Efficacy and attractiveness of zinc phosphide bait in common voles (Microtus arvalis)

BACKGROUND: Minimising the concentration of active ingredient in rodenticide bait is desirable economically and for the protection of the agroecosystem. This study aimed to identify a zinc phosphide concentration that balances palatability and efficacy for common vole (Microtus arvalis Pall.) management and to compare the attractiveness of two bait carriers. RESULTS: Bait uptake of voles was reduced by 87–98% compared with plain bait when bait contained 0.4–3.2% zinc phosphide. There was an almost 50% decrease in the uptake of zinc phosphide when the zinc phosphide concentration of bait was doubled. Red dye used in commercially available bait decreased bait consumption by 10%. Daily consumption of zinc phosphide bait on days 2 to 5 was half the consumption on the first day of exposure. In bait choice tests, wheat kernels were preferred initially, but within 12 h similar amounts of wheat‐based pellets and wheat kernels were eaten. CONCLUSIONS: According to the results from the laboratory trial, a zinc phosphide concentration of 2.1% seemed to balance uptake/efficacy best and may be most appropriate for the management of common vole populations. This concentration is substantially lower than the concentration used in many registered products. A reduced concentration of active ingredient and the use of pellet bait instead of wheat which is highly attractive for birds may have advantages for agroecosystem health when applying zinc phosphide for rodent control. © Jens Jacob, Mechthild Budde and Angela Leukers, employees of the Federal Research Centre for Cultivated Plants, Germany. Printed with permission.     

Evaluation of a pelleted bait containing methyl anthranilate as a bird repellent

No-till agriculture involves the use of granular pesticide formulations, chemically treated seeds, and pelleted baits. Some of these may accidentally kill birds. We have tested whether methyl anthranilate (MA), a known bird repellent, would eliminate consumption of a pelleted bait. In two laboratory experiments and an outdoor aviary trial, cowbirds (Molothrus ater Bodd.) were presented with pellets containing pesticide and MA, pellets containing pesticide but no MA, and carrier pellets without pesticide or MA. Consumption of any formulation was low, but the addition of MA significantly decreased bait loss in the laboratory, and prevented the disappearance of bait in the outdoor trial.     

Mechanized Control of Muridae in Isolated Foci1

Rapid mortality resulted when kernel baits treated with zinc phosphide were used; baits were applied by different types of drills. Pre-planting treatment of the seed with heptachlor emulsion (40%) + TMTD had a highly repellent effect and considerably reduced rodent attack. Factors underlying the appearance of murid invasions are discussed.     

Ecological and Toxicological Bases of Directed Control of Arvicola terrestris (L.) and Microtus arvalis (Pallas) in Agricultural Crops 1

In order to protect crops during outbreaks of Arvicola terrestris (L.) or Microtus arvalis (Pallas), it is necessary to have formulations with acute action and high rodenticidal potential; rodenticides should be applied as baits corresponding to the hygrotrophic specialization of the species. When compared with zinc phosphide, Gliftor provides reliable control of voles in any season. The outlook of bactorodencide (bacterial preparation) applications is being determined with particular reference to their ecological effects.     

Toxicity of sodium fluoroacetate and zinc phosphide wheat grain baits to Microtus guentheri and Meriones tristrami

Whole wheat grains impregnated with 0.02, 0.05 and 0.2% sodium fluoroacetate, and 2% zinc phosphide, were offered to series of single caged individuals of Microtus guentheri and Meriones tristrami. In most cases the sodium fluoroacetate treated baits were well accepted by both species. The acceptance of the zinc phosphide-treated bait was partial in all the series tested. The approximate LD50 ranges of sodium fluoroacetate are between 0.24 and 0.43 mg kg⁻¹ for M. guentheri , and, perhaps, for the jirds too, and for zinc phosphide—between 32.6 and 58.8 mg kg⁻¹ for M. tristrami , and a similar value, more or less, for M. guentheri.     

