This study used multivariate statistics to identify clusters of animals with similar expected progeny difference (EPD) and also identify leading traits that discriminate between bulls. Various linear selection indices based on specific selection criteria were proposed. Records were collected from 880 young Nelore bulls submitted to performance testing in central Brazil between 2001 and 2012. Pre-weaning average daily gain and weights at 210 days with direct and maternal effects were used in the analysis, in addition to post-weaning weight, scrotal circumference at 365 and 450 days, carcass finish and rib eye area. EPDs were classified into three groups, and the EPD means of two of these groups stood out and were considered important based on principal component analysis that associated higher values of direct EPD of weights, average daily weight gain and scrotal circumference. The EPDs for weight at 210, 365 and 450 days, pre- and post-weaning daily gain and scrotal circumference at 365 and 450 days were major causes of variation. Each linear selection index proposed (SI₁, SI₂, SI₃, SI₄ and SI₅) defined a specific approach meaning that a different selection index should be used depending on breeding goals and selection criteria.

The seaweed-based biostimulants available in the market are proven to achieve better results than synthetic commercial fertilizers in plant growth parameters. There are many compounds present in seaweeds that are responsible for the plant bioactivities. Seaweed polysaccharides, such as agar, alginate, and carrageenan, make up most of the seaweed biomass and are proven to achieve excellent results in agricultural crops (in poly- and oligosaccharides formula). These types of compounds are reported to improve seed germination and plant vigor, increase the uptake of soil nutrients, and protect plants against several abiotic and biotic stresses such as salinity, drought, temperature, and pathogens. When applied to the soil directly or sprayed on the foliage, seaweed poly- and oligosaccharides can protect plants against pathogens by stimulating a plant to produce secondary metabolites and manage its defense pathways. Therefore, seaweed poly- and oligosaccharides constitute an important source of potential elicitors in plants and have a particular interest for agriculture. Thus, in this review, the focus is on the potential application of these compounds in the agricultural domain: problems, obstacles, and possibilities.

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