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1.
Warbles induced by the rodent bot fly larvae, Cuterebra fontinella, developed over a period of 3.5-4 weeks in the deer mouse Peromyscus maniculatus. Warble location, structure and dynamics were examined. Clustering of warbles occurred primarily within the inguinal region of the deer mouse with a significant number favoring the area between the anus and genital organ. No differences in warble production were found in hosts of either sex. On two occasions, a warble was encountered forming directly in the genitals. Warble structure consisted of a pore, cavity and capsule, all of which changed in shape and size as the larvae grew. A new pore was formed during the first larval molt and was commonly bordered by a yellowish precipitate. A bi-layered warble capsule surrounded the cavity as a thin layer and a thick diffuse outer layer. The growing warble expanded into the subcutaneous tissue of the inguinal area and stretched the hide caudally. Subcutaneous tissue surrounding developing warbles became relegated to small areas, leaving only a thin muscle to separate the warble from the peritoneum. Widening of the pore at the time of larval emergence is described. Linear relationships are given describing warble growth and pore enlargement as a factor of time. The location of warbles and the morphology of the pore are discussed in relationship to larval protection. Damage to the host due to warble formation is also addressed.  相似文献   

2.
The objective of the present study was to observe the seasonal pattern of the life cycle and the warble stage in bovines of Dera Ghazi Khan and Rajan Pur Districts of Southern‐Punjab, Pakistan. The study was conducted from July 2004 to June 2005. The association was studied between various climatic changes and the fly life cycle. The larvae of warble flies were extracted from the backs of naturally infested animals and identified. The adult fly laid eggs in June, and hatched larvae penetrated the skin and followed intensive internal migration to diaphragm, esophageal wall and subcutaneous connective tissue in the month of July. At the start of August they reached the subcutaneous tissue and emergence began. In both species, the maximum warble emergence was found in mid‐December and the lowest in mid‐March and mid‐August. It was concluded that preventive treatment should be adopted before the month of July to avoid carcass depreciation and decreased leather quality.  相似文献   

3.
A massive infestation with warble fly larvae was observed in a mare in Lower Saxony, Germany. From a herd of 20 horses, only a single mare accidently escaped the routine treatment with macrocyclic lactone in autumn and showed the myiasis infestation next year in January. Eighteen subcutaneous nodules were found on the back (n = 2), ribs (n = 3), flank (n = 5) and croup (n = 8). Deer, the specific hosts of the warble fly Hypoderma diana, was abundant on this farm and some other risk factors for the hypodermiosis are discussed herein. This is the first report of myiasis caused by H. diana in horses in Germany. This massive warble fly infestation in a horse in Germany reported here is important to alert equine health professionals concerning the prevention of this disease in the routine parasite control programme.  相似文献   

4.
Cattle hypodermosis (warble fly infestation) is a notorious veterinary problem throughout the world. Larvae of Hypoderma species cause a subcutaneous myiasis of domesticated and wild ruminants. This disease is caused by, Hypoderma bovis, Hypoderma lineatum in cattle whereas, Hypoderma diana, Hypoderma actaeon, and Hypoderma tarandi, affect roe deer, red deer, and reindeer, respectively. Adults of the cattle grub are commonly known as heel flies, warble flies, bomb flies or gad flies. The biology of hypodermosis is complex because it passes through ecto- as well as endoparasitic stages in the life cycle. The parasitic stage of hypodermosis lasts about 1 year in domesticated as well as in the wild animals, while in the adult stage, a free-living fly lasts only for few days. The diagnosis of hypodermosis is of prime importance for planning treatment and the eradication program. Generally, there are two methods that are routinely used for diagnosis of hypodermosis, i.e., the direct clinical examination and immuno diagnosis by the use of pooled serum and/or milk sample. For the control of hypodermosis, different preparations are available and their use in most of the countries is limited to an individual level but never cover the whole cattle population of a country. Re-infestation in the herd occurs due to the untreated animals that remain the reservoir of the disease. The disease causes huge economic losses in animal production due to the effect of this disease on meat, milk, and the leather industry. It can also affect the general health status as well as the immune system of the body of the diseased animals. As regards the control measures of the disease, different methods have been efficiently practiced and consequently this disease is controlled at national level in many European countries.  相似文献   

