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1.
An investigation of the landing and engorging sites of midges on a bait horse was made in Ireland as part of a project examining the aetiology of sweet itch. Ten species were recovered, seven of which engorged. Culicoides obsoletus and C dewulfi were the most commonly represented, accounting for 89.9 per cent of midges landing and 90.5 per cent of midges engorging. Only 4.69 per cent of midges attracted to the bait were C pulicaris. Overall, the preferential landing sites for midges were along the mane and lower leg regions. Few culicoides were attracted to the head, front and underside of the animal. Two species, C punctatus and C nubeculosus, fed exclusively at the predilection sites of sweet itch but in very small numbers. C pulicaris fed predominantly at these sites also and represented 5.08 per cent of the engorging catch. Of 10,178 midges attracted to the bait, 4097 (40.3 per cent) engorged; the majority of the species taking full blood meals fed on the mane and lower legs. Midges biting in other areas tended to have smaller meals. Areas along the dorsal midline of the body are predilection sites for sweet itch lesions and are preferential engorging sites also. However, considerable engorgement occurred on the lower legs where sweet itch lesions do not occur.  相似文献   

2.
秦皇岛地区十个鸡场鸡球虫种类的初步调查   总被引:6,自引:1,他引:5  
通过对秦皇岛地区10个养鸡场鸡球虫种类的调查,发现8个养鸡场为球虫阳性,共检出6种球虫,分别是哈氏美耳球虫(34%)、柔嫩艾美球虫(26%)、早熟艾美耳球虫(12%)、和缓艾美耳球虫(12%)、堆形艾美耳球虫(11%)和毒害艾美耳球虫(5%)。  相似文献   

3.
4.
本文针对发生腹泻疫情的某猪场开展了实验室检测和流行病学调查,实验室检测表明该疫情的病原为猪流行性腹泻病毒。流行病学调查显示,此次腹泻疫情于2013年11月份开始暴发,2014年3月份结束,发病猪的种类具有明显的次序,育肥猪首先发生,其次是母猪,新生仔猪最后发病;发病率和死亡率与猪的种类、日龄密切相关,育肥猪和母猪发病后仅出现腹泻症状而不死亡,仔猪发病后腹泻症状明显而且死亡率随着年龄的增长急剧下降,3日龄以下仔猪死亡率可达100%,1周龄仔猪死亡率降至72.73%,12日龄仔猪死亡率仅有10%。对猪场风险因素分析表明,饲料车辆直接进入猪场、卖猪车辆与饲养人员接触、粪便通道没有封闭、饲养人员流动等是影响此次腹泻疫情的高风险因素,通过降低高风险因素很好地控制了疫病。  相似文献   

5.
A lightweight, collapsible, tent-type, trap of 1 m2 floor-area was developed for the collection of emerging Culicoides from a wide range of habitats. It is cheap; easy to build, transport and erect; withstands adverse climatic conditions well; affects the covered habitat only slightly; and needs little attention. Insects are trapped into 0.5% aqueous "Savlon" solution in a removable, modified, 2 litre plastic bottle. In this, the catch remains fresh for up to 2 weeks and is still suitable for identification and mounting for taxonomic purposes. Emergence numbers of 100 or more Culicoides/m2/day are quite common with this trap.  相似文献   

6.
Culicoides spp. act as vectors for a number of viral diseases of animals including bluetongue in sheep. The aims of this study were to determine: (1) which Culicoides spp. are associated with sheep in The Netherlands; (2) the time of the day when they are most active; and (3) the effect of treatment of animals with a permethrin insecticide. Two pairs of sheep were each housed within mosquito tents of either one or two layers of netting and all trapped Culicoides spp. were identified microscopically. For the permethrin insecticide study, one of two pairs of sheep was treated with 3.6% permethrin and all animals were housed in tents of similar design. Of the 6210 midges captured, 54.1% were identified as C. chiopterus and 42.7% as C. obsoletus. C. imicola was not identified. The average insect feeding rate was 35-40% and midge activity was greatest around sunset. Permethrin treatment reduced the number of midges captured by 50% and also resulted in a decrease in the percentage of midges that had fed. The findings provide useful information on the behaviour and distribution of Culicoides spp. that will facilitate the development of appropriate control strategies to minimise the risk of insect-vector borne virus diseases such as bluetongue.  相似文献   

