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151.
Rahman MS Shohag AS Kamal MM Bari FY Shamsuddin M 《The Journal of reproduction and development》2012,58(2):219-222
The diameter of the preovulatory follicle (POF) and its effects on subsequent corpus luteum (CL) size and conception were studied in 38 lactating indigenous cycling buffaloes in the Mymensingh district of Bangladesh. Body condition score (BCS) at estrus was estimated for the buffaloes. The buffaloes were synchronized with two injections of a synthetic analogue of PGF2α administered 11 days apart. Transrectal ultrasonography was carried out at estrus and on days 5, 9, 12 and 16 post ovulation to determine the POF and successive CL size. Pregnancy was confirmed by ultrasound examination on day 40-45 post ovulation. Twenty one (55.3%) buffaloes were diagnosed as pregnant. The conception rates of thin (BCS ≤2.0), good (BCS 2.5-3.5) and fat (BCS glt;3.5) buffaloes were 7.7, 88.2 and 62.5% (χ2 = 19.54; P<0.05), respectively. The mean diameter of the POF at estrus was larger (P<0.01) in buffaloes that ultimately were diagnosed as pregnant compared with their nonpregnant counterparts (13.7 ± 0.3 vs. 11.2 ± 0.5 mm, respectively). The conception rates of buffaloes having small (9 to ≤ 12 mm), medium (>12 to ≤14 mm) and large (>14 to 16 mm) POFs at estrus were 9.1, 70.0 and 85.7% (χ2 = 13.87, P<0.01), respectively. On day 5 post ovulation, CL size was positively correlated (CL: r=.74, P<0.01) with POF diameter. Retrospective analysis revealed that on day 5 post ovulation, the pregnant buffaloes had higher (P<0.01) post ovulation CL sizes than their nonpregnant counterparts (15.6 vs. 11.8 mm). Similarly, on day 9 post ovulation, the difference in CL size (14.3 vs. 13.6 mm) between pregnant and nonpregnant buffaloes was significant (P<0.05). In conclusion, the diameter of the POF in buffaloes has a positive impact on the size of the post ovulation CL and conception. 相似文献
152.
Reasons for performing study: A consistent and clinically relevant model for the induction of core lesions confined to the mid‐metacarpal superficial digital flexor tendon (SDFT) has not been previously reported. Injection of bacterial collagenase is commonly used but often results in large, irregular and inconsistent lesions that disrupt the superficial tendon layers and epitenon. Objective: To develop and evaluate a new injection technique for collagenase induction of SDFT injury. Methods: Collagenase gel was injected into a physical columnar defect created by longitudinally placing a curved 16 gauge 8.89 cm needle in the mid‐metacarpal SDFT in a randomly selected forelimb of 10 horses. A placebo treatment injection was performed 1 week later. Serial ultrasound examinations were performed. Horses were subjected to euthanasia at 2 (n = 2), 4 (n = 2), 8 (n = 4) and 16 (n = 2) weeks post treatment injection. Post mortem magnetic resonance imaging and histological analysis were performed. Gene expression (18S, SCX, TNC, TNMD, COL1A1, COL3A1, COMP, DCN, MMP1, MMP3 and MMP13), total DNA, glycosaminoglycan and collagen content were determined for experimental tendons (n = 10) and unaffected tendons (n = 9). Results: Mid‐metacarpal SDFT core lesion induction was successful in all tendons with consistent lesion cross‐sectional area and minimal epitenon disruption. Histology confirmed loss of normal tendon architecture after tendonitis induction and subsequent healing of the tendon core lesion. Compared with gene expression in unaffected tendons, several tested genes were significantly upregulated (COL1A1, COL3A1, TNMD, SCX, TNC, MMP13), while others showed significant downregulation (COMP, DCN, and MMP3). Conclusion: Compared with the previously used direct injection of collagenase, this injection technique was easily performed and induced more consistent lesions that were mid‐metacarpal and did not disrupt the epitenon. Potential relevance: This model will allow for objective assessment of therapies for tendon regeneration in the mid‐metacarpal SDFT prior to clinical trials and routine clinical application. 相似文献
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Broom Mohammed Gabr Mohamed Hosny Al-Harbi Mamdouh Satheesh Sathianeson 《Aquaculture International》2021,29(6):2403-2414
Aquaculture International - In recent years, the demand for commercial sea cucumber diet increased due to the expansion of sea cucumber farming. In this study, we investigated alternative sources... 相似文献
155.