5.
The deer ked (Lipoptena cervi) is a haematophagous parasitic fly of cervids that spread to Finland in the early 1960's. Presently its northern distribution limit lies at approximately 65°N and it is gradually spreading northwards. In Finland the principal host species has been the moose (Alces alces), but the deer ked is about to establish contact with another potential host, the semi-domesticated reindeer (Rangifer tarandus tarandus) causing possible threats to reindeer health and management. The aim of this study was to investigate if the deer ked would have an influence on the welfare of the reindeer. Eighteen adult reindeer were divided into three experimental groups: the control group and two infected groups with 300 deer keds per reindeer introduced in August-September. One of the infected groups was treated with subcutaneous ivermectin in November. To gather comprehensive data on potential health hazards caused by the deer ked a wide array of physiological variables was measured during and at the end of the experiment in December. The keds caused no clear changes in the complete blood count, plasma clinical chemistry, amino acids, endocrinology, energy stores, enzyme activities or tissue fatty acid profiles of the host. The haematological, clinical chemical and endocrinological values displayed changes that could be related to the seasonal physiological adaptations of the species. In conclusion, at the duration and intensity of infection that were employed, the effects of the deer ked on the measured physiological variables of the reindeer were insignificant.  相似文献   

6.
Knowledge of the internal life cycle of goat warble fly infestation is scarce despite ample data available on the aetiology, epidemiology, immunodiagnosis and treatment of such infestations. This study was carried out at the slaughterhouse of Rossano Calabro (Cosenza, southern Italy) on 154 animals from 10 months to 6 years of age from May 1997 to June 1998. 1206 Przhevalskiana silenus larvae were collected during the trial period from the subcutaneous tissue of the slaughtered animals. The larval stage average size ranged from 4.7 mm, for first instar larvae (May), to 16.6 mm, for third instar larvae (February), in the first cycle of infestation. No larvae were found in March-April, coinciding with the pupation period. Small first instar larvae were found at the beginning of the second cycle of infestation (May-June). Necroscopic examinations were also carried out on internal organs and no larvae were found. The results pointed out that the internal life cycle of P. silenus is exclusively subcutaneous and there is no internal migration of the larvae.  相似文献   

7.
Sixty yaks were autopsied to determine the migration pattern of warble fly larvae. In August, first instars were observed in the body of yak for the first time. These larvae peaked in number in October. From November to February, second instars were detected and their number peaked in January. Third instars appeared in January and peaked in March. Forty-five yaks were administered with ivermectin: 15 animals in September, 15 in October and 15 in November. Between December and June, the number of warbles was checked by palpation. Although some warbles were observed in the September- and November-treated groups, no warbles were detected in the October-treated group. Treatment of yaks with ivermectin was most effective for warble fly in October.  相似文献   

8.
Cross-reactivity between Hypoderma lineatum antigen and anti-Przhevalskiana silenus antibodies has been demonstrated by an ELISA technique. To evaluate the applicability of a commercial ELISA kit for the immunodiagnosis of goat warble fly infestation, different dilutions of serum and conjugate were tested, the development of antibody to P silenus in naturally infested goats was studied, and the results were compared with an ELISA technique using an antigen extracted from the first instar larvae of H lineatum. The best results were obtained with a serum dilution of 1:50; with both techniques the highest antibody concentration were recorded in October, November and December. In view of the confirmed cross-reactivity between H lineatum antigen and anti-P silenus antibodies, and the simplicity and rapidity of the assay, the commercial ELISA kit can be considered as a useful tool for the diagnosis of goat warble fly infestation.  相似文献   

9.
A total of 1276 cattle from 76 farms in 8 villages were examined by palpation of the skin for evidence of hypodermosis. The effects of age, sex, breed, and colour of cattle on hypodermosis were investigated. The overall prevalence was 31.9%. The mean number of warble fly larvae on infested animals was 8.46. Hypodermosis infestations were encountered in all the villages visited. Within a herd, the intensity of infestion decreased with the age of cattle. Infestation rates of warble fly larvae were lower in native cattle, in females, and in piebald animals.  相似文献   

