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431.
432.
We document three examples of fibropapillomatosis by histology, quantitative polymerase chain reaction (qPCR), and sequence analysis from three different geographic areas. Tumors compatible in morphology with fibropapillomatosis were seen in green turtles from Puerto Rico and San Diego (California) and in a hybrid loggerhead/ hawksbill turtle from Florida Bay (Florida). Tumors were confirmed as fibropapillomas on histology, although severity of disease varied between cases. Polymerase chain reaction (PCR) analyses revealed infection with the fibropapilloma-associated turtle herpesvirus (FPTHV) in all cases, albeit at highly variable copy numbers per cell. Alignment of a portion of the polymerase gene from each fibropapilloma-associated turtle herpesvirus isolate demonstrated geographic variation in sequence. These cases illustrate geographic variation in both the pathology and the virology of fibropapillomatosis.  相似文献   
433.
434.
Objective: To evaluate the hypothalamic–pituitary–adrenal (HPA) axis in MDR1‐1Δ (dogs with the MDR1 mutation associated with ivermectin sensitivity) and MDR1 wildtype dogs. Design: Prospective study. Setting: Institutional vivarium. Animals: Seven healthy Collie dogs. Measurements: MDR1 genotyping was used for allocation of dogs to 1 of 2 groups: dogs homozygous for the wildtype MDR1 allele (MDR1 wildtype) and those homozygous for the MDR1‐1Δ mutation (MDR1 mutant). Blood samples were obtained for determination of cortisol and adrenocorticotropin hormone (ACTH) concentrations under basal conditions, before and after ACTH administration, and before and after dexamethasone administration. Main results: Significant differences were identified between the MDR1 mutant and MDR1 wildtype groups. Basal plasma cortisol concentrations and cortisol concentrations after ACTH administration were significantly lower in MDR1 mutant dogs as compared with MDR1 wildtype dogs. Plasma ACTH concentrations after dexamethasone administration were significantly lower in MDR1 mutant dogs as compared with MDR1 wildtype dogs. Conclusions: Results suggest that P‐glycoprotein (P‐gp) plays a role in regulation of the HPA axis. Furthermore, it appears that the HPA axis in MDR1 mutant dogs that lack P‐gp is suppressed compared with MDR1 wildtype dogs. This finding may explain some clinical observations in breeds known to harbor the MDR1 mutation including Collies, Shelties, Australian Shepherds, and others. There is a clinical impression that many of these dogs have worse outcomes in response to stress and, at times, respond poorly to appropriate therapy. HPA axis suppression, secondary to the MDR1 mutation, could result in a relative adrenal insufficiency (RAI) state during times of stress or illness. Further studies are required to determine the relationship between the MDR1 genotype and RAI.  相似文献   
435.
Human visceral leishmaniasis, one of the most important zoonoses, is caused by the protozoa Leishmania chagasi (syn. L. infantum) and is present as a fatal disease common in South America and Europe where dogs and wild canids are the main reservoirs. A vaccine against visceral leishmaniasis would be an important tool in the control of this disease in dogs. Although the current strategies for vaccination against leishmaniasis are based on the use of recombinant antigens, killed vaccines are still attractive in terms of stability of their biochemical composition and antigenicity, cost, and safety. Here we evaluate the immunogenicity of a whole parasite vaccine as a promising candidate against canine leishmaniasis, demonstrated by cellular reactivity, changes in the cellular profile of the peripheral blood and by the differential production of immunoglobulins. Our results showed that immunization elicited mainly a strong cellular reactivity and increase in T-lymphocytes, particularly the subpopulation CD8(+) that would be related to the control of tissue parasitism. In addition, a higher production of anti-Leishmania total IgG, characterized by mixed isotypes profile (IgG1 and IgG2), was demonstrated.  相似文献   
436.

Objective

To compare the effects of alfaxalone and propofol, with and without acepromazine and butorphanol followed by doxapram, on laryngeal motion and quality of laryngeal examination in dogs.

Study design

Randomized, crossover, blinded study.

Animals

Ten female Beagle dogs, aged 11–13 months and weighing 7.2–8.6 kg.

Methods

The dogs were administered four intravenous (IV) treatments: alfaxalone (ALF), alfaxalone + acepromazine and butorphanol (ALF–AB), propofol (PRO) and propofol + AB (PRO–AB). AB doses were standardized. Dogs were anesthetized 5 minutes later by administration of alfaxalone or propofol IV to effect. Arytenoid motion during maximal inspiration and expiration was captured on video before and after IV doxapram (0.25 mg kg?1). The change in rima glottidis surface area (RGSA) was calculated to measure arytenoid motion. An investigator blinded to the treatment scored laryngeal examination quality.

Results

A 20% increase in RGSA was the minimal arytenoid motion that was detectable. RGSA was significantly less in ALF before doxapram compared with all other treatments. A <20% increase in RGSA was measured in eight of 10 dogs in PRO and in all dogs in ALF before doxapram. After doxapram, RGSA was significantly increased for PRO and ALF; however, 20% of dogs in PRO and 50% of dogs in ALF still had <20% increase in RGSA. A <20% increase in RGSA was measured in five of 10 dogs in PRO–AB and ALF–AB before doxapram. All dogs in PRO–AB and ALF–AB with <20% increase in RGSA before doxapram had ≥20% increase in RGSA after doxapram. Examination quality was significantly better in PRO–AB and ALF–AB.

