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1.
A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
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A sensitive and specific method is described for the simultaneous determination of oxytetracycline, tetracycline (TC), and chlortetracycline residues in edible swine tissues, by combining liquid chromatography with spectrofluorometric and mass spectrometry detection. The procedure involved a preliminary extraction with EDTA-McIlvaine buffer acidified at pH 4.0, followed by solid-phase extraction cleanup using a polymeric sorbent. The liquid chromatography analysis was performed with spectrofluorometric detection after postcolumn derivatization with magnesium ions. The limits of quantification were 50 microg/kg for muscle and 100 microg/kg for kidney tissues. The recovery values were greater than 77.8% for muscle and 65.1% for kidney. The method has been successfully used for the quantification of tetracyclines in swine tissues samples. The selective liquid chromatography mass spectrometric analysis for confirmation of oxytetracycline in one positive swine muscle sample was made by atmospheric pressure chemical ionization (APCI). The APCI mass spectra of the TCs gave the protonated molecular ion and two typical fragment ions, required for their confirmation in single ion monitoring scan mode in animal tissues.  相似文献   
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Due to the small volume of goat semen ejaculate, just a few doses of goat semen were produced when the sperm concentration is 100 × 10^/mL. The study was aimed to determine the viability of extended goat semen at refrigerated condition at 5 ℃ using varying sperm concentrations and evaluated if sperm concentration lower than 100 × 10^6/mL would affect the motility, viability and sperm morphology at refrigerated condition. Using an artificial vagina, ejaculated goat semen was collected from goat semen donor aged 1.5 year. Physical evaluation of the collected semen showed an average volume of 0.54 mL, mean pH of 6.8 and a milky white color with thick consistency indicative of high concentration. Fresh goat semen had an initial average of 76% with an average initial sperm concentration of 128 × 10^/mL. The semen was divided into four treatments: sperm concentration of 100× 10^/mL, 75 × 10^/mL, 50 × 10^/mL and 25 × 10^/mL, and were stored at 5 ℃ for a period of 10 d. The semen evaluation was performed for each of the four treatments every other day. Results showed that the sperm concentration of spermatozoa affected the duration of storage based on the sperm motility percentage, viability and morphology of spermatozoa. The extended goat semen with sperm concentration of 25 and 50 million sperm/mL is optimal for storage within 6 d that gave satisfactory percentage motile, viable and morphologically normal spermatozoa.  相似文献   
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The prevalence and risk factors for anti-Toxoplasma gondii antibodies were investigated in goats of the Seridó Oriental microregion, Rio Grande do Norte state, Northeast region of Brazil. Three hundred and sixty-six blood samples from goats collected by jugular venopuncture were used. For the serologic diagnosis of Toxoplasma gondii infection, the indirect fluorescent-antibody test (IFAT) with cut-off value 1:64 was carried out. The prevalence of anti-T. gondii antibodies was 30.6% [95% CI=25.9-35.6%] with titers ranging from 1:64 to 1:16,384. The multivariate logistic regression analysis showed that the risk factors associated to anti-T. gondii antibodies were presence of cats in the herd, extensive/semi-intensive management systems and lack of mineral supplementation.  相似文献   
8.
Until recently, Toxoplasma gondii was considered clonal with very little genetic variability. Recent studies indicate that T. gondii isolates from Brazil are genetically and biologically different from T. gondii isolates from USA and Europe. In the present study, we retyped 151 free range chicken isolates from Brazil including 117 newly isolated samples from 11 geographically areas (Alagoas, Bahia, Ceará, Maranh?o, Paraná, Pernambuco, Rio de Janeiro, Rio Grande do Norte, S?o Paulo, Sergipe, and Rondonia) and 34 previously reported isolates from the very north (Pará) and the very south (Rio Grande do Sul). Ten PCR-RFLP markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico were used to genotype all isolates. Overall analysis of 151 T. gondii isolates revealed 58 genotypes. Half (29/58) of these genotypes had single isolate and the other half of the genotypes were characterized with two or more isolates. Only 1 of 151 isolates was clonal Type I strain and 5 were clonal Type III strains. Two isolates had mixed infections. Clonal Type II strain was absent. One strain was Type II at all loci, except BTUB. The results confirm high genetic diversity of T. gondii isolates from Brazil.  相似文献   
9.
Neospora caninum was isolated from a naturally infected sheep from Brazil by bioassay in dogs. Approximately 70g of brain from each of two 4-month-old sheep with indirect fluorescent antibodies (>or=1:50) to N. caninum was offered to a different IFAT negative dog (Sheep n. 302, IFAT 1:400-Dog 1 and Sheep n. 342, IFAT 1:50-Dog 2). Parasite DNA was detected in both sheep brains using a PCR targeting the Nc-5 gene of N. caninum. Shedding of Neospora-like oocysts was noticed only in Dog 1, from 10 days post-inoculation (PI) to 25 days PI (a total of approximately 27,600 oocysts). Seventy days after infection, Dog 1 was euthanized and brain/cerebellum and medulla were collected and submitted to molecular methods, as were the oocysts, to confirm the identity of the isolate. Serum samples collected weekly from both dogs from the infection to the end of the experimental period had no antibodies anti-N. caninum by IFAT (<1:50). Oocysts, brain/cerebellum and medulla specimens of Dog 1 proved positive by a PCR assay targeting the Nc-5 gene of N. caninum. In addition, the oocysts have the DNA amplified by a PCR based on primers directed to the common toxoplasmatiid ITS1 sequence. The PCR products of ITS1 were sequenced, confirming again the isolate as N. caninum. Oocysts were also orally inoculated in two Swiss white mice two Mongolian gerbils (Meriones ungulatus) and two large vesper mice (Calomys callosus) (10(3)oocysts/animal). The rodents were sacrificed 2 months PI, and fresh preparations of brains showed Neospora thick-walled cysts in gerbil brains, but molecular detection using the Nc-5 PCR assay revealed DNA parasite in gerbil and also C. callosus brains. This is the first report of isolation and sequencing of N. caninum from a Brazilian sheep and the first report of molecular detection of N. caninum from C. callosus.  相似文献   
10.
Hunting behavior of a marine mammal beneath the antarctic fast Ice   总被引:1,自引:0,他引:1  
The hunting behavior of a marine mammal was studied beneath the Antarctic fast ice with an animal-borne video system and data recorder. Weddell seals stalked large Antarctic cod and the smaller subice fish Pagothenia borchgrevinki, often with the under-ice surface for backlighting, which implies that vision is important for hunting. They approached to within centimeters of cod without startling the fish. Seals flushed P. borchgrevinki by blowing air into subice crevices or pursued them into the platelet ice. These observations highlight the broad range of insights that are possible with simultaneous recordings of video, audio, three-dimensional dive paths, and locomotor effort.  相似文献   
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