Cladistics of Rhipicephalus microplus and laboratory assessment of acaricidal efficacy of different Cassia fistula extracts against R. microplus larvae.

The present study aimed to analyze the cladistics and population structure analysis of Rhipicephalus microplus ticks infesting buffaloes in Haryana, India, as well as the assessment of the anti-tick efficacy of the ethanolic extracts of Cassia fistula (bark, pod pulp, and flowers) against R. microplus larvae. The molecular characterization and population structure analysis were performed by targeting the amplification of the partial mitochondrial cytochrome C oxidase subunit 1 (cox1) gene, whereas anti-tick efficacy was evaluated using a larval packet test. The sequences generated herein revealed a homology of 98.26-100% to the GenBank-archived R. microplus sequences. In population structure analysis, high haplotype (0.500 ± 0.265) and low nucleotide (0.002 ± 0.001) diversities were recorded for the sequences generated in this study. Significantly negative neutrality indices were recorded for the overall dataset. The extracts were found to significantly affect mortality rates in a dose-dependent manner, and the ethanolic extracts of the bark, pod pulp, and flowers of C. fistula exhibited median lethal concentration (LC50) values of 27.989, 40.457, and 49.43 mg/mL, respectively. The LC50 value recorded for the combination of the ethanolic extracts of the bark, flower, and pod pulp of C. fistula was 19.724 mg/mL, whereas the synthetic acaricide ivermectin had an LC50 value of 351.56 mg/mL. In conclusion, R. microplus populations infesting cattle and buffalo hosts in India exhibited negligible genetic differentiation and high gene flow between them. Additionally, the combination of all C. fistula extracts could serve as a potential substitute for the synthetic acaricide.

Molecular characterization of Hyalomma dromedarii and evaluation of acaricidal potential of herbal methanolic extracts against H. dromedarii larvae in comparison to synthetic acaricides.

The present study had two aims: molecular characterization of Hyalomma dromedarii infesting one-humped camels of Haryana (North India), and assessment of the acaricidal potential of herbal methanolic extracts against H. dromedarii larvae in comparison to synthetic acaricides. Phylogenetics and population neutrality indices were assessed by targeting partial amplification of mitochondrial 16S rDNA sequences. Larval packet test (LPT) was performed to evaluate the acaricidal efficacy of herbal extracts (Ferula asafoetida and Trachyspermum ammi) and synthetic acaricides (deltamethrin and fipronil). Phylogenetic studies established the collected ticks to be H. dromedarii, exhibiting a homology of 99.8-100%. However, the present study isolates formed a different sub-clade compared to H. dromedarii sequences from Egypt, Senegal, Tunisia and Saudi Arabia. Nucleotide and haplotype diversity values were indicative of demographic expansion and low gene flow. Negative values of Tajima's D (-0.612) and Fu and Li's Fst (-0.479) highlighted deviations from neutrality and emphasized recent population expansion. The median lethal concentration (LC50) values recorded for T. ammi, F. asafoetida and their combination were 3.68, 2.87 and 2.59 mg/mL, respectively, whereas the 90% lethal concentration (LC90) values were 4.09, 3.58 and 3.35 mg/mL, respectively. It was also observed that the H. dromedarii population under study was completely susceptible to both the formulated synthetic acaricides. In conclusion, combination of methanolic extracts of F. asafoetida and T. ammi could provide a potential substitute to toxic synthetic chemical acaricides and might prove a valuable component of integrated tick management strategies.

Histopathological and morphological studies on natural Cysticercus fasciolaris infection in liver of Wistar rats.

Descriptive morphology of multifocal hepatic cysts found in eight of forty five (17.78 %) Wistar rats sacrificed during pharmacological studies related to herbal formulations was studied. The creamish to white cysts were of varying sizes, ranging from 3-8 mm in diameter. Morphological studies of these cysts depicted the presence of metacestodes of Taenia taeniaeformis i.e. Cysticercus fasciolaris inside them. The scolex of metacestode revealed four suckers and rostellum armed with two distinct rows of characteristic pen knife shaped hooks (characteristics of taeniid cestodes). The average size of large hooks was 392.92 ± 10.12 µ and that of small hooks was 240.64 ± 14.26 µ. The average size of suckers was 304.36 ± 12.33 µ. Histopathology of hepatic tissue surrounding the cysts revealed zones of fatty change, inflammation, granulation tissue and metaplasia. However, the histopathology of stomach and small intestines didn't show any significant lesions.

