Dietary lysine requirement of fingerling Catla catla (Hamilton) based on growth, protein deposition, lysine retention efficiency, RNA/DNA ratio and carcass composition

A 12-week experiment was conducted to quantify dietary lysine requirement of fingerling Catla catla (3.65 ± 0.05 cm; 0.58 ± 0.02 g) by feeding casein–gelatine-based diets (33.0 % crude protein; 14.3 kJ/g digestible energy) with six levels of l-lysine (1.25, 1.50, 1.75, 2.00, 2.25 and 2.50 % dry diet). The experiment was conducted in eighteen 70-L indoor polyvinyl circular troughs provided with a water flow-through system (1–1.5 L/min). Live weight gain (LWG), feed conversion ratio (FCR), protein deposition (PD), lysine retention efficiency (LRE%) and RNA/DNA ratio were used as the response criteria. Second-degree polynomial regression analysis at 95 % maximum and minimum response of LWG and FCR data exhibited the lysine requirement between 1.8 and 1.9 % dry diet, corresponding to 5.5–5.7 % dietary protein. Regression analysis of PD, LRE and RNA/DNA ratio yielded the requirement between 1.7 and 1.8 % dry diet, corresponding to 5.2–5.5 % dietary protein. Since live weight gain and protein deposition are the key parameters for estimating nutrient requirement, these tools were used to recommend the lysine requirement of fingerling C. catla which ranges between 1.7 and 1.8 % dry diet. Data generated during this study will be useful to formulate lysine-balanced feed for intensive culture of this fish.     

Rising CO2 can alter fodder–weed interactions and suppression of Parthenium hysterophorus

Three C₄ grass (Setaria incrassata, Astrebla squarrosa and Bothriochloa decipiens) and one C₃ legume (Clitoria ternatea) suppressive fodder species, were re‐evaluated against the growth of the C₃ Parthenium hysterophorus under an ambient (390 μmol mol^?1) and an elevated atmospheric CO₂ concentration (550 μmol mol^?1). Under the elevated atmospheric CO₂, shoot dry biomass and suppression index (SI) value of the C₄ S. incrassata were both reduced by 32% and 0.7 respectively, while those for A. squarrosa were reduced by 23% and 0.3. In contrast and under the same elevated atmospheric CO₂ concentration, the shoot dry biomass and SI of the C₄ B. decipiens were increased by 8% and 0.1 respectively, while those for the C₃ C. ternatea were increased by 38% and 0.8. Our results suggest that C₃ fodder plants along with certain C₄ species could be utilised for the effective management of P. hysterophorus under the future elevated atmospheric CO₂ conditions. However, this system needs more fodder species to be investigated. Our results suggest that rising CO₂ per se may alter the efficacy of suppressive fodder management of an invasive C₃ species, P. hysterophorus.     

New α-Glucosidase Inhibitory Triterpenic Acid from Marine Macro Green Alga Codium dwarkense Boergs

The marine ecosystem has been a key resource for secondary metabolites with promising biological roles. In the current study, bioassay-guided phytochemical investigations were carried out to assess the presence of enzyme inhibitory chemical constituents from the methanolic extract of marine green alga—Codium dwarkense. The bioactive fractions were further subjected to chromatographic separations, which resulted in the isolation of a new triterpenic acid; dwarkenoic acid (1) and the known sterols; androst-5-en-3β-ol (2), stigmasta-5,25-dien-3β,7α-diol (3), ergosta-5,25-dien-3β-ol (4), 7-hydroxystigmasta-4,25-dien-3-one-7-O-β-d-fucopyranoside (5), 7-hydroxystigmasta-4,25-dien-3-one (6), and stigmasta-5,25-dien-3β-ol (7). The structure elucidation of the new compound was carried out by combined mass spectrometry and 1D (¹H and ¹³C) and 2D (HSQC, HMBC, COSY, and NOESY) NMR spectroscopic data. The sub-fractions and pure constituents were assayed for enzymatic inhibition of alpha-glucosidase. Compound 1 showed significant inhibition at all concentrations. Compounds 2, 3, 5, and 7 exhibited a dose-dependent response, whereas compounds 4–6 showed moderate inhibition. Utilizing such marine-derived biological resources could lead to drug discoveries related to anti-diabetics.     

Antimicrobial Susceptibility of 41 Burkholderia mallei Isolates From Spontaneous Outbreaks of Equine Glanders in Punjab,Pakistan

Minimum inhibitory concentrations (MICs) of 20 antimicrobial agents for 41 isolates of Burkholderia mallei from natural outbreaks of equine glanders were determined by agar dilution. All isolates were intrinsically resistant to ampicillin (MIC₉₀ ≥128). Resistance to other antimicrobials was as follows: 95.1% to amoxicillin and cephradine, 85.4% to cefuroxime and norfloxacin, 68.3% to ceftizoxime and ceftriaxone, 61.1% to ceftiofur, 58.5% to oxytetracycline, 41.5% to ciprofloxacin, 58.5% to roxithromycin, 17.1% cefotaxime, and 12.2% clarithromycin. Overall resistance patterns revealed that 17% of isolates were simultaneously resistant to amoxicillin, cephradine, cefuroxime, ceftizoxime, ceftriaxone and norfloxacin. None of the isolates were resistant to amoxicillin-clavulanic acid, doxycycline, chloramphenicol, gentamicin or trimethoprim-sulphadiazine. Mode MICs for these antimicrobials were 2, 1, 8, 4 and 1 μg/ml, respectively. A majority of the isolates (∼ 94%) were susceptible to both enrofloxacin and ofloxacin. These data provide an updated perspective on susceptibility profiles of current strains of B. mallei in an endemic area.     

