Unilateral retrobulbar haemorrhage in a cat secondary to suspected anticoagulant rodenticide intoxication.

A 6-month-old intact female mixed-breed kitten presented with severe exophthalmos of the left eye. Periocular lesions, including subconjunctival haemorrhage, third eyelid protrusion, and left eyelid oedema, were detected in the absence of globe retropulsion. The left intraocular pressure was increased, and ocular ultrasonography revealed ipsilateral retrobulbar fluid. Coagulation panels were markedly prolonged and severe anaemia was detected. Ultrasound-guided retrobulbar centesis performed to decrease intraocular pressure yielded blood. Based on the history and clinical findings, anticoagulant rodenticide intoxication was suspected. Treatment included partial tarsorrhaphy and the administration of topical antibiotics, artificial tears, and vitamin K1. Fresh whole blood and fresh frozen plasma were transfused for supportive therapy. Coagulation parameters improved after 7 days of hospitalisation. The periocular lesions resolved within 14 days, despite persistent optic nerve damage and blindness. This case report raises the possibility that anticoagulant rodenticide toxicity may result in retrobulbar haemorrhage in the absence of other typical cavitary bleeding. Although uncommon, anticoagulant rodenticide toxicity should be considered in cats with retrobulbar haemorrhage.

The Enigma of Norbormide, a Rattus-Selective Toxicant.

Norbormide (NRB) is a Rattus-selective toxicant, which was serendipitously discovered in 1964 and formerly marketed as an eco-friendly rodenticide that was deemed harmless to non-Rattus species. However, due to inconsistent efficacy and the emergence of second-generation anticoagulants, its usage declined, with registration lapsing in 2003. NRBs' lethal action in rats entails irreversible vasoconstriction of peripheral arteries, likely inducing cardiac damage: however, the precise chain of events leading to fatality and the target organs involved remain elusive. This unique contractile effect is exclusive to rat arteries and is induced solely by the endo isomers of NRB, hinting at a specific receptor involvement. Understanding NRB's mechanism of action is crucial for developing species-selective toxicants as alternatives to the broad-spectrum ones currently in use. Recent research efforts have focused on elucidating its cellular mechanisms and sites of action using novel NRB derivatives. The key findings are as follows: NRB selectively opens the rat mitochondrial permeability transition pore, which may be a factor that contributes to its lethal effect; it inhibits rat vascular KATP channels, which potentially controls its Rattus-selective vasoconstricting activity; and it possesses intracellular binding sites in both sensitive and insensitive cells, as revealed by fluorescent derivatives. These studies have led to the development of a prodrug with enhanced pharmacokinetic and toxicological profiles, which is currently undergoing registration as a novel efficacious eco-sustainable Rattus-selective toxicant. The NRB-fluorescent derivatives also show promise as non-toxic probes for intracellular organelle labelling. This review documents in more detail these developments and their implications.

The New South Wales Mouse Plague 2020-2021: A One Health description.

A mouse plague occurred in Eastern Australia from spring 2020 to winter 2021, impacting an area of around 180,000 km2. It harmed human physical and psychological health, damaged the natural and built environment, and endangered farmed, domestic and native animals. However, the mouse plague was overshadowed by the COVID-19 pandemic, especially as the end of the plague coincided with the arrival and surge of the COVID-19 delta strain in rural New South Wales (NSW). In this article, we systematically overview the multiple impacts of the plague and highlight their complex interactions. Using a One Health framework, we comprehensively review the i) human, ii) animal and iii) environmental impacts including economic dimensions. Given the damage that the mouse plague caused to infrastructure, we consider the environment from two perspectives: the natural and the built environment. This One Health description of the 2020-2021 mouse plague identifies priorities for preparedness, response and recovery at local, regional land levels to inform response and management of future mouse plague events in Australia. It also highlights the need for ongoing collaboration between researchers and practitioners in the human, animal and environmental health sectors.

Alpha-chloralose poisoning in 25 cats: clinical picture and evaluation of treatment with intravenous lipid emulsion.

