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1.
A possible association between the development of nontraumatic, acquired inguinal hernias (NAIH) and perineal hernias (PH) has been postulated in adult dogs. The objective of this study was to evaluate the frequency of concurrent diagnosis of PH in dogs presented with NAIH and determine potential risk factors for concurrent PH and NAIH. Medical records of adult male dogs presented for NAIH to 4 hospitals between 2007 and 2017 were retrospectively reviewed. Twenty-one dogs with NAIH were included, 8 of which had concurrent PH. There were no significant differences between dogs with and without PH; however, among dogs with both conditions, intact dogs (8.1 ± 1.4 years) were younger than neutered dogs (11.7 ± 1.0 years; P = 0.007). Thirty-eight percent of male dogs presenting for NAIH had concurrent PH, indicating that these conditions commonly occur together. Dogs presenting for NAIH should be carefully evaluated for concurrent PH before surgical intervention.  相似文献   
2.
To determine whether glucocorticoids affect the function of the bovine corpus luteum (CL) during the estrous cycle and early pregnancy, we examined the effects of exogenous cortisol or reduced endogenous cortisol on the secretion of progesterone (P4) and on pregnancy rate. In preliminary experiments, doses of cortisol and metyrapone (an inhibitor of cortisol synthesis) were established (n=33). Cortisol in effective doses of 10 mg blocked tumor necrosis factor-induced prostaglandin F(2α) secretion as measured by its metabolite (PGFM) concentrations in the blood. Metyrapone in effective doses of 500 mg increased the P4 concentration. Thus, both reagents were then intravaginally applied in the chosen doses daily from Day 15 to 18 after estrus (Day 0) in noninseminated heifers (n=18) or after artificial insemination (n=36). Pregnancy was confirmed by transrectal ultrasonography between Days 28-30 after insemination. Plasma concentrations of P4 were lower in cortisol-treated heifers than in control heifers on Days 17 and 18 of the estrous cycle (P<0.05). However, the interestrus intervals were not different between control and cortisol-treated animals (P>0.05). Moreover, metyrapone increased P4 and prolonged the CL lifespan in comparison to control animals (P<0.05). Interestingly, in inseminated heifers, cortisol increased the pregnancy rate (75%) compared with control animals (58%), whereas metyrapone reduced the pregnancy rate to 16.7% (P<0.05). The overall results suggest that cortisol, depending on the physiological status of heifers (pregnant vs. nonpregnant), modulates CL function by influencing P4 secretion. Cortisol may have a positive influence on CL function during early pregnancy, leading to support of embryo implantation and resulting in higher rates of pregnancy in heifers.  相似文献   
3.
On-farm augmentative releases of the parasitoid Habrobracon hebetor (Say) for controlling the millet head miner (MHM) Heliocheilus albipunctella (de Joannis) were tested in Burkina Faso, Mali and Niger from 2007 to 2009. In addition, a survey of farmers’ perceptions of insect pests, with particular focus on MHM, and the biological control program (BCP) was carried out. There was a significant increase of MHM parasitization rate after the releases, with up to 97% mortality. The survey on farmers’ perceptions revealed a fair knowledge of the MHM and the ability of farmers to describe the pest and the damage it caused. Farmers claimed that the biocontrol agent H. hebetor is effective and perceived a significant gain in grain yield due to this control strategy. Implications of these findings for a large extension of the MHM biocontrol program are discussed.  相似文献   
4.
Market-oriented production of gardening crops and cassava (Manihot utilissima) in the dry season is an increasingly frequent practice in Ségou, Mali. Traditionally, these crops are protected from roaming livestock with the help of dead fences. In order to provide a sustainable alternative to dead fences, the International Centre for Research in Agroforestry (ICRAF) began promoting the use of live fences, living trees planted closely together around a field plot. This study was conducted with the first farmers to use these live fences. These farmers expressed satisfaction with the protection offered by the trees and their ability to provide a variety of medicinal, economic, and food products. The form of land tenure, the social status of farmers within their families, and the availability of labour seem to be important factors in the decision to test the live fence. This raises questions about the accessibility of this technique and its possible contribution to the social and economic differentiation of its users. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
5.
Irrigation plays a fundamental role in world food provision but, to date, it has performed below expectations in Sub-Saharan Africa. The present study assesses and diagnoses the performance of 22 small and medium size community-managed irrigation schemes, mainly devoted to rice production, in different locations along the Mauritanian banks of the Lower Senegal River. The evaluations followed the Rapid Appraisal Process in which semi-structured interviews were held with representatives of the Cooperatives’ Boards in charge of each scheme to obtain information about the organisation of the cooperative, land tenure, irrigation system and organization, cropping pattern and soils. Additionally, for each irrigation scheme, the water-delivery service was characterized by making qualitative and comparative observations during field inspections; the pumping station's performance was diagnosed by a local specialist; the discharge at the head of the system was measured; daily irrigation time was recorded; and crop yields were determined by plot sampling. Then a set of performance indicators was computed. Water delivery capacity referred to irrigated areas was insufficient in a third of the schemes, and this insufficiency was exacerbated by poor maintenance. Irrigation intensity in habilitated areas was rather low being less than 0.66 in 50% of the schemes. The average productivity of land, irrigation water, and fuel (3.38 t ha−1, 0.30 kg m−3 and 2.37 kg kWh−1, respectively) were well below potential.  相似文献   
6.
