Antifertility effects of quinestrol in male lesser bandicoot rat, Bandicota bengalensis, and potential in managing rodent population under field conditions.

Integrating fertility control techniques using steroid hormones after lethal control can help reduce post control rebuildup of rodent populations. The current study is the first to assess the antifertility effects of quinestrol in male lesser bandicoot rat, Bandicota bengalensis which is the predominant rodent pest species in Southeast Asia. Rats in different groups were fed bait containing 0.00%, 0.01%, 0.02%, and 0.03% quinestrol for 10 days in laboratory and evaluated immediately, and 15, 30, and 60 days after treatment discontinuation for effect on reproduction and other antifertility parameters. Effect of 0.03% quinestrol treatment for 15 days was also observed in managing rodent populations in groundnut crop fields. Treatment resulted in average consumption of 19.53 ± 1.80, 67.63 ± 5.50, and 246.67 ± 1.78 mg/kg bwt active ingredient by three treated groups of rats, respectively. No reproduction was observed in female rats mated with male rats treated with 0.03% quinestrol, even 30 days after cessation of treatment. Post-mortem examination showed a significant (P < 0.0001) effect of treatment on organ weights (testis, cauda epididymis, seminal vesicles, and prostate gland) and different sperm parameters (sperm motility, sperm viability, sperm count, and sperm abnormality) in the cauda epididymal fluid with partial reversibility after 60 days. A significant (P < 0.0001) effect of quinestrol on the histomorphology of testis and cauda epididymis was observed, suggesting its effect on spermatogenesis. Affected cell association and cell count in seminiferous tubules did not fully recover within 60 days of stopping treatment. Evaluation of the effects of quinestrol treatment in groundnut fields showed greater reductions in rodent activity in fields treated with 2% zinc phosphide followed by 0.03% quinestrol treatment as compared to fields treated with 2% zinc phosphide alone. Research concludes that quinestrol has the potential to reduce fecundity and post control rebuildup of B. bengalensis populations, but long-term studies of the effectiveness of quinestrol under large-scale field conditions are needed to use it as part of an integrated pest control program for rodents.

Formulation and evaluation of solid lipid nanoparticles loaded with papaya seed chloroform extract for long-term antifertility effects on the male rat, Bandicota bengalensis.

The study is the first to formulate and investigate potential of papaya seed chloroform extract based solid lipid nanoparticles (PSCEN) as antifertility agents on male Bandicota bengalensis. The prepared nanoparticles were spherical of size 300-600 nm. The release kinetics showed a controlled release of the drug with major release over 48 h. To assess the antifertility effects of PSCEN, adult male rats were fed a diet containing two different concentrations of PSCEN (5% and 10%) for 15 days under bi-choice conditions. The mean total active ingredient ingestion of the rats in the two treated groups ranged from 2.13-3.31 and 3.92-5.87 g/100g body weight, respectively. No adverse effects of treatment on body weight were observed. Also, no mortality of rats was observed. The treatment had a significant effect on the weight of the testis and the epididymis, but not on the other organs. Sperm motility (%), sperm viability (%), sperm count (millions/ml), sperm mitochondrial activity (%), sperm nuclear chromatin de-condensation (%) and sperm hypo-osmotic swelling (%) were significantly decreased, and sperm abnormality (%) significantly increased compared to the vehicle control group. The reproductive success rates of male rats treated with 5% and 10% PSCEN and mated with untreated female rats were 20.00-66.67% and 16.67%, respectively, while in untreated female rats mated with male rats of vehicle control group, reproductive success rate was 33.33 to 80%. The study found a maximal antifertility effect of the 10% PSCEN containing bait, which was irreversible up to 105 days after stopping treatment, suggesting long-term efficacy.

Antireproductive changes instigated by efficient drug delivery via papaya seed chloroform extract-based nanoparticles in male rat Bandicota bengalensis.

