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21.
Leptospirosis is a bacterial zoonosis of worldwide distribution and is endemic in tropical countries, where rodents and other wild mammals are abundant and may act as reservoirs. Leptospirosis has become a concern in captive wild animals, due mostly to their exposure to contaminated urine or environment. Although domestic cats (Felis catus) have been reported refractory to leptospirosis, serology and disease in captive wild felids is still unclear. In this study 57 adult, clinically healthy felids, including 1 Geoffroy's cat (Leopardus geoffroyi), 3 jaguarundis (Puma yagouaroundi), 17 margays (Leopardus wiedii), 22 little spotted cats (Leopardus tigrinus), and 14 ocelots (Leopardus pardalis) kept in captivity at the Sanctuary at the Itaipu Binacional hydroelectric power plant (Bela Vista Biological Sanctuary), Foz do Iguacu City, Paraná State, Brazil, were serologically surveyed for the presence of antibodies against 28 serovars of Leptospira spp. by microagglutination test (MAT). Two animals (3.5%) were seropositive: one male ocelot to the serovar Cynopteri (titer 100) and one female margay to Autumnalis (100) and Butembo (200). The captive-born, 5-yr-old ocelot had been solitary housed in an individual cage. The approximately 21-yr-old wild-caught margay was also kept individually. None of the tested animals showed signs ofleptospirosis. During a study conducted 4 yr previously in the same facility, this particular margay also tested positive for the same two serovars, among others. The present study indicates that the felids tested for Leptospira spp. by MAT were exposed to serovars, but did not demonstrate clinical signs of disease. Comparison with a previous study suggests that serovar titers may vary over time and that leptospirosis dynamics remains unclear in wild felids.  相似文献   
22.
Replication competent vaccines have been used successfully for the control of terrestrial rabies, mainly in wildlife; however, these vaccine strains occasionally may induce rabies. In this study, a pyrosequencing protocol for the rapid identification of vaccine-associated rabies viruses was applied to the 2008–2011 Italian epidemic. There was no evidence of vaccine-associated rabies cases following oral vaccination of foxes with the SAG2 and SADB19 vaccine strains.  相似文献   
23.
Insect bite hypersensitivity (IBH) is an equine skin allergy caused by bites of Culicoides spp. and impacts on the welfare of affected horses. The aim of this study was to identify and quantify risk factors for IBH. Data from 3453 Friesian horse mares and 7074 Shetland pony mares scored for IBH by inspectors during obligatory foal inspections were analysed using breed-specific multivariable logistic regression models. The combined effect of month and year of scoring, Province and inspector were significantly associated with IBH in both breeds. In Shetland pony mares, withers height and coat colour were also significantly associated with IBH, while body condition had a nearly significant effect. The outcomes from this study on risk factors might contribute to the development of more efficient measures to reduce the prevalence of IBH.  相似文献   
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CASE DESCRIPTION: A 3-year-old spayed female Labrador Retriever was evaluated for progressive lameness of the left forelimb 21 months after being shot in the elbow with a lead bullet. CLINICAL FINDINGS: Physical examination findings were consistent with moderate osteoarthritis of the left elbow joint. Orthogonal radiographic views of the elbow revealed multiple metallic fragments in and around the joint space as well as signs of osteoarthritis. TREATMENT AND OUTCOME: The elbow joint was evaluated arthroscopically. A lead-based bullet fragment was seen in the lateral synovial compartment and removed in multiple pieces. Excess fibrin and synovium were removed, and microfractures were created in exposed subchondral bone to stimulate neovascularization and fibrocartilage formation. In a follow-up telephone conversation 4 months after surgery, the owner reported a marked improvement in the lameness. CLINICAL RELEVANCE: Removal of lead intra-articular foreign bodies may be indicated even if the material is not believed to mechanically interfere with joint motion.  相似文献   
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The aim of the present study was to describe the strategies of the control of an outbreak of leptospiral infection in dairy cattle in Maranhão State, Northeastern Brazil. In the period from January to July 2015, 18 (17%) out of 106 cows presented abortion, six (5.7%) stillbirth, and 12 (11.3%) repeated estrus, totaling 24 animals with reproductive problems. The diagnosis of leptospirosis was based on serology (microscopic agglutination test—MAT), bacteriological culture, and polymerase chain reaction (PCR). Antibiotic therapy, vaccination protocols, and changes in management practices were suggested as control measures. Of all animals on the farm (n?=?280), 136 (48.6%) were seropositive for at least one serovar of Leptospira sp. No pure leptospiral culture was obtained. Eight of the animals with reproductive problems yielded positive PCR results (vaginal fluid of seven animals and urine and vaginal fluid of one animal). Genetic sequencing of a vaginal fluid/urine PCR-positive sample revealed Leptospira borgpetersenii. One year after the adoption of control measures, no reproductive problems were observed. Thus, leptospirosis probably caused the reproductive failures in the herd, and the control and prevention measures implemented were efficient in controlling the disease.

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27.
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment.  相似文献   
28.
Proteus spp. are widely recognized as opportunistic pathogens causing urinary tract and septic infections in humans and animals. The aim of this study was to investigate the prevalence of plasmid-mediated quinolone resistance genes and mutations in the quinolone resistance determining region in association with the detection of quinolone susceptibility of 24 strains of pet turtle-borne Proteus spp. Susceptibility of 4 antimicrobials including nalidixic acid, ciprofloxacin, ofloxacin, and levofloxacin was examined by disk diffusion and minimum inhibitory concentration test. Six isolates were resistant to nalidixic acid showing either intermediate resistance or resistance to other quinolones. All nalidixic acid, resistant isolates harbored mutations in gyrB (N440T/A401G/Q411S). Two of the isolates had both gyrA (S83I) and parC (S80I) mutations. Twenty-one isolates were positive for the presence of plasmid-mediated quinolone resistance genes; the qnrD gene had the highest prevalence with 19 (79.2%), while qnrS, qnrA, qnrB, and aac(6′), Ib-cr genes were present in 9 (37.5%), 2 (8.3%), 1 (4.2%), and 11 (45.8%) isolates, respectively. These results suggest that pet turtle-associated Proteus spp. should be considered a potential source of antimicrobial resistance determinants.  相似文献   
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Teleosts have many spawning strategies and the hormonal control of gametogenesis is not well defined among the species or even, between sexes. To increase the knowledge of gonadotropin hormones, we studied the trend by gene expression of gonadotropin receptors in the follicles and testis at different maturity stages in the European hake (Merluccius merluccius), a multiple-spawning species. With this aim, fshr and lhr were sequenced, characterized, and their gene expression was quantified in oocytes and in testes at different maturity stages. The deduced amino acid sequences were used to phylogenetic studies and evidenced that both receptors are phylogenetically closed to other gadoid species. The gene expression of both receptors was poorly expressed in primary follicles, increased in vitellogenic follicles and to later decrease in hydrated oocytes. In testis, highest levels of lhr were detected during spermiation, while levels of fshr were constant. For the first time, a histological analysis was performed in European hake testes showing an unrestricted lobular testis. To better elucidate the mechanisms involved in the oogenesis of the European hake, the expression of estrogen receptor and cyp19a was also investigated displaying high levels in all classes of follicles. All these data allow to increase the knowledge on reproductive physiology of an important socioeconomical species and it seeks to shed more light on the role of the receptors here studied during gametogenesis of multiple-spawning fish.  相似文献   
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