Conclusions and clinical relevance

The use of acepromazine and butorphanol improved the quality of laryngeal examination. Any negative impact on arytenoid motion caused by these premedications was overcome with doxapram. Using either propofol or alfaxalone alone is not recommended for the evaluation of arytenoid motion.  相似文献   
437.
Zoonotic diseases, transmitted from animals to humans, are a public health challenge in developing countries. Livestock value chain actors have an important role to play as the first line of defence in safeguarding public health. However, although the livelihood and economic impacts of zoonoses are widely known, adoption of biosecurity measures aimed at preventing zoonoses is low, particularly among actors in informal livestock value chains in low and middle-income countries. The main objective of this study was to investigate knowledge of zoonoses and adoption of biosecurity measures by livestock and milk value chain actors in Bura, Tana River County, in Kenya, where cattle, camels, sheep and goats are the main livestock kept. The study utilised a mixed methods approach, with a questionnaire survey administered to 154 value chain actors. Additional information was elicited through key informant interviews and participatory methods with relevant stakeholders outside the value chain. Our results found low levels of knowledge of zoonoses and low levels of adherence to food safety standards, with only 37% of milk traders knowing about brucellosis, in spite of a sero-prevalence of 9% in the small ruminants tested in this study, and no slaughterhouse worker knew about Q fever. Actors had little formal education (between 0 and 10%) and lacked training in food safety and biosecurity measures. Adoption of biosecurity measures by value chain actors was very low or non-existent, with only 11% of butchers wearing gloves. There was a gendered dimension, evidenced by markedly different participation in value chains and lower adoption rates and knowledge levels among female actors. Finally, cultural and religious practices were shown to play an important role in exposure and transmission of diseases, influencing perceptions and attitudes to risks and adoption of biosecurity measures.  相似文献   
438.
Salmonellosis due to Salmonella enterica serovar Abortusovis (S. Abortusovis) is mainly characterized by abortion in sheep. Little is known about the immune response, which develops in the host as a result of infection. We evaluated the immune response of pregnant ewes vaccinated and successively exposed to full virulent S. Abortusovis. We found that vaccine constituted by inactivated S. Abortusovis induced both humoral and cellular-mediated immune response and that it provided protection against a challenge infection due to a fully virulent S. Abortusovis. Furthermore, we found an association between the lack of capability to produce IFN-gamma and abortion. This evidence suggests that protection against abortion can be associated to an IFN-gamma mediated mechanism. Our findings represent an interesting insight to better understand the interplay between host and S. Abortusovis and the effector mechanisms underpinning immune-based protection.  相似文献   
439.
A 13-year-old, castrated male Siamese cat was presented with a 4-month history of recurrent seizures and bilateral conjunctivitis and rhinitis. Computed tomography of the brain and nose revealed a cystic lesion in the cranial cavity that compressed the brain and invaded the nose. Nasal biopsy revealed a nasal adenocarcinoma. The cat was treated with intermittent antibiotics, phenobarbital, piroxicam, and chemoembolization; it survived for 2 years after diagnosis.  相似文献   
440.
Serum samples from 340 pet cats presented to three inner city clinics in Sydney Australia, 68 feral cats from two separate colonies in Sydney, and 329 cattery-confined pedigree and domestic cats in eastern Australia, were collected over a 2-year period and tested for antibodies directed against feline immunodeficiency virus (FIV) using immunomigration (Agen FIV Rapid Immunomigration test) and enzyme-linked immunosorbent assay methods (Snap Combo feline leukaemia virus antigen/FIV antibody test kit, IDEXX Laboratories). Western blot analysis was performed on samples in which there was discrepancy between the results. Information regarding breed, age, gender, housing arrangement and health status were recorded for all pet and cattery-confined cats, while the estimated age and current physical condition were recorded for feral cats. The FIV prevalence in the two feral cat populations was 21% and 25%. The majority of FIV-positive cats were male (60-80%). The FIV prevalence in cattery-confined cats was nil. The prevalence of FIV in the pet cat sample population was 8% (27/340) with almost equal prevalence in 'healthy' (13/170) and 'systemically unwell' (14/170) cats. The age of FIV-positive pet cats ranged from 3 to 19 years; all FIV-positive cats were domestic shorthairs with outside access. The median age of FIV-positive pet cats (11 years) was significantly greater than the median age of FIV-negative pet cats (7.5 years: P<0.05). The prevalence of FIV infection in male pet cats (21/172; 12%) was three times that in female pet cats (6/168; 4%; P<0.05). With over 80% of this pet cat population given outside access and continued FIV infection present in the feral population, this study highlights the need to develop rapid, accurate and cost-effective diagnostic methods that are not subject to false positives created by concurrent vaccination against FIV. This is especially important in re-homing stray cats within animal shelters and monitoring the efficacy of the new vaccine, which has not been challenged against Australian strains. The absence of FIV within cattery-confined cats highlights the value in routine screening and indoor lifestyles. This study provides cogent baseline FIV prevalences in three cat subpopulations which can be used for appraising potential disease associations with FIV in Australia.  相似文献   
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