerase chain reaction genotypes in different populations of B bovis.


PROCEDURE
Two polymerase chain reaction assays were applied to analyse DNA extracts of B bovis vaccine (K, T and Dixie strains) and 27 field isolates from 24 properties where disease outbreaks had occurred despite the use of the vaccine. To evaluate the stability of the genotypes identified, 11 of the field isolates were inoculated into experimental cattle that had either been previously vaccinated with T strain or not vaccinated.


RESULTS
No particular genotype of B bovis was responsible for the problems observed in previously vaccinated herds. None of the isolates had genotypes identical to the vaccine strains used. No geographic trends among the genotypes were observed. Isolates that originated from the same property also had different genotypes. Blood passage of the 11 field isolates in either previously vaccinated or nonvaccinated cattle did not alter the original genotype.


CONCLUSION
No particular genotypes identified by the Bv80 and BvVA1 polymerase chain reaction assays could be associated with vaccine failures.