10.
In September 2008, two ring-tailed lemurs (Lemur catta), comprising a mother-daughter pair, at the Greenville Zoo, Greenville, South Carolina, USA, were diagnosed with cuterebrid myiasis (Diptera: Oestridae) subsequent to sudden death of the adult lemur. On necropsy, a single bot warble was discovered in the subcutis of the axillary region. Histopathology revealed a severe eosinophilic bronchopneumonia. The juvenile lemur was inspected and found to have warbles on three separate dates in late September. One representative bot fly larva was identified as a Cuterebra sp. that normally infests lagomorphs in the southeastern United States. Cuterebrid myiasis is rarely reported in lemurs and has not been previously associated with pneumonia or death in these animals.  相似文献   

11.
Examination of 3,960 goats brought from six districts of Jammu province and slaughtered at Jammu abattoir from July 2005 to June 2006 revealed 47.22% prevalence of larval stages of warble fly (Przhevalskiana silenus Brauer, 1858) in goats. Highest prevalence was recorded in Udhampur (56.44%) and lowest in Doda district (13.49%). Classification of the study area into four zones based on height (meters above sea level), viz., zone I (300–325 m asl), zone II (325–800 m asl), zone III (800–1,500 m asl), and zone IV (>1,500 m asl), revealed significant (p < 0.01) difference in infestation among animals of zone II (71.68%), zone III (40.12%), and zone IV (22.41%). However, animals of zone I did not reveal any infestation. Statistical analysis in relation to age showed significant (p < 0.01) difference among different age groups, i.e., <1 year (2.81%), 1–3 years (51.17%), and >3 years (43.16%). Breed-wise analysis also showed significantly (p < 0.01) higher infestation rate among Bakerwali (51.51%) goats as compared to Beetal (42.59%). But no significant difference was recorded among male (47.81%) and female (46.82%) animals. The overall mean larva count (L1, L2, and L3) was observed to be 14.72 ± 0.34, ranging from 4 to 72. It was significantly (p < 0.05) higher in animals of zone II (22.20 ± 0.21) as compared to goats of zones III (14.21 ± 0.41) and IV (7.73 ± 0.90). Age-wise analysis of mean larva count also showed significant (P < 0.05) difference between animals of 1–3 years (16.25 ± 0.37) and >3 years of age (13.18 ± 0.40). Mean larvae count in relation to sex and breed did not reveal any significant difference. First-instar larvae (L1) were recorded from May to mid-September, second larval stage (L2) from mid-September to mid-December, and third-stage larvae (L3) from mid-December to February. However, No larvae were recorded from March to April, which is suggestive of pupation period in this region. Thus, it is concluded that adult fly is active in April to June. The results further confirmed that internal life cycle of P. silenus is subcutaneous and no migration of larvae occurs. This is the first report from India, based on slaughter house study on the prevalence and biology of goat warble fly infestation. It will help in devising suitable prophylactic and eradication program to check the economic losses rendered by adult fly.  相似文献   

12.
To screen the host-dependent abundance of hard tick (Acari: Ixodidae) developmental stages on ruminants in South Hungary, red and roe deer, as well as goats and sheep were examined in a season, when larvae and nymphs are active. Altogether 2271 ticks were collected. In the relevant period the prevalence of tick-infestation was significantly higher among goats, than among sheep kept in the very same area, most likely in association with the browsing habit of the former. Roe deer and goats were found to be important hosts for Ixodes ricinus and Haemaphysalis concinna larvae, in contrast to the view that this stage does not usually feed on medium-sized mammals. Interestingly, one third of I. ricinus larvae and one larva of H. concinna and of Dermacentor reticulatus collected from goats in the same herd in August have started the moulting process (showed apolysis) on their host, despite being three-host ticks. This is the first survey involving four species of domestic and wild ruminants in Europe to compare the host-preference of ixodid ticks in the same region.  相似文献   