This review is devoted to the study of the biological activity of polyether ionophores produced by bacteria, unicellular marine algae, red seaweeds, marine sponges, and coelenterates. Biological activities have been studied experimentally in various laboratories, as well as data obtained using QSAR (Quantitative Structure–Activity Relationships) algorithms. According to the data obtained, it was shown that polyether toxins exhibit strong antibacterial, antimicrobial, antifungal, antitumor, and other activities. Along with this, it was found that natural polyether ionophores exhibit such properties as antiparasitic, antiprotozoal, cytostatic, anti-mycoplasmal, and antieczema activities. In addition, polyethers have been found to be potential regulators of lipid metabolism or inhibitors of DNA synthesis. Further study of the mechanisms of action and the search for new polyether ionophores and their derivatives may provide more effective therapeutic natural polyether ionophores for the treatment of cancer and other diseases. For some polyether ionophores, 3D graphs are presented, which demonstrate the predicted and calculated activities. The data presented in this review will be of interest to pharmacologists, chemists, practical medicine, and the pharmaceutical industry.  相似文献   
7.
Sera obtained from dairy cattle in communal corral herds located near the city of Bamako in Mali, West Africa were sceeened using the microscopic agglutination test against 26 serovars representing 15 serogroups of Leptospira interrogans. Forty five percent (44.8%; 288/642) were positive to one or more serovars. This seroprevalence rate likely reflects infection since vaccination against leptospiral infection has not been practiced i Mali. The rate was higher among females. The most common titers were against antigens of serovars cynopteri (14.7%), hardjo (13.3%), pomona (9.2%), nona (8.1%), kambale (6.5%), grippotypyosa (6.4%), hebdomadis (6.2%), and pyrogenes (5.2%).  相似文献   
8.
An experiment was carried out in Burkina Faso to evaluate the potential for mechanical transmission of Trypanosoma vivax by the African tabanid Atylotus fuscipes. The experiment was carried out in a corral (10 m x 10 m) completely covered by a mosquito net (12 m x 12 m and 2.5m high). Eight heifers (cross-bred Zebu X Baoulé), free of trypanosome infection, were kept together with two heifers experimentally infected with a local stock of T. vivax. An average of 539 A. fuscipes per day, freshly captured with two Nzi traps, were introduced into the mosquito net from Day 1 to 20, to allow mechanical transmission of the parasites among cattle. Daily parasitological examinations (BCM) of cattle blood samples indicated that six of the eight receiver heifers were positive from days 9, 10, 15, 16, 19 and 29. Mechanical transmission of T. vivax by A. fuscipes was demonstrated unequivocally in close to natural conditions, at a high rate (75% incidence over a 20-day period) under a mean challenge of 54 insects per heifer per day. These results, in addition to previous demonstration of mechanical transmission of T. vivax by Atylotus agrestis, confirm that mechanical transmission can be a significant route of infection.  相似文献   
9.
10.
The present study compared the changes in isoflavones (daidzein and genistein) and their metabolite (equol and para-ethyl-phenol) concentrations in the blood plasma of cyclic and pregnant heifers after feeding with soy bean. Twelve healthy heifers were divided into three groups: cyclic heifers (days 8-12 of the estrous cycle; control group; n=4), an early pregnancy group (2 months pregnant; n=4) and a late pregnancy group (8 months pregnant; n=4). All heifers were fed a single dose of 2.5 kg of soy bean and then blood samples were taken from the jugular vein for 8 h at predetermined intervals. The concentrations of soy bean-derived isoflavones and their active metabolites were measured in the blood plasma on an HPLC system. In the blood plasma of the early- and late-pregnant heifers, we found lower concentrations and time-dependent decreases in daidzein and genistein in comparison to cyclic heifers (P<0.05). Moreover, we noticed significant increases of equol and para-ethyl-phenol in the blood plasma of the early-pregnant heifers (P<0.05). In contrast, in the blood plasma of the late-pregnant heifers, we did not find an increase in the isoflavone metabolite concentrations compared with the early-pregnant heifers (P>0.05). In conclusion, physiological status (cyclicity or pregnancy) of the females influenced the concentrations of isoflavone metabolites in the blood plasma of the heifers. The stage of pregnancy affects isoflavone absorption, biotransformation and metabolism differently and results in higher concentrations of active metabolites of isoflavones during early pregnancy in comparison to their lower concentrations during late pregnancy. Therefore, we surmise that cows are more sensitive to active isoflavone metabolite actions during early pregnancy than cyclic heifers and heifers in late pregnancy.  相似文献   
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