An index technique to monitor broadcast calibration and bait pick up, plus rodent and avian sign under arid conditions

As part of product-performance and wildlife-hazards studies of 2% zinc phosphide (Zn3P2) steam-rolled-oat baits (11.2 kg ha-1) to reduce vole populations (Microtus spp) in alfalfa (Medicago sativa), we used randomly located, brushed-dirt plots (eight approximately 930-cm2 plots per 0.2-ha enclosure) to monitor bait-broadcast and -removal patterns, as well as to index vole and avian sign. Research was conducted in 18 x 0.2-ha enclosures containing 2.5-year-old stands of alfalfa; a 2-day pre-bait (placebo baits broadcast in all enclosures) period followed by a 14-day test-bait period (placebo and 2% Zn3P2 baits in nine enclosures each) characterized the bait exposures. Baits were broadcast manually by two certified pesticide applicators (CPAs) using Spyker Model-75 spreaders. Baits that fell onto plots were counted < 30 min later to assess the uniformity of bait distribution. The main statistical design was a 2 (placebo or Zn3P2 baits) x 3 (vole-only, vole-pheasant, vole-quail exposures) x 14 (days) factorial, with days considered repeated measurements. In the six vole-only enclosures, baits were removed from the brushed-dirt plots and replaced with four 0% or 2% Zn3P2 baits (one per 232.6-cm2 quadrant; 32 per enclosure); these 'placed' baits were then monitored daily for removal, while the surfaces of all plots were monitored daily for the presence:absence of animal/bird sign. Key results were: (a) 3.51 (+/- 2.66) and 3.39 (+/- 3.52) mean (+/- SD) baits were found on plots after pre-bait and test-bait broadcasts, respectively--less than the predicted 4.52 particles per 930-cm2 plot; (b) baits 'placed' on plots in placebo-baited enclosures were removed earlier than those in Zn3P2-baited enclosures--data in agreement with observed vole mortality; and (c) species x bait interactions occurred for both the vole- and pheasant-sign counts, but not quail-sign counts--data also indirectly confirming Zn3P2-induced mortality effects on voles and pheasants. This technique has utility for a variety of wildlife biology and chemical registration studies; although limited to arid conditions, the technique affords useful indices of broadcast calibration, bait pick-up, as well as target and non-target species mortality.     

Laboratory Evaluation of Zinc Phosphide as a Rodenticide against Bandicota bengalensis

Abstract

The toxicity and efficacy of the acute rodenticide zinc phosphide (Zn₃P₂) was evaluated in the laboratory against the lesser bandicoot rat (Bandicota bengalensis), from Rangoon, Burma. The acute LD50 and LD95 doses of orally-administered zinc phosphide for B. bengalensis were found to be 25.0 mg/kg and 113.0 mg/kg of body weight respectively. When caged bandicoots were given a choice between plain and poison baits, the optimum rodenticidal concentrations in the bait was found to be 2.5%. Symptoms of poisoning appear from 32 minutes to 3 hours after feeding starts, giving individual animals time to consume from 10 to over 27 LD50 doses of 25% zinc phosphide before feeding stops. Death occurred in a minimum of 4 to 5 hours following either oral dosing or free choice feeding. There appears to be aversion to the poison at higher concentrations in food baits. The relative merits of zinc phosphide and pyriminyl as rodenticides against the lesser bandicoot in Rangoon will have to be determined in a series of comparative field trials.     

Tenth international congress of plant protection,Brighton, November 1983

Abstract

Field trials were conducted to control rodent pests of wheat crop by improving bait acceptability through taste enhancers (additives). Egg shell, egg yolk, yeast, minced meat, sheep blood and chicken blood were mixed 2% by weight individually in a bait base of broken rice and wheat flour. Brodifacoum and bromadiolone bait with egg shell additive ranked first, and egg yolk second, in preference over other additive poison baits and poison bait without additive. Poison baiting yielded 93.3% and 86.7% reduction in rodent population with brodifacoum and bromadiolone (0.005% each), respectively. Three baitings, at tillering, flowering and maturity stage of the crop, gave 91.0% tiller damage reduction with brodifacoum and 86.0% with bromadiolone as compared to control (untreated). It is concluded that three poison baitings containing egg shell additive should be initiated at tillering stage followed by flowering and maturity of the wheat crop for increased yield.     

