Prevalence and risk factors associated with bovine brucellosis in herds under extensive production system in southwestern Nigeria

Using a cross-sectional survey, we determined the prevalence and risk factors associated with bovine brucellosis in herds under extensive production system in southwestern Nigeria. Antibodies to Brucella species in serum samples were tested using the Rose Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA); for milk, the milk ring test (MRT) and indirect-ELISA (i-ELISA) were used. Questionnaire was administered to cattle herdsmen to determine factors predisposing the animals to bovine brucellosis. Data were analyzed using STATA 12. From 513 serum and 635 milk samples tested among 120 herds, overall animal-level prevalence of 10.1% (95% CI 7.5–12.7%) and 20.2% (95% CI 17.1–23.3%) were recorded by RBT and MRT, respectively; while 9.4% (95% CI 6.9–11.9%) and 17.8% (95% CI 14.8–20.8%) were obtained using cELISA and i-ELISA, respectively. In all, from the 120 herds tested, 29.2% and 43.3% were positive by RBT and MRT, respectively. Multivariable logistic regression revealed that herd location (OR?=?8.12, 95% CI 1.68–38.90) and improper disposal of placenta/fetus (OR?=?17.33, 95% CI 4.81–62.33) were predictors for a seropositive herd using RBT; while herd location (OR?=?5.13, 95% CI 1.27–20.28), large herd size (OR?=?2.62, 95% CI 1.15–5.85), and occurrence of abortion for a year or more (OR?=?4.62, 95% CI 1.53–13.71) were predictors of seropositivity to antibodies to Brucella spp. using MRT. We found high prevalence of brucellosis in cattle herds under extensive management system in southwestern Nigeria. Urgent and coordinated control strategies are required to mitigate this problem.

     

Effects of Sodium and Potassium Application on Water Content and Yield of Tomato in Southwestern Nigeria

The effects of sodium (Na) and potassium (K) application on tomato (Lycopersicon esculentum (L.) Mill) were studied in soil culture. The study was a 4 × 4 factorial, arranged into a randomized complete block design (RCBD) and replicated four times. Sodium was applied at 0, 5, 10, and 20 mg Na/kg soil as NaCl and K as KCl at 0, 20, 40, and 80 mg K/kg soil. Records of dry matter yields, water content, mineral nutrient, and number of fruits were taken. The application of 10 to 20 mg Na/kg soil and 80 mg K/kg soil depressed the water contents and the fruit yield. The application of 5 mg Na/kg soil and 40 mg K/kg soil produced the highest number of fruits, indicating a Na and K ratio of 1:8. A Na: K ratio of 0.45 up to 0.60 and 1.44 up to 1.80 for shoot and root, respectively, maintained good shoot water balance, resulted in lower floral abortion, and markedly enhanced the fruit yield. A complimentary relationship between Na and K was observed at Na: K ratios between 1:4 and 1:8.     

Factors influencing the biochemical markers for predicting Mammalian oocyte quality

The need for accurate selection of the best oocytes for in vitro fertilization protocols and thus, production of embryos has driven the search for oocyte quality markers from morphological criteria to biochemical parameters. Current studies are focused on the biochemical constituents of the follicular fluid and gene expression profiling of the cumulus cells. These parameters are, however, affected by factors that must be considered before making a judgment of the oocyte's quality. These includes factors such as the type of hormonal stimulation protocol, age of oocyte donor and heat stress on the donor, all of which have been reported to influence the concentrations of many hormones, apolipoproteins, metabolites, fatty acids and growth factors in the follicular fluid and the expression of several genes in the cumulus cells. Another important point to note is species variation in the response to these extraneous influences, which thus calls for species targeted investigations. As reports are still scanty and investigations assumed to be very keen, we employed this review paper to bring attention of researchers and clinicians to those factors that may come to bear on the outcome of their investigations on oocyte and embryo quality.     

Physicochemical characteristics of flours of faba bean as influenced by processing methods

Wet- and dry-processing with and without heating treatments were used to dehull faba beans for preparation of flours from the cotyledons. Flour qualities were assessed by levels of tannin and trypsin inhibitor and other measures of proximate composition. High roasting temperature and shorter process time that improved the recovered cotyledon yields were verified significant by path analysis methodologies. In turn, the higher cotyledon recoveries correlated with higher protein levels and inversely with the measured tannin levels. Ash reductions were correlated to the wet processing options in hull removal while reductions in the insoluble dietary fiber were notably influenced by level of heating temperatures applied. Trypsin inhibitor levels ranged from 42 to 56% of the original with reductions tied to applications of wet and/or heat processing in each case improved by increased durations and temperatures of treatments.     