OBJECTIVES: The aims of this study were to describe the clinical picture and progression in cats with alpha-chloralose (AC) intoxication and to determine if treatment with intravenous (IV) lipid emulsion (ILE) influenced either the serum concentration of AC or the clinical signs. METHODS: Cats with suspected AC poisoning admitted to a university small animal hospital were included. The cats were randomised into two groups: one receiving 20% ILE at a dose of 300 mg/kg as a 2 min bolus, followed by a 1500 mg/kg continuous rate infusion over 30 mins (IL+ group) and the other receiving IV fluid therapy with Ringer's acetate (IL- group). Serum samples were drawn at 0, 2, 12 and 24 h after admission. Samples were tested for AC with a novel validated, quantitative, ultra-high-performance liquid chromatography-tandem mass spectrometry method. Vital and predefined clinical signs were noted at the times of sampling and patients were scored using a previously described intoxication severity score. Telephone interviews were conducted after discharge to assess outcome. RESULTS: A total of 25 cats were enrolled: 13 cats in the IL+ group and 12 in the IL- group. The most common clinical signs at presentation were tremor (n = 22, 88.0%), cranial nerve deficits (n = 20, 80.0%) and bradycardia (n = 19, 76.0%). No significant difference in AC concentration or change in intoxication score over time was found between the IL+ and IL- groups at any time point (P >0.05). All cats recovered within 72 h. CONCLUSIONS AND RELEVANCE: ILE did not have any effect on the AC serum concentration or clinical signs in AC-poisoned cats. All cats survived until follow-up. In cats with an acute onset of the described neurological signs, AC intoxication is an important differential diagnosis with an excellent prognosis.

A strategy to improve rodent control while reducing rodenticide release into the environment.

In addition to having a negative impact on the health of people and domestic animals, rodents often cause enormous damage to the environment by disrupting natural biodiversity. The negative impacts of rodents in urban and rural areas have required intensive use of rodentcides in spite of the proven risk of secondary poisoning of non-target predators and scavengers. Continuous and intensive use of rodenticides has led to environmental pollution through their retention in the environment. Commensal rodents are predominantly managed with anticoagulant rodenticides, which are very persistent in the environment and move up the food chain and accumulate in the bodies of predators and scavengers. Generally, the use of anticoagulant rodenticides continues, and there is a need to take appropriate measures to reduce their harmful impact. The efficacy of second generation anticoagulants (bromadiolone, difenacoum and brodifacoum), combined either mutually or with chlorophacinone at reduced doses (0.001 % and 0.0008 %), in controlling brown rats (Rattus norvegicus) was tested in a four-day no-choice feeding test. Combinations of second generation anticoagulants were more effective than the combination of chlorophacinone and second generation anticoagulants. The results indicate that combinations of different anticoagulants at multifold lower doses than the standard may provide a successful tool for brown rat control and a more environment-friendly method of rodent control and protection of non-target animals.

Assessing the clinical efficacy of low-volume therapeutic plasma exchange in achieving recovery from acute liver failure induced by yellow phosphorous poisoning.

BACKGROUND: Acute liver failure (ALF) following yellow phosphorous (YP) ingestion is similar to acetaminophen-induced ALF and it has become a public concern in our region. This study assessed low volume therapeutic plasma exchange (LV-TPE) efficacy in improving the transplant free survival in YP poisoning. METHODS: Adult patients with toxicology reports of YP and ALF requiring critical care were included in the study. LV-TPE was planned for three consecutive days and three more if required. Performed 1.3 to 1.5 plasma volume replacing with 0.9% normal saline, 5% human albumin solution, and fresh frozen plasma based on ASFA 2019 criteria. MELD score, laboratory parameters, LV-TPE details were captured. The study end point was clinical outcome of the patients. RESULTS: Among 36 patients, 19 underwent LV-TPE and 17 opted out of LV-TPE and they were included as a control arm. The MELD score was 32.64 ± 8.05 and 37.83 ± 9.37 in both groups. There were 13 survivors in LV-TPE group leading to a 68.42% reduction in mortality. The coagulation and biochemical parameters showed a significant percentage change after LV-TPE. Refractory shock, delay in initiating procedure and acidosis were independent predictors of mortality. CONCLUSION: A well-timed LV-TPE improves the survival of patients with ALF due to YP poisoning.

Phytochemical and GC-MS analysis of Thevetia peruviana fruit methanol extract as an anti-rodenticide potential against balb C rats.