Rodenticide grain bait ingredient acceptance by Norway rats (Rattus norvegicus), California ground squirrels (Spermophilus beecheyi) and pocket gophers (Thomomys bottae)

Vertebrate pest control in California is often accomplished through the use of rodenticide grain baits. These grain baits are composed of steam-rolled oats (SRO), a toxicant, an indicator dye and an oil combination. A series of tests were performed to determine the effects of various dye and oil formulations on acceptance of grain bait by Norway rats [Rattus norvegicus (Berk)], California ground squirrels [Spermophilus beecheyi (Richardson)] and pocket gophers (Thomomys bottae Eyd & Gerv). Seven different dyes, four oil formulations and clean (untreated) oats were tested for acceptance. The addition of the selected oils and dyes to grain resulted in no significant differences in consumption. This indicates that there is a wide variety of dyes that could be used in the formulation of rodenticides. These alternatives could aid in proper pesticide use, the deterrence of bait consumption by birds and possibly in ingredient adhesion to the finished bait.     

Rejection of dyed field rodent baits by Feral Pigeons and Chukar Partridges

Whole wheat grain bait, treated with sodium fluoroacetate, is used to control field rodents in Israel. However, this bait constitutes a potential primary non-target hazard to seed-eating birds. In the present study black-, red-, green- and yellow-dyed whole wheat and sorghum grains, as well as undyed ones, were offered to feral pigeons,Columba livia, and to chukar partridges,Alectoris chukar, in the laboratory during 4 days. Grains were offered either piled on trays, or scattered. Consumption levels varied significantly (P<0.05) among varieties. The pigeons preferred undyed grain; black and yellow grains were consumed the least. The partridges preferred the undyed and black grains to all the other colored grains. When no undyed alternative was offered, the pigeons preferred red and green, and the partridges — black wheat. The pigeons preferred wheat whole grain, and the partridges — sorghum whole grain. When the pigeons received sorghum, a disliked grain, no significant difference (P>0.05) was observed in the consumption of the differently dyed grains.     

Bait additives as a means of improving acceptance by rodents1

There is a general desire by those formulating rodent baits to improve them to achieve better rodent control. Various bait additives are currently in use while others have been evaluated without significant benefit. Some food or taste preferences are innate while other specific food preferences of rodents are learned during early experiences in life. Sugar (sweet items) and vegetable oils and animal fats are the most universally effective additives for cereal baits to improve acceptance and palatability for the three major species of commensal rodents. Salt, monosodium glutamate, and a wide array of natural, semi-natural, and synthetic flavors/aromas as bait enhancers have been explored as gustatory (taste) and olfactory (odor) additives. Their influence on rodents seeking out the bait and on bait acceptance are varied and inconsistent. Flavor additives to baits have often decreased rather than increased consumption.     

Factors affecting red-winged blackbird response to methiocarb,an avian repellent

Two physiological responses (heart rate and respiration rate) and a behavioral response (keypecking rate) were measured to determine whether or not bait from and/or gastrointestinal content would influence the efficacy of an avian repellent on red-winged blackbirds. Methiocarb was administered under four conditions (i.e., cracked corn or pellet baits and food deprivation or nondeprivation). Results show that both physiological and behavioral responses to methiocarb are much more pronounced when it is administered in pellet form to food-deprived birds. These findings help explain some inconsistencies in results of field evaluations of methiocarb and illustrate the significance of formulation and the timing of treatment application as important factors in development of bird damage control agents and techniques.     