13.
This study was conducted at the Xinglongshan Musk Deer Farm of China from July to September 2008. Results showed that captive male musk deer exhibit aggressive dominance behavior, by which a stable social ranking is established. Generally, there were three types of aggression in agonistic interactions among males: attacking, displacing and threatening. Threatening was more frequently observed than displacing and attacking. When in conflict with other deer, high‐rank males exhibited significantly more attacking than displacing and threatening. Moreover, no attacking occurred in low‐rank and middle‐rank males, but these individuals initiated significantly more threatening displays than high‐rank individuals. Among musk deer groups with different social ranks, there were no significant differences between threats received by middle‐rank and low‐rank groups, but attacks directed to high‐rank males was significantly lower than displacing and threatening behaviors. On the basis of these results, it is suggested that when a captive male musk deer population is assembled, individuals should be diversified in fighting ability and level of aggression. In particular, deer with higher aggression should not be enclosed with deer with similar tendencies, but should be enclosed with individuals with lower fighting levels. This should maintain stable social structures within captive musk deer groups and improve the overall welfare of captive musk deer.  相似文献   

14.
Unilateral chorioretinitis caused by ophthalmomyiasis interna posterior in a 5-month-old, female spayed Dachshund is reported. Larva removal by pars plana vitrectomy was performed after an unsuccessful photocoagulation of the organism. The larva was intact after surgical removal and was identified as a first stage instar Cuterebra spp. larva. The eye remains visual and comfortable with no signs of residual or recurrent inflammation postoperatively. This report describes, for the first time, the successful surgical retrieval of an intravitreal fly larva in a dog using vitrectomy techniques without sacrificing either the globe or vision, and taxonomic identification of the parasite.  相似文献   

15.
An adult quarter horse mare was presented with acute colic and fever. Physical examination and abdominocentesis showed septic peritonitis, and the mare was euthanatized. Necropsy and histopathologic examination revealed a focal partial perforation of the right ventral colon, which contained a single bot fly larva, identified as a third-instar larva of Gasterophilus intestinalis. This larva was embedded deep within the muscularis and the submucosa. Although bot fly larvae are known to attach to aberrant sites within the digestive tract, this is the first known report of deep penetration of the colon by a gasterophilus larva, with the resulting leakage of intestinal content leading to septic peritonitis.  相似文献   

16.
The field measures for the control and eradication of the warble fly in Northern Ireland are described. The level of infestation and the main economic losses before the introduction of these measures are indicated. The limitations of the control measures used before the introduction of systematic insecticides are discussed.A limited field trial with a systematic insecticide was conducted in 1964, but the main national programme for warble control was implemented in 1966 and 1967. Under the programme, the treatment of all cattle was compulsory.The nature and organization of the programme and its staffing and cost are described. The field monitoring, the extent and nature of adverse reactions in some of the treated animals, the effects on the rate of warble infestation, and the current status of “warbles” as a Notifiable Disease are discussed. Also described is the practicality of the eradication of cattle grubs from the Island of Ireland as a whole through synchronization of the warble control programmes in Northern Irelabnd and Eire.  相似文献   