Anti-reproductive potential of papaya seed chloroform extract-based solid lipid nanoparticles (PSCEN) was investigated for the first time in lesser bandicoot rat, Bandicota bengalensis. Mature male rats (n = 30 per group) were fed bait (loose mixture of cracked wheat, powdered sugar, and groundnut oil in the ratio 88:10:2) containing two different concentrations of PSCEN (5% and 10%) in a bi-choice condition for 15 days with one group as vehicle control. The ingestion of active ingredient in 15 days treatment was significantly (P ≤ 0.05) higher by rats treated with 10% PSCEN (39.17-58.70 g/kg body weight) as compared to rats treated with 5% PSCEN (21.30-33.23 g/kg body weight). A dose dependent significant (P ≤ 0.05) decrease was observed in the level of testosterone, FSH, LH and GnRH in plasma of treated rats. A significant (P ≤ 0.05) decrease was also observed in level of total soluble proteins, total lipids, phospholipids and cholesterol in both plasma and testicular tissue, and level of 17ß-HSD and 3ß-HSD in testicular tissue indicating anti-reproductive effects of PSCEN treatment. There was observed significant (P ≤ 0.05) effect of treatment on histomorphology of testis and cauda epididymis in the form of reduced tubular diameter, germinal epithelial thickness, number of germ cells and dissociation of epithelial cycle in seminiferous tubules, and reduced tubular diameter, increased epithelial thickness, vacuolization, loose contact of principle cells and reduced number of spermatozoa in the cauda epididymal tubules. Maximum antifertility effect was observed with 10% PSCEN treatment, which was not reversed upto 105 days of treatment withdrawal indicating long-term efficacy. The current investigation suggests the use of PSCEN in the management of reproduction of B. bengalensis by exerting influence on testicular and cauda epididymal functions and biochemical parameters.

Severe Infection of Nippostrongylus brasiliensis in Bandicota bengalensis Inhabiting Commensal Areas of Punjab, India: Prevalence, Risk Factor Analysis, Molecular Identification and Phylogenesis.

PURPOSE: The present study aimed to record the prevalence, risk factors, molecular identification, and phylogeny of Nippostrongylus brasiliensis found in the small intestine of the lesser bandicoot rat, Bandicota bengalensis, a wild rodent species. METHODS: A total of 100 bandicoot rats live trapped at two commensal urban locations (50 each), i.e., a fish market and railway station, in Ludhiana, Punjab State (India), from November 2020 to October 2021, were analysed for the presence of N. brasiliensis, a nematode parasite of zoonotic importance. RESULT: Overall, the small intestine of 43.00% of the rats was found severely infected with bright red coloured adult N. brasiliensis of both sexes (total of 1439 specimens). Faecal samples contained ellipsoidal and thin-shelled eggs measuring 62.25-74.70 m in length and 33.20-37.35 m in breadth. No significant (P > 0.05) effect of host age, sex, or season was observed on the rate of infection. The parasite intensity and mean abundance ranged from 27.68-38.04 and 10.52-18.26, respectively, indicating a high risk of disease transmission. Based on the morphology, the nematode parasite was identified as Nippostrongylus sp. Molecular identification was confirmed through PCR amplification of the mitochondrial cytochrome oxidase I gene, which showed a single band of approximately 355 bp. A comparison of the present isolate with the available sequences of Nippostrongylus species across the globe showed 100% nucleotide homology with N. brasiliensis sequences available in GenBank from Japan (AP017690), the USA (U57035), and New Zealand (NC033886). CONCLUSION: The study indicates that B. bengalensis inhabiting commensal urban areas is a reservoir host for N. brasiliensis, which if transmitted to humans and animals visiting the area may pose a potential health risk. The study thus suggests proper rodent population management close to human habitations to avoid the transmission of disease-causing agents.

Baseline Assessment of Evidence-Based Intrapartum Care Practices in Medical Schools in 3 States in India: A Mixed-Methods Study.

INTRODUCTION: Implementation research with pre- and post-comparison was planned to improve the quality of evidence-based intrapartum care services in Indian medical schools. We present the baseline study results to assess the status of adherence to intrapartum evidence-based practices (IP-EBP) in study schools in 3 states in India and the perception of the faculty. METHODS: A concurrent mixed-methods approach was used to conduct the baseline assessment in 9 medical schools in Rajasthan, Gujarat, and Union Territory from October 2018 to June 2019. IP-EBP among pregnant women in uncomplicated first (n=135), second (n=120), and third stage (n=120) of labor were observed using a predesigned, pretested checklist quantitatively. We conducted in-depth interviews with 33 obstetrics and gynecology faculty to understand their perceptions of intrapartum practices. Quantitative data were analyzed using SPSS (version 22). COM-B (Capability, Opportunity, and Motivation Behavior) model was used to understand the behaviors, and thematic analysis was done for the qualitative data. FINDINGS: Unindicated augmentation of labor was done in 64.4%, fundal pressure applied in 50.8%, episiotomy done in 58.3%, and delivery in lithotomy position was performed in 86.7% of women in labor. CONCLUSIONS: Intrapartum practices that are not recommended were routinely practiced in the study medical schools due to a lack of staff awareness of evidence-based practices and incorrect beliefs about their impact.