In vitro acaricidal activity of Murraya koenigii (L.) Spreng (Rutaceae) extracts against synthetic pyrethroid-resistant Rhipicephalus (Boophilus) microplus.

Larval packet test was used for detection of resistance status against cypermethrin and deltamethrin, the most commonly used synthetic pyrethroids in Rhipicephalus (Boophilus) microplus collected from Faridkot district, Punjab (India). The slope of mortality, lethal concentration for 50 % (LC50) and resistance levels were determined from the regression graphs of probit mortality of ticks plotted against log values of increasing concentrations of cypermethrin and deltamethrin. Results indicated presence of resistance of levels I and II against cypermethrin (resistance factor (RF) = 2.82) and deltamethrin (RF = 8.44), respectively. Adult immersion test was used to assess the acaricidal activity of aqueous (MLAq), ethanol (MLE), chloroform (MLC), acetone (MLA) and hexane (MLH) extracts of leaves of Murraya koenigii against these synthetic pyrethroid (SP)-resistant engorged adult females of R. (B.) microplus by determination of per cent adult mortality, reproductive index (RI), per cent inhibition of oviposition (%IO) and hatching rate. The per cent mortality caused by various extracts at concentrations ranging from 0.625 to 10.0% varied from 0.0 to 100.0% with maximum per cent mortality of 10.0, 100.0, 70.0, 40.0 and 10.0 recorded against MLAq, MLE, MLC, MLA and MLH, respectively. Among all extracts, the highest acaricidal property against SP-resistant R. (B.) microplus was exhibited by the MLE as it showed the minimum LC50 [95% confidence limit (CL)] values of 2.97% (2.82-3.12%), followed by MLC as 10.26% (8.84-11.91 %) and MLA as 18.22% (16.18-20.52%). The average egg mass weight recorded in live ticks treated with various concentrations of different extracts was lower than the respective control group ticks and was significantly (p < 0.01) lower in ticks treated with MLH extract. However, no significant effect on hatchability of eggs of treated groups when compared to control was recorded. A significant (p < 0.05) decrease in the RI was recorded in MLH extract-treated ticks, and the %IO varied from 0.07 to 34.73% with various extracts and was recorded maximum with highest concentration of MLH. The results of the current study indicate that the extracts of M. koenigii can be used for control of SP-resistant ticks.

Pharmacokinetic-pharmacodynamic integration of enrofloxacin and its metabolite ciprofloxacin in buffalo calves.

The present study was planned with an objective to test the pharmacokinetics of a new formulation of enrofloxacin (Flobac® SA) in buffalo calves. The drug was administered at the dose rate of 7.5 mg kg-1 body weight through the intravenous (i.v.) and intramuscular (i.m.) route followed by plasma collection and analysis at different time intervals. After analysis, using High Performance Liquid Chromatography - Ultraviolet, various pharmacokinetic parameters were calculated using visual fit for compartmental analysis, followed by integration with pharmacodynamic parameters against Escherichia coli and Pasteurella multocida. Although total area under plasma drug concentration time curve was higher through the i.v. route, mean residence time and metabolic conversion ratio was higher following administration by the i.m. route indicating longer persistence of the drug in body. Overall i.m. bioavailability of the parent compound with its metabolite was found to be 91%. Upon, Pharmacokinetic-Pharmacodynamic integration, all the parameters indicated significant antibacterial activity. It can be concluded that the dose of enrofloxacin used in the present study can be administered to contain infections caused by P. multocida and E. coli in buffalo calves.

Evaluation of ameliorative potential of selenium on carbendazim induced oxidative stress in male goats.

In the present investigation, ameliorative effect of selenium on carbendazim induced oral sub chronic toxicity in bucks was assessed by studying various indices of antioxidant defense system. Bucks were randomly divided into four groups of four animals each. Group I served as control, Group II was orally drenched carbendazim at the dose rate of 50mg/kg body weight for 90 consecutive days. Group III was orally administered selenium in the form of sodium selenite at the dose rate of 0.05mg/kg body weight for 90 consecutive days. Group IV was orally administered carbendazim along with selenium at the same dosages as Group II and III. Prolonged administration of carbendazim produced oxidative stress in goat bucks as evidenced by increase in lipid peroxidation and decline in total antioxidant capacity. The increase in the activity of antioxidant enzymes was not sufficient to prevent pesticide induced oxidative stress. Selenium supplementation provides some amelioration against this effect. Further study is needed to prove ameliorative potential of this antioxidant against carbendazim induced toxicity in goat bucks.