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61.
This study was conducted to measure the concentration of cefquinome in the endometrium of mares after intrauterine treatment and to evaluate associated inflammation. Mares (n = 14) were randomly assigned to one of the following groups: (i) control (n = 4) were either not treated (n = 2) or received (n = 2) lactated Ringer's intrauterine for 1 or 3 days; (ii) treated mares (n = 10) received intrauterine cefquinome for 1 or 3 days. After at least 10 days had passed following the last treatment and ovulation, mares were given Prostaglandin F2α (PGF2α) and were randomly assigned to an alternate treatment. Endometrial biopsy samples were taken at 2, 8, 24 and 48 h, or at 4, 12 and 36 h, after the last treatment. Biopsy samples were taken at the same time points from control mares (n = 2) and lactated Ringer-treated mares (n = 2). Cefquinome concentrations were quantified using a high-performance liquid chromatography (HPLC) assay and inflammation was assessed using haematoxylin and eosin (H&E)-stained sections. Concentrations of cefquinome [559 (1 day) and 595 μg/g (3 days) at 2 h, and 403 (1 day) and 370 μg/g (3 days) at 4 h] were similar between treatment groups at 2 and 4 h after treatment (p > 0.05). At 8 h, as well as at 24 and 48 h, concentrations were greater in the 3-day group (17 vs 301 μg/g, 3 vs 80 μg/g and 0.1 vs 0.2 μg/g, respectively) (p < 0.05). No significant differences (p > 0.05) in the inflammatory response at 2–48 h after treatment were found between groups. 相似文献
62.
Ataxia and paralysis in cats in Australia associated with exposure to an imported gamma-irradiated commercial dry pet food 总被引:1,自引:1,他引:0
Between June 2008 and March 2009, 87 cats in Australia developed symmetrical hindlimb ataxia, paraparesis, tetraparesis, paraplegia or tetraplegia in association with eating an imported, irradiated dry pet food. This communication reports the clinical signs and outcomes of those cats. 相似文献
63.
Y. Ben-Yephet D. Shtienberg M. Reuven Y. Mor 《European journal of plant pathology / European Foundation for Plant Pathology》1993,99(1):3-12
The response of carnation (Dianthus caryophyllus L.) cultivars toFusarium oxysporum f.sp.dianthi (F.o.d.) was evaluated in an artificially infested field from 1988/9 to 1991/2. Disease incidence was highly correlated with disease severity, indicating that disease incidence may be used to estimate the impact ofF.o.d. on the host. Based on the results, the following stepwise procedure was developed for characterizing the response of carnation cultivars toF.o.d. First, the general response of the tested cultivar was classified as resistant or susceptible on the basis of disease incidence values recorded 180 days after planting. Empirical analysis of the data revealed that a disease incidence level of 75% may be taken as a reliable cut-off point for separation of cultivars into the two groups. Within each group, cultivars were then subjected to a more explicit classification: in the resistant group the records of actual disease incidence were used for classification, while in the susceptible group the linear rearrangement of the disease progress curve was calculated according to the Gompertz function, and the value of the intercept was used for classification.Contribution No. 3539-E series, from the Agricultural Research Organization. 相似文献
64.
F López-Gatius P Santolaria JL Yániz JM Garbayo RHF Hunter 《Reproduction in domestic animals》2004,39(6):429-433
The incidence of early foetal loss is increasing under intensive management systems for dairy cattle. The aims of the present study were to determine whether there is any peak period of pregnancy loss during the early foetal period and to evaluate possible differences between single and twin pregnancies. The study population consisted of 1442 pregnant cattle from a single herd. Pregnancy was diagnosed by transrectal ultrasonography between 36 and 42 days after insemination, and then weekly until day 90 of gestation or until pregnancy loss. A total of 1310 cows (90.8%) bore single embryos and 132 (9.2%) carried twins. Pregnancy loss was registered in 139 (9.6%) cows before day 90 of pregnancy: 101 (7.7%) in single and 38 (28.8%) in twin pregnancies. The average time of pregnancy loss for all animals was 58.4 ± 12.6 days and ranged from 45 to 90 days. Seventy‐five per cent of the pregnancy losses were registered between 45 and 60 days of gestation. The average time of pregnancy loss for cows with singletons was 52.1 ± 4.1 days and ranged from 45 to 61 days and that for those with twins was 75.1 ± 12.4 days and ranged from 46 to 90 days. Seventy‐five per cent of the twin pregnancy losses were registered between 68 and 90 days of gestation. Our data show that the foetal loss in singleton pregnancies occurs earlier than in twin pregnancies. Assessment of normal development of gestation on days 60 and 90 after insemination is suggested. 相似文献
65.
