Anaemia and mortality in calves infested with the long-nosed sucking louse (Linognathus vituli)

Young calves which died on three dairy farms in England and Wales had generalised pallor and heavy infestations of the long-nosed sucking louse, Linognothus vituli. Surviving calves had packed-cell volumes, haemoglobin concentrations and red blood cell counts below the reference ranges, consistent with anaemia, and they were also heavily infested with lice. No other causes of anaemia were identified. It is proposed that heavy infestations with L. vituli should be considered when investigating the cause of anaemia in calves.     

Clinical efficacy of selamectin in the treatment of naturally acquired infection of sucking lice (Linognathus setosus) in dogs

A clinical study was performed in 21 dogs to evaluate the efficacy of selamectin for the treatment of naturally acquired infection of sucking lice (Linognathus setosus [L.setosus]) in dogs. Each dog was randomly assigned to one of two treatment groups. One group was treated with selamectin applied topically at a mean dosage of 7.9 mg/kg. The other group was treated with permethrin applied topically at a mean dosage of 85.7 mg/kg. At day 42 posttreatment, all animals remaining in the study (10 treated with selamectin and six with permethrin) were clear of lice. In both groups, the reduction in lice counts from pretreatment values to day 42 was statistically significant at P< or =0.0001. Selamectin applied topically appeared to be effective against L. setosus infection in dogs.     

The persistent efficacy of doramectin pour-on against biting and sucking louse infestations of cattle

A repeated-exposure challenge model was used to evaluate the pour-on formulation of doramectin in preventing the establishment of louse infestations in cattle. Twenty calves cleared of preexisting biting and sucking louse infestations were randomly and equally allocated to either a doramectin-treated or untreated control group, with five replicates per group. Doramectin pour-on was administered topically at a dose rate of 500 microg/kg body weight. Every 14 days, from a pool of seeder calves with infestations of at least 50 biting and 50 sucking lice each, 10 calves were selected and 1 was placed in each replicate pen. Every week during the 112-day study, 9 predilection sites on the doramectin-treated and untreated calves were examined to estimate the louse population density. A calf met the infestation criterion for a louse species when two or more live lice were counted on two or more body regions for two consecutive count days. Because only 4 of 10 untreated calves acquired Solenopotes capillatus infestations, the persistent efficacy of doramectin against S. capillatus was not evaluated. Bovicola bovis and Linognathus vituli infestations in the untreated calves developed shortly after exposure to infested seeder calves. The acquisition of B. bovis and L. vituli infestations in the doramectin-treated group was delayed for 77 days and 105 days, respectively.     

Persistent activity of moxidectin pour-on and injectable against sucking and biting louse infestations of cattle

To evaluate the persistent activity of pour-on and injectable moxidectin against natural challenge by sucking (predominantly Linognathus vituli) and chewing (Bovicola bovis) cattle lice, 96 mixed-breed calves that had been treated to remove all lice were blocked by body weight and randomly allocated to three treatments: untreated control, moxidectin at 500 microg/kg by topical application and moxidectin at 200 microg/kg by subcutaneous injection. Twelve pens were blocked into groups of four and randomly allocated to four challenge times: 14, 21, 28 and 35 days post-treatment. Treatment groups were assigned to challenge pens randomly. Two donor calves, with demonstrated infestations of both sucking and chewing lice, were introduced into each pen containing eight principal calves at the start of each challenge time. Donors remained in the challenge pen for 7 days. Principal calves were examined for lice, 7, 14, 21 and 28 days after donor removal using a standardized hair-parting technique. Moxidectin injectable prevented re-infestation with L. vituli for up to 42 days, but did not provide persistent activity against B. bovis longer than 35 days post-treatment. Moxidectin pour-on demonstrated persistent activity against both B. bovis and L. vituli for 42 days.     

The first record of sucking louse, Neohaematopinus callosciuri, infesting pallas squirrels in Japan

A species of sucking louse, Neohaematopinus callosciuri, was found for the first time in Japan. The species was found on an invasive species of squirrel, Pallas squirrel, Callosciurus erythraeus, in the Kamakura district, Kanagawa Prefecture, Japan. A total of 52 lice were obtained from 22 of 104 squirrels captured. The lice were about three times more prevalent in male squirrels than in females and were detected most frequently in the winter. As N. callosciuri has never been reported on wild animals in Japan, this species probably was introduced into Japan along with their host, Pallas squirrels.     

蜂胶提取物对山羊虱病的疗效试验

虱病是多种动物的多发性体外寄生虫病,轻者影响发育,繁殖率下降,皮毛失去经济价值,重者导致死亡,且多呈群体性发病,经济损失严重[1].长期以来主要采用有机磷,有机氯,有机氮等药物防治本病[2].但这些药物毒副作用强,残留量大,残留期长,环境污染严重,目前国内外已限制生产或逐渐淘汰. 蜂胶是养蜂业的副产品,是由蜜蜂上颚腺分泌物和采集来的天然有机物、无机物和蜂蜡组成,具有抗菌灭虫的生物学特性和良好的成膜作用[3,4].蜂胶对动物体表螨虫病有较好的疗效[5],而且安全无毒[6],是一种天然有效的生物灭虫新药.蜂胶对动物虱病是否具有治疗作用,为此我们进行了其对山羊虱病的疗效试验.     

