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71.
72.
The objective of this study was to report our experience with an absorbable haemostatic gauze product in 20 horses with traumatic or surgical haemorrhage. The product is made from oxidised, regenerated cellulose (ORC) and is approved for external use and currently being studied to control internal bleeding in surgical settings in human subjects. Treated horses were from both practice and university settings. Signalment, anatomic location, underlying cause of bleeding and outcome were recorded in the medical record. The size of gauze, approximate time until bleeding stopped, and pre- and post-ORC adjunctive treatments were also recorded. The ORC was used in a variety of anatomic locations, including castration site, foot, flank incisions, distal limb, tooth extraction sites and the perineal region. The bleeding stopped or slowed dramatically within 90 s in 15 of 20 cases. There were no recorded complications in any of the cases. While this clinical report does not attempt to prove efficacy of the product in horses, it does show that this ORC product, which has been approved for use as a haemostatic agent in human subjects, is safe and of practical value, and may be a useful and viable option for the control of haemorrhage in a variety of equine clinical settings.  相似文献   
73.
The formation of zearalenone in a maize plot artificially infected with Fusarium culmorum was studied. The zearalenone concentration steeply increased only in the 8th week after inoculation and reached a maximum value of ca. 7 ppm, whereas zearalenone could not be detected in the control variants. The crude nutrient and dry matter content was not significantly influenced by the fungal infection. The infected crop showed average ear dry weights distinctly lower than that of the control variants (P less than or equal to 0.001). Apart from zearalenone, the mycotoxin deoxynivalenol was qualitatively detected in the infected maize. The toxicological relevance of the ascertained zearalenone content with regard to the health of dairy cattle and pigs was discussed.  相似文献   
74.
75.
Pathogenesis of Mycobacterium bovis infection in American bison   总被引:3,自引:0,他引:3  
Eighteen 12-month-old bison were randomly placed in each of 3 groups (6 animals/group): group-1 bison were exposed to live Mycobacterium bovis, group-2 bison were inoculated with killed M bovis in oil, and group-3 bison were noninfected controls. Six, 6-month-old, tuberculin test-negative calves were placed (pen contact) with group-1 bison 30 days after exposure to M bovis. Tuberculin skin test responses (caudal fold and/or comparative cervical) were detected in all bison in groups 1 and 2 at 2, 4, 6, 10, and 12 months. Tuberculin skin test responses were observed in 2 of 6 calves at 9 and 11 months after pen contact with M bovis-exposed bison (group 1). Statistically significant lymphocyte blastogenic responses to M bovis purified protein derivative were detected in group-1 bison exposed to live M bovis at 2 months after exposure (P less than 0.025). Significant ELISA reactions were detected in sera of bison at 2 months after exposure to killed M bovis in oil (P less than 0.005) and in bison 2 months after exposure to live M bovis (P less than 0.01). Significant tuberculin skin responses, ELISA reactions, or lymphocyte blastogenic responses to M bovis purified protein derivative were not observed in the 6 control bison. Grossly visible tuberculous lesions were observed in lymph nodes and/or lung collected at necropsy in 4 of 6 bison at 12 months after exposure to live M bovis. Microscopic granulomas compatible with tuberculosis were detected in 5 of 6 bison; M bovis was isolated from tissues of each of the 6 bison.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
76.
Six intact Balami rams were experimentally infected with Anaplasma ovis. Another six were infected one month after splenectomy and six others served as controls. Clinical manifestations of the disease, first observed between 5 to 7 days post-infection, were more severe and prolonged in the splenectomised-infected than in the intact-infected group. There was progressive deterioration in semen quality, which was also significantly more severe and prolonged in the splenectomised than in the intact-infected rams. Following treatment with long-acting terramycine, clinical recovery occurred earlier in the intact-infected (1–4 weeks) than in the splenectomised-infected group (5–7 weeks). A similar pattern was observed in post-treatment improvement in the spermiogram. However, although the infected animals recovered clinically by 1–7 weeks post-treatment, restoration of the reproductive potential did not occur for 20 to 25 weeks. It appears that stress factors may aggravate the deliterious effects of anaplasmosis.  相似文献   
77.
Parasitism in cattle is known to impair growth and development. Recent findings suggest that productivity of adult animals is also affected, but little is known about the physiological mechanisms involved. Furthermore, development of nematode resistance to drugs makes imperative the search of management practices that avoid whole herd treatment. We undertook an epidemiological and endocrine study in a grass based dairy farm in Argentina to study the effect of parasites on milk production and the underlying mechanisms involved, and identify individual animals that would benefit from antiparasitic treatment. All the cows in the dairy were followed monthly for egg parasite output in feces. Samples were cultured for genera determination. Milk production and reproductive results were recorded and periodical bleedings for hormone determination were performed. Nematode egg output (EPG) was maximal in late Summer and Autumn and minimal in Spring in coincidence with the Ostertagia inhibition-disinhibition cycle as this genus had the highest prevalence in all the study. The highest proportion of positive samples was found in the high producing herd and maximal counts were found in the peripartal period. Milk production did not correlate with EPG mean values but, when cows were grouped by EPG positivity around parturition, a significant difference in total milk production between EPG null and positive cows was observed. Positive cows produced 7%, 12% or 15% less milk than null EPG cows, depending on the sampling month/s chosen for classification. The highest difference was seen when both prepartum and postpartum samples were taken into account. No difference in lactation length and a marginal effect on partum to first service interval were encountered. Endocrine studies revealed a decrease in serum growth hormone (GH), type I insulin-like growth factor (IGF-I) and prolactin during lactation in cows with positive EPG in the first postpartum sample with respect to null EPG cows at that time. GH levels decreased and prolactin and IGF-I levels increased in both groups of cows from month 0 to 6 in milk. Serum insulin levels remained stable throughout lactation and were similar in both groups of cows. In conclusion, EPG around parturition may be a useful tool for identifying cows that will have a decrease in productivity due to parasite effects and would possibly benefit from an antiparasitic treatment. Besides, our results suggest that detrimental effect of parasites on milk production may be mediated by GH, IGF-I and prolactin serum levels.  相似文献   
78.
