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We evaluated the prevalence of mycobacterial infections (i.e., Mycobacterium bovis and non-tuberculous mycobacteria [NTM]) and their associated risk factors among cattle herds and trade cattle in southwestern Nigeria. Through cross-sectional study design, cattle herds from three locations were screened using the single intradermal comparative cervical tuberculin test based on two diagnostic standards; more than 4 mm (? 4 mm) and more than 2 mm (? 2 mm) cut-off points. Abattoir study involved screening trade cattle for tuberculous lesions. Overall, 515 cattle from 45 herds were screened. Using >?4 mm, animal level and herd prevalence of 11.7 and 46.7% were recorded, respectively. Applying the ? 2 mm cut-off, animal level and herd prevalence increased to 31.1 and 60.0%, respectively. Significantly, using the ? 2 mm cut-off, cattle in medium size herds/extensive management system (OR?=?1.6; 95% CI 1.1–2.5) and Sokoto Gudali (OR?=?2.3; 95% CI 1.4–3.8) were more at risk of being positive reactors, while Rahaji (OR?=?0.3; 95% CI 0.1–0.7) breeds of cattle and cows in the peri-urban area (OR?=?0.4; 95% CI 0.2–0.9) were less at risk of being positive reactors. Again, M. avium reactor of 21.7% was observed. In the abattoir, 1797 cattle were examined with 126 lesions suggestive of tuberculosis (TB). Culture/molecular analyses confirmed 2.2% M. bovis and 0.9% NTM infections. Risk factors associated with bovine TB among trade cattle were sex (OR?=?4.0; 95% CI 1.2–13.5) and age (OR?=?0.3; 95% CI 0.1–0.9). We confirm 11.7% prevalence of mycobacterial infections among populations of cattle screened with breed and herd size being major risk factors.  相似文献   
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ObjectiveTo evaluate the influence of premedication with tramadol on xylazine–ketamine anaesthesia in young pigs.Study designProspective, randomized, blinded cross-over study.AnimalsTen young Niger hybrid pigs: mean weight 6.1 ± 0.6 kg.MethodsPigs were anaesthetized twice. Xylazine (2.5 mg kg?1), ketamine (25 mg kg?1) and atropine (0.04 mg kg?1) were administered by intramuscular (IM) injection, 5 minutes after either tramadol (5 mg kg?1)) (treatment XKT) or saline (treatment XKS). Time to loss of righting reflex (TLRR), duration of antinociception, duration of recumbency (DR) and recovery times (RCT) were recorded. Quality of induction of anaesthesia including ease of endotracheal intubation was assessed using a subjective ordinal rating score of 1 (worst) to 4 (best). Heart, pulse and respiratory rates, arterial oxygen saturations and rectal temperatures were determined over 60 minutes. Antinociception was assessed by the pigs’ response to artery forceps applied at the interdigital space. Data were compared with Student's t-test, Mann–Whitney's test or analysis of variance (anova) for repeated measures as appropriate and are presented as mean ± standard deviation.ResultsThe quality of anaesthetic induction was significantly better and duration of antinociception significantly longer (p < 0.05) in treatment XKT (3.1 ± 0.7 score; 43.7 ± 15.5 minutes) than in treatment XKS (2.8 ± 0.6 score; 32.0 ± 13.3 minutes). TLRR, DR and RCT did not differ significantly (p > 0.05) between treatment XKT (2.1 ± 0.8, 65.8 ± 17.0 and 13.2 ± 6.7 minutes) and treatment XKS (2.1 ± 1.3, 58.0 ± 14.8 and 10.3 ± 5.6 minutes). Physiological measurements did not differ between the treatments.Conclusion and clinical relevanceTramadol improved the quality of anaesthetic induction and increased the duration of antinociception in xylazine–ketamine anaesthetized young pigs without increasing duration of anaesthesia, nor causing additional depression of the physiological parameters measured.  相似文献   
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Nodule formation in legumes is a process that starts with root infection by rhizobia. The present study assessed the population and infectivity of the indigenous rhizobial strains in rainforest soils of Nigeria. Soils were collected from three sites – Idi-Ayunre, Orile-Ilugun (OI) and the University of Ibadan Teaching and Research Farm (UITRF) – and analysed for physico-chemical properties and rhizobial population. Soybean varieties TGx1448-2E and TGx1456-2E and a cowpea variety IT89KD-288 were planted as trap crops on each of the soils, and rhizobia were isolated from their nodules. Infectivity assay was conducted using eight varieties of soybean and a cowpea variety. Most probable number estimate of the rhizobial population showed that the UITRF had significantly higher rhizobial population than the other two locations. OI and the UITRF soils planted with TGx1448-2E had significantly higher nodules and number of strains than other treatments. Among the 70 slow-grower strains isolated, only nine were infective. Three of the nine strains – IDC8, TRC2 and OISa-6e – nodulated at least seven of the eight soybean varieties used for infectivity test. Indigenous rhizobial infectivity of the studied locations was low, and cultivation of grain legume may require rhizobial inoculation for high productivity.  相似文献   
4.