Impact of the botanical insecticide Neem Azal on survival and reproduction of the biting louse Damalinia limbata on angora goats

Secondary metabolites present in the neem tree (Azadirachta indica A. Juss, Meliaceae), exhibit a wide range of biological activities in insects. However, few studies have been undertaken to assess the potential of neem products as insecticides for the control of ectoparasites of domestic animals. This study was undertaken to estimate the efficacy of Neem Azal, an azadirachtin-rich extract of neem seeds, in controlling Damalinia limbata (Phthiraptera) louse infestation of angora goats. The study was conducted on a fibre animal farm situated in Central Italy. Groups of 11-12 goats were treated with Neem Azal at an azadirachtin concentration of 650ppm or 125ppm, with Neguvon or were left untreated. Their louse burden was assessed fortnightly to monthly for 22 weeks. A reduction in louse densities of 76-96% was observed from week 2 to week 18 after treatment with the neem solution containing azadirachtin at a concentration of 650ppm. At the lower test concentration (125ppm) a reduction of 60-92% could be recorded from week 2 to week 14. Neem Azal was found to reduce the survival of both adult and nymph stages of D. limbata and to interfere with oviposition and oogenesis of female lice. A decrease in oviposition was observed in neem exposed female lice and the examination of their ovaries revealed morphological alterations in both vitellogenic and previtellogenic ovarioles at the follicular and germinal level. Since neem compounds target different life stages and physiological processes of D. limbata, the development of insecticide resistance by biting lice exposed to neem-based insecticides appears unlikely. For this reason and for its prolonged activity, which in principle allows angora goats to be protected for a large part of the mohair production cycle, neem-based insecticides may have a potential interest for mohair producing breeders.     

Seasonal occurrence and production effects of the biting louse Damalinia limbata on Angora goats and 2 treatment options

Adult biting lice Damalinia limbata (Gervais 1844) were most numerous on Angora goats in southwestern Free State Province from November to May with the smallest numbers present during August. Nymphs were most numerous from January to March with the smallest numbers present during July. The largest proportion of adult lice was present on the ventral surface of goats during winter, when population numbers were lowest, and the largest proportion of nymphs during summer, when population numbers were highest. Infestation did not affect the body weight of goats, but adversely affected both the quantity and quality of mohair produced. A single treatment with deltamethrin, applied as a pour-on along the mid-line of the backs of the goats, effectively controlled infestation and resulted in a significant increase in mohair production compared with untreated goats. Deltamethrin sprayed along the sides of the animals was equally effective in controlling infestation.     

中草药苦参碱水剂对羊体虱防治试验研究

寄生于羊体表的毛虱,属啮毛虱科(Trichodec tidae),主要有绵羊毛虱(D.ovis)和山羊毛虱(D.caprae).毛虱的传播方式主要是宿主的直接接触感染,其次通过混用的公共用具和褥草而间接传播.毛虱啮食宿主的毛和皮屑引起瘙痒,造成羊群不安,影响采食和休息.     

蜂胶提取物对离体山羊虱的药效试验研究

用0.10%、0.30%、0.50%、0.75%、1.00%和1.50%6个不同浓度的蜂胶提取液对离体山羊虱进行药效筛选试验,探讨了蜂胶提取物对离体山羊虱的灭虫效果.实验结果表明1.00%的蜂胶提取液对离体山羊虱的灭虫效果较好(P＜0.01),0.75%最好(P＜0.001).     

用蜂胶提取物治疗动物虱病的效果

本试验检测了动物虱虫病新型生物治疗药一蜂胶提取物的灭虱作用。不同动物在不同浓度下效果有所不同，猪和山羊用1．0％的鲜胶提取液，黄牛和水牛用1．5％的蜂胶提取物有100％的治疗效果，且具有无毒、无副作用、无污染等特性，克服了传统灭虱药的不足，是一种价廉、易得、操作方便的生物杀虫药。     

牦犊牛全哺乳效果观察

在海拔高度３４００～３８００ｍ的天然草地上进行１５０天的牦犊牛全哺乳（母牛不挤有）育肥试验，试验结果，在放牧条件下，全哺乳牦犊牛（ｎ＝１５）５月龄平均体重到７７．６１ｋｇ，平均增重６２．３４ｋｇ，较对照（母牛日挤奶一次）牦犊牛（３０．８ｋｇ）多增重３１．５４ｋｇ，增重率提高１９３．１７个百分点，头均纯收入增加５２．１６元左右，经济效益明显。     

不同品种山羊与雷州山羊杂交一代生长发育研究

以波尔山羊、奴比山羊、隆林山羊为父本，雷州山羊为母本所生的杂种后代（Bl、Nl、Ll)，在体形外貌上继承了其父本羊的特征，改善了雷州山羊的肉用体型和生长速度。杂种羊的出生重显著或极显著地高于同期出生的雷州山羊纯繁后代。在粗放的放牧饲养管理条件下，杂种公母羊2、4、6、8月龄的体尺均超过同龄的雷州山羊。杂种羊1至8月龄的体重和日增重均显著或极显著地高于同条件下饲养的同龄雷州山羊。如果改善和提高相应的饲养管理条件和营养水平，波尔羊的优良肉用遗传特性将会得到更充分的体现。