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1.
A survey on coccidial infections in goats from central Spain was carried out. Fifty-five goat farms from 28 localities belonging to the three bioclimatic subregions of the area were visited. Individual samples (702) were obtained from the rectum of 130 young (under 1 year of age) and adult (572 over 1 year of age) goats. Coproscopical analyses showed a 100% prevalence and a moderate average intensity (7606.48 +/- 17918.78 Eimeria oocysts per gram of faeces), although wide variations were seen among herds and among individuals within each goat flock. Statistical analysis showed a strong age-related reduction in oocysts output in goats up to 4 years of age. The intensity of coccidial infections (young and adult goats, herds) was independent of the prevailing bioclimatic conditions. Heavier infections in young goats were found in bigger herds, whereas adult goats from these same big flocks (over 300 animals) showed the lowest oocyst output. Under our conditions, neither the female restocking rate nor the age structure seemed to play a significant role in the intensity of the Eimeria infections.  相似文献   
2.
Ticks are important ectoparasites of domestic and wild animals, and tick infestations economically impact cattle production worldwide. Control of cattle tick infestations has been primarily by application of acaricides which has resulted in selection of resistant ticks and environmental pollution. Herein we discuss data from tick vaccine application in Australia, Cuba, Mexico and other Latin American countries. Commercial tick vaccines for cattle based on the Boophilus microplus Bm86 gut antigen have proven to be a feasible tick control method that offers a cost-effective, environmentally friendly alternative to the use of acaricides. Commercial tick vaccines reduced tick infestations on cattle and the intensity of acaricide usage, as well as increasing animal production and reducing transmission of some tick-borne pathogens. Although commercialization of tick vaccines has been difficult owing to previous constraints of antigen discovery, the expense of testing vaccines in cattle, and company restructuring, the success of these vaccines over the past decade has clearly demonstrated their potential as an improved method of tick control for cattle. Development of improved vaccines in the future will be greatly enhanced by new and efficient molecular technologies for antigen discovery and the urgent need for a tick control method to reduce or replace the use of acaricides, especially in regions where extensive tick resistance has occurred.  相似文献   
3.
Ticks often cluster at preferred feeding sites on hosts, and the co-feeding of ticks at the same site has been shown to increase feeding success and the transmission of some pathogens. While the major route of infection of ticks with pathogens is via the bloodmeal during feeding on a parasitemic host, non-systemic transmission of viruses and spirochetes has been shown to occur from infected to uninfected ticks at common feeding sites on uninfected hosts. In this research, two separate studies were done using the tick-borne rickettsial pathogen of cattle, Anaplasma marginale. In one study we tested whether A. marginale could be transmitted non-systemically from infected to uninfected Dermacentor variabilis males while co-feeding on rabbits. Infection of ticks was determined by allowing them to transmission feed on susceptible cattle and by DNA probe and microscopy studies on salivary glands. In the second study, we tested whether the co-feeding of male and female ticks on parasitemic cattle would increase the acquisition and development of A. marginale in males. A. marginale infections in salivary glands were determined by quantitative PCR after the ticks were allowed to transmission feed on susceptible cattle. Non-systemic transmission of A. marginale did not occur from infected and uninfected ticks that fed at the same site on rabbits and, therefore, does not appear to be a means of A. marginale transmission. A. marginale infections in male ticks were not increased while co-feeding with females. Thus, co-feeding of adult Dermacentor spp. does not appear to influence the dynamics of A. marginale transmission.  相似文献   
4.
Faeces samples from 218, one to 30 days old, diarrheic dairy calves in 65 dairy herds were screened for the presence of rotavirus and concurrent infections with coronavirus, Cryptosporidium, F5+ Escherichia coli and Salmonella spp. Calves were grouped according to their age as follows: 1-7, 8-14, 15-21 and 22-30 days. Rotavirus infection was detected in 46.9%, 45.6%, 33.8% and 48.3% of the calves in the respective age-groups. No significant differences in the detection rate of rotavirus were found among calves on the different age-groups. Rotavirus was the only enteropathogen detected in 39 of the 93 (41.9%) diarrheic calves positive to this agent. Concurrent infections with other enteropathogen(s) were detected in 31.3%, 33.3%, 20.6% and 3.4% of the rotavirus infected calves in the age-groups 1-7, 8-14, 15-21 and 22-30 d, respectively. A significant age-associated decrease in the detection rate of mixed infections (p < 0.01) was found. The detection rates of the other enteropathogens considered in calves with rotavirus infection were 20.4% for coronavirus, 85.2% for Cryptosporidium, 16.7% for F5+ E. coli and 1.8% for Salmonella.  相似文献   
5.