Grape pomace's potential on semi-arid soil health enhances performance of maize,wheat, and grape crops

Background

Grape pomace (GP) is a by-product of wineries after filtering the grape juice for wine production. GP contains seeds, pulp, skin, and stalks with acidic properties, and it is normally composted before using as a soil amendment. However, composting GP requires more time, labor, and equipment; furthermore, composting loses some of the desirable organic acids for arid soils. The acidic properties of these organic acids and the plant nutrients in GP make it a desirable amendment for arid soils in both non-composted and composted forms.

Aim

This study investigates the potential of directly applying GP as a soil amendment and its impact on arid soil health and plant performance.

Methods

To test the potential of non-composted GP as a soil amendment, greenhouse and field studies were conducted by combining GP with existing management practices (manure application for soil used in the greenhouse study and fertigation for the field study) to assess the effects of GP on soil health and crop (maize, wheat, and grape) performance.

Results

Adding 5% GP to an alkaline soil significantly increased maize and wheat growth and shoot nutrient concentrations in the greenhouse and grapes in the field (48% yield increase). The significance of GP on maize, wheat, and grapes was associated with soil nutrient enhancements (i.e., nutrients supplied, increase in organic matter and microbial biomass increase, reduction in pH, and better nutrient mobilization).

Conclusion

GP has the potential for direct use as a soil amendment for soil and crop health improvement, especially in arid soils with high pH and limited soil organic matter.     

Nutrient Mineralization from Nitrogen- and Phosphorus-Enriched Poultry Manure Compost in an Ultisol

The combination of inorganic fertilizers and compost is a technique aimed at improving crop growth and maintaining soil health. Understanding the rate of nutrient release from enriched compost is important for effective nutrient management. A laboratory incubation study was conducted for 112 days to study the nutrient mineralization pattern of poultry manure compost enriched with inorganic nitrogen (N) and phosphorus (P) fertilizer nutrients in an Ultisol. Compost applied at the rate of either 5 or 10 g kg^?1 was blended with N (50 kg N ha^?1) and P (30 kg P ha^?1). Carbon dioxide evolution and N and P mineralization were measured fortnightly. The bacterial and fungal populations were determined at the mid and end of the experiment. The combination of compost and inorganic N and P increased carbon (C) and P mineralization by 4?8% and 56?289%, respectively, over the application of either compost or inorganic N and P. However, P addition influenced the amount of C mineralized. Inorganic N and P, on the other hand, were better at increasing N mineralization than compost blended with inorganic N and P over a short time. The addition of compost stimulated bacterial and actinomycete populations, while fungal populations were unaffected. Actinomycetes and bacteria had similar and higher relationship trend with C (R² = 0.24) and P (R² = 0.47) mineralization and were key determinants in nutrient mineralization from compost in this Ultisol. Integrating compost with inorganic fertilizers improves nutrient availability through the growth and activities of beneficial microorganisms.     

Current status,opportunities, and challenges of cover cropping for sustainable dryland farming in the Southern Great Plains

Cropping systems that integrate cover crops into crop rotations, reduce tillage intensity and frequency, and maintain residue cover have the potential to improve agricultural sustainability in drylands. However, there is much yet to learn about the benefits of cover crops in sustainable dryland farming in the southern Great Plains (SGP). We reviewed the literature on the effects of cover crops on soil organic carbon (SOC), nitrogen, soil water conservation, and crop yields in dryland cropping systems of the US Great Plains (GP), and analyzed the opportunities and challenges for integrating cover crops into dryland crop-fallow systems of the SGP. Majority of the studies in the central Great Plains (CGP) and the northern Great Plains (NGP) of the United States suggest that cover cropping improves sustainability of cropping systems through their positive effects on SOC accumulation, nutrient cycling, soil erosion control, weed suppression, and soil health improvement. However, integrating cover crops into dryland cropping systems of the SGP faces challenges because of low quantity of soil-water availability. More research on the tradeoff between water use and other agroecosystem benefits of cover cropping is required to successfully integrate cover crops into dryland cropping systems in the SGP.