Production of UV-light-detectable faeces from house mice (Mus musculus domesticus) after consumption of encapsulated fluorescent pigment in monitoring bait

BACKGROUND: The authors investigated whether fluorescent pigment in thermoset melamine microcapsules incorporated into monitoring baits would be excreted in the faeces of wild house mice in a quantity and intensity that would be detectable by a human observer. RESULTS: Experimental mice produced 24–116 UV‐visible faecal pellets per 24 h; the mean dry weight was 582 mg. The number and weight of the faeces was independent of mouse sex and weight. The defecation of UV‐visible faeces began at 2–3 h, peaked at 5–8 h and was complete at 17 h after bait ingestion. The detectability of the highly fluorescent faecal pellets using a small UV flashlight approached 100%, and no false positives were recorded. CONCLUSION: The tested formulation is of significant value for rodent pest monitoring because faeces that are highly visible by UV light are produced for 15 h by mice after ingestion, and their detection is easy and unambiguous. Copyright © 2011 Society of Chemical Industry     

Behavioral responses of red-winged blackbirds (Agelaius phoeniceus) to viewing a conspecific distressed by 4-Aminopyridine

4-Aminopyridine (4-AP) is the only pesticide that can be legally used in the US to reduce bird damage in ripening grain fields. Birds that consume grain baits treated with 4-AP (‘Avitrol’ FC-99®) exhibit erratic behavior and emit vocalizations that presumably scare away the rest of the flock. Yet the behavior of 4-A Pintoxicated birds has not been documented, and we do not know how other birds react when observing these intoxicated birds or what these observers learn from their experience. Hence, we examined the behavior of 15 4-A Pintoxicated red-winged blackbirds (Agelaius phoeniceus (L.)) and found that initial signs of intoxication occurred 12.5 min after consumption of the bait, with death following 16.3 min later. During this 16-min intoxication period, birds gradually lost muscular control, making their movements and vocalizations weaker until hardly perceptible. Other captive red-winged blackbirds (‘observers’) gave more alarm calls while witnessing a 4-A P-intoxicated bird in one room of their cage (treatment period) than they did during the pre-treatment period. Immediately after the intoxicated bird died and was removed from the room, the observers' behaviour returned to pre-treatment levels. Broadcasting calls of an intoxicated bird or the placement of an untreated bird in one of the rooms had little effect on the observers' behavior. In another experiment, the placement of a 4-A Pintoxicated or untreated red-winged blackbird or the broadcast of calls of an intoxicated bird at a feed station did not affect the number of free-ranging conspecifics feeding, within sight of, or vocalizing at, these feeder stations. These results suggest that red-winged blackbirds learn little from witnessing a distressed conspecific.     

小家鼠选择性摄食试验

在毒饵杀灭家栖鼠类中,诱饵和诱饵增味剂常常受到重视,但由于地理、地产农作物的不同及人类生活习惯差异,造成鼠类对各种食物的选择。就同人类具有明显的地方口味一样,鼠类可能也有地方口味。为了解乌鲁木齐市的主要鼠种——小家鼠的地方口味,我们做了下述实验。 1.材料和方法 1.1.试验用鼠:捕自乌鲁木齐市某商场和某学院的小家鼠,即以溴氰菊酯除去体外寄生     

The Problem of Protecting Crops Against Harmful Birds in Poland

From the point of view of Polish agriculture, the rook (Corpus frugilegus L.) causes the most damage. Jackdaws (C. monedula L.) usually forage together with rooks and are equally abundant as a breeding species in the southern and central regions of Poland. Fields under spring oats, barley, wheat, maize, peas and winter wheat are the main feeding grounds of rooks and jackdaws. Unlike the corvine birds, starlings (Sturnus vulgaris L.), in Poland, only cause damage to cherry orchards, although in certain areas they also attack strawberries and currants. The house sparrows (Passer domesticus L.) cause considerable damage to ripening crops of wheat, barley, and sunflowers. Domestic pigeons cause considerable damage to crops of peas, wheat and maize grown within a 50 km radius of a town.     