JM Morrell B Persson H Tjellström A Laessker H Nilsson M Danilova PV Holmes 《Reproduction in domestic animals》2005,40(6):522-525
In the absence of commercially viable methods for cryopreserving turkey spermatozoa, new processing methods are required to extend the functional life of stored turkey spermatozoa for artificial insemination. The present study evaluates the efficacy of a new extender (Turkey Semen Extend) and investigates the use of density gradient centrifugation in processing turkey spermatozoa for artificial insemination. The new extender is compared with two commercially available turkey semen extenders, Beltsville Poultry Semen Extender and Ovodyl. Turkey spermatozoa in Turkey Semen Extend were still motile 20 h after collection, representing a considerable improvement over the other semen extenders (40%, 0% and 8% for Turkey Semen Extend, Beltsville Poultry Semen Extender and Ovodyl, respectively). A field trial on a commercial turkey farm showed improved fertilization rates following insemination of turkey hens with semen extended in Turkey Semen Extend (89.7%) compared with Beltsville Poultry Semen Extender (86.9%). This difference is statistically significant (p < 0.05). Processing on a density gradient, optimized for turkey spermatozoa, also increased sperm survival (50% gradient-prepared spermatozoa still motile after 18 h compared with <10% non-processed spermatozoa). Preliminary studies indicate that gradient preparation of spermatozoa may aid survival during cryopreservation. 相似文献
66.
C. Shoham G. Forer U. Mor J. Kern S. Cohen I. Harpaz Rachel Ben-Joseph Y. Antignus H. Czosnek S. Cohen R. Ber Rachel Ben-Joseph N. Navot D. Zamir Venezia Melamed-Madjar J. Hameiri M. Chen I. Ishaaya Zmira Mendelson M. J. Berlinger R. Dahan Sara Mordechi I. M. Seligman 《Phytoparasitica》1987,15(3):259-265
67.
Yigalelad Y. Ben-Yephet Michal Reuven L Mor Shulamit Manulis C. Shoham G. Forer M. J. Berlinger Lea Bar Nir D. Wool S. Cohen D. Veierov N. Aharonson Annie Fenigstein A. R. Horowitz N. C. Toscano D. Gerung Pnina Rapid D. Gerling Shalom W. Applebaum M. Klein B. Raccah R. G. Kenneth 《Phytoparasitica》1989,17(3):223-236
68.
MF Ponzio JM Busso M Fiol de Cuneo RD Ruiz AA Ponce 《Reproduction in domestic animals》2008,43(2):228-233
The cryopreservation of spermatozoa constitutes a valuable tool for the captive breeding management of valuable and/or threatened species. Chinchilla lanigera is a species almost extinct in the wild, and the domestic counterpart has one of the most valuable pelts in the world. The objectives of this study were to: (i) compare the functional activity of post‐thawed chinchilla spermatozoa cryopreserved at ?196°C either with glycerol (G) or ethylene glycol (EG) as cryoprotectants (1 m final concentration) and (ii) investigate the effects of incubating the gametes for 4 h in the presence or in the absence of the cryoprotectants; evaluations were performed taking into account motility, viability, response to hypo‐osmotic shock and acrosome integrity of the cells. Parameters reflecting post‐thaw (0 h) sperm functional activity were significantly lower than those of freshly ejaculated gametes. When comparing the cryoprotectant efficiency of G vs EG, neither cryoprotectant agent offered appreciable advantages. After 4 h of incubation, in the presence or absence of the cryoprotectant agent, a rapid and significant decrease was found in all functional parameters and remained at ~ 20–30% motile, viable and viable acrosome intact cells. Viability was significantly lower when the cryoprotectant was removed from the media (possibly due to the centrifugation process). With respect to the maintenance of sperm membrane integrity, only ~ 10% of cells showed membrane resistance to hypo‐osmotic conditions after the 4 h incubation period. These results constitute new insights for cryopreservation protocols and the development of assisted reproductive techniques in this species. 相似文献
69.
JM COX 《Australian veterinary journal》1995,72(3):108-115
SUMMARY: The world-wide clinical incidence of Salmonella Enteritidis has increased markedly. The increase is associated with the enhanced ability of the bacterium to systemically colonise layer chickens. Subsequent contamination and consumption of intact shell eggs from colonised layer hens, either directly or in foods containing raw or lightly cooked eggs, causes human disease. Despite investigation, no change in the biology of the bacterium has been correlated with increased colonisation in chickens. To date, no method of control at the production level has proven effective; consumer education is the best means of minimising the public health risk. 相似文献
70.