Rodents have remained a menace to humans, hence there is need to evaluate for anti-rodent activity of cheap and environment friendly control methods. This study aimed at evaluating the anti-rodenticidal activity of Thevetia (T.) peruviana fruit methanol extract. T. peruviana fruit was sampled, dried and extracted using methanol/water in the ratio of 3:1 by volume. Phytochemicals; alkaloids, phenols, flavonoids, glycosides, saponins, and tannins were determined qualitatively and quantitatively in the fruit extract. The extract was then characterized using Fourier Transform Infrared (FTIR) and Gas Chromatography Mass Spectrophotometer (GC-MS). Anti-rodent activity of the extracts was determined on a total of 25 mice with body weights of 20-25 g. The animals 8-12 weeks' old were grouped into 5 cages (5 animals per cage), marked and allowed to acclimatize with laboratory conditions of 25 °C, warm or less humid for 5 days with enough water and food. Extract dose (between 0.3 and 0.5 g of extract/kg body weight) was then administered in a single dose by gavage using intubation canula for 7 days and the animals observed for any toxicity and mortality. The data was subjected to probit analysis and ANOVA. Phytochemical screening showed that the extracts contained glycosides, phenols, saponins, alkaloids, triterpenoids, and flavonoids in different abundance. T. peruviana fruit contained 125.13 ± 1.04 mg/g in GAE phenolic content, 85.70 mg/g in RE of dry weight of flavonoids, 10.50 ± 0.01 mg/g in TAE of Tannins, 16.50± 0.21 mg/g alkaloid content, and 8.28± 0.11 mg/g saponin content. The FTIR spectrophotometer depicted O - H, CH2, C[bond, double bond]O, C-O-C functional groups in wave numbers of 3335, 2932, 1599, and 1001 cm-1 respectively. The T. peruviana fruit methanol extracts depicted high acute toxicity with an average of 300 mg/kg upon oral administration in Balb C mice species. The fruit extract from T. peruviana revealed presence of alkaloids, phenols, glycosides, saponins, tannins. These participated synergistically in killing the rats and the postmortem examination report indicated that the tested extract induced a number of physical changes in the mice and therefore the T. peruviana's fruit extract can be utilized as a natural alternative anti-rodent in agriculture production before and after harvesting.

Anticoagulant rodenticide poisoning in farmed Patagonian mara (Dolichotis patagonum).

BACKGROUND: Anticoagulant rodenticide (AR) poisoning was diagnosed in 3 Patagonian maras (Dolichotis patagonum) raised in the mara farm in Thailand. To date, there have been no reports of maras with diagnosed AR poisoning. CASE PRESENTATION: The first clinical sign of the sickening maras was anorexia. Fifteen from 50 maras were dead over a 3-5 day period after the clinical signs had occurred. Positive results to AR were detected in all of the maras' liver specimens by screening test using thin layer chromatography and spectrophotometry methods. Supportive therapy was selected for the treatment of the 35 surviving maras. During the follow - up observation period of 12 months, all of the surviving maras were healthy and no reproductive loss. CONCLUSIONS: This is the first report on suspected AR poisoning in maras in Thailand based on history taking, clinical signs, gross pathology lesions and chemical analysis. AR poisoning in the present report is possibly from contaminated animal food. Therefore, quality control of food should be fastidious when feeding maras.

First evidence of widespread positivity to anticoagulant rodenticides in grey wolves (Canis lupus).

Second-generation Anticoagulant Rodenticides (ARs) can be critical for carnivores, due to their widespread use and impacts. However, although many studies explored the impacts of ARs on small and mesocarnivores, none assessed the extent to which they could contaminate large carnivores in anthropized landscapes. We filled this gap by exploring spatiotemporal trends in grey wolf (Canis lupus) exposure to ARs in central and northern Italy, by subjecting a large sample of dead wolves (n = 186) to the LC-MS/MS method. Most wolves (n = 115/186, 61.8 %) tested positive for ARs (1 compound, n = 36; 2 compounds, n = 47; 3 compounds, n = 16; 4 or more compounds, n = 16). Bromadiolone, brodifacoum and difenacoum, were the most common compounds, with brodifacoum and bromadiolone being the ARs that co-occurred the most (n = 61). Both the probability of testing positive for multiple ARs and the concentration of brodifacoum, and bromadiolone in the liver, systematically increased in wolves that were found at more anthropized sites. Moreover, wolves became more likely to test positive for ARs through time, particularly after 2020. Our results underline that rodent control, based on ARs, increases the risks of unintentional poisoning of non-target wildlife. However, this risk does not only involve small and mesocarnivores, but also large carnivores at the top of the food chain, such as wolves. Therefore, rodent control is adding one further conservation threat to endangered large carnivores in anthropized landscapes of Europe, whose severity could increase over time and be far higher than previously thought. Large-scale monitoring schemes for ARs in European large carnivores should be devised as soon as possible.