Detection of <Emphasis Type="Italic">Mycobacterium avium</Emphasis> subsp. <Emphasis Type="Italic">paratuberculosis</Emphasis> in tissue samples of cattle and buffaloes

Tissue samples were collected at random from cattle (Bos taurus) and buffalo (Bubalus bubalis) from an abattoir of the district of Lahore and were analyzed for the presence of Mycobacterium avium subsp. paratuberculosis and Mycobacterium bovis through acid-fast staining and polymerase chain reaction (PCR). Body condition of animals and diarrhea were recorded. Most of the animals were emaciated. Diarrhea was noticed in 15.6% of buffaloes and 19.2% of cattle. Intestinal pathology was observed in 29% of buffaloes and 32.8% of cattle. Number of mesenteric lymph node (MLN) showing gross lesions was a bit higher (35.6%) in cattle than buffalo (31.2%). Acid-fast staining of tissue scraping smears revealed the presence of acid-fast bacilli (AFB) in 17.4% intestinal and 16.4% MLN tissue samples in buffalo, while in cattle 19.2% intestinal and 17.8% MLN were found positive for AFB. In buffaloes, PCR confirmed 12.8% intestinal and 12.4% MLN positive samples for M. avium subsp. paratuberculosis. However, in cattle, PCR analysis demonstrated 14.2% positive results for M. avium subsp. paratuberculosis in both MLN and intestinal tissue samples. PCR also confirmed M. bovis in 5.8% of cattle and 5% of buffalo MLN and intestinal tissues. PCR positive tissue samples for M. avium subsp. paratuberculosis were from those animals which were emaciated, having diarrhea, and severe gross lesions. AFB were also detected in tissue scraping smears of these animals. It is concluded that infection by various mycobacterium species can be differentiated by PCR, which is not possible by acid-fast staining technique.     

SCAR markers: A potential tool for authentication of herbal drugs

Randomly Amplified Polymorphic DNA (RAPD) is easy to develop and simple molecular marker, but lack of reproducibility makes it less reliable for authentication of herbal drugs. Besides RAPD, other popular PCR and non-PCR based markers like AFLP, ISSR, SSR and RFLP are also used for authentication. However, these also have disadvantages like use of radioactive isotopes, high cost and absolute requirement of sequence information. Therefore, it is a better option to improve the reproducibility of RAPD by converting RAPD amplicons into Sequence Characterized Amplified Region (SCAR) markers. SCAR markers are easy, reliable and reproducible thus, have an advantage over RAPD markers for authentication of medicinal herbs used in the preparation of traditional medicines. These markers however, have been developed for only a few medicinal herbs. This review is an attempt to evaluate critically the role of SCAR markers in authentication of medicinal herbs used in traditional formulations.     

A new triterpene glycoside from Centella erecta

A new (2α,3β)-23-sulphonyl-2,3-dihydroxyurs-12-en-28-oic acid O-α-l-rhamnopyranosyl-(1→4)-O-β-d-glucopyranosyl-(1→6)-O-β-d-glucopyranosyl ester (1) together with eighteen known compounds were isolated from Centella erecta (L.f.) Fern. Their structures were elucidated mainly by NMR and HRESIMS, as well as on comparison with the reported data.     

Changes in Mithun (Bos frontalis) spermatozoa during epididymal passage

Genital organs of 10 healthy, adult Mithun bulls (6-8 years old) that were slaughtered at the dwellings of tribal people for meat were collected. Immediately after collection, spermatozoa from 3 different regions of the epididymis, i.e. the head, body and tail, were obtained to study morphological changes of the spermatozoa during passage through these regions. The prevalence of proximal cytoplasmic droplets significantly decreased from the head to the tail of the epididymis. Conversely, the percentage of distal cytoplasmic droplets increased significantly from the head to the tail region. The incidence of tailless heads rose significantly from head to body and then reduced significantly in the tail region. The percentage of total head abnormalities did, however, not change markedly, but total mid-piece and tail abnormalities differed significantly between the three epididymal regions.     

Preparation and characterization of jute fabrics reinforced urethane based thermoset composites: Effect of UV radiation

Jute fabrics reinforced thermoset composites were prepared with different formulations using urethane acrylate oligomer, methanol, and benzyl peroxide. Jute fabrics were soaked in the prepared formulations and fiber content in the composites was optimized with the extent of mechanical properties. Among all the resulting composites, 55 wt% jute content at oligomer:methanol:benzyl peroxide=75:24.5:0.5 (w/w/w) ratio showed best mechanical properties. The optimized jute fabrics were cured under UV radiation at different intensities and their mechanical properties were measured. Jute fabrics were treated with potassium permanganate (KMnO₄) solution of different concentrations (0.01, 0.02, 0.03, and 0.05 wt%) for different soaking times (1–5 min) before the composite fabrication. Optimized jute fabrics (jute fabrics treated with 0.02 wt% KMnO₄ for 2 min soaking time) were soaked in the optimized formulation and cured under UV radiation at different intensities and measured their mechanical properties. Scanning electron microscopic investigation showed that surface modification improves fiber/matrix adhesion. Water uptake and soil degradation test of the treated and untreated composite samples were also performed.