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Fertilizer management influences the accumulation of soil organic C and N in agricultural soils. The combined use of chemical and organic fertilizers is considered a good method to enhance soil fertility, but it is still unclear about the effects of substituting manure for fertilizer on aggregation and aggregate associated organic C and N. We selected a 4-yr-old soil fertility experiment to examine the aggregation and aggregate associated organic C and N in response to substituting manure for fertilizer. In comparison to control, no fertilizer added (CK); substituting manure for fertilizer significantly increased organic C and N by 11.61 to 47.97% and 21.05 to 32.63% in 0- to 20-cm bulk soil, respectively. It promoted organic C in the silt + clay fraction, microaggregates, small macroaggregates, and large macroaggregates by 3.17 to 17.15%, 12.94 to 34.09%, 10.99 to 50.20%, and 25.32 to 52.09%, respectively. Aggregate associated N also presented significant increases under substituting manure for fertilizer compared to CK. The mass distribution of small and large macroaggregates were 8.16 to 15.54% and 8.89 to 49.51% higher in the manure-substituted plots than CK, respectively. Organic C and labile C were generally greater in macro-than microaggregates in the manure-substituted plots; redundancy analysis confirmed that macroaggregates had positive effects on organic C and N sequestration in bulk soil and aggregates. Based on these results we suggested that substituting manure increases macroaggregate associated organic C and N, and the formation of small and large macroaggregates is accelerated by organic amendment in the test soil compared to CK. [ABSTRACT FROM AUTHOR]

The article presents a study that used canine adenovirus type 2 (CAV-2) to express GP5 and M proteins to create a vaccine candidate against the porcine reproductive and respiratory syndrome virus (PRRSV). Researchers evaluated the immunogenicity of the recombinant virus by innoculating mice with the canine adenovirus type 2 (CAV-2) recombinant (rCAV2-GP5/M) they developed. They found that lymphocyte proliferation responded to PRRSV antigens two weeks after immunization (w.p.i.), and that the neutralizing antibody titers were relatively high and induced early.