7.
Free-living stages of ticks on a commercial game farm in the Thabazimbi District, Limpopo Province, South Africa, were collected by drag-sampling with flannel strips during the period September 2003 to August 2004. A total of 5 tick species was collected from 4 sites. Boophilus decoloratus was the most abundant species, followed by Amblyomma hebraeum. Seasonal abundance of the ticks was quantified and an optimum time to implement control measures against the ticks is proposed.  相似文献   

8.
While wing form is known to differ between males and females of the genus Culicoides, detailed studies of sexual dimorphism are lacking. In this study, we analyze sex-specific differences in the wing form of 5 species of the subgenus Avaritia, using geometric morphometrics and comparative phylogenetic methods. Our results confirm the existence of marked sexual dimorphism in the wing form of the studied species and reveal for the first time that while there is a shared general pattern of sexual shape dimorphism within the subgenus, sexual size dimorphism, and particular features of sexual shape dimorphism differ among species. Sexual shape dimorphism was found to be poorly associated to size and the evolutionary history of the species. The tight association of sexual shape dimorphism with aspect ratio suggests that the shape of the wing is optimized for the type of flight of each sex, that is, dispersal flight in females versus aerobatic flight in males. Moreover, the fact that interspecific shape differences are greater and more strongly associated to aspect ratio in males than in females might be indicating that in males the selective pressures affecting flight performance characteristics are more heterogeneous and/or stronger than in females among the studied species.  相似文献   

9.
陕西杨凌某种牛场奶牛球虫种类的调查   总被引:1,自引:1,他引:1  
对陕西杨凌某种牛场荷斯坦奶牛球虫感染情况进行了调查,发现该场犊牛球虫平均阳性率为45.83%(22/48),每克粪便中所含的卵囊数最大值为1 100。共鉴定出8种艾美耳属的球虫,其中亚球形艾美耳球虫(Eim eria subsperica)检出率为31.57%,邱氏艾美耳球虫(E.zuernii)检出率为10.42%,椭圆艾美耳球虫(E.ellips)检出率为8.33%,阿拉巴马艾美耳球虫(E.alabam ensis)检出率为10.42%,牛艾美耳球虫(E.bovis)检出率为22.92%,加拿大艾美耳球虫(E.canadensis)检出率为6.38%,柱状艾美耳球虫(E.cylindrica)检出率为10.42%,奥博艾美耳球虫(E.auburnensis)检出率为4.17%,优势种为亚球形艾美耳球虫和牛艾美耳球虫。  相似文献   

10.
Brucellosis is an endemic anthropozoonotic disease in most Middle East countries including Iraq. It causes considerable loss of economy and energy, particularly in the rural areas. Since 1966 when the prevalence of brucella agglutinin from slaughtered sheep and goat was reported in Baghdad, several trials have been conducted including serological studies of brucellosis in the northern provinces of Iraq (Nainava, Duhok, Erbil, Kirkuk and Sulaimani). Humans, sheep, goats, cattle and buffalo have been involved. The studies also included isolation and identification of Brucella species, including B. abortus, B. melitensis and B. ovis. Local veterinary authorities, international organizations, universities and some NGOs have been involved. Moreover, limited efforts have been reported concerning the control and eradication of the disease among goats and sheep in some restricted areas. A limited vaccination program for newborn lambs and kids also has been conducted by the FAO, which was involved in the veterinary emergency plan for brucellosis in 2000. Northern provinces share an extensive border with Iran, Turkey and Syria, in addition to the direct and intimate contacts with other provinces of Iraq, which share borders with Jordan, Saudi Arabia and Kuwait. Hence any strategic planning for the control or eradication of this devastating anthropozoonotic disease in the country should be implemented regionally and not locally.  相似文献   