Seroprevalence and risk factors for bovine brucellosis in Jordan 总被引:1,自引:0,他引:1
Ahmad M. Al-Majali Abdelsalam Q. Talafha Mustafa M. Ababneh Mohammed M. Ababneh 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):61-65
We investigated the seroprevalence and risk factors for Brucella seropositivity in cattle in Jordan. The sera from 671 cows were randomly collected from 62 herds. The antibodies against Brucella were detected using a Rose Bengal plate test and indirect ELISA. A structured questionnaire was used to collect information on the cattle herds'' health and management. A multiple logistic regression model was constructed to identify the risk factors for Brucella seropositivity. The true prevalence of antibodies against Brucella in individual cows and cattle herds was 6.5% and 23%, respectively. The seroprevalence of brucellosis in cows older than 4 years of age was significantly higher than that in the younger cows. The seroprevalence of brucellosis in cows located in the Mafraq, Zarqa and Ma''an governorates was significantly higher than that of the other studied governorates. The multiple logistic regression model revealed that a larger herd size (odd ratio = 1.3; 95% CI: 1.1, 2.6) and mixed farming (OR = 2.0; 95% CI: 1.7, 3.7) were risk factors for cattle seropositivity to Brucella antigens. On the other hand, the use of disinfectants (OR = 1.9; 95% CI: 1.1, 2.1) and the presence of adequate veterinary services (OR = 1.6; 95% CI: 1.2, 3.2) were identified as protective factors. 相似文献
156.
Salicylic acid induced alleviation of oxidative stress caused by clethodim in maize (Zea mays L.) leaves 总被引:1,自引:0,他引:1
Deya Eldeen Mohammed Radwan 《Pesticide biochemistry and physiology》2012,102(2):182-188
Salicylic acid is used for regulation of oxidative stress in plants subjected to unfavorable environmental conditions. Application of herbicides for the purpose of weed killing can affect not only the weeds but also the main crop as well. Many herbicides have the ability to cause oxidative stress and further degradation of cell components. In this work, SA was used to alleviate the oxidative stress caused in response to clethodim herbicide in maize leaves. The results demonstrated that, spraying of clethodim caused yellowing of leaves and sometimes browning or drying of leaf tips with high clethodim doses. Contrary, leaves showed no injuries when treated with 1 mM SA 3 days prior clethodim application. Elevated amounts of H2O2 and MDA were detected in clethodim treated leaves compared with control indicating ROS formation and lipid peroxidation. Excessive ROS formation led to oxidative stress which followed by degradation of membranous structures. In SA treated leaves, the contents of H2O2 and MDA were more or less similar to the corresponding controls. A change in the antioxidant enzymes activities due to clethodim and SA treatment was noticed. For example, the activities of POD and APX were induced while SOD and CAT were more or less reduced in response to clethodim. SA treatment prior clethodim application could induce POD but inhibit CAT. Moreover, SOD and APX activities were adjusted to be similar to those of the control. Another mechanism of SA regulation of the oxidative stress occurred through the formation of antioxidants in the form of phenolic compounds. For that, spraying SA with or without clethodim could accumulate phenolic compounds greatly. The DPPH free radical scavenging assay for leaf extracts had confirmed a change in antioxidant status. Furthermore, SA could enhance accumulation of total proteins and free amino acids in clethodim and SA treated leaves compared with the control. This work was to provide evidence for the ability of SA to regulate clethodim herbicide detoxification through regulation of the antioxidant status of maize leaf cells. 相似文献
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159.
Background
Global climate warming can affect functioning of crops and plants in the natural environment. In order to study the effects of global warming, a method for applying a controlled heating treatment to plant canopies in the open field or in the greenhouse is needed that can accept either square wave application of elevated temperature or a complex prescribed diurnal or seasonal temperature regime. The current options are limited in their accuracy, precision, reliability, mobility or cost and scalability. 相似文献160.
A longitudinal study of 2-year duration was conducted to determine the risk, as measured by incidence rate, of Cryptosporidium parvum infection among dairy cattle in the Catskill/Delaware Watershed of New York City (NYC), and the factors that predispose animals to the likelihood of infection. A proportional sampling scheme with follow up at quarterly farm visits was employed for heifers and cows. Additionally, all calves born on the 39 study farms were sampled once during the first four weeks of life and at least once more before weaning. Samples were analyzed for the presence of C. parvum using a quantitative centrifugation concentration flotation technique and a C. parvum-specific enzyme-linked immunosorbent assay (ELISA). Of the 9914 fecal samples collected, 747 were found to contain C. parvum. The average number of oocysts detected was 1.3x10(5)/g (range: 1.0/g--8.2x10(6)/g). The average age at time of first detection of the organism was 15.0 days with a standard deviation of 6.59 days. The age range of animals infected with C. parvum in the study population was 3--60 days (inclusive). The unadjusted (crude) incidence rate of C. parvum among the entire study population was 2.05 per 1000 animal-days. The unadjusted incidence rate among pre-weaned calves was 15.55 per 1000 animal-days. After controlling for age and prior protozoal risk level, no seasonal impact on the incidence of C. parvum was detected among animals less than 61 days by negative binomial regression. A seasonal impact was identified among the oocyst counts of infected animals after controlling for age and prior protozoal risk level. 相似文献