The objective of this study was to compare performance and aspects of adaptability attributes of cattle from a Florida Angus bloodline (local source from a mostly closed herd for over 50 yr) to cattle that are representative of modern Angus bloodlines (outside source) in US subtropical conditions. Embryos from both sources were transferred to Brahman-crossbred cows in South Florida, and calves (n=82) were born in 3 yr. Before weaning, summer tympanic temperatures were recorded hourly for 3 d in each year. Heifers were placed with fertile bulls until diagnosed pregnant. Traits relative to sexual maturation of bulls were recorded at 1- or 2-mo intervals until approximately 17 mo of age. Calves from outside sources had greater hip height at weaning than calves from the local source (P<0.001; 108.8 ± 0.62 and 104.7 ± 0.68 cm, respectively). Local-source calves (n=37) had greater (P=0.03) exit velocity (2.7 ± 0.3 m/s) than outside-source (n=45) calves (2.0 ± 0.29 m/s), which may be indicative of more nervous or temperamental disposition. However, no source differences were detected for other assessments of disposition (chute or pen score, P>0.8). Few source differences for minimum, maximum, or range of daily tympanic (inner ear) temperatures were detected. At 17 mo of age, outside-source heifers were heavier (P = 0.05) and had greater (P<0.001) hip height than Angus heifers from the local source. Heifers from the outside source were younger (P<0.001) at the time of their first conception (454 ± 17.5 d) than heifers from the local source (550 ± 16.9 d). Outside-source heifers also had greater (P<0.02) pregnancy and calving rates (0.7 ± 0.119 and 0.62 ± 0.125, respectively) from exposure to bulls within a year from weaning than the heifers from the local source (0.29 ± 0.089 and 0.19 ± 0.077, respectively). Bulls from the outside source were heavier (P=0.05) at 320 d of age than local-source bulls. From 14 through 17 mo of age, outside-source bulls had greater (P≤0.05) scrotal circumference and tended (P≤0.15) to be heavier than local-source bulls. There appeared to be no performance or adaptation advantages for the local-source Angus through 17 mo of age. The large source difference for age at first conception in heifers merits additional attention and comparison with cow lifetime production performance for the 2 sources.  相似文献   
79.
ABSTRACT: Although the importance of wild ruminants as potential reservoirs of bluetongue virus (BTV) has been suggested, the role played by these species in the epidemiology of BT in Europe is still unclear. We carried out a serologic and virologic survey to assess the role of wild ruminants in the transmission and maintenance of BTV in Andalusia (southern Spain) between 2006 and 2010.A total of 473 out of 1339 (35.3%) wild ruminants analyzed showed antibodies against BTV by both ELISA and serum neutralization test (SNT). The presence of neutralizing antibodies to BTV-1 and BTV-4 were detected in the four species analyzed (red deer, roe deer, fallow deer and mouflon), while seropositivity against BTV-8 was found in red deer, fallow deer and mouflon but not in roe deer. Statistically significant differences were found among species, ages and sampling regions. BTV RNA was detected in twenty-one out of 1013 wild ruminants (2.1%) tested. BTV-1 and BTV-4 RNA were confirmed in red deer and mouflon by specific rRT-PCR.BTV-1 and BTV-4 seropositive and RNA positive wild ruminants, including juveniles and sub-adults, were detected years after the last outbreak was reported in livestock. In addition, between the 2008/2009 and the 2010/2011 hunting seasons, the seroprevalence against BTV-1, BTV-4 and BTV-8 increased in the majority of provinces, and these serotypes were detected in many areas where BTV outbreaks were not reported in domestic ruminants. The results indicate that wild ruminants seem to be implicated in the dissemination and persistence of BTV in Spain.  相似文献   
80.
Background: Progesterone receptor (PR) antagonist aglepristone (RU534) has been used successfully for pregnancy termination and therapy of pyometra, vaginal tumors, and mammary hyperplasia in bitches and queens. All of these conditions share with canine mammary carcinomas the expression of PR. Objectives: To study the effect of RU534 on proliferation and apoptosis in canine mammary carcinomas in relation to PR expression. Animals: Twenty‐seven nonspayed bitches with mammary carcinomas were treated with either 2 doses of 20 mg/kg RU534 (n = 22, RU534‐treated group) or oil placebo (n = 5, control group) on days 1 and 8. Methods: Tumor samples were collected before (day 1) and after (day 15) treatment for immunohistochemistry. PR expression, proliferation index (PI), and apoptotic index (AI) were determined using antibodies against PR, Ki67, and cleaved lamin A/C antigens, respectively. The effect of treatment on these parameters was analyzed. Results: Differential expression of PR between day 1 (59.1% PR‐positive tumors) and day 15 (36.4% PR‐positive tumors) was observed in RU534‐treated tumors exclusively. After RU534 treatment, mean PI was significantly decreased in PR‐positive but unchanged in PR‐negative RU534‐treated tumors. A reduction of ≥20% in PI was found in 61.5% of RU534‐treated tumors with PR expression. Conversely, no effect on AI was observed after RU534 treatment. Conclusions and Clinical Importance: Neoadjuvant RU534 treatment had PR expression‐related inhibiting effects on proliferation of canine mammary carcinoma cells.  相似文献   
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