Effect of open pulled straw (OPS) vitrification on the fertilisation rate and developmental competence of porcine oocytes

Freezing technologies are very important to preserve gametes and embryos of animals with a good pedigree or those having high genetic value. The aim of this work was to compare immature and in vitro matured porcine oocytes regarding their morphology and ability to be fertilised after vitrification by the open pulled straw (OPS) method. In four experiments 830 oocytes were examined. To investigate the effect of cumulus cells on oocyte survival after OPS vitrification, both denuded and cumulus-enclosed oocytes were vitrified at the germinal vesicle (GV) stage, then after vitrification they were matured in vitro. Besides, in vitro matured oocytes surrounded with a cumulus and those without a cumulus were also vitrified. The survival of oocytes was evaluated by their morphology. After in vitro fertilisation the rates of oocytes penetrated by spermatozoa were compared. Our results suggest that the vitrification/warming procedure is the most effective in cumulus-enclosed oocytes (22.35 +/- 1.75%). There was no difference between the order of maturation and vitrification in cumulus-enclosed oocytes, which suggests the importance of cumulus cells in protecting the viability of oocytes during cryopreservation.     

Artifactual changes in canine blood following storage, detected using the ADVIA 120 hematology analyzer

BACKGROUND: Artifactual changes in blood may occur as a consequence of delayed analysis and may complicate interpretation of CBC data. OBJECTIVE: The aim of this study was to characterize artifactual changes in canine blood, due to storage, using the ADVIA 120 hematology analyzer. METHODS: Blood samples were collected into EDTA from 5 clinically healthy dogs. Within 1 hour after blood sample collection and at 12, 24, 36 and 48 hours after storage of the samples at either 4 degrees C or room temperature (approximately 24 degrees C), a CBC was done using the ADVIA 120 and multispecies software. A linear mixed model was used to statistically evaluate significant differences in values over time, compared with initial values. RESULTS: The HCT and MCV were increased significantly after 12 hours of collection at both 4 degrees C and 24 degrees C, and continued to increase through 48 hours. The MCHC initially decreased significantly at 12-24 hours and then continued to decrease through 48 hours at both temperatures. Changes in HCT, MCV, and MCHC were greater at 24 degrees C than at 4 degrees C at all time points. A significant increase in MPV and a decrease in mean platelet component concentration were observed at all time points at 24 degrees C. Samples stored at 24 degrees C for 48 hours had significantly higher percentages of normocytic-hypochromic RBCs, and macrocytic-normochromic RBCs, and lower platelet and total WBC counts. CONCLUSIONS: Delayed analysis of canine blood samples produces artifactual changes in CBC results, mainly in RBC morphology and platelet parameters, that are readily detected using the ADVIA 120. Refrigeration of specimens, even after 24 hours of storage at room temperature, is recommended to improve the accuracy of CBC results for canine blood samples.     

Clinical value of carcinoembryonic antigen in mammary neoplasms of bitches

This study aimed at evaluating the behaviour and understanding the diagnostic value of the carcinoembryonic antigen (CEA) in bitches with mammary carcinoma as a tool for monitoring and prognosis of canine cancer patients. Serum samples from 77 bitches were divided into four groups, G1 (n = 21), control group (healthy/neoplasia free bitches); G2 (n = 31), bitches with non‐metastatic mammary carcinoma less than 3 cm; G3 (n = 12), bitches with non‐metastatic mammary carcinoma greater than 3 cm; and, G4 (n = 13) bitches with mammary carcinoma and lymph node metastasis. The marker was dosed once in G1, whereas in G2, G3 and G4, CEA levels were determined before (M0) and 15 days after (M1) mastectomy, using the ELISA kit for humans while reading used ELISYS ONE human. A group of 11 bitches was followed up 45 days after mastectomy (M2). The results for the concentration of markers in blood serum samples at the evaluated times and their relationship with neoplasia biological behaviour and observed clinicopathological changes were evaluated by the Tukey test at 5% significance. The ROC curve was established to find the cut‐off value and calculate the test sensitivity and specificity, the multivariate matching analysis was performed to confirm the association between CEA values and clinicopathological variables. CEA values increased significantly in bitches with mammary carcinoma, metastatic tumours with a diameter larger than 3.0 cm and high grade, compared with healthy ones. In addition, mastectomy reduced the CEA concentration in the blood (P < .05) whereas high CEA levels were associated with unfavourable prognostic factors (P < .05). The biomarker presented good diagnostic value, especially for more aggressive tumours. In conclusion, CEA serum concentrations allowed to follow efficiently the evolution of mammary tumours in bitches, since CEA values increased in bitches with mammary gland tumour and decreased after mastectomy while correlating with prognostic factors such as tumour size, nodal metastasis and histological grade. Further studies are still needed to confirm its diagnostic value for follow‐up of relapse and early metastasis.     