Effect of quinestrol on body weight, vital organs, biochemicals and genotoxicity in adult male lesser bandicoot rat, Bandicota bengalensis.

The present study was aimed to evaluate the toxic effects of quinestrol (a synthetic estradiol) in male lesser bandicoot rat, Bandicota bengalensis. Effect was studied on body weight, weight of vital organs, changes in level of biochemical parameters and genotoxicity. Feeding of bait containing 0.01% quinestrol in bi-choice and 0.02 and 0.03% quinestrol in no-choice for a period of 10 days resulted in total ingestion of 19.50, 67.60 and 243.30 mg/kg bwt, respectively of the active ingredient. Autopsy of rats after 15 and 30 days of treatment withdrawal revealed no significant effect on body weight and weights of vital organs of rats. A significant decrease in the testicular levels of 17-beta hydroxysteroid dehydrogenase and increase in total soluble proteins was observed in rats treated with 0.02 and 0.03% quinestrol. The plasma levels of lipid peroxidation in the form of malondialdehyde concentration and lactate dehydrogenase increased significantly whereas the level of testosterone decreased significantly in treated rats. The plasma levels of acid and alkaline phosphatases, superoxide dismutase and total proteins differed non-significantly among rats of treated and untreated groups. The effect was found reversed partially in rats autopsied after 60 days of treatment withdrawal. No micronuclei in bone marrow cells, no aberrations in chromosomes and no DNA damage in blood cells during comet assay indicated no genotoxic effect of quinestrol on B. bengalensis at the test doses administered. The results thus revealed that quinestrol causes reversible toxic effects in the form of oxidative stress, increased lytic enzyme activity and decreased steroidogenesis which may further lead to testicular damage thereby inhibiting reproductive function. Also more effect was shown at higher doses ingested in no-choice test as compared to low doses ingested in bi-choice tests.

Studies on bromadiolone resistance in Rattus rattus populations from Punjab, India.

There are several reports on development of resistance to bromadiolone in different species of rodents around the globe, however, there is no such report involving systematic study from India. Hence, present study was carried out to investigate current status of bromadiolone resistance in house rat (Rattus rattus; n=154) collected from different poultry farms (n=8) based on feeding test, blood clotting response (BCR) test and molecular characterization of VKORC1 gene. Based on feeding test and BCR test, 28% rats were suspected to be resistant. Molecular analysis of VKORC1 gene of four suspected to be resistant rats having Prothrombin Time (PT) <70s, International Normalized Ratio (INR) <4.0 and died between 26 and 73days after treatment revealed no single nucleotide polymorphism (SNP) in nucleotide sequences. None of the sample under study showed complete nucleotide homology with previously reported nucleotide sequences of R. rattus. The sequences of VKORC1 gene under study can thus be considered as the novel sequences. Present investigation on molecular characterization of VKORC1 gene did not reveal any genetic resistance in Rattus rattus population against bromadiolone though rats could be considered resistant based on BCR and feeding tests.

Histomorphological and biochemical changes induced by triptolide treatment in male lesser bandicoot rat, Bandicota bengalensis.

Mature and healthy male lesser bandicoot rats, Bandicota bengalensis (n = 40) were fed on bait (mixture of cracked wheat and powdered sugar in 98:2) containing different concentrations of triptolide (0, 0.15, 0.20 and 0.25% w/w) for 15 days in two-choice trials. Results revealed no significant effect of triptolide treatment on weights of vital organs after 30 and 60 days of treatment withdrawal. A significant (P ≤ 0.05) increase in plasma levels of TP, ALP, ACP, ALT and AST in response to stress induced in groups of rats treated with 0.20 and 0.25% triptolide was observed after 30 days of treatment withdrawal. No significant effect of treatment was observed on histomorphology of liver. A significant (P ≤ 0.05) effect of triptolide treatment was, however, observed on testicular function in the form of reduced diameter of seminiferous tubules and number of various spermatogenic cells indicating effect on spermatogenesis and spermiogenesis. The cell stages affected did not recover fully within 60 days period following treatment withdrawal. The present study suggests the potential of triptolide in the reproductive management of B. bengalensis by way of affecting testicular function.

Reproductive toxicity of triptolide in male house rat, Rattus rattus.