11.
Six hundred and twenty culicoides of five species were collected from a bait horse at Kannot, Israel, between April and September 1986. Seventy-two per cent of the midges were collected from the belly and 27 per cent from the dorsal aspect of the body, ie, the sweet itch summer seasonal recurrent dermatitis (SSRD) zone. Midges were active mainly from half an hour prior to half an hour after sunset. Only Culicoides puncticollis, C imicola and C schultzei group were collected in considerable numbers. While C imicola was present continuously throughout the season, the appearance of the two other species was intermittent. Ninety-five per cent of C schultzei group and approximately 100 per cent of the C puncticollis prefer to land on and most probably bite the belly. Culicoides imicola showed a clear preference for the dorsal ridge which overlaps the (SSRD) itch zone, and 70 per cent of the midges were collected there, while 28 per cent were collected from the belly. A considerably high proportion of the midges of this species were parous, ie, part of the population lived long enough to bite more than once. Skin temperature measurements showed the belly to be the warmest part of the body. Wind speeds of two to three knots reduced the number of midges collected. The findings of this study, together with a previous one (Braverman et al 1983), incriminate C imicola as the likely principal agent of SSRD in Israel.  相似文献   

12.
13.
Mastitis caused by Prototheca spp or Nocardia spp is considered to be difficult to treat. Both microorganisms are contaminants commonly found in soil. The occurrence of mastitis caused by these agents was studied in a particular dairy farm. In this herd, the animals were kept at pasture overnight and during daytime were brought to a pen where they were fed. This pen accumulated mud and faeces, particularly in the rainy season. During milking, pre-dipping of the teats was performed with an iodide solution, but they were not washed, so a layer of soil and faeces remained which may have contaminated the milking equipment. The herd comprised 91 lactating animals and 47 dry cows. For microbiological examination, 107 milk samples were collected from lactating cows and 186 samples of mammary secretions from the dry cows. Prototheca spp were isolated from 14.55% of the milk samples and Nocardia spp from 4.55%. Prototheca spp were isolated from 8.06% of the secretion samples from dry cows and Nocardia spp were isolated from 2.15% samples. The high occurrence of mastitis due to these environmental agents reflects the problem of keeping animals in muddy pastures and pens, and the defective pre-milking hygiene for the teats.  相似文献   

14.
石河子紫泥泉种羊场绵羊球虫种类调查   总被引:4,自引:1,他引:4  
对石河子紫泥泉种羊场的绵羊球虫种类及感染现状进行了调查,共发现艾美耳球虫11种,分别是小型艾美耳球虫(E.parva)、似绵羊美耳球虫(E.ovinodalis)、巴库艾美耳球虫(E.bakuensis)、颗粒艾美耳球虫(E.granulosa)、阿撒他艾美耳球虫(E.ahsata)、槌型艾美耳球虫(E.intricata)、韦不里吉艾美耳球虫(E.weybridgensis),对各虫种卵囊进行了测量和形态描述。  相似文献   

15.
Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured. A total of 16,538 biting midges were collected from 2010 to 2011, including seven species of Culicoides, four of which represented 98.42% of the collected specimens. These four species were Culicodes (C.) punctatus (n = 14,413), C. arakawae (n = 1,120), C. oxystoma (n = 427), and C. maculatus (n = 318). C. punctatus was the predominant species (87.15%).  相似文献   