Arsenic and chromium resistance mechanisms in the Micrococcus luteus group

High arsenic (As) and chromium (Cr) concentrations are currently receiving attention because of their negative effects on the environment and human health. Microorganisms inhabiting contaminated environments have developed resistance mechanisms against the toxicity of these pollutants. Indeed, members of the bacterial genus Micrococcus have been isolated from different toxic metal-contaminated environments; however, knowledge concerning its resistance mechanisms to As and Cr toxicity remains lim...     

Biochar as a strategy to manage plant diseases caused by pathogens inhabiting the soil: a critical review

Phytoparasitica - The current agricultural scenario faces a range of challenges, with phytosanitary ones being paramount. In most cases, plant diseases are treated with chemicals; however, they...     

Enhancement of natural disease resistance in potatoes by chemicals

The mechanism involved in systemic acquired resistance (SAR) can be non-specifically induced in susceptible plants. In response to pathogens, plants' natural defence mechanisms include the production of lignin and phytoalexins and the induction of plant enzymes. The aim of this research was to study the induction of SAR mediated by the chemical activator DL-3-aminobutyric acid (BABA) and the fungicide fosetyl-aluminium in potato cultivars with different levels of resistance against Phytophthora infestans (Mont) de Bary. To study the chemical induction of the resistance, the foliage of several potato cultivars was sprayed with BABA, fosetyl-aluminium or water (as a control treatment). After 3 days the foliage was inoculated with P. infestans. Seven days after inoculation, development of disease symptoms in the foliage was assessed. In postharvest tuber samples, evidence for enhancement of the defence response was evaluated by measuring the protein content of several hydrolytic enzymes as well as the phenol and phytoalexin content. The highest level of protection against late blight was observed when the chemicals were applied at early stages of crop development. An increase in resistance to late blight was also detected in tubers after harvest. There was also an increase in the protein level of beta-1,3-glucanase and aspartic protease as well as in the phenol and phytoalexin content of potato tuber discs obtained from postharvest tubers of treated plants. Thus the protective effect seemed to persist throughout the whole crop cycle. This treatment may offer the possibility of controlling both foliage and tuber blight and could have a major impact in reducing over-winter survival of P. infestans in tubers.     

Evaluation of EDTA hematology tubes for collection of blood samples for tests of secondary hemostasis in dogs

OBJECTIVE: To evaluate the use of EDTA tubes for collection of blood samples for assays of secondary hemostasis in dogs. ANIMALS: 108 dogs of various ages, breeds, and sexes (19 healthy and 89 with abnormalities of secondary hemostasis). PROCEDURES: Blood samples were collected via cephalic venipuncture and transferred to sodium citrate tubes and EDTA tubes. Plasma was harvested from each type of tube for assays of concentrations of fibrinogen and D-dimer as well as prothrombin time, activated partial thromboplastin time, and antithrombin activity. Intra-assay and interassay precision and correlation coefficients for all hemostatic tests were calculated for each type of plasma sample. The effect of storage conditions on assay results for the 2 types of plasma samples was also evaluated. RESULTS: Results of hemostatic tests were highly correlated between citrated and EDTA-treated plasma samples. Intra-assay imprecision for all hemostatic tests with the exception of D-dimer concentration was < 10% for both citrated and EDTA-treated plasma samples; interassay imprecision was higher for EDTA-treated versus citrated plasma samples. Storage of plasma samples for 1 hour did not result in significantly different assay results for either type of plasma sample, but storage for 2 hours significantly affected values for EDTA-treated plasma samples. CONCLUSIONS AND CLINICAL RELEVANCE: Although evaluation of the sensitivity and specificity of hemostatic tests that use EDTA-treated plasma samples is required, EDTA may be a suitable alternative to sodium citrate as an anticoagulant for use in hemostatic testing in conditions in which tests could be performed within 1 hour after sample collection.     

Multicenter case-control study of risk factors associated with development of vaccine-associated sarcomas in cats

OBJECTIVE: To determine whether particular vaccine brands, other injectable medications, customary vaccination practices, or various host factors were associated with the formation of vaccine-associated sarcomas in cats. DESIGN: Prospective multicenter case-control study. ANIMALS: Cats in the United States and Canada with soft tissue sarcomas or basal cell tumors. PROCEDURE: Veterinarians submitting biopsy specimens from cats with a confirmed diagnosis of soft tissue sarcoma or basal cell tumor were contacted for patient medical history. Time window statistical analyses were used in conjunction with various assumptions about case definitions. RESULTS: No single vaccine brand or manufacturer within antigen class was found to be associated with sarcoma formation. Factors related to vaccine administration were also not associated with sarcoma development, with the possible exception of vaccine temperature prior to injection. Two injectable medications (long-acting penicillin and methyl prednisolone acetate) were administered to case cats more frequently than to control cats. CONCLUSIONS AND CLINICAL RELEVANCE: Findings do not support the hypotheses that specific brands or types of vaccine within antigen class, vaccine practices such as reuse of syringes, concomitant viral infection, history of trauma, or residence either increase or decrease the risk of vaccine-associated sarcoma formation in cats. There was evidence to suggest that certain long-acting injectable medications may also be associated with sarcoma formation.