The aim of study was to investigate the toxic effect of triptolide fed in bait on reproduction of male house rat, Rattus rattus. Feeding of cereal based bait containing 0.2% triptolide to male R. rattus for 5 days in no-choice feeding test, leading to mean daily ingestion of 20.45 mg/kg bw of triptolide, was found effective in significantly (P ≤ 0.05) reducing sperm motility and viability in cauda epididymal fluid by 80.65 and 75.14%, respectively, from that of untreated rats. Pregnancy rates were decreased by 100% in untreated cyclic female rats paired with male rats treated with 0.2% triptolide. Present studies suggest the potential of 0.2% triptolide bait in regulating reproductive output of R. rattus.

Poultry egg components as cereal bait additives for enhancing rodenticide based control success and trap index of house rat, Rattus rattus.

OBJECTIVE: To compare the acceptance and efficacy of cereal bait containing different concentrations of poultry egg components in laboratory and poultry farms to control house rat, Rattus rattus (R. rattus). METHODS: Acceptance of cereal bait containing different concentrations (2%, 5% and 10%) of poultry egg components such as egg shell powder (ESP), egg albumin (EA) and crushed egg shell as bait additives were studied after exposing them to different groups of rats in bi-choice with bait without additive. Behaviour of rats towards cereal bait containing 2% concentration of different egg components was recorded in no-choice conditions through Food Scale Consumption Monitor. In poultry farm predominantly infested with R. rattus, acceptance and efficacy of 2% zinc phosphide bait containing 2% EA and ESP was evaluated. Trap success of single rat traps containing chapatti pieces smeared with 2% EA and 2% ESP was also evaluated in poultry farm. RESULTS: In bi-choice tests, significantly (P<0.05) higher preference was observed for baits containing 2% and 5% ESP and all the three concentrations of EA compared to plain bait by female rats and that of baits containing 5% and 10% EA by male rats. In no-choice test, non-significantly higher consumption, number of bouts made and time spent towards bait containing 2% EA was found by rats of both sexes. In poultry farm, acceptance and efficacy of 2% zinc phosphide bait containing 2% EA and ESP was significantly (P<0.05) more than 2% zinc phosphide bait without additive. No significant difference was, however, found in trap success of single rat traps containing chapatti pieces smeared with 2% concentration of EA and ESP placed in the poultry farm. CONCLUSIONS: Present data support the use of 2% egg albumin and egg shell powder in cereal bait to enhance acceptance and efficacy of 2% zinc phosphide bait against R. rattus. This may further help in checking the spread of rodent borne diseases to animals and humans.

Potential of eucalyptus oil as repellent against house rat, Rattus rattus.

Rodent repellents are chemicals which by taste or odour or possibly by both will prevent animal from feeding or gnawing. Such substances may be used in protecting an area from rodent infestation or in protecting packaged food, packing materials, electric cables, and other important vulnerable materials. Mature and healthy house rat, Rattus rattus of both sexes, was exposed to 5, 10, and 20% eucalyptus oil applied as spray in laboratory pens in bichoice tests. Each concentration was applied through three different modes of application, that is, daily, once, and alternatively in a week. Repellent effect of the oil was assessed based on food consumption from treated and untreated sides for four days. In overall, food consumption was significantly (P < 0.0001) low from treatment side compared to the untreated side indicating significant repellent effect of the oil at all the three concentrations tested. Repellent effect of the oil was, however, not found to differ significantly between the two sexes. Percent repellency in both male and female rats was apparently more with daily application of 5 and 10% eucalyptus oil. Present studies reveal the potential of eucalyptus oil in repelling away R. rattus; however, further studies may be conducted to enhance the persistence of repellent effect for longer period of time.

Effect of triptolide on reproduction of female lesser bandicoot rat, Bandicota bengalensis.

Triptolide has been reported to cause antifertility in male rats and mice. However, studies on female rats have been limited. Present study was aimed to evaluate the effects of triptolide on reproduction of wild female rodent pest species, Bandicota bengalensis. Feeding of bait containing 0.1, 0.15 and 0.2% triptolide for a period of 15 days in bi-choice resulted in per day ingestion of 17.37, 23.54 and 27.49 mg/kg body weight of triptolide, respectively. Examination of vaginal smear of all the rats revealed a significant (p ≤ 0.05) increase in duration of estrous cycle due to increase in durations of metestrous and diestrous stages in rats of treated groups. Autopsy of rats after 15 and 30 days of treatment withdrawal revealed significant (p ≤ 0.05) reduction in weights of uterus and ovaries, non-significant reduction in weights of liver and levels of estradiol and progesterone and significant (p ≤ 0.05) reduction in levels of urea and BUN and increase in levels of plasma proteins, ALT, AST, ALP, ACP and LDH in rats of treated groups compared to untreated group. There was no significant (p ≤ 0.05) effect of treatment on body weight. Triptolide treatment affected the histomorphology of uterus by causing a decrease in lumen and columnar cell height and number of uterine glands and ovary by increasing the number of atretic follicles and decreasing the number of developing follicles. The present study suggests triptolide to be a strong candidate affecting reproduction of female B. bengalensis.