High prevalence of anticoagulant rodenticide exposure in New England Fishers (Pekania pennanti).

Anticoagulant rodenticides (ARs) are increasingly recognized as a threat to non-target species including native wildlife. Fishers (Pekania pennanti) are generally considered deep forest inhabitants that are not expected to have high exposure to ARs. To evaluate the distribution and levels of ARs in fishers, we analyzed liver samples from fisher carcasses (N = 45) opportunistically trapped across Vermont and New Hampshire between 2018 and 2019. Liquid chromatography-mass spectrometry was used to detect and quantify 11 different ARs in the liver tissue of each fisher at the time of trapping. All but one sample analyzed were positive for exposure to ARs, and 84% were positive for more than one type of AR. The most prevalent ARs detected were diphacinone (96%) and brodifacoum (80%). No samples had detectable levels of coumachlor, coumafuryl, difenacoum, pindone, or warfarin. These results are mostly consistent with findings for fishers in California as well as with a variety of rodent specializing avifauna throughout the Northeast USA but, show a higher prevalence of exposure and a different distribution of AR types than other studies. These results help establish current baseline exposure to ARs in fishers in the Northeast USA and suggest that ARs could pose a threat to wild mesocarnivore species in this region.

Silent killers? The widespread exposure of predatory nocturnal birds to anticoagulant rodenticides.

Anticoagulant rodenticides (ARs) influence predator populations and threaten the stability of ecosystems. Understanding the prevalence and impact of rodenticides in predators is crucial to inform conservation planning and policy. We collected dead birds of four nocturnal predatory species across differing landscapes: forests, agricultural, urban. Liver samples were analysed for eight ARs: three First Generation ARs (FGARs) and five SGARs (Second Generation ARs). We investigated interspecific differences in liver concentrations and whether landscape composition influenced this. FGARs were rarely detected, except pindone at low concentrations in powerful owls Ninox strenua. SGARs, however, were detected in every species and 92 % of birds analysed. Concentrations of SGARs were at levels where potential toxicological or lethal impacts would have occurred in 33 % of powerful owls, 68 % of tawny frogmouths Podargus strigoides, 42 % of southern boobooks N. bookbook and 80 % of barn owls Tyto javanica. When multiple SGARs were detected, the likelihood of potentially lethal concentrations of rodenticides increased. There was no association between landscape composition and SGAR exposure, or the presence of multiple SGARs, suggesting rodenticide poisoning is ubiquitous across all landscapes sampled. This widespread human-driven contamination in wildlife is a major threat to wildlife health. Given the high prevalence and concentrations of SGARs in these birds across all landscape types, we support the formal consideration of SGARs as a threatening process. Furthermore, given species that do not primarily eat rodents (tawny frogmouths, powerful owls) have comparable liver rodenticide concentrations to rodent predators (southern boobook, eastern barn owl), it appears there is broader contamination of the food-web than anticipated. We provide evidence that SGARs have the potential to pose a threat to the survival of avian predator populations. Given the functional importance of predators in ecosystems, combined with the animal welfare impacts of these chemicals, we propose governments should regulate the use of SGARs.

Active metabolite of the neurotoxic rodenticide bromethalin along with anticoagulant rodenticides detected in birds of prey in the northeastern United States.

Little is known about the ecologic fate of the neurotoxic rodenticide bromethalin, which is currently registered for use in the United States, Canada, and other countries including Australia. There is minimal research on bromethalin's potential to cause secondary toxicosis in nontarget wildlife. The aim of this study was to evaluate adipose tissue in four species of birds of prey presented to a wildlife clinic in Massachusetts, USA, for desmethylbromethalin (DMB), the active metabolite of bromethalin. Birds were also screened for anticoagulant rodenticides (ARs) in liver tissue to present a more complete picture of rodenticide exposures in this geographic area and to evaluate the impact of current mitigation measures in place during the time of sampling, 2021-2022. A total of 44 hawks and owls were included; DMB was found in 29.5% of birds and ARs were present in 95.5%. All birds with DMB detections also had residues of ARs. Among birds positive for ARs, 81% had two or more compounds. To the authors' knowledge the data presented here represent the first published monitoring study to document bromethalin/DMB bioaccumulation in obligate carnivores. As DMB is a more potent neurotoxicant than its parent compound, these results are cause for concern and an indication that further monitoring and study of the potential risk of bromethalin to wildlife species is needed. These findings have global implications as increasing concern regarding exposure to and toxicosis from ARs in nontarget wildlife worldwide leads to a search for alternatives and effective mitigation approaches.