新疆干旱半干旱农田应用0.2%莪术醇饵剂防治害鼠的效果

为了解0.2%莪术醇饵剂在新疆干旱半干旱农田应用的可行性,2022年4月至7月, 在新疆博州温泉县进行了该药防治害鼠试验。施药在3个试验点(即3个重复)进行, 在害鼠繁殖高峰期前施药, 投放药饵后30、60 d和90 d调查防控效果。结果显示:3个试验区域的结果趋势相似, 校正灭效基本维持在50%以上。与空白对照区相比, 优势鼠种灰仓鼠与根田鼠试验投饵区的雌鼠怀孕率明显下降, 小家鼠、灰仓鼠平均胎仔数明显降低, 小家鼠、灰仓鼠和根田鼠施药区域的鼠类个体的亚成体比例与对照区域明显下降, 说明该药剂对当地害鼠的繁殖具有明显的控制作用, 可达到控制害鼠数量的目的, 适口性也较好, 可以在当地推广应用。     

Aversion of the feral pigeon and the house sparrow to pellets and sprouts treated with commercial formulations of methyl anthranilate

Two methyl anthranilate formulations, ReJex‐iT® TP‐40 and AG‐36, were tested as bird‐repelling agents for animal feed and vegetable sprouts, respectively. Feral pigeons (Columba livia) and house sparrows (Passer domesticus) are important pests of animal husbandry and field crops in Israel. In each 4‐day experiment, four birds were held together in an aviary, and were offered four trays or dishes with animal feed or cauliflower sprouts in four corners of the cage. The trays and dishes were transposed daily in a Latin square sequence. Pigeons consumed significantly more untreated feed than treated feed. When no alternative untreated food was offered, there was no significant repellency. Treatment of animal feed with TP‐40 to give 2.0 ml methyl anthranilate kg^?1 or less had no repellent effect on sparrows. Concentrations of 4.0 ml kg^?1 or more repelled the sparrows significantly. When no untreated feed was presented, pigeons and sparrows preferred the lowest concentration of methyl anthranilate presented. When AG‐36 was tested on vegetable sprouts, the sparrows tended significantly to avoid the highest concentration used—14.5 ml methyl anthranilate litre^?1 spray. The inter‐specific differences between the birds indicate that the efficacy of methyl anthranilate formulations as a repellent has to be specified for every species. This study did not determine (1) the possibility of developing habituation, (2) the behaviour of birds under natural conditions in the field, or (3) the influence of the feeding behaviour of a sympatric bird species on the repellency of methyl anthranilate to other species. © 2001 Society of Chemical Industry     

华北平原旱作区农田害鼠化学防治技术的优化筛选研究

作者研究了不同投饵方式,不同灭鼠季节和不同杀鼠剂的农田灭鼠效果,并研究了溴代毒鼠磷和磷化锌不同浓度与不同投饵量对农田害鼠的灭杀率,筛选出了农田灭鼠优化技术:封锁带式投饵,0.5%溴代毒鼠磷小麦毒饵每堆投饵2克,全年中灭鼠适期为3—4月份。这套优化灭鼠技术较从前采用的灭鼠技术提高了灭效,而且大幅度降低了灭鼠成本。     

华北平原旱作区农田害鼠化学防治技术的优化筛选研究

作者研究了不同投饵方式,不同灭鼠季节和不同杀鼠剂的农田灭鼠效果,并研究了溴代毒鼠磷和磷化锌不同浓度与不同投饵量对农田害鼠的灭杀率,筛选出了农田灭鼠优化技术:封锁带式投饵,0.5%溴代毒鼠磷小麦毒饵每堆投饵2克,全年中灭鼠适期为3-4月份。这套优化灭鼠技术较从前采用的灭鼠技术提高了灭效,而且大幅度降低了灭鼠成本。