16.
Resistance to thiabendazole (TBZ), fenbendazole (FBZ) and levamisole (LVM) in naturally acquired gastrointestinal nematode parasites in sheep was investigated on a farm where anthelmintic resistance was suspected. This was measured by both the in vitro egg hatch assay, and reductions in faecal egg and worm counts in treated animals. In the egg hatch assay, nematode eggs were incubated in various concentrations of either TBZ or LVM. The level of resistance was expressed as the drug concentration inhibiting 50% of the eggs from hatching (LC50). The nematode population had LC50 values of 0.26 microgram ml-1 TBZ and 3.12 micrograms ml-1 LVM. In the faecal egg and worm count reduction test, naturally infected sheep were treated with either TBZ (88 mg kg-1), FBZ (10 mg kg-1) or LVM (15 mg kg-1). Faecal egg and total worm counts from these sheep were then compared with counts from untreated sheep. TBZ, FBZ and LVM failed to reduce the faecal egg counts and total worm counts by more than 90%. Based on the identification of larvae from faecal cultures, the most predominant nematode species in the resistant population were Haemonchus (62%) and Trichostrongylus (28%). TBZ reduced faecal egg counts for both species by less than 90%. FBZ and LVM also reduced Haemonchus spp. eggs by less than 90%. Other nematode species numbers did not satisfy criteria for the determination of efficacy.  相似文献   

17.
Masting is an evolutionary strategy used by plants to promote seed survival and/or seed dispersal under animal predation, but its effects on seedling establishment in field condition are rarely tested by long-term experiments incorporating combined effects of seed and animal abundance. Here, we tracked seed production, rodent-mediated seed dispersal, and seedling establishment in Armeniaca sibirica from 2005 to 2014 in a warm-temperate forest in northern China, and examined the effects of seed abundance and per capita seed availability on seed fate and seedling recruitment rate. Our results showed that seed abundance or per capita seed availability generally benefited the seedling recruitment of A. sibirica through increasing dispersal intensity, supporting predator dispersal hypothesis. However, seedling recruitment showed satiated or even dome-shaped association with per capita seed availability, suggesting the benefit to trees would be decreased when seed abundance were too high as compared to rodent abundance (a satiated effect). Our results suggest that the predator dispersal and satiation effects of masting on seedling recruitment can operate together in one system and conditionally change with seed and animal abundance.  相似文献   

18.
Tropical Animal Health and Production - African animal trypanosomiasis is a major cause of mortality and economic losses for the livestock industry in Nigeria. Chemotherapy has been the most...  相似文献   

19.
A one-year-old domestic long-haired cat was referred to the New York State College of Veterinary Medicine because of acute onset of paraparesis and hyperesthesia associated with trauma. Myelography and cerebrospinal fluid analysis revealed severe hydromyelia and myelitis, respectively. The definitive diagnosis of feline infectious peritonitis was made by histological examination at necropsy. Lesions were confined exclusively to the brain and spinal cord. Partial occlusion of the third and fourth ventricles with pyogranulomatous debris caused hydrocephalus and subsequent hydromyelia. The hydromyelia may have been the primary means of compensation for the hydrocephalus, thus masking subclinical disease.  相似文献   

20.
A survey was performed to characterize the dairy production, educational experiences, decision making practices, and income and expenses of dairy farms and to determine any differences of these practices among two dairy farm populations. Farm groups were identified as farms from the Muaklek dairy cooperative (Muaklek farms) and farms from other dairy cooperatives (Non-Muaklek farms). In April, 2006 questionnaires were distributed to 500 dairy farms located in Lopburi, Nakhon Ratchisima, and Saraburi provinces. A total of 85 farms completed and returned questionnaires. Means and frequencies were calculated for questions across categories and Chi-square tests were performed to determine differences among Muaklek and Non-Muaklek farms. Results showed that most farms from both groups had a primary or high school educational level, used a combination confinement and pasture production system, gave a mineral supplement, raised their own replacement females, milked approximately 16 cows/day, used crossbred Holstein cows (75% Holstein or more), and mated purebred Holstein sires to their cows. More Non-Muaklek farms (P < 0.05; 80%) used a combination of genetic and phenotypic information when selecting sires than Muaklek farms (54%). Monthly profit per lactating cow, were 1,641 and 1,029 baht for Muaklek and Non-Muaklek farms, respectively. Overall, information from the study should be useful for dairy cooperatives and other dairy organizations when training farmers in the future and furthering dairy production research in Thailand.  相似文献   

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