17.
Chronic wasting disease (CWD) is a fatal disease of North American cervids that was first detected in a wild, hunter-shot deer in Saskatchewan along the border with Alberta in Canada in 2000. Spatially explicit models for assessing factors affecting disease detection are needed to guide surveillance and control programs. Spatio-temporal patterns in CWD prevalence can be complicated by variation in individual infection probability and sampling biases. We assessed hunter harvest data of mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) during the early phases of an outbreak in Saskatchewan (i.e., 2002-2007) for targeting the detection of CWD by defining (1) where to look, and (2) how much effort to use. First, we accounted for known demographic heterogeneities in infection to model the probability, P(E), that a harvested deer was infected with CWD given characteristics of the harvest location. Second, in areas where infected deer were harvested we modelled the probability, P(D), of the hunter harvest re-detecting CWD within sample units of varying size (9-54 km(2)) given the demographics of harvested deer and time since first detection in the study area. Heterogeneities in host infection were consistent with those reported elsewhere: mule deer 3.7 times >white-tailed deer, males 1.8 times>females, and quadratically related to age in both sexes. P(E) increased with number of years since the first detection in our study area (2002) and proximity to known disease sources, and also varied with distance to the South Saskatchewan River and small creek drainages, terrain ruggedness, and extent of agriculture lands within a 3 km radius of the harvest. The majority (75%) of new CWD-positive deer from our sample were found within 20 km of infected deer harvested in the previous year, while approximately 10% were greater than 40 km. P(D) modelled at 18 km(2) was best supported, but for all scales, P(D) depended on the number of harvested deer and time since the first infected deer was harvested. Within an 18 km(2) sampling unit, there was an 80% probability of detecting a CWD-positive deer with 16 harvested deer five years after the initial infected harvest. Identifying where and how much to sample to detect CWD can improve targeted surveillance programs early in the outbreak of the disease when based on hunter harvest.  相似文献   

18.
Hydatidosis is one of the most important zoonotic diseases with a worldwide distribution and it seems that the survival of Echinococcus granulosus in nature for many years, is due to having different mechanisms to escape from the host immune systems. One of these efficient mechanisms is the production of various antigens and proteins by the larva of the parasite and the main purpose of this study is evaluation of manifestation of various antigens in different parts of intermediate host. The hepatic and pulmonary hydatid cysts were gathered from sheep and the antigens of different parts of the cysts (laminated layer, protoscolices and cyst fluid) were separated and analyzed by SDS-PAGE and then transferred to nitrocellulose paper and finally, Western blot analysis was evaluated the immunogenicity of proteins. The antigens of laminated layer, protoscolices and hydatid cyst fluid, in different tissues of the liver and lungs, manifest various proteins and also these antigens are immunogenically different. Also, it is found more immunogenic proteins in the laminated layer than the other parts of the cysts. The various proteins are generated by Echinococcus granulosus larva depending on the type of tissues attacked by the parasite. Increasing the chance of survival may be the main cause of manifestation various antigens in different parts of cysts and host tissues. These antigenic variations might have made diagnostic serologic test unreliable.  相似文献   

19.
Between 1989 and 1997 different factors related to warble fly infestation (prevalence, intensity, climate, breed) were studied in north-eastern Algeria. Mean prevalence during the period was 76%. This figure was obtained from a cattle market survey of four different regions (Jijel, Constantine, Guelma, and El Tarf). One-hundred percent of the herds were found to be infested in El Tarf and 61% of animals were infested. Within a herd, the intensity of infestation decreased with the age of the cattle. The mean number of warbles per animal decreased as reinfestations occurred. The peak of the emergence of warbles observed between January and March was progressively delayed in the older animals. Two species of Hypoderma were present in cattle in Algeria (H. bovis and H. lineatum) with a predominance of H. lineatum (63%) in the semi-arid area (Batna) and a majority of H. bovis (75%) in humid area (Jijel). Warbles appeared earlier in Batna (October) than in Jijel (November). The Prim'Holstein breed was more susceptible to the warble fly infestation than Montbeliard or local breeds. The implementation of a control programme for hypodermosis in Algeria is urgent. Control can be achieved through a mass treatment of cattle. This approach must take into account the factors described in this study which influence the epidemiology of the disease.  相似文献   

20.
根据土源性寄生线虫体外发育期间受温度、湿度、季节和宿主动物影响的原理,采用电子计算机对上述因子和马歇尔线虫从虫卵发育到侵袭性幼虫的速度、数量进行分析回归,制定出模拟模型,设计出草场上该种线虫从虫卵发育到侵袭性幼虫数量的预测预报公式。将气象资料代入公式计算出侵袭性幼虫季节消长曲线,并与草场上羊体内成虫数量消长曲线相互对比。研究初步显示,可以采用气象资料通过计算机计算处理预测草场上马歇尔线虫侵袭性幼虫数量的季节动态,从而为制订防治措施提供科学依据。  相似文献   

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