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61.
Ditylenchus dipsaci, the stem nematode of alfalfa (Medicago sativa), Mycosphaerella pinodes, cause of Ascochyta blight in pea (Pisum sativum) and Aphanomyces euteiches, cause of pea root rot, result in major yield losses in French alfalfa and pea crops. These diseases are difficult to control and the partial resistances currently available are not effective enough. Medicago truncatula, the barrel medic, is the legume model for genetic studies, which should lead to the identification and characterization of new resistance genes for pathogens. We evaluated a collection of 34 accessions of M. truncatula and nine accessions from three other species (two from M. italica, six from M. littoralis and one from M. polymorpha) for resistance to these three major diseases. We developed screening tests, including standard host references, for each pathogen. Most of the accessions tested were resistant to D. dipsaci, with only three accessions classified as susceptible. A very high level of resistance to M. pinodes was observed among the accessions, none of which was susceptible to this pathogen. Conversely, a high level of variation, from resistant to susceptible accessions, was identified in response to infection by A. euteiches.  相似文献   
62.
Animal cruelty is defined as a deliberate action that causes pain and suffering to an animal. In Brazil, legislation known as the Environmental Crimes Law states that cruelty toward all animal species is criminal in nature. From 644 domestic cats necropsied between January 1998 and December 2009, 191 (29.66%) presented lesions highly suggestive of animal cruelty. The main necroscopic finding was exogenous carbamate poisoning (75.39%) followed by blunt-force trauma (21.99%). Cats from 7 months to 2 years of age were the most affected (50.79%). In Brazil, violence is a public health problem and there is a high prevalence of domestic violence. Therefore, even if laws provide for animal welfare and protection, animals are common targets for violent acts. Within a context of social violence, cruelty toward animals is an important parameter to be considered, and the non-accidental lesions that were found are evidence of malicious actions.  相似文献   
63.
Veterinarians diagnose marijuana toxicity based on clinical signs and history, or in conjunction with an over-the-counter (OTC) human urine drug screen. With the legalization of recreational marijuana use becoming more prevalent in the United States, a more accurate test to aid in the diagnosis of canine marijuana toxicity is needed. We collected urine and serum samples from 19 dogs with confirmed or suspected marijuana toxicosis from multiple veterinary hospitals and analyzed them with a novel UPLC-MS/MS method. Calibrations from 0.1 to 100 ng/mL and QC materials were prepared. Samples were extracted, purified, and eluted with solid-phase extraction. Urine samples were tested with an OTC human urine drug screen. The limit of detection (LOD) and lower limit of quantification (LLOQ) ranges for marijuana metabolites in serum were 0.05–0.25 ng/mL and 0.1–0.5 ng/mL, respectively. In urine, the LOD and LLOQ ranges for the metabolites were 0.05–0.1 ng/mL and 0.1–0.5 ng/mL, respectively. In serum, median and range of metabolite concentrations (ng/mL) detected included: THC, 65.0 (0.14–160); 11-OH-Δ9-THC, 4.78 (1.15–17.8); 11-nor-9-carboxy-Δ9-THC, 2.18 (0.71–7.79); CBD, 0.28 (0.11–82.5); and THC-glucuronide, 2.05 (0.72–18.3). In the 19 urine samples, metabolite: creatinine (ng: mg) values detected included: THC, 0.22 (0.05–0.74); 11-OH-Δ9-THC, 0; 11-nor-9-carboxy-Δ9-THC, 1.32 (0.16–11.2); CBD, 0.19 (0.12–0.26); THC-COOH-glucuronide, 0.08 (0.04–0.11); and THC-glucuronide, 0.98 (0.25–10.7). Twenty of 21 urine samples tested negative for THC on the urine drug screen. All 19 serum samples contained quantifiable concentrations of THC using our novel UPLC-MS/MS method. Utilizing a UPLC-MS/MS method can be a useful aid in the diagnosis of marijuana toxicosis in dogs, whereas using an OTC human urine drug test is not a useful test for confirming marijuana exposure in dogs because of the low concentration of THC-COOH in urine.  相似文献   
64.