Validation and interlaboratory comparison of anticoagulant rodenticide analysis in animal livers using ultra-performance liquid chromatography-mass spectrometry.

Anticoagulant rodenticides (ARs) are used to control rodent populations. Poisoning of non-target species can occur by accidental consumption of commercial formulations used for rodent control. A robust method for determining ARs in animal tissues is important for animal postmortem diagnostic and forensic purposes. We evaluated an ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) method to quantify 8 ARs (brodifacoum, bromadiolone, chlorophacinone, coumachlor, dicoumarol, difethialone, diphacinone, warfarin) in a wide range of animal (bovine, canine, chicken, equine, porcine) liver samples, including incurred samples. We further evaluated UPLC-MS in 2 interlaboratory comparison (ILC) studies; one an ILC exercise (ICE), the other a proficiency test (PT). The limits of detection of UPLC-MS were 0.3-3.1 ng/g, and the limits of quantification were 0.8-9.4 ng/g. The recoveries obtained using UPLC-MS were 90-115%, and relative SDs were 1.2-13% for each of the 8 ARs for the 50, 500, and 2,000 ng/g spiked liver samples. The overall accuracy from the laboratories participating in the 2 ILC studies (4 and 11 laboratories for ICE and PT studies, respectively) were 86-118%, with relative repeatability SDs of 3.7-11%, relative reproducibility SDs of 7.8-31.2%, and Horwitz ratio values of 0.5-1.5. Via the ILC studies, we verified the accuracy of UPLC-MS for AR analysis in liver matrices and demonstrated that ILC can be utilized to evaluate performance characteristics of analytical methods.

Outcome of Rodenticide Poisoning and Its Associated Factors Among Adult Patients Admitted with Rodenticide Poisoning at the Emergency Unit of Debre Tabor Comprehensive Specialized Hospital, Debre Tabor, North Central Ethiopia.

Introduction: Rodenticides are pesticides used to eradicate rodents. It is a common reason for visits to the emergency department and hospitalization, and it is a major public health concern. Intentional or unintentional intoxication can result in severe consequences with a high fatality rate. In Ethiopia, studies on the outcome of rodenticide poisoning are scarce. The goal of this study was to assess the outcomes of rodenticide poisoning and its associated factors in adult patients admitted to the emergency unit of Debre Tabor Comprehensive Specialized Hospital in North Central Ethiopia. Methods: A retrospective record review institutional-based cross-sectional study design was used on 156 adult patients treated with rodenticide poisoning at Debre Tabor Comprehensive Specialized Hospital's emergency unit between May 1, 2017 and April 30, 2022. To collect data from patient medical documents and the Health Management Information System, an abstraction sheet was employed. The information was entered into EPI data version 4.6, then exported and analyzed using STATA version 14 software. To analyze the relationship between the dependent and independent variables, bivariable and multivariable regression were used. Results: A total of 156 participants were involved in the study. The majority of them 55.13% were in the age group of 19-37 years with the median age of 23 years. Three-fourth of the cases were suicidal poisoning. Overall, 49.35% patients presented to Debre Tabor Specialized Hospital had poor outcome. Having suicidal poisoning (AOR = 10.64; 95% CI: 2.43, 46.53), having tachycardia (AOR = 5.41; 95% CI: 1.54, 18.98), being referred from other health center (AOR = 5.78; 95% CI: 1.97, 16.95) were factors associated with poor outcome. Conclusion: Rodenticide poisoning had a poor overall outcome. Suicidal poisoning, tachycardia, and referral from other health facilities were all important predictors in poor rodenticide poisoning outcomes.

Clinical Use of Canine Thawed Refrigerated Plasma: A Historical Case Series.