The deficiency of potassium (K) has resulted in decreasing the yield and quality of food grains. Moreover, with decreasing water resources the use of wastewater in agriculture as an alternative source of water and nutrients is being debated. This study was therefore undertaken to test wastewater for its suitability as irrigation water together with uniform basal doses of nitrogen (N) and phosphorus (P) and varying doses of potassium (K0, K20, K40 and K60). It was observed that the plants receiving wastewater as a source of irrigation water performed better with a lower K dose. Potassium at 20?kg?ha?1 along with wastewater resulted in better growth, photosynthetic rate (P N), stomatal conductance (g s) and yield of the chickpea (Cicer arietinum L.). Thus fertilizer rates could be lowered with the use of wastewater which can serve not only as the source of water but of nutrients also. However, regular monitoring of wastewater and soil for any buildup of heavy metal is necessary. The physical and chemical parameters of wastewater were also tested and most of them were found to be well within the permissible limits as set by the Food and Agriculture Organization (FAO).  相似文献   
5.
Climate change, urbanization, and population increase limit food availability. To sustain human existence, there is the need to increase food and agricultural production to mitigate the impact of these factors. Scientists have been working for years on ways to increase food production. From plant breeding techniques to soil science, scientists have made tremendous progress. The rhizobiome has been proven to be important to crop production, and the impact of the rhizobiome on plant health cannot be overemphasized. Being rich in diverse complex microbial interactions, the rhizosphere has become a major force in recent plant growth promotion studies. The upsurge in next-generation sequencing applications with the various “omics” technologies is helping to unearth information relating to rhizosphere impact on plant growth. Explaining the complex interactions between and across microbial species present in the rhizosphere is important to further enhance our understanding of their mechanistic and mutualistic functions. Knowledge from this can be used in rhizosphere biome engineering for improved plant growth and yield in the face of the various biotic and abiotic challenges.  相似文献   
6.
Early‐stage indicators of the African catfish Clarias gariepinus (Burchell) (egg fertilization and hatching rates, larval survival rate and time to hatch) were assessed in aqueous solutions of NPK 15‐15‐15 and layer manure. Recommended use rates (RUR) of NPK 15‐15‐15 and layer manure have volume‐equivalent of 15 mg/L and 28 mg/L respectively. Solutions containing *0.7RUR, *1.0RUR and *1.5RUR dilutions were used as treatments within‐fertilizer. There were significant differences in pH, dissolved oxygen (DO), total hardness and total metal levels in treatments of NPK (p < 0.0001) and layer manure (p < 0.0001). Fertilization, hatching rate and larval survival were significantly lower while incubation was significantly longer in treatments of NPK (p < 0.001) and layer manure (p < 0.0001) in comparison with control. In NPK treatments, the indicators correlated with pH (r ?0.96 to ?0.98, p < 0.0001), with 99.1%–99.6% (p < 0.0001) of changes of indicators explained by pH. In manure treatments, the indicators correlated with DO and pH (r = 0.92 to 0.998) (p < 0.0001), with 98.1%–99.7% (p < 0.0001) of changes explained by DO and pH. NPK and layer manure have deleterious effect on C. gariepinus early stages. The toxicity and explanatory physico‐chemical parameters should be considered when the fertilizers target aquatic productivity.  相似文献   
7.
The effect of dietary inclusion of fermented pigeon pea meal (FPPM) on growth response, apparent nutrient digestibility, haematological indices and serum biochemistry of cockerel chicks was studied using 240-day-old cockerel chicks allotted to four dietary treatments consisting of 60 birds each. Four experimental diets were formulated to include FPPM at 0, 50, 100 and 150?g/kg inclusion levels, respectively. Each of the diets was fed to 60 birds replicated six times with ten birds per replicate. The feeding trial lasted for 56?days. Results indicated that final live weight (linear (L). quadratic (Q): P??0.05) by the inclusion of FPPM. Haemoglobin and serum uric acid concentrations were also reduced (P?相似文献   
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This study provides new insights into the role of photoprotection in preformed and induced defence of two wheat genotypes with contrasting phenotypes to infection by Zymoseptoria tritici. We investigated the mechanisms of the photoprotective response during early infection, including nonphotochemical quenching (NPQ), β-carotene-derived xanthophylls, reactive oxygen species, and the phytohormones abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA). Furthermore, we quantified the effects of pathogenesis on photosynthesis, stomatal control, and expression of plant defence molecular markers. The photoprotective mechanism of successful defence involved the qI component of NPQ leading to rapid down-regulation of photosystem II quantum yield and chlorophyll a:b, increased biosynthesis of the xanthophyll neoxanthin and ABA, and the expression of chloroplast-specific enzymes to engage in scavenging of O2●−. Elevated ABA in the resistant genotype correlated with preformed leaf defence traits including low stomatal density, increased expression of wax biosynthesis, and lignification. Z. tritici exhibited reduced germination and branching on the resistant host genotype and hijacked stomatal control in both genotypes by enhancing stomatal sensitivity to light. Increased biosynthesis of JA and anthocyanins, in contrast to SA, were quantified in the incompatible interaction. Our results indicate that ABA and JA in antagonistic action to SA were associated with defence in the resistant genotype, Cougar, against Z. tritici.  相似文献   
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