Porcine teschovirus (PTV), Porcine sapelovirus (PSV) and Enterovirus G (EV-G) have been associated with enteric, respiratory, reproductive and neurological disorders. Although Brazil is the world’s fourth largest producer and exporter of pork, no information on the occurrence of PTV, PSV and EV-G infections is available for Brazilian pig herds. This study aimed to investigate the occurrence of Porcine enteric picornavirus infections in pig farms located in three distinct geographical regions of Brazil. Forty randomly selected diarrhoeic and normal consistency faeces of suckling (n?=?22) and nursery (n?=?18) pigs from farms located in 21 distinct cities of the Southern, Southeast, and Midwest regions of Brazil were evaluated by nested-RT-PCR assays. Suckling piglets presented the expected amplicon size for PTV (158 bp) and EV-G (313 bp) in single and mixed infections in 40.9 % (9/22) of the faecal samples. PSV amplicon (212 bp) was not detected in this age group. For nursery pigs, Porcine enteric picornaviruses amplicons were present in 77.8 % (14/18) of the faecal samples. PTV and EV-G were detected in single and mixed infections, while PSV was detected only in two samples in co-infection with PTV and EV-G in this age group. The Brazilian regions evaluated presented at least two of the tested viruses. Sequencing analysis revealed high similarities to the related viruses (95.3 to 99.2 % for PTV, 94.2 to 98.5 % for PSV and 86 to 100 % for EV-G). For the first time PTV, PSV and EV-G have been molecularly detected and characterised in pig faecal samples in Brazil.  相似文献   
65.
66.
Haemonchus contortus is the most prevalent nematode in Brazil. The objective of this study was to select 6 populations of H. contortus of known or suspected benzimidazole resistance status and characterize these using quantitative real-time polymerase chain reaction (qPCR) for single nucleotide polymorphisms (SNPs) F200Y, F167Y and E198A in the β-tubulin isotype 1 gene. qPCR was performed using DNA from a pool of 10 adult male H. contortus from a single animal per farm. Faecal egg count reduction test (FECRT) and egg hatch test (EHT) were used to determine the resistance status. Samples were obtained from 6 farms located in 5 counties in the Ceará State: Tauá, Boa Viagem, Quixadá, Santa Quitéria and Solonópole. The inbred-susceptible-Edinburgh (ISE) isolate was used as reference for comparative purposes in the qPCR. Benzimidazole resistance was detected by FECRT on all farms with efficacy values ranging from 0 to 51%. EC50 values as determined by EHT were all above 1.49 μg/ml. High frequencies of the resistant SNPs F200Y and F167Y alleles were detected but no resistance was detected at SNP E198A. Our results suggest that the SNPs F167Y and F200Y are both important for benzimidazole resistance in the studied populations.  相似文献   
67.
Strangulating obstruction of the small intestine by anomalous mesenteric bands is an uncommon cause of colic in horses. The most commonly reported bands are mesodiverticular bands that are embryological remnants of the vitelline arteries. Despite the congenital nature of the anomaly, a wide age range of horses can be affected. This report describes a case of small intestinal strangulating obstruction caused by an unusual, anomalous congenital band attached to the ileocaecal fold in a yearling colt. Information including case background, history, clinical, laboratory, surgical and pathological findings is described.  相似文献   
68.
Seven root-knot nematodes (RKN), including Meloidogyne exigua, M. incognita, M. paranaensis, M. enterolobii, M. arabicida, M. izalcoensis and M. arenaria are major pathogens of coffee crop in the Americas. Species-specific primers for their identification have been developed for five of them and constitute a fast and reliable method of identification. Here we report a PCR-based assay for specific detection of M. arabicida and M. izalcoensis. Random Amplified Polymorphic DNA fragments specific for these two species were converted into sequence characterized amplified region (SCAR) markers. PCR amplification using the SCAR primers produced a specific fragment of 300 bp and 670 bp for M. arabicida and M. izalcoensis, respectively, which were absent in other coffee-associated Meloidogyne spp. tested. SCAR primers also allowed successful amplification of DNA from single second-stage juveniles (J2), males and females. In addition, these primers were able to unambiguously detect the target species in nematode suspensions extracted from soil and roots samples, in different isolates of the same species or when used in multiplex PCR reactions containing mixtures of species. These results demonstrated the effectiveness of these SCAR markers and their multiplex use with those previously developed for M. exigua, M. incognita, M. paranaensis, M. enterolobii and M. arenaria constitute an essential detection tool. This diagnostic kit will contribute for specific J2 identification of the major RKN infecting coffee from field samples in the Americas.  相似文献   
69.
In view of the importance of venereal transmission of bovine leptospirosis, the objective of the present study was to apply the polymerase chain reaction (PCR) to 26 serovars of Leptospira interrogans, L. borgpetersenii, L. santarosai, L. noguchii and L. biflexa, to determine the detection threshold in semen samples and to evaluate the possibility of differentiation among serovars using 19 restriction endonucleases. The results showed that all serovars were amplified and the detection threshold in semen samples of a bull was 100 bacteria/ml. Using endonucleases we could classify the 26 serovars into eight groups. The present results show that PCR is a method of great potential for the detection of Leptospira spp. at bovine artificial insemination centers.  相似文献   
70.
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