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A study was conducted to assess the effect of non-genetic factors on the reproductive performance of Sanga and Friesian?×?Sanga crossbred dairy cattle kept at Amrahia Dairy Farm, Ghana. Records on 66 crossbred Friesian?×?Sanga and 105 purebred Sanga cattle from 2005 to 2012 were used. The effect of sex of calf (male or female), season of calving (major, minor and dry), year of calving (2005–2012) and parity (first to third) on birthweight, calving interval and age at first calving were determined. The data were analyzed using the general linear model procedures of GenStat (Discovery Edition). The effect of parity of dam, year of calving, season of calving and sex of calf were considered as fixed effects for evaluating the different reproductive traits. Data on calving and conception rates over the period were 74.3 and 76.1 %, respectively. The overall mean values for birthweight, age at first calving and calving interval obtained were 23.9?±?1.5 and 22.8?±?1.4 kg, 38.8?±?2.5 and 40.2?±?2.4 months and 390.8?±?12.5 and 413.6?±?12.1 days for the crossbred and Sanga, respectively. It was observed that all the major determinants of reproductive performance studied apart from birthweight were significantly influenced by year of birth, parity, season of calving and sex.  相似文献   
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Results of molecular determination of a dog isolate of Neospora caninum in the Czech Republic are presented. Colorless bisporocystic oocysts measuring 10-13 micro m x 10-11 micro m were recovered from feces and used for DNA isolation. A diagnostic PCR procedure using previously described molecular methods was performed to determine the species. The N. caninum species-specific primers based on the Nc 5 region produced a positive result, while primers specific for Hammondia heydorni rDNA internal transcribed spacer 1 (ITS1) was negative. Sequencing and phylogenetic comparison of ITS1 rDNA and the D2 domain of the large subunit rDNA (D2 LSU) determined our isolate to be N. caninum. Phylogenetic analysis of closely related genera Toxoplasma, Neospora and Hammondia based on ITS1 and D2 LSU robustly distinguished three clades: (i). Toxoplasma gondii + Hammondia hammondi, (ii). N. caninum + Neospora hughesi, and (iii). H. heydorni. Based on phylogenetic relationships we propose three acceptable suggestions to solve the problem of taxonomy of these genera.  相似文献   
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This study evaluates the antioxidant capacity of 14 herbs/spices from Cameroon. Freeze-dried samples extracted in methanol (free or unconjugated polyphenol) and in 1.2 M hydrochloric acid (HCl) in methanol (total antioxidant that is both unconjugated and conjugated) were analyzed using two different antioxidant assay methods [Folin-Ciocalteu reagent (Folin) and the ferric reducing antioxidant power (FRAP)]. The 1.2 M HCl in methanol extracts had significantly higher (P < 0.001) antioxidant capacities than the methanolic extract. Generally, the FRAP antioxidant values were significantly (P < 0.001) higher than the Folin antioxidant values. Although a significant correlation (P < 0.05) was obtained between the Folin phenol and the FRAP antioxidant, the trends of the antioxidant capacity of the samples were different for the Folin and FRAP methods. The leaves of the Piper species top the total antioxidant tables in both Folin and FRAP assay methods, respectively. Irvingia gabonensis tops the FRAP free antioxidant list, while Piper umbellatum leads the Folin free antioxidant followed by Thymus vulgaris. Thus, the antioxidant capacity of plant samples determined by different methods should be interpreted with caution. However, irrespective of the assay method used, the samples were rich in antioxidants.  相似文献   
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Increasingly complex networks of small RNAs act through RNA-interference (RNAi) pathways to regulate gene expression, to mediate antiviral responses, to organize chromosomal domains, and to restrain the spread of selfish genetic elements. Historically, RNAi has been defined as a response to double-stranded RNA. However, some small RNA species may not arise from double-stranded RNA precursors. Yet, like microRNAs and small interfering RNAs, such species guide Argonaute proteins to silencing targets through complementary base-pairing. Silencing can be achieved by corecruitment of accessory factors or through the activity of Argonaute itself, which often has endonucleolytic activity. As a specific and adaptive regulatory system, RNAi is used throughout eukarya, which indicates a long evolutionary history. A likely function of RNAi throughout that history is to protect the genome from both pathogenic and parasitic invaders.  相似文献   
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A study was undertaken to investigate and mitigate the risk from zoonotic Cryptosporidium associated with dairy farming in Dagoretti division, Nairobi, Kenya. Outcome mapping (OM), a relatively new tool for planning and evaluation, was used to foster and then monitor changes in farmer management of health risks. Elements of the OM framework, including the vision, mission and expected progress markers, were developed in participatory sessions and a set of progress markers was used for monitoring behaviour change in farmers participating in the project (the boundary partners). Behaviour change (the outcome challenge) was supported by a range of awareness and educational campaigns, working with strategic partners (extension agents and administrative leaders). The farmers the project worked with made considerable progress according to the markers; they demonstrated an understanding of cryptosporidiosis, established or maintained clean and well drained cattle sheds, and took conscious effort to reduce possible infection. Farmers who did not participate in the project (non-contact farmers) were found to be less advanced on the progress marker indicators. Non-contact farmers who carried out risk-reducing practices had done so independently of the project team. The administration leaders, as strategic partners, had a positive attitude towards the project and confidence in their ability to support project objectives. The study demonstrates the utility of OM in helping to identify and support behavioural change.  相似文献   
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Objective— To compare short‐ and long‐term outcome and complications of chest wall reconstruction in dogs using autogenous, prosthetic, and composite autogenous–prosthetic techniques. Study Design— Historical cohort. Animals— Dogs (n=44) with spontaneous tumors arising from or involving the chest wall. Methods— Medical records were reviewed for dogs with rib and/or sternal tumors treated by chest wall resection and reconstruction. Signalment, preoperative clinical features, intraoperative findings and complications, reconstruction technique (autogenous muscle flap, prosthetic mesh, or composite autogenous–prosthetic technique), and short‐ (≤14 days) and long‐term (>14 days) postoperative complications were determined from the medical records and telephone contact with owners and referring veterinarians. Associations between chest wall reconstruction technique and postoperative complications were tested with Cox proportional hazards. Results— Chest wall defects were reconstructed with autogenous muscle flaps (29 dogs), prosthetic mesh (3), and a composite technique of prosthetic mesh and either autogenous muscle or omental pedicle flap (12). Early postoperative complications were recorded in 8 dogs (18.2%) and included seroma (5) and pleural effusion and peripheral edema (3). One dog had a late complication (2.3%) with a mesh‐related infection 767 days postoperatively. Overall, complications occurred in 10.3% of autogenous, 25.0% of composite, and 66.7% of prosthetic reconstructions. Chest wall reconstruction with Marlex mesh alone was associated with a significantly increased risk of postoperative complications compared with autogenous reconstruction (P=.027). Reconstruction of sternal defects (3), 2 of which were performed with Marlex mesh alone, was associated with a significantly increased risk of complications compared with lateral chest wall reconstructions (P=.037). Conclusions— Large chest wall defects can be reconstructed with autogenous and composite techniques, but prosthetic mesh should be covered with well‐vascularized autogenous muscle or omentum to decrease the risk of postoperative complications. Sternal defects should be reconstructed with rigid techniques. Clinical Relevance— Chest wall reconstruction with autogenous muscle flaps or a combination of autogenous techniques with prosthetic mesh is associated with a low rate of infection and other complications.  相似文献   
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