Basic characteristics of European bison (Bison bonasus) semen were described and the efficacies of two extenders-Triladyl, containing egg yolk, and a synthetic extender, containing soybean lipids-were tested for semen cryopreservation. Seven ejaculates were collected by electroejaculation from a 10-yr-old, European bison bull. Each ejaculate was diluted at 37 degrees C to a final concentration of 200 x 10(6) sperm/ml with Triladyl or the synthetic extender. Extended semen samples were frozen according to a standard bull semen freezing protocol. After 2 wk of storage, one straw from each extender and ejaculate was thawed, and postthaw quality was evaluated by individual sperm motility and movement rate, numbers of sperm morphologic abnormalities and intact acrosomes, functional integrity of the sperm membranes determined by hypoosmotic swelling test (HOST), viability (live-dead, eosin-nigrosin stain), and a heterologous in vitro sperm penetration assay (SPA). A total of 600 in vitro-matured bovine oocytes were inseminated with 1 X 10(6) spermatozoa of Holstein semen frozen-thawed in Triladyl (control) or of European bison semen frozen in Triladyl or the synthetic extender. Nuclear status of the oocytes was determined after 18 h of sperm-oocyte coincubation. Extender had no effect on any evaluated parameters of semen after dilution and cooling (4 hr at 5 degrees C) or in postthaw individual motility, quality of movement, and sperm morphology. However, significantly (P < 0.05) higher numbers of spermatozoa with intact acrosomes, intact membranes (HOST), and viable sperm (P < 0.01) were in semen frozen in Triladyl than in the synthetic extender. Mean values for heterologous SPA for bull (control) and for bison semen frozen in the synthetic extender were very much alike-63.3+/-10.6% and 63.1 +/- 15.9%, respectively; bison semen frozen in Triladyl was lower, 43.0+/-24.2% but not significantly different. Cumulative results from a variety of viability assays of diluted/cooled and frozen-thawed semen, including the heterologous SPA, suggest that European bison semen can be successfully frozen in both extenders tested in this study.  相似文献   
6.
Lions (Panthera leo) are an endangered species threatened by illegal hunting, habitat loss, and infectious diseases. Little is known about the tick-borne pathogens that infect lions and could contribute to population declines. The objective of this study was to characterize Rickettsia spp., Anaplasma phagocytophilum, and Coxiella burnetii infections in 10 lions from the Fasano Safari Park in Italy by serology, polymerase chain reaction, and sequence analysis. Although animals did not show clinical signs of tick-borne diseases, evidence of infection with C. burnetii, spotted fever group Rickettsia sp., and A. phagocytophilum were found in 50%, 20%, and 10% of the lions, respectively. One of the lions tested positive for all three pathogens. This study is the first report of molecular evidence of infection with C. burnetii, Rickettsia sp., and A. phagocytophilum in lions and provides evidence that these felids become infected and serve as hosts for tick-transmitted bacteria.  相似文献   
7.
The feasibility of thoracoscopy for viewing the chest cavity and performing pulmonary lobectomy was assessed in 8 mongrel dogs. Previously, selective intubation had been performed in another group of dogs (n = 8) in order to monitor respiratory physiology and assess its safety. Each hemithorax was intubated using a double-barrelled endotracheal tube with one barrel placed in the left main bronchus and the other in the bifurcation of the trachea. The thoracoscope was introduced through a cannula inserted through a 2-cm incision at the ventral third of the left 5th intercostal space. The cranial, dorsal, and caudal surfaces of the pleura, lobes of the left lung, and the mediastinum were examined. A 2nd cannula was located in the dorsal 3rd of the 5th intercostal space with a prior incision and used for the introduction of forceps to separate the viscera. To biopsy, a 3rd cannula was inserted at the dorsal third of the 8th intercostal space with a prior incision, through which a 12-mm diameter stapler was introduced. Should a lobectomy be necessary, a 4th cannula is located in the middle third of the 4th intercostal space. Excision of the left caudal pulmonary lobe was performed through the incision made for the 12-mm diameter cannula (8th intercostal space); a twisting movement facilitated removal. Thoracoscopy is a procedure that can be used in dogs and is particularly suitable for examination, collection of biopsy specimens, and even lung lobectomies.  相似文献   
8.
9.
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.  相似文献   
10.
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