Potential of triptolide in reproductive management of the house rat, Rattus rattus.

Mature and healthy male house rats, Rattus rattus (n= 160) were fed on bait (cracked wheat: powdered sugar, 98:2) containing different concentrations of triptolide (0.1, 0.05, 0.025 and 0%) for 7 and 14 days in no-choice and bi-choice feeding tests in the laboratory. The objective of the study was to record the antifertility affects of triptolide after 30 and 60 days of termination of treatment. Results revealed no significant effect of triptolide treatment on weights of testis, epididymis, seminal vesicles and prostate gland of rats. Overall, sperm motility, live sperm count, sperm density and sperm morphology in the cauda epididymal fluid were found to differ significantly (P≤ 0.05) between untreated and treated groups of rats. The major effect of triptolide on sperm morphology was in the form of sperm head tail separation, which was up to 56.0% in rats treated for 14 days in no-choice and autopsied after 30 days. A significant effect (P≤ 0.05) of triptolide treatment was observed on the histomorphology of the testis, which included a dose-dependent decrease in diameter of seminiferous tubules, thickness of germinal epithelium and numbers of various spermatogenic cells. Cell associations in the seminiferous epithelial cycle were poorly developed in rats ingesting medium (4.7-5.1 mg/100 g bw) and high doses (6.9-7.2 mg/100 g bw) of triptolide than rats ingesting low doses (1.8-2.3 mg/100 g bw) and untreated rats. The cell stages affected had not recovered fully within the 60 day period following triptolide withdrawal. The present study suggests the potential of triptolide in reproductive management of Rattus rattus.

Pathological alterations in natural cases of Capillaria hepatica infection alone and in concurrence with Cysticercus fasciolaris in Bandicota bengalensis.

The present study reports the natural occurrence and pathomorphological alterations of Capillaria hepatica infection alone and in concurrence with Cysticercus fasciolaris infection in the liver of Bandicota bengalensis. Out of the eighteen mature male B. bengalensis autopsied, livers of eight rats (44.4 %) were found infected with parasites comprising two (11.1 %) rats infected with C. hepatica alone, four (22.2 %) infected with C. fasciolaris alone and two (11.1 %) infected with C. hepatica in concurrence with C. fasciolaris. Gross lesions comprising of pale cystic areas or streaks on the surface of liver in rats revealed the presence of eggs of C. hepatica scattered in the parenchyma of the liver. Histologically, granulomatous reaction around the eggs, adult worms and dead components of parasites were observed.

Rodents as reservoirs of parasites in India.

We monitored the prevalence of endoparasitic infections of rodents in Punjab State, India, between January 2004 and December 2005. Three species of wild rodents, namely the house rat, Rattus rattus (n= 42), the lesser bandicoot rat, Bandicota bengalensis (n= 34) and the Indian gerbil, Tatera indica (n= 15), were live-captured from houses and crop fields. Examination of various organs revealed that the highest rates of endoparasitic infection occurred in R. rattus (40.5%), followed by B. bengalensis (35.3 %) and then T. indica (20.0%), with an overall infection rate of 35.2%. All three rodent species were found naturally infected with one or more species of helminths. Metacestodes (1-6) of Cysticercus fasciolaris (larvae of Taenia taeniaeformis) were found in all three rodent species (in the liver). In one male T. indica, numerous robust T. taeniaeformis metacestodes were found in oval sacs attached to the mesentery and the abdominal wall, an unusual site. The cauda epididymal fluid of the same gerbil was also found to be infected with a very rare species of strongylid nematode, which could not be identified to genus or species level. It is possible that this nematode is transmitted sexually and thus may affect the reproductive potential of gerbils. This appears to be the first report of this phenomenon. In one B. bengalensis individual, the intestine was found to be obstructed with an acanthocephalan, Moniliformis moniliformis, with concurrent infection with C. fasciolaris in the form of multiple cysts in the liver. Although no natural protozoan infection was found in these field rodents, experimental Trypanosoma evansi infection has been established in all three species with high pathogenicity, and the possibility of sexual transmission was supported by the presence of T. evansi in the cauda epididymal fluid of male rats.