Thawed plasma (TP) refers to defrosted fresh frozen plasma stored refrigerated. TP is used in human medicine for the rapid provision of coagulation factors and resuscitation of haemorrhagic shock, but its use in dogs is poorly described. The objectives of this historical case series were to describe the reasons for TP transfusion, treatment outcomes, and adverse events associated with canine TP transfusions in a veterinary teaching hospital. We hypothesised that TP would be used most commonly for the treatment of haemorrhage secondary to anticoagulant rodenticide intoxication and trauma. Blood bank plasma transfusion logs were searched to identify dogs that received at least one unit of TP between December 2015 and June 2021. Briefly, 166 dogs received a total of 262 units of TP. Anticoagulant rodenticide intoxication (37/166, 22.3%) was the most common reason for transfusion, followed by traumatic haemorrhage (23, 13.9%) and spontaneous haemoperitoneum (22, 13.2%). The majority of dogs received one unit of TP (111/166, 67.1%) and pRBCs were commonly simultaneously transfused with TP (65, 39.2%). Severe prolongations of prothrombin time and activated partial thromboplastin time were reduced following TP transfusions. Allergic reactions were the most common transfusion reaction (19/166, 11.4%). Most dogs survived to discharge (101/166, 60.8%).

Paper mulberry leaves as a potential sterilant: evidence from Microtus fortis-a laboratory study.

Introduction: The Yangtze vole (Microtus fortis) is a small herbivorous rodent that usually causes damage to crops and forests in China. Various measures were used to control their population including chemical rodenticides. However, rodenticides may cause secondary damage to the environment and the ecosystem. Therefore, the development of new rodent sterilants is urgent. Considering that some compounds of paper mulberry leaves have been verified that can inhibit the biosynthesis of sexual hormone, we aimed to explore the antifertility effect of paper mulberry leaves on M. fortis. Methods: In this study, voles were divided into three groups including a male group, a female group, and a breeding group, and paper mulberry leaves were added into basal fodder of voles maintained in laboratory, of which the proportion of leaf weight was 50%. In each group, voles were fed with mixed fodder as treatment (BP) and voles were fed with basal fodder as contrast (CK). Results and discussion: After feeding for more than 1 month, the results indicated that paper mulberry leaves attracted voles to feed, but inhibited their growth and reproduction. Since the second week, food intakes of BP have been significantly higher than CK (p< 0.05). However, weights of voles in male and female groups were 72.283 ± 7.394 g and 49.717 ± 2.278 g in the fifth week, and both were significantly reduced compared with their original weight (p< 0.05). Meanwhile, testicular volumes of male voles fed with BP were significantly smaller than CK (former: 318.000 ± 44.654 mm3, latter: 459.339 ± 108.755 mm3); the testosterone level, sperm number, and vitality of BP were obviously weaker than CK. Female uteruses and oophoron of BP grew slower, and the organ coefficients of uterus and oophoron fed BP were both significantly lower than CK (p< 0.05). The first reproduction of BP couple voles spent 45 days, while CK spent only 21 days. These results suggest that paper mulberry leaves could be the potential resource to produce sterilants to control rodent populations by delaying their sexual growth and reproduction. If it was practical, the apparent advantages of paper mulberry are that it is an abundant resource and the inhibitory effect could be effective in both male and female individuals. Our conclusion also supports the transformation of rodent management from lethal management to fertility control, which would be more ecologically friendly to agriculture and the ecosystem.

Análisis de un protocolo basado en la norma USEPA 1.213 para la evaluación regulatoria de la eficacia de las cebaderas en el control seguro de roedores pequeños / Analysis of a protocol based on the USEPA 1.213 standard for the regulatory evaluation of the efficacy of the bait station system in the safe control of small rodents

Varios rodenticidas modernos son formulados con compuestos anticoagulantes superwarfarínicos. Debido a su alta toxicidad en humanos, los cebos suelen ser formulados con otros ingredientes destinados a generar respuestas de rechazo en el caso de ingestión accidental o intento de suicidio; aun así, las unidades hospitalarias reportan anualmente numerosos casos de intoxicaciones con rodenticidas. Se han desarrollado cebaderas con el propósito de brindar al usuario alta eficacia y seguridad extendida. Dado que en muchos países existe experiencia limitada para la evaluación regulatoria de cebos combinados con cebaderas, en este trabajo se presenta un protocolo adaptado a partir de la guía USEPA- 1.213/1990, el cual se propone para verificar la aptitud de las cebaderas para controlar roedores en ambientes hogareños, ocupacionales y otros espacios urbanos. Se incluye una discusión de aspectos técnicos que se espera que sean de ayuda para los asesores de las agencias regulatorias intervinientes al interpretar los resultados en términos de eficacia y seguridad. El sistema cebadera-cebo examinado mostró alta letalidad en ratas adultas jóvenes. La inspección, carga y recarga de producto fresco se realizó en forma simple, rápida y segura; sólo excepcionalmente se observó dispersión del cebo fuera de la cebadera. Sin embargo, debe tenerse en cuenta que el sistema que solicita un registro ante la autoridad regulatoria debe ser adecuado a la especie que se busca controlar, considerando las diferencias de peso corporal entre ratas y ratones, entre machos y hembras, y entre animales jóvenes y adultos, lo cual determina la facilidad de ingreso al interior del dispositivo (cebadera) donde se coloca el cebo contenido en su embalaje unitario original. (AU)

Several modern rodenticides are formulated with anticoagulant superwarfarin compounds. Due to their high toxicity in humans, these baits are usually formulated with other ingredients intended to generate rejection responses in the case of accidental ingestion or suicide attempt. However, hospital units report numerous cases of poisoning with rodenticides every year. Box-like bait stations have been developed to provide the user with high efficacy and extended safety. Given that in many countries there is limited experience for the regulatory consideration of bait stations, this work presents a protocol adapted from the USEPA-1.213/1990 guideline, proposed to verify the aptitude of these devices to control wild rodents in home, work, and other urban spaces. The work includes a discussion of technical issues that are expected to be helpful to advisors of the regulatory agencies involved in interpreting the results in terms of efficacy and safety. The bait-station system examined showed high efficacy in young adult rats. The inspection, loading and reloading of fresh product were carried out in a simple, fast and safe way; bait dispersal outside the station was only rarely observed. However, it must be taken into account that the system that require a registration by the regulatory authority must be appropriate to the species sought to be controlled. This is important due to differences in body weight between rats and mice, between males and females, and between young and aged animals, which determines the ease of entry into the station where the bait contained in its original unitary packaging is placed. (AU)

Radiopaque rodenticide.

BACKGROUND: Rodenticide poisoning is common in developing countries. Patients may be unwilling or unable to provide a history on presentation. CASE HISTORY: A 34-year-old man was referred to the emergency department three hours after the intentional ingestion of five packs of a black powdered rodenticide containing zinc phosphide. Radiopaque material was detected in the stomach on an abdominal radiograph. CONCLUSION: Abdominal radiography may be a useful tool in identifying the ingestion of metal phosphides when a history is not obtainable.

Unique granulated leucocytes in peripheral blood in yellow phosphorous poisoning: An interesting tool for monitoring therapeutic response.

Yellow phosphorus is one of the most commonly used rodenticides in India for household pest control. It is available as pastes containing 2% to 5% of yellow phosphorus. Yellow phosphorous-containing rodenticides are easily available and account for one of the most common causes of suicidal poisoning in India. We describe a case of yellow phosphorus poisoning in a 17-years-old child who recovered from hepatic encephalopathy and showed unique peripheral smear findings in the form of spurious monocytosis and hypergranulosis of these granulocytes.

Acute oral toxicity of zinc phosphide: an assessment for wild house mice (Mus musculus).

Irregular plagues of house mice, Mus musculus, incur major economic impacts on agricultural production in Australia. The efficacy of zinc phosphide (ZnP), the only registered broadacre control agent for mice, is reported as increasingly variable. Have mice become less sensitive over time or are they taking a sub-lethal dose and developing aversion? In this laboratory study, the sensitivity of mice (wild caught; outbred laboratory strain) was assessed using oral gavage of a range of ZnP concentrations. The estimated LD50 values (72-79 mg ZnP/kg body weight) were similar for each mouse group but are significantly higher than previously reported. The willingness of mice to consume ZnP-coated grains was determined. ZnP-coated grains (50 g ZnP/kg grain) presented in the absence of alternative food were consumed and 94% of wild mice died. Mice provided with alternative food and ZnP-coated wheat grains (either 25 or 50 g ZnP/kg grain) consumed toxic and non-toxic grains, and mortality was lower (33-55%). If a sublethal amount of ZnP-coated grain was consumed, aversion occurred, mostly when alternative food was present. The sensitivity of wild house mice to ZnP in Australia is significantly lower than previously assumed. Under laboratory conditions, ZnP-coated grains coated with a new higher dose (50 g ZnP/kg grain) were readily consumed. Consumption of toxic grain occurred when alternative food was available but was decreased. Our unambiguous findings for house mice indicate a re-assessment of the ZnP loading for baits used for control of many rodents around the world may be warranted.